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Sample records for mercury inhalation toxicity

  1. Inhalational mercury toxicity from artisanal gold extraction reported to the Oregon poison center, 2002-2015.

    Science.gov (United States)

    Noble, Matthew J; Decker, Stewart L; Horowitz, B Z

    2016-11-01

    Mercury exposure has been described among small-scale gold mining communities in developing countries, but reports of inhalational mercury toxicity among home gold extractors in the US remain uncommon. We sought to identify inhalational mercury exposures and toxicity among artisanal gold extractors. This is an observational case series of a single Poison Center database from 2002-2015. We review all cases of "mercury" or "mercury inhalation" exposures, with detailed description of a recent representative case. Nine cases were reported, with patients' ages ranging 32-81 years. Eight (89%) patients were male. Seven of eight (88%) patients with acute exposures reported pulmonary symptoms consistent with mercury vapor inhalation such as dyspnea and cough; two (29%) patients had severe toxicity requiring intubation. Four of six (67%) patients had markedly elevated whole blood mercury concentrations up to 346 mcg/L; each received a different chelation regimen. Four (44%) patients used methamphetamines at the time of their exposure. The case report describes a patient with elevated mercury concentrations who required intubation for hypoxic respiratory failure. He received chelation therapy based on chelator availability, with decreasing 24-hour urine mercury concentrations. The house where he was exposed remains uninhabitable from elevated ambient mercury vapor concentrations. Artisanal gold extraction may be associated with inhalational mercury toxicity, including elevated blood mercury concentrations and acute hypoxic lung injury requiring intubation.

  2. Pneumonitis after Inhalation of Mercury Vapours

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    JD Glezos

    2006-01-01

    Full Text Available A 43-year-old man presented to hospital with pneumonia but only after discharge from hospital did he admit to deliberate prior inhalation of mercury. His pulmonary involvement appeared to resolve almost completely with antibiotics and supportive care. Nevertheless, persisting elevated urinary excretion of mercury required two courses of chelation therapy. No serious systemic sequelae were observed.

  3. Mercury vapor inhalation and poisoning of a family.

    Science.gov (United States)

    Oz, Serife Gul; Tozlu, Mukaddes; Yalcin, Songul Siddika; Sozen, Tumay; Guven, Gulay Sain

    2012-08-01

    Acute mercury vapor poisoning is a rare but fatal toxicological emergency. People are exposed to mercury in daily life by the way of foods, vaccines, antiseptics, ointments, amalgam or occupation. We present here, the clinical picture and management of four members of the same family who were exposed to elemental mercury. Three of the family members were seen in another hospital with malaise, fever, eritematous rash and pulmonary problems. Their questioning revealed the mercury exposure. Having a suspicion of heavy metal intoxication, blood and urine mercury levels were measured and mercury intoxication was diagnosed. On admission to our hospital, two patients already had chelation therapy. In three of them we found three distinct abnormalities: encephalopathy, nephrotic syndrome and polyneuropathy. The fourth family member had minor symptoms. This family is an example for the inhalation exposure resulting from inappropriate handling of liquid mercury. During the first days, flu like illness ensues. Then, severe pulmonary, neurological, renal, hepatic, hematological and dermatological dysfunctions develop. Blood and urine mercury levels should be tested on suspicion, but it must be kept in mind that blood level is unreliable in predicting the severity of mercury toxicity. The priority in the treatment should be removing the patient from the source of exposure. Then British anti-Lewisite, edetate calcium disodium, penicillamine, Sodium 2,3-dimercaptopropane-1-sulfhonate and 2,3-dimercaptosuccinic acid can be used for binding the mercury. We conclude that since mercury-containing devices are present in daily life, physicians must be able to recognize the clinical manifestations and treatment of mercury poisoning.

  4. Mercury toxicity and neurodegenerative effects.

    Science.gov (United States)

    Carocci, Alessia; Rovito, Nicola; Sinicropi, Maria Stefania; Genchi, Giuseppe

    2014-01-01

    Mercury is among the most toxic heavy metals and has no known physiological role in humans. Three forms of mercury exist: elemental, inorganic and organic. Mercury has been used by man since ancient times. Among the earliest were the Chinese and Romans, who employed cinnabar (mercury sulfide) as a red dye in ink (Clarkson et al. 2007). Mercury has also been used to purify gold and silver minerals by forming amalgams. This is a hazardous practice, but is still widespread in Brazil's Amazon basin, in Laos and in Venezuela, where tens of thousands of miners are engaged in local mining activities to find and purify gold or silver. Mercury compounds were long used to treat syphilis and the element is still used as an antiseptic,as a medicinal preservative and as a fungicide. Dental amalgams, which contain about 50% mercury, have been used to repair dental caries in the U.S. since 1856.Mercury still exists in many common household products around the world.Examples are: thermometers, barometers, batteries, and light bulbs (Swain et al.2007). In small amounts, some organo mercury-compounds (e.g., ethylmercury tiosalicylate(thimerosal) and phenylmercury nitrate) are used as preservatives in some medicines and vaccines (Ballet al. 2001).Each mercury form has its own toxicity profile. Exposure to Hg0 vapor and MeHg produce symptoms in CNS, whereas, the kidney is the target organ when exposures to the mono- and di-valent salts of mercury (Hg+ and Hg++, respectively)occur. Chronic exposure to inorganic mercury produces stomatitis, erethism and tremors. Chronic MeHg exposure induced symptoms similar to those observed in ALS, such as the early onset of hind limb weakness (Johnson and Atchison 2009).Among the organic mercury compounds, MeHg is the most biologically available and toxic (Scheuhammer et a!. 2007). MeHg is neurotoxic, reaching high levels of accumulation in the CNS; it can impair physiological function by disrupting endocrine glands (Tan et a!. 2009).The most

  5. Health risks associated with inhaled nasal toxicants

    NARCIS (Netherlands)

    Feron, V.J.; Arts, J.H.E.; Kuper, C.F.; Slootweg, P.J.; Woutersen, R.A.

    2001-01-01

    Health risks of inhaled nasal toxicants were reviewed with emphasis on chemically induced nasal lesions in humans, sensory irritation, olfactory and trigeminal nerve toxicity, nasal immunopathology and carcinogenesis, nasal responses to chemical mixtures, in vitro models, and nasal dosimetry- and me

  6. Mercury

    Science.gov (United States)

    ... and treatments are needed. ELEMENTAL MERCURY Inhaled elemental mercury poisoning may be difficult to treat. The person may ... metals from the body INORGANIC MERCURY For inorganic mercury poisoning, treatment often begins with supportive care. The person ...

  7. Inhalation toxicity of high flash aromatic naphtha.

    Science.gov (United States)

    Clark, D G; Butterworth, S T; Martin, J G; Roderick, H R; Bird, M G

    1989-05-01

    A petroleum distillate--a high aromatic naphtha--consisting of a 50/50 blended mixture of equivalent products. SHELLSOL A* and SOLVESSO 100**, containing C9 isomers (75 percent) particularly trimethyl benzenes, was examined for systemic toxicity in rats by inhalation exposure. A preliminary 13-week inhalation study with SHELLSOL A had resulted in liver and kidney weight increases in female rats at the high (7400 mg/m3) and medium (3700 mg/m3) exposure levels, and a low grade anaemia in females at all exposure levels (7400, 3700 and 1800 mg/m3). The follow-up 12-month inhalation study in rats described here used atmosphere generated from the SHELLSOL A/SOLVESSO 100 blend of 1800, 900 and 450 mg/m3. Initial reduction in body weight gain occurred in both male and female rats at the higher exposures. Various statistically significant haematological changes were transiently seen in males up to six months, but were not considered biologically significant. High exposure male liver and kidney weights were increased at 6 and 12 months but, in the absence of histopathological changes, were considered to be physiological adaptive responses. No treatment-related histopathological abnormalities were found. It is concluded that chronic exposure to this high aromatic naphtha is without systemic toxicity in rats under the conditions of these studies.

  8. Toxic spongiform leucoencephalopathy after inhaling heroin vapour

    Energy Technology Data Exchange (ETDEWEB)

    Weber, W.; Henkes, H.; Kuehne, D. [Klinik fuer Allgemeine Roentgendiagnostik und Neuroradiologie, Alfried-Krupp-Krankenhaus, Alfried Krupp Strasse 21, D-45117, Essen (Germany); Moeller, P.; Bade, K. [Neurologische Klinik, Knappschafts-Krankenhaus, D-45657 Recklinghausen (Germany)

    1998-06-02

    This is a report of clinical, CT and MRI findings in a patient with toxic spongiform leucoencephalopathy after heroin ingestion. The disease is observed in drug addicts who inhale pre-heated heroin. The clinical onset, which usually occurs some days or even longer after the last heroin consumption, is characterized by a cerebellar syndrome. The cerebellar hemispheres, the cerebellar and cerebral peduncles and the pyramidal tract may be affected. Spongiform demyelination is the morphological substrate of the lesions, which are not contrast enhancing, hypodense on CT and hyperintense on T2-weighted MRI. The frequently perfect symmetry of the affection of functional systems points to a toxic and/or metabolic pathophysiological mechanism. (orig.) With 2 figs., 2 tabs., 26 refs.

  9. MERCURY TOXICITY AND ITS MANAGEMENT

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    Jain Rimjhim

    2013-08-01

    Full Text Available Mercury is an element that has been known for at least 4000 years (Chang 1985. It is a metal that is liquid at room temperatures and is widely used in our modern society. Today, the unique chemical and physical properties of mercury are widely used in industry, agriculture, medicine, mining, dentistry and other areas of everyday life. Some of these are used in the manufacture or processing of felt, fireworks, batteries, blackening brass, photography pigments for rubber and plastics, wine colouring and medicine. Medical compounds comprised of 75 % of the list and included antibacterial, antiseptic, topical anaesthetic, immunosuppressant, anti-infective and fungicide, diuretic, cathartic and preservative agents. There are two goals to treatment. First, get rid of the mercury, second, control symptoms so you can be comfortable and productive during the prolonged period when mercury is removed and healing takes place. In order to control the symptoms it is necessary to identify the metabolic defects mercury is causing for you.

  10. Mercury Toxicity and Treatment: A Review of the Literature

    Science.gov (United States)

    Bernhoft, Robin A.

    2012-01-01

    Mercury is a toxic heavy metal which is widely dispersed in nature. Most human exposure results from fish consumption or dental amalgam. Mercury occurs in several chemical forms, with complex pharmacokinetics. Mercury is capable of inducing a wide range of clinical presentations. Diagnosis of mercury toxicity can be challenging but can be obtained with reasonable reliability. Effective therapies for clinical toxicity have been described. PMID:22235210

  11. Mercury Toxicity and Treatment: A Review of the Literature

    Directory of Open Access Journals (Sweden)

    Robin A. Bernhoft

    2012-01-01

    Full Text Available Mercury is a toxic heavy metal which is widely dispersed in nature. Most human exposure results from fish consumption or dental amalgam. Mercury occurs in several chemical forms, with complex pharmacokinetics. Mercury is capable of inducing a wide range of clinical presentations. Diagnosis of mercury toxicity can be challenging but can be obtained with reasonable reliability. Effective therapies for clinical toxicity have been described.

  12. Subchronic inhalation toxicity of gold nanoparticles

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    Chung Yong

    2011-05-01

    Full Text Available Abstract Background Gold nanoparticles are widely used in consumer products, including cosmetics, food packaging, beverages, toothpaste, automobiles, and lubricants. With this increase in consumer products containing gold nanoparticles, the potential for worker exposure to gold nanoparticles will also increase. Only a few studies have produced data on the in vivo toxicology of gold nanoparticles, meaning that the absorption, distribution, metabolism, and excretion (ADME of gold nanoparticles remain unclear. Results The toxicity of gold nanoparticles was studied in Sprague Dawley rats by inhalation. Seven-week-old rats, weighing approximately 200 g (males and 145 g (females, were divided into 4 groups (10 rats in each group: fresh-air control, low-dose (2.36 × 104 particle/cm3, 0.04 μg/m3, middle-dose (2.36 × 105 particle/cm3, 0.38 μg/m3, and high-dose (1.85 × 106 particle/cm3, 20.02 μg/m3. The animals were exposed to gold nanoparticles (average diameter 4-5 nm for 6 hours/day, 5 days/week, for 90-days in a whole-body inhalation chamber. In addition to mortality and clinical observations, body weight, food consumption, and lung function were recorded weekly. At the end of the study, the rats were subjected to a full necropsy, blood samples were collected for hematology and clinical chemistry tests, and organ weights were measured. Cellular differential counts and cytotoxicity measurements, such as albumin, lactate dehydrogenase (LDH, and total protein were also monitored in a cellular bronchoalveolar lavage (BAL fluid. Among lung function test measurements, tidal volume and minute volume showed a tendency to decrease comparing control and dose groups during the 90-days of exposure. Although no statistically significant differences were found in cellular differential counts, histopathologic examination showed minimal alveoli, an inflammatory infiltrate with a mixed cell type, and increased macrophages in the high-dose rats. Tissue

  13. Subchronic inhalation toxicity of gold nanoparticles.

    Science.gov (United States)

    Sung, Jae Hyuck; Ji, Jun Ho; Park, Jung Duck; Song, Moon Yong; Song, Kyung Seuk; Ryu, Hyeon Ryol; Yoon, Jin Uk; Jeon, Ki Soo; Jeong, Jayoung; Han, Beom Seok; Chung, Yong Hyun; Chang, Hee Kyung; Lee, Ji Hyun; Kim, Dong Won; Kelman, Bruce J; Yu, Il Je

    2011-05-14

    Gold nanoparticles are widely used in consumer products, including cosmetics, food packaging, beverages, toothpaste, automobiles, and lubricants. With this increase in consumer products containing gold nanoparticles, the potential for worker exposure to gold nanoparticles will also increase. Only a few studies have produced data on the in vivo toxicology of gold nanoparticles, meaning that the absorption, distribution, metabolism, and excretion (ADME) of gold nanoparticles remain unclear. The toxicity of gold nanoparticles was studied in Sprague Dawley rats by inhalation. Seven-week-old rats, weighing approximately 200 g (males) and 145 g (females), were divided into 4 groups (10 rats in each group): fresh-air control, low-dose (2.36 × 104 particle/cm3, 0.04 μg/m3), middle-dose (2.36 × 105 particle/cm3, 0.38 μg/m3), and high-dose (1.85 × 106 particle/cm3, 20.02 μg/m3). The animals were exposed to gold nanoparticles (average diameter 4-5 nm) for 6 hours/day, 5 days/week, for 90-days in a whole-body inhalation chamber. In addition to mortality and clinical observations, body weight, food consumption, and lung function were recorded weekly. At the end of the study, the rats were subjected to a full necropsy, blood samples were collected for hematology and clinical chemistry tests, and organ weights were measured. Cellular differential counts and cytotoxicity measurements, such as albumin, lactate dehydrogenase (LDH), and total protein were also monitored in a cellular bronchoalveolar lavage (BAL) fluid. Among lung function test measurements, tidal volume and minute volume showed a tendency to decrease comparing control and dose groups during the 90-days of exposure. Although no statistically significant differences were found in cellular differential counts, histopathologic examination showed minimal alveoli, an inflammatory infiltrate with a mixed cell type, and increased macrophages in the high-dose rats. Tissue distribution of gold nanoparticles showed a dose

  14. Detoxification Mechanisms of Mercury Toxicity in Plants: A Review

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    Shilpa Shrivastava

    2015-12-01

    Full Text Available Mercury is one of the most toxic heavy metals present in the earth’s crust. It has been considered as environmental pollutant because of its potent toxicity to plants and humans. In this review, we discuss mercury toxicity responses on plant metabolism and its detoxification mechanism by phytochelatins and antioxidant enzymes. Some light is also shed on selenium antagonistic study with mercury. Due to its potential toxicity, it has attracted attention in fields of soil science and plant nutrition. Mercury has harmful toxic effects on the molecular and physiobiochemical behavior of plants. Mostly research work has been done on seed germination, and shoot, root, and leaf morphology. Enzyme responses with respect to mercury as a result Hg accumulated in food chain is also reviewed here. Hence, this review may provide a compiled data for other researches in this direction, to provide a better mechanism or details about mercury’s noxious effect in the ecosystem.

  15. Toxic alveolitis after inhalation of a water repellent.

    Science.gov (United States)

    Epping, Guido; Van Baarlen, Joop; Van Der Valk, Paul D L P M

    2011-12-01

    Inhalation of fluorocarbon polymers can cause pulmonary toxicity. Although multiple cases of lung injury have been reported, cellular characterization of the associated alveolitis occurring acutely after inhalation is limited. We report the case of a previously healthy woman who presented at our Emergency Department with an acute pneumonitis following inhalation of a fluorocarbon polymer-based rain-proofing spray. Bronchoalveolar lavage (BAL) performed shortly after the presentation showed an elevated total cell count, with a high proportion of neutrophils (58%) and eosinophils (9%). In addition, a lipid stain (Oil-Red-O-stain) showed a high level of lipid laden macrophages, a marker that could reflect a direct toxic effect of the spray on alveolar cells. The patient made a full recovery after four days of in-hospital observation with supportive care.

  16. 90-Day Inhalation Toxicity Study of FT Fuel

    Science.gov (United States)

    2011-08-01

    vapors of a distillate of light catalytic cracked naphtha (LCCN-D, CAS no. 64741-55-5) in Sprague-Dawley rats. Target exposure concentrations were 0...cracked naphtha distillate in rats. Int J Toxicol. (2001) 20:307-319. McDougal JN, Rogers JV. Local and systemic toxicity of JP-8 from cutaneous exposures...petroleum blending streams: inhalation subchronic toxicity/neurotoxicity study of a light catalytic reformed naphtha distillate in rats. J Toxicol

  17. The toxicity of inhaled methanol vapors

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    Kavet, R.; Nauss, K.M. (Environmental Research Information, Inc., Palo Alto, CA (USA))

    1990-01-01

    Methanol could become a major automotive fuel in the U.S., and its use may result in increased exposure of the public to methanol vapor. Nearly all of the available information on methanol toxicity in humans relates to the consequences of acute, rather than chronic, exposures. Acute methanol toxicity evolves in a well-understood pattern and consists of an uncompensated metabolic acidosis with superimposed toxicity to the visual system. The toxic properties of methanol are rooted in the factors that govern both the conversion of methanol to formic acid and the subsequent metabolism of formate to carbon dioxide in the folate pathway. In short, the toxic syndrome sets in if formate generation continues at a rate that exceeds its rate of metabolism. Current evidence indicates that formate accumulation will not challenge the metabolic capacity of the folate pathway at the anticipated levels of exposure to automotive methanol vapor.117 references.

  18. 40 CFR 798.2450 - Inhalation toxicity.

    Science.gov (United States)

    2010-07-01

    ... toxicological evaluation include: Analyses of lipids, hormones, acid/base balance, methemoglobin, and... 798.2450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES...: Electrolyte balance, carbohydrate metabolism, and liver and kidney function. The selection of specific tests...

  19. Acute inhalation toxicity of carbonyl sulfide

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    Benson, J.M.; Hahn, F.F.; Barr, E.B. [and others

    1995-12-01

    Carbonyl sulfide (COS), a colorless gas, is a side product of industrial procedures sure as coal hydrogenation and gasification. It is structurally related to and is a metabolite of carbon disulfide. COS is metabolized in the body by carbonic anhydrase to hydrogen sulfide (H{sub 2}S), which is thought to be responsible for COS toxicity. No threshold limit value for COS has been established. Results of these studies indicate COS (with an LC{sub 50} of 590 ppm) is slightly less acutely toxic than H{sub 2}S (LC{sub 50} of 440 ppm).

  20. [Mercury poisoning].

    Science.gov (United States)

    Bensefa-Colas, L; Andujar, P; Descatha, A

    2011-07-01

    Mercury is a widespread heavy metal with potential severe impacts on human health. Exposure conditions to mercury and profile of toxicity among humans depend on the chemical forms of the mercury: elemental or metallic mercury, inorganic or organic mercury compounds. This article aims to reviewing and synthesizing the main knowledge of the mercury toxicity and its organic compounds that clinicians should know. Acute inhalation of metallic or inorganic mercury vapours mainly induces pulmonary diseases, whereas chronic inhalation rather induces neurological or renal disorders (encephalopathy and interstitial or glomerular nephritis). Methylmercury poisonings from intoxicated food occurred among some populations resulting in neurological disorders and developmental troubles for children exposed in utero. Treatment using chelating agents is recommended in case of symptomatic acute mercury intoxication; sometimes it improves the clinical effects of chronic mercury poisoning. Although it is currently rare to encounter situations of severe intoxication, efforts remain necessary to decrease the mercury concentration in the environment and to reduce risk on human health due to low level exposure (dental amalgam, fish contamination by organic mercury compounds…). In case of occupational exposure to mercury and its compounds, some disorders could be compensated in France. Clinicians should work with toxicologists for the diagnosis and treatment of mercury intoxication.

  1. Cadmium inhalation and male reproductive toxicity

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    Ragan, H.A.; Mast, T.J. (Battelle Pacific Northwest Laboratories, Richland, WA (USA))

    1990-01-01

    Cadmium is a highly toxic element that is cumulative and has a long biological half-life in mammals. The severe toxicity of cadmium in man has been known for more than 100 years. Despite the knowledge that cadmium is toxic, only 20 human cases of poisoning via ingestion were recorded prior to 1941, whereas in the ensuing five-year period more than 680 cases of cadmium poisonings from accidental oral ingestion of this metal were documented. Some of the recorded effects of exposure to cadmium in laboratory animals include renal tubular damage, placental and testicular necrosis, structural and functional liver damage, osteomalacia, testicular tumors, teratogenic malformations, anemia, hypertension, pulmonary edema, chronic pulmonary emphysema, and induced deficiencies of iron, copper, and zinc. Some of these effects have also been observed in human after accidental exposures to cadmium oxide fumes and are characteristic of the syndrome described in Japan as Itai Itai disease in which ingestion of cadmium is the inciting chemical.134 references.

  2. Toxicity of mercury in macrophages. Structure and function of macrophages after experimental mercury exposure

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, M.M.

    1995-12-31

    Mercury is recognized as an environmental heavy metal pollutant with a toxic effect on living organisms. The toxicity of this heavy metal at cellular level is described for many types of cells. Macrophages are ubiquitous in the organism and play a central role in the non-specific defence barrier against intruding micro-organisms. As a first line of defence, macrophages are crucial for the course of generalized infection, for instance with herpes simplex virus. Functions such as phagocytosis, migration, activation during infection and cytokine production are important in this context. Mercury, detectable by auto metallography, is found in the lysosomes of macrophages and this accumulation is dependent upon dose and length of time of mercury exposure. But higher concentrations cause auto interference, which indicates that mercury accumulation is dependent on lysosome functional integrity and that mercury inhibits lysosome functions. In mice intraperitoneally exposed to mercury chloride, mercury is found localized in the lysosomes of macrophages in the spleen, thymus, lymph nodes and liver as well as in peritoneal macrophages. The effect of mercury on a virus infection was examined in studies of the course of infection in mice treated with mercury and infected with herpes simplex virus type 2 (HSV-2) under further exposure to mercury. To further elucidate aspects of interactions between heavy metals and macrophages and their eventual significance for the antiviral effect of macrophages, the effect of mercury on cell respiratory burst capacity and the influence of mercury on cell production of and reaction to cytokines was examined. This thesis shows that mercury is immunotoxic in that it affects macrophages both with regard to the viability and function of the cells. This is also valid for mercury concentrations that do not result in apparent pathological changes. (EG) 98 refs.

  3. Genetic Aspects of Susceptibility to Mercury Toxicity: An Overview.

    Science.gov (United States)

    Andreoli, Virginia; Sprovieri, Francesca

    2017-01-18

    Human exposure to mercury is still a major public health concern. In this context, children have a higher susceptibility to adverse neurological mercury effects, compared to adults with similar exposures. Moreover, there exists a marked variability of personal response to detrimental mercury action, in particular among population groups with significant mercury exposure. New scientific evidence on genetic backgrounds has raised the issue of whether candidate susceptibility genes can make certain individuals more or less vulnerable to mercury toxicity. In this review, the aim is to evaluate a new genetic dimension and its involvement in mercury risk assessment, focusing on the important role played by relevant polymorphisms, located in attractive gene targets for mercury toxicity. Existing original articles on epidemiologic research which report a direct link between the genetic basis of personal vulnerability and different mercury repercussions on human health will be reviewed. Based on this evidence, a careful evaluation of the significant markers of susceptibility will be suggested, in order to obtain a powerful positive "feedback" to improve the quality of life. Large consortia of studies with clear phenotypic assessments will help clarify the "window of susceptibility" in the human health risks due to mercury exposure.

  4. White phosphorus burns and arsenic inhalation: a toxic combination.

    Science.gov (United States)

    Berndtson, Allison E; Fagin, Alice; Sen, Soman; Greenhalgh, David G; Palmieri, Tina L

    2014-01-01

    White phosphorus is a common industrial and military compound, which can cause severe thermal and chemical burns beyond what would be predicted from body surface area alone. The authors present a rare case of a 45-year-old male patient who suffered white phosphorus burns combined with arsenic inhalation because of an industrial accident. The presented case is used to review the history and the toxicities of these chemicals as well as current methods of treatment. A literature review was performed to summarize the current knowledge of white phosphorus burns, as well as arsenic poisoning, and no similar case reports of the two combined were found. The patient ultimately recovered and was discharged, though with significant chronic complications. This case highlights the risk of burns and inhalation injury present in industrial manufacturing jobs, as well as the potential severity of these conditions. The systemic effects of chemicals absorbed across burned skin and via inhalation were the main contributors to our patient's severe illness, and required more intensive treatment than the burns themselves. Arsenic toxicity is rare and could easily have been missed without the appropriate patient history.

  5. Subchronic Inhalation Toxicity Study of n-pentane in Rats.

    Science.gov (United States)

    Kim, Jong-Kyu; Cho, Hae-Won; Han, Jeong-Hee; Lee, Sung-Bae; Chung, Yong-Hyun; Rim, Kyung-Taek; Yang, Jeong-Sun

    2012-09-01

    This study was conducted in order to obtain information concerning the health hazards that may result from a 13 week inhalation exposure of n-pentane in Sprague-Dawley rats. This study was conducted in accordance with the Organization for Economic Co-operation and Development (OECD) guidelines for the testing of chemicals No. 413 'Subchronic inhalation toxicity: 90-day study (as revised in 2009)'. The rats were divided into 4 groups (10 male and 10 female rats in each group), and were exposed to 0, 340, 1,530, and 6,885 ppm n-pentane in each exposure chamber for 6 hour/day, 5 days/week, for 13 weeks. All of the rats were sacrificed at the end of the treatment period. During the test period, clinical signs, mortality, body weights, food consumption, ophthalmoscopy, locomotion activity, urinalysis, hematology, serum biochemistry, gross findings, organ weights, and histopathology were assessed. During the period of testing, there were no treatment related effects on the clinical findings, body weight, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, relative organ weight, and histopathological findings. The no-observable-adverse-effect level (NOAEL) of n-pentane is evaluated as being more than 6,885 ppm (20.3 mg/L) in both male and female rats. n-pentane was not a classified specific target organ toxicity in the globally harmonized classification system (GHS).

  6. Regulatory Actions - Final Mercury and Air Toxics Standards (MATS) for Power Plants

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. This page describes Federal regulatory actions.

  7. Regulatory Actions - Proposed Mercury and Air Toxics Standards (MATS) for Power Plants

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) has proposed Mercury and Air Toxics Standards (MATS) for power plants to limit mercury, acid gases and other toxic pollution from power plants. This page includes supporting documentation and

  8. Case series of mercury toxicity among children in a hot, closed environment.

    Science.gov (United States)

    Akyildiz, Basak Nur; Kondolot, Meda; Kurtoğlu, Selim; Konuşkan, Bahadir

    2012-03-01

    Mercury poisoning is much more prevalent in the general population than possibly many physicians realize. We present data on 26 pediatric cases with mercury intoxication from exposure to mercury by inhalation or skin contact as a result of a broken thermometer in a school laboratory. This is the largest pediatric series in Turkey. During a 3-month period, the study team observed the children for clinical symptoms, physical findings, and blood and mercury levels. Of all patients, 21 inhaled, 3 inhaled and touched the element, and 2 took the mercury home. Sixteen children were symptomatic at admission, although blood mercury levels in the symptomatic children were higher than those in asymptomatic children (P = 0.003). The urine mercury levels were not statistically different between the groups at the admission (P > 0.05). The exposure times were 3.5 and 2 hours for symptomatic and asymptomatic children, respectively (P = 0.003). The 2 children who took the mercury home had the highest blood mercury levels and the most prolonged exposure time. N-acetylcysteine and chelation treatments were started in 21 children who had symptoms of mercury intoxication and high mercury levels in their blood or urine. No adverse effects were observed during chelation therapy. Prompt removal of children from contaminated environments and proper decontamination or elimination of devices containing large amounts of mercury from schools are necessary to prevent serious complications caused by exposure to mercury.

  9. Inhalation toxicity of lithium combustion aerosols in rats

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    Greenspan, B.J.; Allen, M.D.; Rebar, A.H.

    1986-01-01

    Studies of the acute inhalation toxicity of lithium combustion aerosols were undertaken to aid in evaluating the health hazards associated with the proposed use of lithium metal in fusion reactors. Male and female F344/Lov rats, 9-12 wk of age, were exposed once for 4 h to concentrations of 2600, 2300, 1400, or 620 mg/m/sup 3/ of aerosol (MMAD = 0.69 ..mu..m, sigma/sub g/ = 1.45) that was approximately 80% lithium carbonate and 20% lithium hydroxide to determine the acute toxic effects. Fourteen-day LC50 values (with 95% confidence limits) of 1700 (1300-2000) mg/m/sup 3/ for the male rats and 2000 (1700-2400) mg/m/sup 3/ for the female rate were calculated. Clinical signs of anorexia, dehydration, respiratory difficulty, and perioral and perinasal encrustation were observed. Body weights were decreased the first day after exposure in relation to the exposure concentration. In animals observed for an additional 2 wk, body weights, organ weights, and clinical signs began to return to pre-exposure values. Histopathologic examination of the respiratory tracts from the animals revealed ulcerative or necrotic laryngitis, focal to segmental ulcerative rhinitis often accompanied by areas of squamous metaplasia, and, in some cases, a suppurative bronchopneumonia or aspiration pneumonia, probably secondary to the laryngeal lesions. The results of these studies indicate the moderate acute toxicity of lithium carbonate aerosols and will aid in the risk analysis of accidental releases of lithium combustion aerosols.

  10. Mercury and its toxic effects on fish

    Directory of Open Access Journals (Sweden)

    Patricia Morcillo

    2017-04-01

    Full Text Available Mercury (Hg and its derivative compounds have been parts of widespread pollutants of the aquatic environment. Since Hg is absorbed by fish and passed up the food chain to other fish-eating species, it does not only affect aquatic ecosystems but also humans through bioaccumulation. Thus, the knowledge of toxicological effects of Hg on fish has become one of the aims in research applied to fish aquaculture. Moreover, the use of alternative methods to animal testing has gained great interest in the field of Toxicology. This review addresses the systemic pathophysiology of individual organ systems associated with Hg poisoning on fish. Such data are extremely useful to the scientific community and public officials involved in health risk assessment and management of environmental contaminants as a guide to the best course of action to restore ecosystems and, in turn, to preserve human health.

  11. The mechanism of methyl mercury toxicity in isolated rat hepatocytes.

    Science.gov (United States)

    Ashour, H; Abdel-Rahman, M; Khodair, A

    1993-07-01

    Mercury is the major component of dental amalgam restorative material, which typically has 50% pure elemental mercury. It is also used in some skin creams, and in the manufacturing of plastic, drugs and fungicides. The present study was designed to investigate the toxicity of methyl mercury (MeHg+) on isolated rat hepatocytes using several toxicity parameters. The hepatocytes were isolated by a collagenase perfusion technique and were incubated with different concentrations of MeHg+ (0.1-100 ppm) for 2 h. Through the incubation period the viability was determined by Trypan blue exclusion. Reduced glutathione (GSH) content and its enzymes, glutathione peroxidase (GSH-PX) and glutathione reductase (GSH-RX) were measured. Leakage of enzymes such as aspartate transaminase (AST), and alanine transaminase (ALT) were determined. The cell viability was reduced significantly after 1 h incubation when 0.1 and 1 ppm MeHg+ were applied. The decrease in the cell viability was dose- and time-dependent. A depletion of GSH content was observed with 100 ppm MeHg+ after 30 min of incubation. A significant decrease in GSH-RX was observed with 100 ppm during 15 and 30 min of incubation, while 10 ppm of MeHg+ significantly increased ALT leakage after 60 min. However, there was a significant increase in AST leakage with 100 ppm only. The present investigation indicates that the toxic effect of MeHg+ is most likely cytosolic enzyme related.

  12. Inhalants

    Science.gov (United States)

    ... which open the breathing passages. Inhalers are very safe when used as prescribed by doctors. Inhalants, on the other hand, are common household chemicals that contain a volatile component which can be ...

  13. Toxic effects of mercury, lead and gadolinium on vascular reactivity

    Directory of Open Access Journals (Sweden)

    D.V. Vassallo

    2011-09-01

    Full Text Available Heavy metals have been used in a wide variety of human activities that have significantly increased both professional and environmental exposure. Unfortunately, disasters have highlighted the toxic effects of metals on different organs and systems. Over the last 50 years, the adverse effects of chronic lead, mercury and gadolinium exposure have been underscored. Mercury and lead induce hypertension in humans and animals, affecting endothelial function in addition to their other effects. Increased cardiovascular risk after exposure to metals has been reported, but the underlying mechanisms, mainly for short periods of time and at low concentrations, have not been well explored. The presence of other metals such as gadolinium has raised concerns about contrast-induced nephropathy and, interestingly, despite this negative action, gadolinium has not been defined as a toxic agent. The main actions of these metals, demonstrated in animal and human studies, are an increase of free radical production and oxidative stress and stimulation of angiotensin I-converting enzyme activity, among others. Increased vascular reactivity, highlighted in the present review, resulting from these actions might be an important mechanism underlying increased cardiovascular risk. Finally, the results described in this review suggest that mercury, lead and gadolinium, even at low doses or concentrations, affect vascular reactivity. Acting via the endothelium, by continuous exposure followed by their absorption, they can increase the production of free radicals and of angiotensin II, representing a hazard for cardiovascular function. In addition, the actual reference values, considered to pose no risk, need to be reduced.

  14. Toxic effects of mercury, lead and gadolinium on vascular reactivity

    Directory of Open Access Journals (Sweden)

    D.V. Vassallo

    2011-09-01

    Full Text Available Heavy metals have been used in a wide variety of human activities that have significantly increased both professional and environmental exposure. Unfortunately, disasters have highlighted the toxic effects of metals on different organs and systems. Over the last 50 years, the adverse effects of chronic lead, mercury and gadolinium exposure have been underscored. Mercury and lead induce hypertension in humans and animals, affecting endothelial function in addition to their other effects. Increased cardiovascular risk after exposure to metals has been reported, but the underlying mechanisms, mainly for short periods of time and at low concentrations, have not been well explored. The presence of other metals such as gadolinium has raised concerns about contrast-induced nephropathy and, interestingly, despite this negative action, gadolinium has not been defined as a toxic agent. The main actions of these metals, demonstrated in animal and human studies, are an increase of free radical production and oxidative stress and stimulation of angiotensin I-converting enzyme activity, among others. Increased vascular reactivity, highlighted in the present review, resulting from these actions might be an important mechanism underlying increased cardiovascular risk. Finally, the results described in this review suggest that mercury, lead and gadolinium, even at low doses or concentrations, affect vascular reactivity. Acting via the endothelium, by continuous exposure followed by their absorption, they can increase the production of free radicals and of angiotensin II, representing a hazard for cardiovascular function. In addition, the actual reference values, considered to pose no risk, need to be reduced.

  15. Toxic effects of mercury, lead and gadolinium on vascular reactivity.

    Science.gov (United States)

    Vassallo, D V; Simões, M R; Furieri, L B; Fioresi, M; Fiorim, J; Almeida, E A S; Angeli, J K; Wiggers, G A; Peçanha, F M; Salaices, M

    2011-09-01

    Heavy metals have been used in a wide variety of human activities that have significantly increased both professional and environmental exposure. Unfortunately, disasters have highlighted the toxic effects of metals on different organs and systems. Over the last 50 years, the adverse effects of chronic lead, mercury and gadolinium exposure have been underscored. Mercury and lead induce hypertension in humans and animals, affecting endothelial function in addition to their other effects. Increased cardiovascular risk after exposure to metals has been reported, but the underlying mechanisms, mainly for short periods of time and at low concentrations, have not been well explored. The presence of other metals such as gadolinium has raised concerns about contrast-induced nephropathy and, interestingly, despite this negative action, gadolinium has not been defined as a toxic agent. The main actions of these metals, demonstrated in animal and human studies, are an increase of free radical production and oxidative stress and stimulation of angiotensin I-converting enzyme activity, among others. Increased vascular reactivity, highlighted in the present review, resulting from these actions might be an important mechanism underlying increased cardiovascular risk. Finally, the results described in this review suggest that mercury, lead and gadolinium, even at low doses or concentrations, affect vascular reactivity. Acting via the endothelium, by continuous exposure followed by their absorption, they can increase the production of free radicals and of angiotensin II, representing a hazard for cardiovascular function. In addition, the actual reference values, considered to pose no risk, need to be reduced.

  16. Prediction of acute inhalation toxicity using in vitro lung surfactant inhibition

    DEFF Research Database (Denmark)

    Sørli, Jorid Birkelund; Huang, Yishi; Da Silva, Emilie

    2017-01-01

    numbers and amounts and exhibit great variety. Therefore, an alternative method to screen for acute inhalation toxicity is needed. The aim of our study was to determine if inhibition of lung surfactant by impregnation products in vitro could accurately predict toxicity in vivo in mice. We tested 21...... the chemical composition of the products and induction of toxicity. The currently accepted method for determination of acute inhalation toxicity is based on experiments on animals; it is time-consuming, expensive and causes stress for the animals. Impregnation products are present on the market in large...... impregnation products using the constant flow through set-up of the constrained drop surfactometer to determine if they inhibited LS function or not. The same products were tested in a mouse inhalation bioassay to determine their toxicity in vivo. The sensitivity was 100%, i.e. the in vitro method predicted...

  17. Mercury toxicity in the Amazon: contrast sensitivity and color discrimination of subjects exposed to mercury

    Directory of Open Access Journals (Sweden)

    A.R. Rodrigues

    2007-03-01

    Full Text Available We measured visual performance in achromatic and chromatic spatial tasks of mercury-exposed subjects and compared the results with norms obtained from healthy individuals of similar age. Data were obtained for a group of 28 mercury-exposed subjects, comprising 20 Amazonian gold miners, 2 inhabitants of Amazonian riverside communities, and 6 laboratory technicians, who asked for medical care. Statistical norms were generated by testing healthy control subjects divided into three age groups. The performance of a substantial proportion of the mercury-exposed subjects was below the norms in all of these tasks. Eleven of 20 subjects (55% performed below the norms in the achromatic contrast sensitivity task. The mercury-exposed subjects also had lower red-green contrast sensitivity deficits at all tested spatial frequencies (9/11 subjects; 81%. Three gold miners and 1 riverine (4/19 subjects, 21% performed worse than normal subjects making more mistakes in the color arrangement test. Five of 10 subjects tested (50%, comprising 2 gold miners, 2 technicians, and 1 riverine, performed worse than normal in the color discrimination test, having areas of one or more MacAdam ellipse larger than normal subjects and high color discrimination thresholds at least in one color locus. These data indicate that psychophysical assessment can be used to quantify the degree of visual impairment of mercury-exposed subjects. They also suggest that some spatial tests such as the measurement of red-green chromatic contrast are sufficiently sensitive to detect visual dysfunction caused by mercury toxicity.

  18. Subchronic inhalation toxicity of benzene in rats and mice.

    Science.gov (United States)

    Ward, C O; Kuna, R A; Snyder, N K; Alsaker, R D; Coate, W B; Craig, P H

    1985-01-01

    A subchronic inhalation toxicity study of benzene was conducted in CD-1 mice and Sprague-Dawley rats. Four groups of animals consisting of 150 mice and 50 rats/sex each were exposed to concentrations of 1, 10, 30, and 300 ppm benzene vapor, 6 hours/day, 5 days/week, for 13 weeks. Additional groups of mice and rats, of equal size, were exposed under similar conditions to filtered air and served as control groups. Thirty mice and 10 rats/sex in each group were sacrificed after 7, 14, 28, 56, and 91 days of treatment. Criteria used to evaluate exposure-related effects included behavior, body weights, organ weights, clinical pathology, gross pathology, and histopathology. Fifty animals per sex of each species were exposed concurrently for cytogenetic studies. In addition, blood serum was obtained for immunological assays. The results of these two studies will be reported separately. No consistent exposure-related trends were seen in the clinical observations and body weight data. Exposure-related clinical pathology changes were seen in the high-level (300 ppm) animals of both species. In the mice, these changes included decreases in hematocrit, total hemoglobin, erythrocyte count, leukocyte count, platelet count, myeloid/erythroid ratios, and percentage of lymphocytes. Mean cell volume, mean cell hemoglobin, glycerol lysis time, and the incidence and severity of red cell morphologic changes were increased in the mice. In the rats, decreased lymphocyte counts and a relative increase in neutrophil percentages were the only exposure-related clinical pathology alterations. Histopathologic changes were present in the thymus, bone marrow, lymph nodes, spleen, ovaries, and testes of mice exposed to 300 ppm and in most cases the incidence and severity of the lesions were greater in the males. These changes in the testes and ovaries at 300 ppm were also seen at lower concentrations, but they were of doubtful biological significance. In rats, the only exposure-related lesion

  19. A perspective on the developmental toxicity of inhaled nanoparticles

    DEFF Research Database (Denmark)

    Hougaard, Karin Sørig; Campagnolo, Luisa; Chavatte-Palmer, Pascale

    2015-01-01

    This paper aimed to clarify whether maternal inhalation of engineered nanoparticles (NP) may constitute a hazard to pregnancy and fetal development, primarily based on experimental animal studies of NP and air pollution particles. Overall, it is plausible that NP may translocate from the respirat......This paper aimed to clarify whether maternal inhalation of engineered nanoparticles (NP) may constitute a hazard to pregnancy and fetal development, primarily based on experimental animal studies of NP and air pollution particles. Overall, it is plausible that NP may translocate from...... the respiratory tract to the placenta and fetus, but also that adverse effects may occur secondarily to maternal inflammatory responses. The limited database describes several organ systems in the offspring to be potentially sensitive to maternal inhalation of particles, but large uncertainties exist about...

  20. A perspective on the developmental toxicity of inhaled nanoparticles

    NARCIS (Netherlands)

    Hougaard, Karin Sørig; Campagnolo, Luisa; Chavatte-Palmer, Pascale; Tarrade, Anne; Rousseau-Ralliard, Delphine; Valentino, Sarah; Park, Margriet V D Z; de Jong, Wim H; Wolterink, Gerrit; Piersma, Aldert H|info:eu-repo/dai/nl/071276947; Ross, Bryony L; Hutchison, Gary R; Hansen, Jitka Stilund; Vogel, Ulla; Jackson, Petra; Slama, Rémy; Pietroiusti, Antonio; Cassee, Flemming R|info:eu-repo/dai/nl/143038990

    2015-01-01

    This paper aimed to clarify whether maternal inhalation of engineered nanoparticles (NP) may constitute a hazard to pregnancy and fetal development, primarily based on experimental animal studies of NP and air pollution particles. Overall, it is plausible that NP may translocate from the respiratory

  1. Clinical expert panel on monitoring potential lung toxicity of inhaled oligonucleotides: consensus points and recommendations.

    Science.gov (United States)

    Alton, Eric W; Boushey, Homer A; Garn, Holger; Green, Francis H; Hodges, Michael; Martin, Richard J; Murdoch, Robert D; Renz, Harald; Shrewsbury, Stephen B; Seguin, Rosanne; Johnson, Graham; Parry, Joel D; Tepper, Jeff; Renzi, Paolo; Cavagnaro, Joy; Ferrari, Nicolay

    2012-08-01

    Oligonucleotides (ONs) are an emerging class of drugs being developed for the treatment of a wide variety of diseases including the treatment of respiratory diseases by the inhalation route. As a class, their toxicity on human lungs has not been fully characterized, and predictive toxicity biomarkers have not been identified. To that end, identification of sensitive methods and biomarkers that can detect toxicity in humans before any long term and/or irreversible side effects occur would be helpful. In light of the public's greater interests, the Inhalation Subcommittee of the Oligonucleotide Safety Working Group (OSWG) held expert panel discussions focusing on the potential toxicity of inhaled ONs and assessing the strengths and weaknesses of different monitoring techniques for use during the clinical evaluation of inhaled ON candidates. This white paper summarizes the key discussions and captures the panelists' perspectives and recommendations which, we propose, could be used as a framework to guide both industry and regulatory scientists in future clinical research to characterize and monitor the short and long term lung response to inhaled ONs.

  2. Long-term pulmonary and systemic toxicity following intravenous mercury injection

    Energy Technology Data Exchange (ETDEWEB)

    Dell`Omo, M.; Muzi, G.; Filiberto, S.; Abbritti, G. [Institute of Occupational Medicine, Department of Clinical Medicine, Pathology and Pharmacology, University of Perugia, Via E. dal Pozzo, 06100 Perugia (Italy); Bernard, A.; Lauwerys, R.R. [Unite de Toxicologie Industrielle et Medicine du Travail, Universite Catholique de Louvain, Clos Chapelle-aux Champs 30 - BTE 30.54, 1200 Bruxelles (Belgium)

    1997-12-01

    Long-term pulmonary and systemic toxicity following mercury intravenous injection has rarely been assessed. We present the results of a detailed investigation assessing pulmonary and systemic long-term toxic effects in a subject who had pulmonary and systemic mercury microembolism diagnosed more than 11 years previously. Radiographic examination showed the persistence of mercury microemboli in both lungs and elsewhere in the body. Lung function tests revealed a decreased diffusing capacity for carbon monoxide and Po{sub 2} probably indicative of microscopic inflammation of lung interstitium. Electroneuromyography showed signs of mild axonopathy in both legs. At semen analysis, a high proportion of motionless spermatozoa was present. Urinary excretion of mercury was high. Signs of interstitial lung impairment, peripheral axonopathy and asthenozoospermia in a subject who had mercury microembolism persisting for more than 11 years might be evidence of long-term mercury toxicity. (orig.) With 2 figs., 33 refs.

  3. Inhalation toxicity of indoor air pollutants in Drosophila melanogaster using integrated transcriptomics and computational behavior analyses

    Science.gov (United States)

    Eom, Hyun-Jeong; Liu, Yuedan; Kwak, Gyu-Suk; Heo, Muyoung; Song, Kyung Seuk; Chung, Yun Doo; Chon, Tae-Soo; Choi, Jinhee

    2017-06-01

    We conducted an inhalation toxicity test on the alternative animal model, Drosophila melanogaster, to investigate potential hazards of indoor air pollution. The inhalation toxicity of toluene and formaldehyde was investigated using comprehensive transcriptomics and computational behavior analyses. The ingenuity pathway analysis (IPA) based on microarray data suggests the involvement of pathways related to immune response, stress response, and metabolism in formaldehyde and toluene exposure based on hub molecules. We conducted a toxicity test using mutants of the representative genes in these pathways to explore the toxicological consequences of alterations of these pathways. Furthermore, extensive computational behavior analysis showed that exposure to either toluene or formaldehyde reduced most of the behavioral parameters of both wild-type and mutants. Interestingly, behavioral alteration caused by toluene or formaldehyde exposure was most severe in the p38b mutant, suggesting that the defects in the p38 pathway underlie behavioral alteration. Overall, the results indicate that exposure to toluene and formaldehyde via inhalation causes severe toxicity in Drosophila, by inducing significant alterations in gene expression and behavior, suggesting that Drosophila can be used as a potential alternative model in inhalation toxicity screening.

  4. Subacute (28-day) toxicity of furfural in Fischer 344 rats: A comparison of the oral and inhalation route

    NARCIS (Netherlands)

    Arts, J.H.E.; Muijser, H.; Appel, M.J.; Kuper, C.F.; Bessems, J.G.M.; Woutersen, R.A.

    2004-01-01

    The subacute oral and inhalation toxicity of furfural vapour was studied in Fischer 344 rats to investigate whether route-to-route extrapolation could be employed to derive the limit value for inhalation exposure from oral toxicity data. Groups of 5 rats per sex were treated by gavage daily for 28 d

  5. Mercury: Aspects of its ecology and environmental toxicity. [physiological effects of mercury compound contamination of environment

    Science.gov (United States)

    Siegel, S. M.

    1973-01-01

    A study was conducted to determine the effects of mercury pollution on the environment. The possible sources of mercury contamination in sea water are identified. The effects of mercury on food sources, as represented by swordfish, are analyzed. The physiological effects of varying concentrations of mercury are reported. Emphasis is placed on the situation existing in the Hawaiian Islands.

  6. Mercury-Resistant Marine Bacteria and their Role in Bioremediation of Certain Toxicants

    Digital Repository Service at National Institute of Oceanography (India)

    De, J.

    (LPS) layers (Langley & Beverudge, 1999). 8 The narrow mercury resistance operon (mer) comprises three major functions: transport of Hg2+ into the cell, enzymatic NADPH-dependent conversion of the ionic mercury into relatively less toxic elemental...?. Genes conferring these functions are designated as merT, merP (transport), merA (mercury reduction), mer B (cleavage of Hg from organic residue), merRandmerD (regulation). Further, more of mer genes have been identified recently; merCandmerF, both...

  7. Mercury toxicity in livers of northern pike (Esox lucius) from Isle Royale, USA.

    Science.gov (United States)

    Drevnick, Paul E; Roberts, Aaron P; Otter, Ryan R; Hammerschmidt, Chad R; Klaper, Rebecca; Oris, James T

    2008-04-01

    Many laboratory studies have documented that mercury can be toxic to fish, but it is largely unknown if mercury is toxic to fish in their natural environments. The objective of our study was to investigate the toxic effects of mercury on northern pike (Esox lucius) at Isle Royale, Michigan. In 124 northern pike from eight inland lakes, concentrations of total mercury in skin-on fillets ranged from 0.069 to 0.622 microg/g wet mass (wet wt). Concentrations of total mercury in livers increased exponentially compared with concentrations in fillets, to a maximum of 3.1 microg/g wet wt. Methylmercury constituted a majority of the mercury in livers with total mercury concentrations 0.5 microg/g wet wt. Liver color (absorbance at 400 nm) varied among northern pike and was positively related to liver total mercury concentration. The pigment causing variation in liver color was identified as lipofuscin, which results from lipid peroxidation of membranous organelles. An analysis of covariance revealed lipofuscin accumulation was primarily associated with mercury exposure, and this association obscured any normal accumulation from aging. We also documented decreased lipid reserves in livers and poor condition factors of northern pike with high liver total mercury concentrations. Our results suggest (i) northern pike at Isle Royale are experiencing toxicity at concentrations of total mercury common for northern pike and other piscivorous fish elsewhere in North America and (ii) liver color may be useful for indicating mercury exposure and effects in northern pike at Isle Royale and possibly other aquatic ecosystems and other fish species.

  8. Lung deposition analyses of inhaled toxic aerosols in conventional and less harmful cigarette smoke: a review.

    Science.gov (United States)

    Kleinstreuer, Clement; Feng, Yu

    2013-09-23

    Inhaled toxic aerosols of conventional cigarette smoke may impact not only the health of smokers, but also those exposed to second-stream smoke, especially children. Thus, less harmful cigarettes (LHCs), also called potential reduced exposure products (PREPs), or modified risk tobacco products (MRTP) have been designed by tobacco manufacturers to focus on the reduction of the concentration of carcinogenic components and toxicants in tobacco. However, some studies have pointed out that the new cigarette products may be actually more harmful than the conventional ones due to variations in puffing or post-puffing behavior, different physical and chemical characteristics of inhaled toxic aerosols, and longer exposure conditions. In order to understand the toxicological impact of tobacco smoke, it is essential for scientists, engineers and manufacturers to develop experiments, clinical investigations, and predictive numerical models for tracking the intake and deposition of toxicants of both LHCs and conventional cigarettes. Furthermore, to link inhaled toxicants to lung and other diseases, it is necessary to determine the physical mechanisms and parameters that have significant impacts on droplet/vapor transport and deposition. Complex mechanisms include droplet coagulation, hygroscopic growth, condensation and evaporation, vapor formation and changes in composition. Of interest are also different puffing behavior, smoke inlet conditions, subject geometries, and mass transfer of deposited material into systemic regions. This review article is intended to serve as an overview of contributions mainly published between 2009 and 2013, focusing on the potential health risks of toxicants in cigarette smoke, progress made in different approaches of impact analyses for inhaled toxic aerosols, as well as challenges and future directions.

  9. Examining triage patterns of inhalation injury and toxic epidermal necrolysis-Stevens Johnson syndrome.

    Science.gov (United States)

    Davis, James S; Pandya, Reeni K; Pizano, Louis R; Namias, Nicholas; Dearwater, Stephen; Schulman, Carl I

    2013-01-01

    The American Burn Association recommends that patients with toxic epidermal necrolysis-Stevens Johnson syndrome (TEN-SJS) or burn inhalation injuries would benefit from admission or transfer to a burn center (BC). This study examines to what extent those criteria are observed within a regional burn network. Hospital discharge data from 2000 to 2010 was obtained for all hospitals within the South Florida regional burn network. Patients with International Classification of Disease-9th revision discharge diagnoses for TEN-SJS or burn inhalation injury and their triage destination were compared using burn triage referral criteria to determine whether the patients were triaged differently from American Burn Association recommendations. Two hundred ninety-nine TEN-SJS and 131 inhalation injuries were admitted to all South Florida hospitals. Only 25 (8.4%) of TEN-SJS and 27 (21%) of inhalation injuries were admitted to the BC. BC patients had greater length of stay (TEN-SJS 22 vs 10 days; inhalation 13 vs 7) and were more likely to be funded by charity or be self-paid (TEN-SJS 24 vs 9.5%, P = .025; inhalation 44 vs 14%, P burn network. Unfamiliarity with triage criteria, patient insurance status, and overcoding may play a role. Further studies should fully characterize the problem and implement education or incentives to encourage more appropriate triage.

  10. Toxic effects of mercury on the cell nucleus of Dictyostelium discoideum.

    Science.gov (United States)

    Boatti, Lara; Rapallo, Fabio; Viarengo, Aldo; Marsano, Francesco

    2017-02-01

    Governmental agencies (www.epa.gov/mercury) and the scientific community have reported on the high toxicity due to mercury. Indeed, exposure to mercury can cause severe injury to the central nervous system and kidney in humans. Beyond its recognized toxicity, little is known regarding the molecular mechanisms involved in the actions of this heavy metal. Mercury has been also observed to form insoluble fibrous protein aggregates in the cell nucleus. We used D. discoideum to evaluate micronuclei formation and, since mercury is able to induce oxidative stress that could bring to protein aggregation, we assessed nuclear protein carbonylation by Western Blot. We observed a significant increase in micronuclei formation and 14 carbonylated proteins were identified. Moreover, we used isotope-coded protein label (ICPL) and mass spectrometry analysis of proteins obtained by lysis of purified nuclei, before of tryptic digestion to quantify nuclear proteins affected by mercury. In particular, we examined the effects of mercury that associate a classical genotoxic assay to proteomic effects into the nucleus. The data present direct evidences for mercury genotoxicity, nuclear protein carbonylation, quantitative change in core histones, and the involvement of pseudouridine synthase in mercury toxicity. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 417-425, 2017.

  11. Inhalants

    Science.gov (United States)

    Skip to main content En español Researchers Medical & Health Professionals Patients & Families Parents & Educators Children & Teens Search Connect with NIDA : ... get treatment for addiction to inhalants? Some people seeking treatment for ... for positive behaviors such as staying drug-free. More research is ...

  12. 40 CFR 799.9130 - TSCA acute inhalation toxicity.

    Science.gov (United States)

    2010-07-01

    ... toxicity test—(1) Principle of the test method. Several groups of experimental animals are exposed to the...) Definitions. The definitions in section 3 of TSCA and the definitions in 40 CFR Part 792—Good Laboratory Practice Standards apply to this section. The following definitions also apply to this section....

  13. 40 CFR 798.4350 - Inhalation developmental toxicity study.

    Science.gov (United States)

    2010-07-01

    ... organogenesis, to several groups of pregnant experimental animals, one exposure level being used per group...) Test procedures—(1) Animal selection—(i) Species and strain. Testing shall be performed in at least two... SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Specific Organ/Tissue Toxicity § 798...

  14. Subchronic Inhalation Toxicity Study of n-pentane in Rats

    Directory of Open Access Journals (Sweden)

    Jong-Kyu Kim

    2012-09-01

    Conclusion: The no-observable-adverse-effect level (NOAEL of n-pentane is evaluated as being more than 6,885 ppm (20.3 mg/L in both male and female rats. n-pentane was not a classified specific target organ toxicity in the globally harmonized classification system (GHS.

  15. Acute and Subchronic Toxicity of Inhaled Toluene in Male ...

    Science.gov (United States)

    The effects of exposure to volatile organic compounds (VOCs), which are of concern to the EPA, are poorly understood, in part because of insufficient characterization of how human exposure duration impacts VOC effects. Two inhalation studies with multiple endpoints, one acute and one subchronic, were conducted to seek effects of the VOC, toluene, in rats and to compare the effects between acute and subchronic exposures. Adult male Long-Evans rats were exposed to toluene vapor (n = 6 per group) at a concentration of 0 or l 019 ± 14 ppm for 6 h in the acute study and at 0 ± 0, 10 ± 1.4, 97 ± 7, or 995 ± 43 ppm for 6 h/d, 5 d/week for 13 weeksin the subchronic study. For the acute study, brains were dissected on ice within 30 min of the end of exposure, while for the subchronic study, brains were dissected 18 h after the last exposure. Frontal cortex, hippocampus, cerebellum, and striatum were assayed for a variety of oxidative stress (OS) parameters including total aconitase (TA), protein carbonyls, glutathione peroxidase (GPX), glutathione reductase (GRD), glutathione transferase (GST), y-­glutamylcysteine synthetase (GCS), superoxide dismutase (SOD), total antioxidants (TAS), NADPH quinone oxidoreductase- 1 (NQO1 ), and NADH ubiquinone reductase (UBIQ-RD) activities using commercially available kits. Following acute exposure, UBIQ-RD, GCS and GRD were increased significantly only in the cerebellum, while TAS was increased in frontal cortex. On the other

  16. Inhalation toxicity of 316L stainless steel powder in relation to bioaccessibility.

    Science.gov (United States)

    Stockmann-Juvala, H; Hedberg, Y; Dhinsa, N K; Griffiths, D R; Brooks, P N; Zitting, A; Wallinder, I Odnevall; Santonen, T

    2013-11-01

    The Globally Harmonized System for Classification and Labelling of Chemicals (GHS) considers metallic alloys, such as nickel (Ni)-containing stainless steel (SS), as mixtures of substances, without considering that alloys behave differently compared to their constituent metals. This study presents an approach using metal release, explained by surface compositional data, for the prediction of inhalation toxicity of SS AISI 316L. The release of Ni into synthetic biological fluids is >1000-fold lower from the SS powder than from Ni metal, due to the chromium(III)-rich surface oxide of SS. Thus, it was hypothesized that the inhalation toxicity of SS is significantly lower than what could be predicted based on Ni metal content. A 28-day inhalation study with rats exposed to SS 316L powder (<4 µm, mass median aerodynamic diameter 2.5-3.0 µm) at concentrations up to 1.0 mg/L showed accumulation of metal particles in the lung lobes, but no signs of inflammation, although Ni metal caused lung toxicity in a similar published study at significantly lower concentrations. It was concluded that the bioaccessible (released) fraction, rather than the elemental nominal composition, predicts the toxicity of SS powder. The study provides a basis for an approach for future validation, standardization and risk assessment of metal alloys.

  17. Lung inflammation caused by inhaled toxicants: a review

    Directory of Open Access Journals (Sweden)

    Wong J

    2016-06-01

    Full Text Available John Wong, Bruce E Magun, Lisa J Wood School of Nursing, MGH Institute of Health Professions, Boston, MA, USA Abstract: Exposure of the lungs to airborne toxicants from different sources in the environment may lead to acute and chronic pulmonary or even systemic inflammation. Cigarette smoke is the leading cause of chronic obstructive pulmonary disease, although wood smoke in urban areas of underdeveloped countries is now recognized as a leading cause of respiratory disease. Mycotoxins from fungal spores pose an occupational risk for respiratory illness and also present a health hazard to those living in damp buildings. Microscopic airborne particulates of asbestos and silica (from building materials and those of heavy metals (from paint are additional sources of indoor air pollution that contributes to respiratory illness and is known to cause respiratory illness in experimental animals. Ricin in aerosolized form is a potential bioweapon that is extremely toxic yet relatively easy to produce. Although the aforementioned agents belong to different classes of toxic chemicals, their pathogenicity is similar. They induce the recruitment and activation of macrophages, activation of mitogen-activated protein kinases, inhibition of protein synthesis, and production of interleukin-1 beta. Targeting either macrophages (using nanoparticles or the production of interleukin-1 beta (using inhibitors against protein kinases, NOD-like receptor protein-3, or P2X7 may potentially be employed to treat these types of lung inflammation without affecting the natural immune response to bacterial infections. Keywords: cigarette, mycotoxin, trichothecene, ricin, inflammasome, macrophage, inhibitors

  18. High fiber probiotic fermented mare's milk reduces the toxic effects of mercury in rats

    Directory of Open Access Journals (Sweden)

    Ahmed M. Abdel-Salam

    2010-12-01

    Full Text Available Background: Since the advent of the Industrial Revolution in the late 19th century, we have all been unfortunately exposed to an increasingly toxic and polluted world. Among the most dangerous of these pollutants is mercury, which is considered to be the most toxic non-radioactive heavy metal. Fermented foods may help cleanse the body of heavy metals. Fermentation breaks down the nutrients in foods by the action of beneficial microorganisms and creates natural chelators that are available to bind toxins and remove them from the body. Aims: The current study was designed to determine the impact of feeding a high fiber probiotic fermented mare's milk on the biological effects of mercury toxicity in rat model. Methods and Materials: The high fiber fermented mare's milk containing probiotics was prepared and its sensory properties, chemical composition, and antioxidant activity were determined. A rat model of mercury toxicity was used. The effect of feeding the high fiber probiotic fermented mare's milk to rats, along with mercury ingestion, was determined by the analysis of several biochemical markers in serum and histopathological examinations of brain and kidney. Results: The high fiber fermented mare's milk containing probiotics was found to be acceptable by all test panels and volunteers. Mercury ingestion was found to cause biochemical and histopathological alterations in rat serum and tissues. The mercury-treated rats showed a decrease in body weight and an increase in kidney weight. Sera of the mercury treated rats showed alterations in biochemical parameters, and histopathological changes in brain and kidney. However, the rats fed high fiber fermented mare`s milk along with mercury ingestion showed improved histopathology of kidney and brain, and there was restoration of the biochemical parameters in serum to almost normal values. Conclusions: Feeding high fiber fermented mare`s milk may reduce the toxic effects of mercury.

  19. Inhalation toxicity and carcinogenicity studies of cobalt sulfate.

    Science.gov (United States)

    Bucher, J R; Hailey, J R; Roycroft, J R; Haseman, J K; Sills, R C; Grumbein, S L; Mellick, P W; Chou, B J

    1999-05-01

    Cobalt sulfate is a water-soluble cobalt salt with a variety of industrial and agricultural uses. Several cobalt compounds have induced sarcomas at injection sites in animals, and reports have suggested that exposure to cobalt-containing materials may cause lung cancer in humans. The present studies were done because no adequate rodent carcinogenicity studies had been performed with a soluble cobalt salt using a route relevant to occupational exposures. Groups of 50 male and 50 female F344/N rats and B6C3F1 mice were exposed to aerosols containing 0, 0.3, 1.0, or 3.0 mg/m3 cobalt sulfate hexahydrate, 6 h/day, 5 days/week, for 104 weeks. Survival and body weights of exposed rats and mice were generally unaffected by the exposures. In rats, proteinosis, alveolar epithelial metaplasia, granulomatous alveolar inflammation, and interstitial fibrosis were observed in the lung in all exposed groups. Nonneoplastic lesions of the nose and larynx were also attributed to exposure to all concentrations of cobalt sulfate. In 3.0 mg/m3 male rats and in female rats exposed to 1.0 or 3.0 mg/m3, the incidences of alveolar/bronchiolar neoplasms were increased over those in the control groups. Lung tumors occurred with significant positive trends in both sexes. The incidences of adrenal pheochromocytoma in 1.0 mg/m3 male rats and in 3.0 mg/m3 female rats were increased. Nonneoplastic lesions of the respiratory tract were less severe in mice than in rats. In mice, alveolar/bronchiolar neoplasms in 3.0 mg/m3 males and females were greater than those in the controls, and lung tumors occurred with significantly positive trends. Male mice had liver lesions consistent with a Helicobacter hepaticus infection. Incidences of liver hemangiosarcomas were increased in exposed groups of male mice; however, because of the infection, no conclusion could be reached concerning an association between liver hemangiosarcomas and cobalt sulfate. In summary, exposure to cobalt sulfate by inhalation

  20. Florida Red Tide: Inhalation Toxicity of Karenia brevis Extract in Rats

    OpenAIRE

    Benson, J M; Hahn, F F; Tibbetts, B.M.; Bowen, L.E.; March, T.F.; Langley, R. J.; Murray, T.F.; Bourdelais, A.J.; Naar, J.; Zaias, J.; Baden, D. G.

    2004-01-01

    Brevetoxins are neurotoxins produced by the marine dinoflagellate Karenia brevis. Histopathologic examination of marine mammals dying following repeated exposure of brevetoxins during red tide events suggests that the respiratory tract, nervous, hematopoietic, and immune systems are potential targets for toxicity in repeatedly exposed individuals. The purpose of this experiment was to evaluate the effects of repeated inhalation of K. brevis extract on these potential target systems in rats. M...

  1. Inhalation Injuries

    Science.gov (United States)

    ... you can inhale that can cause acute internal injuries. Particles in the air from fires and toxic ... and lung diseases worse. Symptoms of acute inhalation injuries may include Coughing and phlegm A scratchy throat ...

  2. Comparative pulmonary toxicity of inhaled metalworking fluids in rats and mice.

    Science.gov (United States)

    Ryan, Kristen R; Cesta, Mark F; Herbert, Ronald; Brix, Amy; Cora, Michelle; Witt, Kristine; Kissling, Grace; Morgan, Daniel L

    2017-05-01

    Metalworking fluids (MWFs) are complex formulations designed for effective lubricating, cooling, and cleaning tools and parts during machining operations. Adverse health effects such as respiratory symptoms, dermatitis, and cancer have been reported in workers exposed to MWFs. Several constituents of MWFs have been implicated in toxicity and have been removed from the formulations over the years. However, animal studies with newer MWFs demonstrate that they continue to pose a health risk. This investigation examines the hypothesis that unrecognized health hazards exist in currently marketed MWF formulations that are presumed to be safe based on hazard assessments of individual ingredients. In vivo 13-week inhalation studies were designed to characterize and compare the potential toxicity of four MWFs: Trim VX, Cimstar 3800, Trim SC210, and Syntilo 1023. Male and female Wistar Han rats or Fischer 344N/Tac rats and B6C3F1/N mice were exposed to MWFs via whole-body inhalation at concentrations of 0, 25, 50, 100, 200, or 400 mg/m(3) for 13 weeks, after which, survival, body and organ weights, hematology and clinical chemistry, histopathology, and genotoxicity were assessed following exposure. Although high concentrations were used, survival was not affected and toxicity was primarily within the respiratory tract of male and female rats and mice. Minor variances in toxicity were attributed to differences among species as well as in the chemical components of each MWF. Pulmonary fibrosis was present only in rats and mice exposed to Trim VX. These data confirm that newer MWFs have the potential to cause respiratory toxicity in workers who are repeatedly exposed via inhalation.

  3. Emergency planning and the acute toxic potency of inhaled ammonia.

    Science.gov (United States)

    Michaels, R A

    1999-08-01

    Ammonia is present in agriculture and commerce in many if not most communities. This report evaluates the toxic potency of ammonia, based on three types of data: anecdotal data, in some cases predating World War 1, reconstructions of contemporary industrial accidents, and animal bioassays. Standards and guidelines for human exposure have been driven largely by the anecdotal data, suggesting that ammonia at 5,000-10,000 parts per million, volume/volume (ppm-v), might be lethal within 5-10 min. However, contemporary accident reconstructions suggest that ammonia lethality requires higher concentrations. For example, 33,737 ppm-v was a 5-min zero-mortality value in a major ammonia release in 1973 in South Africa. Comparisons of secondary reports of ammonia lethality with original sources revealed discrepancies in contemporary sources, apparently resulting from failure to examine old documents or accurately translate foreign documents. The present investigation revealed that contemporary accident reconstructions yield ammonia lethality levels comparable to those in dozens of reports of animal bioassays, after adjustment of concentrations to human equivalent concentrations via U.S. Environmental Protection Agency (EPA) procedures. Ammonia levels potentially causing irreversible injury or impairing the ability of exposed people to escape from further exposure or from coincident perils similarly have been biased downwardly in contemporary sources. The EPA has identified ammonia as one of 366 extremely hazardous substances subject to community right-to-know provisions of the Superfund Act and emergency planning provisions of the Clean Air Act. The Clean Air Act defines emergency planning zones (EPZs) around industrial facilities exceeding a threshold quantity of ammonia on-site. This study suggests that EPZ areas around ammonia facilities can be reduced, thereby also reducing emergency planning costs, which will vary roughly with the EPZ radius squared.

  4. Mercury and Air Toxic Element Impacts of Coal Combustion By-Product Disposal and Utilizaton

    Energy Technology Data Exchange (ETDEWEB)

    David Hassett; Loreal Heebink; Debra Pflughoeft-Hassett; Tera Buckley; Erick Zacher; Mei Xin; Mae Sexauer Gustin; Rob Jung

    2007-03-31

    The University of North Dakota Energy & Environmental Research Center (EERC) conducted a multiyear study to evaluate the impact of mercury and other air toxic elements (ATEs) on the management of coal combustion by-products (CCBs). The ATEs evaluated in this project were arsenic, cadmium, chromium, lead, nickel, and selenium. The study included laboratory tasks to develop measurement techniques for mercury and ATE releases, sample characterization, and release experiments. A field task was also performed to measure mercury releases at a field site. Samples of fly ash and flue gas desulfurization (FGD) materials were collected preferentially from full-scale coal-fired power plants operating both without and with mercury control technologies in place. In some cases, samples from pilot- and bench-scale emission control tests were included in the laboratory studies. Several sets of 'paired' baseline and test fly ash and FGD materials collected during full-scale mercury emission control tests were also included in laboratory evaluations. Samples from mercury emission control tests all contained activated carbon (AC) and some also incorporated a sorbent-enhancing agent (EA). Laboratory release experiments focused on measuring releases of mercury under conditions designed to simulate CCB exposure to water, ambient-temperature air, elevated temperatures, and microbes in both wet and dry conditions. Results of laboratory evaluations indicated that: (1) Mercury and sometimes selenium are collected with AC used for mercury emission control and, therefore, present at higher concentrations than samples collected without mercury emission controls present. (2) Mercury is stable on CCBs collected from systems both without and with mercury emission controls present under most conditions tested, with the exception of vapor-phase releases of mercury exposed to elevated temperatures. (3) The presence of carbon either from added AC or from unburned coal can result in mercury

  5. Toxicity of Inorganic Mercury to Native Australian Grass Grown in Three Different Soils.

    Science.gov (United States)

    Mahbub, Khandaker Rayhan; Kader, Mohammed; Krishnan, Kannan; Labbate, Maurizio; Naidu, Ravi; Megharaj, Mallavarapu

    2017-06-01

    In this study, three native Australian grasses namely Iseilema membranaceum (Barcoo), Dichanthium sericeum (Queensland Blue) and Sporobolus africanus (Tussock) were grown in three different soils spiked with different concentrations of inorganic mercury and the root elongation was monitored up to 28 days following the germination. Results showed that mercury at certain concentrations significantly inhibited the root growth of all three tested native grasses grown in three soils, however, the toxicity was less in the soil with high organic carbon content and acidic pH. The calculated EC50 values ranged from 10 to 224 mg/kg total Hg in soil. However, the EC10 values indicated that existing guideline values for mercury may be of protective to the native Australian vegetation. Considering their tolerance to soil mercury, these grass species have the potential for their use in rehabilitation of mercury contaminated sites.

  6. Evaluation of the subacute and subchronic toxicity of inhaled EDS hydrotreated naphtha in the rat.

    Science.gov (United States)

    McKee, R H; Hinz, J P

    1987-07-01

    Inhalation studies were conducted to assess the subacute and subchronic toxicity of EDS hydrotreated naphtha (HN). In the subacute toxicity study, male and female Sprague-Dawley rats were exposed to various concentrations of HN vapor (0.2, 1.0, and 5.0 g/m3) 6 hr/day for 5 consecutive days. Following 2 recovery days, the animals were exposed for 4 additional days and then sacrificed on the 12th study day. In the subchronic toxicity study, a similar protocol was utilized; however, the animals were exposed 5 days/week for 13 weeks. Following a 2-week recovery period, the animals were sacrificed. Parameters examined in both studies included survival, growth, clinical observations, urinalysis, blood chemistry at necropsy, and microscopic examination of selected tissues. There was some evidence of systemic effects associated with repeated inhalation exposure to HN, although these effects were mild and were primarily confined to the high-exposure groups. The major systemic effect appeared to be renal toxicity in male rats as evidenced by increased urinary excretion of renal epithelial cells, creatinine, glucose, and protein and decreased urine osmolality. However, the absence of consistent pathologic changes in the kidneys of these animals suggested that the lesions were either slight or reversible during the 2-week recovery period.

  7. Airway irritation, inflammation, and toxicity in mice following inhalation of metal oxide nanoparticles

    DEFF Research Database (Denmark)

    Larsen, Søren T; Jackson, Petra; Poulsen, Steen S

    2016-01-01

    Metal oxide nanoparticles are used in a broad range of industrial processes and workers may be exposed to aerosols of the particles both during production and handling. Despite the widespread use of these particles, relatively few studies have been performed to investigate the toxicological effects...... in the airways following inhalation. In the present study, the acute (24 h) and persistent (13 weeks) effects in the airways after a single exposure to metal oxide nanoparticles were studied using a murine inhalation model. Mice were exposed 60 min to aerosols of either ZnO, TiO2, Al2O3 or CeO2 and the deposited...... doses in the upper and lower respiratory tracts were calculated. Endpoints were acute airway irritation, pulmonary inflammation based on analyses of bronchoalveolar lavage (BAL) cell composition, DNA damage assessed by the comet assay and pulmonary toxicity assessed by protein level in BAL fluid...

  8. Amelioration of Acute Mercury Toxicity by a Novel, Non-Toxic Lipid Soluble Chelator N,N′bis-(2-mercaptoethyl)isophthalamide: Effect on Animal Survival, Health, Mercury Excretion and Organ Accumulation

    OpenAIRE

    Clarke, David; Buchanan, Roger; Gupta, Niladri; Haley, Boyd

    2012-01-01

    The toxic effects of mercury are known to be complex with specific enzyme inhibitions and subsequent oxidative stress adding to the damaging effects. There are likely other factors involved, such as the development of impaired metal ion homeostasis and depletion of thiol and selenium based metabolites such as cysteine and selenium. Much of the toxicity of mercury occurs at the intracellular level via binding of Hg2+ to thiol groups in specific proteins. Therefore, amelioration of mercury toxi...

  9. Pulmonary toxicity of well-dispersed cerium oxide nanoparticles following intratracheal instillation and inhalation

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, Yasuo, E-mail: yasuom@med.uoeh-u.ac.jp; Izumi, Hiroto; Yoshiura, Yukiko; Tomonaga, Taisuke; Oyabu, Takako; Myojo, Toshihiko; Kawai, Kazuaki; Yatera, Kazuhiro [University of Occupational and Environmental Health (Japan); Shimada, Manabu; Kubo, Masaru [Hiroshima University (Japan); Yamamoto, Kazuhiro [National Institute of Advanced Industrial Science and Technology (AIST) (Japan); Kitajima, Shinichi [National Sanatorium Hoshizuka Keiaien (Japan); Kuroda, Etsushi [Osaka University, Laboratory of Vaccine Science, WPI Immunology Frontier Research Center (Japan); Kawaguchi, Kenji; Sasaki, Takeshi [National Institute of Advanced Industrial Science and Technology (AIST) (Japan)

    2015-11-15

    We performed inhalation and intratracheal instillation studies of cerium dioxide (CeO{sub 2}) nanoparticles in order to investigate their pulmonary toxicity, and observed pulmonary inflammation not only in the acute and but also in the chronic phases. In the intratracheal instillation study, F344 rats were exposed to 0.2 mg or 1 mg of CeO{sub 2} nanoparticles. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed from 3 days to 6 months following the instillation. In the inhalation study, rats were exposed to the maximum concentration of inhaled CeO{sub 2} nanoparticles (2, 10 mg/m{sup 3}, respectively) for 4 weeks (6 h/day, 5 days/week). The same endpoints as in the intratracheal instillation study were examined from 3 days to 3 months after the end of the exposure. The intratracheal instillation of CeO{sub 2} nanoparticles caused a persistent increase in the total and neutrophil number in BALF and in the concentration of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, chemokine for neutrophil, and heme oxygenase-1 (HO-1), an oxidative stress marker, in BALF during the observation time. The inhalation of CeO{sub 2} nanoparticles also induced a persistent influx of neutrophils and expression of CINC-1, CINC-2, and HO-1 in BALF. Pathological features revealed that inflammatory cells, including macrophages and neutrophils, invaded the alveolar space in both studies. Taken together, the CeO{sub 2} nanoparticles induced not only acute but also chronic inflammation in the lung, suggesting that CeO{sub 2} nanoparticles have a pulmonary toxicity that can lead to irreversible lesions.

  10. Developmental toxicity from exposure to various forms of mercury compounds in medaka fish (Oryzias latipes) embryos

    Science.gov (United States)

    Liu, Jie; Wei, Lixin; Jingfeng, Yang; Chernick, Melissa; Hinton, David E.

    2016-01-01

    This study examined developmental toxicity of different mercury compounds, including some used in traditional medicines. Medaka (Oryzias latipes) embryos were exposed to 0.001–10 µM concentrations of MeHg, HgCl2, α-HgS (Zhu Sha), and β-HgS (Zuotai) from stage 10 (6–7 hpf) to 10 days post fertilization (dpf). Of the forms of mercury in this study, the organic form (MeHg) proved the most toxic followed by inorganic mercury (HgCl2), both producing embryo developmental toxicity. Altered phenotypes included pericardial edema with elongated or tube heart, reduction of eye pigmentation, and failure of swim bladder inflation. Both α-HgS and β-HgS were less toxic than MeHg and HgCl2. Total RNA was extracted from survivors three days after exposure to MeHg (0.1 µM), HgCl2 (1 µM), α-HgS (10 µM), or β-HgS (10 µM) to examine toxicity-related gene expression. MeHg and HgCl2 markedly induced metallothionein (MT) and heme oxygenase-1 (Ho-1), while α-HgS and β-HgS failed to induce either gene. Chemical forms of mercury compounds proved to be a major determinant in their developmental toxicity. PMID:27635309

  11. Developmental toxicity from exposure to various forms of mercury compounds in medaka fish (Oryzias latipes embryos

    Directory of Open Access Journals (Sweden)

    Wu Dong

    2016-08-01

    Full Text Available This study examined developmental toxicity of different mercury compounds, including some used in traditional medicines. Medaka (Oryzias latipes embryos were exposed to 0.001–10 µM concentrations of MeHg, HgCl2, α-HgS (Zhu Sha, and β-HgS (Zuotai from stage 10 (6–7 hpf to 10 days post fertilization (dpf. Of the forms of mercury in this study, the organic form (MeHg proved the most toxic followed by inorganic mercury (HgCl2, both producing embryo developmental toxicity. Altered phenotypes included pericardial edema with elongated or tube heart, reduction of eye pigmentation, and failure of swim bladder inflation. Both α-HgS and β-HgS were less toxic than MeHg and HgCl2. Total RNA was extracted from survivors three days after exposure to MeHg (0.1 µM, HgCl2 (1 µM, α-HgS (10 µM, or β-HgS (10 µM to examine toxicity-related gene expression. MeHg and HgCl2 markedly induced metallothionein (MT and heme oxygenase-1 (Ho-1, while α-HgS and β-HgS failed to induce either gene. Chemical forms of mercury compounds proved to be a major determinant in their developmental toxicity.

  12. Mercury

    Science.gov (United States)

    ... as chlorine, sulfur, or oxygen, to form inorganic mercury compounds or "salts," which are usually white powders or ... Mercury also combines with carbon to make organic mercury compounds. The most common one, methylmercury, is produced mainly ...

  13. Mercury toxicity in two intertidal tropical marine molluscs

    OpenAIRE

    Ekanath, A.E.; Menon, N. R.

    1983-01-01

    Lethal and sub-lethal effects of mercury have been studied in Perna viridis and Modiolus carvalhoi. For P. viridis LC30 is 1.0 p.p.m. at 48 h and 0.23 p.p.m. at 96 h. Recorded LC50 values for M. carvalhoi are 0.5 p.p.m. and 0.19 p.p.m. at 48 h and 96 h respectively. The results document that these two species, although inhabiting the same area in the tidal belt, exhibit clear differences in mercury resistance. It is further shown that the duration of exposure affects mortality rates. In sub-l...

  14. 28-Day inhalation toxicity of graphene nanoplatelets in Sprague-Dawley rats.

    Science.gov (United States)

    Kim, Jin Kwon; Shin, Jae Hoon; Lee, Jong Seong; Hwang, Joo Hwan; Lee, Ji Hyun; Baek, Jin Ee; Kim, Tae Gyu; Kim, Boo Wook; Kim, Jin Sik; Lee, Gun Ho; Ahn, Kangho; Han, Sung Gu; Bello, Dhimiter; Yu, Il Je

    2016-09-01

    lymph nodes. The results of this 28-day graphene inhalation study suggest low toxicity and a NOAEL of no less than 1.88 mg/m(3).

  15. Toxicity of Volatile Methylated Species of Bismuth, Arsenic, Tin, and Mercury in Mammalian Cells In Vitro

    Directory of Open Access Journals (Sweden)

    E. Dopp

    2011-01-01

    Full Text Available The biochemical transformation of mercury, tin, arsenic and bismuth through formation of volatile alkylated species performs a fundamental role in determining the environmental processing of these elements. While the toxicity of inorganic forms of most of these compounds are well documented (e.g., arsenic, mercury and some of them are of relatively low toxicity (e.g., tin, bismuth, the more lipid-soluble organometals can be highly toxic. In the present study we investigated the cyto- and genotoxicity of five volatile metal(loid compounds: trimethylbismuth, dimethylarsenic iodide, trimethylarsine, tetramethyltin, and dimethylmercury. As far as we know, this is the first study investigating the toxicity of volatile metal(loid compounds in vitro. Our results showed that dimethylmercury was most toxic to all three used cell lines (CHO-9 cells, CaCo, Hep-G2 followed by dimethylarsenic iodide. Tetramethyltin was the least toxic compound; however, the toxicity was also dependend upon the cell type. Human colon cells (CaCo were most susceptible to the toxicity of the volatile compounds compared to the other cell lines. We conclude from our study that volatile metal(loid compounds can be toxic to mammalian cells already at very low concentrations but the toxicity depends upon the metal(loid species and the exposed cell type.

  16. Improved dispersion method of multi-wall carbon nanotube for inhalation toxicity studies of experimental animals.

    Science.gov (United States)

    Taquahashi, Yuhji; Ogawa, Yukio; Takagi, Atsuya; Tsuji, Masaki; Morita, Koichi; Kanno, Jun

    2013-01-01

    A multi-wall carbon nanotube (MWCNT) product Mitsui MWNT-7 is a mixture of dispersed single fibers and their agglomerates/aggregates. In rodents, installation of such mixture induces inflammatory lesions triggered predominantly by the aggregates/agglomerates at the level of terminal bronchiole of the lungs. In human, however, pulmonary toxicity induced by dispersed single fibers that reached the lung alveoli is most important to assess. Therefore, a method to generate aerosol predominantly consisting of dispersed single fibers without changing their length and width is needed for inhalation studies. Here, we report a method (designated as Taquann method) to effectively remove the aggregate/agglomerates and enrich the well-dispersed singler fibers in dry state without dispersant and without changing the length and width distribution of the single fibers. This method is base on two major concept; liquid-phase fine filtration and critical point drying to avoid re-aggregation by surface tension. MWNT-7 was suspended in Tert-butyl alcohol, freeze-and-thawed, filtered by a vibrating 25 µm mesh Metallic Sieve, snap-frozen by liquid nitrogen, and vacuum-sublimated (an alternative method to carbon dioxide critical point drying). A newly designed direct injection system generated well-dispersed aerosol in an inhalation chamber. The lung of mice exposed to the aerosol contained single fibers with a length distribution similar to the original and the Taquann-treated sample. Taquann method utilizes inexpensive materials and equipments mostly found in common biological laboratories, and prepares dry powder ready to make well-dispersed aerosol. This method and the chamber with direct injection system would facilitate the inhalation toxicity studies more relevant to human exposure.

  17. Comparison of sarin and cyclosarin toxicity by subcutaneous, intravenous and inhalation exposure in Gottingen minipigs.

    Science.gov (United States)

    Hulet, Stanley W; Sommerville, Douglas R; Miller, Dennis B; Scotto, Jacqueline A; Muse, William T; Burnett, David C

    2014-02-01

    Sexually mature male and female Gottingen minipigs were exposed to various concentrations of GB and GF vapor via whole-body inhalation exposures or to liquid GB or GF via intravenous or subcutaneous injections. Vapor inhalation exposures were for 10, 60 or 180 min. Maximum likelihood estimation was used to calculate the median effect levels for severe effects (ECT50 and ED50) and lethality (LCT50 and LD50). Ordinal regression was used to model the concentration × time profile of the agent toxicity. Contrary to that predicted by Haber's rule, LCT50 values increased as the duration of the exposures increased for both nerve agents. The toxic load exponents (n) were calculated to be 1.38 and 1.28 for GB and GF vapor exposures, respectively. LCT50 values for 10-, 60- and 180-min exposures to vapor GB in male minipigs were 73, 106 and 182 mg min/m(3), respectively. LCT50 values for 10-, 60 - and 180-min exposures to vapor GB in female minipigs were 87, 127 and 174 mg min/m(3), respectively. LCT50 values for 10-, 60- and 180-min exposures to vapor GF in male minipigs were 218, 287 and 403 mg min/m(3), respectively. LCT50 values for 10-, 60- and 180-min exposures in female minipigs were 183, 282 and 365 mg min/m(3), respectively. For GB vapor exposures, there was a tenuous gender difference which did not exist for vapor GF exposures. Surprisingly, GF was 2-3 times less potent than GB via the inhalation route of exposure regardless of exposure duration. Additionally GF was found to be less potent than GB by intravenous and subcutaneous routes.

  18. Chest radiographic and CT features of acute inhaled mercury poisoning%急性吸入性汞中毒胸部X线及CT表现

    Institute of Scientific and Technical Information of China (English)

    刘雨峰

    2012-01-01

    Objective To analyze chest radiographic and CT features of acute inhaled mercury poisoning. Methods 23 cases with high concentration of mercury vapour inhaled acutely were included in this study. Among them, 81 cases underwent chest radio-graphics (61 times) and 11 cases underwent CT scanning(17 times). Radiographic and CT features were analysed. Results Chest radiographs showed pneumonia in 10 cases, the lesions appeared as multiple and scattered patchy high density in bilateral lung field with obscure border, and 3 cases combined with emphysema. There were 7 cases of interstitial pneumonia, radiographs showed lung markings increased and disorder, patchy, strip and gridding high dense shadows. 6 cases had toxic bubble pulmonary edema, which presented as large patchy dense shadows, and 4 cases of interstitial pulmonary edema, K's A,B lines were seen. On CT images, pneumonia appeared as multiple and scattered patchy shadows in bilateral lung field with bullous emphysemas which were low dense thin-wall bubbly shadows. Interstitial pneumonia appeared as lung weight lung markings in creased and blurred, resulted in massive, stripe net-like dense shadows with exudative changes around the lesions. Bullous pulmonary edema appeared as large patchy or butterfly wing-like dense shadow with undefinitive borders. Conclusion The chest X-ray and CT manifestations arc of certain characteristics in acute inhalation of mercury-induced pneumonia, combined with the clinical history and laboratory examination the diagnosis may be done.%目的 分析急性吸入性汞中毒性肺炎胸部X线及CT表现.方法 23例急性吸入性汞中毒患者,拍摄胸部平片61次,其中11例行胸部CT扫描17次,分析其X线及CT表现.结果 23例入院时X线片示汞毒性实质性肺炎10例,表现为双肺野多发片状密度增高影,边缘模糊,散在分布,3例伴有泡性肺气肿.汞毒性肺间质性炎症7例,表现为肺纹理增重模糊及紊乱,呈

  19. Mercury

    Science.gov (United States)

    Mercury is an element that is found in air, water and soil. It has several forms. Metallic mercury is a shiny, silver-white, odorless liquid. If ... with other elements to form powders or crystals. Mercury is in many products. Metallic mercury is used ...

  20. Per- and polyfluoro toxicity (LC(50) inhalation) study in rat and mouse using QSAR modeling.

    Science.gov (United States)

    Bhhatarai, Barun; Gramatica, Paola

    2010-03-15

    Fully or partially fluorinated compounds, known as per- and polyfluorinated chemicals are widely distributed in the environment and released because of their use in different household and industrial products. Few of these long chain per- and polyfluorinated chemicals are classified as emerging pollutants, and their environmental and toxicological effects are unveiled in the literature. This has diverted the production of long chain compounds, considered as more toxic, to short chains, but concerns regarding the toxicity of both types of per- and polyfluorinated chemicals are alarming. There are few experimental data available on the environmental behavior and toxicity of these compounds, and moreover, toxicity profiles are found to be different for the types of animals and species used. Quantitative structure-activity relationship (QSAR) is applied to a combination of short and long chain per- and polyfluorinated chemicals, for the first time, to model and predict the toxicity on two species of rodents, rat (Rattus) and mouse (Mus), by modeling inhalation (LC(50)) data. Multiple linear regression (MLR) models using the ordinary-least-squares (OLS) method, based on theoretical molecular descriptors selected by genetic algorithm (GA), were used for QSAR studies. Training and prediction sets were prepared a priori, and these sets were used to derive statistically robust and predictive (both internally and externally) models. The structural applicability domain (AD) of the model was verified on a larger set of per- and polyfluorinated chemicals retrieved from different databases and journals. The descriptors involved, the similarities, and the differences observed between models pertaining to the toxicity related to the two species are discussed. Chemometric methods such as principal component analysis (PCA) and multidimensional scaling (MDS) were used to select most toxic compounds from those within the AD of both models, which will be subjected to experimental tests

  1. Mercury Toxicity on Sodium Pump and Organoseleniums Intervention: A Paradox

    Directory of Open Access Journals (Sweden)

    Ige Joseph Kade

    2012-01-01

    Full Text Available Mercury is an environmental poison, and the damage to living system is generally severe. The severity of mercury poisoning is consequent from the fact that it targets the thiol-containing enzymes, irreversibly oxidizing their critical thiol groups, consequently leading to an inactivation of the enzyme. The Na+/K+-ATPase is a sulfhydryl protein that is sensitive to Hg2+ assault. On the other hand, organoseleniums are a class of pharmacologically promising compounds with potent antioxidant effects. While Hg2+ oxidizes sulfhydryl groups of Na+/K+-ATPase under in vitro and in vivo conditions, the organoselenium compounds inhibit Na+/K+-ATPase in vitro but enhance its activities under in vivo conditions with concomitant increase in the level of endogenous thiols. Paradoxically, it appears that these two thiol oxidants can be used to counteract one another under in vivo conditions, and this hypothesis serves as the basis for this paper.

  2. Toxicity evaluation of petroleum blending streams: inhalation subchronic toxicity/neurotoxicity study of a light alkylate naphtha distillate in rats.

    Science.gov (United States)

    Schreiner, C; Lapadula, E; Breglia, R; Bui, Q; Burnett, D; Koschier, F; Podhasky, P; White, R; Mandella, R; Hoffman, G

    1998-10-23

    A 13-wk inhalation study was conducted with Sprague-Dawley CD rats (12/sex/group) were exposed by inhalation for 13 weeks to a light alkylate naphtha distillate (LAND-2, C4-C10; average molecular weight 89.2) at actual average concentrations of 0 (room air), 668, 2220, or 6646 ppm, 6 h/d, 5 d/wk; 12 additional rats/sex in the control and high dose groups were held after final exposure for a 4-wk recovery period. The highest exposure concentration was 75% of the lower explosive limit. Standard parameters of subchronic toxicity were measured throughout the study; at necropsy, organs were weighed and tissues processed for microscopic evaluation. Neurotoxicity evaluations consisted of motor activity (MA) and a functional operational battery (FOB) measured pretest, during 5, 9, and 14 wk of the study, and after the 4-wk recovery period. Whole-body perfusion and microscopic examination of selected organs and nervous tissue from the control and high dose rats were conducted at the end of exposure. No test-related mortality or effects on physical signs, body weight, or food consumption were observed. Statistically significant increases in absolute and relative kidney weights in high-exposure males correlated with microscopically observed hyaline droplet formation and renal nephropathy, effects in male rats that are not toxicologically significant for humans. Increased liver weights in both sexes at the highest dose had no microscopic correlate and appeared reversible after the 4-wk recovery period. Exposure to LAND-2 at any dose did not produce neurotoxicity measured by MA, FOB, or neuropathology. The no-observed-effects level (NOEL) for LAND-2 was 2220 ppm for subchronic toxicity and > or =26646 ppm for neurotoxicity.

  3. Lack of selective developmental toxicity of three butanol isomers administered by inhalation to rats.

    Science.gov (United States)

    Nelson, B K; Brightwell, W S; Khan, A; Burg, J R; Goad, P T

    1989-04-01

    As part of an ongoing study of the developmental toxicology of industrial alcohols, this report presents the results of the teratology assessments of 1-butanol, 2-butanol, and t-butanol administered by inhalation to rats. Groups of approximately 15 Sprague-Dawley rats were exposed at 8000, 6000, 3500, or 0 ppm 1-butanol, 7000, 5000, 3500, or 0 ppm 2-butanol, or 5000, 3500, 2000, or 0 ppm t-butanol for 7 hr/day on Gestation Days 1-19 (sperm = 0). In each case, the highest concentration was selected to produce maternal toxicity. Dams were sacrificed on Gestation Day 20, and fetuses were individually weighed, tagged, and examined for external malformations. One-half of the fetuses were stained and examined for skeletal abnormalities, and the other half were examined for visceral defects using the Wilson technique. For each butanol isomer examined, the highest concentration (and the intermediate in some cases) was maternally toxic, as manifest by reduced weight gain and feed intake. Even at a maternally toxic dose, and in spite of a dose-dependent reduction in fetal weights for each isomer, the only teratogenicity observed was a slight increase in skeletal malformations (primarily rudimentary cervical ribs), seen with the highest concentration of 1-butanol. Thus, although teratogenicity was observed at 8000 ppm 1-butanol, and developmental toxicity was observed with each of the butyl alcohol isomers studied, concentrations 50 times the current permissible exposure limits for these three butanol isomers do not produce teratogenicity in rats.

  4. Size fractionation in mercury-bearing airborne particles (HgPM 10) at Almadén, Spain: Implications for inhalation hazards around old mines

    Science.gov (United States)

    Moreno, Teresa; Higueras, Pablo; Jones, Tim; McDonald, Iain; Gibbons, Wes

    Almadén has a >2000y mining history and an unprecedented legacy of mercury contamination. Resuspended airborne particles were extracted from mine waste (Las Cuevas), retort site soil (Almadenejos), and urban car park dust (Almadén), separated into fine (PM 10) and coarse (PM >10 μm ) fractions, analysed for mercury using ICP-MS, and individual HgPM characterised using SEM. Cold extractable mercury concentrations in PM 10 range from 100 to 150 μg g -1 (car parks), to nearly 6000 μg g -1 (mine waste), reaching a world record of 95,000 μg g -1 above the abandoned retort at Almadenejos where ultrafine HgPM have pervaded the brickwork and soil and entered the food chain: edible wild asparagus stem material from here contains 35-65 μg g -1 Hg, and pig hair from animals living, inhaling and ingesting HgPM 10 at the site yielded 8-10 μg g -1. The PM 10 fraction (dusts easily wind transported and deeply inhaled) contains much more mercury than the coarser fraction. The contribution of HgPM 10 to ecosystem contamination and potential human health effects around old mercury mines has been underestimated.

  5. Interspecific and intraspecific variation in selenium:mercury molar ratios in saltwater fish from the Aleutians: Potential protection on mercury toxicity by selenium

    Science.gov (United States)

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Donio, Mark; Pittfield, Taryn

    2014-01-01

    A number of factors affect the consumption risk from mercury in fish, including mercury levels, seasonal patterns of mercury concentrations, human consumption patterns, and sensitive populations (e.g. pregnant women, fetuses, young children, and yet unknown genetic factors). Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for saltwater fish. We examine levels of mercury and selenium in several species of fish and seabirds from the Aleutians (Alaska), determine selenium:mercury molar ratios, and examine species-specific and individual variation in the ratios as a means of exploring the use of the ratio in risk assessment and risk management. Variation among species was similar for mercury and selenium. There was significant inter-specific and intraspecific variation in selenium:mercury molar ratios for fish, and for birds. The mean selenium:mercury molar ratios for all fish and bird species were above 1, meaning there was an excess of selenium relative to mercury. It has been suggested that an excess of selenium confers some protective advantage for salt water fish, although the degree of excess necessary is unclear. The selenium:mercury molar ratio was significantly correlated negatively with total length for most fish species, but not for dolly varden. Some individuals of Pacific cod, yellow irish lord, rock greenling, Pacific halibut, dolly varden, and to a lesser extent, flathead sole, had selenium:mercury ratios below 1. No bird muscle had an excess of mercury (ratio below 1), and only glaucous-winged gull and pigeon guillemot had ratios between 1 and 5. There was a great deal of variation in selenium:mercury molar ratios within fish species, and within bird species, making it difficult and impractical to use these ratios in risk assessment or management, for fish advisories, or for consumers, particularly given the difficulty of interpreting the ratios. PMID:22664537

  6. Oral and intramuscular toxicity of inorganic and organic mercury chloride to growing quail

    Science.gov (United States)

    Hill, E.F.; Soares, J.H.

    1987-01-01

    The lethal toxicity of inorganic (HgCl2) and organic (CH3HgCl) mercury chloride was compared for Coturnix (Japanese quail, Coturnix japonica) of different ages from hatch through adulthood by single-dose acute oral and intramuscular injections and by a 5-d dietary trial. Sublethal mercury toxicity was studied by evaluation of plasma and brain cholinesterase activity. CH3HgCl was more toxic than HgCl2 in all tests at each age tested. LD50s consistently increased over the first 4 wk for both acute methods and both mercurials and then stabilized. The striking difference between single-dose acute and 5-d dietary tests was that CH3HgCl averaged about twice as toxic as HgCl2 by both acute methods, compared to 100 times as toxic by the dietary method. For example, at 2 wk of age, the oral LD50s for CH3HgCl and HgCl2 were 18 and 42 mg/kg and the dietary LC50s were 47 and 5086 ppm. When birds were fed HgCl2 and developed clinical signs of intoxication, they could recover once treatment was withdrawn; however, on CH3HgCl, clinical signs often commenced after treatment was withdrawn, and then actually intensified for several days and culminated in death.

  7. Multisite carcinogenicity and respiratory toxicity of inhaled 1-bromopropane in rats and mice.

    Science.gov (United States)

    Morgan, Daniel L; Nyska, Abraham; Harbo, Sam Jens; Grumbein, Sondra L; Dill, Jeffrey A; Roycroft, Joseph H; Kissling, Grace E; Cesta, Mark F

    2011-10-01

    Two-year 1-bromopropane (1-BP) inhalation studies were conducted because of the potential for widespread exposure, the lack of chronic toxicity and carcinogenicity data, and the known carcinogenicity of structurally related compounds. Male and female F344/N rats and B6C3F1/N mice were exposed by inhalation to 0, 62.5 (mice only), 125, 250, or 500 (rats only) ppm 1-BP for 6 hr/day, 5 days/week for 105 weeks. Exposure of male and female rats to 1-BP resulted in significantly increased incidences of adenomas of the large intestine and skin neoplasms. In male rats, the incidence of malignant mesothelioma of the epididymis was statistically significantly increased at 500 ppm, but the biological significance of this common lesion is unclear. Incidences of pancreatic islet adenoma in male rats were significantly increased at all concentrations relative to concurrent controls but were within the historical control range for inhalation studies. There was no evidence of carcinogenic activity of 1-BP in male B6C3F1 mice; however, significantly increased incidences of alveolar/bronchiolar neoplasms of the lung were present in female mice. Exposure to 1-BP also resulted in increased incidences of nonneoplastic lesions in the nose of rats and mice, the larynx of rats and male mice, the trachea of female rats and male and female mice, and the lungs of mice. Inflammatory lesions with Splendore Hoeppli (S-H) material were present primarily in the nose and skin of exposed male and female rats, indicating that 1-BP caused immunosuppression.

  8. Toxic effect in the lungs of rats after inhalation exposure to benzalkonium chloride

    Directory of Open Access Journals (Sweden)

    Radosław Świercz

    2013-08-01

    Full Text Available Background: Benzalkonium chloride (BAC is a quaternary ammonium compound (QAC toxic to microorganisms. Inhalation is one of the major possible routes of human exposure to BAC. Materials and Methods: Experiments were performed on female Wistar rats. The rats were exposed to aerosol of BAC water solution at the target concentration of 0 (control group and 35 mg/m3 for 5 days (6 h/day and, after a 2-week interval, the animals were challenged (day 21 with BAC aerosol at the target concentration of 0 (control group and 35 mg/m3 for 6 h. Results: Compared to the controls, the animals exposed to BAC aerosol were characterized by lower food intake and their body weight was significantly smaller. As regards BAC-exposed group, a significant increase was noted in relative lung mass, total protein concentration, and MIP-2 in BALF both directly after the termination of the exposure and 18 h afterwards. Significantly higher IL-6 and IgE concentrations in BALF and a decrease in the CC16 concentration in BALF were found in the exposed group immediately after the exposure. The leukocyte count in BALF was significantly higher in the animals exposed to BAC aerosol compared to the controls. In the lungs of rats exposed to BAC the following effects were observed: minimal perivascular, interstitial edema, focal aggregates of alveolar macrophages, interstitial mononuclear cell infiltrations, thickened alveolar septa and marginal lipoproteinosis. Conclusion: Inhalation of BAC induced a strong inflammatory response and a damage to the blood-air barrier. Reduced concentrations of CC16, which is an immunosuppressive and anti-inflammatory protein, in combination with increased IgE concentrations in BALF may be indicative of the immuno-inflammatory response in the animals exposed to BAC aerosol by inhalation. Histopathological examinations of tissue samples from the BAC-exposed rats revealed a number of pathological changes found only in the lungs.

  9. THE STUDY OF THE TOXIC EFFECTS OF MERCURY-II-CHLORIDE TO CHUB Leuciscus cephalus (L., 1758)

    OpenAIRE

    Gül, Ali; Yilmaz, Mehmet; SELVİ, Mahmut

    2010-01-01

    ABSTRACT Mercury is one of the most harmful heavy metals, present in many aquatic media. This study was aimed to determine the acute toxicity of  mercury-II-chloride and behavioral changes in   Leuciscus cephalus (L., 1758). Leuciscus cephalus were selected for the bioassays experiments and caught in Kirmir branch of Sakarya river. Behavioral changes at each mercury-II-chloride concentration were recorded. The experiments were repeated 3 times. Water temperature was...

  10. Component-specific toxic concerns of the inhalable fraction of urban road dust.

    Science.gov (United States)

    Potgieter-Vermaak, S; Rotondo, G; Novakovic, V; Rollins, S; Van Grieken, R

    2012-12-01

    Continuous global urbanisation causes an ever-growing ecological footprint of pollution. Road dust (RD), one of these pollutants, poses a health concern due to carcinogenic and toxic components potentially present in the micron-sized fractions. The literature reports on the concentrations of trace, toxic metals and metalloids present in RD (Hooker and Nathanail in Chem Geol 226:340-351, 2006), but the literature on its molecular composition is limited. Recent reports on the bioaccessibility of platinum group metals are also reported (Colombo et al. in Chem Geol 226:340-351, 2008). In vitro and animal toxicological studies confirmed that the chemical composition of inhaled particles plays a major role in its toxic, genotoxic and carcinogenic mechanisms, but the component-specific toxic effects are still not understood. Particle-bound airborne transition metals can also lead to the production of reactive oxygen species in lung tissue; a special concern amongst particularly susceptible cohorts (children and elderly). The characterisation of the molecular composition of the fine fraction is evidently of importance for public health. During a pilot study, partially characterised size-fractioned RD samples (Barrett et al. in Eviron Sci Technol 44:2940-2946, 2010) were analysed for their elemental concentration using X-ray fluorescence spectrometry and inductively coupled plasma mass spectrometry. In addition, separately dispersed particles (200 particles per size fraction) were analysed individually by means of computer-controlled electron probe X-ray micro-analysis (CC-EPXMA) and their molecular structure probed by studying elemental associations. These were correlated with micro-Raman spectroscopy (MRS) results. It was found that the fine fraction (50 % association of Cr-rich particles with Pb, and the MRS data showed that the Cr was mostly present as lead chromate and therefore in the Cr(VI) oxidation state. Concentrations of both Pb and Cr decreased substantially

  11. Human Exposure and Health Effects of Inorganic and Elemental Mercury

    Science.gov (United States)

    Zheng, Wei

    2012-01-01

    Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety. PMID:23230464

  12. An in vitro Method for Predicting Inhalation Toxicity of Impregnation Spray Products

    DEFF Research Database (Denmark)

    Sørli, Jorid B.; Hansen, Jitka S.; Nørgaard, Asger Wisti

    2015-01-01

    Impregnation spray products are used for making surfaces water and dirt repellent. The products are composed of one or more active film-forming components dissolved or suspended in an appropriate solvent mixture. Exposure to impregnation spray products may cause respiratory distress and new cases...... of the inhalation toxicity of impregnation spray products and thus may reduce the need for animal testing....... of this study was to evaluate whether disruption of the pulmonary surfactant film can be used as a predictor of the toxic effects in vivo. Nine impregnation products with various chemical compositions were selected for testing and the main constituents of each product, e.g., solvents, co-solvents and film...... and in vivo. The true positive rate of the in vitro method was 100%, i.e. the test could correctly identify all products with toxic effects in vivo, the true negative rate was 40%. Investigation of inhibition of the pulmonary surfactant system, e.g. by capillary surfactometry, was found useful for evaluation...

  13. Toxic effects of mercuric chloride, methylmercuric chloride, and Emisan 6 (an organic mercurial fungicide) on ovarian recrudescence in the catfish

    Energy Technology Data Exchange (ETDEWEB)

    Kirubagaran, R.; Joy, K.P.

    1988-12-01

    Mercurial toxicity in fishes has been focused mainly on tissue uptake and subcellular distribution, nephrotoxicity, development, hatching and survivability of young ones and teratology. Very few studies have been attempted to investigate Hg toxicity on gonadal activity of fishes throughout the breeding season. In a previous investigation the authors have studied the toxic effects of mercuric chloride (HgCl/sub 2/), methylmercuric chloride (CH/sub 3/HgCl) and emisan 6 (an alkoxyalkyl fungicide) on the survival and histology of the kidney of the catfish, Clarias batrachus. The present report deals with toxic effects of these mercurials on ovarian recrudescence in the catfish, an economically important species in the subcontinent.

  14. Impact of hepatic P450-mediated biotransformation on the disposition and respiratory tract toxicity of inhaled naphthalene.

    Science.gov (United States)

    Kovalchuk, Nataliia; Kelty, Jacklyn; Li, Lei; Hartog, Matthew; Zhang, Qing-Yu; Edwards, Patricia; Van Winkle, Laura; Ding, Xinxin

    2017-08-15

    We determined whether a decrease in hepatic microsomal cytochrome P450 activity would impact lung toxicity induced by inhalation exposure to naphthalene (NA), a ubiquitous environmental pollutant. The liver-Cpr-null (LCN) mouse showed decreases in microsomal metabolism of NA in liver, but not lung, compared to wild-type (WT) mouse. Plasma levels of NA and NA-glutathione conjugates (NA-GSH) were both higher in LCN than in WT mice after a 4-h nose-only NA inhalation exposure at 10ppm. Levels of NA were also higher in lung and liver of LCN, compared to WT, mice, following exposure to NA at 5 or 10ppm. Despite the large increase in circulating and lung tissue NA levels, the level of NA-GSH, a biomarker of NA bioactivation, was either not different, or only slightly higher, in lung and liver tissues of LCN mice, relative to that in WT mice. Furthermore, the extent of NA-induced acute airway injury, judging from high-resolution lung histopathology and morphometry at 20h following NA exposure, was not higher, but lower, in LCN than in WT mice. These results, while confirming the ability of extrahepatic organ to bioactivate inhaled NA and mediate NA's lung toxicity, suggest that liver P450-generated NA metabolites also have a significant, although relatively small, contribution to airway toxicity of inhaled NA. This hepatic contribution to the airway toxicity of inhaled NA may be an important risk factor for individuals with diminished bioactivation activity in the lung. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Acute pulmonary toxicity following inhalation exposure to aerosolized VX in anesthetized rats.

    Science.gov (United States)

    Peng, Xinqi; Perkins, Michael W; Simons, Jannitt; Witriol, Alicia M; Rodriguez, Ashley M; Benjamin, Brittany M; Devorak, Jennifer; Sciuto, Alfred M

    2014-06-01

    This study evaluated acute toxicity and pulmonary injury in rats at 3, 6 and 24 h after an inhalation exposure to aerosolized O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX). Anesthetized male Sprague-Dawley rats (250-300 g) were incubated with a glass endotracheal tube and exposed to saline or VX (171, 343 and 514 mg×min/m³ or 0.2, 0.5 and 0.8 LCt₅₀, respectively) for 10 min. VX was delivered by a small animal ventilator at a volume of 2.5 ml × 70 breaths/minute. All VX-exposed animals experienced a significant loss in percentage body weight at 3, 6, and 24 h post-exposure. In comparison to controls, animals exposed to 514 mg×min/m³ of VX had significant increases in bronchoalveolar lavage (BAL) protein concentrations at 6 and 24 h post-exposure. Blood acetylcholinesterase (AChE) activity was inhibited dose dependently at each of the times points for all VX-exposed groups. AChE activity in lung homogenates was significantly inhibited in all VX-exposed groups at each time point. All VX-exposed animals assessed at 20 min and 3, 6 and 24 h post-exposure showed increases in lung resistance, which was prominent at 20 min and 3 h post-exposure. Histopathologic evaluation of lung tissue of the 514 mg×min/m³ VX-exposed animals at 3, 6 and 24 h indicated morphological changes, including perivascular inflammation, alveolar exudate and histiocytosis, alveolar septal inflammation and edema, alveolar epithelial necrosis, and bronchiolar inflammatory infiltrates, in comparison to controls. These results suggest that aerosolization of the highly toxic, persistent chemical warfare nerve agent VX results in acute pulmonary toxicity and lung injury in rats.

  16. Amelioration of Acute Mercury Toxicity by a Novel, Non-Toxic Lipid Soluble Chelator N,N'bis-(2-mercaptoethyl)isophthalamide: Effect on Animal Survival, Health, Mercury Excretion and Organ Accumulation.

    Science.gov (United States)

    Clarke, David; Buchanan, Roger; Gupta, Niladri; Haley, Boyd

    2012-01-01

    The toxic effects of mercury are known to be complex with specific enzyme inhibitions and subsequent oxidative stress adding to the damaging effects. There are likely other factors involved, such as the development of impaired metal ion homeostasis and depletion of thiol and selenium based metabolites such as cysteine and selenium. Much of the toxicity of mercury occurs at the intracellular level via binding of Hg(2+) to thiol groups in specific proteins. Therefore, amelioration of mercury toxicity by the use of chelation would likely be enhanced by the use of a chelator that could cross the cell membrane and the blood brain barrier. It would be most favorable if this compound was of low toxicity, had appropriate pharmacokinetics, bound and rendered mercury cation non-toxic and had antioxidant properties. Herein we report on such a chelator, N,N'-bis(2-mercaptoethyl)isophthalamide (NBMI), and, using an animal model, show that it prevented the toxic effects associated with acute exposure induced by injected mercury chloride.

  17. Assessment of Pulmonary Toxicity Induced by Inhaled Toner with External Additives

    Directory of Open Access Journals (Sweden)

    Taisuke Tomonaga

    2017-01-01

    Full Text Available We investigated the harmful effects of exposure to a toner with external additives by a long-term inhalation study using rats, examining pulmonary inflammation, oxidative stress, and histopathological changes in the lung. Wistar rats were exposed to a well-dispersed toner (mean of MMAD: 2.1 μm at three mass concentrations of 1, 4, and 16 mg/m3 for 22.5 months, and the rats were sacrificed after 6 months, 12 months, and 22.5 months of exposure. The low and medium concentrations did not induce statistically significant pulmonary inflammation, but the high concentration did, and, in addition, a histopathological examination showed fibrosis in the lung. Although lung tumor was observed in one sample of high exposure for 22.5 months, the cause was not statistically significant. On the other hand, a persistent increase in 8-OHdG was observed in the high exposure group, indicating that DNA damage by oxidative stress with persistent inflammation leads to the formation of tumorigenesis. The results of our studies show that toners with external additives lead to pulmonary inflammation, oxidative stress, and fibrosis only at lung burdens beyond overload. These data suggest that toners with external additives may have low toxicity in the lung.

  18. Health assessment of gasoline and fuel oxygenate vapors: subchronic inhalation toxicity.

    Science.gov (United States)

    Clark, Charles R; Schreiner, Ceinwen A; Parker, Craig M; Gray, Thomas M; Hoffman, Gary M

    2014-11-01

    Sprague Dawley rats were exposed via inhalation to vapor condensates of either gasoline or gasoline combined with various fuel oxygenates to assess whether their use in gasoline influences the hazard of evaporative emissions. Test substances included vapor condensates prepared from an EPA described "baseline gasoline" (BGVC), or gasoline combined with methyl tertiary butyl ether (G/MTBE), ethyl t-butyl ether (G/ETBE), t-amyl methyl ether (G/TAME), diisopropyl ether (G/DIPE), ethanol (G/EtOH), or t-butyl alcohol (G/TBA). Target concentrations were 0, 2000, 10,000 or 20,000mg/m(3) and exposures were for 6h/day, 5days/week for 13weeks. A portion of the animals were maintained for a four week recovery period to determine the reversibility of potential adverse effects. Increased kidney weight and light hydrocarbon nephropathy (LHN) were observed in treated male rats in all studies which were reversible or nearly reversible after 4weeks recovery. LHN is unique to male rats and is not relevant to human toxicity. The no observed effect level (NOAEL) in all studies was 10,000mg/m(3), except for G/MTBE (gasoline alone.

  19. Studies on the prenatal toxicity of toluene in rabbits following inhalation exposure and proposal of a pregnancy guidance value

    Energy Technology Data Exchange (ETDEWEB)

    Klimisch, H.J.; Hellwig, J. (BASF AG, Ludwigshafen am Rhein (Germany). Abt. fuer Toxikologie); Hofmann, A. (Merck (E.), Darmstadt (Germany). Inst. fuer Toxikologie)

    1992-07-01

    Prenatal toxicity of toluene was determined in two separate studies by inhalation exposure of Himalayan rabbits. In the first study 15 artificially inseminated females per group were exposed to 30, 100, or 300 ppm and in the second study 20 artificially inseminated females per group inhaled 100 or 500 ppm. In each case the rabbits were exposed for 6 hours per day from day 6 post-insemination (p.i.) to day 18 p.i. The respective controls inhaled conditioned clean air under the same exposure conditions. No signs of maternal toxicity were observed. All data obtained on gestational parameters were found to be within the variation range reported for this rabbit strain. The fetal external, soft tissue and skeletal findings, were seen in toluene exposed fetuses in a frequency similar to the corresponding and/or historical controls. Differences observed between the groups were not concentration dependent and were considered incidental rather than compound related. Therefore, toluene was not embryotoxic, fetotoxic, or teratogenic for rabbits exposed during the period of organogenesis. The highest concentration tested under these conditions (500 ppm) was found to be a no-observable-adverse-effect level (NOAEL) for both the adult and the fetal Himalayan rabbit. Based on these and previous results of animal studies of prenatal toxicity, a safety or uncertainty factor approach is considered for setting limits of exposure for women at workplaces. A pregnancy guidance value of 20 ppm is proposed. (orig.).

  20. Accumulation, subcellular distribution and toxicity of inorganic mercury and methylmercury in marine phytoplankton

    Energy Technology Data Exchange (ETDEWEB)

    Wu Yun [Division of Life Science, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong); Wang Wenxiong, E-mail: wwang@ust.hk [Division of Life Science, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong)

    2011-10-15

    We examined the accumulation, subcellular distribution, and toxicity of Hg(II) and MeHg in three marine phytoplankton (the diatom Thalassiosira pseudonana, the green alga Chlorella autotrophica, and the flagellate Isochrysis galbana). For MeHg, the inter-species toxic difference could be best interpreted by the total cellular or intracellular accumulation. For Hg(II), both I. galbana and T. pseudonana exhibited similar sensitivity, but they each accumulated a different level of Hg(II). A higher percentage of Hg(II) was bound to the cellular debris fraction in T. pseudonana than in I. galbana, implying that the cellular debris may play an important role in Hg(II) detoxification. Furthermore, heat-stable proteins were a major binding pool for MeHg, while the cellular debris was an important binding pool for Hg(II). Elucidating the different subcellular fates of Hg(II) and MeHg may help us understand their toxicity in marine phytoplankton at the bottom of aquatic food chains. - Highlights: > The inter-species toxic difference of methylmercury in marine phytoplankton can be explained by its total cellular or intracellular accumulation. > The inter-species toxic difference of inorganic mercury in marine phytoplankton can be explained by its subcellular distribution. > Heat-stable protein was a major binding pool for MeHg, while the cellular debris was an important binding pool for Hg(II). - The inter-species difference in methylmercury and inorganic mercury toxicity in phytoplankton can be explained by cellular accumulation and subcellular distribution.

  1. Termómetros de mercurio, aún tóxicos aún presentes Mercury thermometers, still toxic, still present

    Directory of Open Access Journals (Sweden)

    A. Souto

    2012-12-01

    Full Text Available Los termómetros de mercurio han sido y son, a pesar de la prohibición de su fabricación, una de las principales fuentes de exposición en la edad pediátrica al mercurio (Hg elemental en nuestro medio. La toxicidad producida por el Hg elemental depende de la vía de exposición y de la duración de la misma. La exposición a través del tracto digestivo no produce prácticamente toxicidad, pero la inoculación subcutánea o endovenosa y la inhalación puede producir lesiones a nivel local o sistémico. Presentamos el caso clínico de una niña, que presentó inoculación de mercurio líquido en tejido subcutáneo tras la rotura de un termómetro de cristal, produciéndose daño a nivel local con esteatonecrosis del tejido. El diagnóstico se realizó mediante estudio radiológico y precisó intervención quirúrgica urgente con escisión en cuña de piel y tejido subcutáneo, guiada con radioscopia. Se descartó la extensión a nivel sistémico, comprobándose la normalidad de los niveles de mercurio en sangre y orina.Mercury thermometers are and have been, despite their manufacture being banned, one of the main sources of exposure at the paediatric age to elementary mercury (Hg in our environment. The toxicity produced by elementary Hg depends on the exposure channel and its length. Exposure through the digestive tract produces hardly any toxicity, but subcutaneous or intravenous inoculation and inhalation of mercury may produce damages at a local or system level. We present the case of a child who showed inoculation of liquid mercury in subcutaneous tissue after a liquid-in-glass thermometer broke. This provoked damages at a local level with steatonecrosis of the tissue. The diagnosis was decided through a radiological test and required urgent surgery with excision of skin and subcutaneous tissue, guided by radioscopy. Any spread at a system level was discarded. The levels of mercury in the bloodstream and in the urine were regular.

  2. On the Chalcogenophilicity of Mercury: Evidence for a Strong Hg–Se Bond in [TmBut]HgSePh and its Relevance to the Toxicity of Mercury

    Science.gov (United States)

    Melnick, Jonathan G.; Yurkerwich, Kevin

    2009-01-01

    One of the reasons for the toxic effects of mercury has been attributed to its influence on the biochemical roles of selenium. For this reason, it is important to understand details pertaining to the nature of Hg–Se interactions and this has been achieved by comparison of a series of mercury chalcogenolate complexes that are supported by tris(2-mercapto-1-t-butyl-imidazolyl)hydroborato ligation, namely [TmBut]HgEPh (E = S, Se, Te). In particular, X–ray diffraction studies on [TmBut]HgEPh demonstrate that although the Hg–S bonds involving the [TmBut] ligand are longer than the corresponding Cd–S bonds of [TmBut]CdEPh, the Hg–EPh bonds are actually shorter than the corresponding Cd–EPh bonds, an observation which indicates that the apparent covalent radii of the metals in these compounds are dependent on the nature of the bonds. Furthermore, the difference in Hg–EPh and Cd–EPh bond lengths is a function of the chalcogen and increases in the sequence S (0.010 Å) selenolate transfer from zinc to mercury upon treatment of [TmBut]HgSCH2C(O)N(H)Ph with [TmBut]ZnSePh. The significant selenophilicity of mercury is in accord with the aforementioned proposal that one reason for the toxicity of mercury is associated with it reducing the bioavailability of selenium. PMID:20020759

  3. Acute toxicity bioassay of mercury and silver on Capoeta fusca (black fish).

    Science.gov (United States)

    Mansouri, Borhan; Baramaki, Rahimeh; Ebrahimpour, Mohammad

    2012-06-01

    Since toxicity is based on the effect that a toxicant produces at a target site within an organism, establishing the relationship between the concentration of substance at the target site and the subsequent toxic effect can provide a tool for predicting toxicity. The behavior of a single toxicant could not be fully understood without the knowledge of the fact the physical and biochemical properties of substances that can change. To understand this, the acute toxicity of mercury (as HgSO₄) and silver (as AgSO₄) to Capoeta fusca (6 treatments in triplicate) was determined. During September 2009, C. fusca belonging to the family Cyprinidae, weighing 2.95 (±0.55) g, were obtained from qanats in Birjand, East of Iran. The fish were maintained in an aquarium system at a holding temperature of 21 (±0.2) and were allowed to adjust to lab conditions for 1 week before experimentation. The lethal concentration 50 (LC₅₀) values for HgSO₄ at 24, 48, 72, and 96 h of exposure were 0.32, 0.28, 0.26, and 0.24 mg L⁻¹, respectively. Also, the LC₅₀ values for AgSO₄ at 24, 48, 72, and 96 h of exposure were 0.014, 0.013, 0.013, and 0.013 mg L⁻¹, respectively. Results of this study showed that C. fusca was very sensitive to AgSO₄.

  4. Strategies for the engineered phytoremediation of toxic element pollution: mercury and arsenic.

    Science.gov (United States)

    Meagher, Richard B; Heaton, Andrew C P

    2005-12-01

    Plants have many natural properties that make them ideally suited to clean up polluted soil, water, and air, in a process called phytoremediation. We are in the early stages of testing genetic engineering-based phytoremediation strategies for elemental pollutants like mercury and arsenic using the model plant Arabidopsis. The long-term goal is to develop and test vigorous, field-adapted plant species that can prevent elemental pollutants from entering the food-chain by extracting them to aboveground tissues, where they can be managed. To achieve this goal for arsenic and mercury, and pave the way for the remediation of other challenging elemental pollutants like lead or radionucleides, research and development on native hyperaccumulators and engineered model plants needs to proceed in at least eight focus areas: (1) Plant tolerance to toxic elementals is essential if plant roots are to penetrate and extract pollutants efficiently from heterogeneous contaminated soils. Only the roots of mercury- and arsenic-tolerant plants efficiently contact substrates heavily contaminated with these elements. (2) Plants alter their rhizosphere by secreting various enzymes and small molecules, and by adjusting pH in order to enhance extraction of both essential nutrients and toxic elements. Acidification favors greater mobility and uptake of mercury and arsenic. (3) Short distance transport systems for nutrients in roots and root hairs requires numerous endogenous transporters. It is likely that root plasma membrane transporters for iron, copper, zinc, and phosphate take up ionic mercuric ions and arsenate. (4) The electrochemical state and chemical speciation of elemental pollutants can enhance their mobility from roots up to shoots. Initial data suggest that elemental and ionic mercury and the oxyanion arsenate will be the most mobile species of these two toxic elements. (5) The long-distance transport of nutrients requires efficient xylem loading in roots, movement through the

  5. Changing the dose metric for inhalation toxicity studies: short-term study in rats with engineered aerosolized amorphous silica nanoparticles.

    Science.gov (United States)

    Sayes, Christie M; Reed, Kenneth L; Glover, Kyle P; Swain, Keith A; Ostraat, Michele L; Donner, E Maria; Warheit, David B

    2010-03-01

    Inhalation toxicity and exposure assessment studies for nonfibrous particulates have traditionally been conducted using particle mass measurements as the preferred dose metric (i.e., mg or microg/m(3)). However, currently there is a debate regarding the appropriate dose metric for nanoparticle exposure assessment studies in the workplace. The objectives of this study were to characterize aerosol exposures and toxicity in rats of freshly generated amorphous silica (AS) nanoparticles using particle number dose metrics (3.7 x 10(7) or 1.8 x 10(8) particles/cm(3)) for 1- or 3-day exposures. In addition, the role of particle size (d(50) = 37 or 83 nm) on pulmonary toxicity and genotoxicity endpoints was assessed at several postexposure time points. A nanoparticle reactor capable of producing, de novo synthesized, aerosolized amorphous silica nanoparticles for inhalation toxicity studies was developed for this study. SiO(2) aerosol nanoparticle synthesis occurred via thermal decomposition of tetraethylorthosilicate (TEOS). The reactor was designed to produce aerosolized nanoparticles at two different particle size ranges, namely d(50) = approximately 30 nm and d(50) = approximately 80 nm; at particle concentrations ranging from 10(7) to 10(8) particles/cm(3). AS particle aerosol concentrations were consistently generated by the reactor. One- or 3-day aerosol exposures produced no significant pulmonary inflammatory, genotoxic, or adverse lung histopathological effects in rats exposed to very high particle numbers corresponding to a range of mass concentrations (1.8 or 86 mg/m(3)). Although the present study was a short-term effort, the methodology described herein can be utilized for longer-term inhalation toxicity studies in rats such as 28-day or 90-day studies. The expansion of the concept to subchronic studies is practical, due, in part, to the consistency of the nanoparticle generation method.

  6. Effects of chemical speciation in growth media on the toxicity of mercury(II).

    Science.gov (United States)

    Farrell, R E; Germida, J J; Huang, P M

    1993-05-01

    The toxicity of metals, including mercury, is expressed differently in different media, and the addition of soluble organics to the growth medium can have a significant impact on bioassay results. Although the effect of medium composition on metal toxicity is generally attributed to its effect on metal speciation (i.e., the chemical form in which the metal occurs), the importance of individual metal-ligand species remains largely unclear. Here, we report the results of a study that investigated, both experimentally and from a modeling perspective, the effects of complex soluble organic supplements on the acute toxicity (i.e., 50% inhibitory concentration [IC50]) of mercury to a Pseudomonas fluorescens isolate in chemically well-defined synthetic growth media (M-IIX). The media consisted of a basal inorganic salts medium supplemented with glycerol (0.1%, vol/vol) and a variety of common protein hydrolysates (0.1%, vol/vol), i.e., Difco beef extract (X = B), Casamino Acids (X = C), peptone (X = P), soytone (X = S), tryptone (X = T), and yeast extract (X = Y). These were analyzed to obtain cation, anion, and amino acid profiles and the results were used to compute the aqueous speciation of Hg(II) in the media. Respirometric bioassays were performed and IC50s were calculated. Medium components varied significantly in their effects on the acute toxicity of Hg(II) to the P. fluorescens isolate. IC50s ranged from 1.48 to 14.54 micrograms of Hg ml-1, and the acute toxicity of Hg(II) in the different media decreased in the order M-IIC > M-IIP > M-IIB > M-IIT > M-IIS > M-IIY.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Pulmonary Toxicity of a Formulated Preparation of Fenvalerate in Rats Subchronically Exposed by Nose Only Inhalation for 90 Days

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective The pulmonary toxicity of a commercially available formulated preparation of Fenvalerate (Fen), a synthetic pyrethroid has been studied in rats following subchronic nose only inhalation exposure route. Method  Adult male rats were exposed to Fen for 4h/day, 5 days a week for 90 days by using Flow Past Dynamic Nose only Inhalation Chamber. Results Fen exposed rats showed a significant increase in enzymatic activities of lactate dehydrogenase (LDH), acid phosphatase (ACP), alkaline phosphatase (ALP) and γ-glutamyl transferase (γ-GT) which are considered as biochemical indicators of pulmonary damage. The concomitant histopathological examination of Fen exposed rats' lung revealed inflammatory changes viz., influx of mononuclear cells admixed with a few giant cells in alveolar lumen, hypetrophied bronchiolar and alveolar epithelial lining cells and presence of edematous fluid in alveolar lumen alongwith congested parenchymatous blood vessels. Conclusion These results for the first time indicate the pulmonary toxic effects of a commonly used formulated Fen preparation by using rat model and nose only inhalation as the route of exposure.

  8. Carbon capture and sequestration: an exploratory inhalation toxicity assessment of amine-trapping solvents and their degradation products.

    Science.gov (United States)

    McDonald, Jacob D; Kracko, Dean; Doyle-Eisele, Melanie; Garner, C Edwin; Wegerski, Chris; Senft, Al; Knipping, Eladio; Shaw, Stephanie; Rohr, Annette

    2014-09-16

    Carbon dioxide (CO2) absorption with aqueous amine solvents is a method of carbon capture and sequestration (CCS) from flue gases. One concern is the possible release of amine solvents and degradation products into the atmosphere, warranting evaluation of potential pulmonary effects from inhalation. The CCS amines monoethanolamine (MEA), methyldiethanolamine (MDEA), and piperazine (PIP) underwent oxidative and CO2-mediated degradation for 75 days. C57bl/6N mice were exposed for 7 days by inhalation of 25 ppm neat amine or equivalant concentration in the degraded mixture. The aqueous solutions were nebulized to create the inhalation atmospheres. Pulmonary response was measured by changes in inflammatory cells in bronchoalveolar lavage fluid and cytokine expression in lung tissue. Ames mutagenicity and CHO-K1 micronucleus assays were applied to assess genotoxicity. Chemical analysis of the test atmosphere and liquid revealed complex mixtures, including acids, aldehydes, and other compounds. Exposure to oxidatively degraded MEA increased (p < 0.05) total cells, neutrophils, and lymphocytes compared to control mice and caused inflammatory cytokine expression (statistical increase at p < 0.05). MEA and CO2-degraded MEA were the only atmospheres to show statistical (p < 0.05) increase in oxidative stress. CO2 degradation resulted in a different composition, less degradation, and lower observed toxicity (less magnitude and number of effects) with no genotoxicity. Overall, oxidative degradation of the amines studied resulted in enhanced toxicity (increased magnitude and number of effects) compared to the neat chemicals.

  9. Mercury poisoning in two 13-year-old twin sisters

    OpenAIRE

    Ezzat Khodashenas; Mohammadhassan Aelami; Mahdi Balali-Mood

    2015-01-01

    Mercury (Hg) is a toxic agent that evaporates in room temperature and its inhalation may cause poisoning. Due to the nonspecific symptoms, diagnosis is difficult in special circumstances with no initial history of Hg exposure. We report two such cases of Hg poisoning. The patients were two sisters, presenting with pain in extremities, itchy rashes, sweating, salivation, weakness, and mood changes. They have used a compound that contains mercury, for treatment of pedicullosis three months befo...

  10. Is mercury in Tibetan Medicine toxic? Clinical, neurocognitive and biochemical results of an initial cross-sectional study.

    Science.gov (United States)

    Sallon, Sarah; Dory, Yahav; Barghouthy, Yazeed; Tamdin, Tsewang; Sangmo, Rigzin; Tashi, Jamyang; Yangdon, Sonam; Yeshi, Tenzin; Sadutshang, Tsetan; Rotenberg, Michal; Cohen, Elinor; Harlavan, Yehudit; Sharabi, Galit; Bdolah-Abram, Tali

    2017-02-01

    Mercury an important therapeutic substance in Tibetan Medicine undergoes complex "detoxification" prior to inclusion in multi-ingredient formulas. In an initial cross-sectional study, patients taking Tibetan Medicine for various conditions were evaluated for mercury toxicity. Two groups were identified: Group 1, patients taking " Tsothel" the most important detoxified mercury preparation and Group 2, patients taking other mercury preparations or mercury free Tibetan Medicine. Atomic fluorescence spectrometry of Tibetan Medicine showed mercury consumption 130 µg/kg/day (Group 1) and 30 µg/kg/day (Group 2) ( P ≤ 0.001), levels above EPA (RfDs) suggested threshold (0.3 µg/kg /day) for oral chronic exposure. Mean duration of Tibetan Medicine treatment was 9 ± 17 months (range 3-116) (Group 1) and 5 ± 1.96 months (range 1-114) (Group 2) (NS) with cumulative days of mercury containing Tibetan Medicine, 764 days ± 1214 (range 135-7330) vs. 103 days ± 111 (range 0-426), respectively ( P ≤ 0.001). Comparison of treatment groups with healthy referents (Group 3) not taking Tibetan Medicine showed no significant differences in prevalence of 23 non-specific symptoms of mercury toxicity, abnormal neurological, cardiovascular and dental findings and no correlation with mercury exposure variables; consumption, cumulative treatment days, blood/ urine Hg. Liver and renal function tests in treatment groups were not significantly increased compared to referents, with mean urine Beta2 Microglobulin within the normal range and not significantly associated with Hg exposure variables after correcting for confounding variables. Neurocognitive testing showed no significant intergroup differences for Wechsler Memory Scale, Grooved Pegboard, Visual Retention, but Group1 scores were better for Mini-Mental, Brief Word Learning, Verbal Fluency after correcting for confounding variables. These results suggest mercury containing Tibetan Medicine does not

  11. (Toxic hepatitis and acute renal failure after inhalation of chloride solvents: report of one case (author's transl))

    Energy Technology Data Exchange (ETDEWEB)

    Teixido Planas, J.; Martinez-Castelao, A.; Romero Gonzalez, R.; Grino Boira, J.; Gonzalez Segura, C.; Caralps Riera, A.

    1981-06-25

    Due to a combination of ingested ethanol and inhaled trichloroethylene (Tri) a 28 year old man developed toxic hepatitis and acute oliguric renal failure, both of which had a favorable evolution. Tri has been described as a cause of hepatic disfunction and acute renal failure due to acute tubular necrosis, although some of the cases described are controversial, because Tri was either contaminated by other dissolvents or could not be proven pure, with the exception of one case. In many there was ethanol ingestion. The Tri inhaled by our patient was found to contain less than 1% of carbon tetrachloride (C-Tchl). This would suggest the C-Tchl to be responsible for the clinical picture although the combination Tri/ethanol cannot be discarded as the causal agent, due to the small amount of contaminant present.

  12. Mangiferin, a Dietary Xanthone Protects Against Mercury-Induced Toxicity in HepG2 Cells

    Science.gov (United States)

    Agarwala, Sobhika; Rao, B. Nageshwar; Mudholkar, Kaivalya; Bhuwania, Ridhirama; Rao, B. S. Satish

    2012-01-01

    Mercury is one of the noxious heavy metal environmental toxicants and is a cause of concern for human exposure. Mangiferin (MGN), a glucosylxanthone found in Mangifera indica, reported to have a wide range of pharmacological properties. The objective of this study was to evaluate the cytoprotective potential of MGN, against mercury chloride (HgCl2) induced toxicity in HepG2 cell line. The cytoprotective effect of MGN on HgCl2 induced toxicity was assessed by colony formation assay, while antiapoptotic effect by fluorescence microscopy, flow cytometric DNA analysis, and DNA fragmentation pattern assays. Further, the cytoprotective effect of MGN against HgCl2 toxicity was assessed by using biochemical parameters like reduced glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) by spectrophotometrically, mitochondrial membrane potential by flowcytometry and the changes in reactive oxygen species levels by DCFH-DA spectrofluoremetric analysis. A significant increase in the surviving fraction was observed with 50 µM of MGN administered two hours prior to various concentrations of HgCl2. Further, pretreatment of MGN significantly decreased the percentage of HgCl2 induced apoptotic cells. Similarly, the levels of ROS generated by the HgCl2 treatment were inhibited significantly (P < 0.01) by MGN. MGN also significantly (P < 0.01) inhibited the HgCl2 induced decrease in GSH, GST, SOD, and CAT levels at all the post incubation intervals. Our study demonstrated the cytoprotective potential of MGN, which may be attributed to quenching of the ROS generated in the cells due to oxidative stress induced by HgCl2, restoration of mitochondrial membrane potential and normalization of cellular antioxidant levels. PMID:20629087

  13. The potential importance of steroids in the treatment of autistic spectrum disorders and other disorders involving mercury toxicity.

    Science.gov (United States)

    Geier, Mark R; Geier, David A

    2005-01-01

    Autism is a neurodevelopmental disorder that according to the Centers for Disease Control and Prevention (CDC) affects 1 in 150 children in the United States. Autism is characterized by impairments in social relatedness and communication, repetitive behaviors, abnormal movements, and sensory dysfunction. Recently emerging evidence suggests that mercury, especially from childhood vaccines, appears to be a factor in the development of the autistic disorders, and that autistic children have higher than normal body-burdens of mercury. In considering mercury toxicity, it has previously been shown that testosterone significantly potentates mercury toxicity, whereas estrogen is protective. Examination of autistic children has shown that the severity of autistic disorders correlates with the amount of testosterone present in the amniotic fluid, and an examination of a case-series of autistic children has shown that some have plasma testosterone levels that were significantly elevated in comparison neurotypical control children. A review of some of the current biomedical therapies for autistics, such as glutathione and cysteine, chelation, secretin, and growth hormone, suggests that they may in fact lower testosterone levels. We put forward the medical hypothesis that autistic disorders, in fact, represents a form of testosterone mercury toxicity, and based upon this observation, one can design novel treatments for autistics directed towards higher testosterone levels in autistic children. We suggest a series of experiments that need to be conducted in order to evaluate the exact mechanisms for mercury-testosterone toxicity, and various types of clinical manipulations that may be employed to control testosterone levels. It is hoped by devising therapies that address the steroid hormone pathways, in addition to the current treatments that successful lower heavy metal body-burdens of mercury, will work synergistically to improve clinical outcomes. In light of the fact that

  14. Mercury and selenium in European catfish (Silurus glanis) from Northern Italian Rivers: can molar ratio be a predictive factor for mercury toxicity in a top predator?

    Science.gov (United States)

    Squadrone, S; Benedetto, A; Brizio, P; Prearo, M; Abete, M C

    2015-01-01

    The study of mercury and selenium bioaccumulation in fish is crucially important for evaluating the extent of contamination in freshwater environments, and the possible health risk posed for humans when the antagonistic interactions of these two elements are considered. Several factors affect the risk of mercury intake from fish consumption, including mercury levels, human consumption patterns, and sensitive populations (e.g., pregnant women, foetuses, young children and unknown genetic factors). The protective effects of selenium on mercury toxicity have been extensively publicised in recent years, particularly targeting fish consumers. In this study, mercury (Hg) and selenium (Se) concentrations were determined in the muscle of European catfish (Silurus glanis) collected from North Italian Rivers. Differences in mercury and selenium levels, as a function of size, gender and location were investigated. Hg was strongly related to length, gender and location, while Se levels are not dependent on fish size or location. The mean Se/Hg molar ratio was strongly affected by location, and significantly related to length and age. Selenium was in molar excess of mercury in all sites, with a rank order of mean Se/Hg molar ratio of the Parma River (2.55)>Po River (1.71)>Tanaro River (1.66)>Bormida River (1.36). However, in 37% of analyzed samples, Hg exceeded the maximum level set by 1881/2006/EC and 629/2008/EC in fish muscle. The molar ratio of Se/Hg was 0.5mg/kg), and therefore the mean molar ratio cannot be considered as a safety criterion in top predator fish.

  15. Mercury

    CERN Document Server

    Balogh, André; Steiger, Rudolf

    2008-01-01

    Mercury, the planet closest to the Sun, is different in several respects from the other three terrestrial planets. In appearance, it resembles the heavily cratered surface of the Moon, but its density is high, it has a magnetic field and magnetosphere, but no atmosphere or ionosphere. This book reviews the progress made in Mercury studies since the flybys by Mariner 10 in 1974-75, based on the continued research using the Mariner 10 archive, on observations from Earth, and on increasingly realistic models of its interior evolution.

  16. Mercury

    CERN Document Server

    Mahoney, T J

    2014-01-01

    This gazetteer and atlas on Mercury lists, defines and illustrates every named (as opposed to merely catalogued) object and term as related to Mercury within a single reference work. It contains a glossary of terminology used, an index of all the headwords in the gazetteer, an atlas comprising maps and images with coordinate grids and labels identifying features listed in the gazetteer, and appendix material on the IAU nomenclature system and the transcription systems used for non-roman alphabets. This book is useful for the general reader, writers and editors dealing with astronomical themes, and those astronomers concerned with any aspect of astronomical nomenclature.

  17. Public Health and Economic Consequences of Methyl Mercury Toxicity to the Developing Brain

    National Research Council Canada - National Science Library

    Leonardo Trasande; Philip J. Landrigan; Clyde Schechter

    2005-01-01

    Methyl mercury is a developmental neurotoxicant. Exposure results principally from consumption by pregnant women of seafood contaminated by mercury from anthropogenic (70%) and natural (30%) sources...

  18. A chronic inhalation toxicity/oncogenicity study of methylethylketoxime in rats and mice.

    Science.gov (United States)

    Newton, P E; Wooding, W L; Bolte, H F; Derelanko, M J; Hardisty, J F; Rinehart, W E

    2001-12-01

    To evaluate the oncogenic potential of methylethylketoxime (MEKO), CD-1 mice (50/sex/group) and F-344 rats (50/sex/group) were coexposed 6 h/day, 5 days/wk for 18 mo (mice) or 26 mo (rats) via whole-body inhalation exposures to target vapor concentrations of 0, 15, 75, and 375 ppm (actual concentrations of 0, 15 +/- 1, 75 +/- 2, or 374 +/- 10 ppm). Satellite groups of rats and mice (10/sex/group/interval) were exposed for 12 mo (mice) and 3, 12, or 18 mo (rats) to evaluate chronic toxicity. Methyl ethyl ketone (MEK), a possible hydrolysis product of MEKO, was present at less than 1%. Treatment-related effects included increased body weight (male rats only), methemoglobin formation, hematology and clinical chemistry changes, increased liver weight, and increased spleen and testes weights (rats only). A high incidence of cataracts and corneal dystrophy occurred in both control and MEKO-exposed rats, with an earlier appearance and slightly higher incidence for these ocular lesions in MEKO-exposed animals compared to controls. Degenerative and reparative changes of the olfactory epithelium in the nasal turbinates, primarily limited to the dorsal meatus, occurred in both rats (75 and 374 ppm) and mice (15, 75, and 374 ppm). In addition, in the mice, liver changes included increased incidences of pigment in reticuloendothelial cells, centilobular hypertrophy, granulomatous inflammation, and a slightly increased incidence of necrosis (75 and 374 ppm). An increase in hepatocellular carcinomas occurred in male mice at 374 ppm. Additional MEKO-related findings in the rat included congestion of the spleen with pigment in reticuloendothelial cells and extramedullary hematopoiesis and a decreased incidence of lymphoreticular mononuclear cell leukemia. Effects observed in the liver of the rats included decreases in the incidence of both peribiliary fibrosis and hyperplasia/proliferation of the biliary duct, an increase of spongiosis hepatis in males, and an increase in the

  19. Mercury sensing and toxicity studies of novel latex fabricated silver nanoparticles.

    Science.gov (United States)

    Borase, Hemant P; Patil, Chandrashekhar D; Salunkhe, Rahul B; Suryawanshi, Rahul K; Salunke, Bipinchandra K; Patil, Satish V

    2014-11-01

    Safe and eco-friendly alternatives to currently used hazardous chemico-physical methods of silver nanoparticles (AgNPs) synthesis are need of time. Rapid, low cost, selective detection of toxic metals in environmental sample is important to take safety action. Toxicity assessment of engineered AgNPs is essential to avoid its side effects on human and non-target organisms. In the present study, biologically active latex from Euphorbia heterophylla (Poinsettia) was utilized for synthesis of AgNPs. AgNPs was of spherical shape and narrow size range (20-50 nm). Occurrence of elemental silver and crystalline nature of AgNPs was analyzed. Role of latex metabolites in reduction and stabilization of AgNPs was analyzed by FT-IR, protein coagulation test and phytochemical analysis. Latex-synthesized AgNPs showed potential in selective and sensitive detection of toxic mercury ions (Hg(2+)) with limit of detection around 100 ppb. Addition of Hg(2+) showed marked deviation in color and surface plasmon resonance spectra of AgNPs. Toxicity studies on aquatic non-target species Daphnia magna showed that latex-synthesized AgNPs (20.66 ± 1.52% immobilization) were comparatively very less toxic than chemically synthesized AgNPs (51.66 ± 1.52% immobilization). Similarly, comparative toxicity study on human red blood cells showed lower hemolysis (4.46 ± 0.01%) by latex-synthesized AgNPs as compared to chemically synthesized AgNPs causing 6.14 ± 0.01% hemolysis.

  20. The Effect of Mercury Vapor and the Role of Green Tea Extract on Brain Cells

    Directory of Open Access Journals (Sweden)

    Dhona Afriza

    2013-09-01

    Full Text Available Mercury is a wellknown toxic metal that is capable to induce free radical-induced oxidative stress. It can cause human disease including brain disorders. Objective: To identify the effect of mercury vapor inhalation on brain cells and the role of green tea extract (Camellia sinensis as antioxidant on the brain cells exposed to mercury. Methods: Fourty-eight male Mus musculus were divided into 8 groups, which were given treatment for 3 and 6 weeks. Group A did not receive any treatment and served as a negative control. Group B was a positive control exposed to Mercury. Group C was exposed to Mercury and treated with 26μg/g green tea extract. Group D was exposed to mercury and treated with 52μg/g green tea extract. All animals in the Group B, C, D were exposed to mercury through inhalation for 4 hours daily. The effect of mercury on the brain cells were examined histopathologically. Results: The numbers of necrotic cells counted in the green tea-treated mice group were significantly lower than those untreated group (p<0,05. Conclusion: Mercury vapor inhalation may cause necrosis on brain cells. Administration of green tea extract as an antioxidant reduced the amount of mercury-induced necrotic brain cells in mice.DOI: 10.14693/jdi.v20i2.151

  1. ACUTE TOXICITY OF MERCURY TO EMBRYOS OF Helisoma trivolvis (SAY, 1817 (MOLLUSCA: PLANORBIDAE

    Directory of Open Access Journals (Sweden)

    Passuni, G.

    2008-01-01

    Full Text Available Mercury is a metal very employed at industry and mining in Peru. The aim of current research was to determine embryotoxic lethal acute toxicity of Hg2+, in form of chloride of mercury (HgCl on 2 Helisoma trivolvis (Say, 1817 at 24 h exposure. Concentrations assayed were 514, 51.4, 5.14 and 0.51 ug Hg2+ L-1, since salt on base of HgCl using dechlorined water as diluents. Snail embryos 2 were considered dead when none rotation movement during since 30 seconds. Percentage of mortality of embryonic stages of H. trivolvis increased with each of concentrations crescents of Hg2+ at 24 h exposure. At a concentration of 514.4 ug Hg2+ L-1 was observed significantly differences in relation to control. Moreover, concentration of 514.4 ug Hg2+ L-1 showed differences with relation to other three treatments. LC was 2.49 ug Hg2+ L-1. Embryos of H. trivolvis were 50 higher sensible to Hg2+ in comparison to other freshwater snail species was concluded.

  2. Pulmonary toxicity of nanomaterials: a critical comparison of published in vitro assays and in vivo inhalation or instillation studies.

    Science.gov (United States)

    Landsiedel, Robert; Sauer, Ursula G; Ma-Hock, Lan; Schnekenburger, Jürgen; Wiemann, Martin

    2014-11-01

    To date, guidance on how to incorporate in vitro assays into integrated approaches for testing and assessment of nanomaterials is unavailable. In addressing this shortage, this review compares data from in vitro studies to results from in vivo inhalation or intratracheal instillation studies. Globular nanomaterials (ion-shedding silver and zinc oxide, poorly soluble titanium dioxide and cerium dioxide, and partly soluble amorphous silicon dioxide) and nanomaterials with higher aspect ratios (multiwalled carbon nanotubes) were assessed focusing on the Organisation for Economic Co-Operation and Development (OECD) reference nanomaterials for these substances. If in vitro assays are performed with dosages that reflect effective in vivo dosages, the mechanisms of nanomaterial toxicity can be assessed. In early tiers of integrated approaches for testing and assessment, knowledge on mechanisms of toxicity serves to group nanomaterials thereby reducing the need for animal testing.

  3. Mercury toxicity to terrestrial snails in a partial life cycle experiment.

    Science.gov (United States)

    Gimbert, Frédéric; Perrier, Fanny; Caire, Ange-Lyne; de Vaufleury, Annette

    2016-02-01

    Despite growing concerns about the potential adverse effects of elevated mercury (Hg) concentrations in the terrestrial environment, only a few toxicity data are available for soil invertebrates. The chronic toxicity of inorganic Hg-Hg(II)--through food or soil contaminations was therefore assessed for the snail Cantareus aspersus, a well-recognized soil quality bioindicator. The 28-day EC50s (the concentrations causing 50% effect) for the snail growth were 600 and 5048 mg Hg kg(-1) for food and soil, respectively. A survey of growth over its entire duration (91 days) allowed to show that the effects took place rapidly after the beginning of exposure and persisted in the long term. Reproduction was also impaired, and we established 28-day EC50s for sexual maturation and fecundity of 831 and 339 mg Hg kg(-1), respectively, for food and 1719 and 53 mg Hg kg(-1), respectively, for soil. Total Hg analyses in snails exposed to contaminated matrices revealed important bioaccumulation capacities up to 2000 mg Hg kg(-1) viscera. Critical limits in internal Hg concentration of about 500 and 1000 mg Hg kg(-1) were determined as thresholds for the induction of growth toxicity through food and soil exposure, respectively. These different values underlined differences in the uptake and toxicological dynamics of Hg according to its bioavailability in the source of exposure.

  4. Additional histopathologic examination of the lungs from a 3-month inhalation toxicity study with multiwall carbon nanotubes in rats.

    Science.gov (United States)

    Treumann, Silke; Ma-Hock, Lan; Gröters, Sibylle; Landsiedel, Robert; van Ravenzwaay, Bennard

    2013-07-01

    For hazard assessment of multiwalled carbon nanotubes (MWCNTs), a 90-day inhalation toxicity study has been performed with Nanocyl NC 7000 in accordance with OECD 413 test guideline. MWCNTs produced no systemic toxicity. However, increased lung weights, multifocal granulomatous inflammation, diffuse histiocytic and neutrophilic infiltrates, and intra-alveolar lipoproteinosis were observed in lung and lung-associated lymph nodes at 0.5 and 2.5mg/m(3). Additional investigations of the lungs were performed, including special stains for examination of connective tissue, and electron microscopy was performed to determine the location of the MWCNTs. The alveolar walls revealed no increase of collagen fibers, whereas within the microgranulomas a slight increase of collagen fibers was observed. The pleura did not reveal any increase in collagen fibers. Only a slight increase in reticulin fibers in the alveolar walls in animals of the 0.5 and 2.5mg/m(3) concentration group was noted. In the 0.1mg/m(3) group, the only animal revealing minimal granulomas exhibited a minimal increase in collagen within the granuloma. No increase in reticulin was observed. Electron microscopy demonstrated entangled MWCNTs within alveolar macrophages. Occasionally electron dense particles/detritus were observed within membrane-bound vesicles (interpreted as phagosomes), which could represent degraded MWCNTs. If so, MWCNTs were degradable by alveolar macrophages and not persistent within the lung. Inhalation of MWCNTs caused granulomatous inflammation within the lung parenchyma but not the pleura in any of the concentration groups. Thus, there are some similarities to effects caused by inhaled asbestos, but the hallmark effects, namely pleural inflammation and/or fibrosis leading to mesotheliomas, are absent.

  5. Mercury contamination: occupational risk of the dental surgeon

    Directory of Open Access Journals (Sweden)

    Cristiane K. KAMETANI

    2009-12-01

    Full Text Available Introduction and objective: Mercury is a widely used material in dental practice. However, it is one of the most dangerous environmental and occupational pollutants. Thus, the aim of this study is to analyze several aspects of mercury contamination, based on a literature review, in order to demonstrate the risks related to mishandling of mercury. Literature review: Some recommendations are stated regarding the handling and application of mercury in the dental office environment, once aesthetic materials have been replacing a large number of amalgam restorations. This could lead to mercury vapor exposure, a chemical risk to the health that many dental professionals do not always consider. Conclusion: Mercury can produce local or systemic toxic effects on the organism through vapor inhalation during amalgam preparation or during its replacement.

  6. Chronic inhalation toxicity and carcinogenicity studies on β-chloroprene in rats and hamsters

    NARCIS (Netherlands)

    Trochimowicz, H.J.; Löser, E.; Feron, V.J.; Clary, J.J.; Valentine, R.

    1998-01-01

    Three groups of 100 Wistar rats and Syrian golden hamsters of each sex were exposed by inhalation to 0, 10, or 50 ppm (v/v) β-chloroprene for 6 h/day, 5 days a week for up to 24 and 18 too, respectively. To maintain the chemical integrity of this highly reactive material in the exposure chambers, β-

  7. Do selenium and glutathione inhibit the toxic effects of mercury in marine lamellibranchs?

    Science.gov (United States)

    Patel, B; Chandy, J P; Patel, S

    1988-10-15

    , except in P. viridis where it increased by 39%. The results show unequivocally that Se does not offer any protection against the toxic effects of mercury in marine lamellibranchs, whereas in many marine vertebrates it does. GSH, a thiol-rich tripeptide, on the other hand, completely nullifies the toxic effects of Hg, both in vivo and in vitro.

  8. Mercury toxicity in beluga whale lymphocytes: Limited effects of selenium protection

    Energy Technology Data Exchange (ETDEWEB)

    Frouin, H. [Fisheries and Oceans Canada, Institute of Ocean Sciences, 9860 West Saanich Rd, P.O. Box 6000, Sidney, BC, V8L 4B2 (Canada); Loseto, L.L.; Stern, G.A. [Fisheries and Oceans Canada, Freshwater Institute, 501 University Crescent, Winnipeg, MB, R3T 2N6 (Canada); Haulena, M. [Vancouver Aquarium, 845 Avison Way, Vancouver, BC, V6G 3E2 (Canada); Ross, P.S., E-mail: peter.s.ross@dfo-mpo.gc.ca [Fisheries and Oceans Canada, Institute of Ocean Sciences, 9860 West Saanich Rd, P.O. Box 6000, Sidney, BC, V8L 4B2 (Canada)

    2012-03-15

    Increasing emissions of anthropogenic mercury represents a growing concern to the health of high trophic level marine mammals. In its organic form, this metal bioaccumulates, and can be toxic to several physiological endpoints, including the immune system. In this study, we (1) evaluated the effects of inorganic mercury (mercuric chloride, HgCl{sub 2}) and organic mercury (methylmercuric chloride, MeHgCl) on the in vitro function of lymphocytes isolated from the peripheral blood of beluga whales (Delphinapterus leucas); (2) characterized the potential protective effects of sodium selenite (Na{sub 2}SeO{sub 3}) on cell proliferation of HgCl{sub 2} or MeHgCl-treated beluga whale lymphocytes; and (3) compared these dose-dependent effects to measurements of blood Hg in samples collected from traditionally harvested beluga whales in the western Canadian Arctic. Lymphocyte proliferative responses were reduced following exposure to 1 {mu}M of HgCl{sub 2} and 0.33 {mu}M of MeHgCl. Decreased intracellular thiol levels were observed at 10 {mu}M of HgCl{sub 2} and 0.33 {mu}M of MeHgCl. Metallothionein induction was noted at 0.33 {mu}M of MeHgCl. Concurrent exposure of Se provided a degree of protection against the highest concentrations of inorganic Hg (3.33 and 10 {mu}M) or organic Hg (10 {mu}M) for T-lymphocytes. This in vitro protection of Se against Hg toxicity to lymphocytes may contribute to the in vivo protection in beluga whales exposed to high Hg concentrations. Current Hg levels in free-ranging beluga whales from the Arctic fall into the range of exposures which elicited effects on lymphocytes in our study, highlighting the potential for effects on host resistance to disease. The implications of a changing Arctic climate on Hg fate in beluga food webs and the consequences for the health of beluga whales remain pressing research needs.

  9. Assessment of mercury chloride-induced toxicity and the relevance of P2X7 receptor activation in zebrafish larvae.

    Science.gov (United States)

    Cruz, Fernanda Fernandes; Leite, Carlos Eduardo; Pereira, Talita Carneiro Brandão; Bogo, Maurício Reis; Bonan, Carla Denise; Battastini, Ana Maria Oliveira; Campos, Maria Martha; Morrone, Fernanda Bueno

    2013-09-01

    Zebrafish (Danio rerio) has been adopted as a model for behavioral, immunological and toxicological studies. Mercury is a toxic heavy metal released into the environment. There is evidence indicating that heavy metals can modulate ionotropic receptors, including the purinergic receptor P2X7. Therefore, this study evaluated the in vivo effects of acute exposure to mercury chloride (HgCl2) in zebrafish larvae and to investigate the involvement of P2X7R in mercury-related toxicity. Larvae survival was evaluated for 24 h after exposure to HgCl2, ATP or A740003. The combination of ATP (1 mM) and HgCl2 (20 μg/L) decreased survival when compared to ATP 1 mM. The antagonist A740003 (300 and 500 nM) increased the survival time, and reversed the mortality caused by ATP and HgCl2 in association. Quantitative real time PCR showed a decrease of P2X7R expression in the larvae treated with HgCl2 (20 μg/L). Evaluating the oxidative stress our results showed decreased CAT (catalase) activity and increased MDA (malondialdehyde) levels. Of note, the combination of ATP with HgCl2 showed an additive effect. This study provides novel evidence on the possible mechanisms underlying the toxicity induced by mercury, indicating that it is able to modulate P2X7R in zebrafish larvae.

  10. Acute Inhalation Toxicity and Blood Absorption of 2,4-Dinitroanisole (DNAN) in Rats

    Science.gov (United States)

    2015-03-17

    by BAE Systems, Ordnance Systems, 4509 West Stone Drive, Kingsport, TN 37660. The certificate of analysis provided by the supplier indicated that the...promote melting for vapor/aerosol generation during the inhalation exposures. Oral dosing suspensions were mixed on a weight/volume basis in corn oil...The second group of six rats was administered a single oral dose in corn oil via gavage at calculated equivalent doses to those exposed via

  11. The design, construction, and operation of a whole-body inhalation chamber for use in avian toxicity studies.

    Science.gov (United States)

    Olsgard, Mandy L; Smits, Judit E G

    2008-01-01

    Environmental risk assessments are broadening to include evaluations of avian species exposed to gaseous and particulate materials (Mineau, 2002b; Irvine, 2004; Carmalt, 2005). Since the avian respiratory tract is fundamentally different from the respiratory tract of rodents, the effects of gaseous materials on birds cannot validly be extrapolated from data derived from rodent exposure studies (Briant & Driver, 1992; Brown et al., 1997). To address the lack of avian-specific lowest observable effect levels used to calculate reference concentrations for airborne pollutants, a system was designed to facilitate research on inhalation toxicology in small birds. Birds have long been used as early indicators of poor air quality (Brown et al., 1997), and various chambers have been designed for head only exposures of larger birds (Briant & Driver, 1992). Smaller birds with short tracheal lengths and hooked beaks however require less restrictive exposure apparatus, thus warranting the proposed design. The chamber described in this article was designed to accommodate a small falcon, the American kestrel, a species frequently used in toxicological risk assessments (Wiemeyer & Lincer, 1987a; Smits & Bortolotti, 2001; Bortolotti et al., 2003; Fisher et al., 2006). To accomplish this, a 41-L closed inhalation system capable of exposing 12 adult American kestrels was constructed primarily of galvanized steel, polyvinyl chloride, and copper tubing. Humidified air was passed over the birds and subsequently decontaminated by an activated carbon filter and released to a HEPA filtration system. The proposed inhalation chamber was successfully used in 2005 and 2006 to expose a total of 55 male American kestrels to benzene and toluene. Measurements of various biochemical endpoints associated with benzene and toluene toxicity allowed us to study the effects of airborne pollutants on small nondomesticated birds in a controlled laboratory setting.

  12. A case series of children with apparent mercury toxic encephalopathies manifesting with clinical symptoms of regressive autistic disorders.

    Science.gov (United States)

    Geier, David A; Geier, Mark R

    2007-05-15

    Impairments in social relatedness and communication, repetitive behaviors, and stereotypic abnormal movement patterns characterize autism spectrum disorders (ASDs). It is clear that while genetic factors are important to the pathogenesis of ASDs, mercury exposure can induce immune, sensory, neurological, motor, and behavioral dysfunctions similar to traits defining or associated with ASDs. The Institutional Review Board of the Institute for Chronic Illnesses (Office for Human Research Protections, U.S. Department of Health and Human Services, IRB number IRB00005375) approved the present study. A case series of nine patients who presented to the Genetic Centers of America for a genetic/developmental evaluation are discussed. Eight of nine patients (one patient was found to have an ASD due to Rett's syndrome) (a) had regressive ASDs; (b) had elevated levels of androgens; (c) excreted significant amounts of mercury post chelation challenge; (d) had biochemical evidence of decreased function in their glutathione pathways; (e) had no known significant mercury exposure except from Thimerosal-containing vaccines/Rho(D)-immune globulin preparations; and (f) had alternate causes for their regressive ASDs ruled out. There was a significant dose-response relationship between the severity of the regressive ASDs observed and the total mercury dose children received from Thimerosal-containing vaccines/Rho (D)-immune globulin preparations. Based upon differential diagnoses, 8 of 9 patients examined were exposed to significant mercury from Thimerosal-containing biologic/vaccine preparations during their fetal/infant developmental periods, and subsequently, between 12 and 24 mo of age, these previously normally developing children suffered mercury toxic encephalopathies that manifested with clinical symptoms consistent with regressive ASDs. Evidence for mercury intoxication should be considered in the differential diagnosis as contributing to some regressive ASDs.

  13. Signs and symptoms of mercury-exposed gold miners.

    Science.gov (United States)

    Bose-O'Reilly, Stephan; Bernaudat, Ludovic; Siebert, Uwe; Roider, Gabriele; Nowak, Dennis; Drasch, Gustav

    2017-03-30

    Gold miners use mercury to extract gold from ore adding liquid mercury to the milled gold-containing ore. This results in a mercury-gold compound, called amalgam. Miners smelt this amalgam to obtain gold, vaporizing it and finally inhaling the toxic mercury fumes. The objective was to merge and analyze data from different projects, to identify typical signs and symptoms of chronic inorganic mercury exposure. Miners and community members from various artisanal small-scale gold mining areas had been examined (Philippines, Mongolia, Tanzania, Zimbabwe, Indonesia). Data of several health assessments were pooled. Urine, blood and hair samples were analyzed for mercury (N = 1252). Questionnaires, standardized medical examinations and neuropsychological tests were used. Participants were grouped into: Controls (N = 209), living in an exposed area (N = 408), working with mercury as panners (N = 181), working with mercury as amalgam burners (N = 454). Chi2 test, linear trend test, Mann-Whitney test, Kruskal-Wallis test, correlation coefficient, Spearman's rho, and analysis of variance tests were used. An algorithm was used to define participants with chronic mercury intoxication. Mean mercury concentrations in all exposed subgroups were elevated and above threshold limits, with amalgam burners showing highest levels. Typical symptoms of chronic metallic mercury intoxication were tremor, ataxia, coordination problems, excessive salivation and metallic taste. Participants from the exposed groups showed poorer results in different neuropsychological tests in comparison to the control group. Fifty-four percent of the high-exposed group (amalgam burners) were diagnosed as being mercury-intoxicated, compared to 0% within the control group (Chi2 p mercury intoxication, with tremor, ataxia and other neurological symptoms together with a raised body burden of mercury was clinically diagnosed in exposed people in artisanal small-scale mining areas. The mercury exposure needs to be

  14. Exposure of cultured human proximal tubular cells to cadmium, mercury, zinc and bismuth: toxicity and metallothionein induction.

    Science.gov (United States)

    Rodilla, V; Miles, A T; Jenner, W; Hawksworth, G M

    1998-08-14

    The kidney, in particular the proximal convoluted tubule, is a major target site for the toxic effects of various metals. However, little is known about the early effects of these metals after acute exposure in man. In the present study we have evaluated the toxicity of several inorganic metal compounds (CdCl2, HgCl2, ZnCl2, and Bi(NO3)3) and the induction of metallothionein by these compounds in cultured human proximal tubular (HPT) cells for up to 4 days. The results showed that bismuth was not toxic even at the highest dose (100 microM) used, while zinc, cadmium and mercury exhibited varying degrees of toxicity, zinc being the least toxic and mercury the most potent. A significant degree of interindividual variation between the different isolates used in these experiments was also observed. All metals used in the present study induced MT, as revealed by immunocytochemistry. All metals showed maximal induction between 1 and 3 days after treatment. Although a certain amount of constitutive MT was present in the cultures, the intensity of the staining varied with time in culture and between the different isolates studied. No correlation could be made between the intensity of the staining in control cultures (indicating total amount of constitutive MT) and the susceptibility of a given isolate to metal toxicity. Furthermore, no correlation could be made between metal-induced MT and the susceptibility of a given isolate to that particular metal.

  15. Inhalation Toxicology. 11. The Effect of Elevated Temperature on Carbon Monoxide Toxicity

    Science.gov (United States)

    1990-12-01

    TEMPERATURE ON CARBON MONOXIDE TOXICITY INTRODUCTION The use of the laboratory rat as an animal model for determining the toxicity of combustion gases is...response of rats during exercise. J Appl Physiol. 1968; 24:747-50. 7. Hubbard RW, Matthew WT, Linduska JD, et al. The laboratory rat as a model for

  16. Occupational Metallic Mercury Poisoning in Gilders.

    Science.gov (United States)

    Vahabzadeh, M; Balali-Mood, M

    2016-04-01

    Occupational exposure to elemental mercury vapor usually occurs through inhalation during its utilizations. This leads to a variety of adverse health effects. In some Islamic cities, this type of poisoning may occur during gilding of shrines using elemental mercury with gold. Herein, we report on three male patients aged 20-53 years, who were diagnosed with occupational metallic mercury poisoning due to gilding of a shrine. All patients presented with neuro-psychiatric disorders such as anxiety, loss of memory and concentration, and sleep disorders with high urinary mercury concentrations of 326-760 μg/L upon referring, 3-10 days after cessation of elemental mercury exposure. Following chelating therapy, the patients recovered clinically and their mercury concentrations declined to non-toxic level (<25 μg/L). Health, environmental and labor authorities, as well as the gilders should be aware of the toxicity risk of exposure to metalic mercury during gilding in closed environments and act accordingly.

  17. Alternative acute inhalation toxicity testing by determination of the concentration-time-mortality relationship : experimental comparison with standard LC50 testing

    NARCIS (Netherlands)

    Zwart, A.; Arts, J.H.E.; Berge, W.F. ten; Appelman, L.M.

    1992-01-01

    A new design for acute inhalation toxicity testing was evaluated and compared with results obtained according to OECD guideline 403. The new design consists of a range-finding test, which is compatible with a conventional limit test, and can be followed by determination of a

  18. Acute Lethality of Inhaled Hydrogen Cyanide in the Laboratory Rat: Impact of Concentration x Time Profile and Evaluation of the Predictivity of Toxic Load Models

    Science.gov (United States)

    2013-05-03

    Naval Medical Research Unit Dayton Acute Lethality of Inhaled Hydrogen Cyanide in the Laboratory Rat : Impact of Concentration × Time Profile and...Cyanide in the Laboratory Rat : Impact of Concentration x Time Profile and Evaluation of the Predictivity of “Toxic Load” Models. 5a. Contract

  19. Inhalation toxicity of (1→3-β-D glucan: recent advances

    Directory of Open Access Journals (Sweden)

    Birgitta Fogelmark

    1997-01-01

    Full Text Available To investigate the effects of (1→3-β-D-glucan after inhalation, animals were exposed to different forms of glucan and the number of lung lavage cells was determined 24 h after exposure. None of the different forms assayed caused any increase in cell numbers. In animals exposed to endotoxin, all types of cells were increased after 24 h. A simultaneous exposure to curdlan reduced this increase in a dose-related fashion. The results suggest that (1→3-β-D-glucan-related acute injury to the lung is induced by mechanisms other than those induced by inflammagenic agents such as endotoxin.

  20. Airway irritation, inflammation, and toxicity in mice following inhalation of metal oxide nanoparticles

    DEFF Research Database (Denmark)

    Larsen, Søren T; Jackson, Petra; Poulsen, Steen S

    2016-01-01

    in the airways following inhalation. In the present study, the acute (24 h) and persistent (13 weeks) effects in the airways after a single exposure to metal oxide nanoparticles were studied using a murine inhalation model. Mice were exposed 60 min to aerosols of either ZnO, TiO2, Al2O3 or CeO2 and the deposited...... particles except TiO2. The ranking of potency regarding induction of acute lung inflammation was Al2O3 = TiO2 CeO2 ≪ ZnO. Exposure to CeO2 gave rise to a more persistent inflammation; both neutrophilic and lymphocytic inflammation was seen 13 weeks after exposure. As the only particles, ZnO caused......Metal oxide nanoparticles are used in a broad range of industrial processes and workers may be exposed to aerosols of the particles both during production and handling. Despite the widespread use of these particles, relatively few studies have been performed to investigate the toxicological effects...

  1. Glutamate‑mediated effects of caffeine and interferon‑γ on mercury-induced toxicity.

    Science.gov (United States)

    Engin, Ayse Basak; Engin, Evren Doruk; Golokhvast, Kirill; Spandidos, Demetrios A; Tsatsakis, Aristides M

    2017-05-01

    The molecular mechanisms mediating mercury‑induced neurotoxicity are not yet completely understood. Thus, the aim of this study was to investigate whether the severity of MeHg‑ and HgCl2‑mediated cytotoxicity to SH‑SY5Y human dopaminergic neurons can be attenuated by regulating glutamate‑mediated signal‑transmission through caffeine and interferon‑γ (IFN‑γ). The SH‑SY5Y cells were exposed to 1, 2 and 5 µM of either MeHgCl2 or HgCl2 in the presence or absence of L‑glutamine. To examine the effect of adenosine receptor antagonist, the cells were treated with 10 and 20 µM caffeine. The total mitochondrial metabolic activity and oxidative stress intensity coefficient were determined in the 1 ng/ml IFN‑γ‑ and glutamate‑stimulated SH‑SY5Y cells. Following exposure to mercury, the concentration‑dependent decrease in mitochondrial metabolic activity inversely correlated with oxidative stress intensity. MeHg was more toxic than HgCl2. Mercury‑induced neuronal death was dependent on glutamate‑mediated excitotoxicity. Caffeine reduced the mercury‑induced oxidative stress in glutamine-containing medium. IFN‑γ treatment decreased cell viability and increased oxidative stress in glutamine‑free medium, despite caffeine supplementation. Although caffeine exerted a protective effect against MeHg-induced toxicity with glutamate transmission, under co‑stimulation with glutamine and IFN‑γ, caffeine decreased the MeHg‑induced average oxidative stress only by half. Thereby, our data indicate that the IFN‑γ stimulation of mercury‑exposed dopaminergic neurons in neuroinflammatory diseases may diminish the neuroprotective effects of caffeine.

  2. Mercury toxicity in the shark (Squalus acanthias) rectal gland: apical CFTR chloride channels are inhibited by mercuric chloride.

    Science.gov (United States)

    Ratner, Martha A; Decker, Sarah E; Aller, Stephen G; Weber, Gerhard; Forrest, John N

    2006-03-01

    In the shark rectal gland, basolateral membrane proteins have been suggested as targets for mercury. To examine the membrane polarity of mercury toxicity, we performed experiments in three preparations: isolated perfused rectal glands, primary monolayer cultures of rectal gland epithelial cells, and Xenopus oocytes expressing the shark cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. In perfused rectal glands we observed: (1) a dose-dependent inhibition by mercury of forskolin/3-isobutyl-1-methylxanthine (IBMX)-stimulated chloride secretion; (2) inhibition was maximal when mercury was added before stimulation with forskolin/IBMX; (3) dithiothrietol (DTT) and glutathione (GSH) completely prevented inhibition of chloride secretion. Short-circuit current (Isc) measurements in monolayers of rectal gland epithelial cells were performed to examine the membrane polarity of this effect. Mercuric chloride inhibited Isc more potently when applied to the solution bathing the apical vs. the basolateral membrane (23 +/- 5% and 68 +/- 5% inhibition at 1 and 10 microM HgCl2 in the apical solution vs. 2 +/- 0.9% and 14 +/- 5% in the basolateral solution). This inhibition was prevented by pre-treatment with apical DTT or GSH; however, only the permeant reducing agent DTT reversed mercury inhibition when added after exposure. When the shark rectal gland CFTR channel was expressed in Xenopus oocytes and chloride conductance was measured by two-electrode voltage clamping, we found that 1 microM HgCl2 inhibited forskolin/IBMX conductance by 69.2 +/- 2.0%. We conclude that in the shark rectal gland, mercury inhibits chloride secretion by interacting with the apical membrane and that CFTR is the likely site of this action.

  3. Ethylene Oxide: Acute Four-Hour and One-Hour Inhalation Toxicity Testing in Rats

    Directory of Open Access Journals (Sweden)

    William M. Snellings

    2011-01-01

    Full Text Available Ethylene oxide was tested on groups of rats for either 4-hour or 1-hour inhalation exposure, followed by 14 days of observation. Groups of five Sprague-Dawley rats/sex were exposed, and clinical signs and mortality were recorded. Clinical signs noted included irregular breathing, absence of certain reflexes, and tremors. Rats that died had moderate to severe pulmonary congestion. The calculated LC50 values, reported as ppm by volume (with 95% confidence limits, were as follows. 4-hour LC50 values were 1972 (1887 to 2061 ppm for males; 1537 (1391 to 1698 ppm for females; 1741 (1655 to 1831 ppm for the combined sexes. The 1-hour LC50 values were 5748 (5276 to 6262 ppm for males; 4439 (4034 to 4884 ppm for females; 5029 (4634 to 5459 ppm for the combined sexes.

  4. Grizzly bear hair reveals toxic exposure to mercury through salmon consumption.

    Science.gov (United States)

    Noël, Marie; Spence, Jody; Harris, Kate A; Robbins, Charles T; Fortin, Jennifer K; Ross, Peter S; Christensen, Jennie R

    2014-07-01

    Mercury obtained from the diet accumulates in mammalian hair as it grows thus preserving a record of mercury intake over the growth period of a given hair segment. We adapted a microanalysis approach, using laser ablation inductively coupled plasma mass spectrometry, to characterize temporal changes in mercury exposure and uptake in wild and captive grizzly bears. Captive grizzlies fed diets containing known and varied amounts of mercury provided data to allow prediction of Hg ingestion rates in wild bears. Here, we show, for the first time, that 70% of the coastal grizzly bears sampled had Hg levels exceeding the neurochemical effect level proposed for polar bears. In a context where the international community is taking global actions to reduce Hg emissions through the "Minamata Convention on Mercury", our study provides valuable information on the exposure to mercury of these grizzly bears already under many threats.

  5. Inhalation method for delivery of nanoparticles to the Drosophila respiratory system for toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Posgai, Ryan; Ahamed, Maqusood [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States); Hussain, Saber M. [Applied Biotechnology Branch, Human Effectiveness Directorate Air Force Research Laboratory/RHBP, Wright-Patterson Air Force Base, OH, 45433 (United States); Rowe, John J. [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States); Nielsen, Mark G., E-mail: Mark.Nielsen@notes.udayton.edu [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States)

    2009-12-20

    The growth of the nanotechnology industry and subsequent proliferation of nanoparticle types present the need to rapidly assess nanoparticle toxicity. We present a novel, simple and cost-effective nebulizer-based method to deliver nanoparticles to the Drosophila melanogaster respiratory system, for the purpose of toxicity testing. FluoSpheres (registered) , silver, and CdSe/ZnS nanoparticles of different sizes were effectively aerosolized, showing the system is capable of functioning with a wide range of nanoparticle types and sizes. Red fluorescent CdSe/ZnS nanoparticles were successfully delivered to the fly respiratory system, as visualized by fluorescent microscopy. Silver coated and uncoated nanoparticles were delivered in a toxicity test, and induced Hsp70 expression in flies, confirming the utility of this model in toxicity testing. This is the first method developed capable of such delivery, provides the advantage of the Drosophila health model, and can serve as a link between tissue culture and more expensive mammalian models in a tiered toxicity testing strategy.

  6. Acute toxicity when concentration varies with time: A case study with carbon monoxide inhalation by rats.

    Science.gov (United States)

    Sweeney, Lisa M; Sommerville, Douglas R; Goodwin, Michelle R; James, R Arden; Channel, Stephen R

    2016-10-01

    Exposure to time-varying concentrations of toxic compounds is the norm in both occupational settings and daily human life, but little has been done to investigate the impact of variations in concentration on toxic outcomes; this case study with carbon monoxide helps fill that gap. Median acute lethality of 10-, 20-, 40-, and 60-min continuous exposures of rats to carbon monoxide was well described by the toxic load model (k = C(n) × t; k is constant, C = test concentration, n = toxic load exponent, and t = exposure duration) with n = 1.74. Dose response-relationships for 1-h exposures including a recovery period between 10- or 20-min pulses showed greater similarity (in both median lethality and steepness of dose-response curve) to continuous exposures with equivalent pulse duration and concentration, rather than a 60-min exposure with equivalent time-weighted average concentrations or toxic load. When pulses were of unequal concentration (3:1 ratio), only the high concentration pulse contributed to lethality. These findings show that fluctuations or interruptions in exposure over a short time scale (60 min or less) can have a substantial impact on outcomes (when n > 1), and thus high-resolution monitoring data are needed to aid interpretation of resulting outcomes.

  7. Bioaccessibility, bioavailability and toxicity of commercially relevant iron- and chromium-based particles: in vitro studies with an inhalation perspective

    Directory of Open Access Journals (Sweden)

    Hedberg Yolanda

    2010-09-01

    Full Text Available Abstract Background Production of ferrochromium alloys (FeCr, master alloys for stainless steel manufacture, involves casting and crushing processes where particles inevitably become airborne and potentially inhaled. The aim of this study was to assess potential health hazards induced by inhalation of different well-characterized iron- and chromium-based particles, i.e. ferrochromium (FeCr, ferrosiliconchromium (FeSiCr, stainless steel (316L, iron (Fe, chromium (Cr, and chromium(IIIoxide (Cr2O3, in different size fractions using in vitro methods. This was done by assessing the extent and speciation of released metals in synthetic biological medium and by analyzing particle reactivity and toxicity towards cultured human lung cells (A549. Results The amount of released metals normalized to the particle surface area increased with decreasing particle size for all alloy particles, whereas the opposite situation was valid for particles of the pure metals. These effects were evident in artificial lysosomal fluid (ALF of pH 4.5 containing complexing agents, but not in neutral or weakly alkaline biological media. Chromium, iron and nickel were released to very low extent from all alloy particles, and from particles of Cr due to the presence of a Cr(III-rich protective surface oxide. Released elements were neither proportional to the bulk nor to the surface composition after the investigated 168 hours of exposure. Due to a surface oxide with less protective properties, significantly more iron was released from pure iron particles compared with the alloys. Cr was predominantly released as Cr(III from all particles investigated and was strongly complexed by organic species of ALF. Cr2O3 particles showed hemolytic activity, but none of the alloy particles did. Fine-sized particles of stainless steel caused however DNA damage, measured with the comet assay after 4 h exposure. None of the particles revealed any significant cytotoxicity in terms of cell death

  8. Acute mercury poisoning among children in two provinces of Turkey.

    Science.gov (United States)

    Carman, Kursat Bora; Tutkun, Engin; Yilmaz, Hinc; Dilber, Cengiz; Dalkiran, Tahir; Cakir, Baris; Arslantas, Didem; Cesaretli, Yildirim; Aykanat, Selin Aktaş

    2013-06-01

    Elemental mercury exposure occurs frequently and is potentially a toxic, particularly in children. Children are often attracted to elemental mercury because of its color, density, and tendency to form beads. Clinical manifestations of elemental mercury intoxication vary depending on its form, concentration, route of ingestion, and the duration of exposure. We present data on 179 pediatric cases of elemental mercury poisoning from exposure to mercury in schools in two different provinces of Turkey. Of all patients, 160 children had both touched/played with the mercury and inhaled its vapors, while 26 children had only inhaled the mercury vapor, two children reported having tasted the mercury. The median duration of exposure was 5 min (min 1-max 100), and 11 (6 %) children were exposed to the mercury for more than 24 h at home. More than half of the children (51.9 %) were asymptomatic at admission. Headache was the most common presenting complaint. The results of physical and neurological examinations were normal in 80 (44.6 %) children. Mid-dilated/dilated pupils were the most common neurological abnormality, and this sign was present in 90 (50.2 %) children. Mercury levels were measured in 24-h urine samples daily, and it was shown that the median urinary level of mercury was 29.80 μg/L (min, 2.40 μg/L; max, 4,687 μg/L). A positive correlation was also found between the duration of exposure and urinary mercury levels (r = 0.23, p = 0.001). All patients were followed up for 6 months. On the first follow-up visit performed 1 month after discharge, the neurological examinations of all patients were normal except for those patients with peripheral neuropathy and visual field defects. On the last follow-up visit at the sixth month, only two children still experienced visual field defects. In conclusion, this study is one of the largest case series of mercury intoxication of students in schools. Elemental mercury exposure can be potentially toxic, and its

  9. Medical countermeasure against respiratory toxicity and acute lung injury following inhalation exposure to chemical warfare nerve agent VX.

    Science.gov (United States)

    Nambiar, Madhusoodana P; Gordon, Richard K; Rezk, Peter E; Katos, Alexander M; Wajda, Nikolai A; Moran, Theodore S; Steele, Keith E; Doctor, Bhupendra P; Sciuto, Alfred M

    2007-03-01

    To develop therapeutics against lung injury and respiratory toxicity following nerve agent VX exposure, we evaluated the protective efficacy of a number of potential pulmonary therapeutics. Guinea pigs were exposed to 27.03 mg/m(3) of VX or saline using a microinstillation inhalation exposure technique for 4 min and then the toxicity was assessed. Exposure to this dose of VX resulted in a 24-h survival rate of 52%. There was a significant increase in bronchoalveolar lavage (BAL) protein, total cell number, and cell death. Surprisingly, direct pulmonary treatment with surfactant, liquivent, N-acetylcysteine, dexamethasone, or anti-sense syk oligonucleotides 2 min post-exposure did not significantly increase the survival rate of VX-exposed guinea pigs. Further blocking the nostrils, airway, and bronchioles, VX-induced viscous mucous secretions were exacerbated by these aerosolized treatments. To overcome these events, we developed a strategy to protect the animals by treatment with atropine. Atropine inhibits muscarinic stimulation and markedly reduces the copious airway secretion following nerve agent exposure. Indeed, post-exposure treatment with atropine methyl bromide, which does not cross the blood-brain barrier, resulted in 100% survival of VX-exposed animals. Bronchoalveolar lavage from VX-exposed and atropine-treated animals exhibited lower protein levels, cell number, and cell death compared to VX-exposed controls, indicating less lung injury. When pulmonary therapeutics were combined with atropine, significant protection to VX-exposure was observed. These results indicate that combinations of pulmonary therapeutics with atropine or drugs that inhibit mucous secretion are important for the treatment of respiratory toxicity and lung injury following VX exposure.

  10. Toxic Effects of Mercury on the Cardiovascular and Central Nervous Systems

    Directory of Open Access Journals (Sweden)

    Bruna Fernandes Azevedo

    2012-01-01

    Full Text Available Environmental contamination has exposed humans to various metal agents, including mercury. This exposure is more common than expected, and the health consequences of such exposure remain unclear. For many years, mercury was used in a wide variety of human activities, and now, exposure to this metal from both natural and artificial sources is significantly increasing. Many studies show that high exposure to mercury induces changes in the central nervous system, potentially resulting in irritability, fatigue, behavioral changes, tremors, headaches, hearing and cognitive loss, dysarthria, incoordination, hallucinations, and death. In the cardiovascular system, mercury induces hypertension in humans and animals that has wide-ranging consequences, including alterations in endothelial function. The results described in this paper indicate that mercury exposure, even at low doses, affects endothelial and cardiovascular function. As a result, the reference values defining the limits for the absence of danger should be reduced.

  11. Toxic Effects of Mercury on the Cardiovascular and Central Nervous Systems

    Science.gov (United States)

    Fernandes Azevedo, Bruna; Barros Furieri, Lorena; Peçanha, Franck Maciel; Wiggers, Giulia Alessandra; Frizera Vassallo, Paula; Ronacher Simões, Maylla; Fiorim, Jonaina; Rossi de Batista, Priscila; Fioresi, Mirian; Rossoni, Luciana; Stefanon, Ivanita; Alonso, María Jesus; Salaices, Mercedes; Valentim Vassallo, Dalton

    2012-01-01

    Environmental contamination has exposed humans to various metal agents, including mercury. This exposure is more common than expected, and the health consequences of such exposure remain unclear. For many years, mercury was used in a wide variety of human activities, and now, exposure to this metal from both natural and artificial sources is significantly increasing. Many studies show that high exposure to mercury induces changes in the central nervous system, potentially resulting in irritability, fatigue, behavioral changes, tremors, headaches, hearing and cognitive loss, dysarthria, incoordination, hallucinations, and death. In the cardiovascular system, mercury induces hypertension in humans and animals that has wide-ranging consequences, including alterations in endothelial function. The results described in this paper indicate that mercury exposure, even at low doses, affects endothelial and cardiovascular function. As a result, the reference values defining the limits for the absence of danger should be reduced. PMID:22811600

  12. Six-month low level chlorine dioxide gas inhalation toxicity study with two-week recovery period in rats

    Science.gov (United States)

    2012-01-01

    Background Chlorine dioxide (CD) gas has a potent antimicrobial activity at extremely low concentration and may serve as a new tool for infection control occupationally as well as publicly. However, it remains unknown whether the chronic exposure of CD gas concentration effective against microbes is safe. Therefore, long-term, low concentration CD gas inhalation toxicity was studied in rats as a six-month continuous whole-body exposure followed by a two-week recovery period, so as to prove that the CD gas exposed up to 0.1 ppm (volume ratio) is judged as safe on the basis of a battery of toxicological examinations. Methods CD gas at 0.05 ppm or 0.1 ppm for 24 hours/day and 7 days/week was exposed to rats for 6 months under an unrestrained condition with free access to chow and water in a chamber so as to simulate the ordinary lifestyle in human. The control animals were exposed to air only. During the study period, the body weight as well as the food and water consumptions were recorded. After the 6-month exposure and the 2-week recovery period, animals were sacrificed and a battery of toxicological examinations, including biochemistry, hematology, necropsy, organ weights and histopathology, were performed. Results Well regulated levels of CD gas were exposed throughout the chamber over the entire study period. No CD gas-related toxicity sign was observed during the whole study period. No significant difference was observed in body weight gain, food and water consumptions, and relative organ weight. In biochemistry and hematology examinations, changes did not appear to be related to CD gas toxicity. In necropsy and histopathology, no CD gas-related toxicity was observed even in expected target respiratory organs. Conclusions CD gas up to 0.1 ppm, exceeding the level effective against microbes, exposed to whole body in rats continuously for six months was not toxic, under a condition simulating the conventional lifestyle in human. PMID:22348507

  13. Six-month low level chlorine dioxide gas inhalation toxicity study with two-week recovery period in rats

    Directory of Open Access Journals (Sweden)

    Akamatsu Akinori

    2012-02-01

    Full Text Available Abstract Background Chlorine dioxide (CD gas has a potent antimicrobial activity at extremely low concentration and may serve as a new tool for infection control occupationally as well as publicly. However, it remains unknown whether the chronic exposure of CD gas concentration effective against microbes is safe. Therefore, long-term, low concentration CD gas inhalation toxicity was studied in rats as a six-month continuous whole-body exposure followed by a two-week recovery period, so as to prove that the CD gas exposed up to 0.1 ppm (volume ratio is judged as safe on the basis of a battery of toxicological examinations. Methods CD gas at 0.05 ppm or 0.1 ppm for 24 hours/day and 7 days/week was exposed to rats for 6 months under an unrestrained condition with free access to chow and water in a chamber so as to simulate the ordinary lifestyle in human. The control animals were exposed to air only. During the study period, the body weight as well as the food and water consumptions were recorded. After the 6-month exposure and the 2-week recovery period, animals were sacrificed and a battery of toxicological examinations, including biochemistry, hematology, necropsy, organ weights and histopathology, were performed. Results Well regulated levels of CD gas were exposed throughout the chamber over the entire study period. No CD gas-related toxicity sign was observed during the whole study period. No significant difference was observed in body weight gain, food and water consumptions, and relative organ weight. In biochemistry and hematology examinations, changes did not appear to be related to CD gas toxicity. In necropsy and histopathology, no CD gas-related toxicity was observed even in expected target respiratory organs. Conclusions CD gas up to 0.1 ppm, exceeding the level effective against microbes, exposed to whole body in rats continuously for six months was not toxic, under a condition simulating the conventional lifestyle in human.

  14. Acute and Short-Term Inhalation Toxicity Study of FT Fuel

    Science.gov (United States)

    2011-02-01

    than JP-8 in equivalent tests . In addition, micronucleus induction was tested ; FT jet fuel does not induce micronuclei, indicating that the fuel is...OECD, 1981). A separate group of rats were used as controls for assessment of micronucleus induction in order to complete the genotoxicity testing of...toxicity study in F344 rats was investigated in a short-term mutagenicity assay, the mammalian erythrocyte micronucleus (MN) test . Animals were exposed

  15. Acute Inhalation Toxicity Study of 1, 4-Dioxane in Rats (Rattus norvegicus)

    Science.gov (United States)

    2012-07-01

    of degenerative and/or toxic nephropathy . Degenerative nephropathy is not uncommon in rats and is due to the predisposing factors of age, sex...was attributed to early and more acute progression of chronic progressive glomerular nephropathy . 4.2.6 Statistical Analysis: A statistical...0.6084 Degeneration 1 day M - - - - - - - F 0.0011 - - 0.0256 - 0.0256 0.0256 2 wk M - - - - - - - F - - - - - - - Kidney Nephropathy

  16. Acute toxicity assessment of choline by inhalation, intraperitoneal and oral routes in Balb/c mice.

    Science.gov (United States)

    Mehta, Amit Kumar; Arora, Naveen; Gaur, Shailendra Nath; Singh, Bhanu Pratap

    2009-08-01

    Studies suggest that choline has potential to be used as a dietary supplement and a drug for immune inflammatory diseases like asthma and rhinitis. But there are apprehensions regarding adverse effects of choline when given orally in high doses. To address this knowledge gap, toxicity assessment of choline chloride was carried out by intranasal (i.n.), oral and intraperitoneal (i.p.) routes in Balb/c mice for 28days. Body weight, food and water consumption of mice were recorded daily. Hematology and clinical chemistry were assessed to check hepatocellular functions and morphological alterations of the cells. Splenocyte counts were analysed for evaluating cellular immunity. Liver function test was performed by assaying different enzyme systems in serum such as, urea, blood urea nitrogen (BUN), creatinine, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Body weight, food and water consumption did not differ between mice treated with choline and the saline control group. Hematologic and biochemical variables were not affected with any increase in serum toxicity marker enzymes indicating normal liver functioning. Choline administration did not affect total cholesterol and high density lipoprotein levels as compared to their respective controls. Urea and blood urea nitrogen levels in choline treated mice were not different than controls. Creatinine level was, however, higher than control in i.p. treatment group, but other parameters were normal. In conclusion, the repeated consumption of choline chloride via i.n. and oral or i.p. routes did not cause toxicity in mice in the toxicological endpoints examined.

  17. Inhalation developmental toxicology studies: Developmental toxicity of chloroprene vapors in New Zealand white rabbits. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mast, T.J.; Evanoff, J.J.; Westerberg, R.B.; Rommereim, R.L.; Weigel, R.J.

    1994-04-01

    Chloroprene, 2-chloro-1,3-butadiene, is a colorless liquid with a pungent ethereal odor that is primarily used as an intermediate in the manufacture of neoprene rubber, and has been used as such since about 1930. This study addressed the potential for chloroprene to cause developmental toxicity in New Zealand white rabbits following gestational exposure to 0, 10, 40, or 175 ppm chloroprene vapors, 6h/dy, 7dy/wk. Each treatment group consisted of 15 artificially inseminated females exposed on 6 through 28 days of gestation (dg). Body weights were obtained throughout the study period, and uterine and fetal body weights were obtained at sacrifice on 29 dg. Implants were enumerated and their status recorded and live fetuses were examined for gross, visceral, skeletal, and soft-tissue craniofacial defects. There were no overt signs of maternal toxicity and the change in maternal body weight over the course of the study was not affected. Exposure of pregnant rabbits to chloroprene vapors on 6-28 dg had no effect on the number of implantation, the mean percent of live pups per litter, or on the incidence of resorptions per litter. The incidence of fetal malformations was not increased by exposure to chloroprene. Results of this study indicate that gestational exposure of New Zealand white rabbits to 10, 40, or 175 ppm chloroprene did not result in observable toxicity to either the dam or the offspring.

  18. Tolerance to various toxicants by marine bacteria highly resistant to mercury

    Digital Repository Service at National Institute of Oceanography (India)

    De, J.; Ramaiah, N.; Mesquita, A.; Verlecar, X.N.

    Bacteria highly resistant to mercury isolated from seawater and sediment samples were tested for growth in the presence of different heavy metals, pesticides, phenol, formaldehyde, formic acid, and trichloroethane to investigate their potential...

  19. Acute Inhalation Toxicity Test of Ivermectin Raw Powder%伊维菌素原粉急性吸入毒性试验研究

    Institute of Scientific and Technical Information of China (English)

    胡成云; 林师道; 纪磊; 汪建良; 张武; 岑江杰

    2016-01-01

    To study the acute inhalation toxicity of Ivermectin raw powder and provide the basis for safe use,limit test,the dose group was 2000 mg/m3 ,dynamic nose-only exposure,effective exposure time for 2 h.The results showed that ivermectin raw powder in male and female rats acute inhalation median lethal concentration (LC50 ) were more than 2089 mg/m3 .The acute inhalation toxicity was low toxicity.%对伊维菌素原粉急性吸入毒性进行研究,采用限量试验,设定2000 mg/m3一个剂量组,动式口鼻式染毒,有效染毒时间2h.结果显示,伊维菌素原粉对雌雄大鼠的急性吸入半数致死浓度(LC50)均大于2089 mg/m3.伊维菌素原粉急性吸入毒性属低毒,该结论为安全使用提供了依据.

  20. Inorganic and organic mercury chloride toxicity to Coturnix: Sensitivity related to age and quantal assessment of physiologic responses

    Science.gov (United States)

    Hill, E.F.

    1982-01-01

    The toxicities of mercuric chloride (HgCl(,2)) and methylmercuric chloride (CH(,3)HgCl) were compared for coturnix (Coturnix coturnix japonica) from hatching to adulthood. Comparisons were based on: (1) Median lethal dosages (LD50) derived by administering single peroral and single intramuscular dosages of mercury, (2) median lethal concentrations (LC50) derived by feeding mercury for 5 days, (3) median toxic concentrations (TC50) derived by feeding mercury 9 weeks and measuring plasma enzyme activity, plasma electrolytes, and other blood constituents, and (4) transient changes of various blood chemistries following a single peroral dose of mercury. Acute peroral and intramuscular LD50s for HgCl(,2) and CH(,3)HgCl increased by two- to threefold for coturnix chicks from hatching to 4 weeks of age. Concomitantly, the LC50s also increased, but the important difference between test procedures was that with both single dose routes of exposure the toxicity ratios, i.e., HgCl(,2)/CH(,3)HgCl, at each age were about 2 to 2.5 compared to about 100 for the LC50s. For example, at 2 weeks of age the peroral LD50s for HgCl(,2) and CH(,3)HgCl were 42 and 18 mg/kg; the dietary LC50s were 5086 and 47 ppm for HgCl(,2) and CH(,3)HgCl. The 9 week feeding trial was not associated with gross effects from either HgCl(,2) at 0.5 to 32 ppm or CH(,3)HgCl at 0.125 to 8 ppm. However, subtle responses were detected for the plasma enzymes aspartate aminotransferase, lactate dehydrogenase, and ornithine carbamoyl transferase and could be quantified by probit analysis. This quantal procedure was based on establishment of a normal value for each enzyme and classing outliers as respondents. A 'hazard index' based on the TC50 for an enzyme divided by the LD50 or LC50 was introduced. The single oral dosages of HgCl(,2) and CH(,3)HgCl showed that ratios of alanine aminotransferase, lactate dehydrogenase, and orinthine carbamoyl transferase for the liver and kidneys of adult coturnix were opposite from

  1. Determination of toxic elements (mercury, cadmium, lead, tin and arsenic) in fish and shellfish samples. Risk assessment for the consumers.

    Science.gov (United States)

    Olmedo, P; Pla, A; Hernández, A F; Barbier, F; Ayouni, L; Gil, F

    2013-09-01

    Although fish intake has potential health benefits, the presence of metal contamination in seafood has raised public health concerns. In this study, levels of mercury, cadmium, lead, tin and arsenic have been determined in fresh, canned and frozen fish and shellfish products and compared with the maximum levels currently in force. In a further step, potential human health risks for the consumers were assessed. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for their toxic elements content. High mercury concentrations were found in some predatory species (blue shark, cat shark, swordfish and tuna), although they were below the regulatory maximum levels. In the case of cadmium, bivalve mollusks such as canned clams and mussels presented higher concentrations than fish, but almost none of the samples analyzed exceeded the maximum levels. Lead concentrations were almost negligible with the exception of frozen common sole, which showed median levels above the legal limit. Tin levels in canned products were far below the maximum regulatory limit, indicating that no significant tin was transferred from the can. Arsenic concentrations were higher in crustaceans such as fresh and frozen shrimps. The risk assessment performed indicated that fish and shellfish products were safe for the average consumer, although a potential risk cannot be dismissed for regular or excessive consumers of particular fish species, such as tuna, swordfish, blue shark and cat shark (for mercury) and common sole (for lead).

  2. Synthesis and spectral characterization of silver embedded chitosan matrix nanocomposite for the selective colorimetric sensing of toxic mercury

    Science.gov (United States)

    Nivethaa, E. A. K.; Narayanan, V.; Stephen, A.

    2015-05-01

    Polymer matrix type chitosan-silver nanocomposite containing different weight percentage of silver was synthesized by the chemical method. HRTEM images confirm the embedment of silver in the chitosan matrix. The binding of silver to the NH2 and OH groups of chitosan is evident from XPS and FTIR studies. An increase in the absorbance observed from UV-Vis analysis on raising the weight percentage of silver showed the increase in the amount of silver in the nanocomposite. The face centered cubic structure of silver and the semi-crystalline nature of chitosan are evident from the XRD studies. On interaction with mercury the UV-Vis spectra of the composite showed a decrease in intensity and a blue shift confirming the use of the composite as a colorimetric sensor for the detection of mercury. The limit of detection was found to be about 7.2 × 10-8 M. High specificity and the sensitivity of the environmental friendly and non-toxic nanocomposite to detect very low concentrations of mercury make the system a perspective one.

  3. Adsorption of toxic mercury(II) by an extracellular biopolymer poly(gamma-glutamic acid).

    Science.gov (United States)

    Inbaraj, B Stephen; Wang, J S; Lu, J F; Siao, F Y; Chen, B H

    2009-01-01

    Adsorption of mercury(II) by an extracellular biopolymer, poly(gamma-glutamic acid) (gamma-PGA), was studied as a function of pH, temperature, agitation time, ionic strength, light and heavy metal ions. An appreciable adsorption occurred at pH>3 and reached a maximum at pH 6. Isotherms were well predicted by Redlich-Peterson model with a dominating Freundlich behavior, implying the heterogeneous nature of mercury(II) adsorption. The adsorption followed an exothermic and spontaneous process with increased orderliness at solid/solution interface. The adsorption was rapid with 90% being attained within 5 min for a 80 mg/L mercury(II) solution, and the kinetic data were precisely described by pseudo second order model. Ionic strength due to added sodium salts reduced the mercury(II) binding with the coordinating ligands following the order: Cl(-) >SO(4)(2-) >NO(3)(-). Both light and heavy metal ions decreased mercury(II) binding by gamma-PGA, with calcium(II) ions showing a more pronounced effect than monovalent sodium and potassium ions, while the interfering heavy metal ions followed the order: Cu(2+) > Cd(2+) > Zn(2+). Distilled water adjusted to pH 2 using hydrochloric acid recovered 98.8% of mercury(II), and gamma-PGA reuse for five cycles of operation showed a loss of only 6.5%. IR spectra of gamma-PGA and Hg(II)-gamma-PGA revealed binding of mercury(II) with carboxylate and amide groups on gamma-PGA.

  4. Toxicity of inhaled particulate matter on the central nervous system: neuroinflammation, neuropsychological effects and neurodegenerative disease.

    Science.gov (United States)

    Wang, Yan; Xiong, Lilin; Tang, Meng

    2017-03-16

    Particulate matter (PM) combined with meteorological factors cause the haze, which brings inconvenience to people's daily life and deeply endanger people's health. Accumulating literature, to date, reported that PM are closely related to cardiopulmonary disease. Outpatient visits and admissions as a result of asthma and heart attacks gradually increase with an elevated concentration of PM. Owing to its special physicochemical property, the brain could be a potential target beyond the cardiopulmonary system. Possible routes of PM to the brain via a direct route or stimulation of pro-inflammatory cytokines have been reported in several documents concerning toxicity of engineered nanoparticles in rodents. Recent studies have demonstrated that PM have implications in oxidative stress, inflammation, dysfunction of cellular organelles, as well as the disturbance of protein homeostasis, promoting neuron loss and exaggerating the burden of central nervous system (CNS). Moreover, the smallest particles (nano-sized particles), which were involved in inflammation, reactive oxygen species (ROS), microglial activation and neuron loss, may accelerate the process of the neurodevelopmental disorder and neurodegenerative disease. Potential or other undiscovered mechanisms are not mutually exclusive but complementary aspects of each other. Epidemiology studies have shown that exposure to PM could bring about neurotoxicity and play a significant role in the etiology of CNS disease, which has been gradually corroborated by in vivo and in vitro studies. This review highlights research advances on the health effects of PM with an emphasis on neurotoxicity. With the hope of enhancing awareness in the public and calling for prevention and protective measures, it is a critical topic that requires proceeding exploration. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Reasons for Inhalant Use.

    Science.gov (United States)

    Joe, George W.; Simpson, D. Dwayne

    1991-01-01

    Among 110 Mexican-American adolescents in a Texas drug abuse program, initial use of toxicant inhalants was related to availability and sensation-seeking, followed by psychological problems, parental and home problems, and peer influence. Quitting inhalant use was related to social pressures, attitude change, and perceived health risks. (Author/SV)

  6. Mercury poisoning in two 13-year-old twin sisters.

    Science.gov (United States)

    Khodashenas, Ezzat; Aelami, Mohammadhassan; Balali-Mood, Mahdi

    2015-03-01

    Mercury (Hg) is a toxic agent that evaporates in room temperature and its inhalation may cause poisoning. Due to the nonspecific symptoms, diagnosis is difficult in special circumstances with no initial history of Hg exposure. We report two such cases of Hg poisoning. The patients were two sisters, presenting with pain in extremities, itchy rashes, sweating, salivation, weakness, and mood changes. They have used a compound that contains mercury, for treatment of pedicullosis three months before admission. This compound was purchased from a herbal shop and was applied locally on the scalps for 2 days. Their urinary mercury concentrations were 50 and 70 mg/L. They were successfully treated by D-penicillamine and gabapentin. In a patient with any kind of bone and joint pain, skin rash erythema and peripheral neuropathy, mercury poisoning should be considered as a differential diagnosis.

  7. Mercury poisoning in two 13-year-old twin sisters

    Directory of Open Access Journals (Sweden)

    Ezzat Khodashenas

    2015-01-01

    Full Text Available Mercury (Hg is a toxic agent that evaporates in room temperature and its inhalation may cause poisoning. Due to the nonspecific symptoms, diagnosis is difficult in special circumstances with no initial history of Hg exposure. We report two such cases of Hg poisoning. The patients were two sisters, presenting with pain in extremities, itchy rashes, sweating, salivation, weakness, and mood changes. They have used a compound that contains mercury, for treatment of pedicullosis three months before admission. This compound was purchased from a herbal shop and was applied locally on the scalps for 2 days. Their urinary mercury concentrations were 50 and 70 mg/L. They were successfully treated by D-penicillamine and gabapentin. In a patient with any kind of bone and joint pain, skin rash erythema and peripheral neuropathy, mercury poisoning should be considered as a differential diagnosis.

  8. Comparative short-term inhalation toxicity of five organic diketopyrrolopyrrole pigments and two inorganic iron-oxide-based pigments

    Science.gov (United States)

    Hofmann, Thomas; Ma-Hock, Lan; Strauss, Volker; Treumann, Silke; Rey Moreno, Maria; Neubauer, Nicole; Wohlleben, Wendel; Gröters, Sibylle; Wiench, Karin; Veith, Ulrich; Teubner, Wera; van Ravenzwaay, Bennard; Landsiedel, Robert

    2016-01-01

    Abstract Diketopyrrolopyrroles (DPP) are a relatively new class of organic high-performance pigments. The present inhalation and particle characterization studies were performed to compare the effects of five DPP-based pigments (coarse and fine Pigment Red 254, coarse and fine meta-chloro DPP isomer and one form of mixed chlorinated DPP isomers) and compare it to coarse and fine inorganic Pigment Red 101. Wistar rats were exposed head-nose to atmospheres of the respective materials for 6 h/day on 5 consecutive days. Target concentrations were 30 mg/m3 as high dose for all compounds and selected based occupational exposure limits for respirable nuisance dust. Toxicity was determined after end of exposure and after 3-week recovery using broncho-alveolar lavage fluid (BALF) and microscopic examinations of the entire respiratory tract. Mixed chlorinated DPP isomers and coarse meta-chloro DPP isomer caused marginal changes in BALF, consisting of slight increases of polymorphonuclear neutrophils, and in case of coarse meta-chloro DPP increased MCP-1 and osteopontin levels. Mixed chlorinated DPP isomers, Pigment Red 254, and meta-chloro DPP caused pigment deposits and phagocytosis by alveolar macrophages, slight hypertrophy/hyperplasia of the bronchioles and alveolar ducts, but without evidence of inflammation. In contrast, only pigment deposition and pigment phagocytosis were observed after exposure to Pigment Red 101. All pigments were tolerated well and caused only marginal effects in BALF or no effects at all. Only minor effects were seen on the lung by microscopic examination. There was no evidence of systemic inflammation based on acute-phase protein levels in blood. PMID:27387137

  9. Twenty-eight-day repeated inhalation toxicity study of nano-sized lanthanum oxide in male sprague-dawley rats.

    Science.gov (United States)

    Shin, Seo-Ho; Lim, Cheol-Hong; Kim, Yong-Soon; Lee, Yong-Hoon; Kim, Sung-Hwan; Kim, Jong-Choon

    2017-04-01

    Although the use of lanthanum has increased in field of high-tech industry worldwide, potential adverse effects to human health and to the environment are largely unknown. The present study aimed to investigate the potential toxicity of nano-sized lanthanum oxide (La2 O3 ) following repeated inhalation exposure in male Sprague-Dawley rats. Male rats were exposed nose-only to nano-sized La2 O3 for 28 days (5 days/week) at doses of 0, 0.5, 2.5, and 10 mg/m(3) . In the experimental period, we evaluated treatment-related changes including clinical signs, body weight, hematology, serum biochemistry, necropsy findings, organ weight, and histopathology findings. We also analyzed lanthanum distribution in the major organs and in the blood, bronchoalveolar lavage fluids (BALF), and oxidative stress in lung tissues. Lanthanum level was highest in lung tissues and showed a dose-dependent relation. Alveolar proteinosis was observed in all treatment groups and was accompanied by an increase in lung weight; moreover, lung inflammation was observed in the 2.5 mg/m(3) and higher dose groups and was accompanied by an increase in white blood cells. In the BALF, total cell counts including macrophages and neutrophils, lactate dehydrogenase, albumin, nitric oxide, and tumor necrosis factor-alpha increased significantly in all treatment groups. Furthermore, these changes tended to deteriorate in the 10 mg/m(3) group at the end of the recovery period. In the present experimental conditions, we found that the lowest-observed-adverse-effect level of nano-sized La2 O3 was 0.5 mg/m(3) in male rats, and the target organ was the lung. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1226-1240, 2017. © 2016 Wiley Periodicals, Inc.

  10. Acute toxic effects of nerve agent VX on respiratory dynamics and functions following microinsillation inhalation exposure in guinea pigs.

    Science.gov (United States)

    Rezk, Peter E; Graham, Jacob R; Moran, Theodore S; Gordon, Richard K; Sciuto, Alfred M; Doctor, Bhupendra P; Nambiar, Madhusoodana P

    2007-03-01

    Exposure to a chemical warfare nerve agent (CWNA) leads to severe respiratory distress, respiratory failure, or death if not treated. We investigated the toxic effects of nerve agent VX on the respiratory dynamics of guinea pigs following exposure to 90.4 mug/m3 of VX or saline by microinstillation inhalation technology for 10 min. Respiratory parameters were monitored by whole-body barometric plethysmography at 4, 24, and 48 h, 7 d, 18 d, and 4 wk after VX exposure. VX-exposed animals showed a significant decrease in the respiratory frequency (RF) at 24 and 48 h of recovery (p value .0329 and .0142, respectively) compared to the saline control. The tidal volume (TV) slightly increased in VX exposed animals at 24 and significantly at 48 h (p = .02) postexposure. Minute ventilation (MV) increased slightly at 4 h but was reduced at 24 h and remained unchanged at 48 h. Animals exposed to VX also showed an increase in expiratory (Te) and relaxation time (RT) at 24 and 48 h and a small reduction in inspiratory time (Ti) at 24 h. A significant increase in end expiratory pause (EEP) was observed at 48 h after VX exposure (p = .049). The pseudo lung resistance (Penh) was significantly increased at 4 h after VX exposure and remained slightly high even at 48 h. Time-course studies reveal that most of the altered respiratory dynamics returned to normal at 7 d after VX exposure except for EEP, which was high at 7 d and returned to normal at 18 d postexposure. After 1 mo, all the monitored respiratory parameters were within normal ranges. Bronchoalveolar lavage (BAL) 1 mo after exposure showed virtually no difference in protein levels, cholinesterase levels, cell number, and cell death in the exposed and control animals. These results indicate that sublethal concentrations of VX induce changes in respiratory dynamics and functions that over time return to normal levels.

  11. Spontaneous and Dosing Route-related Lung Lesions in Beagle Dogs from Oral Gavage and Inhalation Toxicity Studies: Differentiation from Compound-induced Lesions.

    Science.gov (United States)

    Mukaratirwa, Sydney; Garcia, Begonya; Isobe, Kaori; Petterino, Claudio; Bradley, Alys

    2016-10-01

    This study was conducted to characterize lung microscopic lesions in control beagle dogs from inhalation and oral gavage toxicity studies, to determine differences associated with the route of administration, and to discuss distinguishing features from compound-induced lung lesions. Samples from 138 control dogs from oral gavage studies and 124 control dogs from inhalation (vehicle control) studies were evaluated microscopically. There was no significant sex-related difference in the incidence of all lesions. Perivascular mononuclear cell infiltration, centriacinar mixed cell infiltration, bronchopneumonia, subpleural septal fibrosis, and alveolar macrophage accumulation were the most common lesions. Aspiration pneumonia was more common in dogs from gavage studies, suggesting reflux after gavage dosing or accidental administration of test formulation as possible causes. Centriacinar mixed cell infiltration was more common in dogs from inhalation studies, suggesting mild irritation by the vehicles used. Vascular lesions, which included pulmonary arteriopathy and smooth muscle mineralization, were observed in a few animals. Some of the spontaneous lesions are similar to lesions induced by test compounds. Compared to spontaneous lesions, compound-induced lesions tend to be multifocal or diffuse, follow a pattern of distribution (e.g., centriacinar, perivascular, and interstitial), show a dose response in the incidence and severity, and may show cell-specific toxicity.

  12. Toxicity evaluation of petroleum blending streams: inhalation subchronic toxicity/neurotoxicity study of a light catalytic cracked naphtha distillate in rats.

    Science.gov (United States)

    Lapin, C; Bui, Q; Breglia, R; Koschier, F; Podhasky, P; Lapadula, E; Roth, R; Schreiner, C; White, R; Clark, C; Mandella, R; Hoffman, G

    2001-01-01

    A 15-week, whole-body inhalation study of the vapors of a distillate (LCCN-D) of light catalytic cracked naphtha (CAS no. 64741-55-5, LCCN) was conducted with Sprague-Dawley rats. Target exposure concentrations were 0, 750, 2500, and 7500 ppm for 6 hours/day, 5 days/week. Over the course of the study, animals received at least 65 exposures. For a portion of the control and 7500-ppm groups, a 4-week postexposure period was included in the study. Subchronic toxicity was evaluated using standard parameters. During life, neurotoxicity was evaluated by motor activity assessment and a functional observational battery. Selected tissues from animals in all exposure groups were examined microscopically. Neuropathologic examination of selected neuronal tissues from animals in the control and high-exposure groups was also conducted. No compound-related effects were seen on survival, clinical chemistry, food consumption, or physical signs. No evidence of neurotoxicity was seen at any exposure level. Slight decreases in hematocrit and hemoglobin concentrations were seen in male rats at the end of exposure to 7500 ppm LCCN-D. However, values were within normal physiological ranges and recovery occurred. Slight decreases in mean body weights and body weight gain were observed in high-exposure females during the first 7 weeks of exposure, but this decrease was not seen during the second half of the study. Male rat nephropathy involving hyaline droplet formation and alpha-2micro-globulin accumulation was seen in mid- and high-exposure males, an effect not relevant to humans. The incidence and severity of goblet cell hypertrophy/hyperplasia and respiratory epithelium hyperplasia in nasoturbinal tissues were greater in high-exposure animals, but recovery occurred. None of the effects observed were considered toxicologically significant. The no-observable-adverse-effect level (NOAEL) for subchronic and neurotoxicity of LCCN-D was > or = 7500 ppm.

  13. Effect of water quality on mercury toxicity to Photobacterium phosphoreum: Model development and its application in natural waters.

    Science.gov (United States)

    Wang, Xinghao; Qu, Ruijuan; Wei, Zhongbo; Yang, Xi; Wang, Zunyao

    2014-06-01

    Mercury (Hg) compounds are widely distributed toxic environmental and industrial pollutants and they may bring danger to growth and development of aquatic organisms. The distribution of Hg species in the 3 percent NaCl solution was calculated using the chemical equilibrium model Visual MINTEQ, which demonstrated that Hg was mainly complexed by chlorides in the pH range 5.0-9.0 and the proportions of HgCl4(2-), HgCl3(-) and HgCl2(aq) reached to 95 percent of total Hg. Then the effects of cations (Ca(2+), Mg(2+), K(+) and H(+)), anions (HCO3(-), NO3(-), SO4(2-) and HPO4(2-)) and complexing agents (ethylene diamine tetraacetic acid (EDTA) and dissolved organic matter (DOM)) on Hg toxicity to Photobacterium phosphoreum were evaluated in standardized 15min acute toxicity tests. The significant increase of 6.3-fold in EC50 data with increasing pH was observed over the tested pH range of 5.0-8.0, which suggested the possible competition between hydroxyl and the negatively charged chloro-complex. By contrast, it was found that major cations (Ca(2+), Mg(2+) and K(+)) have little effect on Hg toxicity to P. phosphoreum. An interesting finding was that the addition of HPO4(2-) significantly increased Hg toxicity, which may imply that the addition of phosphate increased the soluble Hg-chloro complex species. Additions of complexing agents (EDTA and DOM) into the exposure water increased Hg bioavailability via complexation of Hg. Finally, a model which incorporated the effect of pH, HPO4(2-), HCO3(-), SO4(2-) and DOM on Hg toxicity was developed to predict acute Hg toxicity for P. phosphoreum, which may be a useful tool in setting realistic water quality criteria for different types of water.

  14. Toxicity evaluation of petroleum blending streams: inhalation subchronic toxicity/neurotoxicity study of a light catalytic reformed naphtha distillate in rats.

    Science.gov (United States)

    Schreiner, C; Bui, Q; Breglia, R; Burnett, D; Koschier, F; Lapadula, E; Podhasky, P; White, R

    2000-08-11

    A 13-wk whole-body inhalation study was conducted with Sprague-Dawley CD rats (16/sex/group) exposed to a light catalytic reformed naphtha distillate (LCRN-D, CAS number 64741-63-5) at target concentrations of 0, 750, 2500, and 7500 ppm for 6 h/d, 5 d/wk. Sixteen rats per sex in the control and high-dose groups were maintained after final exposure for a 4-wk recovery period. The highest exposure concentration was 75% of the lower explosive limit. Standard parameters of subchronic toxicity were measured throughout the study; at necropsy, organs were weighed and tissues processed for microscopic evaluation. Neurotoxicity evaluations consisted of motor activity (MA) and a functional operational battery (FOB) measured pretest, throughout exposure and after the recovery period. Neuropathology was evaluated at termination. No test-related mortality or effects on physical signs, body weight, food consumption, or clinical chemistry were observed. In males exposed to 7500-ppm LCRN-D, a statistically significant decrease in white blood cell counts and lymphocyte counts was observed at the termination of exposure that was not present in animals after the 4-wk recovery period. However, mean corpuscular volume was slightly decreased in high-dose males after the recovery period. Statistically significant increases in kidney weights relative to body weights in 7500-ppm male rats correlated with microscopically observed hyaline droplet formation and renal tubule dilation, indicative of light hydrocarbon nephropathy, a condition in male rats that is not toxicologically significant for humans. Statistically significant decrease in absolute and relative spleen weights in 7500-ppm male rats correlated with decreases in hematologic parameters but had no microscopic correlate and was not observed in animals after 4 wk of recovery. This mild, reversible effect in white blood cell populations may relate to the presence of aromatics in the distillate. The only effect of LCRN-D on

  15. On the chalcogenophilicity of mercury: evidence for a strong Hg-Se bond in [Tm(Bu(t))]HgSePh and its relevance to the toxicity of mercury.

    Science.gov (United States)

    Melnick, Jonathan G; Yurkerwich, Kevin; Parkin, Gerard

    2010-01-20

    One of the reasons for the toxic effects of mercury has been attributed to its influence on the biochemical roles of selenium. For this reason, it is important to understand details pertaining to the nature of Hg-Se interactions and this has been achieved by comparison of a series of mercury chalcogenolate complexes that are supported by tris(2-mercapto-1-t-butyl-imidazolyl)hydroborato ligation, namely [Tm(Bu(t))]HgEPh (E = S, Se, Te). In particular, X-ray diffraction studies on [Tm(Bu(t))]HgEPh demonstrate that although the Hg-S bonds involving the [Tm(Bu(t))] ligand are longer than the corresponding Cd-S bonds of [Tm(Bu(t))]CdEPh, the Hg-EPh bonds are actually shorter than the corresponding Cd-EPh bonds, an observation which indicates that the apparent covalent radii of the metals in these compounds are dependent on the nature of the bonds. Furthermore, the difference in Hg-EPh and Cd-EPh bond lengths is a function of the chalcogen and increases in the sequence S (0.010 A) selenolate transfer from zinc to mercury upon treatment of [Tm(Bu(t))]HgSCH(2)C(O)N(H)Ph with [Tm(Bu(t))]ZnSePh. The significant selenophilicity of mercury is in accord with the aforementioned proposal that one reason for the toxicity of mercury is associated with it reducing the bioavailability of selenium.

  16. Global Proteome Profiling of a Marine Copepod and the Mitigating Effect of Ocean Acidification on Mercury Toxicity after Multigenerational Exposure.

    Science.gov (United States)

    Wang, Minghua; Lee, Jae-Seong; Li, Yan

    2017-05-16

    Previously, we found that ocean acidification (OA) mitigates mercury (Hg) toxicity to marine copepod Tigriopus japonicus under multigenerational exposure (four generations, F0-F3). To determine the response mechanisms of T. japonicus against long-term exposure to OA and Hg pollution, we investigated the proteome of F3 copepods after multigenerational exposure to four conditions: pCO2 400 μatm + control; pCO2 1000 μatm + control; pCO2 400 μatm +1.0 μg/L Hg; and pCO2 1000 μatm +1.0 μg/L Hg. Functional enrichment analysis indicated that OA enhanced the copepod's energy production mainly by increasing protein assimilation and proteolysis as a compensatory strategy, which explained its physiological resilience to reduced pH. Conversely, Hg treatment decreased many critical processes, including ferric iron binding, antioxidant activity, cellular homeostasis, and glutathione metabolism, and these toxic events could translate into higher-level responses, i.e., restrained reproduction in copepods. Importantly, the mediation of Hg toxicity in T. japonicus by OA could be explained by the enhanced lysosome-autophagy pathway proteomes that are responsible for repairing and removing damaged proteins and enzymes under stress. Overall, this study provided molecular insights into the response of T. japonicus to long-term exposure of OA and Hg, with a particular emphasis on the mitigating impact of the CO2-driven acidification on Hg toxicity.

  17. REPRODUCTIVE TOXICITY OF CHLORPYRIFOS, DIELDRIN, AND METHYL MERCURY MIXTURES TO THE AMPHIPOD, HYALELLA AZTECA

    Science.gov (United States)

    Toxicological interactions were assessed on the reproduction of the amphipod Hyalella azteca throughout a chronic exposure to methyl mercury (0.9, 4.7, 23.3 nM), chlorpyrifos (0.01, 0.05, 0.24), dieldrin (0.5, 2.3, 11.4 nM) and their binary mixtures. H. azteca were exposed to the...

  18. DMPS (DIMAVAL) as a challenge test to assess the mercury and arsenic body/kidney load in humans and as a treatment of mercury toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Aposhian, H.V.; Maiorino, R.M.; Aposhian, M.M. [Univ. of Arizona, Tucson, AZ (United States); Hurlbut, K.M. [Rocky Mountain Poison Control Center, Denver, CO (United States)] [and others

    1996-12-31

    Mercury is an element which, with its compounds, is hazardous and is found in hazardous wastes. In Order to develop suitable diagnostic and therapeutic agents for mercury exposure, we have sought alternative test systems. We have used the chelating agent 2,3-dimercaptopropane-1-sulfonate (DMPS, DIMAVAL{reg_sign}) for estimating the body burden of mercury in normal humans and in dental personnel in a developing country, and for detoxifying humans with mercurous chloride exposure. Use of the DMPS-mercury challenge test has shown that two-thirds of the mercury excreted in the urine of volunteers with dental amalgams appears to be derived from the mercury vapor released from their amalgams. The DMPS challenge test (300 mg, by mouth, after an 11 hr fast) was useful for monitoring dental personnel for mercury vapor exposure. The DMPS challenge test was given to 11 factory workers who make a skin lotion that contains mercurous chloride, 8 users of the skin lotion, and 9 controls. The increases in urinary Hg resulting from the DMPS challenge were 45, 87, and 38-fold, respectively. The results demonstrate that in humans exposed to mercurous chloride, the DMPS-mercury challenge test is of value for a more realistic estimation of mobilizable Hg. DMPS should be considered for use to determine mercury body burdens and to treat humans exposed to mercury and its compounds via exposure to hazardous wastes. 42 refs., 2 figs., 5 tabs.

  19. Sediment toxicity and bioaccumulation assessment in abandoned copper and mercury mining areas of the Nalón River basin (Spain).

    Science.gov (United States)

    Méndez-Fernández, L; Rodríguez, P; Martínez-Madrid, M

    2015-01-01

    Sediment toxicity and metal bioaccumulation were assessed at sites affected by historical copper (Cu) and mercury (Hg) mining activities in the Nalón River basin, Asturias, Spain. Toxicity assessment of stream sediments was based on a 28-day oligochaete Tubifex tubifex sediment bioassay, which allowed the classification of sites into three levels of toxicity: 11 sites were classified as nontoxic (including Cu mine sites), three sites as potentially toxic, and seven sites as toxic (all located in Hg mine districts). The greatest levels of arsenic (As), chromium, Hg, lead (Pb), and zinc (Zn) in T. tubifex were measured at sites affected by Hg mining and the highest Cu levels in tissues at Cu mining sites. Chronic toxicity responses were best explained by As and Hg sediment concentrations and by As, Pb, and Zn tissue residues. Residue levels of As, Hg, Zn, and Pb were successfully used to predict sediment chronic toxicity and estimate effective tissue residues.

  20. Integrating toxicity risk in bird eggs and chicks: Using chick down feathers to estimate mercury concentrations in eggs

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2009-01-01

    The concentration of mercury (Hg) in eggs that causes reduced hatching success is regarded as a critical end point for Hg toxicity in birds. However, incorporating effects of in ovo mercury exposure on chick health and survival could improve risk assessment. We developed equations to predict Hg in eggs using Hg in chick down feathers, and vice versa, by assessing the relationship between Hg in feathers (0.5−32.4 μg g−1 fw) and eggs (0.04−2.79 μg g−1 fww) for three waterbird species in San Francisco Bay, CA. Feather Hg sampled from embryos of pipping eggs was highly correlated with fresh whole-egg Hg (n = 94, r2 = 0.96). Additionally, using an egg microsampling technique, albumen Hg was correlated with feather Hg sampled from chicks in the same nest (n = 28, r2 = 0.79). Down feather Hg in recaptured chicks (≤10 days old) was correlated with down feather Hg at hatching (≤3 days old; n = 88, r2 = 0.74). Our results demonstrate the utility of using down feathers of chicks ≤10 days of age to nonlethally predict Hg in eggs and thus provide the ability to develop exposure thresholds for eggs that incorporate in ovo Hg’s effects on both egg hatchability and subsequent chick mortality.

  1. Removal of Toxic Mercury from Petroleum Oil by Newly Synthesized Molecularly-Imprinted Polymer

    OpenAIRE

    Nor Ain Shahera Khairi; Nor Azah Yusof; Abdul Halim Abdullah; Faruq Mohammad

    2015-01-01

    In recent years, molecularly-imprinted polymers (MIPs) have attracted the attention of several researchers due to their capability for molecular recognition, easiness of preparation, stability and cost-effective production. By taking advantage of these facts, Hg(II) imprinted and non-imprinted copolymers were prepared by polymerizing mercury nitrate stock solution (or without it) with methacrylic acid (MAA), 2-hydroxyl ethyl methacrylate (HEMA), methanol and ethylene glycol dimethacrylate (E...

  2. Mercury and health care

    Directory of Open Access Journals (Sweden)

    Rustagi Neeti

    2010-01-01

    Full Text Available Mercury is toxic heavy metal. It has many characteristic features. Health care organizations have used mercury in many forms since time immemorial. The main uses of mercury are in dental amalgam, sphygmomanometers, and thermometers. The mercury once released into the environment can remain for a longer period. Both acute and chronic poisoning can be caused by it. Half of the mercury found in the atmosphere is human generated and health care contributes the substantial part to it. The world has awakened to the harmful effects of mercury. The World Health Organization and United Nations Environmental Programme (UNEP have issued guidelines for the countries′ health care sector to become mercury free. UNEP has formed mercury partnerships between governments and other stakeholders as one approach to reducing risks to human health and the environment from the release of mercury and its compounds to the environment. Many hospitals are mercury free now.

  3. Mercury and health care

    Science.gov (United States)

    Rustagi, Neeti; Singh, Ritesh

    2010-01-01

    Mercury is toxic heavy metal. It has many characteristic features. Health care organizations have used mercury in many forms since time immemorial. The main uses of mercury are in dental amalgam, sphygmomanometers, and thermometers. The mercury once released into the environment can remain for a longer period. Both acute and chronic poisoning can be caused by it. Half of the mercury found in the atmosphere is human generated and health care contributes the substantial part to it. The world has awakened to the harmful effects of mercury. The World Health Organization and United Nations Environmental Programme (UNEP) have issued guidelines for the countries’ health care sector to become mercury free. UNEP has formed mercury partnerships between governments and other stakeholders as one approach to reducing risks to human health and the environment from the release of mercury and its compounds to the environment. Many hospitals are mercury free now. PMID:21120080

  4. Mercury and health care.

    Science.gov (United States)

    Rustagi, Neeti; Singh, Ritesh

    2010-08-01

    Mercury is toxic heavy metal. It has many characteristic features. Health care organizations have used mercury in many forms since time immemorial. The main uses of mercury are in dental amalgam, sphygmomanometers, and thermometers. The mercury once released into the environment can remain for a longer period. Both acute and chronic poisoning can be caused by it. Half of the mercury found in the atmosphere is human generated and health care contributes the substantial part to it. The world has awakened to the harmful effects of mercury. The World Health Organization and United Nations Environmental Programme (UNEP) have issued guidelines for the countries' health care sector to become mercury free. UNEP has formed mercury partnerships between governments and other stakeholders as one approach to reducing risks to human health and the environment from the release of mercury and its compounds to the environment. Many hospitals are mercury free now.

  5. Modeling potential occupational inhalation exposures and associated risks of toxic organics from chemical storage tanks used in hydraulic fracturing using AERMOD.

    Science.gov (United States)

    Chen, Huan; Carter, Kimberly E

    2017-05-01

    Various toxic chemicals used in hydraulic fracturing fluids may influence the inherent health risks associated with these operations. This study investigated the possible occupational inhalation exposures and potential risks related to the volatile organic compounds (VOCs) from chemical storage tanks and flowback pits used in hydraulic fracturing. Potential risks were evaluated based on radial distances between 5 m and 180 m from the wells for 23 contaminants with known inhalation reference concentration (RfC) or inhalation unit risks (IUR). Results show that chemicals used in 12.4% of the wells posed a potential acute non-cancer risks for exposure and 0.11% of the wells with may provide chronic non-cancer risks for exposure. Chemicals used in 7.5% of the wells were associated with potential acute cancer risks for exposure. Those chemicals used in 5.8% of the wells may be linked to chronic cancer risks for exposure. While eight organic compounds were associated with acute non-cancer risks for exposure (>1), methanol the major compound in the chemical storage tanks (1.00-45.49) in 7,282 hydraulic fracturing wells. Wells with chemicals additives containing formaldehyde exhibited both acute and chronic cancer risks for exposure with IUR greater than 10(-6), suggesting formaldehyde was the dominant contributor to both types of risks for exposure in hydraulic fracturing. This study also found that due to other existing on-site emission sources of VOCs and the geographically compounded air concentrations from other surrounding wells, chemical emissions data from storage tanks and flowback pits used in this study were lower than reported concentrations from field measurements where higher occupational inhalation risks for exposure may be expected.

  6. Using silver nano particles for sampling of toxic mercury vapors from industrial air sample

    Directory of Open Access Journals (Sweden)

    M. Osanloo

    2014-05-01

    .Conclusion: The presented adsorbent is very useful for sampling of the trace amounts of mercury vapors from air. Moreover, it can be regenerated easily is suitable or sampling at 25 to 70 °C. Due to oxidation of silver and reduction in uptake of nanoparticles, oven temperature of 245 °C is used for the recovery of metallic silver. Low amount of adsorbent, high absorbency, high repeatability for sampling, low cost and high accuracy are of the advantages of the presented method.

  7. Analysis of Air Toxics From NOAA WP-3 Aircraft Measurements During the TexAQS 2006 Campaign: Comparison With Emission Inventories and Additive Inhalation Risk Factors

    Science.gov (United States)

    Del Negro, L. A.; Warneke, C.; de Gouw, J. A.; Atlas, E.; Lueb, R.; Zhu, X.; Pope, L.; Schauffler, S.; Hendershot, R.; Washenfelder, R.; Fried, A.; Richter, D.; Walega, J. G.; Weibring, P.

    2007-12-01

    Benzene and nine other air toxics classified as human carcinogens by the International Agency for Research on Cancer (IARC) were measured from the NOAA WP-3 aircraft during the TexAQS 2006 campaign. In-situ measurements of benzene, measured with a PTR-MS instrument, are used to estimate emission fluxes for comparison with point source emission inventories developed by the Texas Commission on Environmental Quality. Mean and median mixing ratios for benzene, acetaldehyde, formaldehyde, 1,3-butadiene, carbon tetrachloride, chloroform, 1,2-dichloroethane, dibromoethane, dichloromethane, and vinyl chloride, encountered over the city of Houston during the campaign, are combined with inhalation unit risk factor values developed by the California Environmental Protection Agency and the United States Environmental Protection Agency to estimate the additive inhalation risk factor. This additive risk factor represents the risk associated with lifetime (70 year) exposure at the levels measured and should not be used as an absolute indicator of risk to individuals. However, the results are useful for assessments of changing relative risk over time, and for identifying dominant contributions to the overall air toxic risk.

  8. Organ burden and pulmonary toxicity of nano-sized copper (II) oxide particles after short-term inhalation exposure

    NARCIS (Netherlands)

    Gosens, Ilse; Cassee, Flemming R|info:eu-repo/dai/nl/143038990; Zanella, Michela; Manodori, Laura; Brunelli, Andrea; Costa, Anna Luisa; Bokkers, Bas G H|info:eu-repo/dai/nl/304847062; de Jong, Wim H; Brown, David; Hristozov, Danail; Stone, Vicki

    2016-01-01

    INTRODUCTION: Increased use of nanomaterials has raised concerns about the potential for undesirable human health and environmental effects. Releases into the air may occur and, therefore, the inhalation route is of specific interest. Here we tested copper oxide nanoparticles (CuO NPs) after

  9. Organ burden and pulmonary toxicity of nano-sized copper (II) oxide particles after short-term inhalation exposure

    NARCIS (Netherlands)

    Gosens, Ilse; Cassee, Flemming R; Zanella, Michela; Manodori, Laura; Brunelli, Andrea; Costa, Anna Luisa; Bokkers, Bas G H; de Jong, Wim H; Brown, David; Hristozov, Danail; Stone, Vicki

    2016-01-01

    INTRODUCTION: Increased use of nanomaterials has raised concerns about the potential for undesirable human health and environmental effects. Releases into the air may occur and, therefore, the inhalation route is of specific interest. Here we tested copper oxide nanoparticles (CuO NPs) after repeate

  10. Acute and Subchronic Toxicity of Inhaled Toluene in Male Long-Evans Rats: Oxidative Stress Markers in Brain

    Science.gov (United States)

    The effects of exposure to volatile organic compounds (VOCs), which are of concern to the EPA, are poorly understood, in part because of insufficient characterization of how human exposure duration impacts VOC effects. Two inhalation studies with multiple endpoints, one acute an...

  11. Acute and Subchronic Toxicity of Inhaled Toluene in Male Long-Evans Rats: Oxidative Stress Markers in Brain

    Science.gov (United States)

    The effects of exposure to volatile organic compounds (VOCs), which are of concern to the EPA, are poorly understood, in part because of insufficient characterization of how human exposure duration impacts VOC effects. Two inhalation studies with multiple endpoints, one acute an...

  12. Removal of Elemental Mercury from a Gas Stream Facilitated by a Non-Thermal Plasma Device

    Energy Technology Data Exchange (ETDEWEB)

    Charles Mones

    2006-12-01

    Mercury generated from anthropogenic sources presents a difficult environmental problem. In comparison to other toxic metals, mercury has a low vaporization temperature. Mercury and mercury compounds are highly toxic, and organic forms such as methyl mercury can be bio-accumulated. Exposure pathways include inhalation and transport to surface waters. Mercury poisoning can result in both acute and chronic effects. Most commonly, chronic exposure to mercury vapor affects the central nervous system and brain, resulting in neurological damage. The CRE technology employs a series of non-thermal, plasma-jet devices to provide a method for elemental mercury removal from a gas phase by targeting relevant chemical reactions. The technology couples the known chemistry of converting elemental mercury to ionic compounds by mercury-chlorine-oxygen reactions with the generation of highly reactive species in a non-thermal, atmospheric, plasma device. The generation of highly reactive metastable species in a non-thermal plasma device is well known. The introduction of plasma using a jet-injection device provides a means to contact highly reactive species with elemental mercury in a manner to overcome the kinetic and mass-transfer limitations encountered by previous researchers. To demonstrate this technology, WRI has constructed a plasma test facility that includes plasma reactors capable of using up to four plasma jets, flow control instrumentation, an integrated control panel to operate the facility, a mercury generation system that employs a temperature controlled oven and permeation tube, combustible and mercury gas analyzers, and a ductless fume hood designed to capture fugitive mercury emissions. Continental Research and Engineering (CR&E) and Western Research Institute (WRI) successfully demonstrated that non-thermal plasma containing oxygen and chlorine-oxygen reagents could completely convert elemental mercury to an ionic form. These results demonstrate potential the

  13. Signs and symptoms of mercury-exposed gold miners

    Directory of Open Access Journals (Sweden)

    Stephan Bose-O'Reilly

    2017-04-01

    Full Text Available Objectives: Gold miners use mercury to extract gold from ore adding liquid mercury to the milled gold-containing ore. This results in a mercury-gold compound, called amalgam. Miners smelt this amalgam to obtain gold, vaporizing it and finally inhaling the toxic mercury fumes. The objective was to merge and analyze data from different projects, to identify typical signs and symptoms of chronic inorganic mercury exposure. Material and Methods: Miners and community members from various artisanal small-scale gold mining areas had been examined (Philippines, Mongolia, Tanzania, Zimbabwe, Indonesia. Data of several health assessments were pooled. Urine, blood and hair samples were analyzed for mercury (N = 1252. Questionnaires, standardized medical examinations and neuropsychological tests were used. Participants were grouped into: Controls (N = 209, living in an exposed area (N = 408, working with mercury as panners (N = 181, working with mercury as amalgam burners (N = 454. Chi2 test, linear trend test, Mann-Whitney test, Kruskal-Wallis test, correlation coefficient, Spearman’s rho, and analysis of variance tests were used. An algorithm was used to define participants with chronic mercury intoxication. Results: Mean mercury concentrations in all exposed subgroups were elevated and above threshold limits, with amalgam burners showing highest levels. Typical symptoms of chronic metallic mercury intoxication were tremor, ataxia, coordination problems, excessive salivation and metallic taste. Participants from the exposed groups showed poorer results in different neuropsychological tests in comparison to the control group. Fifty-four percent of the high-exposed group (amalgam burners were diagnosed as being mercury-intoxicated, compared to 0% within the control group (Chi2 p < 0.001. Conclusions: Chronic mercury intoxication, with tremor, ataxia and other neurological symptoms together with a raised body burden of mercury was clinically diagnosed in

  14. Short term inhalation toxicity of a liquid aerosol of glutaraldehyde-coated CdS/Cd(OH)2 core shell quantum dots in rats.

    Science.gov (United States)

    Ma-Hock, L; Farias, P M A; Hofmann, T; Andrade, A C D S; Silva, J N; Arnaud, T M S; Wohlleben, W; Strauss, V; Treumann, S; Chaves, C R; Gröters, S; Landsiedel, R; van Ravenzwaay, B

    2014-02-10

    Quantum dots exhibit extraordinary optical and mechanical properties, and the number of their applications is increasing. In order to investigate a possible effect of coating on the inhalation toxicity of previously tested non-coated CdS/Cd(OH)2 quantum dots and translocation of these very small particles from the lungs, rats were exposed to coated quantum dots or CdCl2 aerosol (since Cd(2+) was present as impurity), 6h/d for 5 consecutive days. Cd content was determined in organs and excreta after the end of exposure and three weeks thereafter. Toxicity was determined by examination of broncho-alveolar lavage fluid and microscopic evaluation of the entire respiratory tract. There was no evidence for translocation of particles from the respiratory tract. Evidence of a minimal inflammatory process was observed by examination of broncho-alveolar lavage fluid. Microscopically, minimal to mild epithelial alteration was seen in the larynx. The effects observed with coated quantum dots, non-coated quantum dots and CdCl2 were comparable, indicating that quantum dots elicited no significant effects beyond the toxicity of the Cd(2+) ion itself. Compared to other compounds with larger particle size tested at similarly low concentrations, quantum dots caused much less pronounced toxicological effects. Therefore, the present data show that small particle sizes with corresponding high surfaces are not the only factor triggering the toxic response or translocation.

  15. Developmental toxicity of inhaled methanol in the CD-1 mouse, with quantitative dose-response modeling for estimation of benchmark doses

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.M.; Mole, M.L.; Chernoff, N.; Barbee, B.D.; Turner, C.I.

    1993-01-01

    Pregnant CD-1 mice were exposed to 1,000, 2,000, 5,000, 7,500, 10,000, or 15,000 ppm on methanol for 7 hr/day on days 6-15 of gestation. On day 17 of gestation, remaining mice were weighed, killed and the gravid uterus was removed. Numbers of implantation sites, live and dead fetuses and resorptions were counted, and fetuses were examined externally and weighed as a litter. Significant increases in the incidence of exencephaly and cleft palate were observed at 5,000 ppm and above, increased postimplantation mortality at 7,500 ppm and above (including an increasing incidence of full-litter resorption), and reduced fetal weight at 10,000 ppm and above. A dose-related increase in cervical ribs or ossification sites lateral to the seventh cervical vertebra was significant at 2,000 ppm and above. Thus, the NOAEL for the developmental toxicity in this study is 1,000 ppm. The results of this study indicate that inhaled methanol is developmentally toxic in the mouse at exposure levels which were not maternally toxic. Litters of pregnant mice gavaged orally with 4 g methanol/kg displayed developmental toxic effects similar to those seen in the 10,000 ppm methanol exposure group. (Copyright (c) 1993 Wiley-Liss, Inc.)

  16. Acute toxicity of polyethylene glycol p-isooctylphenol ether in Syrian hamsters exposed by inhalation or bronchopulmonary lavage

    Energy Technology Data Exchange (ETDEWEB)

    Damon, E.G. (Inhalation Toxicology Research Inst., Albuquerque, NM); Halliwell, W.H.; Henderson, T.R.; Mokler, B.V.; Jones, R.K.

    1982-01-01

    Dose-response studies were conducted with Syrian hamsters exposed to polyethylene glycol p-isooctylphenyl ether (Triton X-100) via inhalation or bronchopulmonary lavage. Syrian hamsters were exposed to an aerosol of Triton X-100 with a mass median aerodynamic diameter of 1.5 ..mu..m and a concentration of 3.0 mg/liter. Estimated initial lung burdens of Triton X-100 ranged from 800 to 3100 ..mu..g. Hamsters were lavaged with concentrations of Triton X-100 ranging from 0.01 to 0.10% in isotonic saline resulting in initial lung burdens of Triton X-100 that ranged from 300 to 3200 ..mu..g. The LD50/7 values were 1700 ..mu..g (1300 to 2100 ..mu..g, 95% confidence limits) for the inhalation study and 2100 (1900 to 2700) ..mu..g for the lavage study. The difference between the LD50/7 values for the two methods of exposure was not significant. However, histopathological examination revealed differences in the nature and distribution of pathologic changes observed in animals exposed by the two routes of administration. Animals exposed by inhalation died as a result of ulcerative laryngitis and laryngeal edema with only minimal pulmonary pathologic alterations. Animals exposed by lavage, where the larynx was not exposed to Triton X-100, died from pulmonary edema and acute exudative pneumonia. These results demonstrate the need for careful selection of exposure methods to meet the specific objectives of a toxicology study.

  17. Removal of toxic mercury from petroleum oil by newly synthesized molecularly-imprinted polymer.

    Science.gov (United States)

    Khairi, Nor Ain Shahera; Yusof, Nor Azah; Abdullah, Abdul Halim; Mohammad, Faruq

    2015-05-08

    In recent years, molecularly-imprinted polymers (MIPs) have attracted the attention of several researchers due to their capability for molecular recognition, easiness of preparation, stability and cost-effective production. By taking advantage of these facts, Hg(II) imprinted and non-imprinted copolymers were prepared by polymerizing mercury nitrate stock solution (or without it) with methacrylic acid (MAA), 2-hydroxyl ethyl methacrylate (HEMA), methanol and ethylene glycol dimethacrylate (EGDMA) as the monomer, co-monomer solvent (porogen) and cross-linker, respectively. Thus, the formed Hg(II) imprinted polymer was characterized by using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), Brunauer, Emmett and Teller (BET) and thermal gravimetric analysis (TGA). The separation and preconcentration characteristics of Hg(II) imprinted polymer were investigated by solid phase extraction (SPE) procedures, and an optimal pH of 7 was investigated as ideal. The specific surface area of the Hg(II) imprinted polymer was found to be 19.45 m2/g with a size range from 100 to 140 µm in diameter. The maximum adsorption capacity was observed to be 1.11 mg/g of Hg(II) imprinted beads with 87.54% removal of Hg(II) ions within the first 5 min. The results of the study therefore confirm that the Hg(II) imprinted polymer can be used multiple times without significantly losing its adsorption capacity.

  18. Removal of Toxic Mercury from Petroleum Oil by Newly Synthesized Molecularly-Imprinted Polymer

    Directory of Open Access Journals (Sweden)

    Nor Ain Shahera Khairi

    2015-05-01

    Full Text Available In recent years, molecularly-imprinted polymers (MIPs have attracted the attention of several researchers due to their capability for molecular recognition, easiness of preparation, stability and cost-effective production. By taking advantage of these facts, Hg(II imprinted and non-imprinted copolymers were prepared by polymerizing mercury nitrate stock solution (or without it with methacrylic acid (MAA, 2-hydroxyl ethyl methacrylate (HEMA, methanol and ethylene glycol dimethacrylate (EGDMA as the monomer, co-monomer solvent (porogen and cross-linker, respectively. Thus, the formed Hg(II imprinted polymer was characterized by using Fourier transform infrared spectroscopy (FTIR, field emission scanning electron microscopy (FESEM, Brunauer, Emmett and Teller (BET and thermal gravimetric analysis (TGA. The separation and preconcentration characteristics of Hg(II imprinted polymer were investigated by solid phase extraction (SPE procedures, and an optimal pH of 7 was investigated as ideal. The specific surface area of the Hg(II imprinted polymer was found to be 19.45 m2/g with a size range from 100 to 140 µm in diameter. The maximum adsorption capacity was observed to be 1.11 mg/g of Hg(II imprinted beads with 87.54% removal of Hg(II ions within the first 5 min. The results of the study therefore confirm that the Hg(II imprinted polymer can be used multiple times without significantly losing its adsorption capacity.

  19. Repeated dose oral toxicity of inorganic mercury in wistar rats: biochemical and morphological alterations

    Directory of Open Access Journals (Sweden)

    M. D. Jegoda

    2013-06-01

    Full Text Available Aim: The study was conducted to find out the possible toxic effect of mercuric chloride (HgCl2 at the histological, biochemical, and haematological levels in the wistar rats for 28 days. Materials and Methods: The biochemical and hematological alteration were estimated in four groups of rat (each group contain ten animals, which were treated with 0 (control, 2, 4, and 8 mg/kg body weight of HgCl2 through oral gavage. At the end of study all rats were sacrificed and subjected for histopathology. Result: A significantly (P < 0.05 higher level of serum alanine amino transferase (ALT, gamma Glutamyle Transferase, and creatinine were recorded in treatment groups, while the level of alkaline phosphtase (ALP was significantly decreased as compared to the control group. The toxic effect on hematoclogical parameter was characterized by significant decrease in hemoglobin, packed cell volume, total erythrocytes count, and total leukocyte count. Gross morphological changes include congestion, severe haemorrhage, necrosis, degenerative changes in kidneys, depletion of lymphocyte in spleen, decrease in concentration of mature spermatocyte, and edema in testis. It was notable that kidney was the most affected organ. Conclusion: Mercuric chloride (HgCl caused dose-dependent toxic effects on blood parameters and kidney. [Vet World 2013; 6(8.000: 563-567

  20. Pulmonary toxicity and fate of agglomerated 10 and 40 nm aluminum oxyhydroxides following 4-week inhalation exposure of rats: toxic effects are determined by agglomerated, not primary particle size.

    Science.gov (United States)

    Pauluhn, Jürgen

    2009-05-01

    Inhaled polydisperse micronsized agglomerated particulates composed of nanosized primary particles may exert their pulmonary toxicity in either form, depending on whether these tightly associated structures are disintegrated within the biological system or not. This hypothesis was tested in a rat bioassay using two calcined aluminum oxyhydroxides (AlOOH) consisting of primary particles in the range of 10-40 nm. Male Wistar rats were nose-only exposed to 0.4, 3, and 28 mg/m(3) in two 4-week (6 h/day, 5 days/week) inhalation studies followed by a 3-month postexposure period. The respective mass median aerodynamic diameter (MMAD) of agglomerated particles in inhalation chambers was 1.7 and 0.6 mum. At serial sacrifices, pulmonary toxicity was characterized by bronchoalveolar lavage (BAL) and histopathology. The retention kinetics of aluminum (Al) was determined in lung tissue, BAL cells, and selected extrapulmonary organs, including lung-associated lymph nodes (LALNs). Significant changes in BAL, lung, and LALN weights occurred at 28 mg/m(3). Histopathology revealed alveolar macrophages with enlarged and foamy appearance, increased epithelial cells, inflammatory cells, and focal septal thickening. The determination of aluminum in lung tissue shows that the cumulative lung dose was higher following exposure to AlOOH-40 nm/MMAD-0.6 mum than to AlOOH-10 nm/MMAD-1.7 mum, despite identical exposure concentrations. The associated pulmonary inflammatory response appears to be principally dependent on the agglomerated rather than primary particle size. Despite high lung burdens, conclusively increased extrapulmonary organ burdens did not occur at any exposure concentration and postexposure time point. Particle-induced pulmonary inflammation was restricted to cumulative doses exceeding approximately 1 mg AlOOH/g lung following 4-week exposure at 28 mg/m(3). It is concluded that the pulmonary toxicity of nanosized, agglomerated AlOOH particles appears to be determined by the

  1. Exposure and toxic effects of elemental mercury in gold-mining activities in Ecuador.

    Science.gov (United States)

    Harari, Raúl; Harari, Florencia; Gerhardsson, Lars; Lundh, Thomas; Skerfving, Staffan; Strömberg, Ulf; Broberg, Karin

    2012-08-13

    Traditional gold mining, using metallic mercury (Hg(0)) to form gold amalgam, followed by burning to remove the Hg(0), is widely used in South America, Africa and Asia. The gold is sold to merchants who burn it again to eliminate remaining Hg(0). In Ecuador, 200 gold miners, 37 gold merchants and 72 referents were studied. The median Hg concentrations in urine (U-Hg) were 3.3 (range 0.23-170), 37 (3.2-420), and 1.6 (0.2-13)μg/g creatinine, respectively, and in whole blood (B-Hg) were 5.2, 30, and 5.0 μg/L, respectively. Biomarker concentrations among merchants were statistically significantly higher than among miners and referents; also the miners differed from the referents. Burning of gold amalgam among miners was intermittent; U-Hg decreased in the burning-free period. In computerized neuromotor examinations, B-Hg and U-Hg concentrations were associated with increases in the centre frequency of the tremor, as well as in reaction time and postural stability.Retention of Hg (B-Hg), and the elimination rate (U-Hg) appears to be modified by polymorphism in a gene of an enzyme in the glutathione synthesis (GCLM), but there were no significant genetic modifications for the associations between exposure and neurotoxicity.Thus, the gold merchants have a much higher exposure and risk than the miners, in whom the exposure varies over time. The metabolism of Hg is modified by genetic traits. The present exposure to Hg had limited neurotoxic effects.

  2. Inhalation toxicity of Cyclosarin (GF) vapor in rats as a function of exposure concentration and duration: potency comparison to sarin (GB).

    Science.gov (United States)

    Anthony, J Steven; Haley, M; Manthei, J; Way, R; Burnett, D; Gaviola, B; Sommerville, D; Crosier, R; Mioduszewski, R; Thomson, S; Crouse, C; Matson, K

    2004-02-01

    The inhalation toxicity of cyclohexyl methylphosphonofluoridate (GF) was examined in male and female Sprague-Dawley rats exposed by whole body in a dynamic 750-L chamber. The objectives of this study were to (1) generate GF vapor in a dynamic inhalation chamber system, starting in the lethal to near-lethal concentration range, (2) examine dose-response effects of inhaled GF vapor and analyze the relationship between concentration (C) and exposure duration (T) in determining probability of lethality, and (3) establish a lethal potency ratio between GF and the more volatile agent Sarin (GB). Using a syringe pump, GF vapor concentrations were generated for exposure times of 10, 60, and 240 min. Dose-response curves with associated slopes were determined for each exposure duration by the Bliss probit method. GF vapor exposures were associated with sublethal clinical signs such as tremors, convulsions, salivation, and miosis. Concentration-exposure time values for lethality in 50% of the exposed population (LCT(50)) were calculated for 24-h and 14-day postexposure periods for 10-, 60-, and 240-min exposures. In general, LCT(50) values were lower in female rats than males and increased with exposure duration; that is, CT was not constant over time. The GF LCT(50) values for female rats were 253 mg min/m(3) at 10 min, 334 mg min/m(3) at 60 min, and 533 mg min/m(3) at 240 min, while the values for males were 371, 396, and 585 mg min/m(3), respectively. The GB LCT(50) values for female rats were 235 mg min/m(3) at 10 min, 355 mg min/m(3) at 60 min, and 840 mg min/m(3) at 240 min, while the values for males were 316, 433, and 1296 mg min/m(3), respectively. At longer exposure durations, the LCT(50) for GF was less than that found for GB but at shorter exposure durations, the LCT(50) for GF was more than that found for GB. Empirical models, consisting of the toxic load model plus higher order terms, were developed and successfully fit to the data.

  3. Mechanisms of mercury bioremediation.

    Science.gov (United States)

    Essa, A M M; Macaskie, L E; Brown, N L

    2002-08-01

    Mercury is one of the most toxic heavy metals, and has significant industrial and agricultural uses. These uses have led to severe localized mercury pollution. Mercury volatilization after its reduction to the metallic form by mercury-resistant bacteria has been reported as a mechanism for mercury bioremediation [Brunke, Deckwer, Frischmuth, Horn, Lunsdorf, Rhode, Rohricht, Timmis and Weppen (1993) FEMS Microbiol. Rev. 11, 145-152; von Canstein, Timmis, Deckwer and Wagner-Dobler (1999) Appl. Environ. Microbiol. 65, 5279-5284]. The reduction/volatilization system requires to be studied further, in order to eliminate the escape of the metallic mercury into the environment. Recently we have demonstrated three different mechanisms for mercury detoxification in one organism, Klebsiella pneumoniae M426, which may increase the capture efficiency of mercury.

  4. Got Mercury?

    Science.gov (United States)

    Meyers, Valerie; James, John T.; McCoy, Torin; Garcia, Hector

    2010-01-01

    Many lamps used in various spacecraft contain elemental mercury, which is efficiently absorbed through the lungs as a vapor. The liquid metal vaporizes slowly at room temperature, but may be completely vaporized when lamps are operating. Because current spacecraft environmental control systems are unable to remove mercury vapors, we considered short-term and long-term exposures. Using an existing study, we estimated mercury vapor releases from lamps that are not in operation during missions lasting less than or equal to 30 days; whereas we conservatively assumed complete vaporization from lamps that are operating or being used during missions lasing more than 30 days. Based on mercury toxicity, the Johnson Space Center's Toxicology Group recommends stringent safety controls and verifications for any hardware containing elemental mercury that could yield airborne mercury vapor concentrations greater than 0.1 mg/m3 in the total spacecraft atmosphere for exposures lasting less than or equal to 30 days, or concentrations greater than 0.01 mg/m3 for exposures lasting more than 30 days.

  5. Toxicity of heavy metals: 1. Correlation of metal toxicity with in vitro calmodulin inhibition. 2. Interactions of inorganic mercury with red blood cells: Control vs. amyotrophic lateral sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Henson, J.L.C.

    1989-01-01

    The toxic effects of metals are examined in two separate in vitro systems. In the first system, the correlation between published mouse LD{sub 50} values and experimentally derived values for calmodulin inhibition was determined. Calmodulin activity was defined as stimulated phosphodiesterase (PDE) activity. The basal PDE activity was determined with each cation and was unaffected by any of the concentrations utilized. The IC{sub 50} was determined from a plot of the log of the cation concentration vs. stimulated PDE activity for each cation. A very strong correlation was obtained when the IC{sub 50} vs. mouse LD{sub 50} curve was examined (p < 0.001). Calmodulin regulates many enzyme systems and processes that affect or are affected by calcium. This study was examined in light of the possible role of calcium in cell damage and death. In the second study, the interactions of erythrocytes (RBCs) and inorganic mercury (Hg) were examined. A broad range of Hg concentrations were utilized to explore the nature of the interactions. Two different mechanisms of RBC Hg accumulation and retention were evident. At lower Hg concentrations (0.001-0.1 {mu}M), the RBC accumulation/retention of Hg was constant (52% of available Hg), reversible, and temperature sensitive. At higher concentrations (1-100 {mu}M), the accumulation increased with Hg concentration, was not reversible, and was not temperature sensitive. A relationship between Hg and amyotrophic lateral sclerosis (ALS) is suggested by several reports in the literature. The accumulation/ retention of Hg by RBCs from control and ALS patients were compared. The RBCs from ALS patients released far more Hg during a two hr incubation 37C at 10 and 100 {mu}M Hg compared to controls.

  6. Assessment of the reproductive toxicity of inhalation exposure to ethyl tertiary butyl ether in male mice with normal, low active and inactive ALDH2.

    Science.gov (United States)

    Weng, Zuquan; Ohtani, Katsumi; Suda, Megumi; Yanagiba, Yukie; Kawamoto, Toshihiro; Nakajima, Tamie; Wang, Rui-Sheng

    2014-04-01

    No data are available regarding aldehyde dehydrogenase 2 (ALDH2) polymorphisms related to the reproductive toxicity possibly caused by ethyl tertiary butyl ether (ETBE). In this study, two inhalation experiments were performed in Aldh2 knockout (KO), heterogeneous (HT) and wild type (WT) C57BL/6 male mice exposed to ETBE, and the data about general toxicity, testicular histopathology, sperm head numbers, sperm motility and sperm DNA damage were collected. The results showed that the 13-week exposure to 0, 500, 1,750 and 5,000 ppm ETBE significantly decreased sperm motility and increased levels of sperm DNA strand breaks and 8-hydroxy-deoxyguanosine in both WT and KO mice, the effects were found in 1,750 and 5,000 ppm groups of WT mice, and all of the three exposed groups of KO mice compared to the corresponding control; furthermore, ETBE also caused decrease in the relative weights of testes and epididymides, the slight atrophy of seminiferous tubules of testis and reduction in sperm numbers of KO mice exposed to ≥500 ppm. In the experiment of exposure to lower concentrations of ETBE (0, 50, 200 and 500 ppm) for 9 weeks, the remarkable effects of ETBE on sperm head numbers, sperm motility and sperm DNA damage were further observed in KO and HT mice exposed to 200 ppm ETBE, but not in WT mice. Our findings suggested that only exposure to high concentrations of ETBE might result in reproductive toxicity in mice with normal active ALDH2, while low active and inactive ALDH2 enzyme significantly enhanced the ETBE-induced reproductive toxicity in mice, even exposed to low concentrations of ETBE, mainly due to the accumulation of acetaldehyde as a primary metabolite of ETBE.

  7. Toxicity of selenium (Na sub 2 SeO sub 3 ) and mercury (HgCl sub 2 ) on the planarian Dugesia gonocephala

    Energy Technology Data Exchange (ETDEWEB)

    Congiu, A.M.; Casu, S.; Ugazio, G. (Istituto di Genetica (Italy))

    1989-10-01

    The toxicity of selenium (Na{sub 2}SeO{sub 3}) and mercury (HgCl{sub 2}) was determined by using a freshwater planarian which is particularly sensitive to pollution, and belongs to a fissiparous breed of Dugesia gonocephala. The mortality and fissiparity frequency of the subjects were studied. They were exposed to intense treatments (48 hours) or for medium to long periods of time (21 days) to either the single compounds or a combination of both, and were fed or fasting. The lethal effect of sodium selenite is correlated to the food intake, whereas the toxicity of mercurous chloride is probably the result of a fixative effect which does not depend on feeding. The 21-day treatment with the first compound has a non-negligible lethal effect which is probably due to an accumulation phenomenon. At doses where an antioxidant effect prevails, fissiparity is stimulated. On the other hand, the second compound reduces reproduction frequency to half the base values. Compared to the Paracentrotus lividus, the Dugesia gonocephala offers various advantages concerning toxicological experiments; besides being easier to handle in the laboratory, it is available all year round and is not subject to seasonal cycles. It is also more susceptible to the toxic effect of mercury, which is a common and highly toxic pollutant, than the sea urchin.

  8. Mercury Toxicity and Contamination of Households from the Use of Skin Creams Adulterated with Mercurous Chloride (Calomel).

    Science.gov (United States)

    Copan, Lori; Fowles, Jeff; Barreau, Tracy; McGee, Nancy

    2015-09-02

    Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users' homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m³ of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m³. Mercury contamination of cream users' homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment.

  9. Mercury Toxicity and Contamination of Households from the Use of Skin Creams Adulterated with Mercurous Chloride (Calomel

    Directory of Open Access Journals (Sweden)

    Lori Copan

    2015-09-01

    Full Text Available Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users’ homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m3 of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m3. Mercury contamination of cream users’ homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment.

  10. Mercury Toxicity and Contamination of Households from the Use of Skin Creams Adulterated with Mercurous Chloride (Calomel)

    Science.gov (United States)

    Copan, Lori; Fowles, Jeff; Barreau, Tracy; McGee, Nancy

    2015-01-01

    Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users’ homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m3 of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m3. Mercury contamination of cream users’ homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment. PMID:26364641

  11. Acute inhalation toxicity evaluation of a 93:7 mixture of perfluoro-2-butene and 1-bromopropane, a replacement candidate for ozone depleting substances. Interim report, July--August 1997

    Energy Technology Data Exchange (ETDEWEB)

    Feldmann, M.L.; Leahy, H.F.; Vinegar, A.

    1997-10-01

    The DoD requires the development of toxicity profiles for chemical substitute candidates proposed to replace ozone depleting substances such as chloro- and fluorocarbons and halons. A 93:7 mixture of perfluoro-2-butene and 1-bromopropane was identified as a possible replacement candidate for ozone-depleting fire extinguishants. An acute inhalation toxicity test utilizing male and female Fischer 344 rats was performed on this test material. No deaths occurred in any of the rats exposed to 5.3 mg/L of the 93:7 perfluoro-2-butene and 1-bromopropane mixture. Body weights of male and female rats during the subsequent 14-day observation period were unaffected by treatment. The test material did not produce acute toxicity via the inhalation route.

  12. Update to agency for toxic substances and disease registry 2012 report on assessment of biota exposure to mercury originating from Savannah River Site.

    Energy Technology Data Exchange (ETDEWEB)

    Kuhne, W. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-08-10

    The purpose of this report is to 1) update previous Savannah River National Laboratory (SRNL) assessment reports (Kvartek et al. 1994 and Halverson et al. 2008) on the fate of mercury in the Savannah River Site (SRS) environment and 2) address comments and recommendations from the review of SRS by the Agency for Toxic Substances and Disease Registry (ATSDR) concerning the evaluation of exposures to contaminants in biota originating from the SRS. The ATSDR reviewed and evaluated data from SRS, South Carolina Department of Health & Environmental Control (SCDHEC) and the Georgia Department of Natural Resources (GDNR) concerning the non-radioactive contaminant mercury. This report will provide a response and update to conclusions and recommendations made by the ATSDR.

  13. Pulmonary toxicity of inhaled nanoscale and fine zinc oxide particles: mass and surface area as an exposure metric.

    Science.gov (United States)

    Ho, Meng; Wu, Kuen-Yuh; Chein, Hung-Min; Chen, Lung-Chi; Cheng, Tsun-Jen

    2011-12-01

    The total surface area is known to be an effective exposure metric for predicting the lung toxicity of low solubility nanoparticles (NPs). However, if NPs are dissolved quickly enough in the lungs, the mass may be correlated with the toxicity. Recent studies have found that the toxicity of zinc oxide (ZnO) NPs was caused by the release of zinc ions. Thus, we hypothesized that mass could be used as an exposure metric for the toxicity of ZnO NPs. Healthy Sprague-Dawley rats were exposed to a low, moderate, or high dose of 35 and 250 nm ZnO particles or filtered air. Bronchoalveolar lavage fluid was collected to determine lung inflammation, injury and oxidative stress. The lung inflammation induced by ZnO particles according to different concentration metrics, including number, mass and surface area, was compared. The mass concentration was significantly correlated with the percentage of neutrophils (R(2) = 0.84), number of neutrophils (R(2) = 0.84) and total cells (R(2) = 0.73). Similarly, surface area concentration was significantly correlated with the percentage of neutrophils (R(2) = 0.94), number of neutrophils (R(2) = 0.81) and total cells (R(2) = 0.76). There was no correlation between the number and lung inflammation. We found that both mass and surface area were effective as metrics for the toxicity of ZnO NPs, although only surface area was previously indicated to be an effective metric. Our results are also consistent with recent study results that ZnO NPs and released zinc ions may play a role mediating the toxicity of NPs.

  14. Attempts to quantitate the protective effect of selenium against mercury toxicity using Japanese quail

    Energy Technology Data Exchange (ETDEWEB)

    El-Begearmi, M.M.; Goudie, C.; Ganther, H.E.; Sunde, M.L.

    1973-01-01

    A previous report (Science, Vol. 175, pp. 1122-4) showed that 17% dry tuna containing high levels of Se offered some protection to Japanese quail against methylmercury toxicity. Sodium selenite also protected rats fed methyl Hg in the water. In two experiments, graded levels of Se from 0.35 to 6.0 ppm (total Se in diet) were fed to Japanese quail along with 20.0 ppm of methylmercury. In the first experiment there were no survivors with 20 ppm methylmercury at 67 days. When 0.35, 0.70, 1.5 and 3.0 ppm Se were provided, the survival rates were 4%, 19%, 26% and 33% respectively. In the second experiment, 3% survived to 67 days (with 20 ppm Hg). When 0.35, 0.70, 1.5, 3.0 and 6.0 ppm Se were provided the survival rates were 21%, 36%, 64%, 64%, and 73% respectively. The addition of 6.0 ppm Se to the diet did not effect mortality (100% survival at 67 days) body weight or egg production; however it reduced hatchability. The quail fed the control diet (no added Hg or Se) survived at an average rate of 85%. The data show that 1.5-6.0 ppm of Se increased survival times considerably for quail fed 20 ppm CH/sub 3/Hg from one day of age to 67 days. Eventually nearly all quail die with this level of Hg (20 ppm).

  15. Identification of the appropriate dose metric for pulmonary inflammation of silver nanoparticles in an inhalation toxicity study

    NARCIS (Netherlands)

    Braakhuis, Hedwig M; Cassee, Flemming R; Fokkens, Paul H B; de la Fonteyne, Liset J J; Oomen, Agnes G; Krystek, Petra; de Jong, Wim H; van Loveren, Henk; Park, Margriet V D Z

    2016-01-01

    Abstract A number of studies have shown that induction of pulmonary toxicity by nanoparticles of the same chemical composition depends on particle size, which is likely in part due to differences in lung deposition. Particle size mostly determines whether nanoparticles reach the alveoli, and where

  16. Modeling Mercury in Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jeremy C [ORNL; Parks, Jerry M [ORNL

    2016-01-01

    Mercury (Hg) is a naturally occurring element that is released into the biosphere both by natural processes and anthropogenic activities. Although its reduced, elemental form Hg(0) is relatively non-toxic, other forms such as Hg2+ and, in particular, its methylated form, methylmercury, are toxic, with deleterious effects on both ecosystems and humans. Microorganisms play important roles in the transformation of mercury in the environment. Inorganic Hg2+ can be methylated by certain bacteria and archaea to form methylmercury. Conversely, bacteria also demethylate methylmercury and reduce Hg2+ to relatively inert Hg(0). Transformations and toxicity occur as a result of mercury interacting with various proteins. Clearly, then, understanding the toxic effects of mercury and its cycling in the environment requires characterization of these interactions. Computational approaches are ideally suited to studies of mercury in proteins because they can provide a detailed picture and circumvent issues associated with toxicity. Here we describe computational methods for investigating and characterizing how mercury binds to proteins, how inter- and intra-protein transfer of mercury is orchestrated in biological systems, and how chemical reactions in proteins transform the metal. We describe quantum chemical analyses of aqueous Hg(II), which reveal critical factors that determine ligand binding propensities. We then provide a perspective on how we used chemical reasoning to discover how microorganisms methylate mercury. We also highlight our combined computational and experimental studies of the proteins and enzymes of the mer operon, a suite of genes that confers mercury resistance in many bacteria. Lastly, we place work on mercury in proteins in the context of what is needed for a comprehensive multi-scale model of environmental mercury cycling.

  17. Response of DNA, proteins, lipids and antioxidant enzymes as measure of toxicity to mercury exposures in green mussel Perna viridis

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.; Jena, K.B.; Chainy, G.B.N.

    Studies on exposures of gills of green-lipped mussel Perna viridis to sublethal levels of mercury (Hg) indicates that oxidative stress marker like lipids peroxidation and protein carbonyl content increase. With the exception of superoxide dismutase...

  18. Progress in treatment and study of renal toxicity by mercury poisoning%汞的肾毒性及治疗研究进展

    Institute of Scientific and Technical Information of China (English)

    陈子安; 聂志勇; 李万华; 胡鹏遥; 隋昕; 邱泽武; 王永安

    2016-01-01

    Mercury is one of the common heavy-metal toxins,which can cause damage throughout the body in a variety of ways. Cases of renal toxicity of mercury poisoning are increasing clinically. However,little is known about nephrotoxicity mechanisms,and treatment remains unsatisfactory. The mechanism of mercury toxic nephropathy is reviewed in this paper,including the direct toxic effect on the kidney,the injury to the biomembrane system,generation of Hg-metallothionein,imbalance of intra⁃cellular calciumion,oxidative damage,induced apoptosis,and immune injury. Besides,the mechanism and limitation of common therapies,potential developments of the field are discussed. This review will facilitate further investigations therapies about both the mechanism and treatment of mercury toxic nephropathy.%汞是常见的重金属毒物,多种原因导致的急慢性汞中毒可对人体多个脏器产生严重损害。临床上因汞中毒导致的肾病逐年增多,其损伤机制尚不明确,治疗手段有限。本文就汞的肾毒性作用机制研究进展进行综述,包括汞对肾的直接毒性作用,生物膜系统受损,汞-金属硫蛋白复合物形成,胞内Ca2+平衡失调,氧化损伤,诱导细胞凋亡,免疫性损伤等。归纳总结了临床上常见治疗方法的机理及局限,并对几种当前研究的热点问题和发展方向进行了介绍,在此基础之上探究汞对肾造成损害的疾病模型,旨在为临床上慢性汞中毒导致的肾病的治疗方法提供相关支持。

  19. Chronic Mercury Intoxication Masquerading as Systemic Disease: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Alexandre Malek

    2017-05-01

    Full Text Available Background: Mercury is a highly toxic environmental metal that exists in three different forms: elemental, inorganic and organic. Intoxication occurs in either occupational or non-occupational settings, mainly after the inhalation of vapour and fumes in work places, laboratories or homes. Chronic mercury toxicity ranges from mild and insignificant to severe and life-threatening. We describe the case of a young male patient who presented with multiple organ dysfunction after chronic mercury exposure. Case presentation: We report the case of 28-year-old male artisanal gold miner who was admitted to hospital for severe neurological impairment associated with inflammatory bowel disease-like symptoms and a skin rash after mercury exposure. Symptomatic treatment and corticosteroid administration assured rapid clinical improvement. Chronic mercury poisoning can masquerade as an autoimmune or systemic inflammatory disease. Conclusion: Physicians should be aware that low exposure to mercury, even from artisanal gold mining, may be harmful to health. Management can be simple without the need for aggressive or invasive therapeutic measures. Larger case series are required in order to establish a clear management plan.

  20. Municipal actions to reduce mercury

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-03-15

    This paper presented proper management practices for products containing mercury. The measures can help reduce mercury releases, occupational exposure and mercury spills, thereby preventing impacts on human health and the environment. Despite mercury's toxic nature, many common products that contain mercury are commercially available. These include thermostats, thermometers, fluorescent lamps, pressure measuring devices, electrical switches and relays, and dental amalgam. Mercury emissions are also associated with base metal smelting, waste incineration and coal-fired power generation. Mercury in the environment is a global issue, because it can travel in the atmosphere on wind currents. The actions taken by municipalities to address the issue include reducing or eliminating mercury releases from internal municipal operations and sources within the community. This document provided guidance on how to develop a Municipal Mercury Elimination Policy and Plan that will help reduce mercury releases. It presented information and case studies that will help municipalities manage mercury-containing products found in municipal buildings and street lighting. Information on sources of mercury from within the community was presented along with case studies that can help municipalities determine where community action is needed to reduce mercury releases. The 5 modules of this document were intended to help municipalities identify priorities, timelines and budget requirements for mercury initiatives. It was emphasized that municipalities that adopt a Municipal Mercury Elimination Policy and Plan formally commit to reducing and eliminating mercury from the environment. tabs., figs.

  1. 氟氯氰菊酯亚急性吸入毒性实验研究%Inhalation toxicity of cyfluthrin for 28-day repeated dose in rats

    Institute of Scientific and Technical Information of China (English)

    秦珩; 乔善磊; 顾军; 钟义红; 杨洪宝; 王玉邦; 施爱民

    2012-01-01

    Objective To determine the inhalation toxicity and find the non -observed adverse effect level (NOAEL) of cyfluthrin for a 28-day repeated dose in rats. Methods Clean-grade SD rats were randomly divided into 5 groups with 5 females and 5 males in each. The animals inhaled DMSO or cyfluthrin at the concentration of 0, 7. 81 , 9. 05 and 18. 98 mg/m for 4 weeks (6 h/d, 5 d/w). At the end of inhalation , all the animals were kindly sacrificed. Their organs were collected for histopathological examination . Blood samples were collected for analysis of complete blood count , biochemistry and coagulation. Results The animals in 18. 98 mg/m3 group were found scratching repeatedly around the mouth, listless, fidgeting, trembling, discharging blood around the mouth and nose . However, symptoms in females were less serious than in males. Furthermore , the body mass , feed efficiency , weight of kidney of animals in this dose male group were found decreased compared with the control group . Biochemistry detection revealed that serum AST was elevated markedly in both genders of 18. 98 mg/m3 group and in males of 9. 05 mg/m3 group. No obvious abnormity was found in 7.81 mg/m3 group or control group. Conclusion Based on the results above, the non-observed adverse effect level (NOAEL) of cyfluthrin in SD rats is 7. 81 mg/m3 for 28 d repeated inhalation in this study.%目的 观察氟氯氰菊酯染毒大鼠亚急性吸入毒性.方法 7周龄清洁级SD大鼠随机分成5组,每组雌雄各5只,分别吸入氟氯氰菊酯0,7.81,9.05,18.98 mg/m3及溶剂二甲亚砜,每天6 h,每周5 d,共28 d.实验结束时取血液做常规生化指标、血细胞指标、血凝学指标检测.取心、肝、脾等8种主要脏器称重并做病理组织学检查.结果 18.98 mg/m3组动物在染毒中呈现反复抓挠口周、烦躁不安、鼻有血性分泌物、颤抖,染毒结束后呈现萎靡、蜂腰、四肢无力的体征.雌性动物的毒性表现较雄性低.与溶剂对照组相

  2. Environmental and human exposure assessment monitoring of communities near an abandoned mercury mine in the Philippines: a toxic legacy.

    Science.gov (United States)

    Maramba, Nelia P C; Reyes, Jose Paciano; Francisco-Rivera, Ana Trinidad; Panganiban, Lynn Crisanta R; Dioquino, Carissa; Dando, Nerissa; Timbang, Rene; Akagi, Hirokatsu; Castillo, Ma Teresa; Quitoriano, Carmela; Afuang, Maredith; Matsuyama, Akito; Eguchi, Tomomi; Fuchigami, Youko

    2006-10-01

    Abandoned mines are an important global concern and continue to pose real or potential threats to human safety and health including environmental damage/s. Very few countries had government mine regulation and reclamation policies until the latter part of the century where legal, financial and technical procedures were required for existing mining operations. Major reasons for mine closure may be mainly due to poor economies of the commodity making mining unprofitable, technical difficulties and national security. If the mine is abandoned, more often than not it is the government that shoulders the burden of clean-up, monitoring and remediation. The topic of abandoned mines is complex because of the associated financial and legal liability implications. Abandoned mercury mines have been identified as one of the major concerns because of their significant long-term environmental problems. Primary mercury production is still ongoing in Spain, Kyrgzystan, China, Algeria, Russia and Slovakia while world production declined substantially in the late 1980s. In the Philippines, the mercury mine located southeast of Manila was in operation from 1955 to 1976, before ceasing operation because of the decline in world market price for the commodity. During this time, annual production of mercury was estimated to be about 140,000 kg of mercury yearly. Approximately 2,000,000 t of mine-waste calcines (retorted ore) were produced during mining and roughly 1,000,000 t of these calcines were dumped into nearby Honda Bay to construct a jetty to facilitate mine operations where about 2000 people reside in the nearby three barangays. In October, 1994 the Department of Health received a request from the Provincial Health Office for technical assistance relative to the investigation of increasing complaints of unusual symptoms (e.g. miscarriages, tooth loss, muscle weakness, paralysis, anemia, tremors, etc.) among residents of three barangays. Initial health reports revealed significant

  3. A CHRONIC INHALATION STUDY OF METHYL BROMIDE TOXICITY IN B6C3F1 MICE. (FINAL REPORT TO THE NATIONAL TOXICOLOGY PROGRAM)

    Energy Technology Data Exchange (ETDEWEB)

    HABER, S.B.

    1987-06-26

    This report provides a detailed account of a two year chronic inhalation study of methyl bromide toxicity in B6C3Fl mice conducted for the National Toxicology Program. Mice were randomized into three dose groups (10, 33 and 100 ppm methyl bromide) and one control group (0 ppm) per sex and exposed 5 days/week, 6 hours/day, for a total of 103 weeks. Endpoints included body weight; clinical signs and mortality, and at 6, 15 and 24 months of exposure, animals were sacrificed for organ weights, hematology and histopathology. In addition, a subgroup of animals in each dosage group was monitored for neurobehavioral and neuropathological changes. After only 20 weeks of exposure, 48% of the males and 12% of the females in the 100 ppm group had died. Exposures were terminated in that group and the surviving mice were observed for the duration of the study. Exposure of B6C3Fl mice to methyl bromide, even for only 20 weeks, produced significant changes in growth rate, mortality, organ weights and neurobehavioral functioning. These changes occurred in both males and females, but were more pronounced in males.

  4. Environmental consequences of the inhibition in the hatching of pupae of Aedes aegypti by mercury, zinc, and chromium - the abnormal toxicity of zinc

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, S.A.; Nipaney, P.C.; Soni, R.

    1985-01-01

    In continuation of our studies on the toxicity of heavy metals the authors report the impact of mercury (II), zinc (II), and chromium (VI) on hatching of the pupae of mosquito Aedes aegypti. The studies were carried out in terms of abnormal responses in swimming and flying, incompleteness of the metamorphosis and mortality - all with respect to controls. The toxicity trend with respect to the mortality of pupae in partially or completely hatched conditions, as also with respect to reduction in the number of pupae reaching the mosquito stage was Hg > Zn approx. = Cr. A comparison of lethal doze values of the metals obtained through present experiments with the levels allowable in irrigation waters, indicate that the permissible levels of zinc and chromium are higher by several orders of magnitude than the lowest lethal concentrations for pupae of A. aegypti. The studies thus point to a need for the revision of the existing standards.

  5. Melanomacrophage centers in kidney, spleen and liver: A toxic response in carp fish (Cyprinus carpio) exposed to mercury chloride

    Science.gov (United States)

    Tjahjaningsih, Wahju; Pursetyo, Kustiawan Tri; Sulmartiwi, Laksmi

    2017-02-01

    This study aims to determine the potential of melanomacrophage centers (MMCs) as a bioindicators of environment polluted with mercury chloride. This study used the carp fish that were kept in an environment that contained mercury chloride with a concentration of 0.01, 0.05 and 0.1 ppm for 21 days. The rate of accumulation of macrophages in the tissue of kidney, spleen and liver were measured by the activity of N-acetylglucosaminidase. The results showed that the MMCs in the spleen and liver tissue of the carp fish potential as the bio-indicators of polluted environment ≥0.1 ppm of mercury chloride. The increased in accumulation of macrophages found in the kidney tissue of carp fish exposed to mercury chloride concentration of 0.01, 0.05 and 0.1 ppm, although no significant difference with control (0 ppm). The suppressive effect of the accumulation of immune response showed at the carp fish liver tissue macrophages which were exposed to mercury chloride lower than carp fish that were not exposed.

  6. Mercury poisoning: an unusual cause of polyarthritis.

    Science.gov (United States)

    Karataş, G K; Tosun, A K; Karacehennem, E; Sepici, V

    2002-02-01

    Mercury is a toxic metal that is widely used in everyday life. It has organic and inorganic forms that are both toxic. As acute mercury poisoning is uncommon, diagnosis is difficult if the exposure is not manifest. It has usually a slow onset and non-specific symptoms. In this paper we report a patient who developed polyarthritis after mercury exposure.

  7. Relationship of mercury to cognitive, affective and perceptual motor functioning in a normal sample in Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    Sine, L.F.

    1983-01-01

    Although the effects of toxic levels of mercury have been well documented, the effects of subclinical levels of mercury on normal populations have generally not been studied. The purpose of this investigation was to assess the impact of mercury risk factors on cognition, affect, psychopathology, and known mercury-related symptoms in a normal sample in Hawaii exposed to subclinical although elevated levels of elemental mercury through inhalation associated with volcanic activity and of methylmercury mostly through ingestion of large ocean species fish. The following summarizes the findings and conclusions of the study: 1) a four week test-retest reliability using 41 of the subjects showed that the 41 measures used in the study exhibited an average correlation of .78. Using all 413 subjects, the average internal consistency measured by Cronbach's ..cap alpha.. was .82 for the 17 affect, psychopathology, and symptom measures; 2) nine mercury source variables were used to predict the amount of total mercury in hair. Interestingly, none of the source variables predicted hair total mercury; 3) the source variables in addition to hair total mercury and statistical control variables were used to predict the twenty-two functioning variables in the four domains cited above with a relative absence of relationships noted. This finding indicates that the normal population in Hawaii appears not to be at risk; and 4) one historical mercury source variable, reported fish intake when young, related to six functioning variables - the psychopathology measures of Somatization, Obsessive-Compulsive and Anxiety as well as the Sensory, Affect and Mental symptoms - with Beta weights in the .15 to .20 range. The implications of the findings were discussed and suggestions offered for future research especially with respect to specific high risk subgroups.

  8. Inhaler technique

    DEFF Research Database (Denmark)

    Levy, M L; Dekhuijzen, P R N; Barnes, P J

    2016-01-01

    of this process: the use of inhalers is bewildering enough, particularly with regular introduction of new drugs, devices and ancillary equipment, without unnecessary and pointless adages. We review the evidence, or lack thereof, underlying ten items of inhaler 'lore' commonly passed on by health professionals...

  9. Effect of activity state upon the production of lethalities due to the inhalation of the toxic pyrolysis products of polyacrylonitrile

    Energy Technology Data Exchange (ETDEWEB)

    Moore, S.J.; Whitney, S.; Purser, C.; Hume, A.S.

    1987-02-01

    Hydrogen cyanide is known to be produced upon the pyrolysis of the synthetic material polyacrylonitrile. Cyanide inhibits phosphorylation reactions, therefore, decreasing the amount of high energy bonds available for metabolic use. Since the energy requirements, as well as the respiratory minute volume, for an individual decrease with decreasing activity, it was of interest to investigate whether diminished physical activity would decrease the lethal potential of the pyrolysis products of polyacrylonitrile. In order to produce wide variations in physical activity, male ICR mice were pretreated with either 8.6 mg/kg dextroamphetamine sulfate ip 30 min prior to challenge, 75 mg/kg sodium pentobarbital ip 15 min prior to challenge, or 10 ml/kg of 70 proof ethyl alcohol ip 15 min prior to challenge. Control animals received injections of 10 ml/kg normal saline ip 15 min prior to challenge. Animals were subsequently challenged with the cooled/filtered smoke from the pyrolysis of polyacrylonitrile fibers at 660 C. Increased physical activity decreased the exposure time necessary to produce death. Animals pretreated with amphetamine appear to die more rapidly than control animals due to an increase in respiratory minute volume. Animals pretreated with sodium pentobarbital or ethanol appear to survive through long periods of exposure to the toxic gases due to both a decrease in minute volume and a decrease in energy utilization.

  10. Systematic review and meta-analysis links autism and toxic metals and highlights the impact of country development status: Higher blood and erythrocyte levels for mercury and lead, and higher hair antimony, cadmium, lead, and mercury.

    Science.gov (United States)

    Saghazadeh, Amene; Rezaei, Nima

    2017-10-03

    Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder that affects cognitive and higher cognitive functions. Increasing prevalence of ASD and high rates of related comorbidities has caused serious health loss and placed an onerous burden on the supporting families, caregivers, and health care services. Heavy metals are among environmental factors that may contribute to ASD. However, due to inconsistencies across studies, it is still hard to explain the association between ASD and toxic metals. Therefore the objective of this study was to investigate the difference in heavy metal measures between patients with ASD and control subjects. We included observational studies that measured levels of toxic metals (antimony, arsenic, cadmium, lead, manganese, mercury, nickel, silver, and thallium) in different specimens (whole blood, plasma, serum, red cells, hair and urine) for patients with ASD and for controls. The main electronic medical database (PubMed and Scopus) were searched from inception through October 2016. 52 studies were eligible to be included in the present systematic review, of which 48 studies were included in the meta-analyses. The hair concentrations of antimony (standardized mean difference (SMD)=0.24; 95% confidence interval (CI): 0.03 to 0.45) and lead (SMD=0.60; 95% confidence interval (CI): 0.17 to 1.03) in ASD patients were significantly higher than those of control subjects. ASD patients had higher erythrocyte levels of lead (SMD=1.55, CI: 0.2 to 2.89) and mercury (SMD=1.56, CI: 0.42 to 2.70). There were significantly higher blood lead levels in ASD patients (SMD=0.43, CI: 0.02 to 0.85). Sensitivity analyses showed that ASD patients in developed but not in developing countries have lower hair concentrations of cadmium (SMD=-0.29, CI: -0.46 to -0.12). Also, such analyses indicated that ASD patients in developing but not in developed lands have higher hair concentrations of lead (SMD=1.58, CI: 0.80 to 2.36) and mercury (SMD=0

  11. Mercury Exposure and Heart Diseases.

    Science.gov (United States)

    Genchi, Giuseppe; Sinicropi, Maria Stefania; Carocci, Alessia; Lauria, Graziantonio; Catalano, Alessia

    2017-01-12

    Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.

  12. Mercury Exposure and Heart Diseases

    Science.gov (United States)

    Genchi, Giuseppe; Sinicropi, Maria Stefania; Carocci, Alessia; Lauria, Graziantonio; Catalano, Alessia

    2017-01-01

    Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system. PMID:28085104

  13. Mercury Exposure and Heart Diseases

    Directory of Open Access Journals (Sweden)

    Giuseppe Genchi

    2017-01-01

    Full Text Available Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.

  14. Mercury-Containing Devices and Demolition

    Science.gov (United States)

    Some items inside residential buildings contain mercury, which poses a persistent and toxic human health and environmental threat. These materials should be carefully salvaged for proper recycling to prevent mercury contamination prior to demolition.

  15. Delayed acute toxicity of 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD), after oral administration, Obeys Haber's rule of inhalation toxicology.

    Science.gov (United States)

    Rozman, K K

    1999-05-01

    Eight different doses (2.5 to 10.0 mg/kg) of 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) were administered acutely to a total of 272 female Sprague-Dawley rats. The doses ranged from a NOAEL for wasting/hemorrhage to supralethal doses. Dose- and time-responses of wasting/hemorrhage, anemia, and cancer were and are being studied as end points of toxicity. The experiments will be continued until the last rat dies. There was a very steep dose- and time-response between the LOAEL for wasting/hemorrhage (2.8 mg/kg) and the third highest dose (4.1 mg/kg) of HpCDD. The dose-and time-responses were nearly symmetrical, obeying Haber's Rule of inhalation toxicology (c x t = constant) even beyond 100% mortality. Introduction of a minimum of 25% body weight loss as a discriminatory criterion to separate wasting from hemorrhage as the primary cause of death reduced variability from 5.8 to 3.2%. An arithmetic plot of the dose and time data resulted in a nearly perfect hyperbola. A logarithmic plot of these data yielded a straight line of similar perfection. Dose-response data at constant times illustrate the shifting of the dose-response curve towards a liminal value, which represents the necessary observation period for this effect. Time-response data at constant doses demonstrate the shifting of the time-response curve towards a liminal value, which represents the LOAEL for the dose-response of this effect. A three-dimensional plot of dose- and time-response data depicts the surface area on which c x t is constant along hyperbolas, in terms of wasting as the end point of toxicity. Surviving rats in all groups started developing anemia 126 days after dosing, but no rat died of wasting/hemorrhage after day 74. Rats surviving anemia began to die of lung cancer as of day 397 after dosing. Thus, although the experiment has been completed as far as dose- and time-responses of wasting/hemorrhage are concerned, it will be about another 2 years before complete dose and time

  16. Mercury exposure in a low-income community in South Africa

    CSIR Research Space (South Africa)

    Oosthuizen, MA

    2010-01-01

    Full Text Available of mercury called methylmercury, which accumulates in the food chain. Methylation of inorganic mercury in the environment into organic mercury occurs in the presence of sulphate-reducing bacteria under anaerobic conditions, e.g. in underwater sediments.... The extent of mercury exposure in communities in South Africa is largely unknown. Dalvie and Ehrlich8 studied the effect of mercury inhalation in a community in Cape Town. Mercury concentrations in urine samples from residents in the vicinity of waste...

  17. Effects of Particulate Organic Matter Complexation and Photo-Irradiation on the Fate and Toxicity of Mercury(II) in Aqueous Systems

    Science.gov (United States)

    Gelfond, C. E.; Kocar, B. D.; Carrasquillo, A. J.

    2015-12-01

    This project investigates how interactions between mercury (Hg) and particulate organic matter (POM) affect the fate, transport, and toxicity of Hg in the environment. Previous studies have evaluated the coordination of dissolved organic matter (DOM) with Hg, but the coordination of POM with Hg has not been thoroughly addressed. Owing to a high density of reactive functional groups, POM will sorb appreciable quantities of Hg, resulting in a large pool of Hg susceptible to organic matter dependent transformations. Particulate organic carbon is also susceptible photolysis, hence chemical changes induced by irradiation by natural sunlight is also important. Further, photo-reduction of Hg(II) to elemental mercury in the presence of DOM has been observed, yet studies examining this process with Hg(II) complexed to POM are less exhaustive. Here, we illustrate that POM derived from fresh plant detritus is a powerful sorbent of Hg(II), and sorbent properties are altered during POM photolysis. Further, we examine redox transformations of Hg(II), and examine functional groups that contribute to mercury association with POM. Batch sorption isotherms of Hg to dark and irradiated POM from ground Phragmites australis ("common reed") were performed and data was collected using ICP-MS. Coordination of Hg to POM was lower in the irradiated samples, resulting from the decrease in Hg-associated (reduced) sulfur bearing functional groups as measured using X-ray adsorption near-edge spectroscopy (XANES) and extended x-ray adsorption fine structure (EXAFS). Further analysis of the dark and irradiated POM was performed using FT-IR microscopy and STXM to determine changes in distribution and alteration of functional groups responsible for Hg sorption to POM.

  18. Evaluation of potential dietary toxicity of heavy metals in some common Nigerian beverages: A look at antimony, tin and mercury

    Directory of Open Access Journals (Sweden)

    I.I. Roberts

    2011-11-01

    Full Text Available There is currently little information on the composition of heavy metals in beverages imported and locally produced in Nigeria. The study quantitatively determined the composition of antimony (Sb, tin (Sn and mercury (Hg in 50 different beverage samples and evaluated the extent of violation of guideline values. Analysis of the beverage samples for the presence of Sb, Sn, and Hg was carried out using an atomic absorption spectrophotometer (AAS 929. The mean values detected for mercury, tin and antimony (±SE in fruit juices and soft drinks were 2.39±0.25, 3.66±0.22 and 0.49±0.048 μg/l; 2.93±0.34, 3.60±0.46 and 0.49±0.10 μg/l in dairy drinks and 0.94±0.02, 4.34±0.48 and 0.48±0.05 μg/l in bottled water samples respectively. While antimony detected in all products was below guideline values, mercury and tin were above the acceptable levels established by the World Health Organization, United States Environmental Protection Agency and European Union in most samples tested.

  19. Method for Examining Acute Inhalation Toxicity of 44 Species of Indoor Coating%44种室内装潢涂料急性吸入毒性及检测方法

    Institute of Scientific and Technical Information of China (English)

    胡红; 周永贵; 李真观

    2001-01-01

    [Objective] This study was to establish a method for assessment of acute inhalation toxicity of coating,to explore the related factors affecting the toxicity of indoor coating,and to provide the technical basis for the safety and hygiene quality management of indoor coating. [Methods] The acute inhalation toxicity and total Volatile Organic Compounds (TVOC) were identified for 44 species in 6 categories of indoor coating,verifying the method of the measurement and assessment. [Results] The 44 species of indoor coating were classified according to both the acute inhalation toxicity and respiratory tract irritation,the aqueous coating such as emulsion paint etc belongs to class 0,the most of organic solvent coating to class Ⅱ or Ⅲ,and a few to Ⅳ. The certain kinds of coating can cause the damage of respiratory tract and lung tissue in degree from Ⅰ to Ⅱ in animal. The significant positive association was seen among the acute inhalation toxicity,respiratory tract irritation and the TVOC value of the coating. [Conclusion] Toxicity of the organic solvent coating is higher than that of the aqueous coating,and was related to the TVOC values. The toxicity of different kinds of coating can be efficiently identified by the acute inhalation toxicity classification and pathological findings described in this paper.%[目的] 建立涂料急性吸入毒性检测方法和评价标准,探讨影响室内装潢涂料毒性的有关因素,为室内装潢涂料安全卫生质量的管理提供技术依据。 [方法] 通过44种室内装潢涂料急性吸入毒性和总挥发性有机物(TVOC)含量的测试,验证上述测试及评价方法的科学性和可行性。 [结果] 检测了6大类44种涂料,其中乳胶漆等水性涂料急性吸入毒性和呼吸道刺激性均为0级;溶剂型涂料急性吸入毒性大多在Ⅱ至Ⅲ级,个别达到Ⅳ级,并引起实验动物呼吸道和肺组织Ⅰ~Ⅱ级损伤。涂料的急性

  20. Zuotai and HgS differ from HgCl2 and methyl mercury in Hg accumulation and toxicity in weanling and aged rats.

    Science.gov (United States)

    Zhang, Bin-Bin; Li, Wen-Kai; Hou, Wei-Yu; Luo, Ya; Shi, Jing-Zhen; Li, Cen; Wei, Li-Xin; Liu, Jie

    2017-09-15

    Mercury sulfides are used in Ayurvedic medicines, Tibetan medicines, and Chinese medicines for thousands of years and are still used today. Cinnabar (α-HgS) and metacinnabar (β-HgS) are different from mercury chloride (HgCl2) and methylmercury (MeHg) in their disposition and toxicity. Whether such scenario applies to weanling and aged animals is not known. To address this question, weanling (21d) and aged (450d) rats were orally given Zuotai (54% β-HgS, 30mg/kg), HgS (α-HgS, 30mg/kg), HgCl2 (34.6mg/kg), or MeHg (MeHgCl, 3.2mg/kg) for 7days. Accumulation of Hg in kidney and liver, and the toxicity-sensitive gene expressions were examined. Animal body weight gain was decreased by HgCl2 and to a lesser extent by MeHg, but unaltered after Zuotai and HgS. HgCl2 and MeHg produced dramatic tissue Hg accumulation, increased kidney (kim-1 and Ngal) and liver (Ho-1) injury-sensitive gene expressions, but such changes are absent or mild after Zuotai and HgS. Aged rats were more susceptible than weanling rats to Hg toxicity. To examine roles of transporters in Hg accumulation, transporter gene expressions were examined. The expression of renal uptake transporters Oat1, Oct2, and Oatp4c1 and hepatic Oatp2 was decreased, while the expression of renal efflux transporter Mrp2, Mrp4 and Mdr1b was increased following HgCl2 and MeHg, but unaffected by Zuotai and HgS. Thus, Zuotai and HgS differ from HgCl2 and MeHg in producing tissue Hg accumulation and toxicity, and aged rats are more susceptible than weanling rats. Transporter expression could be adaptive means to reduce tissue Hg burden. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Inhalation Toxicology Research Institute annual report, October 1, 1993--September 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Belinsky, S. A.; Hoover, M. D.; Bradley, P. L. [eds.

    1994-11-01

    This document from the Inhalation Toxicology Research Institute includes annual reports in the following general areas: (I) Aerosol Technology and Characterization of Airborne Materials; (II) Deposition, transport, and clearance of inhaled Toxicants; (III) Metabolism and Markers of Inhaled Toxicants; (IV) Carcinogenic Responses to Toxicants; (V) Mechanisms of carcinogenic response to Toxicants; (VI) Non carcinogenic responses to inhaled toxicants; (VII) Mechanisms of noncarcinogenic Responses to Inhaled Toxicants; (VIII) The application of Mathematical Modeling to Risk Estimates. 9 appendices are also included. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  2. Mercury poisoning in wildlife

    Science.gov (United States)

    Heinz, G.H.; Fairbrother, Anne; Locke, Louis N.; Hoff, Gerald L.

    1996-01-01

    Mercury is an intriguing contaminant because it has complex chemical properties, a wide range of harmful effects, and an infinite persistence in the environment. Die-offs of wildlife due to mercury have occurred in many countries, especially before mercury seed dressings were banned. Today, most mercury problems are associated with aquatic environments. Methylmercury, the most toxic chemical form, attacks many organ systems, but damage to the central nervous system is most severe. Harmful wet-weight concentrations of mercury, as methylmercury, in the tissues of adult birds and mammals range from about 8-30 ppm in the brain, 20-60 ppm in liver, 20-60 ppm in kidney, and 15-30 ppm in muscle. Young animals may be more sensitive.

  3. Analysis of toxicity produced by inhalation of trichloroethylene within rat and mice`s respiratory epithelium; Comparazione del danno indotto dall`inalazione di tricloroetilene nell`epitelio nasale e tracheobronchiale del ratto e del topo

    Energy Technology Data Exchange (ETDEWEB)

    Mancuso, M.T.; Fravolini, M.E.; Parasacchi, P.; Lombardi, C.C.; Giovanetti, A. [ENEA, Casaccia (Italy). Area Energia Ambiente e Salute

    1994-05-01

    The aim of this study was to define the sites of cytotoxicity within the respiratory tract (nasal cavity and tracheobronchial tree) after acute inhalation of trichloroethylene (TCE), an organic solvent requiring metabolic activation by cytochrome P-450 enzymatic system to exert its toxic effects. Two animals species, rats and mice, were exposed to 3500 and 7000 ppm of TCE for 30 minutes. The morphological analysis of the respiratory epithelium has underlined a species-specific difference in the cellular sensitivity after treatment with TCE. This work is a part of ENEA (Italian Agency for New Technologies, Energy and the Environment) INTO program, environmental department, sector of effects on man and ecosystem.

  4. Combined exposure to lead, inorganic mercury and methylmercury shows deviation from additivity for cardiovascular toxicity in rats.

    Science.gov (United States)

    Wildemann, Tanja M; Weber, Lynn P; Siciliano, Steven D

    2015-08-01

    Environmental exposure to metal mixtures in the human population is common. Mixture risk assessments are often challenging because of a lack of suitable data on the relevant mixture. A growing number of studies show an association between lead or mercury exposure and cardiovascular effects. We investigated the cardiovascular effects of single metal exposure or co-exposure to methylmercury [MeHg(I)], inorganic mercury [Hg(II)] and lead [Pb(II)]. Male Wistar rats received four different metal mixtures for 28 days through the drinking water. The ratios of the metals were based on reference and environmental exposure values. Blood and pulse pressure, cardiac output and electrical activity of the heart were selected as end-points. While exposure to only MeHg(I) increased the systolic blood pressure and decreased cardiac output, the effects were reversed with combined exposures (antagonism). In contrast to these effects, combined exposures negatively affected the electrical activity of the heart (synergism). Thus, it appears that estimates of blood total Hg levels need to be paired with estimates of what species of mercury dominate exposure as well as whether lead co-exposure is present to link total blood Hg levels to cardiovascular effects. Based on current human exposure data and our results, there may be an increased risk of cardiac events as a result of combined exposures to Hg(II), MeHg(I) and Pb(II). This increased risk needs to be clarified by analyzing lead and Hg exposure data in relation to cardiac electrical activity in epidemiological studies.

  5. Advances in understanding the mechanisms of mercury toxicity in wild golden grey mullet (Liza aurata) by (1)H NMR-based metabolomics.

    Science.gov (United States)

    Cappello, Tiziana; Pereira, Patrícia; Maisano, Maria; Mauceri, Angela; Pacheco, Mário; Fasulo, Salvatore

    2016-12-01

    Mercury (Hg) is recognized as a dangerous contaminant due to its bioaccumulation and biomagnification within trophic levels, leading to serious health risks to aquatic biota. Therefore, there is an urgent need to unravel the mechanisms underlying the toxicity of Hg. To this aim, a metabolomics approach based on protonic nuclear magnetic resonance ((1)H NMR), coupled with chemometrics, was performed on the gills of wild golden grey mullets L. aurata living in an Hg-polluted area in Ria de Aveiro (Portugal). Gills were selected as target organ due to their direct and continuous interaction with the surrounding environment. As a consequence of accumulated inorganic Hg and methylmercury, severe changes in the gill metabolome were observed, indicating a compromised health status of mullets. Numerous metabolites, i.e. amino acids, osmolytes, carbohydrates, and nucleotides, were identified as potential biomarkers of Hg toxicity in fish gills. Specifically, decrease of taurine and glycerophosphocholine, along with increased creatine level, suggested Hg interference with the ion-osmoregulatory processes. The rise of lactate indicated anaerobic metabolism enhancement. Moreover, the increased levels of amino acids suggested the occurrence of protein catabolism, further supported by the augmented alanine, involved in nitrogenous waste excretion. Increased level of isobutyrate, a marker of anoxia, was suggestive of onset of hypoxic stress at the Hg contaminated site. Moreover, the concomitant reduction in glycerophosphocholine and phosphocholine reflected the occurrence of membrane repair processes. Finally, perturbation in antioxidant defence system was revealed by the depletion in glutathione and its constituent amino acids. All these data were also compared to the differential Hg-induced metabolic responses previously observed in liver of the same mullets (Brandão et al., 2015). Overall, the environmental metabolomics approach demonstrated its effectiveness in the

  6. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

  7. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

  8. Comparative metalloproteomic approaches for the investigation proteins involved in the toxicity of inorganic and organic forms of mercury in rice (Oryza sativa L.) roots.

    Science.gov (United States)

    Li, Yunyun; Zhao, Jiating; Li, Yu-Feng; Xu, Xiaohan; Zhang, Bowen; Liu, Yongjie; Cui, Liwei; Li, Bai; Gao, Yuxi; Chai, Zhifang

    2016-07-13

    The toxicity mechanisms of rice roots under inorganic mercury (IHg) or methylmercury (MeHg) stress were investigated using metalloproteomic approaches. Rice seedlings were cultivated in nutrient solutions with IHg or MeHg for three weeks. Proteins were extracted from the roots and separated by two-dimensional electrophoresis (2-DE). Differentially expressed proteins were analyzed using ESI-MS/MS and identified by PMF. 26 and 29 protein spots were differentially expressed in the IHg- and MeHg-exposed roots, respectively. The proteins responsive to Hg exposure are involved in antioxidative defense, sulfur and glutathione metabolism, carbohydrate and energy metabolism, programmed cell death, and pathogen defense. Chitinase and salt stress-induced proteins exhibited a greater differentially expression in response to MeHg stress compared to IHg stress. Hg-binding proteins were detected by the combined use of 1-DE, SRXRF, and ESI-MS/MS. The results showed that Hg was bound to proteins of 15-25 kDa in rice roots under Hg stress. The Hg contents in the band under IHg stress were remarkably higher than those under MeHg. Hg binds to proteins, which leads to irreversible damage of root growth. Rice roots changed the related protein expression levels in response to Hg stress. These results may provide new insights into the mechanism of toxicity of IHg and MeHg in rice.

  9. Chronic mercury exposure in Late Neolithic/Chalcolithic populations in Portugal from the cultural use of cinnabar

    Science.gov (United States)

    Emslie, Steven D.; Brasso, Rebecka; Patterson, William P.; Carlos Valera, António; McKenzie, Ashley; Maria Silva, Ana; Gleason, James D.; Blum, Joel D.

    2015-10-01

    Cinnabar is a natural mercury sulfide (HgS) mineral of volcanic or hydrothermal origin that is found worldwide. It has been mined prehistorically and historically in China, Japan, Europe, and the Americas to extract metallic mercury (Hg0) for use in metallurgy, as a medicinal, a preservative, and as a red pigment for body paint and ceramics. Processing cinnabar via combustion releases Hg0 vapor that can be toxic if inhaled. Mercury from cinnabar can also be absorbed through the gut and skin, where it can accumulate in organs and bone. Here, we report moderate to high levels of total mercury (THg) in human bone from three Late Neolithic/Chalcolithic (5400-4100 B.P.) sites in southern Portugal that were likely caused by cultural use of cinnabar. We use light stable isotope and Hg stable isotope tracking to test three hypotheses on the origin of mercury in this prehistoric human bone. We traced Hg in two individuals to cinnabar deposits near Almadén, Spain, and conclude that use of this mineral likely caused mild to severe mercury poisoning in the prehistoric population. Our methods have applications to bioarchaeological investigations worldwide, and for tracking trade routes and mobility of prehistoric populations where cinnabar use is documented.

  10. Elemental mercury poisoning probably causes cortical myoclonus.

    Science.gov (United States)

    Ragothaman, Mona; Kulkarni, Girish; Ashraf, Valappil V; Pal, Pramod K; Chickabasavaiah, Yasha; Shankar, Susarla K; Govindappa, Srikanth S; Satishchandra, Parthasarthy; Muthane, Uday B

    2007-10-15

    Mercury toxicity causes postural tremors, commonly referred to as "mercurial tremors," and cerebellar dysfunction. A 23-year woman, 2 years after injecting herself with elemental mercury developed disabling generalized myoclonus and ataxia. Electrophysiological studies confirmed the myoclonus was probably of cortical origin. Her deficits progressed over 2 years and improved after subcutaneous mercury deposits at the injection site were surgically cleared. Myoclonus of cortical origin has never been described in mercury poisoning. It is important to ask patients presenting with jerks about exposure to elemental mercury even if they have a progressive illness, as it is a potentially reversible condition as in our patient.

  11. Chemical Form Matters: Differential Accumulation of Mercury Following Inorganic and Organic Mercury Exposures in Zebrafish Larvae

    Energy Technology Data Exchange (ETDEWEB)

    Korbas, Malgorzata; MacDonald, Tracy C.; Pickering, Ingrid J.; George, Graham N.; Krone, Patrick H. (Saskatchewan)

    2013-04-08

    Mercury, one of the most toxic elements, exists in various chemical forms each with different toxicities and health implications. Some methylated mercury forms, one of which exists in fish and other seafood products, pose a potential threat, especially during embryonic and early postnatal development. Despite global concerns, little is known about the mechanisms underlying transport and toxicity of different mercury species. To investigate the impact of different mercury chemical forms on vertebrate development, we have successfully combined the zebrafish, a well-established developmental biology model system, with synchrotron-based X-ray fluorescence imaging. Our work revealed substantial differences in tissue-specific accumulation patterns of mercury in zebrafish larvae exposed to four different mercury formulations in water. Methylmercury species not only resulted in overall higher mercury burdens but also targeted different cells and tissues than their inorganic counterparts, thus revealing a significant role of speciation in cellular and molecular targeting and mercury sequestration. For methylmercury species, the highest mercury concentrations were in the eye lens epithelial cells, independent of the formulation ligand (chloride versus L-cysteine). For inorganic mercury species, in absence of L-cysteine, the olfactory epithelium and kidney accumulated the greatest amounts of mercury. However, with L-cysteine present in the treatment solution, mercuric bis-L-cysteineate species dominated the treatment, significantly decreasing uptake. Our results clearly demonstrate that the common differentiation between organic and inorganic mercury is not sufficient to determine the toxicity of various mercury species.

  12. Chemical form matters: differential accumulation of mercury following inorganic and organic mercury exposures in zebrafish larvae.

    Science.gov (United States)

    Korbas, Malgorzata; Macdonald, Tracy C; Pickering, Ingrid J; George, Graham N; Krone, Patrick H

    2012-02-17

    Mercury, one of the most toxic elements, exists in various chemical forms each with different toxicities and health implications. Some methylated mercury forms, one of which exists in fish and other seafood products, pose a potential threat, especially during embryonic and early postnatal development. Despite global concerns, little is known about the mechanisms underlying transport and toxicity of different mercury species. To investigate the impact of different mercury chemical forms on vertebrate development, we have successfully combined the zebrafish, a well-established developmental biology model system, with synchrotron-based X-ray fluorescence imaging. Our work revealed substantial differences in tissue-specific accumulation patterns of mercury in zebrafish larvae exposed to four different mercury formulations in water. Methylmercury species not only resulted in overall higher mercury burdens but also targeted different cells and tissues than their inorganic counterparts, thus revealing a significant role of speciation in cellular and molecular targeting and mercury sequestration. For methylmercury species, the highest mercury concentrations were in the eye lens epithelial cells, independent of the formulation ligand (chloride versusl-cysteine). For inorganic mercury species, in absence of l-cysteine, the olfactory epithelium and kidney accumulated the greatest amounts of mercury. However, with l-cysteine present in the treatment solution, mercuric bis-l-cysteineate species dominated the treatment, significantly decreasing uptake. Our results clearly demonstrate that the common differentiation between organic and inorganic mercury is not sufficient to determine the toxicity of various mercury species.

  13. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2004-12-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems.

  14. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2004-12-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems.

  15. Inhaled Corticosteroids

    Directory of Open Access Journals (Sweden)

    Peter J. Barnes

    2010-03-01

    Full Text Available Inhaled corticosteroids (ICS are the most effective controllers of asthma. They suppress inflammation mainly by switching off multiple activated inflammatory genes through reversing histone acetylation via the recruitment of histone deacetylase 2 (HDAC2. Through suppression of airway inflammation ICS reduce airway hyperresponsiveness and control asthma symptoms. ICS are now first-line therapy for all patients with persistent asthma, controlling asthma symptoms and preventing exacerbations. Inhaled long-acting β2-agonists added to ICS further improve asthma control and are commonly given as combination inhalers, which improve compliance and control asthma at lower doses of corticosteroids. By contrast, ICS provide much less clinical benefit in COPD and the inflammation is resistant to the action of corticosteroids. This appears to be due to a reduction in HDAC2 activity and expression as a result of oxidative stress. ICS are added to bronchodilators in patients with severe COPD to reduce exacerbations. ICS, which are absorbed from the lungs into the systemic circulation, have negligible systemic side effects at the doses most patients require, although the high doses used in COPD has some systemic side effects and increases the risk of developing pneumonia.

  16. Toxic Elements

    DEFF Research Database (Denmark)

    Hajeb, Parvaneh; Shakibazadeh, Shahram; Sloth, Jens Jørgen

    2016-01-01

    Food is considered the main source of toxic element (arsenic, cadmium, lead, and mercury) exposure to humans, and they can cause major public health effects. In this chapter, we discuss the most important sources for toxic element in food and the foodstuffs which are significant contributors...... to human exposure. The occurrence of each element in food classes from different regions is presented. Some of the current toxicological risk assessments on toxic elements, the human health effect of each toxic element, and their contents in the food legislations are presented. An overview of analytical...... techniques and challenges for determination of toxic elements in food is also given....

  17. Changes in miRNA Expression Profiling during Neuronal Differentiation and Methyl Mercury-Induced Toxicity in Human in Vitro Models

    Directory of Open Access Journals (Sweden)

    Giorgia Pallocca

    2014-08-01

    Full Text Available MicroRNAs (miRNAs are implicated in the epigenetic regulation of several brain developmental processes, such as neurogenesis, neuronal differentiation, neurite outgrowth, and synaptic plasticity. The main aim of this study was to evaluate whether miRNA expression profiling could be a useful approach to detect in vitro developmental neurotoxicity. For this purpose, we assessed the changes in miRNA expression caused by methyl mercury chloride (MeHgCl, a well-known developmental neurotoxicant, comparing carcinoma pluripotent stem cells (NT-2 with human embryonic stem cells (H9, both analyzed during the early stage of neural progenitor commitment into neuronal lineage. The data indicate the activation of two distinct miRNA signatures, one activated upon neuronal differentiation and another upon MeHgCl-induced toxicity. Particularly, exposure to MeHgCl elicited, in both neural models, the down-regulation of the same six out of the ten most up-regulated neuronal pathways, as shown by the up-regulation of the corresponding miRNAs and further assessment of gene ontology (GO term and pathway enrichment analysis. Importantly, some of these common miRNA-targeted pathways defined in both cell lines are known to play a role in critical developmental processes, specific for neuronal differentiation, such as axon guidance and neurotrophin-regulated signaling. The obtained results indicate that miRNAs expression profiling could be a promising tool to assess developmental neurotoxicity pathway perturbation, contributing towards improved predictive human toxicity testing.

  18. Antioxidant and neuroprotective activity of the extract from the seaweed, Halimeda incrassata (Ellis) Lamouroux, against in vitro and in vivo toxicity induced by methyl-mercury.

    Science.gov (United States)

    Linares, Adyary Fallarero; Loikkanen, Jarkko; Jorge, Mancini-Filho; Soria, René Barro; Novoa, Alexis Vidal

    2004-02-01

    A growing body of evidence suggests oxidative stress as part of the toxicity mechanism of methyl-mercury (MeHg) in cell cultures and animal models and so justifies the use of natural antioxidants as therapeutic alternatives. This research examines the effect of an aqueous extract from the marine seaweed Halimeda incrassata (Hi) against the oxidative stress induced by MeHg on in vitro and in vivo models. In GT1-7 mouse hypothalamic cell cultures, the extract of Hi increased cell viability and reduced ROS production after 24-h exposure to MeHgCl. Wistar rats, acutely intoxicated with MeHgCl, had reduced levels of serum and brain thiobarbituric reactive substances when treated with the Hi extract. Similarly, animals exposed to repeated doses of MeHgCl were protected by the seaweed extract from variations in body weight, food consumption and the appearance of neurological effects. This research supports the notion that oxidative stress is directly involved in MeHg intoxication, so that natural antioxidants, particularly those in the extract of Hi, can be useful therapeutic alternatives.

  19. Oral administration of Moringa oleifera oil but not coconut oil prevents mercury-induced testicular toxicity in rats.

    Science.gov (United States)

    Abarikwu, S O; Benjamin, S; Ebah, S G; Obilor, G; Agbam, G

    2017-02-01

    This study was conducted to compare the effects of administration of coconut oil (CO) and Moringa oleifera oil (MO) on testicular oxidative stress, sperm quality and steroidogenesis parameters in rats treated with mercury chloride (HgCl2 ). After 15 days of oral administration of CO (2 ml kg(-1) body weight) and MO (2 ml kg(-1) body weight) along with intraperitoneal (i.p.) administration of HgCl2 (5 mg kg(-1) body weight) alone or in combination, we found that CO treatment did not protect against HgCl2 -induced poor sperm quality (motility, count) as well as decreased testosterone level and 17β-hydroxysteroid dehydrogenase (17β-HSD) activity. Treatment with CO alone decreased glutathione (GSH), and glutathione peroxidase (GSH-Px) activities and increased malondialdehyde (MDA) level in rat's testis, whereas MO did not change these parameters. Cotreatment with MO prevented HgCl2 -induced testicular catalase (CAT) and superoxide dismutase (SOD) activities, poor sperm quality and low testosterone level and also blocks the adverse effect of CO+HgCl2 (2 ml kg(-1) body weight + 5 mg kg(-1) body weight) on the investigated endpoints. In conclusion, MO and not CO decreased the deleterious effects of HgCl2 on sperm quality and steroidogenesis in rats and also strengthen the antioxidant defence of the testes. Therefore, MO is beneficial as an antioxidant in HgCl2 -induced oxidative damage.

  20. 亚硒酸钠影响无机汞/甲基汞对青海弧菌Q67的毒性∗%Effect of sodium selenite withinorganic mercury/methyl-mercury on the toxicity of Vibrio qinghaiensis sp. -Q67

    Institute of Scientific and Technical Information of China (English)

    张博闻; 赵甲亭; 李云云; 李娜; 李柏; 吴刚; 高愈希

    2016-01-01

    Objective:Mercury is a global pollutant and is listed as priority pollutants by many international organizationsbecause of its persist-ence in the environment, the bioaccumulation and toxicity in the food chain. The toxic effect of inorganic mercury( HgCl2 ) , methyl-mercury( Me-HgCl) and selenium(Na2SeO3)alone and their combinationon Vibrio qinghaiensis sp. -Q67(Q67) was studied. Methods:Q67 in the luminescent bacteria was used as the subject, combined with high-throughput microplate detection technology, with EC50 ( half maximal effective concentra-tion) as a measure index of the toxicity. Different exposure concentrations of inorganic mercury, methyl-mercury and selenium were used to deter-mine the luminous inhibition rate. Results:The EC50 value of inorganic mercury(0. 29687 mg/L) was significantly higher than that of methylmercu-ry(0. 08964 mg/L). When the combined mercury and selenium was exposed at the low concentrations of mercury, the luminous inhibition rate of Q67 has decreased. Conclusion:The toxicity of methylmercury to Q67 is stronger than that of inorganic mercury. Acertain antagonism is produced by sodium selenite with inorganic mercury and methylmercury at low concentrations, with that of selenium to methylmercury more significant.%目的::研究无机汞(HgCl2)、甲基汞(MeHgCl)和硒(Na2SeO3)单独及联合暴露下对青海弧菌Q67(Vibrio qing-haiensis sp.-Q67)毒性效应。方法:以发光菌中的青海弧菌Q67为受试生物,结合微孔板高通量检测技术,借用半数最大效应浓度( EC50)作为衡量毒性强弱的指标。用不同浓度的无机汞、甲基汞以及硒对其暴露,测定其发光抑制率。结果:无机汞的EC50值(0.29687mg/L)高于甲基汞的EC50值(0.08964mg/L)。硒汞联合暴露时,汞在低浓度的条件下,青海弧菌Q67的发光抑制率都有所降低。结论:甲基汞对青海弧菌Q67的毒性作用明显强于无机汞。亚硒酸钠与低浓度条件下的无机汞和

  1. Zinc toxicology following particulate inhalation

    Directory of Open Access Journals (Sweden)

    Cooper Ross

    2008-01-01

    Full Text Available The current mini-review describes the toxic effects of zinc inhalation principally in the workplace and associated complications with breathing and respiration. The International Classification of Functioning, Disability and Health Criteria were used to specifically select articles. Most of the commercial production of zinc involves the galvanizing of iron and the manufacture of brass. The recommended daily allowance for adults is 15 mg zinc/day. Metal fume fever associated with inhalation of fumes of ZnO is characterized by fatigue, chills, fever, myalgias, cough, dyspnea, leukocytosis, thirst, metallic taste and salivation. ZnCl 2 inhalation results in edema in the alveolar surface and the protein therein the lavage fluid is elevated. Particular pathological changes associated with zinc intoxication include: pale mucous membranes; jaundice; numerous Heinz bodies; and marked anemia. Adequate ambient air monitors for permissible exposure limits, excellent ventilation and extraction systems, and approved respirators are all important in providing adequate protection.

  2. Methodological approach for the assessment of acute inhalation toxicity of smoke ammunitions by in silico, in vitro and in vivo modelling

    NARCIS (Netherlands)

    Pradines, E.; Glacial, F.; Medus, D.; Stiee, E.; Fedou, F.; Hulst, M. van; Klerk, W.P.C. de

    2015-01-01

    Assessing the toxicity of military pyrotechnic products is a growing challenge in the current context of Human and Environment protection. The Allied Ordnance Publication (AOP) 45 and the Standard NATO Agreement (STANAG) 4588 “Guidelines for toxicity testing of smokes, obscurants and pyrotechnics

  3. Inhalation Toxicology. V. Evaluation of Relative Toxicity to Rats of Thermal Decomposition Products from Two Aircraft Seat Fire-Blocking Materials.

    Science.gov (United States)

    1985-11-01

    only. The relative toxicity of the combustion gases was measured by determining time-to-incapacitation (ti) in the laboratory rat , the same endpoint... the laboratory rat was the measured response used to compare the relative toxicity of the combustion gases produced from the two materials. Because of

  4. Methodological approach for the assessment of acute inhalation toxicity of smoke ammunitions by in silico, in vitro and in vivo modelling

    NARCIS (Netherlands)

    Pradines, E.; Glacial, F.; Medus, D.; Stiee, E.; Fedou, F.; Hulst, M. van; Klerk, W.P.C. de

    2015-01-01

    Assessing the toxicity of military pyrotechnic products is a growing challenge in the current context of Human and Environment protection. The Allied Ordnance Publication (AOP) 45 and the Standard NATO Agreement (STANAG) 4588 “Guidelines for toxicity testing of smokes, obscurants and pyrotechnics mi

  5. Ecosystem conceptual model- Mercury

    Science.gov (United States)

    Alpers, Charles N.; Eagles-Smith, Collin A.; Foe, Chris; Klasing, Susan; Marvin-DiPasquale, Mark C.; Slotton, Darell G.; Windham-Myers, Lisamarie

    2008-01-01

    Mercury has been identified as an important contaminant in the Delta, based on elevated concentrations of methylmercury (a toxic, organic form that readily bioaccumulates) in fish and wildlife. There are health risks associated with human exposure to methylmercury by consumption of sport fish, particularly top predators such as bass species. Original mercury sources were upstream tributaries where historical mining of mercury in the Coast Ranges and gold in the Sierra Nevada and Klamath-Trinity Mountains caused contamination of water and sediment on a regional scale. Remediation of abandoned mine sites may reduce local sources in these watersheds, but much of the mercury contamination occurs in sediments stored in the riverbeds, floodplains, and the Bay- Delta, where scouring of Gold-Rush-era sediment represents an ongoing source.Conversion of inorganic mercury to toxic methylmercury occurs in anaerobic environments including some wetlands. Wetland restoration managers must be cognizant of potential effects on mercury cycling so that the problem is not exacerbated. Recent research suggests that wettingdrying cycles can contribute to mercury methylation. For example, high marshes (inundated only during the highest tides for several days per month) tend to have higher methylmercury concentrations in water, sediment, and biota compared with low marshes, which do not dry out completely during the tidal cycle. Seasonally inundated flood plains are another environment experiencing wetting and drying where methylmercury concentrations are typically elevated. Stream restoration efforts using gravel injection or other reworking of coarse sediment in most watersheds of the Central Valley involve tailings from historical gold mining that are likely to contain elevated mercury in associated fines. Habitat restoration projects, particularly those involving wetlands, may cause increases in methylmercury exposure in the watershed. This possibility should be evaluated.The DRERIP

  6. Mercury Methylation and Environmental Effects of Inactive Mercury Mines in the Circum-Pacific Region

    Science.gov (United States)

    Gray, J. E.

    2001-05-01

    Mercury mines worldwide contain of some the highest concentrations of mercury on earth, and as a result of local mercury contamination, these mines represent areas of environmental concern when mine-drainage enters downstream aquatic systems. The most problematic aspect of mine site mercury contamination is the conversion of inorganic mercury to highly toxic organic mercury compounds, such as methylmercury, and their subsequent uptake by aquatic organisms in surrounding ecosystems. Mercury and methylmercury concentrations were measured in sediment and water samples collected from several inactive mercury mines in Nevada, Alaska, and the Philippines, which are part of the circum-Pacific mineral belt. The mines studied represent different mercury deposit types and sizes, and climatic settings. Geochemical data collected from these mines indicate that areas surrounding hot-springs type mercury deposits generally have lower methylmercury concentrations than silica-carbonate mercury deposits. In hot-springs mercury deposits in Nevada and Alaska, ore is dominantly cinnabar with few acid-water generating minerals such as pyrite, and as a result, mine-water drainage has near neutral pH in which there is low solubility of mercury. Conversely, silica-carbonate deposits, such as Palawan, Philippines, contain abundant cinnabar and pyrite, and the resultant acidic-mine drainage generally has higher concentrations of mercury and methylmercury. Additional factors such as the proximity of mercury mines to wetlands, climatic effects, or mine wastes containing highly soluble mercury compounds potentially enhance mercury methylation. The Palawan mercury mine may be a unique example where several adverse environmental factors produced local mercury contamination, high mercury methylation, fish contamination, and mercury poisoning of humans that consumed these contaminated fish.

  7. Mercury and Your Health

    Science.gov (United States)

    ... the Risk of Exposure to Mercury Learn About Mercury What is Mercury What is Metallic mercury? Toxicological Profile ToxFAQs Mercury Resources CDC’s National Biomonitoring Program Factsheet on Mercury ...

  8. Scientific Opinion on the risk for public health related to the presence of mercury and methylmercury in food

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Contaminants in the Food Chain (CONTAM

    2012-12-01

    Full Text Available EFSA was asked by the European Commission to consider new developments regarding inorganic mercury and methylmercury toxicity and evaluate whether the Joint FAO/WHO Expert Committee on Food Additives (JECFA provisional tolerable weekly intakes for methylmercury of 1.6 µg/kg body weight (b.w. and of 4 µg/kg b.w. for inorganic mercury were still appropriate. In line with JECFA, the CONTAM Panel established a tolerable weekly intake (TWI for inorganic mercury of 4 µg/kg b.w., expressed as mercury. For methylmercury, new developments in epidemiological studies from the Seychelles Child Developmental Study Nutrition Cohort have indicated that n-3 long-chain polyunsaturated fatty acids in fish may counteract negative effects from methylmercury exposure. Together with the information that beneficial nutrients in fish may have confounded previous adverse outcomes in child cohort studies from the Faroe Islands, the Panel established a TWI for methylmercury of 1.3 µg/kg b.w., expressed as mercury. The mean dietary exposure across age groups does not exceed the TWI for methylmercury, with the exception of toddlers and other children in some surveys. The 95th percentile dietary exposure is close to or above the TWI for all age groups. High fish consumers, which might include pregnant women, may exceed the TWI by up to approximately six-fold. Unborn children constitute the most vulnerable group. Biomonitoring data from blood and hair indicate that methylmercury exposure is generally below the TWI in Europe, but higher levels are also observed. Exposure to methylmercury above the TWI is of concern. If measures to reduce methylmercury exposure are considered, the potential beneficial effects of fish consumption should also be taken into account. Dietary inorganic mercury exposure in Europe does not exceed the TWI, but inhalation exposure of elemental mercury from dental amalgam is likely to increase the internal inorganic mercury exposure; thus the TWI

  9. 环境汞污染对藻类的毒性效应及其影响因素%The environment mercury pollution toxicity effect to the alga and their influencing factors

    Institute of Scientific and Technical Information of China (English)

    秦捷; 赵文; 张鹏

    2011-01-01

    综述了汞污染对藻类的毒性效应及影响因素.水环境中汞主要以元素汞、无机汞和有机汞3种形式存在.藻类吸附汞主要分为胞外的快速吸附和胞内的缓慢富集,在安全浓度内,金属汞对藻生长有一定的促进作用,随着浓度增大,抑制藻生长或致死.汞进入藻体细胞后,藻类为了存活会产生一系列保护机制.藻类对汞的排斥和排出作用可能就是对汞耐性的一种重要机制.藻类也可以通过多种方式减少汞进入藻类细胞,以及通过与其他物质结合汞使其排出胞外.温度、pH、生物学因素等影响重金属对藻类的毒性作用.并就藻类对汞耐性和适应机理、利用藻类修复和监测重金属污染、藻类响应汞胁迫的信号转导途径及其保护机制等未来研究领域进行了展望.%The toxicity effects of mercury pollution on algae and influencing factors were reviewed in this paper. Mercury in water environment mainly exists in three forms such as elemental form, inorganic form and organic form. Absorption of mercury consists of algal extracellular rapid absorption and slow intracellular accumulation. In the safe concentration, the metallic mercury can promote the algal growth. However, with its concentration increases , algae growth is inhibited and even resulted in the death. Once mercury comes into the algal cells , the algae will trigger a series of protection mechanisms. The exclusion and elimination of mercury from algae cells may be an important tolerance mechanism. Algae can also reduce the intake of mercury into the algal cells by the various methods , and promote the discharge of mercury by combining with other substances. Temperature , pH and some biological factors can influence the toxicity of heavy metals to the algae. The mechanism of mercury tolerance and adaptation , repair and monitoring of heavy metals pollution using algae , the algal signal transduction pathway response to mercury stress and

  10. Basic Information about Mercury

    Science.gov (United States)

    ... other organic compounds, elemental (metallic) mercury, and inorganic mercury compounds. Methylmercury and other organic mercury compounds are formed when mercury combines with carbon. Microscopic ...

  11. Mitochondrial complex II-derived superoxide is the primary source of mercury toxicity in barley root tip.

    Science.gov (United States)

    Tamás, Ladislav; Zelinová, Veronika

    2017-02-01

    Enhanced superoxide generation and significant inhibition of succinate dehydrogenase (SDH) activity followed by a strong reduction of root growth were detected in barley seedlings exposed to a 5μM Hg concentration for 30min, which increased further in an Hg dose-dependent manner. While at a 25μM Hg concentration no cell death was detectable, a 50μM Hg treatment triggered cell death in the root meristematic zone, which was markedly intensified after the treatment of roots with 100μM Hg and was detectable in the whole root tips. Generation of superoxide and H2O2 was a very rapid response of root tips occurring even after 5min of exposure to Hg. Application of an NADPH oxidase inhibitor or the inhibition of electron flow in mitochondria by the inhibition of complex I did not influence the Hg-induced H2O2 production. Treatment of roots with thenoyltrifluoroacetone, a non-competitive inhibitor of SDH, markedly reduced root growth and induced both superoxide and H2O2 production in a dose dependent manner. Similar to results obtained in intact roots, Hg strongly inhibited SDH activity in the crude mitochondrial fraction and caused a considerable increase of superoxide production, which was markedly reduced by the competitive inhibitors of SDH. These results indicate that the mitochondrial complex II-derived superoxide is the primary source of Hg toxicity in the barley root tip.

  12. Planet Mercury

    Science.gov (United States)

    1974-01-01

    Mariner 10's first image of Mercury acquired on March 24, 1974. During its flight, Mariner 10's trajectory brought it behind the lighted hemisphere of Mercury, where this image was taken, in order to acquire important measurements with other instruments.This picture was acquired from a distance of 3,340,000 miles (5,380,000 km) from the surface of Mercury. The diameter of Mercury (3,031 miles; 4,878 km) is about 1/3 that of Earth.Images of Mercury were acquired in two steps, an inbound leg (images acquired before passing into Mercury's shadow) and an outbound leg (after exiting from Mercury's shadow). More than 2300 useful images of Mercury were taken, both moderate resolution (3-20 km/pixel) color and high resolution (better than 1 km/pixel) black and white coverage.

  13. Coal fired flue gas mercury emission controls

    CERN Document Server

    Wu, Jiang; Pan, Weiguo; Pan, Weiping

    2015-01-01

    Mercury (Hg) is one of the most toxic heavy metals, harmful to both the environment and human health. Hg is released into the atmosphere from natural and anthropogenic sources and its emission control has caused much concern. This book introduces readers to Hg pollution from natural and anthropogenic sources and systematically describes coal-fired flue gas mercury emission control in industry, especially from coal-fired power stations. Mercury emission control theory and experimental research are demonstrated, including how elemental mercury is oxidized into oxidized mercury and the effect of

  14. Substance use -- inhalants

    Science.gov (United States)

    ... rags or toilet paper soaked with the chemical. Effects of Inhalants on the Brain When inhaled, the chemicals are absorbed by the ... to replace the ones that involved inhalant use. Exercise and eat healthy ... the harmful effects of inhalants. Avoid triggers. These triggers can be ...

  15. Mercury(6)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    31. Since Mariner Ten's flight, astronomers have been trying to find out more about Mercury. Telescopes, including the orbiting Hubble Space Telescope,cannot help much. They would be damaged by the bright light of the sun if they turned to look at Mercury. So, astronomers are studying Mercury from observatories on Earth. They are recording information about the planet's radiation.

  16. An evaluation of mercury offloading in two Central California elasmobranchs.

    Science.gov (United States)

    van Hees, Kelley E; Ebert, David A

    2017-03-02

    Elasmobranchs occupy high trophic levels, accumulate high concentrations of mercury in their tissues, and have high energetic levels of maternal investment to offspring, which may cause embryos to be exposed in utero to harmful concentrations of mercury. We investigated the maternal transfer of mercury in two common coastal elasmobranch species, Triakis semifasciata and Platyrhinoidis triseriata, to determine which reproductive parameters may influence mercury offloading, and whether embryos are at risk to mercury toxicity. Mercury concentration was measured in female muscle, female liver, and embryonic tissues. The behavior of mercury in adult female tissues differed between species, as liver mercury concentration was significantly correlated to muscle mercury concentration in P. triseriata but not in T. semifasciata. Embryos of both species were found with potentially harmful mercury concentrations in their muscle tissues. Embryo mercury concentration increased with female muscle mercury concentration, but the relationship to female liver mercury was more variable. The rate of mercury transfer and overall offloading potential were significantly greater in P. triseriata than T. semifasciata. It appears that female mercury concentration, either in muscle or liver, is an important influencing factor for mercury offloading, but the impact of the differing reproductive modes in these two species was less clear. More study on this subject will continue to elucidate the factors influencing mercury offloading in sharks and rays, and how contaminant risk affects populations on a whole.

  17. Chelation Therapy for Mercury Poisoning

    Directory of Open Access Journals (Sweden)

    Rong Guan

    2009-01-01

    Full Text Available Chelation therapy has been the major treatment for heavy metal poisoning. Various chelating agents have been developed and tested for treatment of heavy metal intoxications, including mercury poisoning. It has been clearly shown that chelating agents could rescue the toxicity caused by heavy metal intoxication, but the potential preventive role of chelating agents against heavy metal poisoning has not been explored much. Recent paper by Siddiqi and colleagues has suggested a protective role of chelating agents against mercury poisoning, which provides a promising research direction for broader application of chelation therapy in prevention and treatment of mercury poisoning.

  18. Mercury pollution in Malaysia.

    Science.gov (United States)

    Hajeb, Parvaneh; Jinap, S; Ismail, Ahmad; Mahyudin, Nor Ainy

    2012-01-01

    Although several studies have been published on levels of mercury contamination of the environment, and of food and human tissues in Peninsular Malaysia, there is a serious dearth of research that has been performed in East Malaysia (Sabah and Sarawak). Industry is rapidly developing in East Malaysia, and, hence, there is a need for establishing baseline levels of mercury contamination in environmental media in that part of the country by performing monitoring studies. Residues of total mercury and inorganic in food samples have been determined in nearly all previous studies that have been conducted; however, few researchers have analyzed samples for the presence of methlymercury residues. Because methylmercury is the most toxic form of mercury, and because there is a growing public awareness of the risk posed by methylmercury exposure that is associated with fish and seafood consumption, further monitoring studies on methylmercury in food are also essential. From the results of previous studies, it is obvious that the economic development in Malaysia, in recent years, has affected the aquatic environment of the country. Primary areas of environmental concern are centered on the rivers of the west Peninsular Malaysian coast, and the coastal waters of the Straits of Malacca, wherein industrial activities are rapidly expanding. The sources of existing mercury input to both of these areas of Malaysia should be studied and identified. Considering the high levels of mercury that now exists in human tissues, efforts should be continued, and accelerated in the future, if possible, to monitor mercury contamination levels in the coastal states, and particularly along the west Peninsular Malaysian coast. Most studies that have been carried out on mercury residues in environmental samples are dated, having been conducted 20-30 years ago; therefore, the need to collect much more and more current data is urgent. Furthermore, establishing baseline levels of mercury exposure to

  19. Study on the toxicity of inhaled alumina nanoparticles: impact of physicochemical properties and adsorption artifacts on the measurement of biological responses

    Energy Technology Data Exchange (ETDEWEB)

    Pailleux, M; Pourchez, J; Boudard, D; Cottier, M [LINA Laboratoire Interdisciplinaire d' etude des Nanoparticules Aerosolisees, F-42023, Saint-Etienne (France); Grosseau, P, E-mail: pailleux@emse.fr [Ecole Nationale Superieure des Mines de Saint-Etienne, Centre SPIN, LPMG, UMR CNRS 5148, F-42023, Saint-Etienne (France)

    2011-07-06

    This work aims at developping a multidisciplinary approach to highlight the correlation between the toxicity of alumina engineered nanoparticles (NP) and their physicochemical characteristics. Accuracy of measurements depends on cell production after contact with particles, but also depends on the ability of biomolecules to get adsorbed on the NP. That's why, mechanisms of biomolecules adsorption on NP must be fully understood to avoid misinterpretation of data.

  20. Epigenetic events determine tissue-specific toxicity of inhalational exposure to the genotoxic chemical 1,3-butadiene in male C57BL/6J mice.

    Science.gov (United States)

    Chappell, Grace; Kobets, Tetyana; O'Brien, Bridget; Tretyakova, Natalia; Sangaraju, Dewakar; Kosyk, Oksana; Sexton, Kenneth G; Bodnar, Wanda; Pogribny, Igor P; Rusyn, Ivan

    2014-12-01

    1,3-Butadiene (BD), a widely used industrial chemical and a ubiquitous environmental pollutant, is a known human carcinogen. Although genotoxicity is an established mechanism of the tumorigenicity of BD, epigenetic effects have also been observed in livers of mice exposed to the chemical. To better characterize the diverse molecular mechanisms of BD tumorigenicity, we evaluated genotoxic and epigenotoxic effects of BD exposure in mouse tissues that are target (lung and liver) and non-target (kidney) for BD-induced tumors. We hypothesized that epigenetic alterations may explain, at least in part, the tissue-specific differences in BD tumorigenicity in mice. We evaluated the level of N-7-(2,3,4-trihydroxybut-1-yl)guanine adducts and 1,4-bis-(guan-7-yl)-2,3-butanediol crosslinks, DNA methylation, and histone modifications in male C57BL/6 mice exposed to filtered air or 425 ppm of BD by inhalation (6 h/day, 5 days/week) for 2 weeks. Although DNA damage was observed in all three tissues of BD-exposed mice, variation in epigenetic effects clearly existed between the kidneys, liver, and lungs. Epigenetic alterations indicative of genomic instability, including demethylation of repetitive DNA sequences and alterations in histone-lysine acetylation, were evident in the liver and lung tissues of BD-exposed mice. Changes in DNA methylation were insignificant in the kidneys of treated mice, whereas marks of condensed heterochromatin and transcriptional silencing (histone-lysine trimethylation) were increased. These modifications may represent a potential mechanistic explanation for the lack of tumorigenesis in the kidney. Our results indicate that differential tissue susceptibility to chemical-induced tumorigenesis may be attributed to tissue-specific epigenetic alterations.

  1. Mercury(1)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    1.Mercury is the planet closest to the sun.It is thefastest moving planet.And it is the second smallestplanet in our solar system. 2.Mercury is very difficult to see.Its orbit isbetween us and the sun.So,we have to look toward thebright light of the sun to see it.The sunlight usuallyhides Mercury.When we can see it,it appears as a fuzzyball.

  2. Zanamivir Oral Inhalation

    Science.gov (United States)

    ... for inhaling powder) and five Rotadisks (circular foil blister packs each containing four blisters of medication). Zanamivir powder ... put a hole in or open any medication blister pack until inhaling a dose with the Diskhaler.Carefully ...

  3. Mercury cycling in peatland watersheds. Chapter 11.

    Science.gov (United States)

    Randall K. Kolka; Carl P.J. Mitchell; Jeffrey D. Jeremiason; Neal A. Hines; David F. Grigal; Daniel R. Engstrom; Jill K. Coleman-Wasik; Edward A. Nater; Edward B. Swain; Bruce A. Monson; Jacob A. Fleck; Brian Johnson; James E. Almendinger; Brian A. Branfireun; Patrick L. Brezonik; James B. Cotner

    2011-01-01

    Mercury (Hg) is of great environmental concern due to its transformation into the toxic methylmercury (MeHg) form that bioaccumulates within the food chain and causes health concerns for both humans and wildlife (U.S. Environmental Protection Agency 2002). Mercury can affect neurological development in fetuses and young children. In adults, exposure to Hg can lead to...

  4. Ecological effects, transport, and fate of mercury: a general review.

    Science.gov (United States)

    Boening, D W

    2000-06-01

    Mercury at low concentrations represents a major hazard to microorganisms. Inorganic mercury has been reported to produce harmful effects at 5 microg/l in a culture medium. Organomercury compounds can exert the same effect at concentrations 10 times lower than this. The organic forms of mercury are generally more toxic to aquatic organisms and birds than the inorganic forms. Aquatic plants are affected by mercury in water at concentrations of 1 mg/l for inorganic mercury and at much lower concentrations of organic mercury. Aquatic invertebrates widely vary in their susceptibility to mercury. In general, organisms in the larval stage are most sensitive. Methyl mercury in fish is caused by bacterial methylation of inorganic mercury, either in the environment or in bacteria associated with fish gills or gut. In aquatic matrices, mercury toxicity is affected by temperature, salinity, dissolved oxygen and water hardness. A wide variety of physiological, reproductive and biochemical abnormalities have been reported in fish exposed to sublethal concentrations of mercury. Birds fed inorganic mercury show a reduction in food intake and consequent poor growth. Other (more subtle) effects in avian receptors have been reported (i.e., increased enzyme production, decreased cardiovascular function, blood parameter changes, immune response, kidney function and structure, and behavioral changes). The form of retained mercury in birds is more variable and depends on species, target organ and geographical site. With few exceptions, terrestrial plants (woody plants in particular) are generally insensitive to the harmful effects of mercury compounds.

  5. Mercury in the South African environment

    CSIR Research Space (South Africa)

    Matooane, M

    2009-11-01

    Full Text Available This presentation highlights the toxic effects that over-exposure to mercury (Hg) might have on human health. This includes blindness, deafness, cerebral palsy, mental problems and abnormal reflexes and muscle tone. Hg emissions increasing globally...

  6. Development of an optical fiber probe for mercury detection

    OpenAIRE

    Pérez Hernández, Javier

    2008-01-01

    The organic form of mercury (methylmercury) is highly toxic, affecting the nervous system and even causing death. In the last years, human activities on coal combustion, waste incineration, gold mining and other industrial processes have raised the level of mercury in the atmosphere, rivers and other sources. Several public bodies have demonstrated that the direct detection of inorganic mercury (the precursor of mehtylmercury) will be beneficial in order to prevent mercury contamination. The ...

  7. Mercury(5)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    26. Mercury appears to have a center of iron thattakes up seventy-five percent 0f the planet. There isonly a thin outer covering of rock around the core. Someastronomers think most of Mercury's rock was explodedoff when the planet was hit by a huge object early in itshistory.

  8. Chronic mercury poisoning: Report of two siblings.

    Science.gov (United States)

    Yilmaz, Cahide; Okur, Mesut; Geylani, Hadi; Caksen, Hüseyin; Tuncer, Oğuz; Ataş, Bülent

    2010-01-01

    Mercury exists as organic inorganic and elementary forms in nature and is one of the most toxic metals that are poisonous for human beings. Mercury is commonly used in many different sectors of industry such as in insects formulas, agriculture products, lamps, batteries, paper, dyes, electrical/electronic devices, jewelry, and in dentistry. In this study, two siblings (one a 7-year-old boy and the other a 13 years old girl) are reported who developed chronic mercury poisoning as a result of long-term contact with batteries. Our aim is to emphasize the importance of mercury poisoning that is extremely rarely seen in childhood.

  9. Chronic mercury poisoning: Report of two siblings

    Directory of Open Access Journals (Sweden)

    Yilmaz Cahide

    2010-01-01

    Full Text Available Mercury exists as organic inorganic and elementary forms in nature and is one of the most toxic metals that are poisonous for human beings. Mercury is commonly used in many different sectors of industry such as in insects formulas, agriculture products, lamps, batteries, paper, dyes, electrical/electronic devices, jewelry, and in dentistry. In this study, two siblings (one a 7-year-old boy and the other a 13 years old girl are reported who developed chronic mercury poisoning as a result of long-term contact with batteries. Our aim is to emphasize the importance of mercury poisoning that is extremely rarely seen in childhood.

  10. Volcanic mercury in Pinus canariensis

    Science.gov (United States)

    Rodríguez Martín, José Antonio; Nanos, Nikos; Miranda, José Carlos; Carbonell, Gregoria; Gil, Luis

    2013-08-01

    Mercury (Hg) is a toxic element that is emitted to the atmosphere by both human activities and natural processes. Volcanic emissions are considered a natural source of mercury in the environment. In some cases, tree ring records taken close to volcanoes and their relation to volcanic activity over time are contradictory. In 1949, the Hoyo Negro volcano (La Palma-Canary Islands) produced significant pyroclastic flows that damaged the nearby stand of Pinus canariensis. Recently, 60 years after the eruption, we assessed mercury concentrations in the stem of a pine which survived volcano formation, located at a distance of 50 m from the crater. We show that Hg content in a wound caused by pyroclastic impacts (22.3 μg kg-1) is an order of magnitude higher than the Hg concentrations measured in the xylem before and after the eruption (2.3 μg kg-1). Thus, mercury emissions originating from the eruption remained only as a mark—in pyroclastic wounds—and can be considered a sporadic and very high mercury input that did not affect the overall Hg input in the xylem. In addition, mercury contents recorded in the phloem (9.5 μg kg-1) and bark (6.0 μg kg-1) suggest that mercury shifts towards non-living tissues of the pine, an aspect that can be related to detoxification in volcanism-adapted species.

  11. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

  12. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

  13. 玉红膏单次给药家兔体内汞的吸收及毒性%Mercury Absorption and Toxicity of Single Dose of Yuhong Ointment in Rabbits

    Institute of Scientific and Technical Information of China (English)

    孙新民; 王旗; 牟稷征; 王丽霞

    2011-01-01

    Objective; To study the toxicity and absorption of mercury following single dose transdermal administration of Yuhong ointment containing 0.4% calomel in rabbits. Method; Twelve Japanese white rabbits, half in male or female, were divided into three groups; control group, Yuhong ointment group and 0. 4% calomelgroup. The rabbits were given a single transdermal administration of 1. 56 g ? Kg"' (0. 039 g ? Cm" , corresponding to 2-fold of the human therapeutic dose). The contents of mercury in blood and main organs were measured by HG-AAS. The serum biochemical indexes including creatinine ( Cr) , BUN, AST, ALT were measured to reflex the function of liver and kidney. Result; The contents of blood mercury in the experimental groups showed no significant difference compared with control group, while the content of mercury didn' t increase obviously after single dose transdermal administration. The mercury contents of the experimental groups in liver and kidney were significantly higher than that of the control group, whereas there were no statistical significance in heart, spleen and brain. Among of the blood biochemical indexes, only ALT increased significantly in the experimental groups compared with that in the control group. Conclusion; There was little absorption of mercury and a definite accumulation of mercury in liver and kidney following single dosage transdermal administration of Yuhong ointment in rabbits.%目的:研究含0.4%轻粉的玉红膏单次给药后家兔体内汞的吸收及毒性,以考察玉红膏用药的安全性.方法:日本大耳白家兔12只,雌雄各半,分为3组,分别为基质(凡士林)对照组,玉红膏组,0.4%轻粉组.按1.56 g·kg-1(0.039 g·cm-2,相当于临床日用剂量的2倍)单次经皮给药,用氢化物-原子吸收法测定全血和主要脏器中的汞含量来确定体内汞的吸收情况,以血生化指标丙氨酸转氨酶(ALT),天冬氨酸转氨酶(AST),肌酐(Cr),血尿素氮(BUN)评价给药后对家兔

  14. Formal recycling of e-waste leads to increased exposure to toxic metals: an occupational exposure study from Sweden.

    Science.gov (United States)

    Julander, Anneli; Lundgren, Lennart; Skare, Lizbet; Grandér, Margaretha; Palm, Brita; Vahter, Marie; Lidén, Carola

    2014-12-01

    Electrical and electronic waste (e-waste) contains multiple toxic metals. However, there is currently a lack of exposure data for metals on workers in formal recycling plants. The objective of this study was to evaluate workers' exposure to metals, using biomarkers of exposure in combination with monitoring of personal air exposure. We assessed exposure to 20 potentially toxic metals among 55 recycling workers and 10 office workers at three formal e-waste recycling plants in Sweden. Workers at two of the plants were followed-up after 6 months. We collected the inhalable fraction and OFC (37-mm) fraction of particles, using personal samplers, as well as spot samples of blood and urine. We measured metal concentrations in whole blood, plasma, urine, and air filters using inductively coupled plasma-mass spectrometry following acid digestion. The air sampling indicated greater airborne exposure, 10 to 30 times higher, to most metals among the recycling workers handling e-waste than among the office workers. The exposure biomarkers showed significantly higher concentrations of chromium, cobalt, indium, lead, and mercury in blood, urine, and/or plasma of the recycling workers, compared with the office workers. Concentrations of antimony, indium, lead, mercury, and vanadium showed close to linear associations between the inhalable particle fraction and blood, plasma, or urine. In conclusion, our study of formal e-waste recycling shows that workers performing recycling tasks are exposed to multiple toxic metals.

  15. Assessing elemental mercury vapor exposure from cultural and religious practices.

    Science.gov (United States)

    Riley, D M; Newby, C A; Leal-Almeraz, T O; Thomas, V M

    2001-08-01

    Use of elemental mercury in certain cultural and religious practices can cause high exposures to mercury vapor. Uses include sprinkling mercury on the floor of a home or car, burning it in a candle, and mixing it with perfume. Some uses can produce indoor air mercury concentrations one or two orders of magnitude above occupational exposure limits. Exposures resulting from other uses, such as infrequent use of a small bead of mercury, could be well below currently recognized risk levels. Metallic mercury is available at almost all of the 15 botanicas visited in New York, New Jersey, and Pennsylvania, but botanica personnel often deny having mercury for sale when approached by outsiders to these religious and cultural traditions. Actions by public health authorities have driven the mercury trade underground in some locations. Interviews indicate that mercury users are aware that mercury is hazardous, but are not aware of the inhalation exposure risk. We argue against a crackdown by health authorities because it could drive the practices further underground, because high-risk practices may be rare, and because uninformed government intervention could have unfortunate political and civic side effects for some Caribbean and Latin American immigrant groups. We recommend an outreach and education program involving religious and community leaders, botanica personnel, and other mercury users.

  16. The sub-cellular fate of mercury in the liver of wild mullets (Liza aurata)--Contribution to the understanding of metal-induced cellular toxicity.

    Science.gov (United States)

    Araújo, Olinda; Pereira, Patrícia; Cesário, Rute; Pacheco, Mário; Raimundo, Joana

    2015-06-15

    Mercury is a recognized harmful pollutant in aquatic systems but still little is known about its sub-cellular partitioning in wild fish. Mercury concentrations in liver homogenate (whole organ load) and in six sub-cellular compartments were determined in wild Liza aurata from two areas - contaminated (LAR) and reference. Water and sediment contamination was also assessed. Fish from LAR displayed higher total mercury (tHg) organ load as well as in sub-cellular compartments than those from the reference area, reflecting environmental differences. However, spatial differences in percentage of tHg were only observed for mitochondria (Mit) and lysosomes plus microsomes (Lys+Mic). At LAR, Lys+Mic exhibited higher levels of tHg than the other fractions. Interestingly, tHg in Mit, granules (Gran) and heat-denaturable proteins was linearly correlated with the whole organ. Low tHg concentrations in heat stable proteins and Gran suggests that accumulated levels might be below the physiological threshold to activate those detoxification fractions.

  17. Elemental mercury poisoning caused by subcutaneous and intravenous injection: An unusual self-injury

    Directory of Open Access Journals (Sweden)

    Wale Jaywant

    2010-01-01

    Full Text Available Elemental mercury poisoning most commonly occurs through vapor inhalation as mercury is well absorbed through the lungs. Administering subcutaneous and intravenous elemental mercury is very uncommon but with only a few isolated case reports in the literature. We present an unusual case of elemental mercury poisoning in a 20-year-old young male who presented with chest pain, fever, and hemoptysis. He had injected himself subcutaneously with elemental mercury obtained from a sphygmomanometer. The typical radiographic findings in the chest, forearm, and abdomen are discussed, with a review of the literature.

  18. Elemental mercury poisoning caused by subcutaneous and intravenous injection: An unusual self-injury.

    Science.gov (United States)

    Wale, Jaywant; Yadav, Pankaj K; Garg, Shairy

    2010-05-01

    Elemental mercury poisoning most commonly occurs through vapor inhalation as mercury is well absorbed through the lungs. Administering subcutaneous and intravenous elemental mercury is very uncommon but with only a few isolated case reports in the literature. We present an unusual case of elemental mercury poisoning in a 20-year-old young male who presented with chest pain, fever, and hemoptysis. He had injected himself subcutaneously with elemental mercury obtained from a sphygmomanometer. The typical radiographic findings in the chest, forearm, and abdomen are discussed, with a review of the literature.

  19. 78 FR 69414 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2013-11-19

    ... pigments; Toxicity to Algae; Acute emulsion polymerization in Inhalation Toxicity in paper, textile, fiber, and Rats; Bacterial Reverse adhesives industries. Mutation; In Vitro Mammalian Chromosome...

  20. Lead, mercury, and cadmium in breast milk

    OpenAIRE

    Kadriye Yurdakök

    2015-01-01

    Toxic heavy metals are the major source of environmental pollution in this new millennium. Lead, mercury, and cadmium are the most common toxic heavy metals in the environment. There is no known function of these toxic heavy metals in the human body. In females, toxic heavy metals can be accumulated in maternal body before pregnancy and may be transferred to fetus through placenta and later, via breast milk. Lead previously accumulated in maternal bones can be mobilized along with calcium in ...

  1. Oral bioaccessibility and human exposure to anthropogenic and geogenic mercury in urban, industrial and mining areas

    NARCIS (Netherlands)

    Rodrigues, S.M.; Coelho, C.; Cruz, N.; Monteiro, R.J.R.; Henriques, B.; Duarte, A.C.; Romkens, P.F.A.M.; Pereira, E.

    2014-01-01

    The objective of this study was to characterize the link between bioaccessibility and fractionation of mercury (Hg) in soils and to provide insight into human exposure to Hg due to inhalation of airborne soil particles and hand-to-mouth ingestion of Hg-bearing soil. Mercury in soils from mining, urb

  2. Mercury speciation analysis in marine samples by HPLC-ICPMS

    DEFF Research Database (Denmark)

    Rasmussen, Rie Romme; Svendsen, Maja Erecius; Herbst, M. Birgitte Koch

    Mercury (Hg) is a naturally occurring element, which is found in the earth’s crust and can be released into the environment through both natural and anthropogenic processes. Mercury exists as elemental mercury (metallic), inorganic mercury and organic mercury (primarily methylmercury......). Methylmercury is highly toxic, particularly to the nervous system, and the developing brain is thought to be the most sensitive target organ for methylmercury toxicity. Methylmercury bioaccumulates and biomagnifies along the food chain and it is the most common mercury species in fish and seafood. Human...... hydrochloric acid by sonication. Hereby the protein-bound mercury species are released. The extracts were then centrifuged (10 min at 3170 x g) and the supernatant decanted (extraction step was repeated twice). The combined extracts were added 10 M sodium hydroxide to increase pH, following further dilution...

  3. Bioaccumulation syndrome: identifying factors that make some stream food webs prone to elevated mercury bioaccumulation

    OpenAIRE

    Ward, Darren M.; Nislow, Keith H.; Folt, Carol L.

    2010-01-01

    Mercury is a ubiquitous contaminant in aquatic ecosystems, posing a significant health risk to humans and wildlife that eat fish. Mercury accumulates in aquatic food webs as methylmercury (MeHg), a particularly toxic and persistent organic mercury compound. While mercury in the environment originates largely from anthropogenic activities, MeHg accumulation in freshwater aquatic food webs is not a simple function of local or regional mercury pollution inputs. Studies show that even sites with ...

  4. Inhalant Abuse and Dextromethorphan.

    Science.gov (United States)

    Storck, Michael; Black, Laura; Liddell, Morgan

    2016-07-01

    Inhalant abuse is the intentional inhalation of a volatile substance for the purpose of achieving an altered mental state. As an important, yet underrecognized form of substance abuse, inhalant abuse crosses all demographic, ethnic, and socioeconomic boundaries, causing significant morbidity and mortality in school-aged and older children. This review presents current perspectives on epidemiology, detection, and clinical challenges of inhalant abuse and offers advice regarding the medical and mental health providers' roles in the prevention and management of this substance abuse problem. Also discussed is the misuse of a specific "over-the-counter" dissociative, dextromethorphan.

  5. EDITORIAL: Mercury-free discharges for lighting

    Science.gov (United States)

    Haverlag, M.

    2007-07-01

    This special Cluster of articles in Journal of Physics D: Applied Physics covers the subject of mercury-free discharges that are being investigated by different light source researchers, as an alternative to existing mercury-containing lamps. The main driving force to move away from mercury-containing discharge light sources is connected to the environmentally unfriendly nature of mercury. After inhalation or direct contact, severe mercury exposure can lead to damage to human brain cells, the kidneys, the liver and the nervous system. For this reason, the use of mercury in products is becoming more and more restricted by different governmental bodies. In the lighting industry, however, many products still make use of mercury, for different reasons. The main reason is that mercury-containing products are, in most cases, more efficient than mercury-free products. For a realistic comparison of the environmental impact, the mercury-contamination due to electricity production must be taken into account, which depends on the type of fuel being used. For an average European fuel-mix, the amount of mercury that is released into the environment is around 29 μg kWh-1. This means that a typical 30 W TL lamp during a lifetime of 20,000 hours will release a total of about 20 mg mercury due to electricity production, which exceeds the total mercury dose in the lamp (more and more of which is being recycled) by a factor of 5-10 for a modern TL lamp. This illustrates that, quite apart from other environmental arguments like increased CO2 production, mercury-free alternatives that use more energy can in fact be detrimental for the total mercury pollution over the lifetime of the lamp. For this reason, the lighting industry has concentrated on lowering the mercury content in lamps as long as no efficient alternatives exist. Nevertheless, new initiatives for HID lamps and fluorescent lamps with more or less equal efficiency are underway, and a number of them are described in this

  6. Mercury and halogens in coal--Their role in determining mercury emissions from coal combustion

    Science.gov (United States)

    Kolker, Allan; Quick, Jeffrey C.; Senior, Connie L.; Belkin, Harvey E.

    2012-01-01

    Mercury is a toxic pollutant. In its elemental form, gaseous mercury has a long residence time in the atmosphere, up to a year, allowing it to be transported long distances from emission sources. Mercury can be emitted from natural sources such as volcanoes, or from anthropogenic sources, such as coal-fired powerplants. In addition, all sources of mercury on the Earth's surface can re-emit it from land and sea back to the atmosphere, from which it is then redeposited. Mercury in the atmosphere is present in such low concentrations that it is not considered harmful. Once mercury enters the aquatic environment, however, it can undergo a series of biochemical transformations that convert a portion of the mercury originally present to methylmercury, a highly toxic organic form of mercury that accumulates in fish and birds. Many factors contribute to creation of methylmercury in aquatic ecosystems, including mercury availability, sediment and nutrient load, bacterial influence, and chemical conditions. In the United States, consumption of fish with high levels of methylmercury is the most common pathway for human exposure to mercury, leading the U.S. Environmental Protection Agency (EPA) to issue fish consumption advisories in every State. The EPA estimates that 50 percent of the mercury entering the atmosphere in the United States is emitted from coal-burning utility powerplants. An EPA rule, known as MATS (for Mercury and Air Toxics Standards), to reduce emissions of mercury and other toxic pollutants from powerplants, was signed in December 2011. The rule, which is currently under review, specifies limits for mercury and other toxic elements, such as arsenic, chromium, and nickel. MATS also places limits on emission of harmful acid gases, such as hydrochloric acid and hydrofluoric acid. These standards are the result of a 2010 detailed nationwide program by the EPA to sample stack emissions and thousands of shipments of coal to coal-burning powerplants. The United

  7. Mercury Information Clearinghouse

    Energy Technology Data Exchange (ETDEWEB)

    Chad A. Wocken; Michael J. Holmes; Dennis L. Laudal; Debra F. Pflughoeft-Hassett; Greg F. Weber; Nicholas V. C. Ralston; Stanley J. Miller; Grant E. Dunham; Edwin S. Olson; Laura J. Raymond; John H. Pavlish; Everett A. Sondreal; Steven A. Benson

    2006-03-31

    The Canadian Electricity Association (CEA) identified a need and contracted the Energy & Environmental Research Center (EERC) to create and maintain an information clearinghouse on global research and development activities related to mercury emissions from coal-fired electric utilities. With the support of CEA, the Center for Air Toxic Metals{reg_sign} (CATM{reg_sign}) Affiliates, and the U.S. Department of Energy (DOE), the EERC developed comprehensive quarterly information updates that provide a detailed assessment of developments in the various areas of mercury monitoring, control, policy, and research. A total of eight topical reports were completed and are summarized and updated in this final CEA quarterly report. The original quarterly reports can be viewed at the CEA Web site (www.ceamercuryprogram.ca). In addition to a comprehensive update of previous mercury-related topics, a review of results from the CEA Mercury Program is provided. Members of Canada's coal-fired electricity generation sector (ATCO Power, EPCOR, Manitoba Hydro, New Brunswick Power, Nova Scotia Power Inc., Ontario Power Generation, SaskPower, and TransAlta) and CEA, have compiled an extensive database of information from stack-, coal-, and ash-sampling activities. Data from this effort are also available at the CEA Web site and have provided critical information for establishing and reviewing a mercury standard for Canada that is protective of environment and public health and is cost-effective. Specific goals outlined for the CEA mercury program included the following: (1) Improve emission inventories and develop management options through an intensive 2-year coal-, ash-, and stack-sampling program; (2) Promote effective stack testing through the development of guidance material and the support of on-site training on the Ontario Hydro method for employees, government representatives, and contractors on an as-needed basis; (3) Strengthen laboratory analytical capabilities through

  8. A Ferrocene-Quinoxaline Derivative as a Highly Selective Probe for Colorimetric and Redox Sensing of Toxic Mercury(II Cations

    Directory of Open Access Journals (Sweden)

    Antonio Caballero

    2010-12-01

    Full Text Available A new chemosensor molecule 3 based on a ferrocene-quinoxaline dyad recognizes mercury (II cations in acetonitrile solution. Upon recognition, an anodic shift of the ferrocene/ferrocenium oxidation peaks and a progressive red-shift (Δλ = 140 nm of the low-energy band, are observed in its absorption spectrum. This change in the absorption spectrum is accompanied by a colour change from orange to deep green, which can be used for a “naked-eye” detection of this metal cation.

  9. Toward a Unified Understanding of Mercury and Methylated Mercury from the World's Oceans

    Science.gov (United States)

    McNutt, M. K.; Krabbenhoft, D. P.; Landing, W. M.; Sunderland, E. M.

    2012-12-01

    Marine fish and shellfish are the main source of toxic methylmercury exposure for humans. As recently as decade ago, very limited aqueous methylated mercury data were available from marine settings, resulting in a generally poor understanding of the processes controlling mercury in pelagic marine food webs. Recent oceanographic cruises have significantly improved availability of reliable measurements of methylated mercury and total mercury in seawater. This presentation will focus on vertical seawater profiles collected to depths 1000 m from three recent sampling efforts in collaboration with the CLIVAR Repeat Hydrography Program sponsored by NOAA including: 1) the northeastern Pacific (P16N cruise from Honolulu, Hawaii to Kodiak, Alaska); (2) the southern Indian Ocean (I5 cruise from Cape Town, South Africa, to Fremantle, Australia); and, (3) the Southern Ocean cruise (S4P from McMurdo, Antarctica, to Punta Arenas, Chile). Analytical results presented were all derived from the USGS Mercury Research Lab (http://wi.water.usgs.gov/mercury-lab). Supporting data derived from these cruises on water mass ages, nutrients, carbon and dissolved oxygen provide an opportunity to develop a stronger understanding of the biogeochemical factors controlling oceanic distributions of mercury and methylated mercury. Whole-water, median total mercury, and methylated mercury concentrations for the northern Pacific, southern Indian, and Southern Ocean were 1.10, 0.80, and 1.65 pM, , and 0.11, 0.08, and 0.32 pM, respectively. For all three oceans, vertical profiles of total mercury generally show the lowest concentrations in the surface mixed layer, and concentration maxima at the 700-1000 m depths. Surface depletion of total mercury is attributed to photo-chemical reduction and evasion of gaseous elemental mercury as well as scavenging by settling particulate matter, the main vector of transport to the subsurface ocean. Methylated mercury in all the ocean profiles reveal distinct mid

  10. Coal fired flue gas mercury emission controls

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jiang; Pan, Weiguo [Shanghai Univ. of Electric Power (China); Cao, Yan; Pan, Weiping [Western Kentucky Univ., Bowling Green, KY (United States)

    2015-05-01

    Mercury (Hg) is one of the most toxic heavy metals, harmful to both the environment and human health. Hg is released into the atmosphere from natural and anthropogenic sources and its emission control has caused much concern. This book introduces readers to Hg pollution from natural and anthropogenic sources and systematically describes coal-fired flue gas mercury emission control in industry, especially from coal-fired power stations. Mercury emission control theory and experimental research are demonstrated, including how elemental mercury is oxidized into oxidized mercury and the effect of flue gas contents on the mercury speciation transformation process. Mercury emission control methods, such as existing APCDs (air pollution control devices) at power stations, sorbent injection, additives in coal combustion and photo-catalytic methods are introduced in detail. Lab-scale, pilot-scale and full-scale experimental studies of sorbent injection conducted by the authors are presented systematically, helping researchers and engineers to understand how this approach reduces the mercury emissions in flue gas and to apply the methods in mercury emission control at coal-fired power stations.

  11. RESISTANCE LEVEL OF Pseudomonas stutzeri AGAINST MERCURY AND ITS ABILITY IN PRODUCTION OF MERCURY REDUCTASE ENZYME

    Directory of Open Access Journals (Sweden)

    Purkan Purkan

    2016-11-01

    Full Text Available Mercury reductase is an enzyme that is able to reduce Hg2+ to Hg0 non toxic. This enzyme is usually produced by mercury resistant bacteria. The research wanted to determine the resistance of indigenous Pseudomonas stutzeri isolate toward mercury and to explore the mercury reductase activity which is produced by the bacteria. The results of resistance assay of the Pseudomonas stutzeri toward mercury ion showed that the isolate could survive in media containing HgCl2 up to a concentration of 80 µM. The bacteria could produce mercury reductase optimally at the 24th of fermentation time. The enzyme showed optimum activity at pH 7 and temperature of 45 oC

  12. Inhalants in Peru.

    Science.gov (United States)

    Lerner, R; Ferrando, D

    1995-01-01

    In Peru, the prevalence and consequences of inhalant abuse appear to be low in the general population and high among marginalized children. Inhalant use ranks third in lifetime prevalence after alcohol and tobacco. Most of the use appears to be infrequent. Among marginalized children, that is, children working in the streets but living at home or children living in the street, the problem of inhalant abuse is a serious problem. Among children working in the streets but living at home, the lifetime prevalence rate for inhalant abuse is high, ranging from 15 to 45 percent depending on the study being cited. For children living in the streets, the use of inhalant is even more severe. As mentioned earlier in this chapter, most of these street children use inhalants on a daily basis. The lack of research on the problem of inhalant abuse is a serious impediment to development of intervention programs and strategies to address this problem in Peru. Epidemiologic and ethnographic research on the nature and extent of inhalant abuse are obvious prerequisites to targeted treatment and preventive intervention programs. The urgent need for current and valid data is underscored by the unique vulnerability of the youthful population at risk and the undisputed harm that results from chronic abuse of inhalants. Nonetheless, it is important to mention several programs that work with street children. Some, such as the Information and Education Center for the Prevention of Drug Abuse, Generation, and Centro Integracion de Menores en Abandono have shelters where street children are offered transition to a less marginal lifestyle. Teams of street educators provide the children with practical solutions and gain their confidence, as well as offer them alternative socialization experiences to help them survive the streets and avoid the often repressive and counterproductive environments typical of many institutions. Most of the children who go through these programs tend to abandon

  13. MERCURY STABILITY IN THE ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    John H. Pavlish

    1999-07-01

    The 1990 Clean Air Act Amendments (CAAAs) require the U.S. Environmental Protection Agency (EPA) to determine whether the presence of mercury and 188 other trace substances, referred to as air toxics or hazardous air pollutants (HAPs), in the stack emissions from fossil fuel-fired electric utility power plants poses an unacceptable public health risk (1). The EPA's conclusions and recommendations were presented in two reports: Mercury Study Report to Congress and Study of Hazardous Air Pollutant Emissions from Electric Utility Steam Generating Units-Final Report to Congress. The first congressional report addressed both human health and the environmental effects of anthropogenic mercury emissions, while the second report addressed the risk to public health posed by emissions of HAPs from steam electricity-generating units. The National Institute of Environmental Health Sciences is also required by the CAAAs to investigate mercury and determine a safe threshold level of exposure. Recently the National Academy of Sciences has also been commissioned by Congress to complete a report, based the available scientific evidence, regarding safe threshold levels of mercury exposure. Although the EPA reports did not state that mercury controls on coal-fired electric power stations should be required given the current state of the art, they did indicate that EPA views mercury as a potential threat to human health. It is likely that major sources of mercury emissions, including fossil-fired combustion systems, will be controlled at some point. In fact, municipal waste combustion units are already regulated. In anticipation of additional control measures, much research has been done (and continues) regarding the development of control technologies for mercury emitted from stationary sources to the atmosphere. Most approaches taken to date involve sorbent injection technologies or improve upon removal of mercury using existing technologies such as flue gas desulfurization

  14. The Toxicity of Inhaled Sulphur Mustard

    Science.gov (United States)

    2012-10-01

    Intubation of these animals with HD exposure direct to the lung via the endotracheal (ET) tube better represents human exposure via the nose and... endotracheal (ET) tube which had been lined with polytetrafluoroethylene (PTFE) as previously described [4]. Where intubation was not viable due to...HD exposure. Intubation of these animals and exposure directly via the endotracheal (ET) tube better represents human exposure via the nose and mouth

  15. Chronic Inhalation Toxicity of Hydrazine: Oncogenic Effects

    Science.gov (United States)

    1981-06-01

    showed signs of anorexia and general fatigue. Changing diets and forced feedings resulted in the survival of the remaining two dogs. A 6-month chronic...Esophagus Bladder Stomach Seminal vesicles Duodenum Prostate Jejunum Testes Ileum Ovaries Cecum Uterus Colon Nasal cavity Rectum Brain Mesenteric lymph... malnutrition during chronic exposure. Based upon these studies, the current OSHA Threshold Limit Value of 1.0 ppm for hydrazine is unsatisfactory while the

  16. Prolonged asthma after smoke inhalation: A report of three cases and a review of previous reports

    Energy Technology Data Exchange (ETDEWEB)

    Moisan, T.C. (Department of Preventive Medicine, Loyola University-Stritch School of Medicine, Maywood, IL (USA))

    1991-04-01

    The development of prolonged obstructive airways disease after smoke inhalation is of concern to fire victims and fire fighters. Three cases of asthma that developed following the inhalation of pyrolysis products are presented along with a review of previous reports of airway injury from smoke inhalation. Polyvinyl chloride pyrolysis products seem to pose a high risk, but other toxic inhalants are also implicated. There is substantial evidence that prolonged airway hyper-responsiveness and asthma may follow numerous inflammatory insults including smoke inhalation. Studies to identify specific individual risk factors and asthmagenic pyrolysis products are needed. Early, postexposure anti-inflammatory treatment may modify the outcome. 42 refs.

  17. Mercury in municipal solid wastes and New Jersey mercury prevention and reduction program

    Energy Technology Data Exchange (ETDEWEB)

    Erdogan, H.; Stevenson, E. [New Jersey Department of Environmental Protection, Trenton, NJ (United States). Division of Science and Research

    1994-12-31

    Mercury is a very toxic heavy metal which accumulates in the brain causing neurological damages involving psychasthenic and vegetative syndrome. At high exposure levels it causes behavioral and personality changes, loss of memory and insomnia. Long-term exposure or exposure during pregnancy to mercury or mercury compounds can permanently damage the kidney and fetus. In addition to potential effects on human health, mercury poisoning can also affect other living organisms. Mercury is different than other heavy metals. It consistently biomagnifies and bioaccumulates within the aquatic food chain. Global sources of mercury release are both natural and anthropogenic. Natural sources include volatilization of gaseous-mercury iron soils ana rocks, volcanic releases, evaporation from the ocean and other water bodies. Anthropogenic sources are fuel and coal combustion, mining, smelting, manufacturing activities, disposal of sludge, pesticides, animal and food waste, and incineration of municipal solid waste. Worldwide combustion of municipal solid waste is the second largest source of atmospheric emission of mercury. In New Jersey, incineration of solid waste is the largest source of atmospheric emission of mercury. The New Jersey Department of Environmental Protection and Energy (NJDEPE) has developed a comprehensive program to control and prevent emission of mercury resulting from combustion municipal solid waste.

  18. The tropical African mercury anomaly: lower than expected mercury concentrations in fish and human hair.

    Science.gov (United States)

    Black, Frank J; Bokhutlo, Thethela; Somoxa, Aaron; Maethamako, Mothusi; Modisaemang, Ontlogetse; Kemosedile, Thebe; Cobb-Adams, Cristina; Mosepele, Ketlhatlogile; Chimbari, Moses

    2011-04-15

    Mercury is a neurotoxin and global pollutant, and wetlands and newly flooded areas are known to be sites of enhanced production of monomethylmercury, the form of mercury that is readily biomagnified in aquatic food chains to potentially toxic levels. The Okavango Delta in Botswana, Southern Africa, is the largest inland delta in the world and a wetland ecosystem that experiences dramatic annual flooding of large tracts of seasonal floodplains. The Delta was, therefore, expected to be home to high mercury levels in fish and to be an area where local subsistence fishing communities would be at substantial risk of mercury toxicity from fish consumption. Total mercury concentrations measured in 27 species of fish from the Okavango Delta averaged (mean±s.d., wet weight) 19±19ng g(-1) in non-piscivorous fish, and 59±53ng g(-1) in piscivorous fish. These mercury concentrations are similar to those reported for fish from lakes in other areas of tropical Africa, demonstrating that not all wetlands are sites of elevated mercury concentrations in biota. Even more intriguing is that concentrations of mercury in fish from across tropical Africa are systematically and substantially lower than those typically reported for fish from freshwater ecosystems elsewhere globally. The reasons for this apparent "African mercury anomaly" are unclear, but this finding poses a unique opportunity to improve our understanding of mercury's biogeochemical cycling in the environment. Mercury concentrations measured in human hair collected in subsistence fishing communities in the Okavango Delta were similarly low (0.21±0.22μg g(-1) dry weight) despite high levels of fish consumption, and reflect the low mercury concentrations in the fish here.

  19. A new cutaneous sign of mercury poisoning?

    Science.gov (United States)

    Dantzig, Paul I

    2003-12-01

    Chronic mercury poisoning is becoming a health concern because of extensive pollution of water and fish, and the increasing consumption of fish in the human diet. Mercury is extremely toxic to the body, especially the central nervous system, but diagnosis is difficult because of the lack of specific signs. A total of 11 patients were observed to have a nonpruritic or mildly pruritic discreet papular and papulovesicular eruption that correlated with high blood mercury levels. The mercury evidently came from increased seafood consumption. All of the patients improved when they were placed on either a seafood-free diet or chelation therapy. Physicians should suspect mercury poisoning in patients who eat a high-seafood diet who present with an asymptomatic or mildly pruritic papular or papulovesicular eruption.

  20. [Ventricular fibrillation following deodorant spray inhalation].

    Science.gov (United States)

    Girard, F; Le Tacon, S; Maria, M; Pierrard, O; Monin, P

    2008-01-01

    We report one case of out-of-hospital cardiac arrest with ventricular fibrillation following butane poisoning after inhalation of antiperspiration aerosol. An early management using semi-automatic defibrillator explained the success of the resuscitation. The mechanism of butane toxicity could be an increased sensitivity of cardiac receptors to circulating catecholamines, responsible for cardiac arrest during exercise and for resuscitation difficulties. The indication of epinephrine is discussed.

  1. Acute myocardial involvement after heroin inhalation

    Directory of Open Access Journals (Sweden)

    Ritu Karoli

    2012-01-01

    Full Text Available Amongst the illicit drugs cocaine, amphetamines and cannabis have been studied and documented well to cause myocardial infarction by different mechanisms but there is very sparse data available on myocardial involvement after heroin abuse. We report a young man who developed acute myocardial injury after heroin inhalation and alcohol binge drinking. Heroin induced cardio toxic effect and vasospasm compounded by alcohol were suspected to be the cause of this.

  2. Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Comprehensive progress report, October 1, 1975--December 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, R. H.

    1978-10-01

    Investigations were undertaken to elucidate the mode of transepithelial transport of potentially toxic metal ions across the gastrointestinal tract, with primary attention given to cadmium, zinc, and arsenic. In addition, the toxic effects of cadmium on the metabolism of vitamin D and calcium have been investigated in some detail. Several approaches have been taken, including studies on the localization of heavy metals in the intestinal mucosa, the effects of cadmium on various parameters of calcium metabolism, the modes of intestinal absorption of cadmium, arsenate, and zinc, and the interactions of heavy metals with each other and with calcium, phosphorus, and vitamin D. Details of these experiments are attached in the Comprehensive Progress Report.

  3. Avian mercury exposure and toxicological risk across western North America: A synthesis

    Science.gov (United States)

    Ackerman, Josh; Eagles-Smith, Collin A.; Herzog, Mark; Hartman, Christopher; Peterson, Sarah; Evers, David C.; Jackson, Allyson K.; Elliott, John E.; Vander Pol, Stacy S.; Bryan, Colleen E.

    2016-01-01

    Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 original bird mercury concentrations from 225 species were compiled, and an additional 1712 mean mercury concentrations, representing 19998 individuals and 176 species, from 200 publications were obtained. To make mercury data comparable across bird tissues, published equations of tissue mercury correlations were used to convert all mercury concentrations into blood-equivalent mercury concentrations. Blood-equivalent mercury concentrations differed among species, foraging guilds, habitat types, locations, and ecoregions. Piscivores and carnivores exhibited the greatest mercury concentrations, whereas herbivores and granivores exhibited the lowest mercury concentrations. Bird mercury concentrations were greatest in ocean and salt marsh habitats and lowest in terrestrial habitats. Bird mercury concentrations were above toxicity benchmarks in many areas throughout western North America, and multiple hotspots were identified. Additionally, published toxicity benchmarks established in multiple tissues were summarized and translated into a common blood-equivalent mercury concentration. Overall, 66% of birds sampled in western North American exceeded a blood-equivalent mercury concentration of 0.2 μg/g wet weight (ww; above background levels), which is the lowest-observed effect level, 28% exceeded 1.0 μg/g ww (moderate risk), 8% exceeded 3.0 μg/g ww (high risk), and 4% exceeded 4.0 μg/g ww (severe risk). Mercury monitoring programs should sample bird tissues, such as adult blood and eggs, that are most-easily translated into tissues with well-developed toxicity benchmarks and that

  4. Hepatotoxic Alterations Induced by Inhalation of Trichloroethylene (TCE) in Rats

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective Trichloroethylene (TCE) is one of the most potent organic unsaturated solvents being used in dry cleaning, metal degreasing, thinner for paints varnishes and electroplating, etc. and has been reported to be a hepatotoxicant through oral and dermal exposure. However, its inhalation toxicity data is very limited in the literature due to the fact that the exposure levels associated with these effects were usually not reported. Hence, inhalation toxicity study was carried out for hepatotoxic studies. Method Inhalation toxicity studies was carried out by exposing rats to TCE for 8, 12 and 24 weeks in a dynamically operated whole body inhalation chamber. Sham treated control rats were exposed to compressed air in the inhalation chamber for the same period. Results Significant increase in liver weight (liver enlargement) appearance of necrotic lesions with fatty changes and marked necrosis were observed after longer duration (12 and 24 weeks) of TCE exposure. The lysosomal rupture resulted in increased activity of acid and alkaline phosphatase alongwith reduced glutathione content and total increased sulfhydryl content in liver tissue. Conclusion TCE exposure through Inhalation route induces hepatotoxicity in terms of marked necrosis with fatty changes and by modulating the lysosomal enzymes.

  5. Mercury in Morelet's crocodile eggs from northern Belize.

    Science.gov (United States)

    Rainwater, T R; Adair, B M; Platt, S G; Anderson, T A; Cobb, G P; McMurry, S T

    2002-04-01

    Recent studies have examined mercury accumulation in crocodilians. However, though most researchers have focused on tissue concentrations, few have examined mercury levels in crocodilian eggs. In July 1995, we analyzed mercury in 31 nonviable Morelet's crocodile ( Crocodylus moreletii) eggs collected from eight nests across three localities in northern Belize. All eggs were found to contain mercury. Based on an individual egg basis, mean concentration of mercury for all three localities was among the lowest reported for any crocodilian species. When localities were examined separately, mean concentrations for Laguna Seca and Gold Button Lagoon were comparable to those observed in other studies, and the mean for Sapote Lagoon was the lowest ever reported. Based on mean nest concentrations, mercury in eggs from Laguna Seca was approximately two- and tenfold higher than for Gold Button Lagoon and Sapote Lagoon, respectively. Variability in mercury concentrations among localities is likely the result of site-specific differences in mercury input, bioavailabilty, and bioaccumulation. Mercury concentrations were relatively uniform in eggs from the same nest and among nests from the same localities. The presence of mercury in Morelet's crocodile eggs suggests exposure in adult females, developing embryos, and neonates. However, crocodiles in these areas show no overt signs of mercury toxicity, and no indication of population decline is evident. A paucity of data on the effects of mercury on crocodilians precludes meaningful speculation as to the biological significance of tissue and egg concentrations. Controlled laboratory studies and long-term population monitoring are needed to address these questions.

  6. Formoterol Oral Inhalation

    Science.gov (United States)

    ... of lung diseases that includes chronic bronchitis and emphysema) in adults. Formoterol inhalation powder is also used with another medication to treat asthma and to prevent breathing difficulties during exercise in ...

  7. Indacaterol Oral Inhalation

    Science.gov (United States)

    Indacaterol inhalation is used to control wheezing, shortness of breath, coughing, and chest tightness caused by chronic obstructive pulmonary disease (COPD). Indacaterol is in a class of medications called long- ...

  8. Pentamidine Oral Inhalation

    Science.gov (United States)

    Pentamidine is an anti-infective agent that helps to treat or prevent pneumonia caused by the organism ... Pentamidine comes as a solution to be inhaled using a nebulizer. It usually is used once every ...

  9. Insulin Human Inhalation

    Science.gov (United States)

    Insulin inhalation is used in combination with a long-acting insulin to treat type 1 diabetes (condition in which the body does not produce insulin and therefore cannot control the amount of sugar ...

  10. Biotoxicity of mercury as influenced by mercury(II) speciation.

    Science.gov (United States)

    Farrell, R E; Germida, J J; Huang, P M

    1990-10-01

    Integration of physicochemical procedures for studying mercury(II) speciation with microbiological procedures for studying the effects of mercury on bacterial growth allows evaluation of ionic factors (e.g., pH and ligand species and concentration) which affect biotoxicity. A Pseudomonas fluorescens strain capable of methylating inorganic Hg(II) was isolated from sediment samples collected at Buffalo Pound Lake in Saskatchewan, Canada. The effect of pH and ligand species on the toxic response (i.e., 50% inhibitory concentration [IC50]) of the P. fluorescens isolated to mercury were determined and related to the aqueous speciation of Hg(II). It was determined that the toxicities of different mercury salts were influenced by the nature of the co-ion. At a given pH level, mercuric acetate and mercuric nitrate yielded essentially the same IC50s; mercuric chloride, on the other hand, always produced lower IC50s. For each Hg salt, toxicity was greatest at pH 6.0 and decreased significantly (P = 0.05) at pH 7.0. Increasing the pH to 8.0 had no effect on the toxicity of mercuric acetate or mercuric nitrate but significantly (P = 0.05) reduced the toxicity of mercuric chloride. The aqueous speciation of Hg(II) in the synthetic growth medium M-IIY (a minimal salts medium amended to contain 0.1% yeast extract and 0.1% glycerol) was calculated by using the computer program GEOCHEM-PC with a modified data base. Results of the speciation calculations indicated that complexes of Hg(II) with histidine [Hg(H-HIS)HIS+ and Hg(H-HIS)2(2+)], chloride (HgCl+, HgCl2(0), HgClOH0, and HgCl3-), phosphate (HgHPO4(0), ammonia (HgNH3(2+), glycine [Hg(GLY)+], alanine [Hg(ALA)+], and hydroxyl ion (HgOH+) were the Hg species primarily responsible for toxicity in the M-IIY medium. The toxicity of mercuric nitrate at pH 8.0 was unaffected by the addition of citrate, enhanced by the addition of chloride, and reduced by the addition of cysteine. In the chloride-amended system, HgCl+, HgCl2(0), and Hg

  11. Mercury uptake and accumulation by four species of aquatic plants

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Kathleen [Department of Biology, Russell Sage College, 45 Ferry Street, Troy, NY 12180 (United States)]. E-mail: skinnk@sage.edu; Wright, Nicole [NEIWPCC-NYSDEC, 625 Broadway, 4th Floor, Albany, NY 12233-3502 (United States)]. E-mail: ndwright@gw.dec.state.ny.us; Porter-Goff, Emily [Department of Biology, Russell Sage College, 45 Ferry Street, Troy, NY 12180 (United States)

    2007-01-15

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox[reg] (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox[reg] results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. - Four species of aquatic plants reduced mercury in water.

  12. Mercury recycling in the United States in 2000

    Science.gov (United States)

    Brooks, William E.; Matos, Grecia R.

    2005-01-01

    Reclamation and recycling of mercury from used mercury- containing products and treatment of byproduct mercury from gold mining is vital to the continued, though declining, use of this metal. Mercury is reclaimed from mercury-containing waste by treatment in multistep high-temperature retorts-the mercury is volatized and then condensed for purification and sale. Some mercury-containing waste, however, may be landfilled, and landfilled material represents loss of a recyclable resource and a threat to the environment. Related issues include mercury disposal and waste management, toxicity and human health, and regulation of mercury releases in the environment. End-users of mercury-containing products may face fines and prosecution if these products are improperly recycled or not recycled. Local and State environmental regulations require adherence to the Resource Conservation and Recovery Act and the Comprehensive Environmental Response, Compensation, and Liability Act to regulate generation, treatment, and disposal of mercury-containing products. In the United States, several large companies and a number of smaller companies collect these products from a variety of sources and then reclaim and recycle the mercury. Because mercury has not been mined as a principal product in the United States since 1992, mercury reclamation from fabricated products has become the main source of mercury. Principal product mercury and byproduct mercury from mining operations are considered to be primary materials. Mercury may also be obtained as a byproduct from domestic or foreign gold-processing operations. In the early 1990s, U.S. manufacturers used an annual average that ranged from 500 to 600 metric tons of recycled and imported mercury for fabrication of automobile convenience switches, dental amalgam, fluorescent lamps, medical uses and thermometers, and thermostats. The amount now used for fabrication is estimated to be 200 metric tons per year or less. Much of the data on

  13. Environmental impact of toxic metals and metalloids from the Muñón Cimero mercury-mining area (Asturias, Spain).

    Science.gov (United States)

    Loredo, Jorge; Ordóñez, Almudena; Alvarez, Rodrigo

    2006-08-25

    This paper presents the results of the sampling surveys carried out in order to evaluate the environmental problems associated to La Soterraña, an abandoned Hg mine in Asturias, north of Spain. In particular, this paper overviews the impact of mining and metallurgical activities on terrestrial and aquatic environments. The wastes generated during the mining activity (ore extraction and processing) and later accumulated on the ground, contain great amount of sulphides, becoming potentially acid-generating. Consequently, the mobility of heavy metals and other ecotoxic elements is enhanced. Wastes are generally located close to watercourses and on very steep hillsides, where they are exposed to oxidative weathering, posing a significant risk due to the release of ecotoxic elements to the environment. Background levels were determined at sites, which had not been directly affected by mercury mining. A multielemental geochemical study of mining wastes, soils, stream sediments, water and air samples collected in the area of influence of the old mining and metallurgical works was carried out. Total Hg and As concentrations in soils reach values up to 502 and 19,940 mg kg(-1), respectively, 500 and 2000 times higher than the local background levels. The effects of mining seem to be intense both in waters and stream sediments, as well as in the local atmosphere, whose Hg content is 10 times higher than the background level in the area. Therefore, the target carcinogenic risk was exceeded for As and Hg in La Soterraña site.

  14. Testicular toxicity induced by inhalation exposure to 1-bromopropane in Wistar rats%1-溴丙烷吸入染毒对Wistar大鼠睾丸毒性研究

    Institute of Scientific and Technical Information of China (English)

    罗巧; 宋向荣; 李宏玲; 刘浩中; 赵娜; 王海兰

    2015-01-01

    Objective To explore the effects of 1-bromopropane (1-BP) inhalation exposure on the testicular structure and the expression of B-cell lymphoma-2 gene (Bcl-2) and Bcl-2 associated X protein (Bax).Methods Twenty-four specific pathogen free healthy male Wistar rats were randomly divided into control group and exposure group, and then separately exposed to 1-BP vapor for 4 weeks (8 h/day, 5 days/week) at the concentrations of 0.00 and 5 000.00 mg/m3 in a dynamic inhalation chamber system.After exposure, the rats’ main organs were dissected and weighed and the organ coefficients were calculated.Histopathologic changes of testis were observed by microscopy, testicular slices were scanned by pathological slice scanner, and quantitative analysis was carried out to measure the average diameter of testicular seminiferous tubule and the proportion of seminiferous tubules containing the sperm.The expressions of Bcl-2 and Bax protein in testicular were determined by immunohistochemical method.Results Compared with the control group, the body weight from the 1st to the 4th week was significantly decreased in the exposure group (P0.05]. The structures of most of the testicular seminiferous tubules were normal in the exposure group, but individual pieces of testicular seminiferous tubules showed obvious morphological changes.The significant difference was not found in average diameter of testicular seminiferous tubule between the exposure and control groups [ ( 279.88 ±15.49 ) vs ( 285.41 ± 12.69) μm;P>0.05].Compared with the control group, the proportion of seminiferous tubules containing the sperm in the testis was significantly decreased in the exposure group [(42.00 ±10.79) %vs (56.05 ±12.72)%;P0.05 ) . Conclusion The inhalation exposure to 1-BP may induce injury of testis in male Wistar rats.The enhancing expression of Bax protein in testis may play a role in the mechanism of testicular toxicity.%目的:探讨1-溴丙烷吸入染毒对Wistar大鼠睾

  15. Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc and copper. Progress report, January 1, 1980-December 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, R H

    1980-01-01

    Investigations were continued to elucidate the mode of transepithelial transport of toxic metal ions across the gastrointestinal tract, as well as their interactions with biological processes and other metal ions. All experimental details that are either published, submitted for publication or in press during this report period are included in the Appendix. Primary attention for this report has been given to the intestinal absorption of lead and its interaction with other biological moieties.

  16. Study on the subacute inhalation toxicity of ivermectin TC in rats%伊维菌素原药对大鼠的亚急性吸入毒性研究

    Institute of Scientific and Technical Information of China (English)

    纪磊; 岑江杰; 林师道; 胡成云; 方华; 徐剑; 陈杰

    2016-01-01

    Objective To study the subacute inhalation toxicity of Ivermectin TC, and obtain its non-observed adverse effect level(NOAEL).Methods It was performed on the doses of Ivermectin TC 190, 380, 750 mg/m3, the solvent control group (0.03%Tween-80 solution) , the control group and additional group ( there were 6 female and 6 male Sprague-Dawley rats for each group) .The animals inhaled with nose-only exposure for 4 weeks (4 h/d, 5 d/week) .The additional group should be observed another 14 days after exposing.At the end of experiment, the rats were killed, the routine and biochemical detection, the body weight and organ to body weight ratios were all measured.Results In the high exposure group, clinical signs of rats included hair fluffy, dull, salivation, tremors were recorded at the exposure period;in female rats, feed efficiency was decreased, ALT and liver to body weight ratio were increased; in male rats, BUN and ALT were increased, CHOL and body weight for the 4th week were decreased.Histopathological examinations revealed that swelling in the liver cell was seen in some female rats at high exposure group.Conclusion The results suggested that the NOAEL of Ivermectin TC in SD rats was 380 mg/m3(4 h/d for 28 days).%目的 研究伊维菌素原药对大鼠亚急性吸入毒性,求出最大无作用剂量.方法 采用SPF级Sprague-Dawley(SD)大鼠,共72只,随机分成6组,每组12只,雌雄各半.设190、380、750 mg/m3等3个剂量组和1个溶剂对照组(0.03%吐温-80溶液),另设1个空白对照和1个附加组(750 mg/m3).采用动式(口鼻式)吸入染毒,每天染毒1次,持续4 h,每周染毒5 d,直至28 d,附加组动物停止染毒后继续观察14 d.试验结束后,分别对动物作血液常规、生化、体重及脏器系数等测定,并进行组织病理学检查.结果 750 mg/m3剂量组雌雄大鼠在染毒后期出现被毛蓬松、呆滞、流涎、震颤等中毒反应.750 mg/m3剂量组雌鼠食物利用率下降,血清丙氨酸氨

  17. Chelation Therapy for Mercury Poisoning

    OpenAIRE

    Rong Guan; Han Dai

    2009-01-01

    Chelation therapy has been the major treatment for heavy metal poisoning. Various chelating agents have been developed and tested for treatment of heavy metal intoxications, including mercury poisoning. It has been clearly shown that chelating agents could rescue the toxicity caused by heavy metal intoxication, but the potential preventive role of chelating agents against heavy metal poisoning has not been explored much. Recent paper by Siddiqi and colleagues has suggested a protective role o...

  18. The effect of mercury on trees and their mycorrhizal fungi

    Energy Technology Data Exchange (ETDEWEB)

    Jean-Philippe, Sharon R., E-mail: jeanphil@utk.edu [University of Tennessee, Department of Forestry, Wildlife and Fisheries, 274 Ellington Plant Science Building, 2431 Joe Johnson Dr., Knoxville, TN 37996-4563 (United States); Franklin, Jennifer A., E-mail: jafranklin@utk.edu [University of Tennessee, Department of Forestry, Wildlife and Fisheries, 274 Ellington Plant Science Building, 2431 Joe Johnson Dr., Knoxville, TN 37996-4563 (United States); Buckley, David S., E-mail: dbuckley@utk.edu [University of Tennessee, Department of Forestry, Wildlife and Fisheries, 274 Ellington Plant Science Building, 2431 Joe Johnson Dr., Knoxville, TN 37996-4563 (United States); Hughes, Karen, E-mail: khughes@utk.edu [University of Tennessee, Ecology and Evolutionary Biology, 350 Hesler Biology Building and Greenhouse, 1406 Circle Drive, Knoxville, TN 37996-1610 (United States)

    2011-10-15

    The Oak Ridge Reservation, established in 1942, was the designated site for the construction of the atomic bomb. During a 20-year period from 1944 to 1963 radioactive and toxic chemical pollutants, especially mercury compounds were released into the surrounding waterways. Tree diversity and mycorrhizal presence and abundance were analyzed in the mercury-contaminated floodplains of East Fork Poplar Creek Oak Ridge (EFPC) (Tennessee). A subsequent greenhouse study was conducted to assess the phytotoxic effects of different mercuric solutions on Platanus occidentalis (American Sycamore), inoculated with soils from EFPC. Total soil mercury in the field had no effect on tree diversity. Organic species of mercury proved to be more toxic than inorganic species of mercury and soil inoculants from EFPC had no protective effects against Hg toxicity in our greenhouse study. Comparison of the effects of mercury contamination in our field and greenhouse studies was difficult due to uncontrolled factors. - Highlights: > Heavy metals effects on ecosystems may be difficult to pinpoint in the field. > Toxic effects of mercury depend on its chemical form and concentration. > Mycorrhizae have been shown to be increase heavy metal tolerance in host plant. - Though evidence suggests that mercury-contaminated soils may reduce tree and fungal populations, there are tolerant species that may remain and survive following contamination.

  19. Maternal transfer of mercury to songbird eggs

    Science.gov (United States)

    Ackerman, Josh; Hartman, C. Alex; Herzog, Mark

    2017-01-01

    We evaluated the maternal transfer of mercury to eggs in songbirds, determined whether this relationship differed between songbird species, and developed equations for predicting mercury concentrations in eggs from maternal blood. We sampled blood and feathers from 44 house wren (Troglodytes aedon) and 34 tree swallow (Tachycineta bicolor) mothers and collected their full clutches (n = 476 eggs) within 3 days of clutch completion. Additionally, we sampled blood and feathers from 53 tree swallow mothers and randomly collected one egg from their clutches (n = 53 eggs) during mid to late incubation (6–10 days incubated) to evaluate whether the relationship varied with the timing of sampling the mother's blood. Mercury concentrations in eggs were positively correlated with mercury concentrations in maternal blood sampled at (1) the time of clutch completion for both house wrens (R2 = 0.97) and tree swallows (R2 = 0.97) and (2) during mid to late incubation for tree swallows (R2 = 0.71). The relationship between mercury concentrations in eggs and maternal blood did not differ with the stage of incubation when maternal blood was sampled. Importantly, the proportion of mercury transferred from mothers to their eggs decreased substantially with increasing blood mercury concentrations in tree swallows, but increased slightly with increasing blood mercury concentrations in house wrens. Additionally, the proportion of mercury transferred to eggs at the same maternal blood mercury concentration differed between species. Specifically, tree swallow mothers transferred 17%–107% more mercury to their eggs than house wren mothers over the observed mercury concentrations in maternal blood (0.15–1.92 μg/g ww). In contrast, mercury concentrations in eggs were not correlated with those in maternal feathers and, likewise, mercury concentrations in maternal blood were not correlated with those in feathers (all R2 mercury concentrations from maternal blood to eggs (and

  20. Effects of selenite and chelating agents on mammalian thioredoxin reductase inhibited by mercury: implications for treatment of mercury poisoning.

    Science.gov (United States)

    Carvalho, Cristina M L; Lu, Jun; Zhang, Xu; Arnér, Elias S J; Holmgren, Arne

    2011-01-01

    Mercury toxicity is a highly interesting topic in biomedicine due to the severe endpoints and treatment limitations. Selenite serves as an antagonist of mercury toxicity, but the molecular mechanism of detoxification is not clear. Inhibition of the selenoenzyme thioredoxin reductase (TrxR) is a suggested mechanism of toxicity. Here, we demonstrated enhanced inhibition of activity by inorganic and organic mercury compounds in NADPH-reduced TrxR, consistent with binding of mercury also to the active site selenolthiol. On treatment with 5 μM selenite and NADPH, TrxR inactivated by HgCl(2) displayed almost full recovery of activity. Structural analysis indicated that mercury was complexed with TrxR, but enzyme-generated selenide removed mercury as mercury selenide, regenerating the active site selenocysteine and cysteine residues required for activity. The antagonistic effects on TrxR inhibition were extended to endogenous antioxidants, such as GSH, and clinically used exogenous chelating agents BAL, DMPS, DMSA, and α-lipoic acid. Consistent with the in vitro results, recovery of TrxR activity and cell viability by selenite was observed in HgCl(2)-treated HEK 293 cells. These results stress the role of TrxR as a target of mercurials and provide the mechanism of selenite as a detoxification agent for mercury poisoning.

  1. Mercury in the environment : a primer

    Energy Technology Data Exchange (ETDEWEB)

    Lourie, B.; Glenn, W. (ed.); Ogilvie, K.; Everhardus, E.; Friesen, K.; Rae, S.

    2003-06-01

    This report provides an overview of the occurrence and effects of mercury in the environment and its impacts on human health. Low levels of mercury occur naturally everywhere in the environment in plants, animals, rocks and air. Incidental emissions occur when natural mercury is released to the environment through human activity. In Canada, coal burning and metal processing are the two largest point sources of atmospheric mercury emissions. Energy facilities have the option to invest in expensive control technologies for coal plants, or they can generate electricity from alternative energy sources. Energy conservation, however, offers the greatest overall benefits for the environment and the public. Mercury can also be released when products containing mercury (such as electrical switches, thermostats, dental amalgam, and thermometers) are broken while in use, or when they are crushed in garbage trucks and dumped in landfills. Source separation is the best way to reduce waste-related emissions. Once mercury is released to the natural environment, it can be transported long distances through air or watercourses. It is volatile, therefore evaporates readily to the atmosphere where it may do one of three things: it may fall out near the point where it was emitted; it may be transported long distances to some point downwind; or, it may enter the global atmospheric mercury pool where it will circle the globe for a year or more within the Earth's major weather systems before being deposited. Data from Canada's National Pollutant Release Inventory indicates that mercury releases and transfers total 28,674 kg per year. The most critical component of the mercury cycle is the conversion of inorganic forms of mercury to the organic compound methylmercury which is more toxic to humans. Most concern about mercury focuses on lakes and other aquatic ecosystems. Fish in hydroelectric reservoirs have been found to contain elevated methylmercury levels because natural

  2. Behavioral changes in mice following benzene inhalation.

    Science.gov (United States)

    Evans, H L; Dempster, A M; Snyder, C A

    1981-01-01

    Although benzene is an important occupational health hazard and a carcinogen, the possibility that behavioral changes may forewarn of the later-occurring hematological changes has not been investigated. A time-sampling protocol was used to quantify the occurrence of 7 categories of behavior in the homecage following daily 6-hr exposures to two strains of adult mice (CD1 and C57BL/6J). The behavioral categories were stereotypic behavior, sleeping, resting, eating, grooming, locomotion, and fighting. The inhalation exposures were designed to reflect occupational exposure. Dynamic vapor exposure techniques in standard inhalation chambers were employed. Exposure to 300 or 900 ppm benzene increased the occurrence of eating and grooming and reduced the number of mice that were sleeping or resting. The responses to benzene of both the CD1 and the C57 strains were similar. The positive findings with benzene inhalation indicate the utility of behavioral investigations into the toxicology of inhaled organic solvents. The methods described herein illustrate an objective observation of animal behavior that is capable of documenting toxicity and of guiding detailed follow-up studies aimed at mechanism of action.

  3. Nanomaterial-based approaches for the detection and speciation of mercury.

    Science.gov (United States)

    Xu, Xiaohan; Li, Yu-Feng; Zhao, Jiating; Li, Yunyun; Lin, Jing; Li, Bai; Gao, Yuxi; Chen, Chunying

    2015-12-07

    Mercury is toxic with widespread contamination. Highly sensitive and selective approaches for mercury analysis are desired. Although conventional techniques are accurate and sensitive in the determination of mercury, these procedures are time-consuming, labor-intensive and dependent heavily on expensive instrumentation. In recent years, nanomaterial-based approaches have been proved to be effective alternatives in the detection and speciation of mercury. In this review, the development of different nanomaterial-based approaches was summarized, as well as their utilization for the detection of mercury in environmental and biological samples, such as gold nanomaterials, carbon nanomaterials, quantum dots and so on. Moreover, the speciation of mercury using nanomaterials was also reviewed.

  4. Mercury Inhibits Soil Enzyme Activity in a Lower Concentration than the Guideline Value.

    Science.gov (United States)

    Mahbub, Khandaker Rayhan; Krishnan, Kannan; Megharaj, Mallavarapu; Naidu, Ravi

    2016-01-01

    Three soil types - neutral, alkaline and acidic were experimentally contaminated with nine different concentrations of inorganic mercury (0, 5, 10, 50, 100, 150, 200, 250, 300 mg/kg) to derive effective concentrations of mercury that exert toxicity on soil quality. Bioavailability of mercury in terms of water solubility was lower in acidic soil with higher organic carbon. Dehydrogenase enzyme activity and nitrification rate were chosen as indicators to assess soil quality. Inorganic mercury significantly inhibited (p mercury contents (EC10) were found to be less than the available safe limits for inorganic mercury which demonstrated inadequacy of existing guideline values.

  5. Comparative toxicogenomic responses of mercuric and methyl-mercury.

    Science.gov (United States)

    McElwee, Matthew K; Ho, Lindsey A; Chou, Jeff W; Smith, Marjolein V; Freedman, Jonathan H

    2013-10-11

    Mercury is a ubiquitous environmental toxicant that exists in multiple chemical forms. A paucity of information exists regarding the differences or similarities by which different mercurials act at the molecular level. Transcriptomes of mixed-stage C. elegans following equitoxic sub-, low- and high-toxicity exposures to inorganic mercuric chloride (HgCl2) and organic methylmercury chloride (MeHgCl) were analyzed. In C. elegans, the mercurials had highly different effects on transcription, with MeHgCl affecting the expression of significantly more genes than HgCl2. Bioinformatics analysis indicated that inorganic and organic mercurials affected different biological processes. RNAi identified 18 genes that were important in C. elegans response to mercurial exposure, although only two of these genes responded to both mercurials. To determine if the responses observed in C. elegans were evolutionarily conserved, the two mercurials were investigated in human neuroblastoma (SK-N-SH), hepatocellular carcinoma (HepG2) and embryonic kidney (HEK293) cells. The human homologs of the affected C. elegans genes were then used to test the effects on gene expression and cell viability after using siRNA during HgCl2 and MeHgCl exposure. As was observed with C. elegans, exposure to the HgCl2 and MeHgCl had different effects on gene expression, and different genes were important in the cellular response to the two mercurials. These results suggest that, contrary to previous reports, inorganic and organic mercurials have different mechanisms of toxicity. The two mercurials induced disparate effects on gene expression, and different genes were important in protecting the organism from mercurial toxicity.

  6. Know How to Use Your Asthma Inhaler

    Medline Plus

    Full Text Available ... 260 KB] Using a metered dose inhaler (inhaler in mouth) Your browser does not support iframes Using a metered dose inhaler (inhaler in mouth) [PDF - 370 KB] Your browser does not ...

  7. Current approaches of the management of mercury poisoning: need of the hour

    OpenAIRE

    Rafati-Rahimzadeh, Mehrdad; Rafati-Rahimzadeh, Mehravar; Kazemi, Sohrab; Moghadamnia, Ali Akbar

    2014-01-01

    Mercury poisoning cases have been reported in many parts of the world, resulting in many deaths every year. Mercury compounds are classified in different chemical types such as elemental, inorganic and organic forms. Long term exposure to mercury compounds from different sources e.g. water, food, soil and air lead to toxic effects on cardiovascular, pulmonary, urinary, gastrointestinal, neurological systems and skin. Mercury level can be measured in plasma, urine, feces and hair samples. Urin...

  8. Preclinical safety evaluation of inhaled cyclosporine in propylene glycol.

    Science.gov (United States)

    Wang, Tao; Noonberg, Sarah; Steigerwalt, Ronald; Lynch, Maryellen; Kovelesky, Rosemary A; Rodríguez, Carlos A; Sprugel, Katherine; Turner, Nancy

    2007-01-01

    Cyclosporine inhalation solution has the potential to improve outcomes following lung transplantation by delivering high concentrations of an immunosuppressant directly to the allograft while minimizing systemic drug exposure and associated toxicity. The objective of these studies was to evaluate the potential toxicity of aerosolized cyclosporine formulated in propylene glycol when given by inhalation route to rats and dogs for 28 days. Sprague-Dawley rats received total inhaled doses of 0 (air), 0 (vehicle, propylene glycol), 7.4, 24.3, and 53.9 mg cyclosporine/kg/day. In a separate study, beagle dogs were exposed to 0, 4.4, 7.7, and 9.7 mg cyclosporine/kg/day. Endpoints used to evaluate potential toxicity of inhaled cyclosporine were clinical observations, body weight, food consumption, respiratory functions, toxicokinetics, and clinical/anatomic pathology. Daily administration of aerosolized cyclosporine did not result in observable accumulation of cyclosporine in blood or lung tissue. Toxicokinetic analysis from the rat study showed that the exposure of cyclosporine was approximately 18 times higher in the lung tissue compared to the blood. Systemic effects were consistent with those known for cyclosporine. There was no unexpected systemic toxicity or clinically limiting local respiratory toxicity associated with inhalation exposure to cyclosporine inhalation solution at exposures up to 2.7 times the maximum human exposure in either rats or dogs. There were no respiratory or systemic effects of high doses of propylene glycol relative to air controls. These preclinical studies demonstrate the safety of aerosolized cyclosporine in propylene glycol and support its continued clinical investigation in patients undergoing allogeneic lung transplantation.

  9. Inhalation cancer risk assessment of cobalt metal.

    Science.gov (United States)

    Suh, Mina; Thompson, Chad M; Brorby, Gregory P; Mittal, Liz; Proctor, Deborah M

    2016-08-01

    Cobalt compounds (metal, salts, hard metals, oxides, and alloys) are used widely in various industrial, medical and military applications. Chronic inhalation exposure to cobalt metal and cobalt sulfate has caused lung cancer in rats and mice, as well as systemic tumors in rats. Cobalt compounds are listed as probable or possible human carcinogens by some agencies, and there is a need for quantitative cancer toxicity criteria. The U.S. Environmental Protection Agency has derived a provisional inhalation unit risk (IUR) of 0.009 per μg/m(3) based on a chronic inhalation study of soluble cobalt sulfate heptahydrate; however, a recent 2-year cancer bioassay affords the opportunity to derive IURs specifically for cobalt metal. The mechanistic data support that the carcinogenic mode of action (MOA) is likely to involve oxidative stress, and thus, non-linear/threshold mechanisms. However, the lack of a detailed MOA and use of high, toxic exposure concentrations in the bioassay (≥1.25 mg/m(3)) preclude derivation of a reference concentration (RfC) protective of cancer. Several analyses resulted in an IUR of 0.003 per μg/m(3) for cobalt metal, which is ∼3-fold less potent than the provisional IUR. Future research should focus on establishing the exposure-response for key precursor events to improve cobalt metal risk assessment.

  10. Neurodevelopment of Infants in a Mercury Contaminated Crea in Zimbabwe

    OpenAIRE

    Bose-O’Reilly S.; Lettmeier B.; Shoko D.; Baeuml J.; Baskova-Schilling V.; Roider G.; Drasch G.; Siebert U.

    2013-01-01

    In Kadoma in Zimbabwe small-scale gold mining is widespread. Mothers and their infants are exposed in the mining communities to the toxic inorganic mercury vapors from processing the ore using elemental mercury. Methyl-mercury is a well known neurotoxin and endangers the regular development of children. This study examined the influence of exposure to elemental mercury for breast fed infants in Kadoma. 121 mother-child pairs were selected, 40 from a non-exposed control area, 81 from the expos...

  11. What are the toxicological effects of mercury in Arctic biota?

    DEFF Research Database (Denmark)

    Dietz, Rune; Sonne, Christian; Basu, Niladri

    2012-01-01

    This review critically evaluates the available mercury (Hg) data in Arctic marine biota and the Inuit population against toxicity threshold values. In particular marine top predators exhibit concentrations of mercury in their tissues and organs that are believed to exceed thresholds for biological...... to be one of the most vulnerable groups, with high concentrations of mercury recorded in brain tissue with associated signs of neurochemical effects. Evidence of increasing concentrations in mercury in some biota in Arctic Canada and Greenland is therefore a concern with respect to ecosystem health....

  12. Mercury contamination extraction

    Science.gov (United States)

    Fuhrmann, Mark; Heiser, John; Kalb, Paul

    2009-09-15

    Mercury is removed from contaminated waste by firstly applying a sulfur reagent to the waste. Mercury in the waste is then permitted to migrate to the reagent and is stabilized in a mercury sulfide compound. The stable compound may then be removed from the waste which itself remains in situ following mercury removal therefrom.

  13. Mercury poisoning dentistry: high-level indoor air mercury contamination at selected dental sites.

    Science.gov (United States)

    Khwaja, Mahmood A; Abbasi, Maryam Shabbir

    2014-01-01

    Mercury (Hg), also known as quick silver, is an essential constituent of dental amalgam. It is a toxic substance of global concern. Children are more at risk from mercury poisoning which affects their neurological development and brain. In the past, a number of studies at dental sites in many countries have been carried out and reported. The present report briefly describes and discusses our recent investigations carried out at 34 dental sites (teaching institutions, hospitals and private clinics) in Pakistan. It is evident from the data that at many sites the indoor mercury vapor levels exceed far above the permissible limit recommended for safe physical and mental health. At these sites, public in general and the medical, paramedical staff and vulnerable population in particular, are at most serious risk to health resulting from exposure to toxic and hazardous mercury. To minimize such risk, some of the recommendations are, best in-house environmental practices for occupational health and safety, mercury contaminated waste reduction at source, mercury specific legislation and ratification of Minamata convention on mercury by Pakistan and other world governments at the earliest time possible.

  14. Inhaled dust and disease

    Energy Technology Data Exchange (ETDEWEB)

    Holt, P.F.

    1987-01-01

    This book discusses the following: the respiratory system; respirable dust; the fate of inhaled dust; translocation and some general effects of inhaled dust; silicosis; experimental research on silica-related disease; natural fibrous silicates; asbestos dust levels and dust sources; asbestos-related diseases - asbestosis, lung cancer, mesothelioma and other diseases, cancers at sites other than lung and pleura; experimental research relating to asbestos-related diseases; asbestos hazard - mineral types and hazardous occupations, neighbourhood and domestic hazard; silicates other than asbestos-man-made mineral fibres, mineral silicates and cement; metals; coal mine dust, industrial carbon and arsenic; natural and synthetic organic substances; dusts that provoke allergic alveolitis; tobacco smoke.

  15. Interspecies modeling of inhaled particle deposition patterns

    Energy Technology Data Exchange (ETDEWEB)

    Martonen, T.B.; Zhang, Z.; Yang, Y.

    1992-01-01

    To evaluate the potential toxic effects of ambient contaminants or therapeutic effects of airborne drugs, inhalation exposure experiments can be performed with surrogate laboratory animals. Herein, an interspecies particle deposition theory is presented for physiologically based pharmacokinetic modeling. It is derived to improve animal testing protocols. The computer code describes the behavior and fate of particles in the lungs of human subjects and a selected surrogate, the laboratory rat. In the simulations CO2 is integrated with exposure chamber atmospheres, and its concentrations regulated to produce rat breathing profiles corresponding to selected levels of human physical activity. The dosimetric model is used to calculate total, compartmental (i.e., tracheobronchial and pulmonary), and localized distribution patterns of inhaled particles in rats and humans for comparable ventilatory conditions. It is demonstrated that the model can be used to predetermine the exposure conditions necessary to produce deposition patterns in rats that are equivalent to those in humans at prescribed physical activities.

  16. Aerobic Mercury-resistant bacteria alter Mercury speciation and retention in the Tagus Estuary (Portugal).

    Science.gov (United States)

    Figueiredo, Neusa L; Canário, João; O'Driscoll, Nelson J; Duarte, Aida; Carvalho, Cristina

    2016-02-01

    Aerobic mercury-resistant bacteria were isolated from the sediments of two highly mercury-polluted areas of the Tagus Estuary (Barreiro and Cala do Norte) and one natural reserve area (Alcochete) in order to test their capacity to transform mercury. Bacterial species were identified using 16S rRNA amplification and sequencing techniques and the results indicate the prevalence of Bacillus sp. Resistance patterns to mercurial compounds were established by the determination of minimal inhibitory concentrations. Representative Hg-resistant bacteria were further tested for transformation pathways (reduction, volatilization and methylation) in cultures containing mercury chloride. Bacterial Hg-methylation was carried out by Vibrio fluvialis, Bacillus megaterium and Serratia marcescens that transformed 2-8% of total mercury into methylmercury in 48h. In addition, most of the HgR bacterial isolates showed Hg(2+)-reduction andHg(0)-volatilization resulting 6-50% mercury loss from the culture media. In summary, the results obtained under controlled laboratory conditions indicate that aerobic Hg-resistant bacteria from the Tagus Estuary significantly affect both the methylation and reduction of mercury and may have a dual face by providing a pathway for pollution dispersion while forming methylmercury, which is highly toxic for living organisms. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Speciation of arsenic and mercury in feed: why and how?

    Directory of Open Access Journals (Sweden)

    Hedegaard, RV.

    2011-01-01

    Full Text Available The understanding of the mechanisms of biological activities and biotransformation of trace elements such as arsenic and mercury has improved during recent years with the help of chemical speciation studies. However, the most important practical application of elemental speciation is in the area of toxicology. Toxicological knowledge on the individual trace element species can lead to more specific legislation of hazardous substances found in feed. Examples here are arsenic, where the inorganic forms are the most toxic, and mercury, where the organic form methylmercury is more toxic than inorganic mercury. In the present paper an overview of the current knowledge on arsenic and mercury speciation in feed and analytical methodologies for arsenic and mercury speciation analysis are given. Additionally the current status and expected future developments within legislation for trace element speciation in feed as well as initiatives for the establishment of standardized methods for determination of inorganic arsenic and methylmercury are presented.

  18. Speciation of arsenic and mercury in feed: why and how?

    DEFF Research Database (Denmark)

    Hedegaard, Rikke Susanne Vingborg; Sloth, Jens Jørgen

    2011-01-01

    The understanding of the mechanisms of biological activities and biotransformation of trace elements such as arsenic and mercury has improved during recent years with the help of chemical speciation studies. However, the most important practical application of elemental speciation is in the area...... of toxicology. Toxicological knowledge on the individual trace element species can lead to more specific legislation of hazardous substances found in feed. Examples here are arsenic, where the inorganic forms are the most toxic, and mercury, where the organic form methylmercury is more toxic than inorganic...... mercury. In the present paper an overview of the current knowledge on arsenic and mercury speciation in feed and analytical methodologies for arsenic and mercury speciation analysis are given. Additionally the current status and expected future developments within legislation for trace element speciation...

  19. Mercury Quick Facts: Health Effects of Mercury Exposure

    Science.gov (United States)

    Mercury Quick Facts Health Effects of Mercury Exposure What is Elemental Mercury? Elemental (metallic) mercury is the shiny, silver-gray metal found in thermometers, barometers, and thermostats and other ...

  20. Pulmonary Toxicity of Cholinesterase Inhibitors

    Science.gov (United States)

    2006-01-01

    discusses respiratory and pulmonary toxicity through direct venomous and was synthesized at Porton Down, England, inhalation of AChEIs and indirect...effects on all aspects of res- in 1952. piration through systemic toxicity. Due to their high toxicity in mammals and volatile OP nerve agents can be... produc - century with the development of the present-day vesicants tion facility late in the war and moved it back to Russia, and AChEIs (or OP class

  1. [Inhaled corticosteroids for COPD

    NARCIS (Netherlands)

    Dekhuijzen, P.N.R.

    2003-01-01

    Over 60% of patients with COPD are treated with inhaled corticosteroids (ICS), even though their use is still subject to debate. The inflammatory process in the lungs of patients with COPD is dominated by macrophages, CD8+ T-lymphocytes, neutrophilic granulocytes and mast cells, as well as an increa

  2. Inhalants. Specialized Information Service.

    Science.gov (United States)

    Do It Now Foundation, Phoenix, AZ.

    The document presents a collection of articles about inhalant abuse. Article 1 presents findings on the psychophysiological effects related to the use of amyl or butyl nitrate as a "recreational drug." Article 2 suggests a strong association between chronic sniffing of the solvent toulene and irreversible brain damage. Article 3 warns…

  3. Inhalational Lung Disease

    Directory of Open Access Journals (Sweden)

    S Kowsarian

    2010-01-01

    Full Text Available Inhalational lung diseases are among the most important occupational diseases. Pneumoconiosis refers to a group of lung diseases result from inhalation of usually inorganic dusts such as silicon dioxide, asbestos, coal, etc., and their deposition in the lungs. The resultant pulmonary disorders depend on the susceptibility of lungs; size, concentration, solubility and fibrogenic properties of the inhaled particles; and duration of exposure. Radiographic manifestations of pneumoconiosis become apparent several years after exposure to the particles. However, for certain types of dusts, e.g., silicone dioxide crystal and beryllium, heavy exposure within a short period can cause an acute disease. Pulmonary involvement in asbestosis is usually in the lower lobes. On the contrary, in silicosis and coal worker pneumoconiosis, the upper lobes are involved predominantly. For imaging evaluation of pneumoconiosis, high-resolution computed tomography (CT is superior to conventional chest x-ray. Magnetic resonance imaging (MRI and positron emission tomography (PET scan are helpful in those with suspected tumoral lesions. In this essay, we reviewed the imaging aspects of inhalational lung disease.

  4. Mercury Intoxication in Rats: Iron and Vitamin B6 as A Potential Therapy

    Directory of Open Access Journals (Sweden)

    Mohammad Taimur Islam*

    2017-06-01

    Full Text Available Background: Mercury in any form is poisonous and mercury toxicity most commonly affects the nervous, gastrointestinal (GI and urinary systems. The aim of this study was to investigate the specific effect associated with mercury toxicity and to evaluate the effectiveness of iron and vitamin B6 supplement on mercury-induced toxicities in rats. Methods: This experiment was performed on 25 rats. All rats were randomly divided into five equal groups (5×5. Toxic signs and body weight change, hematological parameters like total erythrocyte count (TEC, total leukocyte count (TLC, hemoglobin content (Hb% and packed cell volume (PCV and postmortem changes in rats were investigated. Results: Rats treated with mercury intoxication showed severe toxic signs and significantly (P<0.01 reduced TEC, TLC, Hb content and PCV. However, rats treated with mercury intoxication in combination with iron and vitamin B6 showed physiological levels of hematological parameters. Mercury intoxication induced the congestion and necrosis in lung, liver, heart and kidney, whereas combined use of mercury intoxication, iron and vitamin B6 recovered the condition. Conclusion: Combined use of iron and vitamin B6 is highly protective against mercury toxicity.

  5. Mercury and toxic metals in ash from combustion and incineration processes; Mercurio y metales toxicos en cenizas provenientes de procesos de combustion e incineracion

    Energy Technology Data Exchange (ETDEWEB)

    Mugica, V.; Amador, M.A.; Torres, M.; Figueroa, J. de J. [Universidad Autonomo-Metropolitana-Azcapotzalco, Reynosa (Mexico)

    2003-07-01

    In Mexico, most of the ashes from combustion and incineration process were not appropriately disposed, they are either left on industrial yards and cliffs or thrown away in open spaces and then carried by the wind to places where they can harm population, affect aquatic environment or soils. For prevention and control, the knowledge on the concentration of trace elements in waste ashes is necessary. In this study, several oxidation methods for digestion of ashes followed by inductively coupled plasma emission spectrometry were evaluated. Hg, Cd, Cr, Cu, Ni, Pb and V were determined in ashes from coal and fuel oil combustion, as well as in ashes from the incineration of municipal, water treatment sludge, and medical wastes. Results showed important concentrations of different trace elements in the ashes. This suggests that adequate disposal of these wastes should be mandatory. On the other hand, concentration of trace elements in the leachates indicated that these wastes are not toxic and they could be disposed in sanitary landfill. 23 refs.

  6. Wildlife ecological screening levels for inhalation of volatile organic chemicals.

    Science.gov (United States)

    Gallegos, Patricia; Lutz, Jill; Markwiese, James; Ryti, Randall; Mirenda, Rich

    2007-06-01

    For most chemicals, evaluation of ecological risk typically does not address inhalation because ingestion dominates exposure. However, burrowing ecological receptors have an increased exposure potential from inhalation at sites contaminated with volatile chemicals in the subsurface. Evaluation of ecological risk from contaminants like volatile organic chemicals (VOCs) is constrained by a lack of relevant ecological screening levels (ESLs). To address this need, inhalation ESLs were developed for 16 VOCs: Acetone, benzene, carbon tetrachloride, chloroform, chloromethane, dichlorodifluoromethane, 1,1-dichloroethane, 1,2-dichloroethane, 1,1-dichloroethene, methylene chloride, tetrachloroethene, toluene, 1,1,1-trichloroethane, trichloroethene, trichlorofluoromethane, and total xylene. These ESLs are based on Botta's pocket gopher (Thomomys bottae) as a representative fossorial receptor. The ESLs are presented with an emphasis on the process for developing inhalation toxicity reference values to illustrate the selection of suitable toxicity data and effect levels from the literature. The resulting ESLs provide a quantitative method for evaluating ecological risk of VOCs through comparison to relevant exposure data such as direct burrow-air measurements. The toxicity reference value development and ESL calculation processes and assumptions detailed here are provided as bases from which risk assessors can use or refine to suit site-specific needs with respect to toxicity and exposure inputs.

  7. Mercury (Environmental Health Student Portal)

    Science.gov (United States)

    ... to dispose of (get rid of) mercury and mercury compounds properly, or they can wind up contaminating (polluting) soil, water, and air. Show more What products might have mercury in them? People have used mercury throughout history — ...

  8. Mercury emission, control and measurement from coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Wei-Ping [North China Electric Power Univ., Beijing (China). School of Energy and Power Engineering; Western Kentucky Univ., Bowling Green, KY (United States). Inst. for Combustion Science and Environmental Technology; Cao, Yan [Western Kentucky Univ., Bowling Green, KY (United States). Inst. for Combustion Science and Environmental Technology; Zhang, Kai [North China Electric Power Univ., Beijing (China). School of Energy and Power Engineering

    2013-07-01

    Coal-fired electric power generation accounts for 65% of U.S. emissions of sulfur dioxide (SO2), 22% of nitrogen oxides (NOx), and 37% of mercury (Hg). The proposed Clear Air Interstate Rule (CAIR) and Clean Air Mercury Rule (CAMR) will attempt to regulate these emissions using a cap-and-trade program to replace a number of existing regulatory requirements that will impact this industry over the next decade. Mercury emissions remain the largest source that has not yet been efficiently controlled, in part because this is one of the most expensive to control. Mercury is a toxic, persistent pollutant that accumulates in the food chain. During the coal combustion process, when both sampling and accurate measurements are challenging, we know that mercury is present in three species: elemental, oxidized and particulate. There are three basic types of mercury measurement methods: Ontario Hydro Method, mercury continuous emission monitoring systems (CEMS) and sorbent-based monitoring. Particulate mercury is best captured by electrostatic precipitators (ESP). Oxidized mercury is best captured in wet scrubbers. Elemental mercury is the most difficult to capture, but selective catalytic reduction units (SCRs) are able to convert elemental mercury to oxidized mercury allowing it to be captured by wet flue gas desulfurization (FGD). This works well for eastern coals with high chlorine contents, but this does not work well on the Wyoming Powder River Basin (PRB) coals. However, no good explanation for its mechanism, correlations of chlorine content in coal with SCR performance, and impacts of higher chlorine content in coal on FGD re-emission are available. The combination of SCR and FGD affords more than an 80% reduction in mercury emissions in the case of high chlorine content coals. The mercury emission results from different coal ranks, boilers, and the air pollution control device (APCD) in power plant will be discussed. Based on this UAEPA new regulation, most power plants

  9. Elemental mercury poisoning in occupational and residential settings.

    Science.gov (United States)

    Risher, John F; Nickle, Richard A; Amler, Sherlita N

    2003-08-01

    In its elemental form, mercury is the only metal that is in a liquid state at room temperature. It readily volatilizes at standard temperature and pressure, and its presence in open containers can result in biologically significant air concentrations in unventilated or poorly ventilated spaces. In recent years, elemental mercury has proven to be a potential source of toxicosis through either unintentional exposure or exposure resulting from inappropriate handling of liquid mercury acquired from school science laboratories or abandoned industrial facilities or warehouses. The shiny, silvery appearance of mercury in its liquid form makes it particularly enticing to children, and its insolubility in water and tendency to form beads when disturbed add to its mystique. This paper presents two case studies in which excessive exposure to elemental mercury vapor has resulted in adverse health effects in the exposed individuals: one in the workplace and one in a residential setting. These case studies serve to emphasize that primary care physicians, public health officials, and science educators need to recognize the potential risk posed by inhalation exposure to mercury vapors, and health practitioners need to be able to recognize the health signs and symptoms of such exposure. Public health professionals and those in charge of public and private education facilities should also be keenly aware of the necessity of prompt mitigation of human exposure should a spill or other mercury exposure scenario occur.

  10. Global Trends in Mercury Management

    Science.gov (United States)

    Choi, Kyunghee

    2012-01-01

    The United Nations Environmental Program Governing Council has regulated mercury as a global pollutant since 2001 and has been preparing the mercury convention, which will have a strongly binding force through Global Mercury Assessment, Global Mercury Partnership Activities, and establishment of the Open-Ended Working Group on Mercury. The European Union maintains an inclusive strategy on risks and contamination of mercury, and has executed the Mercury Export Ban Act since December in 2010. The US Environmental Protection Agency established the Mercury Action Plan (1998) and the Mercury Roadmap (2006) and has proposed systematic mercury management methods to reduce the health risks posed by mercury exposure. Japan, which experienced Minamata disease, aims vigorously at perfection in mercury management in several ways. In Korea, the Ministry of Environment established the Comprehensive Plan and Countermeasures for Mercury Management to prepare for the mercury convention and to reduce risks of mercury to protect public health. PMID:23230466

  11. Mercury speciation during in situ thermal desorption in soil

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chang Min, E-mail: cmpark80@gmail.com; Katz, Lynn E.; Liljestrand, Howard M.

    2015-12-30

    Highlights: • Impact of soil conditions on distribution and phase transitions of Hg was identified. • Metallic Hg was slowly transformed to Hg{sup 0} gas until the temperature reached 358.15 K. • Phase change of HgCl{sub 2(s)} completely occurred without decomposition at 335.15 K. • HgS remained solid in dry soil sharply decreased in the narrow temperature range. • Hg gas can be easily captured with higher vapor pressures of soil compositions. - Abstract: Metallic mercury (Hg{sup 0}) and its compounds are highly mobile and toxic environmental pollutants at trace level. In situ thermal desorption (ISTD) is one of the soil remediation processes applying heat and vacuum simultaneously. Knowledge of thermodynamic mercury speciation is imperative to understand the fate and transport of mercury during thermal remediation and operate the treatment processes in a cost-effective manner. Hence, speciation model for inorganic mercury was developed over a range of environmental conditions to identify distribution of dissolved mercury species and potential transformations of mercury at near source environment. Simulation of phase transitions for metallic mercury, mercury(II) chloride and mercury sulfide with temperature increase showed that complete vaporization of metallic mercury and mercury(II) chloride were achieved below the boiling point of water. The effect of soil compositions on mercury removal was also evaluated to better understand thermal remediation process. Higher vapor pressures expected both from soil pore water and inorganic carbonate minerals in soil as well as creation of permeability were significant for complete vaporization and removal of mercury.

  12. Environmental and health aspects of lighting: Mercury

    Energy Technology Data Exchange (ETDEWEB)

    Clear, R.; Berman, S.

    1993-07-01

    Most discharge lamps, including fluorescent lamps, metal halide lamps, and high pressure sodium lamps, contain Mercury, a toxic chemical. Lighting professionals need to be able to respond to questions about the direct hazards of Mercury from accidentally breaking lamps, and the potential environmental hazards of lamp operation and disposal. We calculated the exposures that could occur from an accidental breakage of lamps. Acute poisoning appears almost impossible. Under some circumstances a sealed environment, such as a space station, could be contaminated enough to make it unhealthy for long-term occupation. Mercury becomes a potential environmental hazard after it becomes methylated. Mercury is methylated in aquatic environments, where it may accumulate in fish, eventually rendering them toxic to people and other animals. Lighting causes Mercury to enter the environment directly from lamp disposal, and indirectly from power plant emissions. The environmental tradeoffs between incandescent and discharge lamps depend upon the amounts released by these two sources, their local concentrations, and their probabilities of being methylated. Indirect environmental effects of lighting also include the release of other heavy metals (Cadmium, Lead and Arsenic), and other air pollutants and carbon dioxide that are emitted by fossil fuel power plants. For a given light output, the level of power plant emissions depends upon the efficacy of the light source, and is thus much larger for incandescent lamps than for fluorescent or discharge lamps. As disposal and control technologies change the relative direct and indirect emissions from discharge and incandescent lamps will change.

  13. Public health department response to mercury poisoning: the importance of biomarkers and risks and benefits analysis for chelation therapy.

    Science.gov (United States)

    McKay, Charles A

    2013-12-01

    Chelation therapy is often used to treat mercury poisoning. Public health personnel are often asked about mercury toxicity and its treatment. This paper provides a public health department response to use of a mercury-containing cosmetic in Minnesota, a perspective on two unpublished cases of chelation treatment for postulated mercury toxicity, and comments on the use of a nonsystemic treatment for removal of mercury following the Iraqi seed coat poisoning incident. Physicians should evaluate sources of exposure, biomarkers, and risks and benefits before recommending chelation therapy for their patients. Potential risks to chelation therapy and its little understood subtle or latent effects are areas of public health concern.

  14. Estimation of the acute inhalation hazards of chemicals based on route-to-route and local endpoint extrapolation: Experience from Bulk Maritime Transport

    NARCIS (Netherlands)

    Höfer, T.; James, D.; Syversen, T.; Bowmer, T.

    2011-01-01

    Data on acute lethal inhalation toxicity from animal studies are commonly required for assessing the hazards to human health of volatile, gaseous and dusty chemicals or their mixtures. The International Maritime Organisation (IMO) made the provision of acute inhalation toxicity data a mandatory

  15. Estimation of the acute inhalation hazards of chemicals based on route-to-route and local endpoint extrapolation: Experience from Bulk Maritime Transport

    NARCIS (Netherlands)

    Höfer, T.; James, D.; Syversen, T.; Bowmer, T.

    2011-01-01

    Data on acute lethal inhalation toxicity from animal studies are commonly required for assessing the hazards to human health of volatile, gaseous and dusty chemicals or their mixtures. The International Maritime Organisation (IMO) made the provision of acute inhalation toxicity data a mandatory requ

  16. Mercury in the National Parks: Current Status and Effects

    Science.gov (United States)

    Flanagan, C.; Blett, T. F.; Morris, K.

    2012-12-01

    Mercury is a globally distributed contaminant that can harm human and wildlife health, and threaten resources the National Park Service (NPS) is charged with protecting. Due in part to emissions and long-range transport from coal burning power plants, even remote national park environments receive mercury deposition from the atmosphere. Given the concern regarding mercury, there are and have been many mercury monitoring initiatives in national parks to determine the risk from mercury contamination. This includes the study of litter fall at Acadia National Park (Maine), snow at Mount Rainier National Park (Washington), heron eggs at Indiana Dunes National Lakeshore (Indiana), bat hair at Mammoth Cave National Park (Kentucky), and panthers at Everglades National Park (Florida). Wet deposition is also measured at 16 national parks as part of the National Atmospheric Deposition Network / Mercury Deposition Network. Results from these studies indicate that mercury deposition is increasing or is elevated in many national parks, and fish and other biota have been found to contain levels of mercury above toxicity thresholds for impacts to both humans and wildlife. Current research coordinated by the NPS Air Resources Division (ARD) in Denver, Colorado, on the effects of mercury includes broad-scale assessments of mercury in fish, dragonfly larvae, and songbirds across 30+ national parks. Fish provide the trophic link to human and wildlife health, dragonfly larvae can describe fine-scale differences in mercury levels, and songbirds shed light on the risk to terrestrial ecosystems. External project partners include the U.S. Geological Survey, University of Maine, and the Biodiversity Research Institute. In addition, the dragonfly project engages citizen scientists in the collection of dragonfly larvae, supporting the NPS Centennial Initiative by connecting people to parks and advancing the educational mission, and increasing public awareness about mercury impacts. Much of

  17. Mercury speciation modeling using site specific chemical and redox data from the TNXOD OU

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, D.I.

    2000-03-22

    The objective of this study was to evaluate mercury speciation under reducing conditions expected in sediments at the TNX Outfall Delta Operable Unit. These changes in speciation would then be used to infer whether mercury toxicity and mobility would be expected to be significantly altered under reducing conditions. The results from this work suggest that mercury would likely become more strongly retained by the solid phase under reducing conditions than under oxidizing conditions at the TNX Outfall Delta Site. Considering that experimental results indicate that mercury is extremely tightly bound to the solid phase under oxidizing conditions, little mercury mobility would therefore be expected under reducing conditions.

  18. Who Can Use an Inhaler?

    Science.gov (United States)

    ... in a bit harder. Any kid, even a baby, can use a metered dose inhaler with a spacer and a mask. Once a kid is 5 or 6 years old, he or she can learn to use a metered dose inhaler with just a spacer. Most kids that age are also able to use a dry powder inhaler. Your doctor will help you decide what ...

  19. Mercury chloride-induced oxidative stress in human erythrocytes ...

    African Journals Online (AJOL)

    ONOS

    2010-01-25

    Jan 25, 2010 ... Mercury a highly toxic metal, results in a variety of adverse health effects ... the tissues of both animals and men (Lund et al.,1993;. Mahboob et al. ... mined the effects of VC and VE on pesticide and heavy metals toxicity in ...

  20. Conductometric Sensors for Detection of Elemental Mercury Vapor

    Science.gov (United States)

    Ryan, M. A.; Homer, M. L.; Shevade, A. V.; Lara, L. M.; Yen, S.-P. S.; Kisor, A. K.; Manatt, K. S.

    2008-01-01

    Several organic and inorganic materials have been tested for possible incorporation into a sensing array in order to add elemental mercury vapor to the suite of chemical species detected. Materials have included gold films, treated gold films, polymer-carbon composite films, gold-polymer-carbon composite films and palladium chloride sintered films. The toxicity of mercury and its adverse effect on human and animal health has made environmental monitoring of mercury in gas and liquid phases important (1,2). As consumer products which contain elemental mercury, such as fluorescent lighting, become more widespread, the need to monitor environments for the presence of vapor phase elemental mercury will increase. Sensors in use today to detect mercury in gaseous streams are generally based on amalgam formation with gold or other metals, including noble metals and aluminum. Recently, NASA has recognized a need to detect elemental mercury vapor in the breathing atmosphere of the crew cabin in spacecraft and has requested that such a capability be incorporated into the JPL Electronic Nose (3). The detection concentration target for this application is 10 parts-per-billion (ppb), or 0.08 mg/m3. In order to respond to the request to incorporate mercury sensing into the JPL Electronic Nose (ENose) platform, it was necessary to consider only conductometric methods of sensing, as any other transduction method would have required redesign of the platform. Any mercury detection technique which could not be incorporated into the existing platform, such as an electrochemical technique, could not be considered.

  1. Mercury accumulation in bats near hydroelectric reservoirs in Peninsular Malaysia.

    Science.gov (United States)

    Syaripuddin, Khairunnisa; Kumar, Anjali; Sing, Kong-Wah; Halim, Muhammad-Rasul Abdullah; Nursyereen, Muhammad-Nasir; Wilson, John-James

    2014-09-01

    In large man-made reservoirs such as those resulting from hydroelectric dam construction, bacteria transform the relatively harmless inorganic mercury naturally present in soil and the submerged plant matter into toxic methylmercury. Methylmercury then enters food webs and can accumulate in organisms at higher trophic levels. Bats feeding on insects emerging from aquatic systems can show accumulation of mercury consumed through their insect prey. In this study, we investigated whether the concentration of mercury in the fur of insectivorous bat species was significantly higher than that in the fur of frugivorous bat species, sampled near hydroelectric reservoirs in Peninsular Malaysia. Bats were sampled at Temenggor Lake and Kenyir Lake and fur samples from the most abundant genera of the two feeding guilds-insectivorous (Hipposideros and Rhinolophus) and frugivorous (Cynopterus and Megaerops) were collected for mercury analysis. We found significantly higher concentrations of total mercury in the fur of insectivorous bats. Mercury concentrations also differed significantly between insectivorous bats sampled at the two sites, with bats from Kenyir Lake, the younger reservoir, showing higher mercury concentrations, and between the insectivorous genera, with Hipposideros bats showing higher mercury concentrations. Ten bats (H. cf. larvatus) sampled at Kenyir Lake had mercury concentrations approaching or exceeding 10 mg/kg, which is the threshold at which detrimental effects occur in humans, bats and mice.

  2. Effects of mercury (II) species on cell suspension cultures of catharanthus roseus

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, L. (Hangzhou Univ. (China)); Cullen, W.R. (Univ. of British Columbia, Vancouver, British Columbia (Canada))

    1994-11-01

    Mercury has received considerable attention because of its high toxicity. Widespread contamination with mercury poses severe environmental problems despite our extensive knowledge of its toxicity in living systems. It is generally accepted that the toxicity of mercury is related to its oxidation states and species, the organic forms being more toxic than the inorganic forms. In the aquatic environment, the toxicity of mercury depends on the aqueous speciation of the mercuric ion (Hg[sup 2+]). Because of the complex coordination chemistry of mercury in aqueous systems, the nature of the Hg[sup 2+] species present in aquatic environments is influenced greatly by water chemistry (e. g, pH, inorganic ion composition, and dissolved organics). Consequently, the influence of environmental factors on the aqueous speciation of mercury has been the focus of much attention. However, there is very little information available regarding the effects of the species and speciation on Hg (II) toxicity in plant-tissue cultures. Catharanthus roseus (C. roseus), commonly called the Madagascar Periwinkle, is a member of the alkaloid rich family Apocynaceae. The present investigation was concerned with the toxicity of mercury on the growth of C. roseus cell suspension cultures as influenced by mercury (II) species and speciation. The specific objectives of the study were to (a) study the effects of mercury species on the growth of C. roseus cultures from the point of view of environmental biology and toxicology; (b) evaluate the effects of selenate, selenite and selected ligands such as chloride, 1-cysteine in the media on the acute toxicity of mercuric oxide; (c) determine the impact of the initial pH of the culture media on the toxicities of mercuric compounds; (d) discuss the dependence of the toxicity on the chemical species and speciation of Hg (II). 11 refs., 7 figs., 2 tabs.

  3. Characterisation and modelling of mercury speciation in urban air affected by gold mining - assessment of bioavailability

    Directory of Open Access Journals (Sweden)

    Cukrowska E. M.

    2013-04-01

    Full Text Available The growing global concern over the release of mercury to the environment has prompted specific inventories that quantify mercury emissions from various sources. Investigations of atmospheric mercury have been mostly done on gaseous species. Although, to assess human expose to mercury, especially in urban areas, the inhalable dust should be included in a study. The Witwatersrand Basin in South Africa is one of the most important gold mining regions in the world. Mercury (Hg, which occurs in gold-bearing ores, was also used for gold recoveries in previous centuries (19th and early 20th century and presently in illegal artisanal mining. The consequences of these mining activities were the release of Hg to the environment, mainly due to AMD from tailings dumps which are presently reprocessed. The city of Johannesburg is a multimillion population exposed strongly to industrial pollution. The aim of this study was to determine the magnitude of mercury pollution in this urban area and assess its bioavailability. The gaseous samples were collected by trapping mercury on various gold traps. Dust samples were collected from a ground and on inhalation levels (1–2 m above a ground. They were later separated into different fractions by micro sieving. Bioavailability of mercury in inhalable dust (25 μm was tested by leaching collected samples with artificial lung fluid (ALF, pH 4.5, Gray’s solution (pH 7.4 and water. The leaching conditions were selected to mimic lungs environment (incubator at 30°C, time 24 hrs, rotation of samples 150 rpm. Total concentrations of mercury in dust fractions were also determined after microwave digestion. The results showed extremely high concentration levels of mercury in air and dust in industrial areas. Especially high levels were found around presently reprocessed old gold tailings dumps, up to 900 000 μgl–1. The levels dropped significantly in CBD area but still showing elevated concentrations up to 10 μgl−1

  4. Mercury and selenium levels, and selenium:mercury molar ratios of brain, muscle and other tissues in bluefish (Pomatomus saltatrix) from New Jersey, USA

    Science.gov (United States)

    Burger, Joanna; Jeitner, Christian; Donio, Mark; Pittfield, Taryn; Gochfeld, Michael

    2015-01-01

    A number of contaminants affect fish health, including mercury and selenium, and the selenium: mercury molar ratio. Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for consumption of saltwater fish. Yet the relative ameliorating effects of selenium on toxicity within fish have not been examined, nor has the molar ratio in different tissues, (i.e. brain). We examined mercury and selenium levels in brain, kidney, liver, red and white muscle, and skin and scales in bluefish (Pomatomus saltatrix) from New Jersey to determine whether there were toxic levels of either metal, and we computed the selenium: mercury molar ratios by tissues. Total mercury averaged 0.32 ± 0.02 ppm wet weight in edible muscle and 0.09 ± 0.01 ppm in brain. Selenium concentration averaged 0.37 ± 0.03 in muscle and 0.36 ± 0.03 ppm in brain. There were significant differences in levels of mercury, selenium, and selenium: mercury molar ratios, among tissues. Mercury and selenium levels were correlated in kidney and skin/scales. Mercury levels were highest in kidney, intermediate in muscle and liver, and lowest in brain and skin/scales; selenium levels were also highest in kidney, intermediate in liver, and were an order of magnitude lower in the white muscle and brain. Mercury levels in muscle, kidney and skin/scales were positively correlated with fish size (length). Selenium levels in muscle, kidney and liver were positively correlated with fish length, but in brain; selenium levels were negatively correlated with fish length. The selenium: mercury molar ratio was negatively correlated with fish length for white muscle, liver, kidney, and brain, particularly for fish over 50 cm in length, suggesting that older fish experience less protective advantages of selenium against mercury toxicity than smaller fish, and that consumers of bluefish similarly receive less advantage from eating larger fish. PMID:23202378

  5. 有关卤代类吸入麻醉药的肝、肾保护与肝、肾毒性作用的争论%The debate on liver and kidney protection or toxicity about halogenated inhalation anesthetics

    Institute of Scientific and Technical Information of China (English)

    袁亚伟; 俞卫锋

    2015-01-01

    经典的卤代类吸入麻醉药如氟烷等有肝、肾毒性的报告。但最近的研究证实,卤代类吸入麻醉药可对损害的脏器起到明显的保护作用。因此,对卤代类吸入麻醉药究竟是有肝、肾毒性还是保护作用存在着争论。新型卤代类吸入麻醉药因代谢率低,在体内产生的有损害作用的代谢产物的量很少,故引起肝、肾损害的几率几乎可以忽略。卤代类吸入麻醉药对不同脏器的保护机制各异,其中保肝、护肺作用主要通过抑制炎症反应实现,对心脏的保护作用则主要通过激活某些信号蛋白而产生。卤代类吸入麻醉药的脏器保护和损害作用是相对的,即保护是对已损害脏器的保护,而损害是对正常脏器的损害。此外,卤代类吸入麻醉药的脏器保护和损害作用均有一定的时效性,损害是暂时的、有自限性的,保护同样是短期的而不是永久的。%The classical halogenated inhalation anesthetics such as halothane may have liver and kidney toxicity based on some clinical reports. Recent studies have conifrmed that halogenated inhalation anesthetics can damage or protect organs, so there is a debate in halogenated inhalation anesthetics resulting in liver and kidney damage or protection. Probability for new halogenated inhalation anesthetics causing liver and kidney damage is almost negligible because its metabolic rate is low and the amount of the harmful metabolites produced in vivo is a little. The protection of halogenated inhalation anesthetics to different organs had different mechanisms, in which its protection to liver and lung is mainly realized by inhibiting the inflammatory reactions while its protection to heart is mainly achieved by activating certain signaling proteins. In brief, its protection and damage to organs are relative, the so-called protection is the protection to the damaged organs, and the so-called damage is the damage to the normal

  6. Below a Historic Mercury Mine: Non-linear Patterns of Mercury Bioaccumulation in Aquatic Organisms

    Science.gov (United States)

    Haas, J.; Ichikawa, G.; Ode, P.; Salsbery, D.; Abel, J.

    2001-12-01

    Unlike most heavy metals, mercury is capable of bioaccumulating in aquatic food-chains, primarily because it is methylated by bacteria in sediment to the more toxic methylmercury form. Mercury concentrations in a number of riparian systems in California are highly elevated as a result of historic mining activities. These activities included both the mining of cinnabar in the coastal ranges to recover elemental mercury and the use of elemental mercury in the gold fields of the Sierra Nevada Mountains. The most productive mercury mining area was the New Almaden District, now a county park, located in the Guadalupe River drainage of Santa Clara County, where cinnabar was mined and retorted for over 100 years. As a consequence, riparian systems in several subwatersheds of the Guadalupe River drainage are contaminated with total mercury concentrations that exceed state hazardous waste criteria. Mercury concentrations in fish tissue frequently exceed human health guidelines. However, the potential ecological effects of these elevated mercury concentrations have not been thoroughly evaluated. One difficulty is in extrapolating sediment concentrations to fish tissue concentrations without accounting for physical and biological processes that determine bioaccumulation patterns. Many processes, such as methylation and demethylation of mercury by bacteria, assimilation efficiency in invertebrates, and metabolic rates in fish, are nonlinear, a factor that often confounds attempts to evaluate the effects of mercury contamination on aquatic food webs. Sediment, benthic macroinvertebrate, and fish tissue samples were collected in 1998 from the Guadalupe River drainage in Santa Clara County at 13 sites upstream and downstream from the historic mining district. Sediment and macroinvertebrate samples were analyzed for total mercury and methylmercury. Fish samples were analyzed for total mercury as whole bodies, composited by species and size. While linear correlations of sediment

  7. Development of novel activated carbon-based adsorbents for the control of mercury emissions from coal-fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    Radisav D. Vidic

    1999-03-01

    In addition to naturally occurring mercury sources, anthropogenic activities increase the mercury loading to the environment. Although not all produced mercury is dissipated directly into the environment, only minor portions of the total production are stocked or recycled, and the rest of the mercury and its compounds is finally released in some way into atmosphere, surface waters and soil, or ends in landfills dumps, and refuse. Since mercury and its compounds are highly toxic, their presence in the environment constitutes potential impact on all living organisms, including man. The first serious consequence of industrial mercury discharges causing neurological disorder even death occurred in Minimata, Japan in 1953. Systematic studies showed that mercury poisoning is mainly found in fish-eating populations. However, various levels of mercury are also found in food other than fish. During the past several decades, research has been conducted on the evaluation of risks due to exposure to mercury and the development of control technologies for mercury emissions. In 1990, the Clean Air Act Amendments listed mercury, along with 10 other metallic species, as a hazardous air pollutant (HAP). This has further stimulated research for mercury control during the past several years. The impact of mercury on humans, sources of mercury in the environment, current mercury control strategies and the objective of this research are discussed in this section.

  8. Assessment of Mercury Bioaccumulation in Zebra Cichlid (Cichlasoma Nigrofasciatum Exposed to Sublethal Concentrations of Permethrin

    Directory of Open Access Journals (Sweden)

    Mahdi Banaee

    2014-12-01

    Full Text Available Background: Aquatic ecosystems are frequently subjected to contamination by toxic heavy metals and pesticides, yet very little is known about the influence of pesticides on bioaccumulation of heavy metals in aquatic organisms. Mercury is a toxic metal with no known biological benefit to organisms. Bioavailability of mercury in aquatic environments depends on biological and non-biological parameters including other pollutants. Therefore, the objectives of this research were to determine the effects of permethrin on bioaccumulation of mercury in zebra cichlid. Methods: Acute toxicity (LC50 of permethrin and mercury chloride was evaluated by estimating mortality in Probit Model in SPSS (version 19.0 IBM. In sub-lethal toxicity, zebra cichlid (Cichlasoma nigrofasciatum was exposed to various concentrations of permethrin (0.0, 0.40, 0.80, 1.20 and 1.60 µg.L-1 combined with 20 µg.L-1 mercury chloride for 15 days. At the end of the experiment, mercury concentrations were measured using ICP-OES-Perkin elmer (optima 7300-DV. Results: 96 h LC50 values of permethrin and mercury for C. nigrofasciatum were calculated to be 17.55 µg.L-1 and 140.38 µg.L-1, respectively. Our results clearly showed that the bioaccumulation of mercury in the specimens increased with increasing concentrations of permethrin to 1.20 and 1.60 µg.L-1. Conclusion: Increasing the concentration of permethrin had synergistic effects on the bioaccumulation of mercury in fish.

  9. [Chronic occupational metallic mercurialism].

    Science.gov (United States)

    Faria, Marcília de Araújo Medrado

    2003-02-01

    This is a review on current knowledge of chronic occupational mercurialism syndrome. Major scientific studies and reviews on clinical manifestation and physiopathology of mercury poisoning were evaluated. The search was complemented using Medline and Lilacs data. Erethism or neuropsychological syndrome, characterized by irritability, personality change, loss of self-confidence, depression, delirium, insomnia, apathy, loss of memory, headaches, general pain, and tremors, is seen after exposure to metallic mercury. Hypertension, renal disturbances, allergies and immunological conditions are also common. Mercury is found in many different work processes: industries, gold mining, and dentistry. As prevention measures are not often adopted there is an increasing risk of mercury poisoning. The disease has been under diagnosed even though 16 clinical forms of mercury poisoning are described by Brazilian regulations. Clinical diagnosis is important, especially because abnormalities in the central nervous, renal and immunological systems can be detected using current medical technology, helping to develop the knowledge and control measures for mercurialism.

  10. Geochemical, Genetic, and Community Controls on Mercury

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Judy D.

    2014-11-10

    The sulfate-reducing bacteria (SRB) are soil bacteria that share two common characteristics, strict anaerobiosis and the ability to respire sulfate. The metabolic activities of these bacteria play significant roles in the global sulfur cycle, anaerobic degradation of biomass, biological metal corrosion in the environment and, recently, degradation of toxic compounds. The accumulation of evidence suggests these bacteria are also key to the production of the neurotoxin methylmercury in environmental settings. We propose to use our experience with the development of genetics in sulfate-reducing bacteria of the genus Desulfovibrio to create mutations that will eliminate the methylation of mercury, thereby identifying the genes essential for this process. This information may allow the environmental monitoring of the mercury methylation potential to learn the location and quantity of the production this toxin. From these data, more accurate predictive models of mercury cycling can be generated.

  11. Iloprost inhalation in mild asthma.

    Science.gov (United States)

    Majeski, Elizabeth; Hoskins, Aimee; Dworski, Ryszard; Sheller, James R

    2012-11-01

    To determine the feasibility of administering iloprost by inhalation in patients with mild atopic asthma. Volunteers underwent supervised inhalation of iloprost in the clinic with measurement of spirometry and blood pressure for 2 hours. The volunteers then inhaled iloprost four times daily at a dose of 2.5 or 5 μg for 14 days. Spirometry, asthma questionnaires, peak flow diaries, measurement of methacholine responsiveness, and exhaled nitric oxide concentrations were obtained prior to and after the treatment period. Chronic inhalation of iloprost (2.5-5 μg) did not alter spirometry or methacholine responsiveness. Inhaled iloprost in carefully selected volunteers with mild asthma appears to be a suitable intervention to explore the effects of prostacyclin in human asthma.

  12. Effect of environmental exposure to mercury on the functioning of the human body

    Directory of Open Access Journals (Sweden)

    Maciej Cyran

    2013-09-01

    Full Text Available Mercury is classified as a heavy metal and thus is commonly referred to as a death metal due to its high toxicity. In the environment it occurs in metallic form or in combination with other compounds. Amidst the sources of exposure to mercury, the most important environmental sources are dental amalgam and mercury vapor from the production of chlorine which is the most important source of occupational exposure. Mercury is easily soluble in fats, so it penetrates through biological membranes. Both - acute and chronic mercury poisoning causes characteristic clinical symptoms. There are several connections between exposure to this metal and toxic effects on the nervous system, cardiovascular system, endocrine system and kidneys. Thus mercury damages the structure of many organs and impairs their function

  13. New science challenges old notion that mercury dental amalgam is safe.

    Science.gov (United States)

    Homme, Kristin G; Kern, Janet K; Haley, Boyd E; Geier, David A; King, Paul G; Sykes, Lisa K; Geier, Mark R

    2014-02-01

    Mercury dental amalgam has a long history of ostensibly safe use despite its continuous release of mercury vapor. Two key studies known as the Children's Amalgam Trials are widely cited as evidence of safety. However, four recent reanalyses of one of these trials now suggest harm, particularly to boys with common genetic variants. These and other studies suggest that susceptibility to mercury toxicity differs among individuals based on multiple genes, not all of which have been identified. These studies further suggest that the levels of exposure to mercury vapor from dental amalgams may be unsafe for certain subpopulations. Moreover, a simple comparison of typical exposures versus regulatory safety standards suggests that many people receive unsafe exposures. Chronic mercury toxicity is especially insidious because symptoms are variable and nonspecific, diagnostic tests are often misunderstood, and treatments are speculative at best. Throughout the world, efforts are underway to phase down or eliminate the use of mercury dental amalgam.

  14. Health risks following ingestion of mercury and zinc air batteries.

    Science.gov (United States)

    Nolan, M; Tucker, I

    1981-01-01

    This paper reports on a study set up to assess the corrosive behaviour of mercury and zinc air batteries in the gastric juice environment of the stomach. The results show a relatively rapid rate of corrosion for charged mercury batteries. In contrast, the zinc air battery showed no visible corrosion under the same conditions. In view of the toxic dangers from leakage of mercury batteries, it is recommended that steps be taken to ensure that such batteries do not remain in the acidic environment of the stomach, should ingestion occur.

  15. MERCURY ADSORPTION BY ARTHOBACTER GLOBIFORMIS AND SPIRULINA PLATENSIS

    Directory of Open Access Journals (Sweden)

    T. L. Kalabegishvili

    2011-06-01

    Full Text Available The increasing contamination of soil, sediment, and water with heavy metals by natural and industrial processes is a worldwide problem. Many bacteria and microalgae have demonstrated ability to absorb toxic elements. To study mercury biosorption by bacteria Arthrobacter globiformis and microalga Spirulina platensis neutron activation analysis (NAA was applied. The process of mercury biosorption by these media was described by Freundlich and Langmuir-Freundlich Model. Both microorganisms showed a great potential to be used as biosorbing agents for mercury removal from the environment.

  16. Mercury Calibration System

    Energy Technology Data Exchange (ETDEWEB)

    John Schabron; Eric Kalberer; Joseph Rovani; Mark Sanderson; Ryan Boysen; William Schuster

    2009-03-11

    U.S. Environmental Protection Agency (EPA) Performance Specification 12 in the Clean Air Mercury Rule (CAMR) states that a mercury CEM must be calibrated with National Institute for Standards and Technology (NIST)-traceable standards. In early 2009, a NIST traceable standard for elemental mercury CEM calibration still does not exist. Despite the vacature of CAMR by a Federal appeals court in early 2008, a NIST traceable standard is still needed for whatever regulation is implemented in the future. Thermo Fisher is a major vendor providing complete integrated mercury continuous emissions monitoring (CEM) systems to the industry. WRI is participating with EPA, EPRI, NIST, and Thermo Fisher towards the development of the criteria that will be used in the traceability protocols to be issued by EPA. An initial draft of an elemental mercury calibration traceability protocol was distributed for comment to the participating research groups and vendors on a limited basis in early May 2007. In August 2007, EPA issued an interim traceability protocol for elemental mercury calibrators. Various working drafts of the new interim traceability protocols were distributed in late 2008 and early 2009 to participants in the Mercury Standards Working Committee project. The protocols include sections on qualification and certification. The qualification section describes in general terms tests that must be conducted by the calibrator vendors to demonstrate that their calibration equipment meets the minimum requirements to be established by EPA for use in CAMR monitoring. Variables to be examined include linearity, ambient temperature, back pressure, ambient pressure, line voltage, and effects of shipping. None of the procedures were described in detail in the draft interim documents; however they describe what EPA would like to eventually develop. WRI is providing the data and results to EPA for use in developing revised experimental procedures and realistic acceptance criteria based on

  17. Toxicity of metal mixtures to chick embryos

    Energy Technology Data Exchange (ETDEWEB)

    Birge, W.J.; Roberts, O.W.; Black, J.A.

    1976-09-01

    The toxic effects of mercury/selenium and certain other metal mixtures on the chick embryo are examined to determine whether antagonistic, additive or synergistic interactions occur. White Plymouth Rock chicken eggs were treated by yolk injection with cadmium chloride, mercuric chloride, zinc chloride and sodium selenate. Test aliquots were injected prior to incubation using the needle track procedure. Using a sample size of 200, percent survival was determined as hatchability of experimental eggs/controls. Metal mixtures used included mercury/cadmium, mercury/selenium, mercury/zinc, cadmium/selenium, and cadmium/zinc. Except for mercury/selenium, all other metal mixtures gave actual values that were within 5% of those for additive toxic effects. Actual hatchability frequencies for test concentrations of mercury/selenium indicated a moderate degree of synergism. Results indicate that the strong mercury/selenium synergism which affects embryonic development in the carp does not apply for the chick embryo; that most two-way combinations of cadmium, mercury, selenium and zinc exert purely additive effects on chick hatchability; and that these metal mixtures give no discernible antagonistic interactions which affect survival of chick embryos. (MFB)

  18. Inhaled Antibiotics for Gram-Negative Respiratory Infections.

    Science.gov (United States)

    Wenzler, Eric; Fraidenburg, Dustin R; Scardina, Tonya; Danziger, Larry H

    2016-07-01

    Gram-negative organisms comprise a large portion of the pathogens responsible for lower respiratory tract infections, especially those that are nosocomially acquired, and the rate of antibiotic resistance among these organisms continues to rise. Systemically administered antibiotics used to treat these infections often have poor penetration into the lung parenchyma and narrow therapeutic windows between efficacy and toxicity. The use of inhaled antibiotics allows for maximization of target site concentrations and optimization of pharmacokinetic/pharmacodynamic indices while minimizing systemic exposure and toxicity. This review is a comprehensive discussion of formulation and drug delivery aspects, in vitro and microbiological considerations, pharmacokinetics, and clinical outcomes with inhaled antibiotics as they apply to disease states other than cystic fibrosis. In reviewing the literature surrounding the use of inhaled antibiotics, we also highlight the complexities related to this route of administration and the shortcomings in the available evidence. The lack of novel anti-Gram-negative antibiotics in the developmental pipeline will encourage the innovative use of our existing agents, and the inhaled route is one that deserves to be further studied and adopted in the clinical arena.

  19. Inhaled Antibiotics for Gram-Negative Respiratory Infections

    Science.gov (United States)

    Fraidenburg, Dustin R.; Scardina, Tonya

    2016-01-01

    SUMMARY Gram-negative organisms comprise a large portion of the pathogens responsible for lower respiratory tract infections, especially those that are nosocomially acquired, and the rate of antibiotic resistance among these organisms continues to rise. Systemically administered antibiotics used to treat these infections often have poor penetration into the lung parenchyma and narrow therapeutic windows between efficacy and toxicity. The use of inhaled antibiotics allows for maximization of target site concentrations and optimization of pharmacokinetic/pharmacodynamic indices while minimizing systemic exposure and toxicity. This review is a comprehensive discussion of formulation and drug delivery aspects, in vitro and microbiological considerations, pharmacokinetics, and clinical outcomes with inhaled antibiotics as they apply to disease states other than cystic fibrosis. In reviewing the literature surrounding the use of inhaled antibiotics, we also highlight the complexities related to this route of administration and the shortcomings in the available evidence. The lack of novel anti-Gram-negative antibiotics in the developmental pipeline will encourage the innovative use of our existing agents, and the inhaled route is one that deserves to be further studied and adopted in the clinical arena. PMID:27226088

  20. Exubera. Inhale therapeutic systems.

    Science.gov (United States)

    Bindra, Sanjit; Cefalu, William T

    2002-05-01

    Inhale, in colaboration with Pfizer and Aventis Pharma (formerly Hoechst Marion Roussel; HMR), is developing an insulin formulation utilizing its pulmonary delivery technology for macromolecules for the potential treatment of type I and II diabetes. By July 2001, the phase III program had been completed and the companies had begun to assemble data for MAA and NDA filings; however, it was already clear at this time that additional data might be required for filing. By December 2001, it had been decided that the NDA should include an increased level of controlled, long-term pulmonary safety data in diabetic patients and a major study was planned to be completed in 2002, with the NDA filed thereafter (during 2002). US-05997848 was issued to Inhale Therapeutic Systems in December 1999, and corresponds to WO-09524183, filed in February 1995. Equivalent applications have appeared to date in Australia, Brazil, Canada, China, Czech Republic, Europe, Finland, Hungary, Japan, Norway, New Zealand, Poland and South Africa. This family of applications is specific to pulmonary delivery of insulin. In February 1999, Lehman Brothers gave this inhaled insulin a 60% probability of reaching market, with a possible launch date of 2001. The analysts estimated peak sales at $3 billion in 2011. In May 2000, Aventis predicted that estimated peak sales would be in excess of $1 billion. In February 2000, Merrill Lynch expected product launch in 2002 and predicted that it would be a multibillion-dollar product. Analysts Merril Lynch predicted, in September and November 2000, that the product would be launched by 2002, with sales in that year of e75 million, rising to euro 500 million in 2004. In April 2001, Merrill Lynch predicted that filing for this drug would occur in 2001. Following the report of the potential delay in regulatory filing, issued in July 2001, Deutsche Banc Alex Brown predicted a filing would take place in the fourth quarter of 2002 and launch would take place in the first

  1. Mercury from chlor-alkali plants: measured concentrations in food product sugar

    Directory of Open Access Journals (Sweden)

    Hightower Jane

    2009-01-01

    Full Text Available Abstract Mercury cell chlor-alkali products are used to produce thousands of other products including food ingredients such as citric acid, sodium benzoate, and high fructose corn syrup. High fructose corn syrup is used in food products to enhance shelf life. A pilot study was conducted to determine if high fructose corn syrup contains mercury, a toxic metal historically used as an anti-microbial. High fructose corn syrup samples were collected from three different manufacturers and analyzed for total mercury. The samples were found to contain levels of mercury ranging from below a detection limit of 0.005 to 0.570 micrograms mercury per gram of high fructose corn syrup. Average daily consumption of high fructose corn syrup is about 50 grams per person in the United States. With respect to total mercury exposure, it may be necessary to account for this source of mercury in the diet of children and sensitive populations.

  2. Mercury exposure and malaria prevalence among gold miners in Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Silbergeld Ellen K.

    2002-01-01

    Full Text Available Economic development, including resource extraction, can cause toxic exposures that interact with endemic infectious diseases. Mercury is an immunotoxic metal used in the amalgamation of gold, resulting in both occupational exposures and environmental pollution. A cross-sectional medical survey was conducted in 1997 on 135 garimpeiros in Para, Brazil, because of their risks of both mercury exposure and malaria transmission. Mean levels of blood and urine mercury were well above non-exposed background levels. Twenty-six subjects had malaria parasitemia: Health symptoms consistent with mercury exposure were reported, but neither symptoms nor signs correlated with mercury levels in blood or urine. We did not find a dose response relationship between mercury exposure and likelihood of prevalent malaria infection, but there was a possible reduction in acquisition of immunity that may be associated with conditions in gold mining, including mercury exposure.

  3. Mercury in fish and adverse reproductive outcomes: results from South Carolina

    OpenAIRE

    Burch, James B.; Wagner Robb, Sara; Puett, Robin; Cai, Bo; Wilkerson, Rebecca; Karmaus, Wilfried; Vena, John; Svendsen, Erik

    2014-01-01

    Background Mercury is a metal with widespread distribution in aquatic ecosystems and significant neurodevelopmental toxicity in humans. Fish biomonitoring for total mercury has been conducted in South Carolina (SC) since 1976, and consumption advisories have been posted for many SC waterways. However, there is limited information on the potential reproductive impacts of mercury due to recreational or subsistence fish consumption. Methods To address this issue, geocoded residential locations f...

  4. Oral Lichenoid Contact Lesions to Mercury and Dental Amalgam—A Review

    OpenAIRE

    Helen McParland; Saman Warnakulasuriya

    2012-01-01

    Human oral mucosa is subjected to many noxious stimuli. One of these substances, in those who have restorations, is dental amalgam which contains mercury. This paper focuses on the local toxic effects of amalgam and mercury from dental restorations. Components of amalgam may, in rare instances, cause local side effects or allergic reactions referred to as oral lichenoid lesions (OLLs). OLLs to amalgams are recognised as hypersensitivity reactions to low-level mercury exposure. The use of patc...

  5. What Do We Know of Childhood Exposures to Metals (Arsenic, Cadmium, Lead, and Mercury) in Emerging Market Countries?

    OpenAIRE

    Lindsey M. Horton; Mortensen, Mary E.; Yulia Iossifova; Wald, Marlena M.; Paula Burgess

    2013-01-01

    Arsenic, cadmium, lead, and mercury present potential health risks to children who are exposed through inhalation or ingestion. Emerging Market countries experience rapid industrial development that may coincide with the increased release of these metals into the environment. A literature review was conducted for English language articles from the 21st century on pediatric exposures to arsenic, cadmium, lead, and mercury in the International Monetary Fund's (IMF) top 10 Emerging Market countr...

  6. JV Task 96 - Phase 2 - Investigating the Importance of the Mercury-Selenium Interaction

    Energy Technology Data Exchange (ETDEWEB)

    Nicholas Ralston; Laura Raymond

    2008-03-01

    In order to improve the understanding of the mercury issue, it is vital to study mercury's effects on selenium physiology. While mercury present in the environment or food sources may pose health risks, the protective effects of selenium have not been adequately considered in establishing regulatory policy. Numerous studies report that vulnerability to mercury toxicity is inversely proportional to selenium status or level. However, selenium status has not been considered in the development of the reference dosage levels for mercury exposure. Experimental animals fed low-selenium diets are far more vulnerable to mercury toxicity than animals fed normal selenium, and animals fed selenium-rich diets are even more resistant. Selenium-dependent enzymes in brain and endocrine tissues can be impaired by excessive mercury exposure, apparently because mercury has an extremely high binding affinity for selenium. When selenium becomes bound to mercury, it is unable to participate in the metabolic cycling of selenoprotein synthesis. Because of mercury-dependent impairments of selenoprotein synthesis, various antioxidant and regulatory functions in brain biochemistry are compromised. This report details a 2-year multiclient-funded research program designed to examine the interactions between mercury and selenium in animal models. The studies explored the effects of dietary intakes of toxic amounts of methylmercury and the protective effects of the normal dietary range of selenium in counteracting mercury toxicity. This study finds that the amounts of selenium present in ocean fish are sufficient to protect against far larger quantities of methylmercury than those present in typical seafoods. Toxic effects of methylmercury exposure were not directly proportional to mercury concentrations in blood, brain, or any other tissues. Instead, mercury toxicity was proportional to molar ratios of mercury relative to selenium. In order to accurately assess risk associated with

  7. Effects of mercury release from amalgam dental restorations during cremation on soil mercury levels of three New Zealand crematoria

    Energy Technology Data Exchange (ETDEWEB)

    Nieschmidt, A.K.; Kim, N.D. [Univ. of Waikato, Hamilton (New Zealand)

    1997-05-01

    A vast amount of research has been undertaken in the last 15-20 years on the corrosion reactions occurring in dental amalgam, release of mercury from amalgam restorations, and the toxic effects of this released mercury on the human body. However, one environmental aspect of amalgam dental restorations that has not received a great deal of attention is the release of mercury during cremation. Mercury is liberated during cremation both because dental amalgams are unstable at cremation temperatures (650-700{degrees}C) and because the free mercury metal is highly volatile. In New Zealand, 58% of deaths are followed by cremation and this figure is likely to rise in the future. This increasing use of cremation as the method of corpse disposal, coupled with the fact that each amalgam restoration is approximately 50% mercury, implies that a significant amount of mercury may be emitted into the environment every year. This study examines mercury released from crematoria in New Zealand. 20 refs., 2 figs., 5 tabs.

  8. Cherry-flavoured electronic cigarettes expose users to the inhalation irritant, benzaldehyde.

    Science.gov (United States)

    Kosmider, Leon; Sobczak, Andrzej; Prokopowicz, Adam; Kurek, Jolanta; Zaciera, Marzena; Knysak, Jakub; Smith, Danielle; Goniewicz, Maciej L

    2016-04-01

    Many non-cigarette tobacco products, including e-cigarettes, contain various flavourings, such as fruit flavours. Although many flavourings used in e-cigarettes are generally recognised as safe when used in food products, concerns have been raised about the potential inhalation toxicity of these chemicals. Benzaldehyde, which is a key ingredient in natural fruit flavours, has been shown to cause irritation of respiratory airways in animal and occupational exposure studies. Given the potential inhalation toxicity of this compound, we measured benzaldehyde in aerosol generated in a laboratory setting from flavoured e-cigarettes purchased online and detected benzaldehyde in 108 out of 145 products. The highest levels of benzaldehyde were detected in cherry-flavoured products. The benzaldehyde doses inhaled with 30 puffs from flavoured e-cigarettes were often higher than doses inhaled from a conventional cigarette. Levels in cherry-flavoured products were >1000 times lower than doses inhaled in the workplace. While e-cigarettes seem to be a promising harm reduction tool for smokers, findings indicate that using these products could result in repeated inhalation of benzaldehyde, with long-term users risking regular exposure to the substance. Given the uncertainty surrounding adverse health effects stemming from long-term inhalation of flavouring ingredients such as benzaldehyde, clinicians need to be aware of this emerging risk and ask their patients about use of flavoured e-cigarettes.

  9. Accumulation and fluxes of mercury in terrestrial and aquatic food chains with special reference to Finland

    Directory of Open Access Journals (Sweden)

    Martin Lodenius

    2013-03-01

    Full Text Available Mercury is known for its biomagnification especially in aquatic food chains and for its toxic effects on different organisms including man. In Finland mercury has formerly been used in industry and agriculture and in addition many anthropogenic activities may increase the mercury levels in ecosystems. Phenyl mercury was widely used as slimicide in the pulp and paper industry in the 1950s and 1960s. In the chlor-alkali industry metallic mercury was used as catalyst at three plants. The most toxic form of mercury, methyl mercury, may be formed in soils, water, sediments and organisms. Many factors, including microbial activity, temperature, oxygen status etc., affect the methylation rate. In the lake ecosystem bioaccumulation of methyl mercury is very strong. In early 1980s there was a restriction of fishing concerning approximately 4000 km2 of lakes and sea areas because of mercury pollution. In aquatic systems we still find elevated concentrations near former emission sources. Long-range atmospheric transport and mechanical operations like ditching and water regulation may cause increased levels of mercury in the aquatic ecosystems. In the Finnish agriculture organic mercury compounds were used for seed dressing until 1992. Although the amounts used were substantial the concentrations in agricultural soils have remained rather low. In terrestrial food chains bioaccumulation is normally weak with low or moderate concentration at all ecosystem levels. Due to a weak uptake through roots terrestrial, vascular plants normally contain only small amounts of mercury. There is a bidirectional exchange of mercury between vegetation and atmosphere. Contrary to vascular plants, there is a very wide range of concentrations in fungi. Mercury may pose a threat to human health especially when accumulated in aquatic food chains.

  10. Compromised immune competence in free-living tree swallows exposed to mercury.

    Science.gov (United States)

    Hawley, Dana M; Hallinger, Kelly K; Cristol, Daniel A

    2009-07-01

    Mercury is a pervasive environmental contaminant and a well-documented immunosuppressor. However, little is known about the effects of mercury contamination on health of free-living vertebrate populations. The South River in Virginia, USA was heavily contaminated with industrial mercury from 1929 to 1950, and recent studies have documented high levels of circulating mercury in riparian songbirds breeding below the site of contamination. Here we used two standardized immune assays, mitogen-induced swelling in response to phytohaemagglutinin (PHA) and antibody response to sheep red blood cells (SRBCs), to test for effects of mercury toxicity on the immune system of female tree swallows (Tachycineta bicolor) which feed on terrestrial and aquatic insects along the contaminated waterway. We found that females breeding at mercury-contaminated sites mounted significantly weaker PHA-induced swelling responses than those at reference sites in both years of study. However, among females on the contaminated sites, individual bloodstream mercury concentration did not predict the extent of mitogen-induced swelling. We did not detect any differences between reference and contaminated females in the strength of antibody responses to SRBCs, but sample sizes for this assay were significantly smaller. Overall, our results suggest that mercury toxicity can exert sub-lethal immunosuppression in free-living, insectivorous songbirds. The potential fitness consequences of the detected differences in immunocompetence caused by mercury toxicity warrant further study.

  11. Inhalation delivery of asthma drugs.

    Science.gov (United States)

    Matthys, H

    1990-01-01

    In the immediate future, metered-dose inhalers (MDIs) with spacers remain the aerosol application of choice for topical steroids, mainly to reduce side effects. For beta 2-agonist, anticholinergics and prophylactic drugs, MDI (with or without demand valve), dry powder inhalers (multidose inhalers), ultrasonic or jet aerosol generators (with or without mechanical breathing assistance [IPPB]) are chosen according to the preference or the ability of the patients to perform the necessary breathing maneuvers as well as the availability of different products in different countries.

  12. Methaemoglobinaemia due to amyl nitrite inhalation: a case report.

    Science.gov (United States)

    Machabert, R; Testud, F; Descotes, J

    1994-05-01

    Methaemoglobinaemia is a potential toxic effect of aliphatic nitrites which are increasingly abused by male homosexuals and drug addicts because of marked vasodilating properties ('poppers'). In most instances, severe complications were described following the ingestion of large quantities of amyl, butyl or isobutyl nitrites. A deficiency in NADH-dependent haemoglobin reductase in some patients has been noted. This is the first report of symptomatic methaemoglobinaemia following the inhalation of amyl nitrite.

  13. Inhalation Toxicology Research Institute Annual Report, 1992-1993

    Science.gov (United States)

    1993-11-01

    the following: (1) Theories implicating aluminum and other airborne, inhaled environmental toxicants as causal in Alzheimers and related diseases...parts, including the aluminum delivery tube, bottom surface, impactor cone, impaction plate (planchet), brass tube, and fluoropore backup filter, were...The assignment of the fuel element to the category of solids is valid because the fuel element is an alloy of aluminum and enriched uranium and as

  14. Mercury emission from crematoria.

    Science.gov (United States)

    Santarsiero, Anna; Settimo, Gaetano; Dell'andrea, Elena

    2006-01-01

    The purpose of this study, undertaken at a cremator representing an example of current equipment and cremation practices in use in Italy, is to assess the possible mercury emitted during cremation and substantiate the current data available. This paper reports some preliminary results concerning mercury and total particulate matter emissions during three cremation processes. The obtained results gave a mercury concentration ranging from 0.005 to 0.300 mg/m3 and a mercury emission factor ranging from 0.036 to 2.140 g/corpse cremated. The total particulate matter concentration range was 1.0 to 2.4 mg/m3.

  15. Peru Mercury Inventory 2006

    Science.gov (United States)

    Brooks, William E.; Sandoval, Esteban; Yepez, Miguel A.; Howard, Howell

    2007-01-01

    In 2004, a specific need for data on mercury use in South America was indicated by the United Nations Environmental Programme-Chemicals (UNEP-Chemicals) at a workshop on regional mercury pollution that took place in Buenos Aires, Argentina. Mercury has long been mined and used in South America for artisanal gold mining and imported for chlor-alkali production, dental amalgam, and other uses. The U.S. Geological Survey (USGS) provides information on domestic and international mercury production, trade, prices, sources, and recycling in its annual Minerals Yearbook mercury chapter. Therefore, in response to UNEP-Chemicals, the USGS, in collaboration with the Economic Section of the U.S. Embassy, Lima, has herein compiled data on Peru's exports, imports, and byproduct production of mercury. Peru was selected for this inventory because it has a 2000-year history of mercury production and use, and continues today as an important source of mercury for the global market, as a byproduct from its gold mines. Peru is a regional distributor of imported mercury and user of mercury for artisanal gold mining and chlor-alkali production. Peruvian customs data showed that 22 metric tons (t) of byproduct mercury was exported to the United States in 2006. Transshipped mercury was exported to Brazil (1 t), Colombia (1 t), and Guyana (1 t). Mercury was imported from the United States (54 t), Spain (19 t), and Kyrgyzstan (8 t) in 2006 and was used for artisanal gold mining, chlor-alkali production, dental amalgam, or transshipment to other countries in the region. Site visits and interviews provided information on the use and disposition of mercury for artisanal gold mining and other uses. Peru also imports mercury-containing batteries, electronics and computers, fluorescent lamps, and thermometers. In 2006, Peru imported approximately 1,900 t of a wide variety of fluorescent lamps; however, the mercury contained in these lamps, a minimum of approximately 76 kilograms (kg), and in

  16. Mercury Vapour Long-Lasting Exposure: Lymphocyte Muscarinic Receptors as Neurochemical Markers of Accidental Intoxication

    Directory of Open Access Journals (Sweden)

    E. Roda

    2016-01-01

    Full Text Available Introduction. Chronic poisoning may result in home setting after mercury (Hg vapours inhalation from damaged devices. We report a chronic, nonoccupational Hg poisoning due to 10-year indoor exposure to mercury spillage. Case Report. A 72-year-old man with polyneuropathy of suspected toxic origin. At hospitalization, toxicological clinical evaluations confirmed the altered neurological picture documented across the last decade. Periodic blood and urine Hg levels (BHg, UHg monitoring were performed from admission (t0, until 1 year later (t2, paralleled by blood neurochemical markers assessment, that is, lymphocytes muscarinic receptors (l-MRs. At t0: BHg and UHg were 27 and 1.4 microg/L, respectively (normal values: BHg 1–4.5; UHg 0.1–4.5, associated with l-MRs increase, 185.82 femtomoL/million lymphocytes (normal range: 8.0–16.0. At t1 (two days after DMSA-mobilization test, BHg weak reduction, paralleled by UHg 3.7-fold increase, was measured together with further l-MRs enhancement (205.43 femtomoL/million lymphocytes. At t2 (eight months after two cycles of DMSA chelating therapy ending, gradual improving of clinical manifestations was accompanied by progressive decrease of BHg and UHg (4.0 and 2.8 microg/L, resp. and peripheral l-MRs neurochemical marker (24.89 femtomoL/million lymphocytes. Conclusion. l-MRs modulatory effect supports their use as peripheral neurochemical marker in Hg poisoning diagnosis and chelation therapy monitoring.

  17. Mercury Vapour Long-Lasting Exposure: Lymphocyte Muscarinic Receptors as Neurochemical Markers of Accidental Intoxication

    Science.gov (United States)

    Roda, E.; Vecchio, S.; Apostoli, P.

    2016-01-01

    Introduction. Chronic poisoning may result in home setting after mercury (Hg) vapours inhalation from damaged devices. We report a chronic, nonoccupational Hg poisoning due to 10-year indoor exposure to mercury spillage. Case Report. A 72-year-old man with polyneuropathy of suspected toxic origin. At hospitalization, toxicological clinical evaluations confirmed the altered neurological picture documented across the last decade. Periodic blood and urine Hg levels (BHg, UHg) monitoring were performed from admission (t0), until 1 year later (t2), paralleled by blood neurochemical markers assessment, that is, lymphocytes muscarinic receptors (l-MRs). At t0: BHg and UHg were 27 and 1.4 microg/L, respectively (normal values: BHg 1–4.5; UHg 0.1–4.5), associated with l-MRs increase, 185.82 femtomoL/million lymphocytes (normal range: 8.0–16.0). At t1 (two days after DMSA-mobilization test), BHg weak reduction, paralleled by UHg 3.7-fold increase, was measured together with further l-MRs enhancement (205.43 femtomoL/million lymphocytes). At t2 (eight months after two cycles of DMSA chelating therapy ending), gradual improving of clinical manifestations was accompanied by progressive decrease of BHg and UHg (4.0 and 2.8 microg/L, resp.) and peripheral l-MRs neurochemical marker (24.89 femtomoL/million lymphocytes). Conclusion. l-MRs modulatory effect supports their use as peripheral neurochemical marker in Hg poisoning diagnosis and chelation therapy monitoring. PMID:27872646

  18. A global ocean inventory of anthropogenic mercury based on water column measurements

    NARCIS (Netherlands)

    Lamborg, C.H.; Hammerschmidt, C.R.; Bowman, K.L.; Swarr, G.J.; Munson, K.M.; Ohnemus, D.C.; Lam, P.L.; Heimbürger, L.-E.; Rijkenberg, M.J.A.; Saito, M.A.

    2014-01-01

    Mercury is a toxic, bioaccumulating trace metal whose emissions to the environment have increased significantly as a result of anthropogenic activities such as mining and fossil fuel combustion. Several recent models have estimated that these emissions have increased the oceanic mercury inventory by

  19. A global ocean inventory of anthropogenic mercury based on water column measurements

    NARCIS (Netherlands)

    Lamborg, C.H.; Hammerschmidt, C.R.; Bowman, K.L.; Swarr, G.J.; Munson, K.M.; Ohnemus, D.C.; Lam, P.L.; Heimbürger, L.-E.; Rijkenberg, M.J.A.; Saito, M.A.

    2014-01-01

    Mercury is a toxic, bioaccumulating trace metal whose emissions to the environment have increased significantly as a result of anthropogenic activities such as mining and fossil fuel combustion. Several recent models have estimated that these emissions have increased the oceanic mercury inventory by

  20. Molecular characterization of mercury resistant bacteria inhabiting polluted water bodies of different geographical locations in India

    NARCIS (Netherlands)

    Jan, A.T.; Azam, M.; Ali, A.; Haq, Q.M.

    2012-01-01

    Mercury pollution is a major environmental problem that arises as a result of natural processes as well as from anthropogenic sources. In response to toxic mercury compounds, microbes have developed astonishing array of resistance systems to detoxify them. To address this challenge, this study was a

  1. Fluticasone and Vilanterol Oral Inhalation

    Science.gov (United States)

    ... the inhaler without using your dose, you will waste the medication. The counter will count down by ... it from the foil overwrap or after every blister has been used (when the dose indicator reads ...

  2. Toxic Metals Found in E-Cigarette Liquid

    Science.gov (United States)

    ... news/fullstory_163492.html Toxic Metals Found in E-Cigarette Liquid Their presence in 5 brands studied is ... the metals end up in the aerosol that e-cigarette users inhale," said study leader Ana Maria Rule, ...

  3. Potent Inhalational Anesthetics for Dentistry.

    Science.gov (United States)

    Satuito, Mary; Tom, James

    2016-01-01

    Nitrous oxide and the volatile inhalational anesthetics have defined anxiety and pain control in both dentistry and medicine for over a century. From curious experimentation to spectacular public demonstrations, the initial work of 2 dentists, Horace Wells and William T. G. Morton, persists to this day in modern surgery and anesthesia. This article reviews the history, similarities, differences, and clinical applications of the most popular inhalational agents used in contemporary dental surgical settings.

  4. Metal mercury poisoning in two boys initially treated for brucellosis in Mashhad, Iran.

    Science.gov (United States)

    Sasan, M S; Hadavi, N; Afshari, R; Mousavi, S R; Alizadeh, A; Balali-Mood, Mahdi

    2012-02-01

    Elemental mercury (Hg) is the only metal which evaporates in room temperature and its inhalation may cause toxicity. Hg poisoning may occur by mishandling the metal, particularly in children who play with it. Wide-spectrum of the clinical presentations of chronic Hg poisoning may cause misdiagnosis, particularly when history of exposure is unknown. We report two cases of accidental Hg poisoning, which initially had been diagnosed and treated for brucellosis. The patients were two brothers (7 and 14 years old) who presented with pain in their lower extremities, sweating, salivation, weight loss, anorexia and mood changes on admission. Meticulous history taking revealed that they had played with a ball of Hg since 3 months before admission. The level of urinary Hg was 125.9 and 54.2 9 g/L in the younger and older brother, respectively (normal ≤25 g/L). The patients were successfully treated by dimercaprol and discharged in good condition 24 days after admission. These cases are being reported to emphasize the importance of acrodynia as a differential diagnosis for brucellosis in endemic areas.

  5. Evaluation of a sequential extraction process used for determining mercury binding mechanisms to coal combustion byproducts.

    Science.gov (United States)

    Noel, James D; Biswas, Pratim; Giammar, Daniel E

    2007-07-01

    Leaching of mercury from coal combustion byproducts is a concern because of the toxicity of mercury. Leachability of mercury can be assessed by using sequential extraction procedures. Sequential extraction procedures are commonly used to determine the speciation and mobility of trace metals in solid samples and are designed to differentiate among metals bound by different mechanisms and to different solid phases. This study evaluated the selectivity and effectiveness of a sequential extraction process used to determine mercury binding mechanisms to various materials. A six-step sequential extraction process was applied to laboratory-synthesized materials with known mercury concentrations and binding mechanisms. These materials were calcite, hematite, goethite, and titanium dioxide. Fly ash from a full-scale power plant was also investigated. The concentrations of mercury were measured using inductively coupled plasma (ICP) mass spectrometry, whereas the major elements were measured by ICP atomic emission spectrometry. The materials were characterized by X-ray powder diffraction and scanning electron microscopy with energy dispersive spectroscopy. The sequential extraction procedure provided information about the solid phases with which mercury was associated in the solid sample. The procedure effectively extracted mercury from the target phases. The procedure was generally selective in extracting mercury. However, some steps in the procedure extracted mercury from nontarget phases, and others resulted in mercury redistribution. Iron from hematite and goethite was only leached in the reducible and residual extraction steps. Some mercury associated with goethite was extracted in the ion exchangeable step, whereas mercury associated with hematite was extracted almost entirely in the residual step. Calcium in calcite and mercury associated with calcite were primarily removed in the acid-soluble extraction step. Titanium in titanium dioxide and mercury adsorbed onto

  6. Mercury Report-Children's exposure to elemental mercury

    Science.gov (United States)

    ... the report written? Children attending a daycare in New Jersey were exposed to elemental (metallic) mercury. The ... Mercury is also in some medical and mechanical equipment used in the home and in ... some medical and dental clinics use mercury or items that contain mercury. ...

  7. Detoxification of mercury pollutant leached from spent fluorescent lamps using bacterial strains.

    Science.gov (United States)

    Al-Ghouti, Mohammad A; Abuqaoud, Reem H; Abu-Dieyeh, Mohammed H

    2016-03-01

    The spent fluorescent lamps (SFLs) are being classified as a hazardous waste due to having mercury as one of its main components. Mercury is considered the second most toxic heavy metal (arsenic is the first) with harmful effects on animal nervous system as it causes different neurological disorders. In this research, the mercury from phosphor powder was leached, then bioremediated using bacterial strains isolated from Qatari environment. Leaching of mercury was carried out with nitric and hydrochloric acid solutions using two approaches: leaching at ambient conditions and microwave-assisted leaching. The results obtained from this research showed that microwave-assisted leaching method was significantly better in leaching mercury than the acid leaching where the mercury leaching efficiency reached 76.4%. For mercury bio-uptake, twenty bacterial strains (previously isolated and purified from petroleum oil contaminated soils) were sub-cultured on Luria Bertani (LB) plates with mercury chloride to check the bacterial tolerance to mercury. Seven of these twenty strains showed a degree of tolerance to mercury. The bio-uptake capacities of the promising strains were investigated using the mercury leached from the fluorescent lamps. Three of the strains (Enterobacter helveticus, Citrobacter amalonaticus, and Cronobacter muytjensii) showed bio-uptake efficiency ranged from 28.8% to 63.6%.

  8. Differential mercury volatilization by tobacco organs expressing a modified bacterial merA gene

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Mercury pollution is a major environmental problem accompanying industrial activities. Most of the mercury released ends up and retained in the soil as complexes of the toxic ionic mercury (Hg2+), which then can be converted by microbes into the even more toxic methylmercury which tends to bioaccumulate. Mercury detoxification of the soil can also occur by microbes converting the ionic mercury into the least toxic metallic mercury (Hg0) form, which then evaporates. The remediation potential of transgenic plants carrying the MerA gene from E. Coli encoding mercuric ion reductase could be evaluated. A modified version of the gene, optimized for plant codon preferences (merApe9, Rugh et al. 1996), was introduced into tobacco by Agrobacterium-mediated leaf disk transformation. Transgenic seeds were resistant to HgCl2 at 50 μM, and some of them (10-20%) could germinate on media containing as much as 350 μM HgCl2, while the control plants were fully inhibited or died on 50μM HgCl2. The rate of elemental mercury evolution from Hg2+ (added as HgCl2) was 5-8 times higher for transgenic plants than the control. Mercury volatilization by isolated organs standardized for fresh weight was higher (up to 5 times) in the roots than in shoots or the leaves. The data suggest that it is the root system of the transgenic plants that volatilizes most of the reduced mercury (Hg0). It also suggests that much of the mercury need not enter the vascular system to be transported to the leaves for volatilization. Transgenic plants with the merApe9 gene may be used to mercury detoxification for environmental improvement in mercury-contaminated regions more efficiently than it had been predicted based on data on volatilization of whole plants via the upper parts only (Rugh et al. 1996).

  9. Mercury Detoxification by Bacteria: Simulations of Transcription Activation and Mercury-Carbon Bond Cleavage

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hao-Bo [ORNL; Parks, Jerry M [ORNL; Johs, Alexander [ORNL; Smith, Jeremy C [ORNL

    2011-01-01

    In this chapter, we summarize recent work from our laboratory and provide new perspective on two important aspects of bacterial mercury resistance: the molecular mechanism of transcriptional regulation by MerR, and the enzymatic cleavage of the Hg-C bond in methylmercury by the organomercurial lyase, MerB. Molecular dynamics (MD) simulations of MerR reveal an opening-and-closing dynamics, which may be involved in initiating transcription of mercury resistance genes upon Hg(II) binding. Density functional theory (DFT) calculations on an active-site model of the enzyme reveal how MerB catalyzes the Hg-C bond cleavage using cysteine coordination and acid-base chemistry. These studies provide insight into the detailed mechanisms of microbial gene regulation and defense against mercury toxicity.

  10. Auto-aggressive metallic mercury injection around the knee joint: a case report

    Directory of Open Access Journals (Sweden)

    Friesenbichler Joerg

    2011-11-01

    Full Text Available Abstract Background Accidental or intentional subcutaneous and/or intramuscular injection of metallic mercury is an uncommon form of poisoning. Although it does not carry the same risk as mercury vapour inhalation, it may cause destructive early and late reactions. Case Presentation Herein we present the case of a 29-year-old male patient who developed an obsessive-compulsive disorder causing auto-aggressive behaviour with injection of elemental mercury and several other foreign bodies into the soft tissues around the left knee about 15 years before initial presentation. For clinical examination X-rays and a CT-scan of the affected area were performed. Furthermore, blood was taken to determine the mercury concentration in the blood, which showed a concentration 17-fold higher than recommended. As a consequence, the mercury depots and several foreign bodies were resected marginally. Conclusion Blood levels of mercury will decrease rapidly following surgery, especially in combination with chelating therapy. In case of subcutaneous and intramuscular injection of metallic mercury we recommend marginal or wide excision of all contaminated tissue to prevent migration of mercury and chronic inflammation. Nevertheless, prolonged clinical and biochemical monitoring should be performed for several years to screen for chronic intoxication.

  11. Inhalation a significant exposure route for chlorinated organophosphate flame retardants.

    Science.gov (United States)

    Schreder, Erika D; Uding, Nancy; La Guardia, Mark J

    2016-05-01

    Chlorinated organophosphate flame retardants (ClOPFRs) are widely used as additive flame retardants in consumer products including furniture, children's products, building materials, and textiles. Tests of indoor media in homes, offices, and other environments have shown these compounds are released from products and have become ubiquitous indoor pollutants. In house dust samples from Washington State, U.S.A., ClOPFRs were the flame retardants detected in the highest concentrations. Two ClOPFRs, tris(1,3-dichloro-2-propyl)phosphate (TDCPP or TDCIPP) and tris(2-chloroethyl)phosphate (TCEP), have been designated as carcinogens, and there is growing concern about the toxicity of the homologue tris(1-chloro-2-propyl)phosphate (TCPP or TCIPP). In response to concerns about exposure to these compounds, the European Union and a number of U.S. states have taken regulatory action to restrict their use in certain product categories. To better characterize exposure to ClOPFRs, inhalation exposure was assessed using active personal air samplers in Washington State with both respirable and inhalable particulate fractions collected to assess the likelihood particles penetrate deep into the lungs. Concentrations of ∑ClOPFRs (respirable and inhalable) ranged from 97.1 to 1190 ng m(-3) (mean 426 ng m(-3)), with TCPP detected at the highest concentrations. In general, higher levels were detected in the inhalable particulate fraction. Total intake of ClOPFRs via the inhalation exposure route was estimated to exceed intake via dust ingestion, indicating that inhalation is an important route that should be taken into consideration in assessments of these compounds.

  12. Inhalation of titanium dioxide induces endoplasmic reticulum stress-mediated autophagy and inflammation in mice.

    Science.gov (United States)

    Yu, Kyeong-Nam; Sung, Jae Hyuck; Lee, Somin; Kim, Ji-Eun; Kim, Sanghwa; Cho, Won-Young; Lee, Ah Young; Park, Soo Jin; Lim, Joohyun; Park, Changhoon; Chae, Chanhee; Lee, Jin Kyu; Lee, Jinkyu; Kim, Jun-Sung; Cho, Myung-Haing

    2015-11-01

    Titanium dioxide (TiO2) nanoparticles are widely used in cosmetics, sunscreen, electronics, drug delivery systems, and diverse bio-application fields. In the workplace, the primary exposure route for TiO2 nanoparticles is inhalation through the respiratory system. Because TiO2 nanoparticles have different physiological properties, in terms of size and bioactivity, their toxic effects in the respiratory system must be determined. In this study, to determine the toxic effect of inhaled TiO2 nanoparticles in the lung and the underlying mechanism, we used a whole-body chamber inhalation system to expose A/J mice to TiO2 nanoparticles for 28 days. During the experiments, the inhaled TiO2 nanoparticles were characterized using a cascade impactor and transmission electron microscopy. After inhalation of the TiO2 nanoparticles, hyperplasia and inflammation were observed in a TiO2 dose-dependent manner. To determine the biological mechanism of the toxic response in the lung, we examined endoplasmic reticulum (ER) and mitochondria in lung. The ER and mitochondria were disrupted and dysfunctional in the TiO2-exposed lung leading to abnormal autophagy. In summary, we assessed the potential risk of TiO2 nanoparticles in the respiratory system, which contributed to our understanding of the mechanism underlining TiO2 nanoparticle toxicity in the lung.

  13. MESSENGER: Exploring Mercury's Magnetosphere

    Science.gov (United States)

    Slavin, James A.

    2008-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. Mercury's magnetosphere is unique in many respects. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only - 1000 to 2000 km above the surface. For this reason there are no closed dri-fi paths for energetic particles and, hence, no radiation belts; the characteristic time scales for wave propagation and convective transport are short possibly coupling kinetic and fluid modes; magnetic reconnection at the dayside magnetopause may erode the subsolar magnetosphere allowing solar wind ions to directly impact the dayside regolith; inductive currents in Mercury's interior should act to modify the solar In addition, Mercury's magnetosphere is the only one with its defining magnetic flux tubes rooted in a planetary regolith as opposed to an atmosphere with a conductive ionosphere. This lack of an ionosphere is thought to be the underlying reason for the brevity of the very intense, but short lived, approx. 1-2 min, substorm-like energetic particle events observed by Mariner 10 in Mercury's magnetic tail. In this seminar, we review what we think we know about Mercury's magnetosphere and describe the MESSENGER science team's strategy for obtaining answers to the outstanding science questions surrounding the interaction of the solar wind with Mercury and its small, but dynamic magnetosphere.

  14. Mercury's shifting, rolling past

    OpenAIRE

    Trulove, Susan

    2008-01-01

    Patterns of scalloped-edged cliffs or lobate scarps on Mercury's surface are thrust faults that are consistent with the planet shrinking and cooling with time. However, compression occurred in the planet's early history and Mariner 10 images revealed decades ago that lobate scarps are among the youngest features on Mercury. Why don't we find more evidence of older compressive features?

  15. International mercury conference

    CSIR Research Space (South Africa)

    Leaner, J

    2006-10-01

    Full Text Available Mercury (Hg) affects human health and the environment, it calls for immediate action. Action is needed at local, regional and international level to reduce the risk associated with mercury, which is a global international problem, as it is a...

  16. Effects of micronutrients on metal toxicity.

    OpenAIRE

    Peraza, M A; Ayala-Fierro, F; Barber, D S; Casarez, E; Rael, L T

    1998-01-01

    There is growing evidence that micronutrient intake has a significant effect on the toxicity and carcinogenesis caused by various chemicals. This paper examines the effect of micronutrient status on the toxicity of four nonessential metals: cadmium, lead, mercury, and arsenic. Unfortunately, few studies have directly examined the effect of dietary deficiency or supplementation on metal toxicity. More commonly, the effect of dietary alteration must be deduced from the results of mechanistic st...

  17. Mercury and selenium relationship in a tropical estuarine fish

    Directory of Open Access Journals (Sweden)

    Ana Carolina Pizzochero

    2015-11-01

    Full Text Available Aquatic systems have been considered as final sinks for persistent and bioaccumulative toxicants (PBTs, such as metals and organohalogen compounds. Among the trace elements, non-essential metals deserve special attention due to their toxicity. In this context, mercury (Hg should be highlighted due to its toxic effects, which comprise neurotoxicity, nephrotoxicity, hepatotoxicity, genotoxicity, among others. Several studies have highlighted the selenium-mediated methylmercury detoxification process, via mercury selenide formation in tissues of marine vertebrates. Despite being an essential element, selenium may also be toxic in high concentrations. This study focused on Guanabara Bay (GB, a heavily polluted urban estuary in Rio de Janeiro state (Brazil, where the whitemouth croaker (Micropogonias furnieri provides a valuable fishery resource. Therefore, hepatic (Hg and Se and muscular (Hg concentrations of these elements were determined in GB whitemouth croakers. Mercury and selenium measurements were performed by cold vapor atomic absorption spectrometry (CV-AAS and electrothermal AAS (ET-AAS, respectively. Total mercury (THg concentrations in muscle (n=19 ranged from 184.9 to 858.6 (ng/g, while in liver they varied from 11.05 to 1188 (ng/g. Hepatic selenium concentrations ranged from 7820 to 40085 (ng/g. The hepatic Se:THg molar ratio ranged from 40,8 to 3102,5. The results showed a significant correlation between hepatic mercury and selenium levels, but the molar ratio suggests the absence of mercury selenide formation. Some of the Se concentrations found were above the threshold level for freshwater fish (12000 ng/g; however, it is not yet clear if these concentrations are toxic for marine fish as well. More studies are necessary for evaluating the impact of such exposure in fish from Guanabara Bay.

  18. [Overview of studies on detoxification effect of smilacis glabrae rhizoma on mercury poisoning].

    Science.gov (United States)

    Xu, Xiaofei; Chen, Hongfeng; Ye, Meina

    2012-03-01

    Mercury-containing preparations are widely used in surgery department of traditional Chinese medicine and have made remarkable achievements. But they are toxic to human kidney, nerve, immune, etc. Smilacis Glabrae Rhizoma is sweet, tasteless and neutral in nature and able to enter liver and stomach channels and detoxify mercury poisoning. This article summarizes the mercury poisoning and the detoxification effect of Smilacis Glabrae Rhizoma in ancient records, pharmaceutical studies and clinical application, in order to provide ideas and methods for the safe use of mercury-containing preparations in surgery department of traditional Chinese medicine.

  19. A review of mercury exposure among artisanal small-scale gold miners in developing countries

    DEFF Research Database (Denmark)

    Kristensen, Anders Kasper Bruun; Thomsen, Jane Frølund; Mikkelsen, Sigurd

    2014-01-01

    Extraction of gold using mercury has been a way out of poverty for millions of people in developing countries. Artisanal small-scale gold mining (ASGM) has expanded during the last decades and is often carried out under primitive conditions. Thus, workers in this industry may be exposed to high...... levels of mercury and suffer from toxic effects from mercury exposure. The objective of this review was to provide an outline of the studies available on elemental mercury exposure among artisanal small-scale gold miners....

  20. Getting Mercury out of Schools.

    Science.gov (United States)

    1999

    This guide was prepared while working with many Massachusetts schools to remove items that contain mercury and to find suitable alternatives. It contains fact sheets on: mercury in science laboratories and classrooms, mercury in school buildings and maintenance areas, mercury in the medical office and in medical technology classrooms in vocational…

  1. Possible Drawback to Gluten-Free: Toxic Metals

    Science.gov (United States)

    ... gov/news/fullstory_163630.html Possible Drawback to Gluten-Free: Toxic Metals Higher levels of arsenic, mercury ... 16, 2017 (HealthDay News) -- America's love affair with gluten-free foods may come at a cost: greater ...

  2. Selenium:Mercury Molar Ratios in Freshwater Fish from Tennessee: Individual, Species, and Geographical Variations have Implications for Management

    Science.gov (United States)

    Burger, Joanna; Gochfeld, Michael; Jeitner, C.; Donio, M.; Pittfield, T.

    2014-01-01

    Vertebrates, including humans, can experience adverse effects from mercury consumed in fish. Humans often prefer large predatory fish that bioaccumulate high mercury levels. Recent attention has focused on the role of selenium countering mercury toxicity, but there is little research on the selenium:mercury molar ratios in freshwater fish. We examine selenium:mercury molar ratios in freshwater fish from Tennessee at Poplar Creek which receives ongoing inputs of mercury from the Department of Energy’s Oak Ridge Y-12 facility. Our objective was to determine variation of the ratios within species that might affect the protectiveness of selenium against mercury toxicity. Within species, the ratio was correlated significantly and positively with fish length only for two species. There was great individual variation in the selenium:mercury molar ratio within each species, except striped bass. The lack of a clear relationship between the selenium:mercury molar ratio and fish length, and the intraspecific variation, suggests that it would be difficult to use the molar ratio in predicting either the risk from mercury toxicity or in devising consumption advisories. PMID:22456727

  3. Mercury Levels in Locally Manufactured Mexican Skin-Lightening Creams

    Directory of Open Access Journals (Sweden)

    Luz O. Leal

    2011-06-01

    Full Text Available Mercury is considered one of the most toxic elements for plants and animals. Nevertheless, in the Middle East, Asia and Latin America, whitening creams containing mercury are being manufactured and purchased, despite their obvious health risks. Due to the mass distribution of these products, this can be considered a global public health issue. In Mexico, these products are widely available in pharmacies, beauty aid and health stores. They are used for their skin lightening effects. The aim of this work was to analyze the mercury content in some cosmetic whitening creams using the cold vapor technique coupled with atomic absorption spectrometry (CV-AAS. A total of 16 skin-lightening creams from the local market were investigated. No warning information was noted on the packaging. In 10 of the samples, no mercury was detected. The mercury content in six of the samples varied between 878 and 36,000 ppm, despite the fact that the U.S. Food and Drug Administration (FDA has determined that the limit for mercury in creams should be less than 1 ppm. Skin creams containing mercury are still available and commonly used in Mexico and many developing countries, and their contents are poorly controlled.

  4. Fate and aqueous transport of mercury in light of the Clean Air Mercury Rule for coal-fired electric power plants

    Science.gov (United States)

    Arzuman, Anry

    Mercury is a hazardous air pollutant emitted to the atmosphere in large amounts. Mercury emissions from electric power generation sources were estimated to be 48 metric tons/year, constituting the single largest anthropogenic source of mercury in the U.S. Settled mercury species are highly toxic contaminants of the environment. The newly issued Federal Clean Air Mercury Rule requires that the electric power plants firing coal meet the new Maximum Achievable Mercury Control Technology limit by 2018. This signifies that all of the air-phase mercury will be concentrated in solid phase which, based on the current state of the Air Pollution Control Technology, will be fly ash. Fly ash is utilized by different industries including construction industry in concrete, its products, road bases, structural fills, monifills, for solidification, stabilization, etc. Since the increase in coal combustion in the U.S. (1.6 percent/year) is much higher than the fly ash demand, large amounts of fly ash containing mercury and other trace elements are expected to accumulate in the next decades. The amount of mercury transferred from one phase to another is not a linear function of coal combustion or ash production, depends on the future states of technology, and is unknown. The amount of aqueous mercury as a function of the future removal, mercury speciation, and coal and aquifer characteristics is also unknown. This paper makes a first attempt to relate mercury concentrations in coal, flue gas, fly ash, and fly ash leachate using a single algorithm. Mercury concentrations in all phases were examined and phase transformation algorithms were derived in a form suitable for probabilistic analyses. Such important parameters used in the transformation algorithms as Soil Cation Exchange Capacity for mercury, soil mercury selectivity sequence, mercury activity coefficient, mercury retardation factor, mercury species soil adsorption ratio, and mercury Freundlich soil adsorption isotherm

  5. Evaluation of mercury contamination in Smilax myosotiflora herbal preparations.

    Science.gov (United States)

    Ang, Hooi-Hoon; Lee, Kheng-Leng

    2007-01-01

    The DCA (Drug Control Authority) of Malaysia implemented phase 3 registration of traditional medicines in January 1992 with special emphasis on the quality, efficacy, and safety of all dosage forms of these medicines. For this reason, a total of 100 herbal products containing Smilax myosotiflora were purchased in the Malaysian market and analyzed for mercury content, as mercury is a recognized reproductive toxicant. The products were analyzed using cold vapor atomic absorption spectrophotometry. It was found that 89% of the above products do not exceed 0.5 ppm of mercury. Heavy metal poisoning such as mercury has been associated with traditional medicines. Therefore, it is important that doctors and health care practitioners are aware of these risks and finding ways to minimize them, including questions pertaining to the use of these remedies during the routine taking of a patient's history.

  6. Characterizing dry deposition of mercury in urban runoff

    Science.gov (United States)

    Fulkerson, M.; Nnadi, F.N.; Chasar, L.S.

    2007-01-01

    Stormwater runoff from urban surfaces often contains elevated levels of toxic metals. When discharged directly into water bodies, these pollutants degrade water quality and impact aquatic life and human health. In this study, the composition of impervious surface runoff and associated rainfall was investigated for several storm events at an urban site in Orlando, Florida. Total mercury in runoff consisted of 58% particulate and 42% filtered forms. Concentration comparisons at the start and end of runoff events indicate that about 85% of particulate total mercury and 93% of particulate methylmercury were removed from the surface before runoff ended. Filtered mercury concentrations showed less than 50% reduction of both total and methylmercury from first flush to final flush. Direct comparison between rainfall and runoff at this urban site indicates dry deposition accounted for 22% of total inorganic mercury in runoff. ?? 2007 Springer Science+Business Media B.V.

  7. Mercury and selenium in American White Pelicans breeding at Pyramid Lake, Nevada

    Science.gov (United States)

    Wiemeyer, Stanley N.; Miesner, J.F.; Tuttle, P.L.; Murphy, E.C.; Sileo, L.; Withers, D.

    2007-01-01

    American White Pelicans (Pelecanus erythrorhynchos) that breed on Anaho Island, Pyramid Lake, Nevada, are potentially exposed to a variety of contaminants. Therefore, the reproductive success of this colony was monitored in 1996 and eggs, blood and feathers from nestlings, livers from adults and nestlings, regurgitated fish from nestlings, and fish from representative feeding areas were collected and analyzed for mercury and selenium to determine exposure to the pelicans and sources of contamination. Additional samples were collected and analyzed in 1988, 1992, and 2004. Reproductive success at the Anaho Island colony was normal in 1996 based on hatching rates of eggs (???75% in undisturbed areas) and survival of nestlings. Mercury and selenium concentrations in eggs were generally below known effect levels and did not appear to have an adverse impact on hatching success. Mercury and selenium concentrations in fish ranged widely, with mercury of greatest concern. Microscopic lesions characteristic of mercury toxicity were absent in pre-fledging nestlings in 1996. Some adult pelicans had elevated mercury concentrations in their livers; however, the potential toxic effects were difficult to evaluate because of probable demethylation of mercury, thereby possibly providing protection from toxicity. Exposure of pelicans to mercury varied among years, most likely in relation to wet-dry cycles and available feeding areas.

  8. Seasonal Variations of Mercury Levels in Selected Medicinal Plants Originating from Poland.

    Science.gov (United States)

    Ordak, M; Wesolowski, M; Radecka, I; Muszynska, E; Bujalska-Zazdrozny, M

    2016-10-01

    The presence of mercury in the living cells may be caused by environmental pollution with this element, which is referred to as a toxic xenobiotic. Many literature reports have provided evidence for toxic effects of low levels of mercury in the human body. Therefore, it seems essential to investigate mercury content in food and in natural environment, particularly its seasonal variations. The objective of this study was to determine trace amounts of mercury in 45 samples of 20 medicinal plant species collected in northern Poland, in various seasons of the year, i.e., in autumn 2012 and then spring 2013. The results obtained showed that the levels of mercury in the herbs were lower in spring (3.66-34.89 ng/g) than in autumn (4.55-81.54 ng/g). The statistically significant correlation (p mercury in herbs collected in spring and autumn indicates hazardous accumulation of the element in plants in autumn. The highest levels of mercury were found in leaves and plants growing in the vicinity of busy streets. Perennials plants have a significantly higher mercury levels as compared to those of monocarpic plants. Furthermore, commonly used herbal plants have a significantly higher mercury levels as compared to those less common.

  9. Depth profiles of lithogenic and anthropogenic mercury in the sediments from Thane Creek, Mumbai, India

    Institute of Scientific and Technical Information of China (English)

    SKSAHU; RCBHANGARE; M TIWARI; PYAJMAL; GGPANDIT

    2014-01-01

    Mercury (Hg) is well known as one of the most toxic elements to man. The coastal environments adjacent to industrial areas are reported to often be contaminated with mercury. Mercury becomes more toxic in the form of methylmercury (Me-Hg) which is converted from inorganic mercury in aqueous systems by microbial activity and can bio-magnify through the food chain. A simple method for the determination of total mercury and methylmercury in sediments was optimized by slightly modifying an old method using the direct mercury analyzer technique. Core sediment samples from Thane Creek, Mumbai, India were collected and analysed for total mercury and methylmercury. The Hg concentration in the creek varied between 0.54 to 16.03 µg g-1 while Me-Hg concentrations ranged between 0.04 to 1.07 µg g-1. In surface sediment, mercury concentrations ranged from 4.33 µg g-1 to 12.16µg g-1. Total organic carbon content was found to be around 2 percent in different layers of the sediments. The enrichment factors, which indicate the extent of pollution in sediments, were estimated to range from 26 to 50 at different locations in the creek. Lithogenic and anthropogenic concentrations of mercury in the creek were also determined to compare the impact of anthropogenic and natural sources. Anthropogenic inventories were about 5-70 times more in concentration than the lithogenic in the different core sediments.

  10. Conceptual studies for a mercury target circuit

    Energy Technology Data Exchange (ETDEWEB)

    Sigg, B. [ETH Nuclear Engineering Lab., Villigen (Switzerland)

    1996-06-01

    For the now favored target design of the European Spallation Source project, i.e. the version using mercury as target material, a basic concept of the primary system has been worked out. It does not include a detailed design of the various components of the target circuit, but tries to outline a feasible solution for the system. Besides the removal of the thermal power of about 3MW produced in the target by the proton beam, the primary system has to satisfy a number of other requirements related to processing, safety, and operation. The basic proposal uses an electromagnetic pump and a mercury-water intermediate heat excanger, but other alternatives are also being discussed. Basic safety requirements, i.e. protection against radiation and toxic mercury vapours, are satisfied by a design using an air-tight primary system containment, double-walled tubes in the intermediate heat exchanger, a fail-safe system for decay heat removal, and a remote handling facility for the active part of the system. Much engineering work has still to be done, because many details of the design of the mercury and gas processing systems remain to be clarified, the thermal-hydraulic components need further optimisation, the system for control and instrumentation is only known in outline and a through safety analysis will be required.

  11. Mercury speciation by CE: an update.

    Science.gov (United States)

    Kubán, Petr; Pelcová, Pavlína; Margetínová, Jana; Kubán, Vlastimil

    2009-01-01

    This review provides an update on mercury speciation by CE. It includes a brief discussion on physicochemical properties, toxicity and transformation pathways of mercury species (i.e. methyl-, ethyl-, phenyl- and inorganic mercury) and outlines recent trends in Hg speciation by CE. CE is presented as a complementary technique to chromatographic separation techniques, especially in cases when speed, high efficiency and low sample volumes are required. The development of suitable sample preconcentration/isolation (sample stacking, ion exchange, liquid-liquid-liquid extraction, dual-cloud point extraction) to achieve low LODs for analysis of trace concentrations of mercury species in real samples is emphasized. Hyphenation of CE to element specific detectors (i.e. electrothermal atomic absorption spectrometry, atomic fluorescence spectrometry, inductively coupled plasma-optical emission spectrometry, inductively coupled plasma-mass spectrometry) is discussed as well as a potential of CE in interaction studies that may provide useful information on interaction of various Hg species with selected bio-macromolecules.

  12. Mercury's Dynamic Magnetic Tail

    Science.gov (United States)

    Slavin, James A.

    2010-01-01

    The Mariner 10 and MESSENGER flybys of Mercury have revealed a magnetosphere that is likely the most responsive to upstream interplanetary conditions of any in the solar system. The source of the great dynamic variability observed during these brief passages is due to Mercury's proximity to the Sun and the inverse proportionality between reconnection rate and solar wind Alfven Mach number. However, this planet's lack of an ionosphere and its small physical dimensions also contribute to Mercury's very brief Dungey cycle, approx. 2 min, which governs the time scale for internal plasma circulation. Current observations and understanding of the structure and dynamics of Mercury's magnetotail are summarized and discussed. Special emphasis will be placed upon such questions as: 1) How much access does the solar wind have to this small magnetosphere as a function of upstream conditions? 2) What roles do heavy planetary ions play? 3) Do Earth-like substorms take place at Mercury? 4) How does Mercury's tail respond to extreme solar wind events such coronal mass ejections? Prospects for progress due to advances in the global magnetohydrodynamic and hybrid simulation modeling and the measurements to be taken by MESSENGER after it enters Mercury orbit on March 18, 2011 will be discussed.

  13. Mercury's Protoplanetary Mass

    CERN Document Server

    Herndon, J M

    2004-01-01

    Major element fractionation among chondrites has been discussed for decades as ratios relative to Si or Mg. Recently, by expressing ratios relative to Fe, I discovered a new relationship admitting the possibility that ordinary chondrite meteorites are derived from two components, a relatively oxidized and undifferentiated, primitive component and a somewhat differentiated, planetary component, with oxidation state like the highly reduced enstatite chondrites, which I suggested was identical to Mercury's complement of lost elements. Here, on the basis of that relationship, I derive expressions, as a function of the mass of planet Mercury and the mass of its core, to estimate the mass of Mercury's lost elements, the mass of Mercury's alloy and rock protoplanetary core, and the mass of Mercury's gaseous protoplanet. Although Mercury's mass is well known, its core mass is not, being widely believed to be in the range of 70-80 percent of the planet mass. For a core mass of 75 percent, the mass of Mercury's lost el...

  14. Final disposal options for mercury/uranium mixed wastes from the Oak Ridge Reservation

    Energy Technology Data Exchange (ETDEWEB)

    Gorin, A.H.; Leckey, J.H.; Nulf, L.E.

    1994-08-29

    Laboratory testing was completed on chemical stabilization and physical encapsulation methods that are applicable (to comply with federal and state regulations) to the final disposal of both hazardous and mixed hazardous elemental mercury waste that is in either of the following categories: (1) waste generated during decontamination and decommissioning (D and D) activities on mercury-contaminated buildings, such as Building 9201-4 at the Oak Ridge Y-12 Plant, or (2) waste stored and regulated under either the Federal Facilities Compliance Agreement or the Federal Facilities Compliance Act. Methods were used that produced copper-mercury, zinc-mercury, and sulfur-mercury materials at room temperature by dry mixing techniques. Toxicity Characteristic Leaching Procedure (TCLP) results for mercury on batches of both the copper-mercury and the sulfur-mercury amalgams consistently produced leachates with less than the 0.2-mg/L Resource Conservation and Recovery Act (RCRA) regulatory limit for mercury. The results clearly showed that the reaction of mercury with sulfur at room temperature produces black mercuric sulfide, a material that is well suited for land disposal. The results also showed that the copper-mercury and zinc-mercury amalgams had major adverse properties that make them undesirable for land disposal. In particular, they reacted readily in air to form oxides and liberate elemental mercury. Another major finding of this study is that sulfur polymer cement is potentially useful as a physical encapsulating agent for mercuric sulfide. This material provides a barrier in addition to the chemical stabilization that further prevents mercury, in the form of mercuric sulfide, from migrating into the environment.

  15. Analysis of gas-phase mercury sorption with coke and lignite dust

    Directory of Open Access Journals (Sweden)

    Marczak Marta

    2017-01-01

    Full Text Available In recent years the problem of mercury emission became a widely discussed topic. Its high impact is caused by its toxicity and ability to accumulate in living organisms, properties that justified the United States Environmental Protection Agency (US EPA to classify mercury as hazardous pollutant. The problem of mercury emission is crucial for countries like Poland, where the most of the emission is caused by coaldepended energy sector. Current technology of mercury removal utilizes adsorption of mercury on the surface of activated carbon. Due to high price of activated carbon, this technological approach seems to be uneconomical and calls for cheaper alternative. One possible solution can be usage of other sorptive materials obtained from thermal processes like coke production. Example of such material is coke dust obtained from dry quenching of coke. The aim of this work was to analyse the sorption potential of lignite and coke dust and determine parameters influencing mercury behaviour during combustion.

  16. Review: Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops

    Institute of Scientific and Technical Information of China (English)

    ISLAM Ejaz ul; YANG Xiao-e; HE Zhen-li; MAHMOOD Qaisar

    2007-01-01

    Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants,particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary

  17. Mercury analysis in hair

    DEFF Research Database (Denmark)

    Esteban, Marta; Schindler, Birgit K; Jiménez-Guerrero, José A

    2015-01-01

    Human biomonitoring (HBM) is an effective tool for assessing actual exposure to chemicals that takes into account all routes of intake. Although hair analysis is considered to be an optimal biomarker for assessing mercury exposure, the lack of harmonization as regards sampling and analytical...... assurance program (QAP) for assessing mercury levels in hair samples from more than 1800 mother-child pairs recruited in 17 European countries. To ensure the comparability of the results, standard operating procedures (SOPs) for sampling and for mercury analysis were drafted and distributed to participating...

  18. Thallium Mercury Laser Development.

    Science.gov (United States)

    1980-04-17

    AD-A9 840 WESTINGHOUSE RESEARCH AND DEVELOPMENT CENTER PITTSBU--ETC F/A 20/5 THALLIUM MERCURY LASER DEVELOPMENT .(U) APR 80 C S LIU, D W FELDMAN, J L...PACK NO001I78-C-0131 lIlrt A nEQE-WOTFX-R NL THALLIUM MERCURY LASER DEVELOPMENT C. S. Liu, D. W. Feldman and J. L. Pack FINAL REPORT (PHASE II...PERIOD COVERED Thallium Mercury Laser Development -T- Final Report (Phase II) Feb. 1, 1979 to Jan. 31, 1980 77a. w-atF. -REPORT NUMBER _,___C2-OTEX

  19. Bioavailability and Methylation Potential of Mercury Sulfides in Sediments

    Science.gov (United States)

    2014-08-01

    the aquatic environment is a critical step towards accumulation of this toxic metal in the aquatic food chain. MeHg is produced in the environment...much more abundant than mercury (e.g. iron, aluminum, manganese , titanium, zinc). Nanoparticles and polynuclear clusters of metal sulfides such as...trace metal bioavailability and toxicity has yet to be fully realized. Our findings provide a new approach that may be applied to other metal-sulfide

  20. Nanotechnology-based inhalation treatments for lung cancer: state of the art

    Science.gov (United States)

    Ahmad, Javed; Akhter, Sohail; Rizwanullah, Md; Amin, Saima; Rahman, Mahfoozur; Ahmad, Mohammad Zaki; Rizvi, Moshahid Alam; Kamal, Mohammad A; Ahmad, Farhan Jalees

    2015-01-01

    Considering the challenges associated with conventional chemotherapy, targeted and local delivery of chemotherapeutics via nanoparticle (NP) carriers to the lungs is an emerging area of interest. Recent studies and growing clinical application in cancer nanotechnology showed the huge potential of NPs as drug carriers in cancer therapy, including in lung carcinoma for diagnosis, imaging, and theranostics. Researchers have confirmed that nanotechnology-based inhalation chemotherapy is viable and more effective than conventional chemotherapy, with lesser side effects. Recently, many nanocarriers have been investigated, including liposomes, polymeric micelles, polymeric NPs, solid lipid NPs, and inorganic NPs for inhalation treatments of lung cancer. Yet, the toxicity of such nanomaterials to the lungs tissues and further distribution to other organs due to systemic absorption on inhalation delivery is a debatable concern. Here, prospect of NPs-based local lung cancer targeting through inhalation route as well as its associated challenges are discussed. PMID:26640374

  1. Elevated mercury exposure in communities living alongside the Inanda Dam, South Africa.

    Science.gov (United States)

    Papu-Zamxaka, Vathiswa; Mathee, Angela; Harpham, Trudy; Barnes, Brendon; Röllin, Halina; Lyons, Michal; Jordaan, Wikus; Cloete, Marthinus

    2010-02-01

    Mercury is a persistent heavy metal that has been associated with damage to the central nervous system, including hearing and speech impairment, visual constriction and loss of muscle control. In aquatic environments mercury may be methylated to its most toxic form, methyl-mercury. In 1990 concerns were raised over mercury contamination in the vicinity of a mercury processing plant in KwaZulu-Natal, South Africa. Mercury waste was reported to have been discharged into the Mngceweni River, situated in close proximity to the plant. The Mngceweni River joins the uMgeni River, which in turn flows into the Inanda Dam, along the banks of which several villages are located. This study evaluated the mercury levels in river and dam sediments, fish from the Inanda Dam and hair samples collected from residents of three villages along the banks of the Inanda Dam. The study results showed that 50% of the fish samples and 17% of hair samples collected from villagers had mercury concentrations that exceeded guideline levels of the World Health Organization. Mercury concentrations in 62% of the river sediment samples collected in close proximity to the former mercury processing plant exceeded the level at which remedial action is required according to legislation in the Netherlands. These preliminary findings give reasons for concern and should be used as a baseline for further investigations.

  2. Occupational Exposure to Mercury among Workers in a Fluorescent Lamp Factory, Quisna Industrial Zone, Egypt

    Directory of Open Access Journals (Sweden)

    HK Allam

    2013-07-01

    Full Text Available Background: With the fast growth in the market of fluorescent lamps, particularly compact fluorescent light, the associated risk of mercury exposure, which is an essential component in all types of fluorescent lamps, has received increasing public attention worldwide. Even low doses of mercury are toxic.Objective: To study the health consequences of occupational exposure to mercury in workers of a fluorescent lamp factory.Methods: In a cross-sectional study 138 workers of a florescent lamp factory and 151 people who had no occupational exposure to mercury (the comparison group were studied. Environmental study of mercury and noise levels was done. For all participants a neurobehavioral test battery was administered, spirometry was performed and air conduction audiometry was done. Urinary mercury level was also measured for all participants.Results: Prominent symptoms among workers exposed to mercury included tremors, emotional lability, memory changes, neuromuscular changes, and performance deficits in tests of cognitive function. Among the exposed group, the mean urinary mercury level was significantly higher in those who had personality changes or had manifestations of mercury toxicity. With increasing duration of employment and urinary mercury level, the performance of participants in neurobehavioral test battery and spirometric parameters deteriorated.Conclusion: Neurobehavioral test battery must be used for studying subclinical central nervous system dysfunction in those with chronic exposure to mercury. The test is especially useful for evaluating the severity of mercury effects in epidemiological studies. This study also reinforces the need for effective preventive programs for florescent lamp industry workplaces especially in developing countries with the lowest unhygienic work conditions.

  3. Know How to Use Your Asthma Inhaler

    Medline Plus

    Full Text Available ... KB] Using a metered dose inhaler one to two inches from mouth Your browser does not support iframes Using a metered dose inhaler one to two inches from mouth [PDF - 356 KB] Your browser ...

  4. Inhalant Abuse: Is Your Child at Risk?

    Science.gov (United States)

    ... can be valuable as well. With help, your child can end inhalant abuse and learn how to make healthy choices for a lifetime. References Baydala L. Inhalant abuse. Paediatrics and Child Health. 2010;15:443. Results from the 2013 ...

  5. Recovery of mercury from mercury compounds via electrolytic methods

    Science.gov (United States)

    Grossman, M.W.; George, W.A.

    1989-11-07

    A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg[sub 2]Cl[sub 2] employing as the electrolyte solution a mixture of HCl and H[sub 2]O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H[sub 2]O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds. 3 figs.

  6. Mercury cycling in terrestrial watersheds

    Science.gov (United States)

    Shanley, James B.; Bishop, Kevin; Banks, Michael S.

    2012-01-01

    This chapter discusses mercury cycling in the terrestrial landscape, including inputs from the atmosphere, accumulation in soils and vegetation, outputs in streamflow and volatilization, and effects of land disturbance. Mercury mobility in the terrestrial landscape is strongly controlled by organic matter. About 90% of the atmospheric mercury input is retained in vegetation and organic matter in soils, causing a buildup of legacy mercury. Some mercury is volatilized back to the atmosphere, but most export of mercury from watersheds occurs by streamflow. Stream mercury export is episodic, in association with dissolved and particulate organic carbon, as stormflow and snowmelt flush organic-rich shallow soil horizons. The terrestrial landscape is thus a major source of mercury to downstream aquatic environments, where mercury is methylated and enters the aquatic food web. With ample organic matter and sulfur, methylmercury forms in uplands as well—in wetlands, riparian zones, and other anoxic sites. Watershed features (topography, land cover type, and soil drainage class) are often more important than atmospheric mercury deposition in controlling the amount of stream mercury and methylmercury export. While reductions in atmospheric mercury deposition may rapidly benefit lakes, the terrestrial landscape will respond only over decades, because of the large stock and slow turnover of legacy mercury. We conclude with a discussion of future scenarios and the challenge of managing terrestrial mercury.

  7. Hazard identification of inhaled nanomaterials: making use of short-term inhalation studies.

    Science.gov (United States)

    Klein, Christoph L; Wiench, Karin; Wiemann, Martin; Ma-Hock, Lan; van Ravenzwaay, Ben; Landsiedel, Robert

    2012-07-01

    A major health concern for nanomaterials is their potential toxic effect after inhalation of dusts. Correspondingly, the core element of tier 1 in the currently proposed integrated testing strategy (ITS) is a short-term rat inhalation study (STIS) for this route of exposure. STIS comprises a comprehensive scheme of biological effects and marker determination in order to generate appropriate information on early key elements of pathogenesis, such as inflammatory reactions in the lung and indications of effects in other organs. Within the STIS information on the persistence, progression and/or regression of effects is obtained. The STIS also addresses organ burden in the lung and potential translocation to other tissues. Up to now, STIS was performed in research projects and routine testing of nanomaterials. Meanwhile, rat STIS results for more than 20 nanomaterials are available including the representative nanomaterials listed by the Organization for Economic Cooperation and Development (OECD) working party on manufactured nanomaterials (WPMN), which has endorsed a list of representative manufactured nanomaterials (MN) as well as a set of relevant endpoints to be addressed. Here, results of STIS carried out with different nanomaterials are discussed as case studies. The ranking of different nanomaterials potential to induce adverse effects and the ranking of the respective NOAEC are the same among the STIS and the corresponding subchronic and chronic studies. In another case study, a translocation of a coated silica nanomaterial was judged critical for its safety assessment. Thus, STIS enables application of the proposed ITS, as long as reliable and relevant in vitro methods for the tier 1 testing are still missing. Compared to traditional subacute and subchronic inhalation testing (according to OECD test guidelines 412 and 413), STIS uses less animals and resources and offers additional information on organ burden and progression or regression of potential effects.

  8. Toxic leucoencephalopathy after 'chasing the dragon'.

    Science.gov (United States)

    Singh, Rajinder; Saini, Monica

    2015-06-01

    Toxic leucoencephalopathy (TLE) is a rare neurological complication of heroin abuse. 'Chasing the dragon' is an inhalational mode of heroin abuse that originated in Southeast Asia. Intriguingly, no cases of TLE have been reported from this region, although the inhalational mode of heroin abuse is common. We herein report the case of a middle-aged man with a history of polysubstance abuse who presented with progressive neurological symptoms and progressed to an uncommunicative state. While the initial impression was that of iatrogenic parkinsonism, diffuse leucoencephalopathy with sparing of the cerebellum was noted on magnetic resonance imaging. In view of his history of inhalational heroin abuse close to the onset of the neurological symptoms, a diagnosis of TLE was made. No clinical improvement was noted with administration of a dopaminergic agent. This is the first known case of delayed TLE following heroin inhalation from Southeast Asia with the unusual feature of cerebellar sparing.

  9. Mercury CEM Calibration

    Energy Technology Data Exchange (ETDEWEB)

    John F. Schabron; Joseph F. Rovani; Susan S. Sorini

    2007-03-31

    The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005, requires that calibration of mercury continuous emissions monitors (CEMs) be performed with NIST-traceable standards. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The traceability protocol will be written by EPA. Traceability will be based on the actual analysis of the output of each calibration unit at several concentration levels ranging from about 2-40 ug/m{sup 3}, and this analysis will be directly traceable to analyses by NIST using isotope dilution inductively coupled plasma/mass spectrometry (ID ICP/MS) through a chain of analyses linking the calibration unit in the power plant to the NIST ID ICP/MS. Prior to this project, NIST did not provide a recommended mercury vapor pressure equation or list mercury vapor pressure in its vapor pressure database. The NIST Physical and Chemical Properties Division in Boulder, Colorado was subcontracted under this project to study the issue in detail and to recommend a mercury vapor pressure equation that the vendors of mercury vapor pressure calibration units can use to calculate the elemental mercury vapor concentration in an equilibrium chamber at a particular temperature. As part of this study, a preliminary evaluation of calibration units from five vendors was made. The work was performed by NIST in Gaithersburg, MD and Joe Rovani from WRI who traveled to NIST as a Visiting Scientist.

  10. Cutaneous mercury granuloma

    OpenAIRE

    Kalpana A Bothale; Mahore, Sadhana D.; Sushil Pande; Trupti Dongre

    2013-01-01

    Cutaneous mercury granuloma is rarely encountered. Clinically it may pose difficulty in diagnosis. Here, we report a 23-year-old male presented with erythematous, nodular lesions over the forearm and anterior aspect of chest wall. Metallic mercury in tissue sections appear as dark black, opaque, spherical globules of varying size and number. They are surrounded by granulomatous foreign-body reaction. It is composed of foreign body giant cells and mixed inflammatory infiltrate composed of hist...

  11. Blood serum mercury test report.

    Science.gov (United States)

    Vandenberge, J; Moodie, A S; Keller, R E

    1977-06-01

    A clinical blood serum mercury test of 111 dentists and auxiliaries revelaed that more than 50% had above normal serum mercury levels. This study showed that there may be a mercury health hazard in some dental environments. Acute mercury poisoning may be corrected simply by removing the cause, but long-term chronic effects are not known. Frequent screening of offices and personnel is advised. Experience reported here indicates that large amounts of mercury vapor are emitted when an amalgam carrier is heated over a flame ot dislodge particles, and also, that water-covered amalgam scrap relesases mercury vapor.

  12. To Mercury dynamics

    Science.gov (United States)

    Barkin, Yu. V.; Ferrandiz, J. M.

    Present significance of the study of rotation of Mercury considered as a core-mantle system arises from planned Mercury missions. New high accurate data on Mercury's structure and its physical fields are expected from BepiColombo mission (Anselmi et al., 2001). Investigation of resonant rotation of Mercury, begun by Colombo G. (1966), will play here main part. New approaches to the study of Mercury dynamics and the construction of analytical theory of its resonant rotation are suggested. Within these approaches Mercury is considered as a system of two non-spherical interacting bodies: a core and a mantle. The mantle of Mercury is considered as non-spherical, rigid (or elastic) layer. Inner shell is a liquid core, which occupies a large ellipsoidal cavity of Mercury. This Mercury system moves in the gravitational field of the Sun in resonant traslatory-rotary regime of the resonance 3:2. We take into account only the second harmonic of the force function of the Sun and Mercury. For the study of Mercury rotation we have been used specially designed canonical equations of motion in Andoyer and Poincare variables (Barkin, Ferrandiz, 2001), more convenient for the application of mentioned methods. Approximate observational and some theoretical evaluations of the two main coefficients of Mercury gravitational field J_2 and C22 are known. From observational data of Mariner-10 mission were obtained some first evaluations of these coefficients: J_2 =(8± 6)\\cdot 10-5(Esposito et al., 1977); J_2 =(6± 2)\\cdot 10-5and C22 =(1.0± 0.5)\\cdot 10-5(Anderson et al., 1987). Some theoretical evaluation of ratio of these coefficients has been obtained on the base of study of periodic motions of the system of two non-spherical gravitating bodies (Barkin, 1976). Corresponding values of coefficients consist: J_2 =8\\cdot 10-5and C22 =0.33\\cdot 10-5. We have no data about non-sphericity of inner core of Mercury. Planned missions to Mercury (BepiColombo and Messenger) promise to

  13. [Severe burns related to steam inhalation therapy].

    Science.gov (United States)

    Belmonte, J A; Domínguez-Sampedro, P; Pérez, E; Suelves, J M; Collado, J M

    2015-02-01

    Despite lack of proven effectiveness and its potential to cause severe burns, steam inhalation therapy (SIT) is still used as a treatment for benign respiratory conditions. To characterize cases of burns related to steam inhalation therapy (BRSIT) in order to formulate appropriate preventive criteria. A review was conducted on cases of BRSIT admitted to a Burns Unit between 2006 and 2012, analysing epidemiological data, clinical aspects, severity and course. A total of 530 patients were admitted; 375 (70%) with scalds, and 15 with BRSIT (2.8% of burns; 4% of scalds). SIT was indicated in most cases for mild upper airway infections. The median age of patients was 7 years (2.5m-14 y). The burned area (BA) was ≥10% in 60% of cases (max. BA 22%). Injuries involved trunk, genital area, and extremities; only in one case was the face affected. The mean hospital length-of-stay was 14 days (3-30 d). Five patients (33%) were admitted to the PICU, most of them (60%) younger than 3 years. Eight patients (53%) underwent surgical treatment (skin grafting). In a 12-year-old patient whooping cough was diagnosed in the Burns Unit, and a 2.5-year-old patient developed staphylococcal toxic shock syndrome. No patient died. The final course was satisfactory in all patients. BRSIT can be severe and cause significant use of health resources. Professionals caring for children, particularly paediatricians, should seriously consider their prevention, avoiding treatments with SIT, and educating parents in order not to use it on their own. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  14. Parental Influence on Inhalant Use

    Science.gov (United States)

    Baltazar, Alina; Hopkins, Gary; McBride, Duane; Vanderwaal, Curt; Pepper, Sara; Mackey, Sarah

    2013-01-01

    The purpose of this article is to examine the dynamics of the relationship between parents and their adolescent children and their association with lifetime and past-month inhalant usage. The population studied was seventh- through ninth-grade students in rural Idaho (N = 570). The authors found a small, but consistent, significant inverse…

  15. The potential risk of environmental contamination by mercury contained in Polish coal mining waste

    Directory of Open Access Journals (Sweden)

    Tomasz Antoszczyszyn

    2016-01-01

    Full Text Available The paper contains reference literature analysis concerning mercury content in Polish bituminous coal and post-mining waste as well as the impact of mercury content on the environment. The aim of the paper was to determine the occurrence of the risk of contamination of the environment with mercury compounds found in demolition bituminous coal landfills. Mercury, due to its toxic properties has been classified among the most dangerous substances to human health. There are three groups of sources of mercury release into the environment: natural, anthropogenic and remission. Coal mining, its processing and use in the energy sector has the greatest relevance regarding the pollution of the environment with mercury compounds in Poland. A review of reference literature shows that the average content of mercury in Polish bituminous coal varies within a wide range of 41–399 ppb, which is conditional on the origin, age and type of coal. The production of coal has led to a number of facilities in the form of structurally and age-varied landfills, heaps and mining waste dumps. The content of mercury in post-mining waste is in the range from approximately 55 to 380 ppb. The problem of environmental contamination with mercury has attracted considerable interest due to the effects that its concentration have in the biosphere. On the basis of the existing data it has been found that the content of mercury in soils in areas degraded by mining and processing of coal is even 10–16 times higher, compared to the geochemical background. It is necessary to conduct research in this area due to the limited results of research on mercury content in deposited waste from the preparation and flotation of Polish bituminous coals and the potential harmful effect of mercury on the environment. The paper is dedicated to the mercury content in waste from the extraction and processing of bituminous coal.

  16. A new mercury-accumulating Mucor hiemalis strain EH8 from cold sulfidic spring water biofilms.

    Science.gov (United States)

    Hoque, Enamul; Fritscher, Johannes

    2016-10-01

    Here, we report about a unique aquatic fungus Mucor hiemalisEH8 that can remove toxic ionic mercury from water by intracellular accumulation and reduction into elemental mercury (Hg(0) ). EH8 was isolated from a microbial biofilm grown in sulfidic-reducing spring water sourced at a Marching's site located downhill from hop cultivation areas with a history of mercury use. A thorough biodiversity survey and mercury-removal function analyses were undertaken in an area of about 200 km(2) in Bavaria (Germany) to find the key biofilm and microbe for mercury removal. After a systematic search using metal removal assays we identified Marching spring's biofilm out of 18 different sulfidic springs' biofilms as the only one that was capable of removing ionic Hg from water. EH8 was selected, due to its molecular biological identification as the key microorganism of this biofilm with the capability of mercury removal, and cultivated as a pure culture on solid and in liquid media to produce germinating sporangiospores. They removed 99% of mercury from water within 10-48 h after initial exposure to Hg(II). Scanning electron microscopy demonstrated occurrence of intracellular mercury in germinating sporangiospores exposed to mercury. Not only associated with intracellular components, but mercury was also found to be released and deposited as metallic-shiny nanospheres. Electron-dispersive x-ray analysis of such a nanosphere confirmed presence of mercury by the HgMα peak at 2.195 keV. Thus, a first aquatic eukaryotic microbe has been found that is able to grow even at low temperature under sulfur-reducing conditions with promising performance in mercury removal to safeguard our environment from mercury pollution. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  17. Demonstration of New Technologies Required for the Treatment of Mixed Waste Contaminated with {ge}260 ppm Mercury

    Energy Technology Data Exchange (ETDEWEB)

    Morris, M.I.

    2002-02-06

    The Resource Conservation and Recovery Act (RCRA) defines several categories of mercury wastes, each of which has a defined technology or concentration-based treatment standard, or universal treatment standard (UTS). RCRA defines mercury hazardous wastes as any waste that has a TCLP value for mercury of 0.2 mg/L or greater. Three of these categories, all nonwastewaters, fall within the scope of this report on new technologies to treat mercury-contaminated wastes: wastes as elemental mercury; hazardous wastes with less than 260 mg/kg [parts per million (ppm)] mercury; and hazardous wastes with 260 ppm or more of mercury. While this report deals specifically with the last category--hazardous wastes with 260 ppm or more of mercury--the other two categories will be discussed briefly so that the full range of mercury treatment challenges can be understood. The treatment methods for these three categories are as follows: Waste as elemental mercury--RCRA identifies amalgamation (AMLGM) as the treatment standard for radioactive elemental mercury. However, radioactive mercury condensates from retorting (RMERC) processes also require amalgamation. In addition, incineration (IMERC) and RMERC processes that produce residues with >260 ppm of radioactive mercury contamination and that fail the RCRA toxicity characteristic leaching procedure (TCLP) limit for mercury (0.20 mg/L) require RMERC, followed by AMLGM of the condensate. Waste with <260 ppm mercury--No specific treatment method is specified for hazardous wastes containing <260 ppm. However, RCRA regulations require that such wastes (other than RMERC residues) that exceed a TCLP mercury concentration of 0.20 mg/L be treated by a suitable method to meet the TCLP limit for mercury of 0.025 mg/L. RMERC residues must meet the TCLP value of {ge}0.20 mg/L, or be stabilized and meet the {ge}0.025 mg/L limit. Waste with {ge}260 ppm mercury--For hazardous wastes with mercury contaminant concentrations {ge}260 ppm and RCRA

  18. [Metallic mercury poisoning and neuropsychological effects: a case report].

    Science.gov (United States)

    Cöp, Esra; Cengel Kültür, S Ebru; Erdoğan Bakar, Emel

    2014-01-01

    Mercury is an extremely toxic heavy metal that can devastate central nervous system. We present the case of a 15 year old adolescent with mercury intoxication following 4 days of exposure to elemental mercury at home who was consulted by department of pediatrics with complaints of demonstrated emotional lability, memory impairment, disinhibition, and impulsivity. Olanzapin 2,5 mg/day was initiated. Her neuropsychological performance was evaluated by a neuropsychological test battery at initial examination. Deterioration in neuropsychological functions like interference effect and attention (Stroop Test TBAG form), verbal fluency and switching to other category (Verbal Fluency Test, /(VFT), verbal short term and long term memory and recognition (Auditory Verbal Learning Test, /(AVLT) was detected. In 9 months follow up period her complaints resolved. Initial neuropsychological deficits were also fully recovered at follow up. There was an increase in intelligence scores with increased ability to pay and sustain attention. She had better performance at Stroop Test TBAG form, VFT and AVLT which was similar to her normal peers. In this case report, the clinical aspects of central nervous system involvement in mercury intoxication and protection from potential toxic effects of laboratory materials like mercury at schools were discussed. School administrators should be aware of and parents and students should be given necessary protective information.

  19. Hair mercury levels in Amazonian populations: spatial distribution and trends

    Directory of Open Access Journals (Sweden)

    Barbieri Flavia L

    2009-12-01

    Full Text Available Abstract Background Mercury is present in the Amazonian aquatic environments from both natural and anthropogenic sources. As a consequence, many riverside populations are exposed to methylmercury, a highly toxic organic form of mercury, because of their intense fish consumption. Many studies have analysed this exposure from different approaches since the early nineties. This review aims to systematize the information in spatial distribution, comparing hair mercury levels by studied population and Amazonian river basin, looking for exposure trends. Methods The reviewed papers were selected from scientific databases and online libraries. We included studies with a direct measure of hair mercury concentrations in a sample size larger than 10 people, without considering the objectives, approach of the study or mercury speciation. The results are presented in tables and maps by river basin, displaying hair mercury levels and specifying the studied population and health impact, if any. Results The majority of the studies have been carried out in communities from the central Amazonian regions, particularly on the Tapajós River basin. The results seem quite variable; hair mercury means range from 1.1 to 34.2 μg/g. Most studies did not show any significant difference in hair mercury levels by gender or age. Overall, authors emphasized fish consumption frequency as the main risk factor of exposure. The most studied adverse health effect is by far the neurological performance, especially motricity. However, it is not possible to conclude on the relation between hair mercury levels and health impact in the Amazonian situation because of the relatively small number of studies. Conclusions Hair mercury levels in the Amazonian regions seem to be very heterogenic, depending on several factors. There is no obvious spatial trend and there are many areas that have never been studied. Taking into account the low mercury levels currently handled as acceptable, the

  20. Toxicological Assessments of Rats Exposed Prenatally to Inhaled Vapors of Gasoline and Gasoline-Ethanol Blends

    Science.gov (United States)

    The primary alternative to petroleum-based fuels is ethanol, which is blended with gasoline in the United States at concentrations up to 15% for most automobiles. Efforts to increase the amount of ethanol in gasoline have prompted concerns about the potential toxicity of inhaled ...

  1. Development of a Model for Nerve Agent Inhalation in Conscious Rats

    Science.gov (United States)

    2013-05-23

    Toxicol Mech Meth 14:183–94. Bajgar J. (2004). Organophosphates /nerve agent poisoning : mechanism of action, diagnosis, prophylaxis, and treatment. Adv...See reprint. 15. SUBJECT TERMS Chemical warfare, cholinesterases, inhalation exposure, nerve agents, organophosphates , vapor 16. SECURITY...exposure system for assessing respiratory toxicity of vaporized chemical agents in untreated, non-anesthetized rats. The organophosphate diisopropyl

  2. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    Science.gov (United States)

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-11-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×108 cm-2 s-1 to 1014 cm-2 s-1. The 202Hg(n,γ)203Hg nuclear reaction was used for mercury mass evaluation. Activities of 203Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg2Cl2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps.

  3. Neurodevelopment of Infants in a Mercury Contaminated Crea in Zimbabwe

    Directory of Open Access Journals (Sweden)

    Bose-O’Reilly S.

    2013-04-01

    Full Text Available In Kadoma in Zimbabwe small-scale gold mining is widespread. Mothers and their infants are exposed in the mining communities to the toxic inorganic mercury vapors from processing the ore using elemental mercury. Methyl-mercury is a well known neurotoxin and endangers the regular development of children. This study examined the influence of exposure to elemental mercury for breast fed infants in Kadoma. 121 mother-child pairs were selected, 40 from a non-exposed control area, 81 from the exposed area in Kadoma. Urine, hair and breast milk was analyzed for total mercury. Mainly urine and breast milk levels were significantly higher for the exposed infants. The infants were clinically examined, and their developmental status assessed. In relation to the exposure markers in urine and breast milk several developmental parameters showed statistically significant negative results, such as the capability of infants to sit, crawl or stand at a certain age. These analyzes indicate that a higher body burden with elemental mercury decreases the speed of a regular development of infants.

  4. Health and environmental impact of mercury: Past and present experience

    Science.gov (United States)

    Rivera, A. T. F.; Cortes-Maramba, N. P.; Akagi, H.

    2003-05-01

    Mercury exists in various forms including metallic mercury, inorganie and organic mercury compounds. Research studies show that contamination brought about by natural and man-made activities is clearly a growing problem today. In 1956, the first recognized poisoning outbreaks occurred. Minamata Disease is a disorder of the central nervous system caused by the consumption of fish and shellfish contaminated with methylmercury. Clinical manifestation differs from inorganic mercury poisoning in which the kidneys and the renal system are damaged. The toxidrome consists of sensory disorders in the distal portion of the four extremities, cerebral ataxia, bilateral concentric constriction of the visual field. central disorder of ocular movement, central hearing impairment and disequilibrium. Fetal type Minamata Disease bom of mothers being exposed to methylmercury during pregnancy resulted in conditions similar to those associated with “infantile cerebral palsy" were also documented. Measures to control environmental pollution were implemented such as the environmental restoration project, compensation and relief of victims as part of the health and environmental management undertaken by the government. At present, global research studies are focusing on long-term and low-dose inorganic and methyl mercury exposure; and developmental neurobehavioral toxicity including relevant environmental factors influencing mercury transformations, mass balances and partitioning in ecosystems.

  5. Identification of an archaeal mercury regulon by chromatin immunoprecipitation.

    Science.gov (United States)

    Rudrappa, Deepak; Yao, Andrew I; White, Derrick; Pavlik, Benjamin J; Singh, Raghuveer; Facciotti, Marc T; Blum, Paul

    2015-12-01

    Mercury is a heavy metal and toxic to all forms of life. Metal exposure can invoke a response to improve survival. In archaea, several components of a mercury response system have been identified, but it is not known whether metal transport is a member of this system. To identify such missing components, a peptide-tagged MerR transcription factor was used to localize enriched chromosome regions by chromosome immunoprecipitation combined with DNA sequence analysis. Such regions could serve as secondary regulatory binding sites to control the expression of additional genes associated with mercury detoxification. Among the 31 highly enriched loci, a subset of five was pursued as potential candidates based on their current annotations. Quantitative reverse transcription-PCR analysis of these regions with and without mercury treatment in WT and mutant strains lacking merR indicated significant regulatory responses under these conditions. Of these, a Family 5 extracellular solute-binding protein and the MarR transcription factor shown previously to control responses to oxidation were most strongly affected. Inactivation of the solute-binding protein by gene disruption increased the resistance of mutant cells to mercury challenge. Inductively coupled plasma-MS analysis of the mutant cell line following metal challenge indicated there was less intracellular mercury compared with the isogenic WT strain. Together, these regulated genes comprise new members of the archaeal MerR regulon and reveal a cascade of transcriptional control not previously demonstrated in this model organism.

  6. Impact of inhalation therapy on oral health

    Directory of Open Access Journals (Sweden)

    Navneet Godara

    2011-01-01

    Full Text Available Inhalation therapy has been employed as the mainstay of the treatment in chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD. Beta-2 agonists, anticholinergic bronchodilators, inhaled corticosteroids, and sodium cromoglycate are often used alone or in combination in an inhaled form. Studies have shown that inhaled drugs used in the treatment have some adverse effects on the oral health based on their dosage, frequency, and duration of use. Several oral conditions such as xerostomia, dental caries, candidiasis, ulceration, gingivitis, periodontitis, and taste changes have been associated with inhalation therapy. Since the prevalence of chronic respiratory diseases is rising, it is important to provide optimal oral care to the individuals receiving inhalation therapy. This article will review the influence of inhaled drugs on the oral health of individuals and adequate management and prevention of the same.

  7. Mercury Study Report to Congress

    Science.gov (United States)

    EPA's Report to Congress on Mercury provides an assessment of the magnitude of U.S. mercury emissions by source, the health and environmental implications of those emissions, and the availability and cost of control technologies.

  8. Mercury Emissions: The Global Context

    Science.gov (United States)

    Mercury emissions are a global problem that knows no national or continental boundaries. Mercury that is emitted to the air can travel thousands of miles in the atmosphere before it is eventually deposited back to the earth.

  9. Radiative Forcing associated with Particulate Carbon Emissions resulting from the Use of Mercury Control Technology

    Science.gov (United States)

    Clack, H.; Penner, J. E.; Lin, G.

    2013-12-01

    Mercury is a persistent, toxic metal that bio-accumulates within the food web and causes neurological damage and fetal defects in humans. The U.S. was the first country to regulate the leading anthropogenic source of mercury into the atmosphere: coal combustion for electric power generation. The U.S. EPA's 2005 Clean Air Mercury Rule (CAMR) was replaced and further tightened in 2012 by the Mercury and Air Toxics Standard (MATS), which required existing coal-fired utilities to reduce their mercury emissions by approximately 90% by 2015. Outside the U.S., the Governing Council of the United Nations Environment Programme (UNEP) has passed the legally binding Minamata global mercury treaty that compels its signatory countries to prevent and reduce the emission and release of mercury. The most mature technology for controlling mercury emissions from coal combustion is the injection into the flue gas of powdered activated carbon (PAC) adsorbents having chemically treated surfaces designed to rapidly oxidize and adsorb mercury. However, such PAC is known to have electrical properties that make it difficult to remove from flue gas via electrostatic precipitation, by far the most common particulate control technology used in countries such as the U.S., India, and China which rely heavily on coal for power generation. As a result, PAC used to control mercury emissions can be emitted into the atmosphere, the sub-micron fraction of which may result in unintended radiative forcing similar to black carbon (BC). Here, we estimate the potential increases in secondary BC emissions, those not produced from combustion but arising instead from the use of injected PAC for mercury