An integrated multi-label classifier with chemical-chemical interactions for prediction of chemical toxicity effects.

Science.gov (United States)

Liu, Tao; Chen, Lei; Pan, Xiaoyong

2018-05-31

Chemical toxicity effect is one of the major reasons for declining candidate drugs. Detecting the toxicity effects of all chemicals can accelerate the procedures of drug discovery. However, it is time-consuming and expensive to identify the toxicity effects of a given chemical through traditional experiments. Designing quick, reliable and non-animal-involved computational methods is an alternative way. In this study, a novel integrated multi-label classifier was proposed. First, based on five types of chemical-chemical interactions retrieved from STITCH, each of which is derived from one aspect of chemicals, five individual classifiers were built. Then, several integrated classifiers were built by integrating some or all individual classifiers. By testing the integrated classifiers on a dataset with chemicals and their toxicity effects in Accelrys Toxicity database and non-toxic chemicals with their performance evaluated by jackknife test, an optimal integrated classifier was selected as the proposed classifier, which provided quite high prediction accuracies and wide applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Chemical considerations in severe accident analysis

International Nuclear Information System (INIS)

Malinauskas, A.P.; Kress, T.S.

1988-01-01

The Reactor Safety Study presented the first systematic attempt to include fission product physicochemical effects in the determination of expected consequences of hypothetical nuclear reactor power plant accidents. At the time, however, the data base was sparse, and the treatment of fission product behavior was not entirely consistent or accurate. Considerable research has since been performed to identify and understand chemical phenomena that can occur in the course of a nuclear reactor accident, and how these phenomena affect fission product behavior. In this report, the current status of our understanding of the chemistry of fission products in severe core damage accidents is summarized and contrasted with that of the Reactor Safety Study

Industrial accidents triggered by lightning.

Science.gov (United States)

Renni, Elisabetta; Krausmann, Elisabeth; Cozzani, Valerio

2010-12-15

Natural disasters can cause major accidents in chemical facilities where they can lead to the release of hazardous materials which in turn can result in fires, explosions or toxic dispersion. Lightning strikes are the most frequent cause of major accidents triggered by natural events. In order to contribute towards the development of a quantitative approach for assessing lightning risk at industrial facilities, lightning-triggered accident case histories were retrieved from the major industrial accident databases and analysed to extract information on types of vulnerable equipment, failure dynamics and damage states, as well as on the final consequences of the event. The most vulnerable category of equipment is storage tanks. Lightning damage is incurred by immediate ignition, electrical and electronic systems failure or structural damage with subsequent release. Toxic releases and tank fires tend to be the most common scenarios associated with lightning strikes. Oil, diesel and gasoline are the substances most frequently released during lightning-triggered Natech accidents. Copyright © 2010 Elsevier B.V. All rights reserved.

CADDIS Volume 2. Sources, Stressors and Responses: Unspecified Toxic Chemicals

Science.gov (United States)

Intro to the unspecified toxic chemicals module, when to list toxic chemicals as a candidate cause, ways to measure toxic chemicals, simple and detailed conceptual diagrams for toxic chemicals, toxic chemicals module references and literature reviews.

Managing major chemical accidents in China: Towards effective risk information

International Nuclear Information System (INIS)

He Guizhen; Zhang Lei; Lu Yonglong; Mol, Arthur P.J.

2011-01-01

Chemical industries, from their very inception, have been controversial due to the high risks they impose on safety of human beings and the environment. Recent decades have witnessed increasing impacts of the accelerating expansion of chemical industries and chemical accidents have become a major contributor to environmental and health risks in China. This calls for the establishment of an effective chemical risk management system, which requires reliable, accurate and comprehensive data in the first place. However, the current chemical accident-related data system is highly fragmented and incomplete, as different responsible authorities adopt different data collection standards and procedures for different purposes. In building a more comprehensive, integrated and effective information system, this article: (i) reviews and assesses the existing data sources and data management, (ii) analyzes data on 976 recorded major hazardous chemical accidents in China over the last 40 years, and (iii) identifies the improvements required for developing integrated risk management in China.

TOXRISK, Toxic Gas Release Accident Analysis

International Nuclear Information System (INIS)

Bennett, D.E.; Chanin, D.I.; Shiver, A.W.

1993-01-01

1 - Description of program or function: TOXRISK is an interactive program developed to aid in the evaluation of nuclear power plant control room habitability in the event of a nearby toxic material release. The program uses a model which is consistent with the approach described in the NRC Regulatory Guide 1.78. Release of the gas is treated as an initial puff followed by a continuous plume. The relative proportions of these as well as the plume release rate are supplied by the user. Transport of the gas is modeled as a Gaussian distribution and occurs through the action of a constant velocity, constant direction wind. Great flexibility is afforded the user in specifying the release description, meteorological conditions, relative geometry of the accident and plant, and the plant ventilation system characteristics. Two types of simulation can be performed: multiple case (parametric) studies and probabilistic analyses. Upon execution, TOXRISK presents a menu, and the user chooses between the Data Base Manager, the Multiple Case program, and the Probabilistic Study Program. The Data Base Manager provides a convenient means of storing, retrieving, and modifying blocks of data required by the analysis programs. The Multiple Case program calculates resultant gas concentrations inside the control room and presents a summary of information that describes the event for each set of conditions given. Optimally, a time history profile of inside and outside concentrations can also be produced. The Probabilistic Study program provides a means for estimating the annual probability of operator incapacitation due to toxic gas accidents on surrounding transportation routes and storage sites. 2 - Method of solution: Dispersion or diffusion of the gas during transport is described by modified Pasquill-Gifford dispersion coefficients

DOE contractor's meeting on chemical toxicity

International Nuclear Information System (INIS)

1987-01-01

The Office of Health and Environmental Research (OHER) is required to determine the potential health and environmental effects associated with energy production and use. To ensure appropriate communication among investigators and scientific disciplines that these research studies represent, OHER has sponsored workshops. This document provides a compilation of activities at the Third Annual DOE/OHER Workshop. This year's workshop was broadened to include all OHER activities identified as within the chemical effects area. The workshop consisted of eight sessions entitled Isolation and Detection of Toxic chemicals; Adduct Formation and Repair; Chemical Toxicity (Posters); Metabolism and Genotoxicity; Inhalation Toxicology; Gene Regulation; Metals Toxicity; and Biological Mechanisms. This document contains abstracts of the information presented by session

Toxic chemical hazard classification and risk acceptance guidelines for use in DOE facilities. Revision 2

International Nuclear Information System (INIS)

Craig, D.K.; Davis, J.S.; Prowse, J.; Hoffman, P.W.

1995-01-01

The concentration-limit guidelines presented in this document apply to airborne releases of chemicals evaluated with respect to human health effects for the purposes of hazard classification and categorization, risk assessment and safety analysis. They apply to all DOE facilities and operations involving the use of potentially hazardous chemicals. The guidelines do not address other nonradiological hazards such as fire, pressure releases (including explosions), and chemical reactivity, but the guidelines are applicable to hazardous chemical releases resulting from these events. This report presents the subcommittee's evaluation and recommendations regarding analyses of accidentally released toxic chemicals. The premise upon which these recommendations are based is that the mechanism of action of toxic chemicals is fundamentally different from that associated with radionuclides, with the exception of carcinogens. The recommendations reported herein are restricted to the airborne pathway because in an accident scenario this typically represents the most immediately significant route of public exposure. However, the subcommittee recognizes that exposure to chemicals through other pathways, in particular waterborne, can have significant impacts on human health and the environment. Although there are a number of chemicals for which absorption through the skin can contribute measurably to the total dose in chronic (e.g., occupational) exposure situations, this pathway has not been considered for the acute exposure scenarios considered in this report. Later studies. will address these issues if it appears desirable

The unique field experiments on the assessment of accident consequences at industrial enterprises of gas-chemical complexes

International Nuclear Information System (INIS)

Belov, N.S.; Trebin, I.S.; Sorokovikova, O.

1998-01-01

Sour natural gas fields are the unique raw material base for setting up such large enterprises as gas chemical complexes. The presence of high toxic H 2 S in natural gas results in widening a range of dangerous and harmful factors for biosphere. Emission of such gases into atmosphere during accidents at gas wells and gas pipelines is of especial danger for environment and first of all for people. Development of mathematical forecast models for assessment of accidents progression and consequences is one of the main elements of works on safety analysis and risk assessment. The critical step in development of such models is their validation using the experimental material. Full-scale experiments have been conducted by the All-Union Scientific-Research institute of Natural Gases and Gas Technology (VNIIGAZ) for grounding of sizes of hazard zones in case of the severe accidents with the gas pipelines. The source of emergency gas release was the working gas pipelines with 100 mm dia. And 110 km length. This pipeline was used for transportation of natural gas with significant amount of hydrogen sulphide. During these experiments significant quantities of the gas including H 2 S were released into the atmosphere and then concentrations of gas and H 2 S were measured in the accident region. The results of these experiments are used for validation of atmospheric dispersion models including the new Lagrangian trace stochastic model that takes into account a wide range of meteorological factors. This model was developed as a part of computer system for decision-making support in case of accident release of toxic gases into atmosphere at the enterprises of Russian gas industry. (authors)

Toxic Release Inventory Chemicals by Groupings

Data.gov (United States)

U.S. Environmental Protection Agency — The Toxics Release Inventory (TRI) makes available information for more than 600 toxic chemicals that are being used, manufactured, treated, transported, or released...

Toxicity evaluation and prediction of toxic chemicals on activated sludge system.

Science.gov (United States)

Cai, Bijing; Xie, Li; Yang, Dianhai; Arcangeli, Jean-Pierre

2010-05-15

The gaps of data for evaluating toxicity of new or overloaded organic chemicals on activated sludge system resulted in the requirements for methodology of toxicity estimation. In this study, 24 aromatic chemicals typically existed in the industrial wastewater were selected and classified into three groups of benzenes, phenols and anilines. Their toxicity on activated sludge was then investigated. Two indexes of IC(50-M) and IC(50-S) were determined respectively from the respiration rates of activated sludge with different toxicant concentration at mid-term (24h) and short-term (30min) time intervals. Experimental results showed that the group of benzenes was the most toxic, followed by the groups of phenols and anilines. The values of IC(50-M) of the tested chemicals were higher than those of IC(50-S). In addition, quantitative structure-activity relationships (QSARs) models developed from IC(50-M) were more stable and accurate than those of IC(50-S). The multiple linear models based on molecular descriptors and K(ow) presented better reliability than single linear models based on K(ow). Among these molecular descriptors, E(lumo) was the most important impact factor for evaluation of mid-term toxicity. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Low-level toxicity of chemicals: No acceptable levels?

Directory of Open Access Journals (Sweden)

Bruce P Lanphear

2017-12-01

Full Text Available Over the past 3 decades, in a series of studies on some of the most extensively studied toxic chemicals and pollutants, scientists have found that the amount of toxic chemical linked with the development of a disease or death-which is central to determining "safe" or "hazardous" levels-is proportionately greater at the lowest dose or levels of exposure. These results, which are contrary to the way the United States Environmental Protection Agency (EPA and other regulatory agencies assess the risk of chemicals, indicate that we have underestimated the impact of toxic chemicals on death and disease. If widely disseminated chemicals and pollutants-like radon, lead, airborne particles, asbestos, tobacco, and benzene-do not exhibit a threshold and are proportionately more toxic at the lowest levels of exposure, we will need to achieve near-zero exposures to protect public health.

Yellow phosphorus process to convert toxic chemicals to non-toxic products

Science.gov (United States)

Chang, S.G.

1994-07-26

The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

THE ATMOSPHERE PROTECTION FROM AN ACCIDENT WITH HAZARDOUS CHEMICAL CARGO

Directory of Open Access Journals (Sweden)

V. M. Lysniak

2009-09-01

Full Text Available The 3D CFD model to simulate the pollutant transfer and the process of neutralization of toxic gas after accidents was developed. The model is based on the transport gradient model. The results of numerical experiments are presented.

Case examples of chemical plant accidents. What we learn from them?

International Nuclear Information System (INIS)

Nakamura, Masayoshi

2009-01-01

Lessons learned from the JCO Nuclear Criticality Accident of 30 September 1999 in a uranium conversion test plant in Tokai-mura, Japan, are reviewed by referring some pertinent matters from the official report of this accident to remind of the universal characteristics among possible accidents of chemical plants. The paper discusses the responsibility of the establishment or institution to the demand alternation or request change from the client, how to respond to the proposal arising from the factory floor, and the safety control system of every-day maintenance of the factory which are important to prevent accidents in chemical plants. After explaining a background leading to the JCO accident, the author summarizes the lessons as follows: (1) changeable control system, (2) perfect provision of the manual considering the actual condition, and (3) clarification of the roles each played by the managers and the workers are most necessary and important. (S. Ohno)

Runaway chemical reaction exposes community to highly toxic chemicals

International Nuclear Information System (INIS)

Kaszniak, Mark; Vorderbrueggen, John

2008-01-01

The U.S. Chemical Safety and Hazard Investigation Board (CSB) conducted a comprehensive investigation of a runaway chemical reaction at MFG Chemical (MFG) in Dalton, Georgia on April 12, 2004 that resulted in the uncontrolled release of a large quantity of highly toxic and flammable allyl alcohol and allyl chloride into the community. Five people were hospitalized and 154 people required decontamination and treatment for exposure to the chemicals. This included police officers attempting to evacuate the community and ambulance personnel who responded to 911 calls from residents exposed to the chemicals. This paper presents the findings of the CSB report (U.S. Chemical Safety and Hazard Investigation Board (CSB), Investigation Report: Toxic Chemical Vapor Cloud Release, Report No. 2004-09-I-GA, Washington DC, April 2006) including a discussion on tolling practices; scale-up of batch reaction processes; Process Safety Management (PSM) and Risk Management Plan (RMP) implementation; emergency planning by the company, county and the city; and emergency response and mitigation actions taken during the incident. The reactive chemical testing and atmospheric dispersion modeling conducted by CSB after the incident and recommendations adopted by the Board are also discussed

Managing major chemical accidents in China: Towards effective risk information

NARCIS (Netherlands)

He, G.; Zhang, L.; Lu, Y.; Mol, A.P.J.

2011-01-01

Chemical industries, from their very inception, have been controversial due to the high risks they impose on safety of human beings and the environment. Recent decades have witnessed increasing impacts of the accelerating expansion of chemical industries and chemical accidents have become a major

Chemical toxicity approach for emergency response

International Nuclear Information System (INIS)

Bauer, T.

2009-01-01

In the event of an airborne release of chemical agent or toxic industrial chemical by accidental or intentional means, emergency responders must have a reasonable estimate of the location and size of the resulting hazard area. Emergency responders are responsible for warning persons downwind of the hazard to evacuate or shelter-in-place and must know where to look for casualties after the hazard has passed or dissipated. Given the same source characterization, modern hazard assessment models provide comparable concentration versus location and time estimates. Even urban hazard assessment models often provide similar predictions. There is a major shortcoming, though, in applying model output to estimating human toxicity effects. There exist a variety of toxicity values for non-lethal effects ranging from short-term to occupational to lifetime exposures. For health and safety purposes, these estimates are all safe-sided in converting animal data to human effects and in addressing the most sensitive subset of the population. In addition, these values are usually based on an assumed 1 hour exposure duration at constant concentration and do not reflect either a passing clouds concentration profile or duration. Emergency responders need expected value toxicity parameters rather than the existing safe-sided ones. This presentation will specify the types of toxicity values needed to provide appropriate chemical hazard estimates to emergency responders and will demonstrate how dramatically their use changes the hazard area.(author)

The Industrial Toxics Project: Targeting chemicals for environmental results

International Nuclear Information System (INIS)

Burch, W.M.

1991-01-01

In September, 1990, the Administrator of the US Environmental Protection Agency committed the Agency to a program of targeting chemicals for multi-media risk reduction activities through pollution prevention. The Industrial Toxics Project will place emphasis on obtaining voluntary commitments from industry to reduce releases of toxic chemicals to the air, water, and land with a goal of reducing releases nationwide by 33% by 1992 and 50% by 1995. An initial list of 18 chemicals have been selected based on recommendations from each Agency program. The chemicals selected are subject to reporting under the Toxic Chemical Release Inventory Program which will provide the basis for tracking progress. The chemicals are characterized by high production volume, toxicity and releases and present the potential for significant risk reduction through pollution prevention. This presentation will discuss the focus and direction of this new initiative

Comparative toxicity of chemicals to earthworms

Energy Technology Data Exchange (ETDEWEB)

Callahan, C.A.; Shirazi, M.A. (Environmental Protection Agency, Corvallis, OR (United States)); Neuhauser, E.F. (Niagara Mohawk Power Corp., Syracuse, NY (United States))

1994-02-01

The concentration-response (mortality) relationships of four species of earthworms, Eisenia fetida (Savigny), Allolobophora tuberculata (Eisen), Eudrilus eugeniae (Kinberg), and Perionyx excavatus (Perrier) are summarized for 62 chemicals and two test protocols. A Weibull function is used to summarize these data for each chemical in terms of sensitivity and toxicity, in addition to the LC50. The estimation of the Weibull parameters a and k summarize the entire concentration-response relationship. This technique should be applicable to a variety of testing protocols with different species whenever the goal is summarizing the shape of the concentration-response curves to fully evaluate chemical impact on organisms. In some cases for these data four orders of magnitude separate LC50s of the soil test and the contact test for the same chemical and species. All four species appear to be similar in range of toxicity and tolerance to these chemicals, suggesting that Eisenia fetida and may be representative of these four species and these chemicals.

CADDIS Volume 2. Sources, Stressors and Responses: Unspecified Toxic Chemicals - Detailed Conceptual Diagram

Science.gov (United States)

Intro to the unspecified toxic chemicals module, when to list toxic chemicals as a candidate cause, ways to measure toxic chemicals, simple and detailed conceptual diagrams for toxic chemicals, toxic chemicals module references and literature reviews.

CADDIS Volume 2. Sources, Stressors and Responses: Unspecified Toxic Chemicals - Simple Conceptual Diagram

Science.gov (United States)

Intro to the unspecified toxic chemicals module, when to list toxic chemicals as a candidate cause, ways to measure toxic chemicals, simple and detailed conceptual diagrams for toxic chemicals, toxic chemicals module references and literature reviews.

Toxic chemicals: risk prevention through use reduction

National Research Council Canada - National Science Library

Higgins, Thomas E; Sachdev, Jayanti A; Engleman, Stephen A

2011-01-01

... on the actual toxicity of chemicals currently in use, discusses variables that contribute to the relative toxicity of a substance, compares alternate emphases in existing programs for reducing environmental...

Possibility of the development of a Serbian protection system against chemical accidents

Directory of Open Access Journals (Sweden)

Dejan R. Inđić

2012-10-01

Full Text Available The paper presents a draft of a system model for responding in case of chemical accidents in accordance with the current legislation regarding the environment protection, the structure and elements of the existing response system in case of chemical accidents, other works dealing with the issue as well as the prospects planned by those responsible for the environmental protection. The paper discuss the possibilities of different institutions and agencies of the Republic of Serbia to engage in specialized methods of cooperation and protection against chemical hazards in accordance with Article X of the Convention on the Prohibition of Chemical Weapons.

Lessons learned from major accidents relating to ageing of chemical plants

OpenAIRE

GYENES ZSUZSANNA; WOOD Maureen

2016-01-01

Major industrial accidents that occurred in the past and even recently, such as the Flixborough, UK in 1974, the ConocoPhillips, UK in 2001 and the Chevron, US in 2012 show that ageing is still a disturbing phenomenon present in chemical process industries. Further to these cases, it is estimated that 30 % of the major accidents reported in the eMARS accident database run by the Major Accident Hazards Bureau of the European Commission are connected to at least one ageing phenomenon. It is som...

Chemical and nuclear emergencies: Interchanging lessons learned from planning and accident experience

International Nuclear Information System (INIS)

Adler, V.; Sorensen, J.H.; Rogers, G.O.

1989-01-01

Because the goal of emergency preparedness for both chemical and nuclear hazards is to reduce human exposure to hazardous materials, this paper examines the interchange of lessons learned from emergency planning and accident experience in both industries. While the concerns are slightly different, sufficient similarity is found for each to draw implications from the others experience. Principally the chemical industry can learn from the dominant planning experience associated with nuclear power plants, while the nuclear industry can chiefly learn from the chemical industry's accident experience. 23 refs

2008 Toxic Chemical Release Inventory 2008 Toxic Chemical Release Inventory Community Right-to-Know Act of 1986, Title III, Section 313

Energy Technology Data Exchange (ETDEWEB)

Ecology and Air Quality Group

2009-10-01

For reporting year 2008, Los Alamos National Laboratory (LANL) submitted a Form R report for lead as required under the Emergency Planning and Community Right-to- Know Act (EPCRA) Section 313. No other EPCRA Section 313 chemicals were used in 2008 above the reportable thresholds. This document was prepared to provide a description of the evaluation of EPCRA Section 313 chemical use and threshold determinations for LANL for calendar year 2008, as well as to provide background information about data included on the Form R reports. Section 313 of EPCRA specifically requires facilities to submit a Toxic Chemical Release Inventory Report (Form R) to the U.S. Environmental Protection Agency (EPA) and state agencies if the owners and operators manufacture, process, or otherwise use any of the listed toxic chemicals above listed threshold quantities. EPA compiles this data in the Toxic Release Inventory database. Form R reports for each chemical over threshold quantities must be submitted on or before July 1 each year and must cover activities that occurred at the facility during the previous year. In 1999, EPA promulgated a final rule on persistent bioaccumulative toxics (PBTs). This rule added several chemicals to the EPCRA Section 313 list of toxic chemicals and established lower reporting thresholds for these and other PBT chemicals that were already reportable. These lower thresholds became applicable in reporting year 2000. In 2001, EPA expanded the PBT rule to include a lower reporting threshold for lead and lead compounds. Facilities that manufacture, process, or otherwise use more than 100 lb of lead or lead compounds must submit a Form R.

Enforcement Alert: EPA Enforcement Efforts Focus on Prevention of Chemical Accidents

Science.gov (United States)

This Alert is intended to inform the industry that companies must take responsibility to prevent accidental releases of dangerous chemicals like anhydrous ammonia through compliance with CAA’s Chemical Accident Prevention Program.

Chemical factors affecting fission product transport in severe LMFBR accidents

International Nuclear Information System (INIS)

Wichner, R.P.; Jolley, R.L.; Gat, U.; Rodgers, B.R.

1984-10-01

This study was performed as a part of a larger evaluation effort on LMFBR accident, source-term estimation. Purpose was to provide basic chemical information regarding fission product, sodium coolant, and structural material interactions required to perform estimation of fission product transport under LMFBR accident conditions. Emphasis was placed on conditions within the reactor vessel; containment vessel conditions are discussed only briefly

Comparative toxicity of ten organic chemicals to four earthworm species

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, E.F.; Durkin, P.R.; Malecki, M.R.; Anatra, M.

1986-01-01

Ten organic chemicals were tested for toxicity to four earthworm species: Allolobophora tuberculata, Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, using the European Economic Community's (EEC) earthworm artificial soil and contact testing procedure. The phenols were the most toxic chemicals tested, followed by the amine, substituted benzenes, halogenated aliphatic hydrocarbon, polycyclic aromatic hydrocarbon and phthalate as the least toxic chemical tested. Correlations among species within each type of test for a given chemical were extremely high, suggesting that the selection of earthworm test species does not markedly affect the assessment of a chemical's toxicity. The correlation between the two tests was low for all test species. The contact test LC50 for a given chemical cannot be directly correlated to an artificial soil test LC50 for the same earthworm species.

Onshore preparedness for hazardous chemical marine vessel accidents: A case study

Directory of Open Access Journals (Sweden)

Faisel T. Illiyas

2016-09-01

Full Text Available Hazardous and noxious substances (HNS are widely transported in marine vessels to reach every part of the world. Bulk transportation of hazardous chemicals is carried out in tank container–carrying cargo ships or in designed vessels. Ensuring the safety of HNS containers during maritime transportation is critically important as the accidental release of any substance may be lethal to the on-board crew and marine environment. A general assumption in maritime accidents in open ocean is that it will not create any danger to the coastal population. The case study discussed in this article throws light on the dangers latent in maritime HNS accidents. An accident involving an HNS-carrying marine vessel in the Arabian Sea near the coast of Yemen became a safety issue to the coastal people of Kasargod District of Kerala, India. The ship carried more than 4000 containers, which were lost to the sea in the accident. Six HNS tank containers were carried by the waves and shored at the populated coast of Kasargod, more than 650 nautical miles east from the accident spot. The unanticipated sighting of tank containers in the coast and the response of the administration to the incident, the hurdles faced by the district administration in handling the case, the need for engaging national agencies and lessons learned from the incident are discussed in the article. This case study has proven that accidents in the open ocean have the potential to put the coastal areas at risk if the on-board cargo contains hazardous chemicals. Littoral nations, especially those close to the international waterlines, must include hazardous chemical spills to their oil spill contingency plans.

DOE contractor's meeting on chemical toxicity

Energy Technology Data Exchange (ETDEWEB)

1987-01-01

The Office of Health and Environmental Research (OHER) is required to determine the potential health and environmental effects associated with energy production and use. To ensure appropriate communication among investigators and scientific disciplines that these research studies represent, OHER has sponsored workshops. This document provides a compilation of activities at the Third Annual DOE/OHER Workshop. This year's workshop was broadened to include all OHER activities identified as within the chemical effects area. The workshop consisted of eight sessions entitled Isolation and Detection of Toxic chemicals; Adduct Formation and Repair; Chemical Toxicity (Posters); Metabolism and Genotoxicity; Inhalation Toxicology; Gene Regulation; Metals Toxicity; and Biological Mechanisms. This document contains abstracts of the information presented by session.

Transformation of highly toxic chemicals factory for Fuqing nuclear power plant

International Nuclear Information System (INIS)

Wang Hongkai; Gao Yuan; Li Hua

2014-01-01

For the iodine adsorption tests of current M310 nuclear power plant, dimethyl sulfate is one of highly toxic chemical of national strict standard management, and the nation make strict control over toxic chemicals procurement, transportation, storage, management requirements. Since the appropriate toxic chemicals storage place was not considered in the design of M310 nuclear power plant, Fuqing nuclear power sites for storage of dimethyl sulfate implement technical transformation to meet and regulate the storage requirements for highly toxic chemical. This will lay the foundation for carrying out smoothly the relevant tests of nuclear power plant, and provide the reference for the use and construction of toxic chemicals reactor in the same type nuclear power plant. (authors)

Novel view on predicting acute toxicity: Decomposing toxicity data in species vulnerability and chemical potency.

NARCIS (Netherlands)

Jager, D.T.; Posthuma, L.; Zwart, D.D.; van de Meent, D.

2007-01-01

Chemical risk assessment usually applies empirical methods to predict toxicant effects on different species. We propose a more mechanism-oriented approach, and introduce a method to decompose toxicity data in a contribution from the chemical (potency) and from the exposed species (vulnerability). We

Comparison of the radiological and chemical toxicity of lead

Energy Technology Data Exchange (ETDEWEB)

Beitel, G.A.; Mott, S.

1995-03-01

This report estimates the worst-case radiological dose to an individual from ingested lead containing picocurie levels of radionuclides and then compares the calculated radiological health effects to the chemical toxic effects from that same lead. This comparison provides an estimate of the consequences of inadvertently recycling, in the commercial market, lead containing nominally undetectable concentrations of radionuclides. Quantitative expressions for the radiological and chemical toxicities of lead are based on concentrations of lead in the blood stream. The result shows that the chemical toxicity of lead is a greater health hazard, by orders of magnitude, than any probable companion radiation dose.

Comparison of the radiological and chemical toxicity of lead

International Nuclear Information System (INIS)

Beitel, G.A.; Mott, S.

1995-03-01

This report estimates the worst-case radiological dose to an individual from ingested lead containing picocurie levels of radionuclides and then compares the calculated radiological health effects to the chemical toxic effects from that same lead. This comparison provides an estimate of the consequences of inadvertently recycling, in the commercial market, lead containing nominally undetectable concentrations of radionuclides. Quantitative expressions for the radiological and chemical toxicities of lead are based on concentrations of lead in the blood stream. The result shows that the chemical toxicity of lead is a greater health hazard, by orders of magnitude, than any probable companion radiation dose

In silico toxicology: computational methods for the prediction of chemical toxicity

KAUST Repository

Raies, Arwa B.; Bajic, Vladimir B.

2016-01-01

Determining the toxicity of chemicals is necessary to identify their harmful effects on humans, animals, plants, or the environment. It is also one of the main steps in drug design. Animal models have been used for a long time for toxicity testing. However, in vivo animal tests are constrained by time, ethical considerations, and financial burden. Therefore, computational methods for estimating the toxicity of chemicals are considered useful. In silico toxicology is one type of toxicity assessment that uses computational methods to analyze, simulate, visualize, or predict the toxicity of chemicals. In silico toxicology aims to complement existing toxicity tests to predict toxicity, prioritize chemicals, guide toxicity tests, and minimize late-stage failures in drugs design. There are various methods for generating models to predict toxicity endpoints. We provide a comprehensive overview, explain, and compare the strengths and weaknesses of the existing modeling methods and algorithms for toxicity prediction with a particular (but not exclusive) emphasis on computational tools that can implement these methods and refer to expert systems that deploy the prediction models. Finally, we briefly review a number of new research directions in in silico toxicology and provide recommendations for designing in silico models.

In silico toxicology: computational methods for the prediction of chemical toxicity

KAUST Repository

Raies, Arwa B.

2016-01-06

Determining the toxicity of chemicals is necessary to identify their harmful effects on humans, animals, plants, or the environment. It is also one of the main steps in drug design. Animal models have been used for a long time for toxicity testing. However, in vivo animal tests are constrained by time, ethical considerations, and financial burden. Therefore, computational methods for estimating the toxicity of chemicals are considered useful. In silico toxicology is one type of toxicity assessment that uses computational methods to analyze, simulate, visualize, or predict the toxicity of chemicals. In silico toxicology aims to complement existing toxicity tests to predict toxicity, prioritize chemicals, guide toxicity tests, and minimize late-stage failures in drugs design. There are various methods for generating models to predict toxicity endpoints. We provide a comprehensive overview, explain, and compare the strengths and weaknesses of the existing modeling methods and algorithms for toxicity prediction with a particular (but not exclusive) emphasis on computational tools that can implement these methods and refer to expert systems that deploy the prediction models. Finally, we briefly review a number of new research directions in in silico toxicology and provide recommendations for designing in silico models.

SCREENING FOR TOXIC INDUSTRIAL CHEMICALS USING SEMIPERMEABLE MEMBRANE DEVICES WITH RAPID TOXICITY ASSAYS

Science.gov (United States)

A time-integrated sampling device interfaced with two toxicity-based assays is reported for monitoring volatile toxic industrial chemicals (TICs). Semipermeable membrane devices (SPMDs) using dimethylsulfoxide (DMSO) as the fill solvent accumulated each of 17 TICs from the vapor...

Toxicity studies of drugs and chemicals in animals: An overview

Directory of Open Access Journals (Sweden)

S. Saganuwan

2017-12-01

Full Text Available Toxicity study is the investigation of either short or long-term toxic effects of a drug or chemical on animals. The toxicity is dose-dependent as asserted by Paracelsus over 500 years ago. However, short-term toxic effect is determined using median lethal dose (LD50 first introduced by Trevan in 1927 and revised many times. Presently there is a growing preponderance of rejection of scientific papers on acute toxicity study, simply because of the belief that in the current hazard and safety as-sessment of drugs and chemicals, LD50 values are no longer used. In view of this, literature search was carried out with a view to investigating the relevance of LD50 in development and assessment of drugs and chemicals. The findings revealed that in the past, many animals had been used for LD50 determination. OECD has reduced the number of test animals to 5–15 and presently it is further re-duced to 2–6. Acute toxicity study is being carried out in medicinal plants research and in the study of patent medicine. Although the application of LD50 has been drastically reduced, it is still applied and accepted in some parts of the world. Moreover, animals on which LD50 tests are conducted, should be allowed to die to see the end effect of the test drug or chemical because euthanisia of test animals may mask some toxicity signs of the test agents. Therefore, toxicity study of drugs and chemicals is a sci-entific process necessary for discovery and development of drugs as well as identification of potential toxicants.

Destruction of highly toxic chemical materials by using the energy of underground thermonuclear explosion

International Nuclear Information System (INIS)

Trutnev, Y.

1991-01-01

One of the main problems of modern technogenic civilisation is the evergrowing ecological crisis caused by the growth of industrial wastes harmful for biosphere. Among them the radioactive wastes of atomic energetics, worked out nuclear energy facilities and toxic wastes from various chemical plants begin to play a specific role. Traditional technologies of destruction and disposal of these wastes demand great investments up to many billions of dollars, enormous maintenance expenditures, occupation of substantial territories by new productions and security zones as well as many qualified specialists. On the other hand potential accidents during the conventional processes of waste reprocessing are fraught with the possibility of large ecological disasters, that are the reason of strong oppositions of population and 'green movement' to the foundation of such installations. So, rather progressive seem to be the technologies based on the utilisation of underground nuclear explosion energy for annihilations and disposal of high-level wastes of atomic energetics and nuclear facilities as well as for thermal decomposition of chemically toxic substances at extremely high temperatures. These technologies will be rather cheap, they will allow to process big amounts of materials in ecologically safe form far from the populated regions and will need a commercially beneficial if used for international purposes. The application of these technologies may be of great significance for realisation of disarmament process- destruction of chemical weapons and in future the nuclear warheads and some production components. (au)

Comprehensive assessment of toxic chemical pollutants at Trombay region

International Nuclear Information System (INIS)

Sahu, S.K.; Saradhi, I.V.; Raghunath, R.; Pandit, G.G.; Puranik, V.D.

2006-04-01

Anthropogenic activities like industrial production and transportation, a wide range of chemical pollutants such as trace and toxic metals, pesticides, polycyclic aromatic hydrocarbons etc. eventually found their way into various environmental compartments. These pollutants get distributed among soil, water bodies, air and if left unattended can cause serious health risk to all exposed ecosystem components including human beings. These compounds may produce immediate toxicity to ecosystems or exhibit long term effects such as mutagenicity, carcinogenicity or biomagnify (concentrations of pollutant increase per unit body weight) in higher trophic organism of the food chain. Thus regular monitoring of these toxic chemicals in all the environmental matrices is unquestionably essential for reclaiming our natural resources. This report describes some of the activities of Environmental Assessment Division which are having direct relevance to the public health and regulatory bodies. Extensive studies were carried out in our laboratories for the Trombay site, over the years; on the organic as well as inorganic pollution in the environment to understand inter compartmental behaviour of these chemical pollutants. In this report attempt has been made to compare the data on various toxic chemical pollutants that are being monitored regularly at Trombay site and their levels are compared with existing regulations. For monitoring, methodologies have been standardized for characterization of toxic chemical pollutants using different analytical techniques. Regular sample collection from different environmental matrices has been done. Sample analysis has been carried out using different analytical instruments such as high performance liquid chromatograph, ion chromatograph, gas chromatograph, atomic absorption spectrophotometer, and differential pulse anodic stripping voltammetry. Major portion of the study covers Air quality monitoring of toxic chemical pollutants, as the other

[Preparation of the database and the homepage on chemical accidents relating to health hazard].

Science.gov (United States)

Yamamoto, M; Morita, M; Kaminuma, T

1998-01-01

We collected the data on accidents due to chemicals occurred in Japan, and prepared the database. We also set up the World Wide Web homepage containing the explanation on accidents due to chemicals and the retrieval page for the database. We designed the retrieval page so that users can search the data from keywords such as chemicals (e.g. chlorine gas, hydrogen sulfide, pesticides), places (e.g. home, factory, vehicles, tank), causes (e.g. reaction, leakage, exhaust gas) and others (e.g. cleaning, painting, transportation).

Domino effect in chemical accidents: main features and accident sequences

OpenAIRE

Casal Fàbrega, Joaquim; Darbra Roman, Rosa Maria

2010-01-01

The main features of domino accidents in process/storage plants and in the transportation of hazardous materials were studied through an analysis of 225 accidents involving this effect. Data on these accidents, which occurred after 1961, were taken from several sources. Aspects analyzed included the accident scenario, the type of accident, the materials involved, the causes and consequences and the most common accident sequences. The analysis showed that the most frequent causes a...

Metal-organic frameworks for the removal of toxic industrial chemicals and chemical warfare agents.

Science.gov (United States)

Bobbitt, N Scott; Mendonca, Matthew L; Howarth, Ashlee J; Islamoglu, Timur; Hupp, Joseph T; Farha, Omar K; Snurr, Randall Q

2017-06-06

Owing to the vast diversity of linkers, nodes, and topologies, metal-organic frameworks can be tailored for specific tasks, such as chemical separations or catalysis. Accordingly, these materials have attracted significant interest for capture and/or detoxification of toxic industrial chemicals and chemical warfare agents. In this paper, we review recent experimental and computational work pertaining to the capture of several industrially-relevant toxic chemicals, including NH 3 , SO 2 , NO 2 , H 2 S, and some volatile organic compounds, with particular emphasis on the challenging issue of designing materials that selectively adsorb these chemicals in the presence of water. We also examine recent research on the capture and catalytic degradation of chemical warfare agents such as sarin and sulfur mustard using metal-organic frameworks.

Materials Safety Data Sheets: the basis for control of toxic chemicals

Energy Technology Data Exchange (ETDEWEB)

Ketchen, E.E.; Porter, W.E.

1979-09-01

The Material Safety Data Sheets contained in this volume are the basis for the Toxic Chemical Control Program developed by the Industrial Hygiene Department, Health Division, ORNL. The three volumes are the update and expansion of ORNL/TM-5721 and ORNL/TM-5722 Material Safety Data Sheets: The Basis for Control of Toxic Chemicals, Volume I and Volume II. As such, they are a valuable adjunct to the data cards issued with specific chemicals. The chemicals are identified by name, stores catalog number where appropriate, and sequence numbers from the NIOSH Registry of Toxic Effects of Chemical Substances, 1977 Edition, if available. The data sheets were developed and compiled to aid in apprising the employees of hazards peculiar to the handling and/or use of specific toxic chemicals. Space limitation necessitate the use of descriptive medical terms and toxicological abbreviations. A glossary and an abbreviation list were developed to define some of those sometimes unfamiliar terms and abbreviations. The page numbers are keyed to the catalog number in the chemical stores at ORNL.

Meta-analysis of toxicity and teratogenicity of 133 chemicals from zebrafish developmental toxicity studies

Science.gov (United States)

Zebrafish developmental toxicity testing is an emerging field, which faces considerable challenges regarding data meta-analysis and the establishment of standardized test protocols. Here, we present an initial correlation study on toxicity of 133 chemicals based on data in the li...

76 FR 7841 - Agency Information Collection Activities; Proposed Collections; Toxic Chemical Release Reporting...

Science.gov (United States)

2011-02-11

... agencies, and others to promote reductions in toxic chemical releases. Industrial facilities use the TRI... Activities; Proposed Collections; Toxic Chemical Release Reporting; Request for Comments on Proposed Renewal... the individual listed in the preceding FOR FURTHER INFORMATION CONTACT section. Title: Toxic Chemical...

Electron Beam Treatment of Toxic Chemicals

International Nuclear Information System (INIS)

Jung, In Ha; Lee, Myun Joo; Lee, Oh Mi; Kim, Tae Hoon

2011-01-01

Polychlorinated biphenyls (PCBs) were commercially produced from 1920s as complex mixtures containing multiple isomers for a variety of applications. They are very toxic, chemically stable and resist microbial, photochemical, chemical, and thermal degradation. The public, legal, and scientific concerns about PCBs arose from research indicating they were environmental contaminants that had a potential to adversely impact the environment, and, therefore, were undesirable as commercial products. Eventually, most producers reduced or stopped production of PCBs in the 1970s. Stockholm convention on POPs (Persistent Organic Pollutants), which was effective on May 2004 and 151 nations including Korea were joined on June 2005, asked to dispose of PCBs by 2028 with environmental friendly methods. Korean government also has declared to perform by 2015. According to the Environmental law of Korea, over 2 ppm of PCBs has to be decomposed by legal methods of incineration and thermal destruction. But those are inapplicable owing to the environmental groups. KAERI(Korea Atomic Energy Research Institute) has recently developed a remarkable technology for radiation treatment of toxic chemicals including chlorides using an electron beam accelerator

Domino effect in chemical accidents: main features and accident sequences.

Science.gov (United States)

Darbra, R M; Palacios, Adriana; Casal, Joaquim

2010-11-15

The main features of domino accidents in process/storage plants and in the transportation of hazardous materials were studied through an analysis of 225 accidents involving this effect. Data on these accidents, which occurred after 1961, were taken from several sources. Aspects analyzed included the accident scenario, the type of accident, the materials involved, the causes and consequences and the most common accident sequences. The analysis showed that the most frequent causes are external events (31%) and mechanical failure (29%). Storage areas (35%) and process plants (28%) are by far the most common settings for domino accidents. Eighty-nine per cent of the accidents involved flammable materials, the most frequent of which was LPG. The domino effect sequences were analyzed using relative probability event trees. The most frequent sequences were explosion→fire (27.6%), fire→explosion (27.5%) and fire→fire (17.8%). Copyright © 2010 Elsevier B.V. All rights reserved.

Analysis of Waste Leak and Toxic Chemical Release Accidents from Waste Feed Delivery (WFD) Diluent System

Energy Technology Data Exchange (ETDEWEB)

WILLIAMS, J.C.

2000-09-15

Radiological and toxicological consequences are calculated for 4 postulated accidents involving the Waste Feed Delivery (WFD) diluent addition systems. Consequences for the onsite and offsite receptor are calculated. This analysis contains technical information used to determine the accident consequences for the River Protection Project (RPP) Final Safety Analysis Report (FSAR).

Analysis of Waste Leak and Toxic Chemical Release Accidents from Waste Feed Delivery (WFD) Diluent System

International Nuclear Information System (INIS)

WILLIAMS, J.C.

2000-01-01

Radiological and toxicological consequences are calculated for 4 postulated accidents involving the Waste Feed Delivery (WFD) diluent addition systems. Consequences for the onsite and offsite receptor are calculated. This analysis contains technical information used to determine the accident consequences for the River Protection Project (RPP) Final Safety Analysis Report (FSAR)

Toxicity assessment of unintentional exposure to multiple chemicals

International Nuclear Information System (INIS)

Mumtaz, M.M.; Ruiz, P.; De Rosa, C.T.

2007-01-01

Typically exposure to environmental chemicals is unintentional, and often the exposure is to chemical mixtures, either simultaneously or sequentially. When exposure occurs, in public health practice, it is prudent to ascertain if thresholds for harmful health effects are exceeded, whether by individual chemicals or by chemicals in combination. Three alternative approaches are available for assessing the toxicity of chemical mixtures. Each approach, however, has shortcomings. As the procedures of each approach are described in this paper, at various steps research needs are identified. Recently, reliance has increased on computational toxicology methods for predicting toxicological effects when data are limited. Advances in molecular biology, identification of biomarkers, and availability of accurate and sensitive methods allow us to more precisely define the relationships between multiple chemical exposures and health effects, both qualitatively and quantitatively. Key research needs are best fulfilled through collaborative research. It is through such collaborations that resources are most effectively leveraged to further develop and apply toxicity assessment methods that advance public health practices in vulnerable communities

An novel identification method of the environmental risk sources for surface water pollution accidents in chemical industrial parks.

Science.gov (United States)

Peng, Jianfeng; Song, Yonghui; Yuan, Peng; Xiao, Shuhu; Han, Lu

2013-07-01

The chemical industry is a major source of various pollution accidents. Improving the management level of risk sources for pollution accidents has become an urgent demand for most industrialized countries. In pollution accidents, the released chemicals harm the receptors to some extent depending on their sensitivity or susceptibility. Therefore, identifying the potential risk sources from such a large number of chemical enterprises has become pressingly urgent. Based on the simulation of the whole accident process, a novel and expandable identification method for risk sources causing water pollution accidents is presented. The newly developed approach, by analyzing and stimulating the whole process of a pollution accident between sources and receptors, can be applied to identify risk sources, especially on the nationwide scale. Three major types of losses, such as social, economic and ecological losses, were normalized, analyzed and used for overall consequence modeling. A specific case study area, located in a chemical industry park (CIP) along the Yangtze River in Jiangsu Province, China, was selected to test the potential of the identification method. The results showed that there were four risk sources for pollution accidents in this CIP. Aniline leakage in the HS Chemical Plant would lead to the most serious impact on the surrounding water environment. This potential accident would severely damage the ecosystem up to 3.8 km downstream of Yangtze River, and lead to pollution over a distance stretching to 73.7 km downstream. The proposed method is easily extended to the nationwide identification of potential risk sources.

Bioindication of total toxicity and teratogenicity of bottom deposits and soils from regions with different degree of the influence of the Chernobyl NPP accident using the developing embryos of grey sea urchins

International Nuclear Information System (INIS)

Grishchenko, O.M.; Chumak, V.K.; Grishchenko, S.O.; Rachins'kij, V.N.; Grishchenko, N.O.

1992-01-01

The changes (for 1983-90) in total toxicity and teratogenicity of bottom deposits in the Dnieper cascade and soil from some regions of the Ukraine with unequal degree of the influence of the Chernobyl NPP accident have been comparatively studied using developing embryos and larvae of grey sea urchins which are very sensitive to the unfavourable effect of radionuclides, many chemical technogenic factors. (author)

Studies of radiation and chemical toxicity. Progress report

International Nuclear Information System (INIS)

1986-01-01

Annual report for the Studies of Radiation and Chemical Toxicity Program at the University of Rochester is presented. Progress is reported on four projects: Neurobehavorial Toxicity of Organometallic Fuel Additives, Mechanisms of Permanent and Delayed Pathologic Effects of Ionizing Radiation, Solid State Radiation Chemistry of the DNA Backbone, and Pulmonary Biochemistry

Chemical Hazards and Safety Issues in Fusion Safety Design

International Nuclear Information System (INIS)

Cadwallader, L.C.

2003-01-01

Radiological inventory releases have dominated accident consequences for fusion; these consequences are important to analyze and are generally the most severe result of a fusion facility accident event. However, the advent of, or plan for, large-scale usage of some toxic materials poses the additional hazard of chemical exposure from an accident event. Examples of toxic chemicals are beryllium for magnetic fusion and fluorine for laser fusion. Therefore, chemical exposure consequences must also be addressed in fusion safety assessment. This paper provides guidance for fusion safety analysis. US Department of Energy (DOE) chemical safety assessment practices for workers and the public are reviewed. The US Environmental Protection Agency (EPA) has published some guidance on public exposure to releases of mixtures of chemicals, this guidance has been used to create an initial guideline for treating mixed radiological and toxicological releases in fusion; for example, tritiated hazardous dust from a tokamak vacuum vessel. There is no convenient means to judge the hazard severity of exposure to mixed materials. The chemical fate of mixed material constituents must be reviewed to determine if there is a separate or combined radiological and toxicological carcinogenesis, or if other health threats exist with radiological carcinogenesis. Recommendations are made for fusion facility chemical safety evaluation and safety guidance for protecting the public from chemical releases, since such levels are not specifically identified in the DOE fusion safety standard

Management of low and intermediate level radioactive wastes with regard to their chemical toxicity

International Nuclear Information System (INIS)

2002-12-01

A preliminary overview is provided of management options for low and intermediate level radioactive waste (LILW) with regard to its chemical toxicity. In particular, the following issues are identified and described associated with the management and safe disposal of chemically toxic materials in LILW: the origin and characteristics; the regulatory approaches; the pre-disposal management; the disposal; the safety assessment. Also included are: regulatory framework for chemically toxic low level wastes in the USA; pre-disposal processing options for LILW containing chemically toxic components; example treatment technologies for LILW containing chemically toxic components and safety assessment case studies for Germany, Belgium, France and Sweden

Response to a Chemical Incident or Accident -- Who Is In Charge?

National Research Council Canada - National Science Library

Briggs, Darryl J

2007-01-01

.... The thesis of the paper is as follows: Combatant Commanders and the Services must have specific guidance and appropriate authorities to be able to effectively manage a Chemical Accident and Incident Response and Assistance (CAIRA...

Construction of a technique plan repository and evaluation system based on AHP group decision-making for emergency treatment and disposal in chemical pollution accidents

International Nuclear Information System (INIS)

Shi, Shenggang; Cao, Jingcan; Feng, Li; Liang, Wenyan; Zhang, Liqiu

2014-01-01

Highlights: • Different chemical pollution accidents were simplified using the event tree analysis. • Emergency disposal technique plan repository of chemicals accidents was constructed. • The technique evaluation index system of chemicals accidents disposal was developed. • A combination of group decision and analytical hierarchy process (AHP) was employed. • Group decision introducing similarity and diversity factor was used for data analysis. - Abstract: The environmental pollution resulting from chemical accidents has caused increasingly serious concerns. Therefore, it is very important to be able to determine in advance the appropriate emergency treatment and disposal technology for different types of chemical accidents. However, the formulation of an emergency plan for chemical pollution accidents is considerably difficult due to the substantial uncertainty and complexity of such accidents. This paper explains how the event tree method was used to create 54 different scenarios for chemical pollution accidents, based on the polluted medium, dangerous characteristics and properties of chemicals involved. For each type of chemical accident, feasible emergency treatment and disposal technology schemes were established, considering the areas of pollution source control, pollutant non-proliferation, contaminant elimination and waste disposal. Meanwhile, in order to obtain the optimum emergency disposal technology schemes as soon as the chemical pollution accident occurs from the plan repository, the technique evaluation index system was developed based on group decision-improved analytical hierarchy process (AHP), and has been tested by using a sudden aniline pollution accident that occurred in a river in December 2012

Construction of a technique plan repository and evaluation system based on AHP group decision-making for emergency treatment and disposal in chemical pollution accidents

Energy Technology Data Exchange (ETDEWEB)

Shi, Shenggang [College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083 (China); College of Chemistry, Baotou Teachers’ College, Baotou 014030 (China); Cao, Jingcan; Feng, Li; Liang, Wenyan [College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083 (China); Zhang, Liqiu, E-mail: zhangliqiu@163.com [College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083 (China)

2014-07-15

Highlights: • Different chemical pollution accidents were simplified using the event tree analysis. • Emergency disposal technique plan repository of chemicals accidents was constructed. • The technique evaluation index system of chemicals accidents disposal was developed. • A combination of group decision and analytical hierarchy process (AHP) was employed. • Group decision introducing similarity and diversity factor was used for data analysis. - Abstract: The environmental pollution resulting from chemical accidents has caused increasingly serious concerns. Therefore, it is very important to be able to determine in advance the appropriate emergency treatment and disposal technology for different types of chemical accidents. However, the formulation of an emergency plan for chemical pollution accidents is considerably difficult due to the substantial uncertainty and complexity of such accidents. This paper explains how the event tree method was used to create 54 different scenarios for chemical pollution accidents, based on the polluted medium, dangerous characteristics and properties of chemicals involved. For each type of chemical accident, feasible emergency treatment and disposal technology schemes were established, considering the areas of pollution source control, pollutant non-proliferation, contaminant elimination and waste disposal. Meanwhile, in order to obtain the optimum emergency disposal technology schemes as soon as the chemical pollution accident occurs from the plan repository, the technique evaluation index system was developed based on group decision-improved analytical hierarchy process (AHP), and has been tested by using a sudden aniline pollution accident that occurred in a river in December 2012.

Investigation of the potential influence of production treatment chemicals on produced water toxicity

International Nuclear Information System (INIS)

Stine, E.R.; Gala, W.R.; Henry, L.R.

1993-01-01

Production treatment chemicals represent a diverse collection of chemical classes, added at various points from the wellhead to the final flotation cell, to prevent operational upsets and enhance the separation of oil from water. Information in the literature indicates that while many treatment chemicals are thought to partition into oil and not into the produced water, there are cases where a sufficiently water soluble treatment chemical is added at high enough concentrations to suggest that the treatment chemical may add to the aquatic toxicity of the produced water. A study was conducted to evaluate the potential effect of production treatment chemicals on the toxicity of produced waters using the US EPA Seven-day Mysidopsis bahia Survival, Growth and Fecundity Test. Samples of produced water were collected and tested for toxicity from three platforms under normal operating conditions, followed by repeated sampling and testing after a 72-hour period in which treatment chemical usage was discontinued, to the degree possible. Significant reductions in produced water toxicity were observed for two of the three platforms tested following either cessation of treatment chemical usage, or by comparing the toxicity of samples collected upstream and downstream of the point of treatment chemical addition

Management of risks in the chemical and nuclear areas

International Nuclear Information System (INIS)

Venuti, G.C.; Frullani, S.; Pocchiari, F.; Rogani, A.; Silano, V.; Tabet, E.; Zapponi, G.

1984-01-01

A comparative overview is provided of some major aspects concerning assessment and management of chemical and nuclear risks arising as a consequence of accidents. Statutory procedures for constructing and running nuclear and chemical plants in Italy are discussed in detail. Special attention is given to the major changes that are likely to occur after the adoption of the EEC Council Directive 82/501, designed to prevent major accidents which might result from certain industrial activities and to limit their consequences for humans and their environment. Present status and future trends of accident analysis and risk assessment are also dealt with, and special emphasis is placed on aspects common to both nuclear and chemical plants. Lastly, managerial aspects of contingency planning for, and response to, emergencies and accidents involving toxic chemical and/or ionizing radiations are examined with the aim of identifying more critical steps. (author)

Toxic chemicals: risk prevention through use reduction

National Research Council Canada - National Science Library

Higgins, Thomas E; Sachdev, Jayanti A; Engleman, Stephen A

2011-01-01

"Catastrophic events such as the Bhopal, India tragedy and rising incidences of cancer in areas neighboring industrial facilities have heightened concern over the use of toxic chemicals in manufacturing and industry...

[Assessment of the relationship of properties of chemical compounds and their toxicity to a unified hygienic standardization for chemicals].

Science.gov (United States)

Trushkov, V F; Perminov, K A; Sapozhnikova, V V; Ignatova, O L

2013-01-01

The connection of thermodynamic properties and parameters of toxicity of chemical substances was determined. Obtained data are used for the evaluation of toxicity and hygienic rate setting of chemical compounds. The relationship between enthalpy and toxicity of chemical compounds has been established. Orthogonal planning of the experiment was carried out in the course of the investigations. Equation of unified hygienic rate setting in combined, complex, conjunct influence on the organism is presented. Prospects of determination of toxicity and methodology of unified hygienic rate setting in combined, complex, conjunct influence on the organism are presented

Emergency preparedness and response in case of a fire accident with (UF6) packages tracking Suez Canal

International Nuclear Information System (INIS)

Salama, M.

2004-01-01

Egypt has a unique problem - the Suez Canal. Radioactive cargo passing regularly through the canal carrying new and spent reactor fuel. Moreover there are also about 1000 metric tons of uranium hexaflouride (UF6) passing through the canal every year. In spite of all precautions taken in the transportation, accidents with packages containing (UF 6 ) and shipped through the Suez Canal, accidents may arise even though the probability is minimal. These accidents, may be accompanied by injuries or death of persons and damage to property. Due to the radiation and criticality hazards of (UF 6 ) and its high risk of chemical toxicity. The probability of a fire accident with a cargo carrying (UF 6 ) during its crossing the Suez Canal can cause serious chemical toxic and radiological hazards, particularly if the accident occurred close or near to one of the three densely populated cities (Port-Said, Ismailia, and Suez), which are located along the Suez Canal, west bank. The government of Egypt has elaborated a national radiological emergency plan inorder to face probable radiological accidents, which may be arised inside the country. Arrangements have been also elaborated for the medical care of any persons who, might be injured or contaminated, or who, have been exposed to severe radiation doses. The motivation of the present paper was undertaken to visualize a fire accident scenario occurring in industrial packages containing UF6 on board of a Cargo crossing the Suez Canal near Port-Said City. The accident scenario and emergency response actions taken during the different phases of the accident are going to be presented and discussed. The proposed emergency response actions taken to face the accident are going to be also presented. The work presented had revealed the importance of public awareness will be needed for populations located in densely populated areas along Suez Canal bank inorder to react timely and effectively to avoid the toxic and radiological hazards

Toxic neuropathies: Mechanistic insights based on a chemical perspective.

Science.gov (United States)

LoPachin, Richard M; Gavin, Terrence

2015-06-02

2,5-Hexanedione (HD) and acrylamide (ACR) are considered to be prototypical among chemical toxicants that cause central-peripheral axonopathies characterized by distal axon swelling and degeneration. Because the demise of distal regions was assumed to be causally related to the onset of neurotoxicity, substantial effort was devoted to deciphering the respective mechanisms. Continued research, however, revealed that expression of the presumed hallmark morphological features was dependent upon the daily rate of toxicant exposure. Indeed, many studies reported that the corresponding axonopathic changes were late developing effects that occurred independent of behavioral and/or functional neurotoxicity. This suggested that the toxic axonopathy classification might be based on epiphenomena related to dose-rate. Therefore, the goal of this mini-review is to discuss how quantitative morphometric analyses and the establishment of dose-dependent relationships helped distinguish primary, mechanistically relevant toxicant effects from non-specific consequences. Perhaps more importantly, we will discuss how knowledge of neurotoxicant chemical nature can guide molecular-level research toward a better, more rational understanding of mechanism. Our discussion will focus on HD, the neurotoxic γ-diketone metabolite of the industrial solvents n-hexane and methyl-n-butyl ketone. Early investigations suggested that HD caused giant neurofilamentous axonal swellings and eventual degeneration in CNS and PNS. However, as our review will point out, this interpretation underwent several iterations as the understanding of γ-diketone chemistry improved and more quantitative experimental approaches were implemented. The chemical concepts and design strategies discussed in this mini-review are broadly applicable to the mechanistic studies of other chemicals (e.g., n-propyl bromine, methyl methacrylate) that cause toxic neuropathies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Radiation-dosimetry and chemical-toxicity considerations for 99Tc

International Nuclear Information System (INIS)

Coffey, J.L.; Hayes, R.L.; Rafter, J.J.; Watson, E.E.; Carlton, J.E.

1982-01-01

Technetium-99 (T/sub 1/2/ = 2.13 x 10 5 y) is produced in the fission of 235 U and 239 Pu. Technitium-99 has been found to contaminate some areas of the uranium re-enrichment process. ICRP-30 Part 2 gives the Annual Limit on Intake (ALI) for 99 Tc as 2 x 10 8 Bq (5.4 mCi) for class D inhaled material (IC80). The ICRP states clearly that ALIs are based on radiation risk only and that chemical toxicity is not considered (IC79). No data were found on the chemical toxicity of 99 Tc, possibly because there are no stable isotopes of technetium with which to study the toxicity, although, because of its long T/sub 1/2/, 99 Tc can, for all practical purposes, be considered stable. The ALI values for 99 Tc are based on data obtained using high specific activity /sup 99m/Tc (T/sub 1/2/ = 6 h) and /sup 95m/Tc (T/sub 1/2/ = 61 days). Since the specific activities of 99 Tc and Na 99 TcO 4 are quite low (17 mCi/g and 9 mCi/g, respectively) and 99 Tc is available in abundant supply, we have attempted to assess the relative radiation and chemical hazards that are associated with this radionuclide. The approach in this study was (1) to study the effect of chemical dose on the whole body retention of 99 Tc sodium pertechnetate in rats and to relate these effects to the radiation dose and the ALI and (2) to compare the chemical toxicity of 99 Tc sodium pertechnetate with the ALI at different chemical dose levels

76 FR 64022 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting

Science.gov (United States)

2011-10-17

... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting AGENCY: Environmental Protection Agency (EPA). ACTION: Lifting of Administrative Stay for Hydrogen Sulfide. SUMMARY: EPA is announcing... (EPCRA) section 313 toxic chemical release reporting requirements for hydrogen sulfide (Chemical...

Modern concepts of treatment and prevention of chemical injuries.

Science.gov (United States)

Edlich, Richard F; Farinholt, Heidi-Marie A; Winters, Kathryne L; Britt, L D; Long, William B; Werner, Charles L; Gubler, K Dean

2005-01-01

Chemical injuries are commonly encountered following exposure to acids and alkali, including hydrofluoric acid, formic acid, anhydrous ammonia, cement, and phenol. Other specific agents that cause chemical burns include white phosphorus, elemental metals, nitrates, hydrocarbons, and tar. Even though there are more than 65,000 chemicals available on the market, and an estimated 60,000 new chemicals produced each year, the potential deleterious effects of these chemicals on humans are still unknown. The Superfund Amendments and Reauthorization Act contains extensive provisions for emergency planning and the rights of communities to know about toxic chemical releases. Since 1990, the Agency for Toxic Substances and Disease Registry (ATSDR) has maintained an active, state-based Hazardous Substances Emergency Events Surveillance (HSEES) system to describe the public health consequences risked by access to hazardous chemicals. Most chemical agents damage the skin by producing a chemical reaction rather than hyperthermic injury. Although some chemicals produce considerable heat as a result of an exothermic reaction when they come in contact with water, their ability to produce direct chemical changes on the skin accounts for the most skin injury. Specific chemical changes depend on the agent, including acids, alkalis, corrosives, oxidizing and reducing agents, desiccants, vesicants, and protoplasmic poisons. The concentration of toxic agent and duration of its contact primarily determine degree of skin destruction. Hazardous materials (hazmats) are substances that may injure life and damage the environment if improperly handled. HAZMAT accidents are particularly dangerous for responding personnel, who are in danger from the moment of arrival on the scene until containment of the accident. Consequently, the Superfund Amendment and Reauthorization Act mandates community preparedness for dealing with hazmat accidents. Paramedics and members of the hazmat response team

COMPUTER SUPPORT SYSTEMS FOR ESTIMATING CHEMICAL TOXICITY: PRESENT CAPABILITIES AND FUTURE TRENDS

Science.gov (United States)

Computer Support Systems for Estimating Chemical Toxicity: Present Capabilities and Future Trends A wide variety of computer-based artificial intelligence (AI) and decision support systems exist currently to aid in the assessment of toxicity for environmental chemicals. T...

Consequences of potential accidents in heavy water plants

International Nuclear Information System (INIS)

Croitoru, C.; Lazar, R.E.; Preda, I.A.; Dumitrescu, M.

2002-01-01

Heavy water plants achieve the primary isotopic concentration by H 2 O-H 2 S chemical exchange. In these plants are stored large quantities of hydrogen sulphide (high toxic, corrosive, flammable and explosive) maintained in process at relative high temperatures and pressures. It is required an assessment of risks associated with the potential accidents. The paper presents adopted model for quantitative consequences assessment in heavy water plants. Following five basic steps are used to identify the risks involved in plants operation: hazard identification, accident sequences development, H 2 S emissions calculus, dispersion analyses and consequences determination. A brief description of each step and some information from risk assessment for our heavy water pilot plant are provided. Accident magnitude, atmospheric conditions and population density in studied area were accounted for consequences calculus. (author)

Acute toxicity of fire control chemicals to Daphnia magna(Straus) and Selenastrum capricornutum(Printz)

Science.gov (United States)

McDonald, Susan F.; Hamilton, Steven J.; Buhl, Kevin J.; Heisinger, James F.

1996-01-01

Acute toxicity tests were conducted exposingDaphnia magnaStraus (daphnid) in soft and hard reconstituted waters (hardness 42 and 162 mg/liter as CaCO3, respectively), andSelenastrum capricornutumPrintz (algae) in ASTM algal assay medium (hardness 15 mg/liter as CaCO3) to fire retardants Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F, and foam suppressants Phos-Chek WD-881 and Silv-Ex. The chemicals were slightly toxic to practically harmless to daphnids and moderately toxic to algae. Water quality did not consistently alter the toxicity of the test chemicals to daphnids. The most toxic chemical to daphnids was Silv-Ex (48-hr EC507 mg/liter in soft and hard waters), whereas the least toxic chemical to daphnids was Fire-Trol LCG-R (48-hr EC50848 mg/liter in soft water, 813 mg/liter in hard water). The most toxic chemical to algae was Fire-Trol LCG-R (96-hr IC5010 mg/liter), and the least toxic chemical was Phos-Chek D75-F (96-hr IC5079 mg/liter). Un-ionized ammonia concentrations near the EC50or IC50value in tests with the Fire-Trol compounds were frequently equal to or above reported LC50un-ionized ammonia concentrations. Un-ionized ammonia concentrations in tests with Phos-Chek D75-F were low, thus other toxic components present in the compounds probably contributed to the toxicity. When compared to the daphnids tested in ASTM soft water, the Fire-Trol compounds were most toxic to algae, whereas Phos-Chek D75-F and the foam suppressants were most toxic to daphnids. The results of these tests are comparable to those obtained from research conducted in other laboratories with the same species and similar chemicals. Accidental entry of fire-fighting chemicals into aquatic environments could adversely affect algae and aquatic invertebrates, thus disrupting ecosystem function.

Chemical dosimetry system for criticality accidents.

Science.gov (United States)

Miljanić, Saveta; Ilijas, Boris

2004-01-01

Ruder Bosković Institute (RBI) criticality dosimetry system consists of a chemical dosimetry system for measuring the total (neutron + gamma) dose, and a thermoluminescent (TL) dosimetry system for a separate determination of the gamma ray component. The use of the chemical dosemeter solution chlorobenzene-ethanol-trimethylpentane (CET) is based on the radiolytic formation of hydrochloric acid, which protonates a pH indicator, thymolsulphonphthalein. The high molar absorptivity of its red form at 552 nm is responsible for a high sensitivity of the system: doses in the range 0.2-15 Gy can be measured. The dosemeter has been designed as a glass ampoule filled with the CET solution and inserted into a pen-shaped plastic holder. For dose determinations, a newly constructed optoelectronic reader has been used. The RBI team took part in the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002, with the CET dosimetry system. For gamma ray dose determination TLD-700 TL detectors were used. The results obtained with CET dosemeter show very good agreement with the reference values.

Emergency preparedness and response in case of a fire accident with (UF{sub 6}) packages tracking Suez Canal

Energy Technology Data Exchange (ETDEWEB)

Salama, M. [National Center for Nuclear Safety and Radiation Control (NCNSRC), Nasr City, Cairo (Egypt)

2004-07-01

Egypt has a unique problem - the Suez Canal. Radioactive cargo passing regularly through the canal carrying new and spent reactor fuel. Moreover there are also about 1000 metric tons of uranium hexaflouride (UF6) passing through the canal every year. In spite of all precautions taken in the transportation, accidents with packages containing (UF{sub 6}) and shipped through the Suez Canal, accidents may arise even though the probability is minimal. These accidents, may be accompanied by injuries or death of persons and damage to property. Due to the radiation and criticality hazards of (UF{sub 6}) and its high risk of chemical toxicity. The probability of a fire accident with a cargo carrying (UF{sub 6}) during its crossing the Suez Canal can cause serious chemical toxic and radiological hazards, particularly if the accident occurred close or near to one of the three densely populated cities (Port-Said, Ismailia, and Suez), which are located along the Suez Canal, west bank. The government of Egypt has elaborated a national radiological emergency plan inorder to face probable radiological accidents, which may be arised inside the country. Arrangements have been also elaborated for the medical care of any persons who, might be injured or contaminated, or who, have been exposed to severe radiation doses. The motivation of the present paper was undertaken to visualize a fire accident scenario occurring in industrial packages containing UF6 on board of a Cargo crossing the Suez Canal near Port-Said City. The accident scenario and emergency response actions taken during the different phases of the accident are going to be presented and discussed. The proposed emergency response actions taken to face the accident are going to be also presented. The work presented had revealed the importance of public awareness will be needed for populations located in densely populated areas along Suez Canal bank inorder to react timely and effectively to avoid the toxic and radiological

Temperature influence on chemical toxicity to aquatic organisms

International Nuclear Information System (INIS)

Cairns, J. Jr.; Heath, A.G.; Parker, B.C.

1975-01-01

The literature on the effects of temperature on chemical toxicity to aquatic animals and microorganisms is reviewed. Microbial photosynthesis and respiration is briefly discussed. It is concluded that there is a paucity of information on the inter-relations of temperature and toxicants to algae, bacteria, and protozoa and that standards based on the in situ response of indigenous organisms to specific discharge areas should be developed

Chemical Plant Accidents in a Nuclear Hydrogen Generation Scheme

International Nuclear Information System (INIS)

Brown, Nicholas R.; Revankar, Shripad T.

2011-01-01

A high temperature nuclear reactor (HTR) could be used to drive a steam reformation plant, a coal gasification facility, an electrolysis plant, or a thermochemical hydrogen production cycle. Most thermochemical cycles are purely thermodynamic, and thus achieve high thermodynamic efficiency. HTRs produce large amounts of heat at high temperature (1100 K). Helium-cooled HTRs have many passive, or inherent, safety characteristics. This inherent safety is due to the high design basis limit of the maximum fuel temperature. Due to the severity of a potential release, containment of fission products is the single most important safety issue in any nuclear reactor facility. A HTR coupled to a chemical plant presents a complex system, due primarily to the interactive nature of both plants. Since the chemical plant acts as the heat sink for the nuclear reactor, it important to understand the interaction and feedback between the two systems. Process heat plants and HTRs are generally very different. Some of the major differences include: time constants of plants, safety standards, failure probability, and transient response. While both the chemical plant and the HTR are at advanced stages of testing individually, no serious effort has been made to understand the operation of the integrated system, especially during accident events that are initiated in the chemical plant. There is a significant lack of knowledge base regarding scaling and system integration for large scale process heat plants coupled to HTRs. Consideration of feedback between the two plants during time-dependent scenarios is absent from literature. Additionally, no conceptual studies of the accidents that could occur in either plant and impact the entire coupled system are present in literature

An endothermic chemical process facility coupled to a high temperature reactor. Part I: Proposed accident scenarios within the chemical plant

International Nuclear Information System (INIS)

Brown, Nicholas R.; Seker, Volkan; Revankar, Shripad T.; Downar, Thomas J.

2012-01-01

Highlights: ► The paper identifies possible transient and accident scenarios in a coupled PBMR and thermochemical sulfur cycle based hydrogen plant. ► Key accidents scenarios were investigated through qualitative reasoning. ► The accidents were found to constitute loss of heat sink event for the nuclear reactor. - Abstract: Hydrogen generation using a high temperature nuclear reactor as a thermal driving vector is a promising future option for energy carrier production. In this scheme, the heat from the nuclear reactor drives an endothermic water-splitting plant, via coupling, through an intermediate heat exchanger. Quantitative study of the possible operational or accident events within the coupled plant is largely absent from the literature. In this paper, seven unique case studies are proposed based on a thorough review of possible events. The case studies are: (1) feed flow failure from one section of the chemical plant to another with an accompanying parametric study of the temperature in an individual reaction chamber, (2) product flow failure (recycle) within the chemical plant, (3) rupture or explosion within the chemical plant, (4) nuclear reactor helium inlet overcooling due to a process holding tank failure, (5) helium inlet overcooling as an anticipated transient without emergency nuclear reactor shutdown, (6) total failure of the chemical plant, (7) control rod insertion in the nuclear reactor. The qualitative parameters of each case study are outlined as well as the basis in literature. A previously published modeling scheme is described and adapted for application as a simulation platform for these transient events. The results of the quantitative case studies are described within part II of this paper.

Construction of a technique plan repository and evaluation system based on AHP group decision-making for emergency treatment and disposal in chemical pollution accidents.

Science.gov (United States)

Shi, Shenggang; Cao, Jingcan; Feng, Li; Liang, Wenyan; Zhang, Liqiu

2014-07-15

The environmental pollution resulting from chemical accidents has caused increasingly serious concerns. Therefore, it is very important to be able to determine in advance the appropriate emergency treatment and disposal technology for different types of chemical accidents. However, the formulation of an emergency plan for chemical pollution accidents is considerably difficult due to the substantial uncertainty and complexity of such accidents. This paper explains how the event tree method was used to create 54 different scenarios for chemical pollution accidents, based on the polluted medium, dangerous characteristics and properties of chemicals involved. For each type of chemical accident, feasible emergency treatment and disposal technology schemes were established, considering the areas of pollution source control, pollutant non-proliferation, contaminant elimination and waste disposal. Meanwhile, in order to obtain the optimum emergency disposal technology schemes as soon as the chemical pollution accident occurs from the plan repository, the technique evaluation index system was developed based on group decision-improved analytical hierarchy process (AHP), and has been tested by using a sudden aniline pollution accident that occurred in a river in December 2012. Copyright © 2014 Elsevier B.V. All rights reserved.

Toxicity studies of drugs and chemicals in animals: An overview

OpenAIRE

S. Saganuwan

2017-01-01

Toxicity study is the investigation of either short or long-term toxic effects of a drug or chemical on animals. The toxicity is dose-dependent as asserted by Paracelsus over 500 years ago. However, short-term toxic effect is determined using median lethal dose (LD50) first introduced by Trevan in 1927 and revised many times. Presently there is a growing preponderance of rejection of scientific papers on acute toxicity study, simply because of the belief that in the current hazard and safety ...

Base catalyzed decomposition of toxic and hazardous chemicals

International Nuclear Information System (INIS)

Rogers, C.J.; Kornel, A.; Sparks, H.L.

1991-01-01

There are vast amounts of toxic and hazardous chemicals, which have pervaded our environment during the past fifty years, leaving us with serious, crucial problems of remediation and disposal. The accumulation of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), ''dioxins'' and pesticides in soil sediments and living systems is a serious problem that is receiving considerable attention concerning the cancer-causing nature of these synthetic compounds.US EPA scientists developed in 1989 and 1990 two novel chemical Processes to effect the dehalogenation of chlorinated solvents, PCBs, PCDDs, PCDFs, PCP and other pollutants in soil, sludge, sediment and liquids. This improved technology employs hydrogen as a nucleophile to replace halogens on halogenated compounds. Hydrogen as nucleophile is not influenced by steric hinderance as with other nucleophile where complete dehalogenation of organohalogens can be achieved. This report discusses catalyzed decomposition of toxic and hazardous chemicals

Consequence of potential accidents in heavy water plants

International Nuclear Information System (INIS)

Croitoru, C.; Lazar, R.E.; Preda, I.A.; Dumitrescu, M.

1998-01-01

Heavy water plants realize the primary isotopic concentrations of water using H 2 O-H 2 S chemical exchange and they are chemical plants. As these plants are handling and spreading large quantities of hydrogen sulphide (high toxic, corrosive, flammable and explosive as) maintained in the process at relative high temperatures and pressures, it is required an assessing of risks associated with the potential accidents. The H 2 S released in atmosphere as a result of an accident will have negative consequences to property, population and environment. This paper presents a model of consequences quantitative assessment and its outcome for the most dangerous accident in heavy water plants. Several states of the art risk based methods were modified and linked together to form a proper model for this analyse. Five basic steps to identify the risks involved in operating the plants are followed: hazard identification, accident sequence development, H 2 S emissions calculus, dispersion analyses and consequences determination. A brief description of each step and some information of analysis results are provided. The accident proportions, the atmospheric conditions and the population density in the respective area were accounted for consequences calculus. The specific results of the consequences analysis allow to develop the plant's operating safety requirements so that the risk remain at an acceptable level. (authors)

Oxidative stress in chemical toxicity

Energy Technology Data Exchange (ETDEWEB)

Kappus, H.

1986-05-01

The toxic effect of compounds which undergo redox cycling enzymatic one-electron reduction are reviewed. First of all, the enzymatic reduction of these compounds leads to reactive intermediates, mainly radicals which react with oxygen, whereby superoxide anion radicals are formed. Further oxygen metabolites are hydrogen peroxide, singlet oxygen and hydroxyl radicals. The role of these oxygen metabolites in toxicity is discussed. The occurrence of lipid peroxidation during redox cycling of quinonoide compounds, e.g., adriamycin, and the possible relationship to their toxicity is critically evaluated. It is shown that iron ions play a crucial role in lipid peroxidation induced by redox cycling compounds. DNA damage by metal chelates, e.g., bleomycin, is discussed on the basis of findings that enzymatic redox cycling of a bleomycin-iron complex has been observed. The involvement of hydroxyl radicals in bleomycin-induced DNA damage occurring during redox cycling in cell nuclei is claimed. Redox cycling of other substances, e.g., aromatic amines, is discussed in relation to carcinogenesis. Other chemical groups, e.g., nitroaromatic compounds, hydroxylamines and azo compounds are included. Other targets for oxygen radical attack, e.g., proteins, are also dealt with. It is concluded that oxygen radical formation by redox cycling may be a critical event in toxic effects of several compounds if the protective mechanisms of cells are overwhelmed.

A FLUORESCENCE BASED ASSAY FOR DNA DAMAGE INDUCED BY TOXIC INDUSTRIAL CHEMICALS

Science.gov (United States)

One of the reported effects for exposure to many of the toxic industrial chemicals is DNA damage. The present study describes a simple, rapid and innovative assay to detect DNA damage resulting from exposure of surrogate DNA to toxic industrial chemicals (acrolein, allylamine, ch...

Toxics Release Inventory Chemical Hazard Information Profiles (TRI-CHIP) Dataset

Data.gov (United States)

U.S. Environmental Protection Agency — The Toxics Release Inventory (TRI) Chemical Hazard Information Profiles (TRI-CHIP) dataset contains hazard information about the chemicals reported in TRI. Users can...

Toxic Industrial Chemical Tests of Resistance to Permeation by Protective Suits

National Research Council Canada - National Science Library

Klemperer, Elizabeth

2005-01-01

A Natick program to select and test protective materials for soldiers and first responders who face a threat from chemical accidents or terrorist attacks was applied under Congressional legislation...

Safety assessment of VHTR hydrogen production system against fire, explosion and acute toxicity

International Nuclear Information System (INIS)

Murakami, Tomoyuki; Nishihara, Tetsuo; Kunitomi, Kazuhiko

2008-01-01

The Japan Atomic Energy Agency has been developing a nuclear hydrogen production system by using heat from the Very High Temperature Reactor (VHTR). This system will handle a large amount of combustible gas and toxic gas. The risk from fire, explosion and acute toxic exposure caused by an accident involving chemical material release in a hydrogen production system is assessed. It is important to ensure the safety of the nuclear plant, and the risks for public health should be sufficiently small. This report provides the basic policy for the safety evaluation in cases of accident involving fire, explosion and toxic material release in a hydrogen production system. Preliminary safety analysis of a commercial-sized VHTR hydrogen production system, GTHTR300C, is performed. This analysis provides us with useful information on the separation distance between a nuclear plant and a hydrogen production system and a prospect that an accident in a hydrogen production system does not significantly increase the risks of the public. (author)

The underlying toxicological mechanism of chemical mixtures: A case study on mixture toxicity of cyanogenic toxicants and aldehydes to Photobacterium phosphoreum

International Nuclear Information System (INIS)

Tian, Dayong; Lin, Zhifen; Zhou, Xianghong; Yin, Daqiang

2013-01-01

Intracellular chemical reaction of chemical mixtures is one of the main reasons that cause synergistic or antagonistic effects. However, it still remains unclear what the influencing factors on the intracellular chemical reaction are, and how they influence on the toxicological mechanism of chemical mixtures. To reveal this underlying toxicological mechanism of chemical mixtures, a case study on mixture toxicity of cyanogenic toxicants and aldehydes to Photobacterium phosphoreum was employed, and both their joint effects and mixture toxicity were observed. Then series of two-step linear regressions were performed to describe the relationships between joint effects, the expected additive toxicities and descriptors of individual chemicals (including concentrations, binding affinity to receptors, octanol/water partition coefficients). Based on the quantitative relationships, the underlying joint toxicological mechanisms were revealed. The result shows that, for mixtures with their joint effects resulting from intracellular chemical reaction, their underlying toxicological mechanism depends on not only their interaction with target proteins, but also their transmembrane actions and their concentrations. In addition, two generic points of toxicological mechanism were proposed including the influencing factors on intracellular chemical reaction and the difference of the toxicological mechanism between single reactive chemicals and their mixtures. This study provided an insight into the understanding of the underlying toxicological mechanism for chemical mixtures with intracellular chemical reaction. - Highlights: • Joint effects of nitriles and aldehydes at non-equitoxic ratios were determined. • A novel descriptor, ligand–receptor interaction energy (E binding ), was employed. • Quantitative relationships for mixtures were developed based on a novel descriptor. • The underlying toxic mechanism was revealed based on quantitative relationships. • Two generic

The underlying toxicological mechanism of chemical mixtures: A case study on mixture toxicity of cyanogenic toxicants and aldehydes to Photobacterium phosphoreum

Energy Technology Data Exchange (ETDEWEB)

Tian, Dayong [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Department of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000 (China); Lin, Zhifen, E-mail: lzhifen@tongji.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Zhou, Xianghong [Department of Public Management, Tongji University, Shanghai 200092 (China); Yin, Daqiang [Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China)

2013-10-15

Intracellular chemical reaction of chemical mixtures is one of the main reasons that cause synergistic or antagonistic effects. However, it still remains unclear what the influencing factors on the intracellular chemical reaction are, and how they influence on the toxicological mechanism of chemical mixtures. To reveal this underlying toxicological mechanism of chemical mixtures, a case study on mixture toxicity of cyanogenic toxicants and aldehydes to Photobacterium phosphoreum was employed, and both their joint effects and mixture toxicity were observed. Then series of two-step linear regressions were performed to describe the relationships between joint effects, the expected additive toxicities and descriptors of individual chemicals (including concentrations, binding affinity to receptors, octanol/water partition coefficients). Based on the quantitative relationships, the underlying joint toxicological mechanisms were revealed. The result shows that, for mixtures with their joint effects resulting from intracellular chemical reaction, their underlying toxicological mechanism depends on not only their interaction with target proteins, but also their transmembrane actions and their concentrations. In addition, two generic points of toxicological mechanism were proposed including the influencing factors on intracellular chemical reaction and the difference of the toxicological mechanism between single reactive chemicals and their mixtures. This study provided an insight into the understanding of the underlying toxicological mechanism for chemical mixtures with intracellular chemical reaction. - Highlights: • Joint effects of nitriles and aldehydes at non-equitoxic ratios were determined. • A novel descriptor, ligand–receptor interaction energy (E{sub binding}), was employed. • Quantitative relationships for mixtures were developed based on a novel descriptor. • The underlying toxic mechanism was revealed based on quantitative relationships. • Two

Accidents, often the result of an 'uncontrolled business process' - a study in the (Dutch) chemical industry

NARCIS (Netherlands)

Sonnemans, P.J.M.; Körvers, P.M.W.; Brombacher, A.C.; Beek, van P.C.; Reinders, J.E.A.

2003-01-01

Often companies in the (petro-) chemical industry claim that all possible countermeasures against potential accidents have been taken and therefore accidents are unforeseeable. In this paper we question this statement by analysing the pre-warning signals (precursors) preceding a number of industrial

Evaluation of Chemical Warfare Agent Percutaneous Vapor Toxicity: Derivation of Toxicity Guidelines for Assessing Chemical Protective Ensembles.

Energy Technology Data Exchange (ETDEWEB)

Watson, A.P.

2003-07-24

Percutaneous vapor toxicity guidelines are provided for assessment and selection of chemical protective ensembles (CPEs) to be used by civilian and military first responders operating in a chemical warfare agent vapor environment. The agents evaluated include the G-series and VX nerve agents, the vesicant sulfur mustard (agent HD) and, to a lesser extent, the vesicant Lewisite (agent L). The focus of this evaluation is percutaneous vapor permeation of CPEs and the resulting skin absorption, as inhalation and ocular exposures are assumed to be largely eliminated through use of SCBA and full-face protective masks. Selection of appropriately protective CPE designs and materials incorporates a variety of test parameters to ensure operability, practicality, and adequacy. One aspect of adequacy assessment should be based on systems tests, which focus on effective protection of the most vulnerable body regions (e.g., the groin area), as identified in this analysis. The toxicity range of agent-specific cumulative exposures (Cts) derived in this analysis can be used as decision guidelines for CPE acceptance, in conjunction with weighting consideration towards more susceptible body regions. This toxicity range is bounded by the percutaneous vapor estimated minimal effect (EME{sub pv}) Ct (as the lower end) and the 1% population threshold effect (ECt{sub 01}) estimate. Assumptions of exposure duration used in CPE certification should consider that each agent-specific percutaneous vapor cumulative exposure Ct for a given endpoint is a constant for exposure durations between 30 min and 2 hours.

Microbial contamination and chemical toxicity of the Rio Grande

Directory of Open Access Journals (Sweden)

Valles Adrian

2004-04-01

Full Text Available Abstract Background The Rio Grande River is the natural boundary between U.S. and Mexico from El Paso, TX to Brownsville, TX. and is one of the major water resources of the area. Agriculture, farming, maquiladora industry, domestic activities, as well as differences in disposal regulations and enforcement increase the contamination potential of water supplies along the border region. Therefore, continuous and accurate assessment of the quality of water supplies is of paramount importance. The objectives of this study were to monitor water quality of the Rio Grande and to determine if any correlations exist between fecal coliforms, E. coli, chemical toxicity as determined by Botsford's assay, H. pylori presence, and environmental parameters. Seven sites along a 112-Km segment of the Rio Grande from Sunland Park, NM to Fort Hancock, TX were sampled on a monthly basis between January 2000 and December 2002. Results The results showed great variability in the number of fecal coliforms, and E. coli on a month-to-month basis. Fecal coliforms ranged between 0–106 CFU/100 ml while E. coli ranged between 6 to > 2419 MPN. H. pylori showed positive detection for all the sites at different times. Toxicity ranged between 0 to 94% of inhibition capacity (IC. Since values above 50% are considered to be toxic, most of the sites displayed significant chemical toxicity at different times of the year. No significant correlations were observed between microbial indicators and chemical toxicity. Conclusion The results of the present study indicate that the 112-Km segment of the Rio Grande river from Sunland Park, NM to Fort Hancock, TX exceeds the standards for contact recreation water on a continuous basis. In addition, the presence of chemical toxicity in most sites along the 112-Km segment indicates that water quality is an area of concern for the bi-national region. The presence of H. pylori adds to the potential health hazards of the Rio Grande. Since no

Radiation treatment of toxic chemicals

International Nuclear Information System (INIS)

Lee, M.J.; Jung, I.H.; Jo, S.K.

2010-01-01

Polychlorinated biphenyls (PCBs) were commercially produced from 1920s as complex mixtures containing multiple isomers for a variety of applications. They are very toxic, chemically stable and resist microbial, photochemical, chemical, and thermal degradation. The public, legal, and scientific concerns about PCBs arose from research indicating they were environmental contaminants that had a potential to adversely impact the environment, and, therefore, were undesirable as commercial products. Eventually, most producers reduced or stopped production of PCBs in the 1970s. Stockholm convention on POPs (Persistent Organic Pollutants), which was effective on May 2004 and 151 nations including Korea were joined on June 2005, asked to dispose of PCBs by 2028 with environmental friendly methods. Korean government also has declared to conduct by 2015. According to the Environmental law of Korea, over 2 ppm of PCBs has to be decomposed by legal methods of incineration and thermal destruction. But those are inapplicable owing to the environmental groups. KAERI(Korea Atomic Energy Research Institute) has recently developed a remarkable technology for radiation treatment of toxic chemicals including chlorides using an electron beam accelerator. Electron beam accelerator of 2.5 MeV energy and 100 kW power capacity was used to decompose of PCBs having been used as a commercial transformer oil for more than 30 years. The oil were irradiated with ∼ 0.1 percent of TEA (Triethyl Amin) to make chloride ion aparted off from the PCBs into precipitate at the conditions of normal temperature and pressure. The concentrations of PCBs were measured by GC (Gas Chromatography) with ECD (Electron Capture Detector) following the KS (Korean Standard) test procedure. Electron beam should be a useful tool for environmental conservation. Residual concentrations of PCBs after irradiation were depended on the absorption dose of electron beam energy. Advantages comparing to other methods such as

Identifying and designing chemicals with minimal acute aquatic toxicity.

Science.gov (United States)

Kostal, Jakub; Voutchkova-Kostal, Adelina; Anastas, Paul T; Zimmerman, Julie Beth

2015-05-19

Industrial ecology has revolutionized our understanding of material stocks and flows in our economy and society. For this important discipline to have even deeper impact, we must understand the inherent nature of these materials in terms of human health and the environment. This paper focuses on methods to design synthetic chemicals to reduce their intrinsic ability to cause adverse consequence to the biosphere. Advances in the fields of computational chemistry and molecular toxicology in recent decades allow the development of predictive models that inform the design of molecules with reduced potential to be toxic to humans or the environment. The approach presented herein builds on the important work in quantitative structure-activity relationships by linking toxicological and chemical mechanistic insights to the identification of critical physical-chemical properties needed to be modified. This in silico approach yields design guidelines using boundary values for physiochemical properties. Acute aquatic toxicity serves as a model endpoint in this study. Defining value ranges for properties related to bioavailability and reactivity eliminates 99% of the chemicals in the highest concern for acute aquatic toxicity category. This approach and its future implementations are expected to yield very powerful tools for life cycle assessment practitioners and molecular designers that allow rapid assessment of multiple environmental and human health endpoints and inform modifications to minimize hazard.

Toxic chemical risk acceptance criteria

International Nuclear Information System (INIS)

Craig, D.K.; Davis, J.; Lee, L.; Lein, P.; Omberg, S.

1992-01-01

This paper presents recommendations of a subcommittee of the Westinghouse M ampersand 0 Nuclear Facility Safety Committee concerning toxic chemical risk acceptance criteria. Two sets of criteria have been developed, one for use in the hazard classification of facilities, and the second for use in comparing risks in DOE non-reactor nuclear facility Safety Analysis Reports. The Emergency Response Planning Guideline (ERPG) values are intended to provide estimates of concentration ranges for specific chemicals above which exposure would be expected to lead to adverse heath effects of increasing severity for ERPG-1, -2, and -3s. The subcommittee recommends that criteria for hazard class or risk range be based on ERPGs for all chemicals. Probability-based Incremental Cancer Risk (ICR) criteria are recommended for additional analyses of risks from all known or suspected human carcinogens. Criteria are given for both on-site and off-site exposure. The subcommittee also recommends that the 5-minute peak concentration be compared with the relevant criterion with no adjustment for exposure time. Since ERPGs are available for only a limited number of chemicals, the subcommittee has developed a proposed hierarchy of concentration limit parameters for the different criteria

Toxicity of selected organic chemicals to the earthworm Eisenia fetida

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, E.F.; Loehr, R.C.; Malecki, M.R.; Milligan, D.L.; Durkin, P.R.

A number of methods recently have been developed to biologically evaluate the impact of man's activities on soil ecosystems. Two test methods, the 2-d contact test and the 14-d artificial soil test, were used to evaluate the impact of six major classes of organic chemicals on the earthworm Eisenia fetida (Savigny). Of the organic chemicals tested, phenols and amines were the most toxic to the worms, followed in descending order of toxicity by the substituted aromatics, halogenated aliphatics, polycyclic aromatic hydrocarbons, and phthalates. No relationship was found between earthworm toxicity as determined by the contact test and rat, Rattus norvegicus Berkenhout and mouse, Mus musculus L. LD/sub 50/ values. The physicochemical parameters of water solubility, vapor pressure, and octanol/water partition coefficient for the chemicals tested in the contact test did not show a significant relationship to the E. fetida LC/sub 50/ values. These studies indicate that: (i) earthworms can be a suitable biomonitoring tool to assist in measuring the impact of organic chemicals in wastes added to soils and (ii) contact and artificial soil tests can be useful in measuring biological impacts.

A Conceptual Framework for Predicting the Toxicity of Reactive Chemicals: Modeling Soft Electrophilicity

Science.gov (United States)

Although the literature is replete with QSAR models developed for many toxic effects caused by reversible chemical interactions, the development of QSARs for the toxic effects of reactive chemicals lacks a consistent approach. While limitations exit, an appropriate starting-point...

40 CFR 372.45 - Notification about toxic chemicals.

Science.gov (United States)

2010-07-01

...) If the person considers the specific identity of a toxic chemical in a mixture or trade name product... corporate or business interest (including common ownership or control), as described in § 372.38(f), operate...

Toxic industrial chemicals and chemical weapons: exposure, identification, and management by syndrome.

Science.gov (United States)

Tomassoni, Anthony J; French, Robert N E; Walter, Frank G

2015-02-01

Toxidromes aid emergency care providers in the context of the patient presenting with suspected poisoning, unexplained altered mental status, unknown hazardous materials or chemical weapons exposure, or the unknown overdose. The ability to capture an adequate chemical exposure history and to recognize toxidromes may reduce dependence on laboratory tests, speed time to delivery of specific antidote therapy, and improve selection of supportive care practices tailored to the etiologic agent. This article highlights elements of the exposure history and presents selected toxidromes that may be caused by toxic industrial chemicals and chemical weapons. Specific antidotes for toxidromes and points regarding their use, and special supportive measures, are presented. Copyright © 2015 Elsevier Inc. All rights reserved.

Sources of toxicity and exposure information for identifying chemicals of high concern to children

International Nuclear Information System (INIS)

Stone, Alex; Delistraty, Damon

2010-01-01

Due to the large number of chemicals in commerce without adequate toxicity characterization data, coupled with an ineffective federal policy for chemical management in the United States, many states are grappling with the challenge to identify toxic chemicals that may pose a risk to human health and the environment. Specific populations (e.g., children, elderly) are particularly sensitive to these toxic chemicals. In 2008, the Children's Safe Product Act (CSPA) was passed in Washington State. The CSPA included specific requirements to identify High Priority Chemicals (HPCs) and Chemicals of High Concern to Children (CHCCs). To implement this legislation, a methodology was developed to identify HPCs from authoritative scientific and regulatory sources on the basis of toxicity criteria. Another set of chemicals of concern was then identified from authoritative sources, based on their potential exposure to children. Exposure potential was evaluated by identifying chemicals detected in biomonitoring studies (i.e., human tissues), as well as those present in residential exposure media (e.g., indoor air, house dust, drinking water, consumer products). Accordingly, CHCCs were defined as HPCs that also appear in biomonitoring studies or relevant exposure media. For chemicals with unique Chemical Abstracts Service (CAS) numbers, we identified 2044 HPCs and 2219 chemicals with potential exposure to children, resulting in 476 CHCCs. The process of chemical identification is dynamic, so that chemicals may be added or subtracted as new information becomes available. Although beyond the scope of this paper, the 476 CHCCs will be prioritized in a more detailed assessment, based on the strength and weight of evidence of toxicity and exposure data. Our approach was developed to be flexible which allows the addition or removal of specific sources of toxicity or exposure information, as well as transparent to allow clear identification of inputs. Although the methodology was

Proposed chemical plant initiated accident scenarios in a sulphur-iodine cycle plant coupled to a pebble bed modular reactor

International Nuclear Information System (INIS)

Brown, N.R.; Revankar, S.T.; Seker, V.; Downar, Th.J.

2010-01-01

In the sulphur-iodine (S-I) cycle nuclear hydrogen generation scheme the chemical plant acts as the heat sink for the very high temperature nuclear reactor (VHTR). Thus, any accident which occurs in the chemical plant must feedback to the nuclear reactor. There are many different types of accidents which can occur in a chemical plant. These accidents include intra-reactor piping failure, inter-reactor piping failure, reaction chamber failure and heat exchanger failure. Since the chemical plant acts as the heat sink for the nuclear reactor, any of these accidents induce a loss-of-heat-sink accident in the nuclear reactor. In this paper, several chemical plant initiated accident scenarios are presented. The following accident scenarios are proposed: i) failure of the Bunsen chemical reactor; ii) product flow failure from either the H 2 SO 4 decomposition section or HI decomposition section; iii) reactant flow failure from either the H 2 SO 4 decomposition section or HI decomposition section; iv) rupture of a reaction chamber. Qualitative analysis of these accident scenarios indicates that each result in either partial or total loss of heat sink accidents for the nuclear reactor. These scenarios are reduced to two types: i) discharge rate limited accidents; ii) discontinuous reaction chamber accidents. A discharge rate limited rupture of the SO 3 decomposition section of the SI cycle is proposed and modelled. Since SO 3 decomposition occurs in the gaseous phase, critical flow out of the rupture is calculated assuming ideal gas behaviour. The accident scenario is modelled using a fully transient control volume model of the S-I cycle coupled to a THERMIX model of a 268 MW pebble bed modular reactor (PBMR-268) and a point kinetics model. The Bird, Stewart and Lightfoot source model for choked gas flows from a pressurised chamber was utilised as a discharge rate model. A discharge coefficient of 0.62 was assumed. Feedback due to the rupture is observed in the nuclear

Sampling the stratum corneum for toxic chemicals.

Science.gov (United States)

Coman, Garrett; Blickenstaff, Nicholas R; Blattner, Collin M; Andersen, Rosa; Maibach, Howard I

2014-01-01

Dermal exposure is an important pathway in environmental health. Exposure comes from contaminated water, soil, treated surfaces, textiles, aerosolized chemicals, and agricultural products. It can occur in homes, schools, play areas, and work settings in the form of industrial sources, consumer products, or hazardous wastes. Dermal exposure is most likely to occur through contact with liquids, water, soil, sediment, and contaminated surfaces. The ability to detect and measure exposure to toxic materials on the skin is an important environmental health issue. The stratum corneum is the skin's first and principal barrier layer of protection from the outside world. It has a complex structure that can effectively protect against a wide variety of physical, chemical, and biological contaminants. However, there are a variety of chemical agents that can damage the stratum corneum and the underlying epidermis, dermis and subcutis, and/or enter systemic circulation through the skin. There are numerous ways of sampling the stratum corneum for these toxic materials like abrasion techniques, biopsy, suction blistering, imaging, washing, wipe sampling, tape stripping, and spot testing. Selecting a method likely depends on the particular needs of the situation. Hence, there is a need to review practical considerations for their use in sampling the stratum corneum for toxins.

Exploring the role of quantum chemical descriptors in modeling acute toxicity of diverse chemicals to Daphnia magna.

Science.gov (United States)

Reenu; Vikas

2015-09-01

Various quantum-mechanically computed molecular and thermodynamic descriptors along with physico-chemical, electrostatic and topological descriptors are compared while developing quantitative structure-activity relationships (QSARs) for the acute toxicity of 252 diverse organic chemicals towards Daphnia magna. QSAR models based on the quantum-chemical descriptors, computed with routinely employed advanced semi-empirical and ab-initio methods, along with the electron-correlation contribution (CORR) of the descriptors, are analyzed for the external predictivity of the acute toxicity. The models with reliable internal stability and external predictivity are found to be based on the HOMO energy along with the physico-chemical, electrostatic and topological descriptors. Besides this, the total energy and electron-correlation energy are also observed as highly reliable descriptors, suggesting that the intra-molecular interactions between the electrons play an important role in the origin of the acute toxicity, which is in fact an unexplored phenomenon. The models based on quantum-chemical descriptors such as chemical hardness, absolute electronegativity, standard Gibbs free energy and enthalpy are also observed to be reliable. A comparison of the robust models based on the quantum-chemical descriptors computed with various quantum-mechanical methods suggests that the advanced semi-empirical methods such as PM7 can be more reliable than the ab-initio methods which are computationally more expensive. Copyright © 2015 Elsevier Inc. All rights reserved.

Toxicity assessment of chemical contaminants;transition from in vitromethods to novel in vitro methods

Directory of Open Access Journals (Sweden)

A.A. Farshad

2007-04-01

Full Text Available Exposure to occupational and environmental contaminants is a major contributor to human health problems. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there areapproximately 80, 000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from ethical, economical and scientific perspectives. Therefore, increasing the number of available industrial chemicals andnew products has created a demand for alternatives to animal methods for better safety evaluation. Recent toxicity studies have demonstrated that in vitro methods are capable of rapidly providing toxicity information. In this review, current toxicity test methods for risk evaluation of industrial chemical contaminants are presented. To evaluate the potential applications of  more recent test methods developed for toxicity testing of chemical contaminants are discussed. Although  to be considered more broadly for risk assessment of human chemical exposures. In vitro methods,in vitro toxicology methods cannot exactly mimic the biodynamics of the whole body, in vitro  relationships (QSARs and physiologically based toxicokinetic (PBTK models have a potentialtest systems in combination with the knowledge of quantitative structure activity.

Systematic approach for assessment of accident risks in chemical and nuclear processing

International Nuclear Information System (INIS)

Senne Junior, Murillo

2003-07-01

The industrial accidents which occurred in the last years, particularly in the 80's, contributed a significant way to draw the attention of the government, industry and the society as a whole to the mechanisms for preventing events that could affect people's safety and the environment quality. Techniques and methods extensively used the nuclear, aeronautic and war industries so far were adapted to performing analysis and evaluation of the risks associated to other industrial activities, especially in the petroleum, chemistry and petrochemical areas. The risk analysis in industrial facilities is carried out through the evaluation of the probability or frequency of the accidents and their consequences. However, no systematized methodology that could supply the tools for identifying possible accidents likely to take place in an installation is available in the literature. Neither existing are methodologies for the identification of the models for evaluation of the accidents' consequences nor for the selection of the available techniques for qualitative or quantitative analysis of the possibility of occurrence of the accident being focused. The objective of this work is to develop and implement a methodology for identification of the risks of accidents in chemical and nuclear processing facilities as well as for the evaluation of their consequences on persons. For the development of the methodology, the main possible accidents that could occur in such installations were identified and the qualitative and quantitative techniques available for the identification of the risks and for the evaluation of the consequences of each identified accidents were selected. The use of the methodology was illustrated by applying it in two case examples adapted from the literature, involving accidents with inflammable, explosives, and radioactive materials. The computer code MRA - Methodology for Risk Assessment was developed using DELPHI, version 5.0, with the purpose of systematizing

Interactions between toxic chemicals and natural environmental factors--a meta-analysis and case studies.

Science.gov (United States)

Laskowski, Ryszard; Bednarska, Agnieszka J; Kramarz, Paulina E; Loureiro, Susana; Scheil, Volker; Kudłek, Joanna; Holmstrup, Martin

2010-08-15

The paper addresses problems arising from effects of natural environmental factors on toxicity of pollutants to organisms. Most studies on interactions between toxicants and natural factors, including those completed in the EU project NoMiracle (Novel Methods for Integrated Risk Assessment of Cumulative Stressors in Europe) described herein, showed that effects of toxic chemicals on organisms can differ vastly depending purely on external conditions. We compiled data from 61 studies on effects of temperature, moisture and dissolved oxygen on toxicity of a range of chemicals representing pesticides, polycyclic aromatic hydrocarbons, plant protection products of bacterial origin and trace metals. In 62.3% cases significant interactions (pnatural factors and chemicals were found, reaching 100% for the effect of dissolved oxygen on toxicity of waterborne chemicals. The meta-analysis of the 61 studies showed that the null hypothesis assuming no interactions between toxic chemicals and natural environmental factors should be rejected at p=2.7 x 10(-82) (truncated product method probability). In a few cases of more complex experimental designs, also second-order interactions were found, indicating that natural factors can modify interactions among chemicals. Such data emphasize the necessity of including information on natural factors and their variation in time and across geographic regions in ecological risk assessment. This can be done only if appropriate ecotoxicological test designs are used, in which test organisms are exposed to toxicants at a range of environmental conditions. We advocate designing such tests for the second-tier ecological risk assessment procedures. Copyright 2010 Elsevier B.V. All rights reserved.

The chemical toxicity of cesium in Indian mustard (Brassica juncea L.) seedlings

International Nuclear Information System (INIS)

Lai, Jin-long; Tao, Zong-ya; Fu, Qian; Han, Na; Wu, Guo; Zhang, Hong; Lu, Hong; Luo, Xue-gang

2016-01-01

To distinguish between the radiological and chemical effects of radiocesium, we study the chemical toxicity of cesium in the seedlings of Indian mustard (Brassica juncea L.). In this study, the experiment was designed in two factors and five levels random block design to investigate the interaction effects of Cs and K. Results showed that excessive Cs was one of the main factors influence the growth of Brassica juncea seedlings. And the toxicity of Cs in Brassica juncea is likely to be caused by Cs interacts with K-binding sites in essential K-dependent protein, either competes with K for essential biochemical functions, causing intracellular metabolic disturbance. To test the hypothesis that the toxicity of Cs might cause intracellular metabolic disturbance, next-generation sequencing (NGS)-based Illumina paired-end Solexa sequencing platform was employed to analysis the changes in gene expression, and understand the key genes in B. juncea seedlings responding to the toxicity of Cs. Based on the assembled de novo transcriptome, 2032 DEGs that play significant roles in the response to the toxicity of Cs were identified. Further analysis showed that excessive Cs is disturbance the auxin signal transduction pathway, and inhibited the indoleacetic acid-induced protein (AUX/IAA) genes expression eventually lead the seedlings growth and development be inhibited. The results suggest that disturbances to tryptophan metabolism might be linked to changes in growth. - Highlights: • Analyze the chemical toxicity of cesium in seedlings of Indian mustard. • Distinguish between the radiological and chemical effects of radiocesium. • 2032 DEGs that play significant roles in the response to Cs toxicity were identified. • Excessive Cs is disturbance the auxin signal transduction pathway.

In silico prediction of toxicity of non-congeneric industrial chemicals using ensemble learning based modeling approaches

Energy Technology Data Exchange (ETDEWEB)

Singh, Kunwar P., E-mail: kpsingh_52@yahoo.com; Gupta, Shikha

2014-03-15

Ensemble learning approach based decision treeboost (DTB) and decision tree forest (DTF) models are introduced in order to establish quantitative structure–toxicity relationship (QSTR) for the prediction of toxicity of 1450 diverse chemicals. Eight non-quantum mechanical molecular descriptors were derived. Structural diversity of the chemicals was evaluated using Tanimoto similarity index. Stochastic gradient boosting and bagging algorithms supplemented DTB and DTF models were constructed for classification and function optimization problems using the toxicity end-point in T. pyriformis. Special attention was drawn to prediction ability and robustness of the models, investigated both in external and 10-fold cross validation processes. In complete data, optimal DTB and DTF models rendered accuracies of 98.90%, 98.83% in two-category and 98.14%, 98.14% in four-category toxicity classifications. Both the models further yielded classification accuracies of 100% in external toxicity data of T. pyriformis. The constructed regression models (DTB and DTF) using five descriptors yielded correlation coefficients (R{sup 2}) of 0.945, 0.944 between the measured and predicted toxicities with mean squared errors (MSEs) of 0.059, and 0.064 in complete T. pyriformis data. The T. pyriformis regression models (DTB and DTF) applied to the external toxicity data sets yielded R{sup 2} and MSE values of 0.637, 0.655; 0.534, 0.507 (marine bacteria) and 0.741, 0.691; 0.155, 0.173 (algae). The results suggest for wide applicability of the inter-species models in predicting toxicity of new chemicals for regulatory purposes. These approaches provide useful strategy and robust tools in the screening of ecotoxicological risk or environmental hazard potential of chemicals. - Graphical abstract: Importance of input variables in DTB and DTF classification models for (a) two-category, and (b) four-category toxicity intervals in T. pyriformis data. Generalization and predictive abilities of the

In silico prediction of toxicity of non-congeneric industrial chemicals using ensemble learning based modeling approaches

International Nuclear Information System (INIS)

Singh, Kunwar P.; Gupta, Shikha

2014-01-01

Ensemble learning approach based decision treeboost (DTB) and decision tree forest (DTF) models are introduced in order to establish quantitative structure–toxicity relationship (QSTR) for the prediction of toxicity of 1450 diverse chemicals. Eight non-quantum mechanical molecular descriptors were derived. Structural diversity of the chemicals was evaluated using Tanimoto similarity index. Stochastic gradient boosting and bagging algorithms supplemented DTB and DTF models were constructed for classification and function optimization problems using the toxicity end-point in T. pyriformis. Special attention was drawn to prediction ability and robustness of the models, investigated both in external and 10-fold cross validation processes. In complete data, optimal DTB and DTF models rendered accuracies of 98.90%, 98.83% in two-category and 98.14%, 98.14% in four-category toxicity classifications. Both the models further yielded classification accuracies of 100% in external toxicity data of T. pyriformis. The constructed regression models (DTB and DTF) using five descriptors yielded correlation coefficients (R 2 ) of 0.945, 0.944 between the measured and predicted toxicities with mean squared errors (MSEs) of 0.059, and 0.064 in complete T. pyriformis data. The T. pyriformis regression models (DTB and DTF) applied to the external toxicity data sets yielded R 2 and MSE values of 0.637, 0.655; 0.534, 0.507 (marine bacteria) and 0.741, 0.691; 0.155, 0.173 (algae). The results suggest for wide applicability of the inter-species models in predicting toxicity of new chemicals for regulatory purposes. These approaches provide useful strategy and robust tools in the screening of ecotoxicological risk or environmental hazard potential of chemicals. - Graphical abstract: Importance of input variables in DTB and DTF classification models for (a) two-category, and (b) four-category toxicity intervals in T. pyriformis data. Generalization and predictive abilities of the

Effects of toxic metals and chemicals on biofilm and biocorrosion.

Science.gov (United States)

Fang, Herbert H P; Xu, Li-Chong; Chan, Kwong-Yu

2002-11-01

Microbes in marine biofilms aggregated into clusters and increased the production of extracellular polymeric substances (EPS), by over 100% in some cases, when the seawater media containing toxic metals and chemicals, such as Cd(II), Cu(II), Pb(II), Zn(II), AI(III), Cr(III), glutaraldehyde, and phenol. The formation of microbial cluster and the increased production of EPS, which contained 84-92% proteins and 8-16% polysaccharides, accelerated the corrosion of the mild steel. However, there was no quantitative relationship between the degree of increased corrosion and the toxicity of metals/chemicals towards sulfate-reducing bacteria, or the increased EPS production.

Drivers of accident preparedness and safety: evidence from the RMP Rule

International Nuclear Information System (INIS)

Kleindorfer, Paul R.; Elliott, Michael R.; Wang Yanlin; Lowe, Robert A.

2004-01-01

This paper provides an overview of recent results derived from the accident history data collected under 112(r) of the Clean Air Act Amendments (the Risk Management Program (RMP) Rule) covering the period 1994-2000, together with a preliminary assessment of the effectiveness of the RMP Rule as a form of Management System Regulation. These were undertaken at the University of Pennsylvania by a multi-disciplinary team of economists, statisticians and epidemiologists with the support of the US Environmental Protection Agency and its Office of Emergency Prevention, Preparedness and Response (OEPPR, formerly CEPPO). Section 112(r) of the Clean Air Act Amendments of 1990 requires that chemical facilities in the US that had on premises more than specified quantities of toxic or flammable chemicals file a 5-year history of accidents. The initial data reported under the RMP Rule covered roughly the period from mid-1994 through mid-2000, and provided details on economic, environmental and acute health affects resulting from accidents at some 15,000 US chemical facilities for this period. This paper reviews research based on this data. The research is in the form of a retrospective cohort study that considers the statistical associations between accident frequency and accident severity at covered facilities (the outcome variables of interest) and a number of facility characteristics (the available predictor variables provided by the RMP Rule), the latter including such facility characteristics as size, hazardousness, financial characteristics of parent company-owners of the facility, regulatory programs in force at the facility, and host community characteristics for the surrounding county in which the facility was located, as captured in the 1990 Census. Among the findings reviewed are: (1) positive associations with (a measure of) facility hazardousness and accident, injury and economic costs of accidents; (2) positive (resp., negative) associations between accident

Acute toxicity of fire-retardant and foam-suppressant chemicals to yalella azteca (Saussure)

Science.gov (United States)

McDonald, Susan F.; Hamilton, Steven J.; Buhl, Kevin J.; Heisinger, James F.

1997-01-01

Acute toxicity tests were conducted with Hyalella azteca Saussure (an amphipod) exposed in soft and hard waters to three fire retardants (Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F) and two foam suppressants (Phos-Chek WD-881 and Silv-Ex). The chemicals were slightly to moderately toxic to amphipods. The most toxic chemical to amphipods in soft and hard water was Phos-Chek WD-881 (96-h mean lethal concentration [LC50] equal to 10 mg/L and 22 mg/L, respectively), and the least toxic chemical to amphipods in soft water was Fire-Trol GTS-R (96-h LC50 equal to 127 mg/L) and in hard water was Fire-Trol LCG-R (96-h LC50 equal to 535 mg/L). Concentrations of ammonia in tests with the three fire retardants and both water types were greater than reported LC50 values and probably were the major toxic component. Estimated un-ionized ammonia concentrations near the LC50 were frequently less than the reported LC50 ammonia concentrations for amphipods. The three fire retardants were more toxic in soft water than in hard water even though ammonia and un-ionized ammonia concentrations were higher in hard water tests than in soft water tests. The accidental entry of fire-fighting chemicals into aquatic environments could adversely affect aquatic invertebrates, thereby disrupting ecosystem function.

Dissecting the assays to assess microbial tolerance to toxic chemicals in bioprocessing.

Science.gov (United States)

Zingaro, Kyle A; Nicolaou, Sergios A; Papoutsakis, Eleftherios T

2013-11-01

Microbial strains are increasingly used for the industrial production of chemicals and biofuels, but the toxicity of components in the feedstock and product streams limits process outputs. Selected or engineered microbes that thrive in the presence of toxic chemicals can be assessed using tolerance assays. Such assays must reasonably represent the conditions the cells will experience during the intended process and measure the appropriate physiological trait for the desired application. We review currently used tolerance assays, and examine the many parameters that affect assay outcomes. We identify and suggest the use of the best-suited assays for each industrial bioreactor operating condition, discuss next-generation assays, and propose a standardized approach for using assays to examine tolerance to toxic chemicals. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fate of chemical warfare agents and toxic indutrial chemicals in landfills

DEFF Research Database (Denmark)

Bartelt-Hunt, D.L.; Barlaz, M.A.; Knappe, D.R.U.

2006-01-01

One component of preparedness for a chemical attack is planning for the disposal of contaminated debris. To assess the feasibility of contaminated debris disposal in municipal solid waste (MSW) landfills, the fate of selected chemical warfare agents (CWAs) and toxic industrial chemicals (TICs......], and two TICs [furan and carbon disulfide] were studied. The effects of both infiltration (climate) and contaminant biodegradability on fate predictions were assessed. Model results showed that hydrolysis and gas-phase advection were the principal fate pathways for CWAs and TICs, respectively. Apart from...... CX and the TICs, none of the investigated compounds was predicted to persist in a landfill for more than 5 years. Climate had little impact on CWA/TIC fate, and biodegradability was only important for compounds with long hydrolysis halflives. Monte Carlo simulations were performed to assess...

Toxicity of organic chemical pollution in groundwater downgradient of a landfill (Grindsted, Denmark)

DEFF Research Database (Denmark)

Baun, Anders; Jensen, S. D.; Bjerg, Poul Løgstrup

2000-01-01

The aim of the present study was to describe the occurrence and distribution of toxicity related to organic chemical contaminants in the leachate plume downgradient of the Grindsted Landfill (Denmark). A total of 27 groundwater samples were preconcentrated by solidphase extraction (SPE) using XAD-2...... bioassays, it was concluded that SPE extracts of groundwater collected close to the landfill were toxic. The toxicity decreased with the distance from the landfill. At distances greater than 80 m from the border of the landfill, the groundwater toxicity was not significantly different from the background...... characterization and hazard ranking of groundwater polluted with complex chemical mixtures, such as landfill leachates....

Use of questionnaires and an expert panel to judge the environmental consequences of chemical spills for the development of an environment-accident index.

Science.gov (United States)

Andersson, Asa Scott; Stjernström, Olof; Fängmark, Ingrid

2005-05-01

Assessing the environmental consequences of a chemical accident is a complex task. To date, the methods used to evaluate the environmental effects of an acute release of a chemical have often been based on measurements of chemical and physical variables deemed to be important, such as the concentration of the chemical. However, a broader strategy is needed to predict the environmental consequences of potential accidents during the planning process. An Environment-Accident Index (EAI), a simple tool based on such a strategy, has been developed to facilitate the consideration of a multitude of influential variables. The objectives of this study were to evaluate whether questionnaire-based expert panel's judgements could provide useful data on the environmental consequences of chemical spills, and an effective basis for further development of the EAI. As expected, the judgements did not agree perfectly, but they do give rough indications of the environmental effects, and highlight consistent trends that should be useful inputs for planning, prevention and decontamination processes. The different accidents were also judged to have caused everything from minor to very major effects in the environment, implying that a wide range of accident scenarios were represented in the material and covered by the EAI. Therefore, questionnaires and expert panel judgements can be used to collect useful data for estimating the likely environmental consequences of chemical accidents and for further development of the EAI.

In silico assessment of the acute toxicity of chemicals: recent advances and new model for multitasking prediction of toxic effect.

Science.gov (United States)

Kleandrova, Valeria V; Luan, Feng; Speck-Planche, Alejandro; Cordeiro, M Natália D S

2015-01-01

The assessment of acute toxicity is one of the most important stages to ensure the safety of chemicals with potential applications in pharmaceutical sciences, biomedical research, or any other industrial branch. A huge and indiscriminate number of toxicity assays have been carried out on laboratory animals. In this sense, computational approaches involving models based on quantitative-structure activity/toxicity relationships (QSAR/QSTR) can help to rationalize time and financial costs. Here, we discuss the most significant advances in the last 6 years focused on the use of QSAR/QSTR models to predict acute toxicity of drugs/chemicals in laboratory animals, employing large and heterogeneous datasets. The advantages and drawbacks of the different QSAR/QSTR models are analyzed. As a contribution to the field, we introduce the first multitasking (mtk) QSTR model for simultaneous prediction of acute toxicity of compounds by considering different routes of administration, diverse breeds of laboratory animals, and the reliability of the experimental conditions. The mtk-QSTR model was based on artificial neural networks (ANN), allowing the classification of compounds as toxic or non-toxic. This model correctly classified more than 94% of the 1646 cases present in the whole dataset, and its applicability was demonstrated by performing predictions of different chemicals such as drugs, dietary supplements, and molecules which could serve as nanocarriers for drug delivery. The predictions given by the mtk-QSTR model are in very good agreement with the experimental results.

An Acetyltransferase Conferring Tolerance to Toxic Aromatic Amine Chemicals

Science.gov (United States)

Martins, Marta; Rodrigues-Lima, Fernando; Dairou, Julien; Lamouri, Aazdine; Malagnac, Fabienne; Silar, Philippe; Dupret, Jean-Marie

2009-01-01

Aromatic amines (AA) are a major class of environmental pollutants that have been shown to have genotoxic and cytotoxic potentials toward most living organisms. Fungi are able to tolerate a diverse range of chemical compounds including certain AA and have long been used as models to understand general biological processes. Deciphering the mechanisms underlying this tolerance may improve our understanding of the adaptation of organisms to stressful environments and pave the way for novel pharmaceutical and/or biotechnological applications. We have identified and characterized two arylamine N-acetyltransferase (NAT) enzymes (PaNAT1 and PaNAT2) from the model fungus Podospora anserina that acetylate a wide range of AA. Targeted gene disruption experiments revealed that PaNAT2 was required for the growth and survival of the fungus in the presence of toxic AA. Functional studies using the knock-out strains and chemically acetylated AA indicated that tolerance of P. anserina to toxic AA was due to the N-acetylation of these chemicals by PaNAT2. Moreover, we provide proof-of-concept remediation experiments where P. anserina, through its PaNAT2 enzyme, is able to detoxify the highly toxic pesticide residue 3,4-dichloroaniline in experimentally contaminated soil samples. Overall, our data show that a single xenobiotic-metabolizing enzyme can mediate tolerance to a major class of pollutants in a eukaryotic species. These findings expand the understanding of the role of xenobiotic-metabolizing enzyme and in particular of NATs in the adaptation of organisms to their chemical environment and provide a basis for new systems for the bioremediation of contaminated soils. PMID:19416981

THE DETERMINATION AND APPRECIATION OF OCCUPATIONAL TOXICITY AT WORK

Directory of Open Access Journals (Sweden)

Oana CHIVU

2017-05-01

Full Text Available The occupational toxins are those chemicals that workers come into contact with during the exercise of the profession and which under certain conditions have harmful effects on the body. The paper aims to address the determination and assessment of occupational toxicities in a workplace with the aim of ensuring an adequate working enviro nment as well as preventing occupational diseases, accidents and chronic fatigue.

THE DETERMINATION AND APPRECIATION OF OCCUPATIONAL TOXICITY AT WORK

OpenAIRE

Oana CHIVU; Claudiu BABIS; Andrei DIMITRESCU

2017-01-01

The occupational toxins are those chemicals that workers come into contact with during the exercise of the profession and which under certain conditions have harmful effects on the body. The paper aims to address the determination and assessment of occupational toxicities in a workplace with the aim of ensuring an adequate working enviro nment as well as preventing occupational diseases, accidents and chronic fatigue.

Assessment of chemical processes for the post-accident decontamination of reactor-coolant systems. Final report

International Nuclear Information System (INIS)

Munson, L.F.; Card, C.J.; Divine, J.R.

1983-02-01

Previously used chemical decontamination processes and potentially useful new decontamination processes were examined for the usefulness following a reactor accident. Both generic fuel damage accidents and the accident at TMI-2 were considered. A total of fourteen processes were evaluated. Process evaluation included data in the following categories: technical description of the process, recorded past usage, effectiveness, process limitation, safety consideration, and waste management. These data were evaluated, and cost considerations were presented along with a description of the applicability of the process to TMI-2 and development and demonstration needs. Specific recommendations regarding a primary-system decontamination development program to support TMI-2 recovery were also presented

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

Science.gov (United States)

2013-11-19

...; Acute emulsion polymerization in Inhalation Toxicity in paper, textile, fiber, and Rats; Bacterial.../ Reproduction Development Toxicity. Note: CAS No. = Chemical Abstracts Service Registry Number. Authority: 15 U...

Biomass accident investigations – missed opportunities for learning and accident prevention

DEFF Research Database (Denmark)

Hedlund, Frank Huess

2017-01-01

The past decade has seen a major increase in the production of energy from biomass. The growth has been mirrored in an increase of serious biomass related accidents involving fires, gas explosions, combustible dust explosions and the release of toxic gasses. There are indications that the number...... of bioenergy related accidents is growing faster than the energy production. This paper argues that biomass accidents, if properly investigated and lessons shared widely, provide ample opportunities for improving general hazard awareness and safety performance of the biomass industry. The paper examines...... selected serious accidents involving biogas and wood pellets in Denmark and argues that such opportunities for learning were missed because accident investigations were superficial, follow-up incomplete and information sharing absent. In one particularly distressing case, a facility saw a repeat accident...

Plant exposure chambers for study of toxic chemical-plant interactions (journal version)

International Nuclear Information System (INIS)

McFarlane, J.C.; Pfleeger, T.

1987-01-01

Chambers for the study of plant uptake and phytotoxicity of toxic, radio-labeled chemicals are described. The chambers are designed to meet the criteria of continuously stirred tank reactors while providing containment for toxic chemicals. They are computer managed and operated within a controlled-environment room. Besides providing controlled conditions within the contained spaces, continuous measurements are made of various environmental parameters and plant transpiration, net photosynthesis, and dark respiration in up to 18 separate chambers

Cobalt toxicity: Chemical and radiological combined effects on HaCaT keratinocyte cell line

International Nuclear Information System (INIS)

Sandre, C.; Moulin, C.; Bresson, C.; Gault, N.; Poncy, J. L.; Lefaix, J. L.

2010-01-01

Cobalt (Co) is an essential trace element well known as a constituent of vitamin B 12 , but different compounds of Co are also described as highly toxic and/or radio-toxic for individuals or the environment. In nuclear power plants, 58 Co and 60 Co are radioactive isotopes of cobalt present as activation products of stable Co and Ni used in alloys. Skin exposure is a current occupational risk in the hard metal and nuclear industries. As biochemical and molecular cobalt-induced toxicological mechanisms are not fully identified, we investigated cobalt toxicity in a model human keratinocyte cell line, HaCaT. In this study, we propose a model to determine the in vitro chemical impact on cell viability of a soluble form of cobalt (CoCl 2 ) with or without gamma-ray doses to mimic contamination by 60 Co, to elucidate the mechanisms of cobalt intracellular chemical and radiological toxicity. Intracellular cobalt concentration was determined after HaCaT cell contamination and chemical toxicity was evaluated in terms of cellular viability and clonogenic survival. We investigated damage to DNA in HaCaT cells by combined treatment with chemical cobalt and a moderate gamma-ray dose. Additive effects of cobalt and irradiation were demonstrated. The underlying mechanism of cobalt toxicity is not clearly established, but our results seem to indicate that the toxicity of Co(II) and of irradiation arises from production of reactive oxygen species. (authors)

Cobalt toxicity: Chemical and radiological combined effects on HaCaT keratinocyte cell line

Energy Technology Data Exchange (ETDEWEB)

Gault, N. [CEA Fontenay aux Roses, DSV/IRCM/SCSR/LRTS, 92265 Fontenay aux Rose (France); Sandre, C.; Moulin, B.; Bresson, C. [CEA, DEN, SECR, Laboratoire de Speciation des Radionucleides et des Molecules, F-91191 Gif-sur-Yvette (France); Poncy, J.L. [CEA Bruyeres Le Chatel, DSV/IRCM/SREIT/LRT, 91680 Bruyeres Le Chatel (France); Lefaix, J.L. [CEA Caen, DSV/IRCM/SRO/LARIA, 14070 Caen (France)

2010-07-01

Cobalt (Co) is an essential trace element well known as a constituent of vitamin B12, but different compounds of Co are also described as highly toxic and/or radio-toxic for individuals or the environment. In nuclear power plants, {sup 58}Co and {sup 60}Co are radioactive isotopes of cobalt present as activation products of stable Co and Ni used in alloys. Skin exposure is a current occupational risk in the hard metal and nuclear industries. As biochemical and molecular cobalt-induced toxicological mechanisms are not fully identified, we investigated cobalt toxicity in a model human keratinocyte cell line, HaCaT. In this study, we propose a model to determine the in vitro chemical impact on cell viability of a soluble form of cobalt (CoCl{sub 2}) with or without {gamma}-ray doses to mimic contamination by {sup 60}Co, to elucidate the mechanisms of cobalt intracellular chemical and radiological toxicity. Intracellular cobalt concentration was determined after HaCaT cell contamination and chemical toxicity was evaluated in terms of cellular viability and clonogenic survival. We investigated damage to DNA in HaCaT cells by combined treatment with chemical cobalt and a moderate {gamma}-ray dose. Additive effects of cobalt and irradiation were demonstrated. The underlying mechanism of cobalt toxicity is not clearly established, but our results seem to indicate that the toxicity of Co(II) and of irradiation arises from production of reactive oxygen species. (authors)

Cobalt toxicity: Chemical and radiological combined effects on HaCaT keratinocyte cell line

Energy Technology Data Exchange (ETDEWEB)

Sandre, C.; Moulin, C.; Bresson, C. [CEA Saclay, DEN, SECR, Lab Speciat Radionucleides and Mol, F-91191 Gif Sur Yvette (France); Gault, N. [CEA Fontenay Roses, DSV IRCM SCSR LRTS, F-92265 Fontenay Aux Roses (France); Poncy, J. L. [CEA Bruyeres Le Chatel, DSV IRCM SREIT LRT, F-91680 Bruyeres Le Chatel (France); Lefaix, J. L. [CEA Caen, DSV IRCM SRO LARIA, F-14070 Caen (France)

2010-07-01

Cobalt (Co) is an essential trace element well known as a constituent of vitamin B{sub 12}, but different compounds of Co are also described as highly toxic and/or radio-toxic for individuals or the environment. In nuclear power plants, {sup 58}Co and {sup 60}Co are radioactive isotopes of cobalt present as activation products of stable Co and Ni used in alloys. Skin exposure is a current occupational risk in the hard metal and nuclear industries. As biochemical and molecular cobalt-induced toxicological mechanisms are not fully identified, we investigated cobalt toxicity in a model human keratinocyte cell line, HaCaT. In this study, we propose a model to determine the in vitro chemical impact on cell viability of a soluble form of cobalt (CoCl{sub 2}) with or without gamma-ray doses to mimic contamination by {sup 60}Co, to elucidate the mechanisms of cobalt intracellular chemical and radiological toxicity. Intracellular cobalt concentration was determined after HaCaT cell contamination and chemical toxicity was evaluated in terms of cellular viability and clonogenic survival. We investigated damage to DNA in HaCaT cells by combined treatment with chemical cobalt and a moderate gamma-ray dose. Additive effects of cobalt and irradiation were demonstrated. The underlying mechanism of cobalt toxicity is not clearly established, but our results seem to indicate that the toxicity of Co(II) and of irradiation arises from production of reactive oxygen species. (authors)

Elucidating mechanisms of toxic action of dissolved organic chemicals in oil sands process-affected water (OSPW).

Science.gov (United States)

Morandi, Garrett D; Wiseman, Steve B; Guan, Miao; Zhang, Xiaowei W; Martin, Jonathan W; Giesy, John P

2017-11-01

Oil sands process-affected water (OSPW) is generated during extraction of bitumen in the surface-mining oil sands industry in Alberta, Canada, and is acutely and chronically toxic to aquatic organisms. It is known that dissolved organic compounds in OSPW are responsible for most toxic effects, but knowledge of the specific mechanism(s) of toxicity, is limited. Using bioassay-based effects-directed analysis, the dissolved organic fraction of OSPW has previously been fractionated, ultimately producing refined samples of dissolved organic chemicals in OSPW, each with distinct chemical profiles. Using the Escherichia coli K-12 strain MG1655 gene reporter live cell array, the present study investigated relationships between toxic potencies of each fraction, expression of genes and characterization of chemicals in each of five acutely toxic and one non-toxic extract of OSPW derived by use of effects-directed analysis. Effects on expressions of genes related to response to oxidative stress, protein stress and DNA damage were indicative of exposure to acutely toxic extracts of OSPW. Additionally, six genes were uniquely responsive to acutely toxic extracts of OSPW. Evidence presented supports a role for sulphur- and nitrogen-containing chemical classes in the toxicity of extracts of OSPW. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemical toxicity and radiological health detriment associated with the inhalation of various enrichments of uranium

International Nuclear Information System (INIS)

3C Limited, Queen Square House, 18-21 Queen Square, Bristol BS1 4NH (United Kingdom))" data-affiliation=" (SR3C Limited, Queen Square House, 18-21 Queen Square, Bristol BS1 4NH (United Kingdom))" >Bryant, P A

2014-01-01

The occupational risks associated with the chemical toxicity of uranium can be overlooked during the processing, handling and storage of the material, as the radioactivity of the material is often used alone to assess the health consequences of exposure to uranium compounds. This note provides a summary of the current United Kingdom occupational standards for uranium based on radiation dose and/or chemical toxicity with a particular focus on intake via inhalation. A simple model is subsequently presented to allow a comparison to be drawn between the occupational exposure standard for chemical toxicity and radiological dose limit. Using these data a set of suggested limits on occupational exposure to airborne uranium is proposed that indicate where the legal annual radiological dose limit for workers or the Health and Safety Executive occupational exposure standard for chemical toxicity are at risk of being breached. (note)

Acclimation of Chlamydomonas reinhardtii to ultraviolet radiation and its impact on chemical toxicity

Energy Technology Data Exchange (ETDEWEB)

Korkaric, Muris; Xiao, Mao [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600 Duebendorf (Switzerland); ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics, 8092 Zürich (Switzerland); Behra, Renata [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600 Duebendorf (Switzerland); Eggen, Rik I.L., E-mail: rik.eggen@eawag.ch [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600 Duebendorf (Switzerland); ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics, 8092 Zürich (Switzerland)

2015-10-15

Highlights: • Systematic study of UVR acclimation and its impact on chemical toxicity in C. reinhardtii. • UVR acclimation is mediated through fast and reversible physiological defense mechanisms. • Pigment analysis suggests a role of lutein in UVR acclimation. • Co-tolerance to rose bengal suggests a role of singlet oxygen defense in UVR acclimation. • Knowledge on the toxic mechanism of chemicals needed to predict co-tolerance. - Abstract: The toxicity of chemical pollutants can be modulated under stressful environmental conditions, such as increased temperature, salinity or ultraviolet radiation (UVR), due to the interaction of effects during simultaneous stressor exposure. However, organisms may acclimate to such conditions by activation of physiological and biochemical defence mechanisms. In sequential exposures, organisms acclimated to environmental stressors may display an increased sensitivity or co-tolerance towards chemical pollutants. It has been suggested that co-tolerance might be expected for similarly acting stressors due to common defence mechanisms. To test this for combinations of UVR and chemical stressors, we first acclimatized the model green alga Chlamydomonas reinhardtii to UVR and subsequently compared the sensitivity of UVR pre-exposed and control algae towards chemicals. Selected chemicals all act on photosynthesis and thus share a common physiological target, but display distinct toxicity mechanisms. Results showed that UVR pre-exposure for four days partially inhibited algal growth and photosynthesis, but also increased algal tolerance to higher UVR levels, confirming UVR acclimation. HPLC analysis of algal pigments indicated that UVR acclimation might in part be explained by the protective function of lutein while the contribution of UVR absorbing compounds was less clear. Challenge exposure to chemicals in the absence of UVR showed that acclimated algae were co-tolerant to the photosensitizer rose bengal, but not to the

Acclimation of Chlamydomonas reinhardtii to ultraviolet radiation and its impact on chemical toxicity

International Nuclear Information System (INIS)

Korkaric, Muris; Xiao, Mao; Behra, Renata; Eggen, Rik I.L.

2015-01-01

Highlights: • Systematic study of UVR acclimation and its impact on chemical toxicity in C. reinhardtii. • UVR acclimation is mediated through fast and reversible physiological defense mechanisms. • Pigment analysis suggests a role of lutein in UVR acclimation. • Co-tolerance to rose bengal suggests a role of singlet oxygen defense in UVR acclimation. • Knowledge on the toxic mechanism of chemicals needed to predict co-tolerance. - Abstract: The toxicity of chemical pollutants can be modulated under stressful environmental conditions, such as increased temperature, salinity or ultraviolet radiation (UVR), due to the interaction of effects during simultaneous stressor exposure. However, organisms may acclimate to such conditions by activation of physiological and biochemical defence mechanisms. In sequential exposures, organisms acclimated to environmental stressors may display an increased sensitivity or co-tolerance towards chemical pollutants. It has been suggested that co-tolerance might be expected for similarly acting stressors due to common defence mechanisms. To test this for combinations of UVR and chemical stressors, we first acclimatized the model green alga Chlamydomonas reinhardtii to UVR and subsequently compared the sensitivity of UVR pre-exposed and control algae towards chemicals. Selected chemicals all act on photosynthesis and thus share a common physiological target, but display distinct toxicity mechanisms. Results showed that UVR pre-exposure for four days partially inhibited algal growth and photosynthesis, but also increased algal tolerance to higher UVR levels, confirming UVR acclimation. HPLC analysis of algal pigments indicated that UVR acclimation might in part be explained by the protective function of lutein while the contribution of UVR absorbing compounds was less clear. Challenge exposure to chemicals in the absence of UVR showed that acclimated algae were co-tolerant to the photosensitizer rose bengal, but not to the

A review of accidents, prevention and mitigation options related to hazardous gases

International Nuclear Information System (INIS)

Fthenakis, V.M.

1993-05-01

Statistics on industrial accidents are incomplete due to lack of specific criteria on what constitutes a release or accident. In this country, most major industrial accidents were related to explosions and fires of flammable materials, not to releases of chemicals into the environment. The EPA in a study of 6,928 accidental releases of toxic chemicals revealed that accidents at stationary facilities accounted for 75% of the total number of releases, and transportation accidents for the other 25%. About 7% of all reported accidents (468 cases) resulted in 138 deaths and 4,717 injuries ranging from temporary respiratory problems to critical injuries. In-plant accidents accounted for 65% of the casualties. The most efficient strategy to reduce hazards is to choose technologies which do not require the use of large quantities of hazardous gases. For new technologies this approach can be implemented early in development, before large financial resources and efforts are committed to specific options. Once specific materials and options have been selected, strategies to prevent accident initiating events need to be evaluated and implemented. The next step is to implement safety options which suppress a hazard when an accident initiating event occurs. Releases can be prevented or reduced with fail-safe equipment and valves, adequate warning systems and controls to reduce and interrupt gas leakage. If an accident occurs and safety systems fail to contain a hazardous gas release, then engineering control systems will be relied on to reduce/minimize environmental releases. As a final defensive barrier, the prevention of human exposure is needed if a hazardous gas is released, in spite of previous strategies. Prevention of consequences forms the final defensive barrier. Medical facilities close by that can accommodate victims of the worst accident can reduce the consequences of personnel exposure to hazardous gases

Accident Management ampersand Risk-Based Compliance With 40 CFR 68 for Chemical Process Facilities

International Nuclear Information System (INIS)

O'Kula, K.R.; Taylor, R.P. Jr.; Ashbaugh, S.G.

1995-01-01

A risk-based logic model is suggested as an appropriate basis for better predicting accident progression and ensuing source terms to the environment from process upset conditions in complex chemical process facilities. Under emergency conditions, decision-makers may use the Accident Progression Event Tree approach to identify the best countermeasure for minimizing deleterious consequences to receptor groups before the atmospheric release has initiated. It is concluded that the chemical process industry may use this methodology as a supplemental information provider to better comply with the Environmental Protection Agency's proposed 40 CFR 68 Risk Management Program rule. An illustration using a benzene-nitric acid potential interaction demonstrates the value of the logic process. The identification of worst-case releases and planning for emergency response are improved through these methods, at minimum. It also provides a systematic basis for prioritizing facility modifications to correct vulnerabilities

A Risk Assessment Methodology for Toxic Chemicals Evaporation ...

African Journals Online (AJOL)

This study presents a method for determining the mass transfer coefficient for the toxic chemicals evaporation from circular pools formed due to the failure of plant integrity or escape from valves. The approach used in this present research work is to develop a correlation by a robust optimization technique known as Genetic ...

2001 Toxic Chemical Release Inventory Emergency Planning and Community Right to Know Act SEC 313

International Nuclear Information System (INIS)

ZALOUDEK, D.E.

2002-01-01

Pursuant to section 313 of the Emergency Planning and Community Right-To-Know Act of 1986 (EPCRA), and Executive Order 13148, Greening the Government Through Leadership in Environmental Management, the US Department of Energy has prepared and submitted a Toxic Chemical Release Inventory for the Hanford Site covering activities performed during calendar year 2001. EPCRA Section 313 requires facilities that manufacture, process, or otherwise use listed toxic chemicals in quantities exceeding established threshold levels to report total annual releases of those chemicals. During calendar year 2001, Hanford Site activities resulted in one chemical used in amounts exceeding an activity threshold. Accordingly, the Hanford Site 2001 Toxic Chemical Release Inventory, DOE/RL-2002-37, includes total annual amount of lead released to the environment, transferred to offsite locations, and otherwise managed as waste

[Characterization of severe acute occupational poisoning accidents related to organic solvents in China between 1989 and 2003].

Science.gov (United States)

Wang, Huan-Qiang; Li, Tao; Zhang, Min; Wang, Hong-Fei; Chen, Shu-Yang; Du, Xie-Yi; Wang, Dan; Zhang, Shuang; Qin, Jian

2006-12-01

To analyze severe acute occupational poisoning accidents related to organic solvents reported in China between 1989 and 2003, and to study the characteristics of severe acute occupational poisoning accidents and provide scientific evidences for prevention and control strategies. The data from the national occupational poisoning case reporting system were analyzed with descriptive methods. (1) There were 58 severe acute occupational poisoning accidents related to organic solvents for 15 years with 393 workers poisoned and 48 workers died. The total poisoning rate was 51.2%, and the total mortality was 12.2%. The average poisoning age was (30.9 +/- 8.8) years old and the average death age was (30.6 +/- 12.0) years old. (2) There were 11 types of chemicals that caused these poisoning accidents, and most of the accidents were caused by benzene and homologs. (3) Most of the accidents occurred in manufacture, chemical industry, construction industry, transportation and storage industry, service and commerce. The risk was higher in some jobs than in others, such as paint spraying and cleanout. The poisoning accidents occurred more frequently from April to July each year. (4) The main causes of the accidents were poor ventilation (23.6%), lack of personal protection equipment (21.2%), lack of safety education (19.2%), and lack of safety work practice (15.8%) etc. The ventilation at the workplace involved in organic solvents should be maintained and the skin contacting directly with the organic solvents should be avoided, and it is encouraged to replace the poison with the nontoxic or lower toxic chemicals.

Improved worst-case and liely accident definition in complex facilities for 40 CFR 68 compliance

International Nuclear Information System (INIS)

O'Kula, K.R., Taylor, Robert P., Jr; Hang, P.

1997-04-01

Many DOE facilities potentially subject to compliance with offsite consequence criteria under the 40 CFR 68 Risk Management Program house significant inventories of toxic and flammable chemicals. The accident progression event tree methodology is suggested as a useful technical basis to define Worst-Case and Alternative Release Scenarios in facilities performing operations beyond simple storage and/or having several barriers between the chemical hazard and the environment. For multiple chemical release scenarios, a chemical mixture methodology should be applied to conservatively define concentration isopleths. In some instances, the region requiring emergency response planning is larger under this approach than if chemicals are treated individually

Toxics release inventory: List of toxic chemicals within the polychlorinated alkanes category and guidance for reporting

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-02-01

Section 313 of the Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA) requires certain facilities manufacturing, processing, or otherwise using listed toxic chemicals to report their environmental releases of such chemicals annually. On November 30, 1994 EPA added 286 chemicals and chemical categories. Six chemical categories (nicotine and salts, strychnine and salts, polycyclic aromatic compounds, water dissociable nitrate compounds, diisocyanates, and polychlorinated alkanes) are included in these additions. At the time of the addition, EPA indicated that the Agency would develop, as appropriate, interpretations and guidance that the Agency determines are necessary to facilitate accurate reporting for these categories. This document constitutes such guidance for the polychlorinated alkanes category.

Linear solvation energy relationships for toxicity of selected organic chemicals to Daphnia pulex and Daphnia magna

Science.gov (United States)

Passino, Dora R.M.; Hickey, James P.; Frank, Anthony M.

1988-01-01

In the Laurentian Great Lakes, more than 300 contaminants have been identified in fish, other biota, water, and sediment. Current hazard assessment of these chemicals by the National Fisheries Research Center-Great Lakes is based on their toxicity, occurrence in the environment, and source. Although scientists at the Center have tested over 70 chemicals with the crustacean Daphnia pulex, the number of experimental data needed to screen the huge array of chemicals in the Great Lakes exceeds the practical capabilities of conducting bioassays. This limitation can be partly circumvented, however, by using mathematical models based on quantitative structure-activity relationships (QSAR) to provide rapid, inexpensive estimates of toxicity. Many properties of chemicals, including toxicity, bioaccumulation and water solubility are well correlated and can be predicted by equations of the generalized linear solvation energy relationships (LSER). The equation we used to model solute toxicity is Toxicity = constant + mVI/100 + s (π* + dδ) + bβm + aαm where VI = intrinsic (Van der Waals) molar volume; π* = molecular dipolarity/polarizability; δ = polarizability 'correction term'; βm = solute hydrogen bond acceptor basicity; and αm = solute hydrogen bond donor acidity. The subscript m designates solute monomer values for α and β. We applied the LSER model to 48-h acute toxicity data (measured as immobilization) for six classes of chemicals detected in Great Lakes fish. The following regression was obtained for Daphnia pulex (concentration = μM): log EC50 = 4.86 - 4.35 VI/100; N = 38, r2 = 0.867, sd = 0.403 We also used the LSER modeling approach to analyze to a large published data set of 24-h acute toxicity for Daphnia magna; the following regression resulted, for eight classes of compounds (concentration = mM): log EC50 = 3.88 - 4.52 VI/100 - 1.62 π* + 1.66 βm - 0.916 αm; N = 62, r2 = 0.859, sd = 0.375 In addition we developed computer software that identifies

The complex interaction between marine debris and toxic chemicals in the ocean.

Science.gov (United States)

Engler, Richard E

2012-11-20

Marine debris, especially plastic debris, is widely recognized as a global environmental problem. There has been substantial research on the impacts of plastic marine debris, such as entanglement and ingestion. These impacts are largely due to the physical presence of plastic debris. In recent years there has been an increasing focus on the impacts of toxic chemicals as they relate to plastic debris. Some plastic debris acts as a source of toxic chemicals: substances that were added to the plastic during manufacturing leach from plastic debris. Plastic debris also acts as a sink for toxic chemicals. Plastic sorbs persistent, bioaccumulative, and toxic substances (PBTs), such as polychlorinated biphenyls (PCBs) and dioxins, from the water or sediment. These PBTs may desorb when the plastic is ingested by any of a variety of marine species. This broad look at the current research suggests that while there is significant uncertainty and complexity in the kinetics and thermodynamics of the interaction, plastic debris appears to act as a vector transferring PBTs from the water to the food web, increasing risk throughout the marine food web, including humans. Because of the extremely long lifetime of plastic and PBTs in the ocean, prevention strategies are vital to minimizing these risks.

Combinatorial QSAR modeling of chemical toxicants tested against Tetrahymena pyriformis.

Science.gov (United States)

Zhu, Hao; Tropsha, Alexander; Fourches, Denis; Varnek, Alexandre; Papa, Ester; Gramatica, Paola; Oberg, Tomas; Dao, Phuong; Cherkasov, Artem; Tetko, Igor V

2008-04-01

Selecting most rigorous quantitative structure-activity relationship (QSAR) approaches is of great importance in the development of robust and predictive models of chemical toxicity. To address this issue in a systematic way, we have formed an international virtual collaboratory consisting of six independent groups with shared interests in computational chemical toxicology. We have compiled an aqueous toxicity data set containing 983 unique compounds tested in the same laboratory over a decade against Tetrahymena pyriformis. A modeling set including 644 compounds was selected randomly from the original set and distributed to all groups that used their own QSAR tools for model development. The remaining 339 compounds in the original set (external set I) as well as 110 additional compounds (external set II) published recently by the same laboratory (after this computational study was already in progress) were used as two independent validation sets to assess the external predictive power of individual models. In total, our virtual collaboratory has developed 15 different types of QSAR models of aquatic toxicity for the training set. The internal prediction accuracy for the modeling set ranged from 0.76 to 0.93 as measured by the leave-one-out cross-validation correlation coefficient ( Q abs2). The prediction accuracy for the external validation sets I and II ranged from 0.71 to 0.85 (linear regression coefficient R absI2) and from 0.38 to 0.83 (linear regression coefficient R absII2), respectively. The use of an applicability domain threshold implemented in most models generally improved the external prediction accuracy but at the same time led to a decrease in chemical space coverage. Finally, several consensus models were developed by averaging the predicted aquatic toxicity for every compound using all 15 models, with or without taking into account their respective applicability domains. We find that consensus models afford higher prediction accuracy for the

THE FUTURE OF TOXICOLOGY-PREDICTIVE TOXICOLOGY: AN EXPANDED VIEW OF CHEMICAL TOXICITY

Science.gov (United States)

A chemistry approach to predictive toxicology relies on structure−activity relationship (SAR) modeling to predict biological activity from chemical structure. Such approaches have proven capabilities when applied to well-defined toxicity end points or regions of chemical space. T...

Handbook of acute toxicity of chemicals to fish and aquatic invertebrates : summaries of toxicity tests conducted at Columbia National Fisheries Research Laboratory, 1965-78

Science.gov (United States)

Johnson, W. Waynon; Finley, Mack T.

1980-01-01

Acute toxicity is a major subject of research at Columbia National Fisheries Research Laboratory for evaluating the impact of toxic chemicals on fishery resources. The Laboratory has played a leading role in developing research technology for toxicity testing and data interpretation. In 1965-78, more than 400 chemicals were tested against a variety of invertebrates and fish species representative of both cold- and warm-water climates.The use of acute toxicity tests for assessing the potential hazard of chemical contaminants to aquatic organisms is well documented (Boyd 1957; Henderson et al. 1960; Sanders and Cope 1966; Macek and McAllister 1970). Static acute toxicity tests provide rapid and (within limits) reproducible concentration-response curves for estimating toxic effects of chemicals on aquatic organisms. These tests provide a database for determining relative toxicity of a large number of chemicals to a variety of species and for estimating acute effects of chemical spills on natural aquatic systems; they also assist in determining priority and design of additional toxicity studies.Acute toxicity tests usually provide estimates of the exposure concentration causing 50% mortality (LC50) to test organisms during a specified period of time. For certain invertebrates, the effective concentration is based on immobilization, or some other identifiable endpoint, rather than on lethality. The application of the LC50 has gained acceptance among toxicologists and is generally the most highly rated test for assessing potential adverse effects of chemical contaminants to aquatic life (Brungs and Mount 1978; American Institute for Biological Sciences 1978a).The literature contains numerous papers dealing with the acute toxicity of chemicals to freshwater organisms. However, there is a tremendous need for a concise compendium of toxicity data covering a large variety of chemicals and test species. This Handbook is a compilation of a large volume of acute toxicity data

Comparing rankings of selected TRI organic chemicals for two environments using a level III fugacity model and toxicity

International Nuclear Information System (INIS)

Edwards, F.G.; Egemen, E.; Nirmalakhandan, N.

1998-01-01

The Toxics Release Inventory, TRI (USEPA, 1995) is a comprehensive listing of chemicals, mass released, source of releases, and other related information for chemicals which are released into the environment in the US. These chemicals are then ranked according to the mass released as a indication of their environmental impact. Industries have been encouraged to adopt production methods to decrease the release of chemicals which are ranked highly in the TRI. Clearly, this ranking of the chemicals based upon the mass released fails to take into account very important environmental aspects. The first and most obvious aspect is the wide range of toxicity's of the chemicals released. Numerous researchers have proposed systems to rank chemicals according to their toxicity. The second aspect, which a mass released based ranking does not take into account, is the fate and transport of each chemical within the environment. Cohen and Ryan (1985) and Mackay and Paterson (1991) have proposed models to evaluate the fate and transport of chemicals released into the environment. Some authors have incorporated the mass released and toxicity with some fate and transport aspects to rank the impact of released chemicals. But, due to the complexities of modeling the environment, the lack of published data on properties of chemicals, and the lack of information on the speciation of chemicals in complex systems, modeling the fate and transport of toxic chemicals in the environment remains difficult. To provide an indication of the need to rank chemicals according to their environmental impact instead of the mass released, the authors have utilized a subset of 45 organic chemicals from the TRI, modeled the fate and transport of the chemicals using a Level III fugacity model, and compared those equilibrium concentrations with toxicity data to yield a hazard value for each chemical

Chemical composition and toxicities of essential oil of Illicium ...

African Journals Online (AJOL)

The aim of this research was to determine the chemical composition and toxicities of essential oil derived from Illicium fargesii Finet et Gagnep fruits against the maize weevil (Sitophilus zeamais Motsch). Essential oil of I. fargesii fruits was obtained from hydrodistillation and was investigated by GC (Gas Chromatography) ...

VAPOR SAMPLING DEVICE FOR INTERFACE WITH MICROTOX ASSAY FOR SCREENING TOXIC INDUSTRIAL CHEMICALS

Science.gov (United States)

A time-integrated sampling system interfaced with a toxicity-based assay is reported for monitoring volatile toxic industrial chemicals (TICs). Semipermeable membrane devices (SPMDs) using dimethyl sulfoxide (DMSO) as the fill solvent accumulated each of 17 TICs from the vapor...

Toxicity challenges in environmental chemicals: Prediction of ...

Science.gov (United States)

Physiologically based pharmacokinetic (PBPK) models bridge the gap between in vitro assays and in vivo effects by accounting for the adsorption, distribution, metabolism, and excretion of xenobiotics, which is especially useful in the assessment of human toxicity. Quantitative structure-activity relationships (QSAR) serve as a vital tool for the high-throughput prediction of chemical-specific PBPK parameters, such as the fraction of a chemical unbound by plasma protein (Fub). The presented work explores the merit of utilizing experimental pharmaceutical Fub data for the construction of a universal QSAR model, in order to compensate for the limited range of high-quality experimental Fub data for environmentally relevant chemicals, such as pollutants, pesticides, and consumer products. Independent QSAR models were constructed with three machine-learning algorithms, k nearest neighbors (kNN), random forest (RF), and support vector machine (SVM) regression, from a large pharmaceutical training set (~1000) and assessed with independent test sets of pharmaceuticals (~200) and environmentally relevant chemicals in the ToxCast program (~400). Small descriptor sets yielded the optimal balance of model complexity and performance, providing insight into the biochemical factors of plasma protein binding, while preventing over fitting to the training set. Overlaps in chemical space between pharmaceutical and environmental compounds were considered through applicability of do

The effects on health of radiological and chemical toxicity

International Nuclear Information System (INIS)

Toledano, M.; Flury-Herard, A.

2003-01-01

Future trends in the protection against the effects on health of radiological and/or chemical toxicity will certainly be based on improved knowledge of specific biological mechanisms and individual sensitivity. Progress in these areas will most likely be made at the interfaces between research, health care and biomedical monitoring. (authors)

78 FR 64210 - Extension of Review Periods Under the Toxic Substances Control Act; Certain Chemicals and...

Science.gov (United States)

2013-10-28

... Under the Toxic Substances Control Act; Certain Chemicals and Microorganisms; Premanufacture... 325 and 324110), e.g., chemical manufacturing and petroleum refineries. The North American Industrial... Agency under section 5 of the Toxic Substances Control Act (TSCA), received by EPA on or before October 1...

Brand switching and toxic chemicals in cigarette smoke: A national study.

Science.gov (United States)

Mendel, Jennifer R; Baig, Sabeeh A; Hall, Marissa G; Jeong, Michelle; Byron, M Justin; Morgan, Jennifer C; Noar, Seth M; Ribisl, Kurt M; Brewer, Noel T

2018-01-01

US law requires disclosure of quantities of toxic chemicals (constituents) in cigarette smoke by brand and sub-brand. This information may drive smokers to switch to cigarettes with lower chemical quantities, under the misperception that doing so can reduce health risk. We sought to understand past brand-switching behavior and whether learning about specific chemicals in cigarette smoke increases susceptibility to brand switching. Participants were US adult smokers surveyed by phone (n = 1,151, probability sample) and online (n = 1,561, convenience sample). Surveys assessed whether smokers had ever switched cigarette brands or styles to reduce health risk and about likelihood of switching if the smoker learned their brand had more of a specific chemical than other cigarettes. Chemicals presented were nicotine, carbon monoxide, lead, formaldehyde, arsenic, and ammonia. Past brand switching to reduce health risk was common among smokers (43% in phone survey, 28% in online survey). Smokers who were female, over 25, and current "light" cigarette users were more likely to have switched brands to reduce health risks (all p brand switching based on information about particular chemicals. In both samples, lead, formaldehyde, arsenic, and ammonia led to more susceptibility to switch than nicotine (all p brands or styles to reduce health risks. The majority said they might or would definitely switch brands if they learned their cigarettes had more of a toxic chemical than other brands. Brand switching is a probable unintended consequence of communications that show differences in smoke chemicals between brands.

Emergency planning and the Control of Major Accident Hazards (COMAH/Seveso II) Directive: An approach to determine the public safety zone for toxic cloud releases

International Nuclear Information System (INIS)

O'Mahony, Mary T.; Doolan, Donal; O'Sullivan, Alice; Hession, Michael

2008-01-01

The EU Control of Major Accidents Hazards Directive (Seveso II) requires an external emergency plan for each top tier site. This paper sets out a method to build the protection of public health into emergency planning for Seveso sites in the EU. The method involves the review of Seveso site details prescribed under the directive. The site safety report sets out the potential accident scenarios. The safety report's worst-case scenario, and chemical involved, is used as the basis for the external emergency plan. A decision was needed on the appropriate threshold value to use as the level of concern to protect public health. The definitions of the regulatory standards (air quality standards and occupational standards) in use were studied, how they are derived and for what purpose. The 10 min acute exposure guideline level (AEGL) for a chemical is recommended as the threshold value to inform decisions taken to protect public health from toxic cloud releases. The area delimited by AEGL 1 defines the population who may be concerned about being exposed. They need information based on comprehensive risk assessment. The area delimited by AEGL 2 defines the population for long-term surveillance when indicated and may include first responders. The area delimited by AEGL 3 defines the population who may present acutely to the medical services. It ensures that the emergency responders site themselves safely. A standard methodology facilitates discussions with plant operators and concerned public. Examples show how the methodology can be adapted to suit explosive risk and response to fire

Antioxidants as potential medical countermeasures for chemical warfare agents and toxic industrial chemicals.

Science.gov (United States)

McElroy, Cameron S; Day, Brian J

2016-01-15

The continuing horrors of military conflicts and terrorism often involve the use of chemical warfare agents (CWAs) and toxic industrial chemicals (TICs). Many CWA and TIC exposures are difficult to treat due to the danger they pose to first responders and their rapid onset that can produce death shortly after exposure. While the specific mechanism(s) of toxicity of these agents are diverse, many are associated either directly or indirectly with increased oxidative stress in affected tissues. This has led to the exploration of various antioxidants as potential medical countermeasures for CWA/TIC exposures. Studies have been performed across a wide array of agents, model organisms, exposure systems, and antioxidants, looking at an almost equally diverse set of endpoints. Attempts at treating CWAs/TICs with antioxidants have met with mixed results, ranging from no effect to nearly complete protection. The aim of this commentary is to summarize the literature in each category for evidence of oxidative stress and antioxidant efficacy against CWAs and TICs. While there is great disparity in the data concerning methods, models, and remedies, the outlook on antioxidants as medical countermeasures for CWA/TIC management appears promising. Copyright © 2015 Elsevier Inc. All rights reserved.

How the chemical industry can benefit from PRA

International Nuclear Information System (INIS)

Guymer, P.; Kaiser, G.D.; Mc Kelvey, T.W.; Hannaman, G.W.

1986-01-01

Probabilistic Risk Assessment (PRA) is a method of quantifying the frequency of occurrence and the magnitude of the consequences of accidents in systems that contain hazardous materials such as radioactive fission products, and toxic, flammable or explosive chemicals. The frequency and the magnitude of the consequences are the basic elements of any definition or risk, which is often simply expressed as the product of frequency and magnitude, summed over all accident sequences. PRA is now a mature technique that has been used to estimate risk for a number of industrial facilities. In this paper the author gives examples of beneficial uses of PRA

Preventing external domino accidents : A framework for enhancing cooperation in the Chemical Process Industry (CPI)

NARCIS (Netherlands)

Reniers, G.; Dullaert, W.; Soudan, K.

2005-01-01

Empirical research on major accident safety in the second largest chemical cluster worldwide, the Antwerp port area, supports the design of a meta-technical framework for optimizing external domino prevention. First, the majority of Seveso top tier companies have expressed a willingness to cooperate

Toxicity assessment of industrial chemicals and airborne contaminants: transition from in vivo to in vitro test methods: a review.

Science.gov (United States)

Bakand, S; Winder, C; Khalil, C; Hayes, A

2005-12-01

Exposure to occupational and environmental contaminants is a major contributor to human health problems. Inhalation of gases, vapors, aerosols, and mixtures of these can cause a wide range of adverse health effects, ranging from simple irritation to systemic diseases. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there are approximately 80,000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from both economical and practical perspectives. While in vitro methods are capable of rapidly providing toxicity information, regulatory agencies in general are still cautious about the replacement of whole-animal methods with new in vitro techniques. Although studying the toxic effects of inhaled chemicals is a complex subject, recent studies demonstrate that in vitro methods may have significant potential for assessing the toxicity of airborne contaminants. In this review, current toxicity test methods for risk evaluation of industrial chemicals and airborne contaminants are presented. To evaluate the potential applications of in vitro methods for studying respiratory toxicity, more recent models developed for toxicity testing of airborne contaminants are discussed.

Multi-objective evacuation routing optimization for toxic cloud releases

International Nuclear Information System (INIS)

Gai, Wen-mei; Deng, Yun-feng; Jiang, Zhong-an; Li, Jing; Du, Yan

2017-01-01

This paper develops a model for assessing the risks associated with the evacuation process in response to potential chemical accidents, based on which a multi-objective evacuation routing model for toxic cloud releases is proposed taking into account that the travel speed on each arc will be affected by disaster extension. The objectives of the evacuation routing model are to minimize travel time and individual evacuation risk along a path respectively. Two heuristic algorithms are proposed to solve the multi-objective evacuation routing model. Simulation results show the effectiveness and feasibility of the model and algorithms presented in this paper. And, the methodology with appropriate modification is suitable for supporting decisions in assessing emergency route selection in other cases (fires, nuclear accidents). - Highlights: • A model for assessing and visualizing the risks is developed. • A multi-objective evacuation routing model is proposed for toxic cloud releases. • A modified Dijkstra algorithm is designed to obtain an solution of the model. • Two heuristic algorithms have been developed as the optimization tool.

Emergency preparedness and response in case of a fire accident with UF6 packages traversing the Suez Canal

International Nuclear Information System (INIS)

Salama, M.

2004-01-01

Egypt has a unique problem, the Suez Canal. Radioactive cargo passes regularly through the canal carrying new and spent reactor fuel. There are also about 1000 metric tonnes of uranium hexafluoride (UF 6 ) passing through the canal every year. In spite of all the precautions taken in the transport, accidents with packages containing UF 6 shipped through the Suez Canal may arise, even though the probability is minimal. Such accidents may be accompanied by injuries to or death of persons and damage to property including radiation and criticality hazards and high chemical toxicity, particularly if the accident occurred close to one of the three densely populated cities (Port Said, Ismailia and Suez), which are located along the west bank of the Suez Canal. The government of Egypt has established a national radiological emergency plan in order to deal with any radiological accidents which may arise inside the country. This paper considers the effect of a fire accident to industrial packages containing UF 6 on board a cargo ship passing along the Suez Canal near Port Said City. The accident scenario and emergency response actions taken during the different phases of the accident are presented and discussed. The paper highlights the importance of public awareness for populations located in densely populated areas along the bank of the Suez Canal, in order to react in a timely and effective way to avoid the toxic and radiological hazards resulting from such a type of accident. The possibility of upgrading the capabilities of civil defence and fire-fighting personnel is also discussed (author)

Host Response to Environmental Hazards: Using Literature, Bioinformatics, and Computation to Derive Candidate Biomarkers of Toxic Industrial Chemical Exposure

Science.gov (United States)

2015-10-01

military threat chemicals with adverse health effects and clinical outcomes to improve diagnostic potential after exposure to toxic industrial...end organ injury following chemical exposures in the field. Markers of end-organ injury and toxicity and other health effects markers, particularly...Biomarkers of Toxic Industrial Chemical Exposure Major Jonathan D. Stallings *1 , Danielle L. Ippolito 1 , Anders Wallqvist 2 , B. Claire McDyre 3 , and

Effects-driven chemical fractionation of heavy fuel oil to isolate compounds toxic to trout embryos.

Science.gov (United States)

Bornstein, Jason M; Adams, Julie; Hollebone, Bruce; King, Thomas; Hodson, Peter V; Brown, R Stephen

2014-04-01

Heavy fuel oil (HFO) spills account for approximately 60% of ship-source oil spills and are up to 50 times more toxic than medium and light crude oils. Heavy fuel oils contain elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) and alkyl-PAHs, known to be toxic to fish; however, little direct characterization of HFO toxicity has been reported. An effects-driven chemical fractionation was conducted on HFO 7102 to separate compounds with similar chemical and physical properties, including toxicity, to isolate the groups of compounds most toxic to trout embryos. After each separation, toxicity tests directed the next phase of fractionation, and gas chromatography-mass spectrometry analysis correlated composition with toxicity, with a focus on PAHs. Low-temperature vacuum distillation permitted the separation of HFO into 3 fractions based on boiling point ranges. The most toxic of these fractions underwent wax precipitation to remove long-chain n-alkanes. The remaining PAH-rich extract was further separated using open column chromatography, which provided distinct fractions that were grouped according to increasing aromatic ring count. The most toxic of these fractions was richest in PAHs and alkyl-PAHs. The results of the present study were consistent with previous crude oil studies that identified PAH-rich fractions as the most toxic. © 2013 SETAC.

Toxicity and chemical analyses of airport runoff waters in Poland.

Science.gov (United States)

Sulej, Anna Maria; Polkowska, Zaneta; Wolska, Lidia; Cieszynska, Monika; Namieśnik, Jacek

2014-05-01

The aim of this study was to assess the ecotoxicological effects of various compounds in complex airport effluents using a chemical and ecotoxicological integrated strategy. The present work deals with the determination of sum of PCBs, PAHs, pesticides, cations, anions, phenols, anionic, cationic, non-ionic detergents, formaldehyde and metals--as well as TOC and conductivity--in runoff water samples collected from 2009 to 2011 at several locations on two Polish international airports. Two microbiotests (Vibrio fischeri bacteria and the crustacean Thamnocephalus platyurus) have been used to determine the ecotoxicity of airport runoff waters. The levels of many compounds exceeded several or even several tens of times the maximum permissible levels. Analysis of the obtained data shows that samples that displayed maximum toxicity towards the bioindicators Vibrio fischeri were not toxic towards Thamnocephalus platyurus. Levels of toxicity towards T. platyurus are strongly correlated with pollutants that originate from the technological operations related to the maintenance of airport infrastructure. The integrated (chemical-ecotoxicological) approach to environmental contamination assessment in and around airports yields extensive information on the quality of the environment. These methodologies can be then used as tools for tracking the environmental fate of these compounds and for assessing the environmental effect of airports. Subsequently, these data will provide a basis for airport infrastructure management.

Physical and chemical parameters of sediment extraction and fractionation that influence toxicity, as evaluated by microtox (trade name)

International Nuclear Information System (INIS)

Ho, K.T.Y.; Quinn, J.G.

1993-01-01

Several physical and chemical parameters of sediment extraction and fractionation of organic compounds that influence bioassay results were evaluated. Each parameter was evaluated with a photoluminescent bacterial bioassay (Microtox) as an end point. Three solvents (acetonitrile, acetone, and methanol) were studied for their ability to extract toxic organic components from marine sediments. Acetone extracted the most toxicity, with no difference between acetonitrile and methanol. Two methods of fractionating sediment extracts (silica-gel-column chromatography (SGCC) and acid-base fractionation) were compared. SGCC was more useful because it resulted in a wider range of responses and was faster to perform than acid-base fractionation. Microtox was used to rank four marine sediments with respect to toxicity and to determine if one chemical class (or fraction) was consistently more toxic among different sediments. With some caveats, Microtox results agreed with general chemical concentration trends and other bioassay results in distinguishing between contaminated and noncontaminated sediments. Although results indicated there was not a consistently most toxic fraction among sediments, there was a consistently least toxic fraction. The effect of sediment storage time on toxicity was also evaluated. Results indicated that the most stable chemical fraction (containing nonpolar hydrocarbons) did not change toxicologically for 30 weeks, whereas the more chemically active fraction (containing ketones, quinones, and carboxyls) changed as soon as one week

Acute oral toxicity of chemicals in terrestrial life stages of amphibians: Comparisons to birds and mammals.

Science.gov (United States)

Crane, Mark; Finnegan, Meaghean; Weltje, Lennart; Kosmala-Grzechnik, Sylwia; Gross, Melanie; Wheeler, James R

2016-10-01

Amphibians are currently the most threatened and rapidly declining group of vertebrates and this has raised concerns about their potential sensitivity and exposure to plant protection products and other chemicals. Current environmental risk assessment procedures rely on surrogate species (e.g. fish and birds) to cover the risk to aquatic and terrestrial life stages of amphibians, respectively. Whilst a recent meta-analysis has shown that in most cases amphibian aquatic life stages are less sensitive to chemicals than fish, little research has been conducted on the comparative sensitivity of terrestrial amphibian life stages. Therefore, in this paper we address the questions "What is the relative sensitivity of terrestrial amphibian life stages to acute chemical oral exposure when compared with mammals and birds?" and "Are there correlations between oral toxicity data for amphibians and data for mammals or birds?" Identifying a relationship between these data may help to avoid additional vertebrate testing. Acute oral amphibian toxicity data collected from the scientific literature and ecotoxicological databases were compared with toxicity data for mammals and birds. Toxicity data for terrestrial amphibian life stages are generally sparse, as noted in previous reviews. Single-dose oral toxicity data for terrestrial amphibian life stages were available for 26 chemicals and these were positively correlated with LD50 values for mammals, while no correlation was found for birds. Further, the data suggest that oral toxicity to terrestrial amphibian life stages is similar to or lower than that for mammals and birds, with a few exceptions. Thus, mammals or birds are considered adequate toxicity surrogates for use in the assessment of the oral exposure route in amphibians. However, there is a need for further data on a wider range of chemicals to explore the wider applicability of the current analyses and recommendations. Copyright © 2016 Elsevier Inc. All rights reserved.

Children's vulnerability to toxic chemicals: a challenge and opportunity to strengthen health and environmental policy.

Science.gov (United States)

Landrigan, Philip J; Goldman, Lynn R

2011-05-01

A key policy breakthrough occurred nearly twenty years ago with the discovery that children are far more sensitive than adults to toxic chemicals in the environment. This finding led to the recognition that chemical exposures early in life are significant and preventable causes of disease in children and adults. We review this knowledge and recommend a new policy to regulate industrial and consumer chemicals that will protect the health of children and all Americans, prevent disease, and reduce health care costs. The linchpins of a new US chemical policy will be: first, a legally mandated requirement to test the toxicity of chemicals already in commerce, prioritizing chemicals in the widest use, and incorporating new assessment technologies; second, a tiered approach to premarket evaluation of new chemicals; and third, epidemiologic monitoring and focused health studies of exposed populations.

Accident simulation in a chemical process facility at the Savannah River Site

International Nuclear Information System (INIS)

Hope, E.P.

1993-01-01

The US Department of Energy requires Westinghouse Savannah River Company to safely operate the chemical separations facilities at the Savannah River Site (SRS). As part of the safety analysis program, simulation of a proposed frame waste recovery (FWR) system is needed to determine the possible accident consequences that may affect public safety. This paper details the simulation process for the proposed frame waste recovery process and describes the analytical tools used in order to make estimates of accident consequences. Since the process in question has been operated, historical data and statistics about its operation are available. Software tools have been developed to allow analysis of the frame waste recovery system, including the generation of system specific dose conversion factors for a number of unique situations. Accident scenarios involving spilled liquid material are analyzed and account for the specific floor geometry of the facility. Confinement and filtration systems are considered. Analysis of source terms is a limiting factor which affects the entire evaluation process. In the past, facility source terms were generally constant with occasional variations from established patterns. As new site missions unfold, significant variations in source terms can be expected. The impact of these variations on the safety analysis is discussed

The significance of domino effect in chemical accidents

OpenAIRE

Hemmatian, Behrouz; Abdolhamidzadeh, B; Darbra Roman, Rosa Maria; Casal Fàbrega, Joaquim

2014-01-01

A historical survey was performed on 330 accidents involving domino effect, occurred in process/storage plants and in the transportation of hazardous materials; only accidents occurred after 1st-January-1961 have been considered. The main features – geographical location, type of accident, materials involved, origin and causes, consequences, domino sequences – were analyzed, with special consideration to the situation in the developing countries and compared to those from other previous surve...

Upper parameters of toxicity (LDsub(50/30)) of some radioactive and chemical substances

International Nuclear Information System (INIS)

Rodionova, L.F.; Kupriyanova, V.M.; Zasedatelev, A.A.

1978-01-01

The toxicities of radioactive ( 90 Sr, 210 Po) and chemical (lead nitrate, mercuric chloride) substances were compared using equivalent procedures. Ninety six doses of toxic substances in various concentrations were tested on mice to which these substances were administered by intragastric intubation. The material was processed and analyzed by conventional methods used in toxicology. The upper limits of toxicity for the tested substances were determined from their LDsub(50/30) values by various methods of calculation

Lethal toxicity of industrial chemicals to early life stages of Tilapia guineensis.

Science.gov (United States)

Ezemonye, L I N; Ogeleka, D F; Okieimen, F E

2008-08-30

The toxic effects of industrial chemicals on three early life stages of an economically important fish, Tilapia guineensis were investigated using the Organisation for Economic Cooperation and Development (OECD) # 203 recommended semi-static renewal bioassay. The assessment was necessary for the uncontrollable disposal of Neatex (liquid detergent) and Norust CR 486 (corrosion inhibitor) into the Niger Delta environment of Nigeria. The estimated 96-h LC(50) for 7-, 14- and 28-day-old fish in Norust CR 486 exposure was considered "more toxic" than Neatex in all life stages and was dependent on species age, exposure duration and environment. In the fresh water test, for Neatex and Norust CR 486 exposures for day 7, 14 and 28, the 96-h LC50 were 8.79, 17.10 and 82.42 mg/l and 5.55, 13.58 and 20.21 mg/l, respectively. In the brackish test, 15.42 and 46.52 mg/l, not determined (ND) and 7.35, 13.95 and 24.50mg/l were obtained. Differential toxicity was observed in the fresh and brackish water fish for the two chemicals and controls at pchemicals provides a rationale for regulatory surveillance and monitoring of both chemicals in the fragile Niger Delta environment.

The toxic and radiological risk equivalence approach in UF6 transport

International Nuclear Information System (INIS)

Ringot, C.; Hamard, J.

1988-12-01

After a brief description of the safety in transport of UF 6 , we discuss the equivalence of the radioactive and chemical risks in UF 6 transport regulations. As the concept of low specific activity appears to be ill-suited for a toxic gas, we propose a quantity of material limit designated T 2 (equivalent to A 2 for radioactive substances) for packagings unable to withstand accident conditions (9 m drop, 800 0 C fire environment for 30 minutes). It is proposed that this limit be chosen for the amount of release acceptable after AIEA tests. Different possible scenarios are described, with fire assumed to be the most severe toxic risk situation

Chemical mixtures in untreated water from public-supply wells in the U.S. - Occurrence, composition, and potential toxicity

Energy Technology Data Exchange (ETDEWEB)

Toccalino, Patricia L., E-mail: ptocca@usgs.gov [U.S. Geological Survey (USGS), 6000 J Street, Placer Hall, Sacramento, California 95819 (United States); Norman, Julia E., E-mail: jnorman@usgs.gov [USGS, 2130 SW 5th Avenue, Portland, Oregon 97201 (United States); Scott, Jonathon C., E-mail: jon@usgs.gov [USGS, 202 NW 66th Street, Oklahoma City, Oklahoma 73116 (United States)

2012-08-01

Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources. - Highlights: Black-Right-Pointing-Pointer We assessed mixtures in untreated groundwater samples from public

Brand switching and toxic chemicals in cigarette smoke: A national study.

Directory of Open Access Journals (Sweden)

Jennifer R Mendel

Full Text Available US law requires disclosure of quantities of toxic chemicals (constituents in cigarette smoke by brand and sub-brand. This information may drive smokers to switch to cigarettes with lower chemical quantities, under the misperception that doing so can reduce health risk. We sought to understand past brand-switching behavior and whether learning about specific chemicals in cigarette smoke increases susceptibility to brand switching.Participants were US adult smokers surveyed by phone (n = 1,151, probability sample and online (n = 1,561, convenience sample. Surveys assessed whether smokers had ever switched cigarette brands or styles to reduce health risk and about likelihood of switching if the smoker learned their brand had more of a specific chemical than other cigarettes. Chemicals presented were nicotine, carbon monoxide, lead, formaldehyde, arsenic, and ammonia.Past brand switching to reduce health risk was common among smokers (43% in phone survey, 28% in online survey. Smokers who were female, over 25, and current "light" cigarette users were more likely to have switched brands to reduce health risks (all p < .05. Overall, 61-92% of smokers were susceptible to brand switching based on information about particular chemicals. In both samples, lead, formaldehyde, arsenic, and ammonia led to more susceptibility to switch than nicotine (all p < .05.Many US smokers have switched brands or styles to reduce health risks. The majority said they might or would definitely switch brands if they learned their cigarettes had more of a toxic chemical than other brands. Brand switching is a probable unintended consequence of communications that show differences in smoke chemicals between brands.

Management of evacuation in case of fire accidents in chemical industrial areas

International Nuclear Information System (INIS)

Reniers, G.L.L.; Pauwels, N.; Audenaert, A.; Ale, B.J.M.; Soudan, K.

2007-01-01

Trade-offs between economic and safety arguments exist in the operation of chemical installations, should knock-on calamities induced by fire accidents occur: a sudden installation shutdown might result in substantial economic losses, but may be needed to ensure safety. Due to the very rare nature of domino effect risks induced decision problems an adequate evacuation decision aid model to be used by plant safety management does, to the best of the authors' knowledge, not exist. This paper develops a tentative approach to calculate the economic gains and/or losses linked to the decision problem whether or not, and when, to evacuate chemical installation(s) threatened by possible domino effect risks. The proposed model is illustrated by a case-study based on empirical data

Predicting acute aquatic toxicity of structurally diverse chemicals in fish using artificial intelligence approaches.

Science.gov (United States)

Singh, Kunwar P; Gupta, Shikha; Rai, Premanjali

2013-09-01

The research aims to develop global modeling tools capable of categorizing structurally diverse chemicals in various toxicity classes according to the EEC and European Community directives, and to predict their acute toxicity in fathead minnow using set of selected molecular descriptors. Accordingly, artificial intelligence approach based classification and regression models, such as probabilistic neural networks (PNN), generalized regression neural networks (GRNN), multilayer perceptron neural network (MLPN), radial basis function neural network (RBFN), support vector machines (SVM), gene expression programming (GEP), and decision tree (DT) were constructed using the experimental toxicity data. Diversity and non-linearity in the chemicals' data were tested using the Tanimoto similarity index and Brock-Dechert-Scheinkman statistics. Predictive and generalization abilities of various models constructed here were compared using several statistical parameters. PNN and GRNN models performed relatively better than MLPN, RBFN, SVM, GEP, and DT. Both in two and four category classifications, PNN yielded a considerably high accuracy of classification in training (95.85 percent and 90.07 percent) and validation data (91.30 percent and 86.96 percent), respectively. GRNN rendered a high correlation between the measured and model predicted -log LC50 values both for the training (0.929) and validation (0.910) data and low prediction errors (RMSE) of 0.52 and 0.49 for two sets. Efficiency of the selected PNN and GRNN models in predicting acute toxicity of new chemicals was adequately validated using external datasets of different fish species (fathead minnow, bluegill, trout, and guppy). The PNN and GRNN models showed good predictive and generalization abilities and can be used as tools for predicting toxicities of structurally diverse chemical compounds. Copyright © 2013 Elsevier Inc. All rights reserved.

Toxicity testing of chemical mixtures: some general aspects and need of international guidelines.

Science.gov (United States)

Kappus, H; Yang, R S

1996-01-01

The topics discussed by the Working Group on Toxicity Testing of Chemical Mixtures included the following (1) the study designs and results from two real-life exposure scenarios as additional information to the various investigations reported at the conference; (2) the need to take into consideration low-level, long-term exposure (i.e. mimicking human exposure conditions) as well as the issue of limited resources in experimental toxicology studies; (3) the importance of exploring alternative and predictive toxicology methodologies to minimize animal use and to conserve resources; (4) the realization that interactive toxicity should include the consideration of physical and biological agents in addition to chemicals. Two specific studies reported at the conference were also discussed. A number of recommendations were made concerning the planning and implementation of toxicology studies on chemical mixtures.

Particle size: a missing factor in risk assessment of human exposure to toxic chemicals in settled indoor dust.

Science.gov (United States)

Cao, Zhi-Guo; Yu, Gang; Chen, Yong-Shan; Cao, Qi-Ming; Fiedler, Heidelore; Deng, Shu-Bo; Huang, Jun; Wang, Bin

2012-11-15

For researches on toxic chemicals in settled indoor dust, selection of dust fraction is a critical influencing factor to the accuracy of human exposure risk assessment results. However, analysis of the selection of dust fraction in recent studies revealed that there is no consensus. This study classified and presented researches on distribution of toxic chemicals according to dust particle size and on relationship between dust particle size and human exposure possibility. According to the literature, beyond the fact that there were no consistent conclusions on particle size distribution of adherent fraction, dust with particle size less than 100 μm should be paid more attention and that larger than 250 μm is neither adherent nor proper for human exposure risk assessment. Calculation results based on literature data show that with different selections of dust fractions, analytical results of toxic chemicals would vary up to 10-fold, which means that selecting dust fractions arbitrarily will lead to large errors in risk assessment of human exposure to toxic chemicals in settled dust. Taking into account the influence of dust particle size on risk assessment of human exposure to toxic chemicals, a new methodology for risk assessment of human exposure to toxic chemicals in settled indoor dust is proposed and human exposure parameter systems to settled indoor dust are advised to be established at national and regional scales all over the world. Copyright © 2012 Elsevier Ltd. All rights reserved.

Chemical mixtures in untreated water from public-supply wells in the U.S. — Occurrence, composition, and potential toxicity

International Nuclear Information System (INIS)

Toccalino, Patricia L.; Norman, Julia E.; Scott, Jonathon C.

2012-01-01

Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources. - Highlights: ► We assessed mixtures in untreated groundwater samples from public-supply wells. ► A screening

Characterization of ZnS thin films synthesized through a non-toxic precursors chemical bath

Energy Technology Data Exchange (ETDEWEB)

Rodríguez, C.A. [Department of Materials Engineering, Faculty of Engineering, University of Concepción, Edmundo Larenas 270, Concepción 4070409 (Chile); Sandoval-Paz, M.G. [Department of Physics, Faculty of Physics and Mathematics, University of Concepción, Concepción (Chile); Cabello, G. [Department of Basic Sciences, Faculty of Sciences, University of Bío-Bío, Campus Fernando May, Chillán (Chile); Flores, M.; Fernández, H. [Department of Physics, Faculty of Physics and Mathematics, University of Chile, Beauchef 850, Santiago (Chile); Carrasco, C., E-mail: ccarrascoc@udec.cl [Department of Materials Engineering, Faculty of Engineering, University of Concepción, Edmundo Larenas 270, Concepción 4070409 (Chile)

2014-12-15

Highlights: • High quality ZnS thin films have been deposited by chemical bath deposition technique from a non-toxic precursor’s solution. • Nanocrystalline ZnS thin films with large band gap energy were synthesized without using ammonia. • Evidence that the growing of the thin films is carried out by means of hydroxide mechanism was found. • The properties of these ZnS thin films are similar and in some cases better than the corresponding ones produced using toxic precursors such as ammonia. - Abstract: In solar cells, ZnS window layer deposited by chemical bath technique can reach the highest conversion efficiency; however, precursors used in the process normally are materials highly volatile, toxic and harmful to the environment and health (typically ammonia and hydrazine). In this work the characterization of ZnS thin films deposited by chemical bath in a non-toxic alkaline solution is reported. The effect of deposition technique (growth in several times) on the properties of the ZnS thin film was studied. The films exhibited a high percentage of optical transmission (greater than 80%); as the deposition time increased a decreasing in the band gap values from 3.83 eV to 3.71 eV was observed. From chemical analysis, the presence of ZnS and Zn(OH){sub 2} was identified and X-ray diffraction patterns exhibited a clear peak corresponding to ZnS hexagonal phase (1 0 3) plane, which was confirmed by electron diffraction patterns. From morphological studies, compact samples with well-defined particles, low roughness, homogeneous and pinhole-free in the surface were observed. From obtained results, it is evident that deposits of ZnS–CBD using a non-toxic solution are suitable as window layer for TFSC.

Assessment of the chemical toxicity of long-lived radionuclides on the basis of Who guidelines for drinking-water quality

International Nuclear Information System (INIS)

Renaud-Salis, V.; Menetrier, F.; Leudet, A.; Flury-Herard, A.

2003-01-01

The current assessment of health risks related to long lived radionuclides waste management is not complete if accounting only for radiological toxicity aspects. Although such an approach is justified for a large number of radionuclides of concern, it nevertheless cannot be exclusive and generalised: the chemical toxicity should be considered for radionuclides with a radioactive half-life exceeding 10 5 years. When assessing the chemical or radiological toxicity of a radionuclide, a reference dose applied to drinking water consumption (0.1 mSv/year) can be compared to existing toxicological data. Such an approach has been used by the World Health Organization for natural uranium, for which a guideline value in drinking water derived from its chemical toxicity (2 μg/l) is recommended. WHO's approach is used here for illustrating that the potential chemical toxicity of an element is to be considered for assessing health risks related to long-lived radionuclides. (authors)

CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX

Science.gov (United States)

The increasing density of golf courses represents a potential source of contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to compare the concentrations of contaminants and toxicities of sedime...

Passive dosing of polycyclic aromatic hydrocarbon (PAH) mixtures to terrestrial springtails: Linking mixture toxicity to chemical activities, equilibrium lipid concentrations, and toxic units

DEFF Research Database (Denmark)

Schmidt, Stine Nørgaard; Holmstrup, Martin; Smith, Kilian E. C.

2013-01-01

treatments, containing the polycyclic aromatic hydrocarbons (PAHs) naphthalene, phenanthrene, and pyrene. Springtail lethality was then linked to sum chemical activities (∑a), sum equilibrium lipid concentrations (∑Clipid eq.), and sum toxic units (∑TU). In each case, the effects of all 12 mixture treatments...... could be fitted to one sigmoidal exposure-response relationship. The effective lethal chemical activity (La50) of 0.027 was well within the expected range for baseline toxicity of 0.01-0.1. Linking the effects to the lipid-based exposure parameter yielded an effective lethal concentration (LClipid eq...

Mobility and Attenuation Dynamics of Potentially Toxic Chemical Species at an Abandoned Copper Mine Tailings Dump

Directory of Open Access Journals (Sweden)

Wilson Mugera Gitari

2018-02-01

Full Text Available Large volumes of disposed mine tailings abound in several regions of South Africa, as a consequence of unregulated, unsustainable long years of mining activities. Tailings dumps occupy a large volume of valuable land, and present a potential risk for aquatic systems, through leaching of potentially toxic chemical species. This paper reports on the evaluation of the geochemical processes controlling the mobility of potentially toxic chemical species within the tailings profile, and their potential risk with regard to surface and groundwater systems. Combination of X-ray fluorescence (XRF, X-ray diffraction (XRD, and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS techniques, show that the tailing profiles are uniform, weakly altered, and vary slightly with depth in both physical and geochemical properties, as well as mineralogical composition. Mineralogical analysis showed the following order of abundance: quartz > epidote > chlorite > muscovite > calcite > hematite within the tailings profiles. The neutralization of the dominant alumino-silicate minerals and the absence of sulfidic minerals, have produced medium alkaline pH conditions (7.97–8.37 at all depths and low concentrations of dissolved Cu (20.21–47.9 µg/L, Zn (0.88–1.80 µg/L, Pb (0.27–0.34 µg/L, and SO42− (15.71–55.94 mg/L in the tailings profile leachates. The relative percentage leach for the potentially toxic chemical species was low in the aqueous phase (Ni 0.081%, Cu 0.006%, and Zn 0.05%. This indicates that the transport load of potentially toxic chemical species from tailings to the aqueous phase is very low. The precipitation of secondary hematite has an important known ability to trap and attenuate the mobility of potentially toxic chemical species (Cu, Zn, and Pb by adsorption on the surface area. Geochemical modelling MINTEQA2 showed that the tailings leachates were below saturation regarding oxyhydroxide minerals, but oversaturated with Cu

Comparison of toxicity of class-based organic chemicals to algae and fish based on discrimination of excess toxicity from baseline level.

Science.gov (United States)

Li, Jin J; Tai, Hong W; Yu, Yang; Wen, Yang; Wang, Xiao H; Zhao, Yuan H

2015-07-01

Toxicity data to fish and algae were used to investigate excess toxicity between species. Results show that chemicals exhibiting excess toxicity to fish also show excess toxicity to algae for most of the compounds. This indicates that they share the same mode of action between species. Similar relationships between logKOW and toxicities to fish and algae for baseline and less inert compounds suggest that they have similar critical body residues in the two species. Differences in excess toxicity for some compounds suggest that there is a difference of physiological structure and metabolism between fish and algae. Some reactive compounds (e.g. polyamines) exhibit greater toxic effects for algae than those for fish because of relatively low bio-uptake potential of these hydrophilic compounds in fish as compared with that in algae. Esters exhibiting greater toxicity in fish than that in algae indicate that metabolism can affect the discrimination of excess toxicity from baseline level. Algae growth inhibition is a very good surrogate for fish lethality. This is not only because overall toxicity sensitivity to algae is greater than that to fish, but also the excess toxicity calculated from algal toxicity can better reflect reactivity of compounds with target molecules than fish toxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessment of chemical loadings to Newark Bay, New Jersey from petroleum and hazardous chemical accidents occurring from 1986 to 1991

International Nuclear Information System (INIS)

Gunster, D.G.; Bonnevie, N.L.; Gillis, C.A.; Wenning, R.J.

1993-01-01

Newark Bay, New Jersey, is particularly vulnerable to ecological damage from accidental petroleum and chemical spills due to the enclosed nature of the bay and the large volume of chemical and petroleum commerce within the region. A review of the New Jersey Department of Environmental Protection and Energy's database of hazardous chemical spills in New Jersey waterways was conducted to determine the frequency and volume of chemical and petroleum spills in Newark Bay and its major tributaries. Accidents reported from 1986 to 1991 were extracted from the database and summarized. The compilation of records indicated that 1400 incidents, resulting in the release of more than 18 million gallons of hazardous materials to the estuary had been reported to state officials. The bulk of the chemicals released to the aquatic environment were petroleum products, specifically No. 2 Fuel Oil (4,636,512 gallons) and No. 6 Fuel Oil (12,600,683 gallons). The majority of the reported incidents occurred in the Arthur Kill and its tributaries. The results indicate that accidental discharge of petroleum and other hazardous chemicals to Newark Bay represents a significant ongoing source of chemical pollution

Passive dosing of polycyclic aromatic hydrocarbon (PAH) mixtures to terrestrial springtails: linking mixture toxicity to chemical activities, equilibrium lipid concentrations, and toxic units.

Science.gov (United States)

Schmidt, Stine N; Holmstrup, Martin; Smith, Kilian E C; Mayer, Philipp

2013-07-02

A 7-day mixture toxicity experiment with the terrestrial springtail Folsomia candida was conducted, and the effects were linked to three different mixture exposure parameters. Passive dosing from silicone was applied to tightly control exposure levels and compositions of 12 mixture treatments, containing the polycyclic aromatic hydrocarbons (PAHs) naphthalene, phenanthrene, and pyrene. Springtail lethality was then linked to sum chemical activities (∑a), sum equilibrium lipid concentrations (∑C(lipid eq.)), and sum toxic units (∑TU). In each case, the effects of all 12 mixture treatments could be fitted to one sigmoidal exposure-response relationship. The effective lethal chemical activity (La50) of 0.027 was well within the expected range for baseline toxicity of 0.01-0.1. Linking the effects to the lipid-based exposure parameter yielded an effective lethal concentration (LC(lipid eq 50)) of 133 mmol kg(-1) lipid in good correspondence with the lethal membrane burden for baseline toxicity (40-160 mmol kg(-1) lipid). Finally, the effective lethal toxic unit (LTU50) of 1.20 was rather close to the expected value of 1. Altogether, passive dosing provided tightly controlled mixture exposure in terms of both level and composition, while ∑a, ∑C(lipid eq.), and ∑TU allowed baseline toxicity to be linked to mixture exposure.

Reactive formulations for a neutralization of toxic industrial chemicals

Science.gov (United States)

Tucker, Mark D [Albuqueruqe, NM; Betty, Rita G [Rio Rancho, NM

2006-10-24

Decontamination formulations for neutralization of toxic industrial chemicals, and methods of making and using same. The formulations are effective for neutralizing malathion, hydrogen cyanide, sodium cyanide, butyl isocyanate, carbon disulfide, phosgene gas, capsaicin in commercial pepper spray, chlorine gas, anhydrous ammonia gas; and may be effective at neutralizing hydrogen sulfide, sulfur dioxide, formaldehyde, ethylene oxide, methyl bromide, boron trichloride, fluorine, tetraethyl pyrophosphate, phosphorous trichloride, arsine, and tungsten hexafluoride.

Mode of Action Frameworks in Toxicity Testing and Chemical Risk Assessment

NARCIS (Netherlands)

Meek, B.

2009-01-01

Recently, legislative mandates worldwide are requiring systematic consideration of much larger numbers of chemicals. This necessitates more efficient and effective toxicity testing, as a basis to be more predictive in a risk assessment context. This in turn requires much more emphasis early in the

Chemical mixtures in untreated water from public-supply wells in the U.S.--occurrence, composition, and potential toxicity.

Science.gov (United States)

Toccalino, Patricia L; Norman, Julia E; Scott, Jonathon C

2012-08-01

Chemical mixtures are prevalent in groundwater used for public water supply, but little is known about their potential health effects. As part of a large-scale ambient groundwater study, we evaluated chemical mixtures across multiple chemical classes, and included more chemical contaminants than in previous studies of mixtures in public-supply wells. We (1) assessed the occurrence of chemical mixtures in untreated source-water samples from public-supply wells, (2) determined the composition of the most frequently occurring mixtures, and (3) characterized the potential toxicity of mixtures using a new screening approach. The U.S. Geological Survey collected one untreated water sample from each of 383 public wells distributed across 35 states, and analyzed the samples for as many as 91 chemical contaminants. Concentrations of mixture components were compared to individual human-health benchmarks; the potential toxicity of mixtures was characterized by addition of benchmark-normalized component concentrations. Most samples (84%) contained mixtures of two or more contaminants, each at concentrations greater than one-tenth of individual benchmarks. The chemical mixtures that most frequently occurred and had the greatest potential toxicity primarily were composed of trace elements (including arsenic, strontium, or uranium), radon, or nitrate. Herbicides, disinfection by-products, and solvents were the most common organic contaminants in mixtures. The sum of benchmark-normalized concentrations was greater than 1 for 58% of samples, suggesting that there could be potential for mixtures toxicity in more than half of the public-well samples. Our findings can be used to help set priorities for groundwater monitoring and suggest future research directions for drinking-water treatment studies and for toxicity assessments of chemical mixtures in water resources. Published by Elsevier B.V.

Aquatic toxicity testing of liquid hydrophobic chemicals – Passive dosing exactly at the saturation limit

DEFF Research Database (Denmark)

Stibany, Felix; Nørgaard Schmidt, Stine; Schäffer, Andreas

2017-01-01

The aims of the present study were (1) to develop a passive dosing approach for aquatic toxicity testing of liquid substances with very high Kow values and (2) to apply this approach to the model substance dodecylbenzene (DDB, Log Kow = 8.65). The first step was to design a new passive dosing...... format for testing DDB exactly at its saturation limit. Silicone O-rings were saturated by direct immersion in pure liquid DDB, which resulted in swelling of >14%. These saturated O-rings were used to establish and maintain DDB exposure exactly at the saturation limit throughout 72-h algal growth...... at chemical activity of unity was higher than expected relative to a reported hydrophobicity cut-off in toxicity, but lower than expected relative to a reported chemical activity range for baseline toxicity. The present study introduces a new effective approach for toxicity testing of an important group...

Allium-test as a tool for toxicity testing of environmental radioactive-chemical mixtures

Science.gov (United States)

Oudalova, A. A.; Geras'kin, S. A.; Dikareva, N. S.; Pyatkova, S. V.

2017-01-01

Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium-test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium-test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds.

UTMTOX, Toxic Chemical Transport in Atmosphere, Ground Water, Sediments

International Nuclear Information System (INIS)

1988-01-01

A - Description of program or function: UTMTOX is a unified transport model for toxic materials. It combines hydrologic, atmospheric, and sediment transport in one computer code and extends the scope to predict the transport of not only trace metals but also many chemical compounds, including organics. UTMTOX is capable of calculating 1) the atmospheric dispersion of up to 20 chemicals from a maximum of 10 point, 10 line, and 10 area sources; 2) deposition of one chemical at a time in both wet and dry form on foliage or the surface of the earth; 3) surface flow and erosion; 4) percolation through the soil to a stream channel; and 5) flow in the stream channel to the outfall of a watershed. B - Method of solution: UTMTOX calculates rates of flux of chemicals from release to the atmosphere, through deposition on a watershed, infiltration, and runoff from the soil to flow in the stream channel and the associated sediment transport. From these values, mass balances can be established, budgets for the chemical can be made, and concentrations in many environmental compartments can be estimated. Since the coupling is established among three major submodels, they can share data

Protecting children from toxic chemicals: putting it on Australia's public health agenda.

Science.gov (United States)

Lantz, Sarah

2013-11-01

The high volume and widespread use of industrial chemicals, the backlog of internationally untested chemicals, the uptake of synthetic chemicals found in babies in utero, cord blood, and in breast milk, and the lack of a unified and comprehensive regulatory framework all necessitate developing policies that protect the most vulnerable in our society - our children. Australia's failure to do so raises profound intergenerational ethical issues. This article tells a story of international policy, and where Australia is falling down. It demonstrates that we can learn from countries already taking critical steps to reduce the toxic chemical exposure, and that the development of a comprehensive, child-centered chemical regulation framework is central to turning around Australia's failure.

Safety distance assessment of industrial toxic releases based on frequency and consequence: A case study in Shanghai, China

International Nuclear Information System (INIS)

Yu, Q.; Zhang, Y.; Wang, X.; Ma, W.C.; Chen, L.M.

2009-01-01

A case study on the safety distance assessment of a chemical industry park in Shanghai, China, is presented in this paper. Toxic releases were taken into consideration. A safety criterion based on frequency and consequence of major hazard accidents was set up for consequence analysis. The exposure limits for the accidents with the frequency of more than 10 -4 , 10 -5 -10 -4 and 10 -6 -10 -5 per year were mortalities of 1% (or SLOT), 50% (SLOD) and 75% (twice of SLOD) respectively. Accidents with the frequency of less than 10 -6 per year were considered incredible and ignored in the consequence analysis. Taking the safety distance of all the hazard installations in a chemical plant into consideration, the results based on the new criterion were almost smaller than those based on LC50 or SLOD. The combination of the consequence and risk based results indicated that the hazard installations in two of the chemical plants may be dangerous to the protection targets and measurements had to be taken to reduce the risk. The case study showed that taking account of the frequency of occurrence in the consequence analysis would give more feasible safety distances for major hazard accidents and the results were more comparable to those calculated by risk assessment.

Probabilistic consequence model of accidenal or intentional chemical releases.

Energy Technology Data Exchange (ETDEWEB)

Chang, Y.-S.; Samsa, M. E.; Folga, S. M.; Hartmann, H. M.

2008-06-02

In this work, general methodologies for evaluating the impacts of large-scale toxic chemical releases are proposed. The potential numbers of injuries and fatalities, the numbers of hospital beds, and the geographical areas rendered unusable during and some time after the occurrence and passage of a toxic plume are estimated on a probabilistic basis. To arrive at these estimates, historical accidental release data, maximum stored volumes, and meteorological data were used as inputs into the SLAB accidental chemical release model. Toxic gas footprints from the model were overlaid onto detailed population and hospital distribution data for a given region to estimate potential impacts. Output results are in the form of a generic statistical distribution of injuries and fatalities associated with specific toxic chemicals and regions of the United States. In addition, indoor hazards were estimated, so the model can provide contingency plans for either shelter-in-place or evacuation when an accident occurs. The stochastic distributions of injuries and fatalities are being used in a U.S. Department of Homeland Security-sponsored decision support system as source terms for a Monte Carlo simulation that evaluates potential measures for mitigating terrorist threats. This information can also be used to support the formulation of evacuation plans and to estimate damage and cleanup costs.

Toxic effects of the interaction of titanium dioxide nanoparticles with chemicals or physical factors

Science.gov (United States)

Liu, Kui; Lin, Xialu; Zhao, Jinshun

2013-01-01

Due to their chemical stability and nonallergic, nonirritant, and ultraviolet protective properties, titanium dioxide (TiO2) nanoparticles (NPs) have been widely used in industries such as electronics, optics, and material sciences, as well as architecture, medicine, and pharmacology. However, increasing concerns have been raised in regards to its ecotoxicity and toxicity on the aquatic environment as well as to humans. Although insights have been gained into the effects of TiO2 NPs on susceptible biological systems, there is still much ground to be covered, particularly in respect of our knowledge of the effects of the interaction of TiO2 NPs with other chemicals or physical factors. Studies suggest that interactions of TiO2 NPs with other chemicals or physical factors may result in an increase in toxicity or adverse effects. This review highlights recent progress in the study of the interactive effects of TiO2 NPs with other chemicals or physical factors. PMID:23901269

1997 toxic chemical release inventory. Emergency Planning and Community Right-To-Know Act, Section 313

International Nuclear Information System (INIS)

Zaloudek, D.E.

1998-01-01

Two listed toxic chemicals were used at the Hanford Site above established activity thresholds: phosphoric acid and chlorine. Because total combined quantities of chlorine released, disposed, treated, recovered through recycle operations, co-combusted for energy recovery, and transferred to off-site locations for the purpose of recycle, energy recovery, treatment, and/or disposal, amounted to less than 500 pounds, the Hanford Site qualified for the alternate one million pound threshold for chlorine. Accordingly, this Toxic Chemical Release Inventory includes a Form A for chlorine, and a Form B for phosphoric acid

Predicting the formation and the dispersion of toxic combustion products from the fires of dangerous substances

Science.gov (United States)

Nevrlý, V.; Bitala, P.; Danihelka, P.; Dobeš, P.; Dlabka, J.; Hejzlar, T.; Baudišová, B.; Míček, D.; Zelinger, Z.

2012-04-01

Natural events, such as wildfires, lightning or earthquakes represent a frequent trigger of industrial fires involving dangerous substances. Dispersion of smoke plume from such fires and the effects of toxic combustion products are one of the reference scenarios expected in the framework of major accident prevention. Nowadays, tools for impact assessment of these events are rather missing. Detailed knowledge of burning material composition, atmospheric conditions, and other factors are required in order to describe quantitatively the source term of toxic fire products and to evaluate the parameters of smoke plume. Nevertheless, an assessment of toxic emissions from large scale fires involves a high degree of uncertainty, because of the complex character of physical and chemical processes in the harsh environment of uncontrolled flame. Among the others, soot particle formation can be mentioned as still being one of the unresolved problems in combustion chemistry, as well as decomposition pathways of chemical substances. Therefore, simplified approach for estimating the emission factors from outdoor fires of dangerous chemicals, utilizable for major accident prevention and preparedness, was developed and the case study illustrating the application of the proposed method was performed. ALOFT-FT software tool based on large eddy simulation of buoyant fire plumes was employed for predicting the local toxic contamination in the down-wind vicinity of the fire. The database of model input parameters can be effectively modified enabling the simulation of the smoke plume from pool fires or jet fires of arbitrary flammable (or combustible) gas, liquid or solid. This work was supported by the Ministry of Education, Youth and Sports of the Czech Republic via the project LD11012 (in the frame of the COST CM0901 Action) and the Ministry of Environment of the Czech Republic (project no. SPII 1a10 45/70).

Fate of chemical warfare agents and toxic industrial chemicals in landfills.

Science.gov (United States)

Bartelt-Hunt, Shannon L; Barlaz, Morton A; Knappe, Detlef R U; Kjeldsen, Peter

2006-07-01

One component of preparedness for a chemical attack is planning for the disposal of contaminated debris. To assess the feasibility of contaminated debris disposal in municipal solid waste (MSW) landfills, the fate of selected chemical warfare agents (CWAs) and toxic industrial chemicals (TICs) in MSW landfills was predicted with a mathematical model. Five blister agents [sulfur mustard (HD), nitrogen mustard (HN-2), lewisite (L), ethyldichloroarsine (ED), and phosgene oxime (CX)], eight nerve agents [tabun (GA), sarin (GB), soman (GD), GE, GF, VX, VG, and VM], one riot-control agent [CS], and two TICs [furan and carbon disulfide] were studied. The effects of both infiltration (climate) and contaminant biodegradability on fate predictions were assessed. Model results showed that hydrolysis and gas-phase advection were the principal fate pathways for CWAs and TICs, respectively. Apart from CX and the TICs, none of the investigated compounds was predicted to persist in a landfill for more than 5 years. Climate had little impact on CWA/TIC fate, and biodegradability was only important for compounds with long hydrolysis half-lives. Monte Carlo simulations were performed to assess the influence of uncertainty in model input parameters on CWA/TIC fate predictions. Correlation analyses showed that uncertainty in hydrolysis rate constants was the primary contributor to variance of CWA fate predictions, while uncertainty in the Henry's Law constant and landfill gas-production rate accounted for most of the variance of TIC fate predictions. CWA hydrolysates were more persistent than the parent CWAs, but limited information is available on abiotic or biotic transformation rates for these chemicals.

Low-toxic and safe nanomaterials by surface-chemical design, carbon nanotubes, fullerenes, metallofullerenes, and graphenes

Science.gov (United States)

YanEqual Contribution, Liang; Zhao, Feng; Li, Shoujian; Hu, Zhongbo; Zhao, Yuliang

2011-02-01

The toxicity grade for a bulk material can be approximately determined by three factors (chemical composition, dose, and exposure route). However, for a nanomaterial it depends on more than ten factors. Interestingly, some nano-factors (like huge surface adsorbability, small size, etc.) that endow nanomaterials with new biomedical functions are also potential causes leading to toxicity or damage to the living organism. Is it possible to create safe nanomaterials if such a number of complicated factors need to be regulated? We herein try to find answers to this important question. We first discuss chemical processes that are applicable for nanosurface modifications, in order to improve biocompatibility, regulate ADME, and reduce the toxicity of carbon nanomaterials (carbon nanotubes, fullerenes, metallofullerenes, and graphenes). Then the biological/toxicological effects of surface-modified and unmodified carbon nanomaterials are comparatively discussed from two aspects: the lowered toxic responses or the enhanced biomedical functions. We summarize the eight biggest challenges in creating low-toxicity and safer nanomaterials and some significant topics of future research needs: to find out safer nanofactors; to establish controllable surface modifications and simpler chemistries for low-toxic nanomaterials; to explore the nanotoxicity mechanisms; to justify the validity of current toxicological theories in nanotoxicology; to create standardized nanomaterials for toxicity tests; to build theoretical models for cellular and molecular interactions of nanoparticles; and to establish systematical knowledge frameworks for nanotoxicology.

In silico toxicology: comprehensive benchmarking of multi-label classification methods applied to chemical toxicity data

KAUST Repository

Raies, Arwa B.

2017-12-05

One goal of toxicity testing, among others, is identifying harmful effects of chemicals. Given the high demand for toxicity tests, it is necessary to conduct these tests for multiple toxicity endpoints for the same compound. Current computational toxicology methods aim at developing models mainly to predict a single toxicity endpoint. When chemicals cause several toxicity effects, one model is generated to predict toxicity for each endpoint, which can be labor and computationally intensive when the number of toxicity endpoints is large. Additionally, this approach does not take into consideration possible correlation between the endpoints. Therefore, there has been a recent shift in computational toxicity studies toward generating predictive models able to predict several toxicity endpoints by utilizing correlations between these endpoints. Applying such correlations jointly with compounds\\' features may improve model\\'s performance and reduce the number of required models. This can be achieved through multi-label classification methods. These methods have not undergone comprehensive benchmarking in the domain of predictive toxicology. Therefore, we performed extensive benchmarking and analysis of over 19,000 multi-label classification models generated using combinations of the state-of-the-art methods. The methods have been evaluated from different perspectives using various metrics to assess their effectiveness. We were able to illustrate variability in the performance of the methods under several conditions. This review will help researchers to select the most suitable method for the problem at hand and provide a baseline for evaluating new approaches. Based on this analysis, we provided recommendations for potential future directions in this area.

In silico toxicology: comprehensive benchmarking of multi-label classification methods applied to chemical toxicity data

KAUST Repository

Raies, Arwa B.; Bajic, Vladimir B.

2017-01-01

One goal of toxicity testing, among others, is identifying harmful effects of chemicals. Given the high demand for toxicity tests, it is necessary to conduct these tests for multiple toxicity endpoints for the same compound. Current computational toxicology methods aim at developing models mainly to predict a single toxicity endpoint. When chemicals cause several toxicity effects, one model is generated to predict toxicity for each endpoint, which can be labor and computationally intensive when the number of toxicity endpoints is large. Additionally, this approach does not take into consideration possible correlation between the endpoints. Therefore, there has been a recent shift in computational toxicity studies toward generating predictive models able to predict several toxicity endpoints by utilizing correlations between these endpoints. Applying such correlations jointly with compounds' features may improve model's performance and reduce the number of required models. This can be achieved through multi-label classification methods. These methods have not undergone comprehensive benchmarking in the domain of predictive toxicology. Therefore, we performed extensive benchmarking and analysis of over 19,000 multi-label classification models generated using combinations of the state-of-the-art methods. The methods have been evaluated from different perspectives using various metrics to assess their effectiveness. We were able to illustrate variability in the performance of the methods under several conditions. This review will help researchers to select the most suitable method for the problem at hand and provide a baseline for evaluating new approaches. Based on this analysis, we provided recommendations for potential future directions in this area.

1992 Toxic Chemical Release Inventory: Emergency Planning and Community Right-To-Know-Act of 1986 Section 313

International Nuclear Information System (INIS)

1993-07-01

Section 313 of the Emergency Planning and Community Right-To-Know Act of 1986 (EPCRA) requires the annual submittal of toxic chemical release information to the US Environmental Protection Agency (EPA). The following document is the July 1993 submittal of the EPCRA Toxic Chemical Release Inventory Report (Form R). Included is a Form R for chlorine and for lead, the two chemicals used in excess of the established regulatory thresholds at the Hanford Site by the US Department of Energy, Richland Operations Office and its contractors during calendar year 1992

SEDIMENT CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX.

Science.gov (United States)

The increasing density of golf courses represents a potential source of sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities...

Enhancement of developmental toxicity effects of chemicals by gestational stress. A review

DEFF Research Database (Denmark)

Hougaard, Karin S; Hansen, Åse Marie

2007-01-01

Risk assessment of developmental toxicants is almost exclusively based on single chemicals studied in animals under controlled experimental conditions, as to reduce stress. Although humans may be exposed simultaneously to numerous hazards, little is known about the interaction of prenatal chemica...

Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - summary report

International Nuclear Information System (INIS)

Gerton, R.E.

1997-01-01

This report is a summary of the Accident Investigation Board Report on the May 14, 1997, Chemical Explosion at the Plutonium Reclamation Facility, Hanford Site, Richland, Washington (DOE/RL-97-59). The referenced report provides a greater level of detail and includes a complete discussion of the facts identified, analysis of those facts, conclusions derived from the analysis, identification of the accident's causal factors, and recommendations that should be addressed through follow-up action by the U.S. Department of Energy and its contractors. This companion document provides a concise summary of that report, with emphasis on management issues. Evaluation of emergency and occupational health response to, and radiological and chemical releases from, this accident was not within the scope of this investigation, but is the subject of a separate investigation and report (see DOE/RL-97-62)

1998 Toxic Chemical Release Inventory Report for the Emergency Planning and Community Right-to-Know Act of 1986, Title III

International Nuclear Information System (INIS)

Stockton, Marjorie B.

1999-01-01

The Emergency Planning and Community Right-to-Know Act (EPCRA) of 1986 [also known as the Superfund Amendment and Reauthorization Act (SARA), Title III], as modified by Executive Order 12856, requires that all federal facilities evaluate the need to submit an annual Toxic Chemical Release Inventory report as prescribed in Title III, Section 313 of this Act. This annual report is due every July for the preceding calendar year. Owners and operators who manufacture, process, or otherwise use certain toxic chemicals above listed threshold quantities are required to report their toxic chemical releases to all environmental mediums (air, water, soil, etc.). At Los Alamos National Laboratory (LANL), no EPCRA Section 313 chemicals were used in 1998 above the reportable threshold limits of 10,000 lb or 25,000 lb. Therefore LANL was not required to submit any Toxic Chemical Release Inventory reports (Form Rs) for 1998. This document was prepared to provide a detailed description of the evaluation on chemical usage and EPCRA Section 313 threshold determinations for LANL for 1998

Chemical Compounds Toxic to Invertebrates Isolated from Marine Cyanobacteria of Potential Relevance to the Agricultural Industry

KAUST Repository

Essack, Magbubah

2014-10-29

In spite of advances in invertebrate pest management, the agricultural industry is suffering from impeded pest control exacerbated by global climate changes that have altered rain patterns to favour opportunistic breeding. Thus, novel naturally derived chemical compounds toxic to both terrestrial and aquatic invertebrates are of interest, as potential pesticides. In this regard, marine cyanobacterium-derived metabolites that are toxic to both terrestrial and aquatic invertebrates continue to be a promising, but neglected, source of potential pesticides. A PubMed query combined with hand-curation of the information from retrieved articles allowed for the identification of 36 cyanobacteria-derived chemical compounds experimentally confirmed as being toxic to invertebrates. These compounds are discussed in this review.

Chemical Compounds Toxic to Invertebrates Isolated from Marine Cyanobacteria of Potential Relevance to the Agricultural Industry

KAUST Repository

Essack, Magbubah; Alzubaidy, Hanin S.; Bajic, Vladimir B.; Archer, John A.C.

2014-01-01

In spite of advances in invertebrate pest management, the agricultural industry is suffering from impeded pest control exacerbated by global climate changes that have altered rain patterns to favour opportunistic breeding. Thus, novel naturally derived chemical compounds toxic to both terrestrial and aquatic invertebrates are of interest, as potential pesticides. In this regard, marine cyanobacterium-derived metabolites that are toxic to both terrestrial and aquatic invertebrates continue to be a promising, but neglected, source of potential pesticides. A PubMed query combined with hand-curation of the information from retrieved articles allowed for the identification of 36 cyanobacteria-derived chemical compounds experimentally confirmed as being toxic to invertebrates. These compounds are discussed in this review.

Chemical Compounds Toxic to Invertebrates Isolated from Marine Cyanobacteria of Potential Relevance to the Agricultural Industry

Science.gov (United States)

Essack, Magbubah; Alzubaidy, Hanin S.; Bajic, Vladimir B.; Archer, John A. C.

2014-01-01

In spite of advances in invertebrate pest management, the agricultural industry is suffering from impeded pest control exacerbated by global climate changes that have altered rain patterns to favour opportunistic breeding. Thus, novel naturally derived chemical compounds toxic to both terrestrial and aquatic invertebrates are of interest, as potential pesticides. In this regard, marine cyanobacterium-derived metabolites that are toxic to both terrestrial and aquatic invertebrates continue to be a promising, but neglected, source of potential pesticides. A PubMed query combined with hand-curation of the information from retrieved articles allowed for the identification of 36 cyanobacteria-derived chemical compounds experimentally confirmed as being toxic to invertebrates. These compounds are discussed in this review. PMID:25356733

A high-throughput method for assessing chemical toxicity using a Caenorhabditis elegans reproduction assay

International Nuclear Information System (INIS)

Boyd, Windy A.; McBride, Sandra J.; Rice, Julie R.; Snyder, Daniel W.; Freedman, Jonathan H.

2010-01-01

The National Research Council has outlined the need for non-mammalian toxicological models to test the potential health effects of a large number of chemicals while also reducing the use of traditional animal models. The nematode Caenorhabditis elegans is an attractive alternative model because of its well-characterized and evolutionarily conserved biology, low cost, and ability to be used in high-throughput screening. A high-throughput method is described for quantifying the reproductive capacity of C. elegans exposed to chemicals for 48 h from the last larval stage (L4) to adulthood using a COPAS Biosort. Initially, the effects of exposure conditions that could influence reproduction were defined. Concentrations of DMSO vehicle ≤ 1% did not affect reproduction. Previous studies indicated that C. elegans may be influenced by exposure to low pH conditions. At pHs greater than 4.5, C. elegans reproduction was not affected; however below this pH there was a significant decrease in the number of offspring. Cadmium chloride was chosen as a model toxicant to verify that automated measurements were comparable to those of traditional observational studies. EC 50 values for cadmium for automated measurements (176-192 μM) were comparable to those previously reported for a 72-h exposure using manual counting (151 μM). The toxicity of seven test toxicants on C. elegans reproduction was highly correlative with rodent lethality suggesting that this assay may be useful in predicting the potential toxicity of chemicals in other organisms.

Impact of bioavailability on the correlation between in vitro cytotoxic and in vivo acute fish toxic concentrations of chemicals

International Nuclear Information System (INIS)

Guelden, Michael; Seibert, Hasso

2005-01-01

The lower sensitivity of in vitro cytotoxicity assays currently restricts their use as alternative to the fish acute toxicity assays for hazard assessment of chemicals in the aquatic environment. In vitro cytotoxic potencies mostly refer to nominal concentrations. The main objective of the present study was to investigate, whether a reduced availability of chemicals in vitro can account for the lower sensitivity of in vitro toxicity test systems. For this purpose, the bioavailable free fractions of the nominal cytotoxic concentrations (EC 50 ) of chemicals determined with a cytotoxicity test system using Balb/c 3T3 cells and the corresponding free cytotoxic concentrations (ECu 50 ) were calculated. The algorithm applied is based on a previously developed simple equilibrium distribution model for chemicals in cell cultures with serum-supplemented culture media. This model considers the distribution of chemicals between water, lipids and serum albumin. The algorithm requires the relative lipid volume of the test system, the octanol-water partition coefficient (K ow ) and the in vitro albumin-bound fraction of the chemicals. The latter was determined from EC 50 -measurements in the presence of different albumin concentrations with the Balb/c 3T3 test system. Organic chemicals covering a wide range of cytotoxic potency (EC 50 : 0.16-527000 μM) and lipophilicity (log K ow : -5.0-6.96) were selected, for which fish acute toxicity data (LC 50 -values) from at least one of the three fish species, medaka, rainbow trout and fathead minnow, respectively, were available. The availability of several chemicals was shown to be extensively reduced either by partitioning into lipids or by serum albumin binding, or due to both mechanisms. Reduction of bioavailability became more important with increasing cytotoxic potency. The sensitivity of the Balb/c 3T3 cytotoxicity assay and the correspondence between in vivo and in vitro toxic potencies were increased when the free cytotoxic

Role of environmental stress in the physiological response to chemical toxicants

International Nuclear Information System (INIS)

Gordon, C.J.

2003-01-01

Environmental physiology is the study of the physiological mechanisms that allow animals to cope with and adapt to changes in temperature, humidity, atmospheric pressure, and other natural factors of their physical environment. Nearly all toxicological and pharmacological studies are performed in resting (i.e., non exercising) experimental animals acclimatized to standard environmental conditions that are usually considered ideal to the animal's physiological well-being. These ideal test conditions are clearly not representative of the fluctuations in the natural environment encountered by humans and other animals on a day-to-day basis. It behooves the toxicologist, especially those interested in extrapolating experimental data from laboratory animals to humans, to consider how variations in the natural environment will alter physiological responses to toxicants. Temperature and exercise are the two most well-studied parameters in the fields of environmental physiology and toxicology. In general, high temperatures exacerbate the toxic effects of many environmental toxicants. Moreover, exercising subjects are generally more vulnerable to airborne toxic agents. The prospect of global warming also warrants a better assessment of how higher environmental temperatures may impact on the response of humans and other species to toxic chemicals. Hence, this paper and accompanying papers from the proceedings of a symposium focus on the salient aspects of the interaction between environmental stress and physiological response to toxic agents with particular emphasis on temperature and exercise

Allium -test as a tool for toxicity testing of environmental radioactive-chemical mixtures

International Nuclear Information System (INIS)

Oudalova, A A; Pyatkova, S V; Geras’kin, S A; Dikareva, N S

2017-01-01

Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium -test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium -test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds. (paper)

Toxic release consequence analysis tool (TORCAT) for inherently safer design plant

International Nuclear Information System (INIS)

Shariff, Azmi Mohd; Zaini, Dzulkarnain

2010-01-01

Many major accidents due to toxic release in the past have caused many fatalities such as the tragedy of MIC release in Bhopal, India (1984). One of the approaches is to use inherently safer design technique that utilizes inherent safety principle to eliminate or minimize accidents rather than to control the hazard. This technique is best implemented in preliminary design stage where the consequence of toxic release can be evaluated and necessary design improvements can be implemented to eliminate or minimize the accidents to as low as reasonably practicable (ALARP) without resorting to costly protective system. However, currently there is no commercial tool available that has such capability. This paper reports on the preliminary findings on the development of a prototype tool for consequence analysis and design improvement via inherent safety principle by utilizing an integrated process design simulator with toxic release consequence analysis model. The consequence analysis based on the worst-case scenarios during process flowsheeting stage were conducted as case studies. The preliminary finding shows that toxic release consequences analysis tool (TORCAT) has capability to eliminate or minimize the potential toxic release accidents by adopting the inherent safety principle early in preliminary design stage.

Radiological accidents, scenarios, planning and answers

International Nuclear Information System (INIS)

Solis Delgado, Alexander.

2008-01-01

Radiological accidents, scenarios and the importance of a good planning to prevent and control these types of accidents are presented. The radiation can be only one of the risks in an accident, most of dominant radiological risks are not radiological (fire, toxic gases, etc.). The common causes of radiological accidents, potential risks such as external irradiation, internal contamination and the environment pollution are highlighted. In addition, why accidents happen and how they evolve is explained. It describes some incidents with the radiation occurred in Costa Rica from 1993 to 2007. The coordination of emergency management in Costa Rica in relation to a radiological accident, and some mechanisms of action that have practiced in other places are focuses. Among the final considerations are the need to finalize the national plan for radiological emergencies as a tool of empowerment for the teams of emergency care and the availability of information. Likewise the processes of communication, coordination and cooperation to avoid chaos, confusion and crisis are also highlighted [es

Learning lessons from Natech accidents - the eNATECH accident database

Science.gov (United States)

Krausmann, Elisabeth; Girgin, Serkan

2016-04-01

When natural hazards impact industrial facilities that house or process hazardous materials, fires, explosions and toxic releases can occur. This type of accident is commonly referred to as Natech accident. In order to prevent the recurrence of accidents or to better mitigate their consequences, lessons-learned type studies using available accident data are usually carried out. Through post-accident analysis, conclusions can be drawn on the most common damage and failure modes and hazmat release paths, particularly vulnerable storage and process equipment, and the hazardous materials most commonly involved in these types of accidents. These analyses also lend themselves to identifying technical and organisational risk-reduction measures that require improvement or are missing. Industrial accident databases are commonly used for retrieving sets of Natech accident case histories for further analysis. These databases contain accident data from the open literature, government authorities or in-company sources. The quality of reported information is not uniform and exhibits different levels of detail and accuracy. This is due to the difficulty of finding qualified information sources, especially in situations where accident reporting by the industry or by authorities is not compulsory, e.g. when spill quantities are below the reporting threshold. Data collection has then to rely on voluntary record keeping often by non-experts. The level of detail is particularly non-uniform for Natech accident data depending on whether the consequences of the Natech event were major or minor, and whether comprehensive information was available for reporting. In addition to the reporting bias towards high-consequence events, industrial accident databases frequently lack information on the severity of the triggering natural hazard, as well as on failure modes that led to the hazmat release. This makes it difficult to reconstruct the dynamics of the accident and renders the development of

Relationship between physico-chemical characteristics and potential toxicity of PM10.

Science.gov (United States)

Megido, Laura; Suárez-Peña, Beatriz; Negral, Luis; Castrillón, Leonor; Suárez, Susana; Fernández-Nava, Yolanda; Marañón, Elena

2016-11-01

PM10 was sampled at a suburban location affected by traffic and industry in the north of Spain. The samples were analysed to determine the chemical components of PM10 (organic and elemental carbon, soluble chemical species and metals). The aim of this study was to assess the toxicity of PM10 in terms of the bulk analysis and the physico-chemical properties of the particles. Total carbon, sulphates, ammonium, chlorides and nitrates were found to be the major constituents of PM10. The contribution of the last of these was found to increase significantly with PM10 concentration (Pearson coefficient correlation of 0.7, p-value major risk to human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

40 CFR 68.42 - Five-year accident history.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Five-year accident history. 68.42... (CONTINUED) CHEMICAL ACCIDENT PREVENTION PROVISIONS Hazard Assessment § 68.42 Five-year accident history. (a) The owner or operator shall include in the five-year accident history all accidental releases from...

In silico prediction of Tetrahymena pyriformis toxicity for diverse industrial chemicals with substructure pattern recognition and machine learning methods.

Science.gov (United States)

Cheng, Feixiong; Shen, Jie; Yu, Yue; Li, Weihua; Liu, Guixia; Lee, Philip W; Tang, Yun

2011-03-01

There is an increasing need for the rapid safety assessment of chemicals by both industries and regulatory agencies throughout the world. In silico techniques are practical alternatives in the environmental hazard assessment. It is especially true to address the persistence, bioaccumulative and toxicity potentials of organic chemicals. Tetrahymena pyriformis toxicity is often used as a toxic endpoint. In this study, 1571 diverse unique chemicals were collected from the literature and composed of the largest diverse data set for T. pyriformis toxicity. Classification predictive models of T. pyriformis toxicity were developed by substructure pattern recognition and different machine learning methods, including support vector machine (SVM), C4.5 decision tree, k-nearest neighbors and random forest. The results of a 5-fold cross-validation showed that the SVM method performed better than other algorithms. The overall predictive accuracies of the SVM classification model with radial basis functions kernel was 92.2% for the 5-fold cross-validation and 92.6% for the external validation set, respectively. Furthermore, several representative substructure patterns for characterizing T. pyriformis toxicity were also identified via the information gain analysis methods. Copyright © 2010 Elsevier Ltd. All rights reserved.

Depressurization accident analysis of MPBR by PBRSIM with chemical reaction model

International Nuclear Information System (INIS)

No, Hee Cheon; Kadak, A. C.

2002-01-01

The simple model for natural circulation is implemented into PBR S IM to provide air inlet velocity from the containment air space. For the friction and form loss only the pebble region is considered conservatively modeling laminar flow through a packed bed. For the chemical reaction model of PBR S IM the oxidation rate is determined as the minimum value of three mechanisms estimated at each time step: oxygen mass flow rate entering the bottom of the reflector, oxidation rate by kinetics, and oxygen mass flow rate arriving at the graphite surface by diffusion. Oxygen mass flux arriving at the graphite surface by diffusion is estimated based on energy-mass analogy. Two types of exothermic chemical reaction are considered: (C + zO 2 → xCO + yCO 2 ) and (2CO + O 2 2CO 2 ). The heterogeneous and homogeneous chemical reaction rates by kinetics are determined by INEEL and Bruno correlations, respectively. The instantaneous depressurization accident of MPBR is simulated using PBR S IM with chemical model. The air inlet velocity is initially rapidly dropped within 10 hr and reaches a saturation value of about 1.5cm/s. The oxidation rate by the diffusion process becomes lower than that by the chemical kinetics above 600K. The maximum pebble bed temperatures without and with chemical reaction reach the peak values of 1560 and 1617 .deg. C at 80 hr and 92 hr, respectively. As the averaged temperatures in the bottom reflector and the pebble bed regions increase with time, (C+1/2O2 ->CO) reaction becomes dominant over (C+O 2 →CO 2 ) reaction. Also, the CO generated by (C+1/2O 2 →CO) reaction will be consumed by (2CO+O 2 →2CO 2 ) reaction and the energy homogeneously generated by this CO depletion reaction becomes dominant over the heterogeneous reaction

Adolescent Exposure to Toxic Volatile Organic Chemicals From E-Cigarettes.

Science.gov (United States)

Rubinstein, Mark L; Delucchi, Kevin; Benowitz, Neal L; Ramo, Danielle E

2018-04-01

There is an urgent need to understand the safety of e-cigarettes with adolescents. We sought to identify the presence of chemical toxicants associated with e-cigarette use among adolescents. Adolescent e-cigarette users (≥1 use within the past 30 days, ≥10 lifetime e-cigarette use episodes) were divided into e-cigarette-only users (no cigarettes in the past 30 days, urine 4-[methylnitrosamino]-1-[3-pyridyl]-1-butanol [NNAL] level 30 pg/mL; n = 16), and never-using controls ( N = 20). Saliva was collected within 24 hours of the last e-cigarette use for analysis of cotinine and urine for analysis of NNAL and levels of 8 volatile organic chemical compounds. Bivariate analyses compared e-cigarette-only users with dual users, and regression analyses compared e-cigarette-only users with dual users and controls on levels of toxicants. The participants were 16.4 years old on average. Urine excretion of metabolites of benzene, ethylene oxide, acrylonitrile, acrolein, and acrylamide was significantly higher in dual users versus e-cigarette-only users (all P < .05). Excretion of metabolites of acrylonitrile, acrolein, propylene oxide, acrylamide, and crotonaldehyde were significantly higher in e-cigarette-only users compared with controls (all P < .05). Although e-cigarette vapor may be less hazardous than tobacco smoke, our findings can be used to challenge the idea that e-cigarette vapor is safe, because many of the volatile organic compounds we identified are carcinogenic. Messaging to teenagers should include warnings about the potential risk from toxic exposure to carcinogenic compounds generated by these products. Copyright © 2018 by the American Academy of Pediatrics.

Effects of toxic chemicals on the reproductive system. Council on Scientific Affairs.

Science.gov (United States)

1985-06-21

In an effort to make physicians more aware of the hazards of the workplace to pregnant workers, the Council on Scientific Affairs' Advisory Panel on Reproductive Hazards in the Workplace prepared this third and final report reviewing the effects of chemical exposure. A total of 120 chemicals were considered for reviews based on an estimation of their imminent hazard, ie, widespread use and/or inherent toxicity. Following a brief introduction, which sets out general principles, clinical applications, and aids to the recognition of a human teratogen, the report presents reviews and opinions for three representative chemicals. Information concerning the remaining 117 compounds is available upon request.

Chemical and Plant-Based Insect Repellents: Efficacy, Safety, and Toxicity.

Science.gov (United States)

Diaz, James H

2016-03-01

Most emerging infectious diseases today are arthropod-borne and cannot be prevented by vaccinations. Because insect repellents offer important topical barriers of personal protection from arthropod-borne infectious diseases, the main objectives of this article were to describe the growing threats to public health from emerging arthropod-borne infectious diseases, to define the differences between insect repellents and insecticides, and to compare the efficacies and toxicities of chemical and plant-derived insect repellents. Internet search engines were queried with key words to identify scientific articles on the efficacy, safety, and toxicity of chemical and plant-derived topical insect repellants and insecticides to meet these objectives. Data sources reviewed included case reports; case series; observational, longitudinal, and surveillance studies; and entomological and toxicological studies. Descriptive analysis of the data sources identified the most effective application of insect repellents as a combination of topical chemical repellents, either N-diethyl-3-methylbenzamide (formerly N, N-diethyl-m-toluamide, or DEET) or picaridin, and permethrin-impregnated or other pyrethroid-impregnated clothing over topically treated skin. The insecticide-treated clothing would provide contact-level insecticidal effects and provide better, longer lasting protection against malaria-transmitting mosquitoes and ticks than topical DEET or picaridin alone. In special cases, where environmental exposures to disease-transmitting ticks, biting midges, sandflies, or blackflies are anticipated, topical insect repellents containing IR3535, picaridin, or oil of lemon eucalyptus (p-menthane-3, 8-diol or PMD) would offer better topical protection than topical DEET alone. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Identifying developmental toxicity pathways for a subset of ToxCast chemicals using human embryonic stem cells and metabolomics

Energy Technology Data Exchange (ETDEWEB)

Kleinstreuer, N.C., E-mail: kleinstreuer.nicole@epa.gov [NCCT, US EPA, RTP, NC 27711 (United States); Smith, A.M.; West, P.R.; Conard, K.R.; Fontaine, B.R. [Stemina Biomarker Discovery, Inc., Madison, WI 53719 (United States); Weir-Hauptman, A.M. [Covance, Inc., Madison, WI 53704 (United States); Palmer, J.A. [Stemina Biomarker Discovery, Inc., Madison, WI 53719 (United States); Knudsen, T.B.; Dix, D.J. [NCCT, US EPA, RTP, NC 27711 (United States); Donley, E.L.R. [Stemina Biomarker Discovery, Inc., Madison, WI 53719 (United States); Cezar, G.G. [Stemina Biomarker Discovery, Inc., Madison, WI 53719 (United States); University of Wisconsin-Madison, Madison, WI 53706 (United States)

2011-11-15

Metabolomics analysis was performed on the supernatant of human embryonic stem (hES) cell cultures exposed to a blinded subset of 11 chemicals selected from the chemical library of EPA's ToxCast Trade-Mark-Sign chemical screening and prioritization research project. Metabolites from hES cultures were evaluated for known and novel signatures that may be indicative of developmental toxicity. Significant fold changes in endogenous metabolites were detected for 83 putatively annotated mass features in response to the subset of ToxCast chemicals. The annotations were mapped to specific human metabolic pathways. This revealed strong effects on pathways for nicotinate and nicotinamide metabolism, pantothenate and CoA biosynthesis, glutathione metabolism, and arginine and proline metabolism pathways. Predictivity for adverse outcomes in mammalian prenatal developmental toxicity studies used ToxRefDB and other sources of information, including Stemina Biomarker Discovery's predictive DevTox Registered-Sign model trained on 23 pharmaceutical agents of known developmental toxicity and differing potency. The model initially predicted developmental toxicity from the blinded ToxCast compounds in concordance with animal data with 73% accuracy. Retraining the model with data from the unblinded test compounds at one concentration level increased the predictive accuracy for the remaining concentrations to 83%. These preliminary results on a 11-chemical subset of the ToxCast chemical library indicate that metabolomics analysis of the hES secretome provides information valuable for predictive modeling and mechanistic understanding of mammalian developmental toxicity. -- Highlights: Black-Right-Pointing-Pointer We tested 11 environmental compounds in a hESC metabolomics platform. Black-Right-Pointing-Pointer Significant changes in secreted small molecule metabolites were observed. Black-Right-Pointing-Pointer Perturbed mass features map to pathways critical for normal

Identifying developmental toxicity pathways for a subset of ToxCast chemicals using human embryonic stem cells and metabolomics

International Nuclear Information System (INIS)

Kleinstreuer, N.C.; Smith, A.M.; West, P.R.; Conard, K.R.; Fontaine, B.R.; Weir-Hauptman, A.M.; Palmer, J.A.; Knudsen, T.B.; Dix, D.J.; Donley, E.L.R.; Cezar, G.G.

2011-01-01

Metabolomics analysis was performed on the supernatant of human embryonic stem (hES) cell cultures exposed to a blinded subset of 11 chemicals selected from the chemical library of EPA's ToxCast™ chemical screening and prioritization research project. Metabolites from hES cultures were evaluated for known and novel signatures that may be indicative of developmental toxicity. Significant fold changes in endogenous metabolites were detected for 83 putatively annotated mass features in response to the subset of ToxCast chemicals. The annotations were mapped to specific human metabolic pathways. This revealed strong effects on pathways for nicotinate and nicotinamide metabolism, pantothenate and CoA biosynthesis, glutathione metabolism, and arginine and proline metabolism pathways. Predictivity for adverse outcomes in mammalian prenatal developmental toxicity studies used ToxRefDB and other sources of information, including Stemina Biomarker Discovery's predictive DevTox® model trained on 23 pharmaceutical agents of known developmental toxicity and differing potency. The model initially predicted developmental toxicity from the blinded ToxCast compounds in concordance with animal data with 73% accuracy. Retraining the model with data from the unblinded test compounds at one concentration level increased the predictive accuracy for the remaining concentrations to 83%. These preliminary results on a 11-chemical subset of the ToxCast chemical library indicate that metabolomics analysis of the hES secretome provides information valuable for predictive modeling and mechanistic understanding of mammalian developmental toxicity. -- Highlights: ► We tested 11 environmental compounds in a hESC metabolomics platform. ► Significant changes in secreted small molecule metabolites were observed. ► Perturbed mass features map to pathways critical for normal development and pregnancy. ► Arginine, proline, nicotinate, nicotinamide and glutathione pathways were affected.

Comparative analysis of pharmaceuticals versus industrial chemicals acute aquatic toxicity classification according to the United Nations classification system for chemicals. Assessment of the (Q)SAR predictability of pharmaceuticals acute aquatic toxicity and their predominant acute toxic mode-of-action

DEFF Research Database (Denmark)

Sanderson, Hans; Thomsen, Marianne

2009-01-01

data. Pharmaceuticals were found to be more frequent than industrial chemicals in GHS category III. Acute toxicity was predictable (>92%) using a generic (Q)SAR ((Quantitative) Structure Activity Relationship) suggesting a narcotic MOA. Analysis of model prediction error suggests that 68...

Analysis of accident sequences and source terms at waste treatment and storage facilities for waste generated by U.S. Department of Energy Waste Management Operations, Volume 3: Appendixes C-H

International Nuclear Information System (INIS)

Mueller, C.; Nabelssi, B.; Roglans-Ribas, J.

1995-04-01

This report contains the Appendices for the Analysis of Accident Sequences and Source Terms at Waste Treatment and Storage Facilities for Waste Generated by the U.S. Department of Energy Waste Management Operations. The main report documents the methodology, computational framework, and results of facility accident analyses performed as a part of the U.S. Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies are assessed, and the resultant radiological and chemical source terms are evaluated. A personal computer-based computational framework and database have been developed that provide these results as input to the WM PEIS for calculation of human health risk impacts. This report summarizes the accident analyses and aggregates the key results for each of the waste streams. Source terms are estimated and results are presented for each of the major DOE sites and facilities by WM PEIS alternative for each waste stream. The appendices identify the potential atmospheric release of each toxic chemical or radionuclide for each accident scenario studied. They also provide discussion of specific accident analysis data and guidance used or consulted in this report

Analysis of accident sequences and source terms at waste treatment and storage facilities for waste generated by U.S. Department of Energy Waste Management Operations, Volume 3: Appendixes C-H

Energy Technology Data Exchange (ETDEWEB)

Mueller, C.; Nabelssi, B.; Roglans-Ribas, J. [and others

1995-04-01

This report contains the Appendices for the Analysis of Accident Sequences and Source Terms at Waste Treatment and Storage Facilities for Waste Generated by the U.S. Department of Energy Waste Management Operations. The main report documents the methodology, computational framework, and results of facility accident analyses performed as a part of the U.S. Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies are assessed, and the resultant radiological and chemical source terms are evaluated. A personal computer-based computational framework and database have been developed that provide these results as input to the WM PEIS for calculation of human health risk impacts. This report summarizes the accident analyses and aggregates the key results for each of the waste streams. Source terms are estimated and results are presented for each of the major DOE sites and facilities by WM PEIS alternative for each waste stream. The appendices identify the potential atmospheric release of each toxic chemical or radionuclide for each accident scenario studied. They also provide discussion of specific accident analysis data and guidance used or consulted in this report.

1995 Toxic chemical release inventory: Emergency Planning and Community Right-to-Know Act of 1986, Section 313

International Nuclear Information System (INIS)

Mincey, S.L.

1996-08-01

Section 313 of the Emergency Planning and Community Right-To-Know Act (EPCRA) requires the annual submittal of toxic chemical release information to the U.S. Environmental Protection Agency.Executive Order 12856, 'Federal Compliance With Right-to-Know Laws and Pollution Prevention Requirements' extends the requirements of EPCRA to all Federal agencies. The following document is the August 1996 submittal of the Hanford Site Toxic Chemical Release Inventory report. Included is a Form R for ethylene glycol, the sole chemical used in excess of the established regulatory thresholds at the Hanford Site by the U.S. Department of Energy, Richland Operations Office and its contractors during Calendar Year 1995

Occupational hazards in hospitals: accidents, radiation, exposure to noxious chemicals, drug addiction and psychic problems, and assault

Energy Technology Data Exchange (ETDEWEB)

Gestal, J.J.

1987-08-01

Except for infectious diseases all the main occupational hazards affecting health workers are reviewed: accidents (explosions, fires, electrical accidents, and other sources of injury); radiation (stochastic and non-stochastic effects, protective measures, and personnel most at risk); exposure to noxious chemicals, whose effects may be either local (allergic eczema) or generalised (cancer, mutations), particular attention being paid to the hazards presented by formol, ethylene oxide, cytostatics, and anaesthetic gases; drug addiction (which is more common among health workers than the general population) and psychic problems associated with promotion, shift work, and emotional stress; and assault (various types of assault suffered by health workers, its causes, and the characterisation of the most aggressive patients).

Occupational hazards in hospitals: accidents, radiation, exposure to noxious chemicals, drug addiction and psychic problems, and assault

International Nuclear Information System (INIS)

Gestal, J.J.

1987-01-01

Except for infectious diseases all the main occupational hazards affecting health workers are reviewed: accidents (explosions, fires, electrical accidents, and other sources of injury); radiation (stochastic and non-stochastic effects, protective measures, and personnel most at risk); exposure to noxious chemicals, whose effects may be either local (allergic eczema) or generalised (cancer, mutations), particular attention being paid to the hazards presented by formol, ethylene oxide, cytostatics, and anaesthetic gases; drug addiction (which is more common among health workers than the general population) and psychic problems associated with promotion, shift work, and emotional stress; and assault (various types of assault suffered by health workers, its causes, and the characterisation of the most aggressive patients). (author)

Monitoring and trace detection of hazardous waste and toxic chemicals using resonance Raman spectroscopy

International Nuclear Information System (INIS)

Sedlacek, A.J. III; Dougherty, D.R.; Chen, C.L.

1993-01-01

Raman scattering is a coherent, inelastic, two-photon process, which shifts the frequency of an outgoing photon according to the vibrational structure of the irradiated species, thereby providing a unique fingerprint of the molecule. When involving an allowed electronic transition (resonance Raman), this scattering cross section can be enhanced by 10 4 to 10 6 and provides the basis for a viable technique that can monitor and detect trace quantities of hazardous wastes and toxic chemicals. Resonance Raman spectroscopy (RRS) possesses many of the ideal characteristics for monitoring and detecting of hazardous waste and toxic chemicals. Some of these traits are: (1) very high selectivity (chemical specific fingerprints); (2) independence from the excitation wavelength (ability to monitor in the solar blind region); (3) chemical mixture fingerprints are the sum of its individual components (no spectral cross-talk); (4) near independence of the Raman fingerprint to its physical state (very similar spectra for gas, liquid, solid and solutions -- either bulk or aerosols); and (5) insensitivity of the Raman signature to environmental conditions (no quenching). Data from a few chemicals will be presented which illustrate these features. In cases where background fluorescence accompanies the Raman signals, an effective frequency modulation technique has been developed, which can completely eliminate this interference

76 FR 38169 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

Science.gov (United States)

2011-06-29

... (7405M), Office of Pollution Prevention and Toxics, Environmental Protection Agency, 1200 Pennsylvania... gold leaf, dyeing mixtures, antifreeze mixtures, extraction of resins and waxes, preservative for...: June 21, 2011. Maria J. Doa, Director, Chemical Control Division, Office of Pollution Prevention and...

76 FR 69136 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting

Science.gov (United States)

2011-11-08

... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting AGENCY: Environmental Protection Agency (EPA). ACTION: Lifting of Administrative Stay for Hydrogen Sulfide; Correction. SUMMARY: The... Administrative Stay of the reporting requirements for hydrogen sulfide. The Office of the Federal Register...

History of EPI Suite™ and future perspectives on chemical property estimation in US Toxic Substances Control Act new chemical risk assessments.

Science.gov (United States)

Card, Marcella L; Gomez-Alvarez, Vicente; Lee, Wen-Hsiung; Lynch, David G; Orentas, Nerija S; Lee, Mari Titcombe; Wong, Edmund M; Boethling, Robert S

2017-03-22

Chemical property estimation is a key component in many industrial, academic, and regulatory activities, including in the risk assessment associated with the approximately 1000 new chemical pre-manufacture notices the United States Environmental Protection Agency (US EPA) receives annually. The US EPA evaluates fate, exposure and toxicity under the 1976 Toxic Substances Control Act (amended by the 2016 Frank R. Lautenberg Chemical Safety for the 21 st Century Act), which does not require test data with new chemical applications. Though the submission of data is not required, the US EPA has, over the past 40 years, occasionally received chemical-specific data with pre-manufacture notices. The US EPA has been actively using this and publicly available data to develop and refine predictive computerized models, most of which are housed in EPI Suite™, to estimate chemical properties used in the risk assessment of new chemicals. The US EPA develops and uses models based on (quantitative) structure-activity relationships ([Q]SARs) to estimate critical parameters. As in any evolving field, (Q)SARs have experienced successes, suffered failures, and responded to emerging trends. Correlations of a chemical structure with its properties or biological activity were first demonstrated in the late 19 th century and today have been encapsulated in a myriad of quantitative and qualitative SARs. The development and proliferation of the personal computer in the late 20 th century gave rise to a quickly increasing number of property estimation models, and continually improved computing power and connectivity among researchers via the internet are enabling the development of increasingly complex models.

Zebrafish Get Connected: Investigating Neurotransmission Targets and Alterations in Chemical Toxicity

Directory of Open Access Journals (Sweden)

Katharine A. Horzmann

2016-08-01

Full Text Available Neurotransmission is the basis of neuronal communication and is critical for normal brain development, behavior, learning, and memory. Exposure to drugs and chemicals can alter neurotransmission, often through unknown pathways and mechanisms. The zebrafish (Danio rerio model system is increasingly being used to study the brain and chemical neurotoxicity. In this review, the major neurotransmitter systems, including glutamate, GABA, dopamine, norepinephrine, serotonin, acetylcholine, histamine, and glutamate are surveyed and pathways of synthesis, transport, metabolism, and action are examined. Differences between human and zebrafish neurochemical pathways are highlighted. We also review techniques for evaluating neurological function, including the measurement of neurotransmitter levels, assessment of gene expression through transcriptomic analysis, and the recording of neurobehavior. Finally examples of chemical toxicity studies evaluating alterations in neurotransmitter systems in the zebrafish model are reviewed.

Investigations with beagles about toxicity and radioprotective effect of the chemical radioprotection substance WR 2721

International Nuclear Information System (INIS)

Wagner, M.; Sedlmeier, H.; Wustrow, T.; Messerschmidt, O.

1980-01-01

The toxicity of the chemical radioprotection substance WR 2721 (S-2-(3-aminopropylamino)ethyl-thiophosphate) was examined in 25 beagles. The study showed that the toxicity of the substance increases as the dose gets higher. Between the doses 200 and 250 mg/kg of body weight, the increase of toxicity was significantly greater than could be expected on the basis of the dose difference. Until a dose of 200 mg/kg, the authors found no side effects which would have disturbed vital functions, but higher doses led to marked symptoms of intoxication. (orig.) [de

Case study on chemical plant accidents for flow-sheet design of the HTTR-IS system

International Nuclear Information System (INIS)

Homma, Hiroyuki; Sato, Hiroyuki; Kasahara, Seiji; Hara, Teruo; Kato, Ryoma; Sakaba, Nariaki; Ohashi, Hirofumi

2007-02-01

At the present time, we are alarmed by depletion of fossil energy and adverse effect of rapid increase in fossil fuel burning on environment such as climate changes and acid rain, because our lives depend still heavily upon fossil energy. It is thus widely recognized that hydrogen is one of important future energy carriers in which it is used without emission of carbon dioxide greenhouse gas and atmospheric pollutants and that hydrogen demand will increase greatly as fuel cells are developed and applied widely in the near future. To meet massive demand of hydrogen, hydrogen production from water utilizing nuclear, especially by thermochemical water-splitting Iodine-Sulphur (IS) process utilizing heat from High-Temperature Gas-cooled Reactors (HTGRs), offers one of the most attractive zero-emission energy strategies and the only one practical on a substantial scale. However, to establish a technology based for the HTGR hydrogen production by the IS process, we should close several technology gaps through R and D with the High-Temperature Engineering Test Reactor (HTTR), which is the only Japanese HTGR built and operated at the Oarai Research and Development Centre of Japan Atomic Energy Agency (JAEA). We have launched design studies of the IS process hydrogen production system coupled with the HTTR (HTTR-IS system) to demonstrate HTGR hydrogen production. In designing the HTTR-IS system, it is necessary to consider preventive and breakdown maintenance against accidents occurred in the IS process as a chemical plant. This report describes case study on chemical plant accidents relating to the IS process plant and shows a proposal of accident protection measures based on above case study, which is necessary for flow-sheet design of the HTTR-IS system. (author)

Guidance on health effects of toxic chemicals. Safety Analysis Report Update Program

Energy Technology Data Exchange (ETDEWEB)

Foust, C.B.; Griffin, G.D.; Munro, N.B.; Socolof, M.L.

1994-02-01

Martin Marietta Energy Systems, Inc. (MMES), and Martin Marietta Utility Services, Inc. (MMUS), are engaged in phased programs to update the safety documentation for the existing US Department of Energy (DOE)-owned facilities. The safety analysis of potential toxic hazards requires a methodology for evaluating human health effects of predicted toxic exposures. This report provides a consistent set of health effects and documents toxicity estimates corresponding to these health effects for some of the more important chemicals found within MMES and MMUS. The estimates are based on published toxicity information and apply to acute exposures for an ``average`` individual. The health effects (toxicological endpoints) used in this report are (1) the detection threshold; (2) the no-observed adverse effect level; (3) the onset of irritation/reversible effects; (4) the onset of irreversible effects; and (5) a lethal exposure, defined to be the 50% lethal level. An irreversible effect is defined as a significant effect on a person`s quality of life, e.g., serious injury. Predicted consequences are evaluated on the basis of concentration and exposure time.

75 FR 19319 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting; Extension of Comment...

Science.gov (United States)

2010-04-14

... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting; Extension of Comment Period... reporting requirements for hydrogen sulfide (Chemical Abstracts Service Number (CAS No.) 7783-06-4) (75 FR... may be potentially affected by this action if you manufacture, process, or otherwise use hydrogen...

Numerical Simulations as Tool to Predict Chemical and Radiological Hazardous Diffusion in Case of Nonconventional Events

Directory of Open Access Journals (Sweden)

J.-F. Ciparisse

2016-01-01

Full Text Available CFD (Computational Fluid Dynamics simulations are widely used nowadays to predict the behaviour of fluids in pure research and in industrial applications. This approach makes it possible to get quantitatively meaningful results, often in good agreement with the experimental ones. The aim of this paper is to show how CFD calculations can help to understand the time evolution of two possible CBRNe (Chemical-Biological-Radiological-Nuclear-explosive events: (1 hazardous dust mobilization due to the interaction between a jet of air and a metallic powder in case of a LOVA (Loss Of Vacuum Accidents that is one of the possible accidents that can occur in experimental nuclear fusion plants; (2 toxic gas release in atmosphere. The scenario analysed in the paper has consequences similar to those expected in case of a release of dangerous substances (chemical or radioactive in enclosed or open environment during nonconventional events (like accidents or man-made or natural disasters.

Use of computer-assisted prediction of toxic effects of chemical substances

International Nuclear Information System (INIS)

Simon-Hettich, Brigitte; Rothfuss, Andreas; Steger-Hartmann, Thomas

2006-01-01

The current revision of the European policy for the evaluation of chemicals (REACH) has lead to a controversy with regard to the need of additional animal safety testing. To avoid increases in animal testing but also to save time and resources, alternative in silico or in vitro tests for the assessment of toxic effects of chemicals are advocated. The draft of the original document issued in 29th October 2003 by the European Commission foresees the use of alternative methods but does not give further specification on which methods should be used. Computer-assisted prediction models, so-called predictive tools, besides in vitro models, will likely play an essential role in the proposed repertoire of 'alternative methods'. The current discussion has urged the Advisory Committee of the German Toxicology Society to present its position on the use of predictive tools in toxicology. Acceptable prediction models already exist for those toxicological endpoints which are based on well-understood mechanism, such as mutagenicity and skin sensitization, whereas mechanistically more complex endpoints such as acute, chronic or organ toxicities currently cannot be satisfactorily predicted. A potential strategy to assess such complex toxicities will lie in their dissection into models for the different steps or pathways leading to the final endpoint. Integration of these models should result in a higher predictivity. Despite these limitations, computer-assisted prediction tools already today play a complementary role for the assessment of chemicals for which no data is available or for which toxicological testing is impractical due to the lack of availability of sufficient compounds for testing. Furthermore, predictive tools offer support in the screening and the subsequent prioritization of compound for further toxicological testing, as expected within the scope of the European REACH program. This program will also lead to the collection of high-quality data which will broaden the

Emergency Response System for Pollution Accidents in Chemical Industrial Parks, China

Directory of Open Access Journals (Sweden)

Weili Duan

2015-07-01

Full Text Available In addition to property damage and loss of lives, environment pollution, such as water pollution and air pollution caused by accidents in chemical industrial parks (CIPs is a significant issue in China. An emergency response system (ERS was therefore planned to properly and proactively cope with safety incidents including fire and explosions occurring in the CIPs in this study. Using a scenario analysis, the stages of emergency response were divided into three levels, after introducing the domino effect, and fundamental requirements of ERS design were confirmed. The framework of ERS was composed mainly of a monitoring system, an emergency command center, an action system, and a supporting system. On this basis, six main emergency rescue steps containing alarm receipt, emergency evaluation, launched corresponding emergency plans, emergency rescue actions, emergency recovery, and result evaluation and feedback were determined. Finally, an example from the XiaoHu Chemical Industrial Park (XHCIP was presented to check on the integrality, reliability, and maneuverability of the ERS, and the result of the first emergency drill with this ERS indicated that the developed ERS can reduce delays, improve usage efficiency of resources, and raise emergency rescue efficiency.

40 CFR 68.168 - Five-year accident history.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Five-year accident history. 68.168 Section 68.168 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.168 Five-year accident history...

Therapeutic values, chemical constituents and toxicity of Taiwanese Dysosma pleiantha--a review.

Science.gov (United States)

Karuppaiya, Palaniyandi; Tsay, Hsin Sheng

2015-07-16

Dysosma pleiantha (Hance) Woodson also called as Bajiaolian belongs to the family Berberidaceae, is widely used in Taiwan as traditional Chinese herbal medicine for more than thousands of years. It is usually recommended by various traditional Chinese medical doctors and herbal pharmacies for general remedies including postpartum recovery, treatment of weakness, neck mass, acne, hepatoma, lumbago, snakebite, tumor growth and dysmenorrhea. In the textbooks of traditional Chinese medicine, there is limited information about the toxicity of Bajiaolian. Podophyllotoxin, a lignan is the main toxic ingredient of Bajiaolian rhizome. Therefore, Bajiaolian is documented as the fifth highest cause of poisoning among the herbal medicine in Taiwan. Since the therapeutic and toxic doses are very close, Bajiaolian poisoning cases are frequently reported in Taiwan. Moreover, Dysosma poisoning cases are difficult to diagnosis because physicians are unfamiliar with this medicine's multiple clinical presentations in different stages of intoxication. Therefore, the objective of this review is to represent the collective information available in literatures regarding D. pleiantha, a cytotoxic lignan containing medicinal plant. Specifically, the literatures have been reviewed for articles pertaining to chemical constituents, properties, therapeutical benefits, toxicity, poisoning symptoms, toxic as well as therapeutic dose and medical management. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Biodegradation of toxic chemicals by Pleurotus eryngii in submerged fermentation and solid-state fermentation.

Science.gov (United States)

Chang, Bea-Ven; Chang, Yi-Ming

2016-04-01

The toxic chemicals bisphenol A (BPA), bisphenol F (BPF), nonylphenol (NP), and tetrabromobisphenol A (TBBPA) are endocrine-disrupting chemicals that have consequently drawn much concern regarding their effect on the environment. The objectives of this study were to investigate the degradation of BPA, BPF, NP, and TBBPA by enzymes from Pleurotus eryngii in submerged fermentation (SmF) and solid-state fermentation (SSF), and also to assess the removal of toxic chemicals in spent mushroom compost (SMC). BPA and BPF were analyzed by high-performance liquid chromatography; NP and TBBPA were analyzed by gas chromatography. NP degradation was enhanced by adding CuSO4 (1 mM), MnSO4 (0.5 mM), gallic acid (1 mM), tartaric acid (20 mM), citric acid (20 mM), guaiacol (1 mM), or 2,2'-azino-bis- (3-ethylbenzothiazoline-6-sulfonic acid; 1 mM), with the last yielding a higher NP degradation rate than the other additives from SmF. The optimal conditions for enzyme activity from SSF were a sawdust/wheat bran ratio of 1:4 and a moisture content of 5 mL/g. The enzyme activities were higher with sawdust/wheat bran than with sawdust/rice bran. The optimal conditions for the extraction of enzyme from SMC required using sodium acetate buffer (pH 5.0, solid/solution ratio 1:5), and extraction over 3 hours. The removal rates of toxic chemicals by P. eryngii, in descending order of magnitude, were SSF > SmF > SMC. The removal rates were BPF > BPA > NP > TBBPA. Copyright © 2014. Published by Elsevier B.V.

Chemical concentrations, exposures, health risks by census tract from National Scale Air Toxics Assessment (NATA)

Data.gov (United States)

U.S. Environmental Protection Agency — Chemical concentrations, exposures, health risks by census tract for the United States from National Scale Air Toxics Assessment (NATA). This dataset is associated...

Analysis of accident sequences and source terms at treatment and storage facilities for waste generated by US Department of Energy waste management operations

Energy Technology Data Exchange (ETDEWEB)

Mueller, C.; Nabelssi, B.; Roglans-Ribas, J.; Folga, S.; Policastro, A.; Freeman, W.; Jackson, R.; Mishima, J.; Turner, S.

1996-12-01

This report documents the methodology, computational framework, and results of facility accident analyses performed for the US Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies assessed, and the resultant radiological and chemical source terms evaluated. A personal-computer-based computational framework and database have been developed that provide these results as input to the WM PEIS for the calculation of human health risk impacts. The WM PEIS addresses management of five waste streams in the DOE complex: low-level waste (LLW), hazardous waste (HW), high-level waste (HLW), low-level mixed waste (LLMW), and transuranic waste (TRUW). Currently projected waste generation rates, storage inventories, and treatment process throughputs have been calculated for each of the waste streams. This report summarizes the accident analyses and aggregates the key results for each of the waste streams. Source terms are estimated, and results are presented for each of the major DOE sites and facilities by WM PEIS alternative for each waste stream. Key assumptions in the development of the source terms are identified. The appendices identify the potential atmospheric release of each toxic chemical or radionuclide for each accident scenario studied. They also discuss specific accident analysis data and guidance used or consulted in this report.

Insect-gene-activity detection system for chemical and biological warfare agents and toxic industrial chemicals

Science.gov (United States)

Mackie, Ryan S.; Schilling, Amanda S.; Lopez, Arturo M.; Rayms-Keller, Alfredo

2002-02-01

Detection of multiple chemical and biological weapons (CBW) agents and/or complex mixtures of toxic industrial chemicals (TIC) is imperative for both the commercial and military sectors. In a military scenario, a multi-CBW attack would create confusion, thereby delaying decontamination and therapeutic efforts. In the commercial sector, polluted sites invariably contain a mixture of TIC. Novel detection systems capable of detecting CBW and TIC are sorely needed. While it may be impossible to build a detector capable of discriminating all the possible combinations of CBW, a detection system capable of statistically predicting the most likely composition of a given mixture is within the reach of current emerging technologies. Aquatic insect-gene activity may prove to be a sensitive, discriminating, and elegant paradigm for the detection of CBW and TIC. We propose to systematically establish the expression patterns of selected protein markers in insects exposed to specific mixtures of chemical and biological warfare agents to generate a library of biosignatures of exposure. The predicting capabilities of an operational library of biosignatures of exposures will allow the detection of emerging novel or genetically engineered agents, as well as complex mixtures of chemical and biological weapons agents. CBW and TIC are discussed in the context of war, terrorism, and pollution.

Environmental toxicity of Chemical Warfare Agents (CWAs) - MicrotoxTM and Spontaneous Locomotor Changes

DEFF Research Database (Denmark)

Storgaard, Morten Swayne; Sanderson, Hans; Baatrup, Erik

After the 2nd World War the CWAs were prohibited by law and 11,000 tonnes of toxic agents were dumped in the Bornholm Basin east of Bornholm. The dumped chemical munitions have not reached attention from politicians and scientists until recently. During earlier projects, such as MERCW (2005...

Genetic and chemical modifiers of a CUG toxicity model in Drosophila.

Directory of Open Access Journals (Sweden)

Amparo Garcia-Lopez

2008-02-01

Full Text Available Non-coding CUG repeat expansions interfere with the activity of human Muscleblind-like (MBNL proteins contributing to myotonic dystrophy 1 (DM1. To understand this toxic RNA gain-of-function mechanism we developed a Drosophila model expressing 60 pure and 480 interrupted CUG repeats in the context of a non-translatable RNA. These flies reproduced aspects of the DM1 pathology, most notably nuclear accumulation of CUG transcripts, muscle degeneration, splicing misregulation, and diminished Muscleblind function in vivo. Reduced Muscleblind activity was evident from the sensitivity of CUG-induced phenotypes to a decrease in muscleblind genetic dosage and rescue by MBNL1 expression, and further supported by the co-localization of Muscleblind and CUG repeat RNA in ribonuclear foci. Targeted expression of CUG repeats to the developing eye and brain mushroom bodies was toxic leading to rough eyes and semilethality, respectively. These phenotypes were utilized to identify genetic and chemical modifiers of the CUG-induced toxicity. 15 genetic modifiers of the rough eye phenotype were isolated. These genes identify putative cellular processes unknown to be altered by CUG repeat RNA, and they include mRNA export factor Aly, apoptosis inhibitor Thread, chromatin remodelling factor Nurf-38, and extracellular matrix structural component Viking. Ten chemical compounds suppressed the semilethal phenotype. These compounds significantly improved viability of CUG expressing flies and included non-steroidal anti-inflammatory agents (ketoprofen, muscarinic, cholinergic and histamine receptor inhibitors (orphenadrine, and drugs that can affect sodium and calcium metabolism such as clenbuterol and spironolactone. These findings provide new insights into the DM1 phenotype, and suggest novel candidates for DM1 treatments.

Dependence of Nanoparticle Toxicity on Their Physical and Chemical Properties

Science.gov (United States)

Sukhanova, Alyona; Bozrova, Svetlana; Sokolov, Pavel; Berestovoy, Mikhail; Karaulov, Alexander; Nabiev, Igor

2018-02-01

Studies on the methods of nanoparticle (NP) synthesis, analysis of their characteristics, and exploration of new fields of their applications are at the forefront of modern nanotechnology. The possibility of engineering water-soluble NPs has paved the way to their use in various basic and applied biomedical researches. At present, NPs are used in diagnosis for imaging of numerous molecular markers of genetic and autoimmune diseases, malignant tumors, and many other disorders. NPs are also used for targeted delivery of drugs to tissues and organs, with controllable parameters of drug release and accumulation. In addition, there are examples of the use of NPs as active components, e.g., photosensitizers in photodynamic therapy and in hyperthermic tumor destruction through NP incorporation and heating. However, a high toxicity of NPs for living organisms is a strong limiting factor that hinders their use in vivo. Current studies on toxic effects of NPs aimed at identifying the targets and mechanisms of their harmful effects are carried out in cell culture models; studies on the patterns of NP transport, accumulation, degradation, and elimination, in animal models. This review systematizes and summarizes available data on how the mechanisms of NP toxicity for living systems are related to their physical and chemical properties.

Toxicity of fire retardant chemicals and fire suppressant foams to vertebrate and invertebrate wildlife species

Science.gov (United States)

Vyas, Nimish B.; Hill, Elwood F.

1996-01-01

Under laboratory conditions, acute single-dose oral toxicity tests (LD50) were conducted with three fire retardant chemicals (Fire-Trol GTS-R, Phos-Chek D75-F, and Fire-Trol LCG-R) and two fire suppressant foams (Silv-Ex and Phos-Chek WD-881) to determine effects on adult northern bobwhite, American kestrel, red-winged blackbird, and white-footed mouse. In addition, earthworms were exposed (LC50) for 14 days in treated soil.In general, no toxic responses were evident. For northern bobwhite, the LD50 for all five chemicals was >2000 mg a.l./kg of body mass. American kestrels regurgitated all chemicals except Silv-ex; LD50s all exceeded 2000 mg/kg. The LD50 for red-winged blackbird was also >2000 mg/kg for all chemicals except Fire-Trol GTS-R which is currently undergoing further testing. In addition, the LD50 for white-footed mouse was >2000 mg/kg for Phos-Chek D75F. The 14-day LC50 for earthworms was >1000 ppm for all chemicals. Therefore, we concluded that these retardants and foams do not pose an acute hazard to adult birds, mammals, or earthworms. However, ecological studies to evaluate the potential effects of these formulations on vertebrate behavior and population dynamics are in progress.

Exploring Chemical Routes Relevant to the Toxicity of Paracetamol and Its meta-Analogue at a Molecular Level.

Science.gov (United States)

Castañeda-Arriaga, Romina; Galano, Annia

2017-06-19

Several chemical routes related to the toxicity of paracetamol (APAP, also known as acetaminophen), its analogue N-acetyl-m-aminophenol (AMAP), and their deacetylated derivatives, were investigated using the density functional theory. It was found that AMAP is more resilient to chemical oxidation than APAP. The chemical degradation of AMAP into radical intermediates is predicted to be significant only when it is induced by strong oxidants. This might explain the apparent contradictions among experimental evidence regarding AMAP toxicity. All of the investigated species are incapable of oxidizing DNA, but they can damage lipids by H atom transfer (HAT) from the bis-allylic site, with the phenoxyl radical of AMAP being the most threatening to the lipids' chemical integrity. Regarding protein damage, Cys residues were identified as the most likely targets. The damage in this case may involve two different routes: (i) HAT from the thiol site by phenoxyl radicals and (ii) protein arylation by the quinone imine (QI) derivatives. Both are not only thermochemically viable, but also are very fast reactions. According to the mechanism identified here as the most likely one for protein arylation, a rather large concentration of QI would be necessary for this damage to be significant. This might explain why APAP is nontoxic in therapeutic doses, while overdoses can result in hepatic toxicity. In addition, the QI derived from both APAP and AMAP were found to be capable of inflicting this kind of damage. In addition, it is proposed that they might increase • OH production via the Fenton reaction, which would contribute to their toxicity.

ToxiFly: Can Fruit Flies be Used to Identify Toxicity Pathways for Airborne Chemicals?

Science.gov (United States)

Current high-throughput and alternative screening assays for chemical toxicity are unable to test volatile organic compounds (VOCs), thus limiting their scope. Further, the data generated by these assays require mechanistic information to link effects at molecular targets to adve...

Generally applicable limits on intakes of uranium based on its chemical toxicity and the radiological significance of intakes at those limits

International Nuclear Information System (INIS)

Thorne, M C; Wilson, J

2015-01-01

Uranium is chemically toxic and radioactive, and both considerations have to be taken into account when limiting intakes of the element, in the context of both occupational and public exposures. Herein, the most recent information available on the chemical toxicity and biokinetics of uranium is used to propose new standards for limiting intakes of the element. The approach adopted allows coherent standards to be set for ingestion and inhalation of different chemical forms of the element by various age groups. It also allows coherent standards to be set for occupational and public exposures (including exposures of different age groups) and for various exposure regimes (including short-term and chronic exposures). The proposed standards are more restrictive than those used previously, but are less restrictive than the Minimal Risk Levels proposed recently by the US Agency for Toxic Substances and Disease Registry. Having developed a set of proposed limits based solely on chemical toxicity considerations, the radiological implications of exposure at those proposed limits are investigated for natural, depleted and enriched uranium. (paper)

Radioactive particles revealed by electron microscopy. Chemical and physical properties of radioactive particles in aerosol samples emitted during the early stage of Fukushima Dai-ichi Nuclear Power Plant accident

International Nuclear Information System (INIS)

Adachi, Kouji

2015-01-01

Water-insoluble radioactive materials emitted during an early stage of the Fukushima Dai-ichi Nuclear Power Plant accident in 2011 were identified, and their chemical and physical properties were characterized as particulate matters. In this report, studies on radioactive particles collected from filter samples in Tsukuba on March 14–15, 2011 are summarized. Their compositions, chemical states, sizes, shapes, crystallinity, and hygroscopicity were analyzed using microscopic analyses such as electron microscopy and synchrotron with a micro-beam. The results indicate that they include Cs, Fe, and Zn as well as elements from fission products and are water insoluble, spherical-glassy particles with ca. 2 micrometer in size. Understanding of their detailed properties is significant to improve the numerical models during the accident and to understand their occurrences in soil as well as the accident itself. In addition to the water-insoluble radioactive materials, water-soluble radioactive materials, which were likely emitted in different events during the accident, should be investigated to have comprehensive understanding of the accident and its environmental effects. More samples from various environments such as soil will be needed, and more detailed chemical and physical analyses will help to understand their formation process, influences on human health, and long term decrements in ambient conditions. (author)

[Risk assessment and risk control for occupational exposure to chemical toxicants from an isophorone nitrile device].

Science.gov (United States)

Wang, Dejun; Fu, Xiaokuan; Kong, Fanling; Sui, Shaofeng; Jiang, Yuanyuan; Du, Yinglin; Zhou, Jingyang

2014-06-01

Risk assessment and risk control for occupational exposure to chemical toxicants were performed on an isophorone nitrile device with an annual production of 5,000 tons, based on improved Singaporean semi-quantitative risk assessment method, with consideration of actual situation in China and in the present project. With the use of engineering analysis and identification of occupational hazards in the improved Singaporean semi-quantitative risk assessment method, hazard rating (HR) and risk assessment were performed on chemical toxicants from an isophorone nitrile device with an annual production of 5,000 tons. The chemical toxicants in the isophorone nitrile device were mainly isophorone, hydrocyanic acid, methanol, phosphoric acid, sodium hydroxide, and sodium cyanide; the HR values were mild hazard (2), extreme hazard (5), mild hazard (2), mild hazard (2), moderate hazard (3), and extreme hazard (5), respectively, and the corresponding exposure rating (ER) values were 2.09, 2.72, 2.76, 1.68, 2.0, and 1.59, respectively. The risk of chemical toxicants in this project was assessed according to the formula Risk = [HR×ER](1/2). Hydrocyanic acid was determined as high risk, sodium hydroxide and sodium cyanide as medium risk, and isophorone, methanol, and phosphoric acid as low risk. Priority in handling of risks was determined by risk rating. The table of risk control measure was established for pre-assessment of occupational hazards. With risk assessment in this study, we concluded that the isophorone nitrile device with 5,000 ton annual production was a high-occupational hazard device. This device is a project of extreme occupational hazard. The improved Singaporean semi-quantitative risk assessment method is a scientific and applicable method, and is especially suitable for pre-evaluation of on-site project with no analogy.

2002 Toxic Chemical Release Inventory Report for the Emergency Planning and Community Right-to-Know Act of 1986, Title III, Section 313

International Nuclear Information System (INIS)

Stockton, M.

2003-01-01

For reporting year 2002, Los Alamos National Laboratory (LANL or the Laboratory) submitted Form R reports for lead compounds and mercury as required under the Emergency Planning and Community Right-to-Know Act (EPCRA), Section 313. No other EPCRA Section 313 chemicals were used in 2002 above the reportable thresholds. This document was prepared to provide a description of the evaluation of EPCRA Section 313 chemical usage and threshold determinations for LANL for calendar year 2002 as well as provide background information about the data included on the Form R reports. Section 313 of EPCRA specifically requires facilities to submit a Toxic Chemical Release Inventory report (Form R) to the U.S. Environmental Protection Agency (EPA) and state agencies if the owners and operators manufacture, process, or otherwise use any of the listed toxic chemicals above listed threshold quantities. EPA compiles this data in the Toxic Release Inventory database. Form R reports for each chemical over threshold quantities must be submitted on or before July 1 each year and must cover activities that occurred at the facility during the previous year. In 1999 EPA promulgated a final rule on Persistent Bioaccumulative Toxics (PBTs). This rule added several chemicals to the EPCRA Section 313 list of toxic chemicals and established lower reporting thresholds for these and other PBT chemicals that were already reportable under EPCRA Section 313. These lower thresholds became applicable in reporting year 2000. In 2001, EPA expanded the PBT rule to include a lower reporting threshold for lead and lead compounds. Facilities that manufacture, process, or otherwise use more than 100 lb of lead or lead compounds must submit a Form R

2006 Toxic Chemical Release Inventory Report for the Emergency Planning and Community Right-to-Know Act of 1986, Title III, Section 313

Energy Technology Data Exchange (ETDEWEB)

Ecology and Air Quality Group (ENV-EAQ)

2007-12-12

For reporting year 2006, Los Alamos National Laboratory (LANL or the Laboratory) submitted Form R reports for lead as required under the Emergency Planning and Community Right-to-Know Act (EPCRA) Section 313. No other EPCRA Section 313 chemicals were used in 2006 above the reportable thresholds. This document was prepared to provide a description of the evaluation of EPCRA Section 313 chemical use and threshold determinations for LANL for calendar year 2006, as well as to provide background information about data included on the Form R reports. Section 313 of EPCRA specifically requires facilities to submit a Toxic Chemical Release Inventory Report (Form R) to the U.S. Environmental Protection Agency (EPA) and state agencies if the owners and operators manufacture, process, or otherwise use any of the listed toxic chemicals above listed threshold quantities. EPA compiles this data in the Toxic Release Inventory database. Form R reports for each chemical over threshold quantities must be submitted on or before July 1 each year and must cover activities that occurred at the facility during the previous year. In 1999, EPA promulgated a final rule on persistent bioaccumulative toxics (PBTs). This rule added several chemicals to the EPCRA Section 313 list of toxic chemicals and established lower reporting thresholds for these and other PBT chemicals that were already reportable. These lower thresholds became applicable in reporting year 2000. In 2001, EPA expanded the PBT rule to include a lower reporting threshold for lead and lead compounds. Facilities that manufacture, process, or otherwise use more than 100 lb of lead or lead compounds must submit a Form R.

Environmental Pollution, Toxicity Profile and Treatment Approaches for Tannery Wastewater and Its Chemical Pollutants.

Science.gov (United States)

Saxena, Gaurav; Chandra, Ram; Bharagava, Ram Naresh

Leather industries are key contributors in the economy of many developing countries, but unfortunately they are facing serious challenges from the public and governments due to the associated environmental pollution. There is a public outcry against the industry due to the discharge of potentially toxic wastewater having alkaline pH, dark brown colour, unpleasant odour, high biological and chemical oxygen demand, total dissolved solids and a mixture of organic and inorganic pollutants. Various environment protection agencies have prioritized several chemicals as hazardous and restricted their use in leather processing however; many of these chemicals are used and discharged in wastewater. Therefore, it is imperative to adequately treat/detoxify the tannery wastewater for environmental safety. This paper provides a detail review on the environmental pollution and toxicity profile of tannery wastewater and chemicals. Furthermore, the status and advances in the existing treatment approaches used for the treatment and/or detoxification of tannery wastewater at both laboratory and pilot/industrial scale have been reviewed. In addition, the emerging treatment approaches alone or in combination with biological treatment approaches have also been considered. Moreover, the limitations of existing and emerging treatment approaches have been summarized and potential areas for further investigations have been discussed. In addition, the clean technologies for waste minimization, control and management are also discussed. Finally, the international legislation scenario on discharge limits for tannery wastewater and chemicals has also been discussed country wise with discharge standards for pollution prevention due to tannery wastewater.

Sacrifice zones: the front lines of toxic chemical exposure in the United States

National Research Council Canada - National Science Library

Lerner, Steve

2010-01-01

... States of America. Library of Congress Cataloging-in-Publication Data Lerner, Steve. Sacrifice zones: the front lines of toxic chemical exposure in the United States / Steve Lerner. p. cm. Includes bibliographical references and index. ISBN 978-0-262-01440-3 (hardcover : alk. paper) 1. Environmental toxicology- United States- Case studies. 2. Che...

Probing nanomechanical interaction at the interface between biological membrane and potentially toxic chemical.

Science.gov (United States)

Lim, Chanoong; Park, Sohee; Park, Jinwoo; Ko, Jina; Lee, Dong Woog; Hwang, Dong Soo

2018-04-12

Various xenobiotics interact with biological membranes, and precise evaluations of the molecular interactions between them are essential to foresee the toxicity and bioavailability of existing or newly synthesized molecules. In this study, surface forces apparatus (SFA) measurement and Langmuir trough based tensiometry are performed to reveal nanomechanical interaction mechanisms between potential toxicants and biological membranes for ex vivo toxicity evaluation. As a toxicant, polyhexamethylene guanidine (PHMG) was selected because PHMG containing humidifier disinfectant and Vodka caused lots of victims in both S. Korea and Russia, respectively, due to the lack of holistic toxicity evaluation of PHMG. Here, we measured strong attraction (Wad ∼4.2 mJ/m 2 ) between PHMG and head group of biological membranes while no detectable adhesion force between the head group and control molecules was measured. Moreover, significant changes in π-A isotherm of 1,2-Dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) monolayers were measured upon PHMG adsorption. These results indicate PHMG strongly binds to hydrophilic group of lipid membranes and alters the structural and phase behavior of them. More importantly, complementary utilization of SFA and Langmuir trough techniques are found to be useful to predict the potential toxicity of a chemical by evaluating the molecular interaction with biological membranes, the primary protective barrier for living organisms. Copyright © 2018 Elsevier B.V. All rights reserved.

Acidentes químicos ampliados: um desafio para a saúde pública The increase in chemical accidents: a challenge for public health

Directory of Open Access Journals (Sweden)

Carlos M. de Freitas

1995-12-01

Full Text Available Os acidentes envolvendo substâncias perigosas nas atividades de transporte, armazenamento e produção industrial de produtos químicos constituem um sério risco à saúde e ao meio ambiente. Objetiva-se discutir, no âmbito da saúde pública, alguns dos desafios que esses tipos de acidentes colocam, principalmente para os países de economia periférica. Através da combinação de informações quantitativas e qualitativas, foram definidos e caracterizados esses tipos de acidentes e seus diversos riscos. Esses acidentes têm se apresentado com a maior gravidade nos países de economia periférica, embora a maioria deles venha ocorrendo sem o adequado registro de informações básicas para a avaliação e vigilância, como é demonstrado no caso do Rio de Janeiro (Brasil. Além da tarefa de se avaliar as conseqüências de eventos, por vezes extremamente complexos, coloca-se também, a de formular estratégias de controle e prevenção em realidades sociais que configuram um terreno fértil para a ocorrência e agravamento dos mesmos.Chemical accidents involving explosions, large fires and leakages of hazardous substances occuring during transport, storage and industrial production of chemicals constitute a real challeng to health, environmental and industrial safety professionals. The aim of this article is to discuss the main questions that this kind of accident provokes, in terms of public helth, particularly in developing countries such as Brazil. The paper defines and characterises these accidents and the various health risk they involve excluding the leakages of hazardous substances during "normal" production in industry - through the combination of quantitative and qualitative information drawn from the international literature on the subject. From some examples of chemical accidents such as occurred in Bophal (Índia, Vila Socó (Brazil, São Paulo (México and data of the World Health Organization (WHO, the authors seek to show

Acute and chronic toxicity study of the water accommodated fraction (WAF), chemically enhanced WAF (CEWAF) of crude oil and dispersant in the rock pool copepod Tigriopus japonicus.

Science.gov (United States)

Lee, Kyun-Woo; Shim, Won Joon; Yim, Un Hyuk; Kang, Jung-Hoon

2013-08-01

We determined the toxicity of the water accommodated hydrocarbon fraction (WAF), two chemically enhanced WAFs (CEWAFs; CEWAF-C, Crude oil+Corexit 9500 and CEWAF-H, Crude oil+Hiclean) of crude oil and two dispersants (Corexit 9500 and Hiclean) to the rock pool copepod Tigriopus japonicus. In the acute toxicity test, Corexit 9500 was the most toxic of all the chemicals studied. The nauplius stage of T. japonicus was more susceptible to the toxic chemicals studied than the adult female. The toxicity data using the nauplius stage was then considered as baseline to determine the spiking concentration of chemicals for chronic toxicity tests on the copepod. As the endpoints in the chronic toxicity test, survival, sex ratio, developmental time and fecundity of the copepod were used. All chemicals used in this study resulted in increased toxicity in the F1 generation. The lowest-observed-adverse-effect (LOAE) concentrations of WAF, CEWAF-H, CEWAF-C, Hiclean and Corexit 9500 were observed to be 50%, 10%, 0.1%, 1% and 1%, respectively. The results in present study imply that copepods in marine may be negatively influenced by spilled oil and dispersant. Copyright © 2013 Elsevier Ltd. All rights reserved.

Application of the MOLE in post-nuclear accident characterization

International Nuclear Information System (INIS)

Johnson, S.J.; Alvarez, J.L.

1981-01-01

Following a nuclear accident there is a need to determine the chemical composition of materials in liquid, solid and gaseous form, the crystalline structure of solids, the size and chemical composition of particles, and the chemical characterization of contaminants on surfaces. This analytical information is required to reconstruct the accident scenario, to select decontamination methods, and to determine future safety requirements. The MOLE (Molecular Optical Laser Examiner) is a Raman microprobe system which has proven to be a valuable analytical tool in providing this type of chemical information. It can determine the chemical species of polyatomic molecules and ions having characteristic Raman spectra. As little as 1 picogram of a component or a 1 μm particle can be analyzed. The imaging system can also provide mapping of selected components on a surface. A system description, sample handling techniques, and applications are presented. Specific applications to the Three Mile Island-Unit 2 accident are also addressed

Stable Chemical Dosimeters for Partial Reconstruction of Nuclear Accident Conditions

Energy Technology Data Exchange (ETDEWEB)

Dvornik, I.; Zec, U.; Baric, M.; Razem, D. [Ruder Boskovic Nuclear Institute, Zagreb, Yugoslavia (Croatia)

1969-10-15

The application of chemical dosimeters, tissue equivalent with respect to gamma rays and neutrons, is proposed for dosimetric topography of the space around nuclear devices in case of accidents. The dosimeters in the form of sealed glass ampoules have sufficient sensitivity and long-term stability and are evaluated or checked directly by conventional spectrophotometry. The sensitivity, expressed as yield per rad, is approximately equal for gamma rays and neutrons. The resolution in both cases is about one rad, and the range is up to several thousand rads. The precision of dosimetry is {+-} 1 rad or {+-} 2%, whichever is higher. In free space and unshielded the dosimeter measures the total rad-absorbed dose delivered by gamma rays and neutrons, i.e. the first collision gamma plus neutron dose. If used on- or in-phantom, especially if several dosimeters are disposed within and around the same phantom, it can give important data about the amount of the neutron component of the dose and about the effective mean energy of incident neutrons. The neutron component of the dose can be directly measured if the gamma dosimeter is used together with the chemical dosimeter. The experiments giving the change of optical density per rad and the radiation chemical yield with respect to the absorbed dose delivered by 14-MeV neutrons are described in detail. The possibility is also mentioned of applying the dosimeter as a very sensitive monitor for thermal neutrons, which is due to the chlorine content of 4.73% and activation to {sup 38}Cl. The opinion is expressed that this dosimeter deserves some attention as a part of future planning and development work on area and personnel accidental dosimetry systems. (author)

Comparative analysis of pharmaceuticals versus industrial chemicals acute aquatic toxicity classification according to the United Nations classification system for chemicals. Assessment of the (Q)SAR predictability of pharmaceuticals acute aquatic toxicity and their predominant acute toxic mode-of-action

DEFF Research Database (Denmark)

Sanderson, Hans; Thomsen, Marianne

2009-01-01

data. Pharmaceuticals were found to be more frequent than industrial chemicals in GHS category III. Acute toxicity was predictable (>92%) using a generic (Q)SAR ((Quantitative) Structure Activity Relationship) suggesting a narcotic MOA. Analysis of model prediction error suggests that 68...... a comprehensive database based on OECD's standardized measured ecotoxicological data and to evaluate if there is generally cause of greater concern with regards to pharmaceutical aquatic toxicological profiles relative to industrial chemicals. Comparisons were based upon aquatic ecotoxicity classification under...... the United Nations Global Harmonized System for classification and labeling of chemicals (GHS). Moreover, we statistically explored whether the predominant mode-of-action (MOA) for pharmaceuticals is narcosis. We found 275 pharmaceuticals with 569 acute aquatic effect data; 23 pharmaceuticals had chronic...

Evaluation of an adherent mouse embryonic stem cell in vitro assay to predict developmental toxicity of ToxCast chemicals.

Science.gov (United States)

The potential for most environmental chemicals to produce developmental toxicity is unknown. Mouse embryonic stem cell (mESC) assays are an alternative in vitro model to assess chemicals. The chemical space evaluated using mESC and compared to in vivo is limited. We used an adher...

Assessing joint toxicity of chemicals in Enchytraeus albidus (Enchytraeidae) and Porcellionides pruinosus (Isopoda) using avoidance behaviour as an endpoint

International Nuclear Information System (INIS)

Loureiro, Susana; Amorim, Monica J.B.; Campos, Bruno; Rodrigues, Sandra M.G.; Soares, Amadeu M.V.M.

2009-01-01

Contamination problems are often characterized by complex mixtures of chemicals. There are two conceptual models usually used to evaluate patterns of mixture toxicity: Concentration Addition (CA) and Independent Action (IA). Deviations from these models as synergism, antagonism and dose dependency also occur. In the present study, single and mixture toxicity of atrazine, dimethoate, lindane, zinc and cadmium were tested in Porcellionides pruinosus and Enchytraeus albidus, using avoidance as test parameter. For both species patterns of antagonism were found when exposed to dimethoate and atrazine, synergism for lindane and dimethoate exposures (with the exception of lower doses in the isopod case study) and concentration addition for cadmium and zinc occurred, while the exposure to cadmium and dimethoate showed dissimilar patterns. This study highlights the importance of dose dependencies when testing chemical mixtures and that avoidance tests can also be used to asses the effects of mixture toxicity. - Avoidance behaviour to binary mixtures of chemicals in two edaphic species

Passive dosing of pyrethroid insecticides to Daphnia magna: Expressing excess toxicity by chemical activity

DEFF Research Database (Denmark)

Nørgaard Schmidt, Stine; Gan, Jay; Kretschmann, A. C.

2015-01-01

) Effective chemical activities resulting in 50% immobilisation (Ea50) will be estimated from pyrethroid EC50 values via the correlation of sub-cooled liquid solubility (S L, [mmol/L], representing a=1) and octanol to water partitioning ratios (Kow), (3) The excess toxicity observed for pyrethroids...

The role of chemistry in nuclear accidents

International Nuclear Information System (INIS)

Johnson, C.E.; Johnson, I.

1986-01-01

An accurate description of the chemical state of fission products is required for quick response in assessing the impact of nuclide release during a nuclear accident. The chemical state of the fission products is certain to change in response to their local environment. More specifically, fission products released from fuel will change their composition on contact with high-temperature steam, and these changes will determine their behavior with regard to either transport, deposition, aerosol formation, or reaction with structural components. The local oxygen potential is a key parameter in establishing the chemical state of the fission products and their release and transport mechanisms. Knowledge of the relationship of this parameter and thermal hydraulics is needed for prediction of fission product behavior in degraded core accidents. The behavior of key fission products in various stages of an accident, based on experimental results and appropriate calculations founded on fundamental thermodynamic information, will be discussed

Toxic chemical considerations for tank farm releases. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Van Keuren, J.C.

1995-11-01

This document provides a method of determining the toxicological consequences of accidental releases from Hanford Tank Farms. A determination was made of the most restrictive toxic chemicals that are expected to be present in the tanks. Concentrations were estimated based on the maximum sample data for each analyte in all the tanks in the composite. Composite evaluated were liquids and solids from single shell tanks, double shell tanks, flammable gas watch list tanks, as well as all solids, all liquids, head space gases, and 241-C-106 solids. A sum of fractions of the health effects was computed for each composite for unit releases based emergency response planning guidelines (ERPGs). Where ERPGs were not available for chemical compounds of interest, surrogate guidelines were established. The calculation method in this report can be applied to actual release scenarios by multiplying the sum of fractions by the release rate for continuous releases, or the release amount for puff releases. Risk guidelines are met if the product is less than for equal to one.

Toxic chemical considerations for tank farm releases. Revision 1

International Nuclear Information System (INIS)

Van Keuren, J.C.

1995-11-01

This document provides a method of determining the toxicological consequences of accidental releases from Hanford Tank Farms. A determination was made of the most restrictive toxic chemicals that are expected to be present in the tanks. Concentrations were estimated based on the maximum sample data for each analyte in all the tanks in the composite. Composite evaluated were liquids and solids from single shell tanks, double shell tanks, flammable gas watch list tanks, as well as all solids, all liquids, head space gases, and 241-C-106 solids. A sum of fractions of the health effects was computed for each composite for unit releases based emergency response planning guidelines (ERPGs). Where ERPGs were not available for chemical compounds of interest, surrogate guidelines were established. The calculation method in this report can be applied to actual release scenarios by multiplying the sum of fractions by the release rate for continuous releases, or the release amount for puff releases. Risk guidelines are met if the product is less than for equal to one

Classification of baseline toxicants for QSAR predictions to replace fish acute toxicity studies.

Science.gov (United States)

Nendza, Monika; Müller, Martin; Wenzel, Andrea

2017-03-22

Fish acute toxicity studies are required for environmental hazard and risk assessment of chemicals by national and international legislations such as REACH, the regulations of plant protection products and biocidal products, or the GHS (globally harmonised system) for classification and labelling of chemicals. Alternative methods like QSARs (quantitative structure-activity relationships) can replace many ecotoxicity tests. However, complete substitution of in vivo animal tests by in silico methods may not be realistic. For the so-called baseline toxicants, it is possible to predict the fish acute toxicity with sufficient accuracy from log K ow and, hence, valid QSARs can replace in vivo testing. In contrast, excess toxicants and chemicals not reliably classified as baseline toxicants require further in silico, in vitro or in vivo assessments. Thus, the critical task is to discriminate between baseline and excess toxicants. For fish acute toxicity, we derived a scheme based on structural alerts and physicochemical property thresholds to classify chemicals as either baseline toxicants (=predictable by QSARs) or as potential excess toxicants (=not predictable by baseline QSARs). The step-wise approach identifies baseline toxicants (true negatives) in a precautionary way to avoid false negative predictions. Therefore, a certain fraction of false positives can be tolerated, i.e. baseline toxicants without specific effects that may be tested instead of predicted. Application of the classification scheme to a new heterogeneous dataset for diverse fish species results in 40% baseline toxicants, 24% excess toxicants and 36% compounds not classified. Thus, we can conclude that replacing about half of the fish acute toxicity tests by QSAR predictions is realistic to be achieved in the short-term. The long-term goals are classification criteria also for further groups of toxicants and to replace as many in vivo fish acute toxicity tests as possible with valid QSAR

An assessment of the long-term impact of chemically toxic contaminants from the disposal of nuclear fuel waste

International Nuclear Information System (INIS)

Goodwin, B.W.; Garisto, N.C.; Barnard, J.W.

1987-01-01

This paper presents a study on the potential for impact on man of chemically toxic contaminants associated with the Canadian concept for the disposal of nuclear fuel waste. The elements of concern are determined through a series of screening criteria such as elemental abundances and solubilities. A systems variability analysis approach is then used to predict the possible concentrations of these elements that may arise in the biosphere. These concentrations are compared with environmental guidelines such as permissible levels in drinking water. Conclusions are made regarding the potential for the chemically toxic contaminants to have an impact on man. 54 refs

Physical and toxic properties of hazardous chemicals regularly stored and transported in the vicinity of nuclear installations

International Nuclear Information System (INIS)

1976-03-01

This report gives a compilation of data based on information assembled by the US Nuclear Regulatory Commission and completed by the Safety and Reliability Directorate of the UK AEA, the Dutch Reactor Safety Commission, the French Atomic Energy Commission, and the CSNI Secretariat. Data sheets for a large number of hazardous chemicals are presented (from acetaldehyde to xylene), giving details of their physical and toxic properties such as: molecular weight, boiling point, vapor density, heat of vaporization, toxic concentration in air, flammability limits, toxic effects, vapor pressure data, etc.

Survey of awareness about hazardous chemicals of residents living near chemical plants in South Korea.

Science.gov (United States)

Han, Don-Hee; Park, Min Soo

2018-02-10

With economic growth, the use of chemicals has continually increased, resulting in an increase of chemical accidents. Chemical accidents pose a life threat and can lead to many health problems among the residents living in close proximity to chemical plants. This study aimed to investigate the awareness of the residents living near chemical plants about hazardous chemicals, as well as to survey the awareness of workers who do not directly handle chemicals at chemical plants (WNHCs). To this end, a questionnaire survey was conducted among a total of 600 residents and 160 WNHCs. The questionnaire was composed of three items: awareness of chemical risk, awareness of countermeasures in chemical accidents, and imperious necessity of PPE (personal protective equipment). Statistical analysis of the data was performed with the Statistical Package for Social Sciences (SPSS) version 18.0. The results show that the government needs to complement the notification system of chemical risk for residents who live close to chemical plants. The highest priority of PPE which residents want to prepare for chemical accidents was respiratory protective equipment (RPE). They responded that, if necessary to purchase PPE, they could bear a portion of the expenses (up to US $30). This study provides basic data for the development of programs and policies on chemical safety relevant for the residents living in close proximity to chemical plants in South Korea.

QSAR modeling of toxicity of diverse organic chemicals to Daphnia magna using 2D and 3D descriptors

International Nuclear Information System (INIS)

Kar, Supratik; Roy, Kunal

2010-01-01

One of the major economic alternatives to experimental toxicity testing is the use of quantitative structure-activity relationships (QSARs) which are used in formulating regulatory decisions of environmental protection agencies. In this background, we have modeled a large diverse group of 297 chemicals for their toxicity to Daphnia magna using mechanistically interpretable descriptors. Three-dimensional (3D) (electronic and spatial) and two-dimensional (2D) (topological and information content indices) descriptors along with physicochemical parameter log K o/w (n-octanol/water partition coefficient) and structural descriptors were used as predictor variables. The QSAR models were developed by stepwise multiple linear regression (MLR), partial least squares (PLS), genetic function approximation (GFA), and genetic PLS (G/PLS). All the models were validated internally and externally. Among several models developed using different chemometric tools, the best model based on both internal and external validation characteristics was a PLS equation with 7 descriptors and three latent variables explaining 67.8% leave-one-out predicted variance and 74.1% external predicted variance. The PLS model suggests that higher lipophilicity and electrophilicity, less negative charge surface area and presence of ether linkage, hydrogen bond donor groups and acetylenic carbons are responsible for greater toxicity of chemicals. The developed model may be used for prediction of toxicity, safety and risk assessment of chemicals to achieve better ecotoxicological management and prevent adverse health consequences.

QSAR modeling of toxicity of diverse organic chemicals to Daphnia magna using 2D and 3D descriptors

Energy Technology Data Exchange (ETDEWEB)

Kar, Supratik [Drug Theoretics and Cheminformatics Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Raja S C Mullick Road, Kolkata 700032 (India); Roy, Kunal, E-mail: kunalroy_in@yahoo.com [Drug Theoretics and Cheminformatics Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Raja S C Mullick Road, Kolkata 700032 (India)

2010-05-15

One of the major economic alternatives to experimental toxicity testing is the use of quantitative structure-activity relationships (QSARs) which are used in formulating regulatory decisions of environmental protection agencies. In this background, we have modeled a large diverse group of 297 chemicals for their toxicity to Daphnia magna using mechanistically interpretable descriptors. Three-dimensional (3D) (electronic and spatial) and two-dimensional (2D) (topological and information content indices) descriptors along with physicochemical parameter log K{sub o/w} (n-octanol/water partition coefficient) and structural descriptors were used as predictor variables. The QSAR models were developed by stepwise multiple linear regression (MLR), partial least squares (PLS), genetic function approximation (GFA), and genetic PLS (G/PLS). All the models were validated internally and externally. Among several models developed using different chemometric tools, the best model based on both internal and external validation characteristics was a PLS equation with 7 descriptors and three latent variables explaining 67.8% leave-one-out predicted variance and 74.1% external predicted variance. The PLS model suggests that higher lipophilicity and electrophilicity, less negative charge surface area and presence of ether linkage, hydrogen bond donor groups and acetylenic carbons are responsible for greater toxicity of chemicals. The developed model may be used for prediction of toxicity, safety and risk assessment of chemicals to achieve better ecotoxicological management and prevent adverse health consequences.

Chronic uranium exposure and growth toxicity for phytoplankton. Dose-effect relationship: first comparison of chemical and radiological toxicity

International Nuclear Information System (INIS)

Gilbin, R.; Pradines, C.; Garnier-Laplace, J.

2004-01-01

The bioavailability of uranium for freshwater organisms, as for other dissolved metals, is closely linked to chemical speciation in solution (U aqueous speciation undergoes tremendous changes in the presence of ligands commonly found in natural waters e.g. carbonate, phosphate, hydroxide and natural organic matter). For the studied chemical domain, short-term uranium uptake experiments have already shown that the free uranyl ion concentration [UO 2 2+ ] is a good predictor of uranium uptake by the green algae Chlamydomonas reinhardtii, as predicted by the Free Ion Activity Model. In agreement with these results, acidic pH and low ligands concentrations in water enhance uranium bioavailability and consequently its potential chronic effects on phytoplankton. Moreover, uranium is known to be both radio-toxic and chemo-toxic. The use of different isotopes of uranium allows to expose organisms to different radiological doses for the same molar concentration: e.g. for a given element concentration (chemical dose), replacing depleted U by U-233 obviously leads to an enhanced radiological delivered dose to organisms (x10 4 ). In this work we established relationships between uranium doses (depleted uranium and 233-U ) and effect on the growth rate of the green algae Chlamydomonas reinhardtii. Uranium bioaccumulation was also monitored. Growth rate was measured both in classical batch (0-72 hrs) and continuous (turbidostat) cultures, the latter protocol allowing medium renewal to diminish exudates accumulation and speciation changes in the medium. The differences in effects will be, if possible, related to the development of defence mechanisms against the formation of reactive oxygen species (forms of glutathione) and the production of phyto-chelatins (small peptides rich in cystein that play an important role in the homeostasis and the detoxication of metals in cells). (author)

CHEMICAL STORAGE: MYTHS VERSUS REALITY

International Nuclear Information System (INIS)

Simmons, F.

2007-01-01

A large number of resources explaining proper chemical storage are available. These resources include books, databases/tables, and articles that explain various aspects of chemical storage including compatible chemical storage, signage, and regulatory requirements. Another source is the chemical manufacturer or distributor who provides storage information in the form of icons or color coding schemes on container labels. Despite the availability of these resources, chemical accidents stemming from improper storage, according to recent reports (1) (2), make up almost 25% of all chemical accidents. This relatively high percentage of chemical storage accidents suggests that these publications and color coding schemes although helpful, still provide incomplete information that may not completely mitigate storage risks. This manuscript will explore some ways published storage information may be incomplete, examine the associated risks, and suggest methods to help further eliminate chemical storage risks

Nuclear and Chemical Weapons and Materiel: Chemical Surety

National Research Council Canada - National Science Library

2001-01-01

.... It has been revised to update responsibilities, Personnel Reliability Program (PRP) procedures, transportation policies, chemical event notification, chemical accident or incident response and assistance (CAIRA...

Nature and prevalence of non-additive toxic effects in industrially relevant mixtures of organic chemicals.

Science.gov (United States)

Parvez, Shahid; Venkataraman, Chandra; Mukherji, Suparna

2009-06-01

The concentration addition (CA) and the independent action (IA) models are widely used for predicting mixture toxicity based on its composition and individual component dose-response profiles. However, the prediction based on these models may be inaccurate due to interaction among mixture components. In this work, the nature and prevalence of non-additive effects were explored for binary, ternary and quaternary mixtures composed of hydrophobic organic compounds (HOCs). The toxicity of each individual component and mixture was determined using the Vibrio fischeri bioluminescence inhibition assay. For each combination of chemicals specified by the 2(n) factorial design, the percent deviation of the predicted toxic effect from the measured value was used to characterize mixtures as synergistic (positive deviation) and antagonistic (negative deviation). An arbitrary classification scheme was proposed based on the magnitude of deviation (d) as: additive (50%, class-IV) antagonistic/synergistic. Naphthalene, n-butanol, o-xylene, catechol and p-cresol led to synergism in mixtures while 1, 2, 4-trimethylbenzene and 1, 3-dimethylnaphthalene contributed to antagonism. Most of the mixtures depicted additive or antagonistic effect. Synergism was prominent in some of the mixtures, such as, pulp and paper, textile dyes, and a mixture composed of polynuclear aromatic hydrocarbons. The organic chemical industry mixture depicted the highest abundance of antagonism and least synergism. Mixture toxicity was found to depend on partition coefficient, molecular connectivity index and relative concentration of the components.

Household Chemical Emergencies

Science.gov (United States)

... Content Home Be Informed Household Chemical Emergencies Household Chemical Emergencies Although the risk of a chemical accident ... reduce the risk of injury. Before a Household Chemical Emergency It is critical to store household chemicals ...

Regulatory impact of nuclear reactor accident source term assumptions. Technical report

International Nuclear Information System (INIS)

Pasedag, W.F.; Blond, R.M.; Jankowski, M.W.

1981-06-01

This report addresses the reactor accident source term implications on accident evaluations, regulations and regulatory requirements, engineered safety features, emergency planning, probabilistic risk assessment, and licensing practice. Assessment of the impact of source term modifications and evaluation of the effects in Design Basis Accident analyses, assuming a change of the chemical form of iodine from elemental to cesium iodide, has been provided. Engineered safety features used in current LWR designs are found to be effective for all postulated combinations of iodine source terms under DBA conditions. In terms of potential accident consequences, it is not expected that the difference in chemical form between elemental iodine and cesium iodide would be significant. In order to account for the current information on source terms, a spectrum of accident scenerios is discussed to realistically estimate the source terms resulting from a range of potential accident conditions

Safety in the Chemical Laboratory. Epidemiology of Accidents in Academic Chemistry Laboratories, Part 2. Accident Intervention Study, Legal Aspects, and Observations.

Science.gov (United States)

Hellmann, Margaret A.; And Others

1986-01-01

Reports on a chemistry laboratory accident intervention study conducted throughout the state of Colorado. Addresses the results of an initial survey of institutions of higher learning. Discusses some legal aspects concerning academic chemistry accidents. Provides some observations about academic chemistry laboratory accidents on the whole. (TW)

Natural and active chemical remediation of toxic metals and radionuclides in the aquatic environment

International Nuclear Information System (INIS)

McPherson, G.; Pintauro, P.; O'Connor, S.; Zhang, J.; Gonzales, R.; Flowers, G.

1993-01-01

The focus of this research is the non-biological, chemical remediation of toxic heavy metals and radionuclides in aquatic environments. This Tulane/Xavier group includes researchers from Chemistry, Chemical Engineering, and Geology. Active methods using novel zeolites and ion exchange membranes are currently being evaluated for use in removing heavy metals from natural waters. In addition, field and laboratory studies of metal ion exchange reactions and competitive, heavy metal adsorption on clay substrates are underway to determine sediment metal sequestering capacity. A summary of progress to date and future work is presented

NODC Standard Format Marine Toxic Substances and Pollutants (F144) chemical identification codes (NODC Accession 9200273)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This archival information package contains a listing of codes and chemical names that were used in NODC Standard Format Marine Toxic Substances and Pollutants (F144)...

Colorimetric sensor array for determination and identification of toxic industrial chemicals.

Science.gov (United States)

Feng, Liang; Musto, Christopher J; Kemling, Jonathan W; Lim, Sung H; Zhong, Wenxuan; Suslick, Kenneth S

2010-11-15

A low-cost yet highly sensitive colorimetric sensor array for the detection and identification of toxic industrial chemicals (TICs) has been developed. The sensor consists of a disposable array of cross-responsive nanoporous pigments whose colors are changed by diverse chemical interactions with analytes. Clear differentiation among 20 different TICs has been easily achieved at both their IDLH (immediately dangerous to life or health) concentration within 2 min of exposure and PEL (permissible exposure limit) concentration within 5 min of exposure with no errors or misclassifications. Detection limits are generally well below the PEL (in most cases below 5% of PEL) and are typically in the low ppb range. The colorimetric sensor array is not responsive to changes in humidity or temperature over a substantial range. The printed arrays show excellent batch to batch reproducibility and long shelf life (greater than 3 months).

Analysis of accident sequences and source terms at treatment and storage facilities for waste generated by US Department of Energy waste management operations. Volume 1: Sections 1-9

International Nuclear Information System (INIS)

Mueller, C.; Nabelssi, B.; Roglans-Ribas, J.; Folga, S.; Policastro, A.; Freeman, W.; Jackson, R.; Mishima, J.; Turner, S.

1996-12-01

This report documents the methodology, computational framework, and results of facility accident analyses performed for the US Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies assessed, and the resultant radiological and chemical source terms evaluated. A personal-computer-based computational framework and database have been developed that provide these results as input to the WM PEIS for the calculation of human health risk impacts. The WM PEIS addresses management of five waste streams in the DOE complex: low-level waste (LLW), hazardous waste (HW), high-level waste (HLW), low-level mixed waste (LLMW), and transuranic waste (TRUW). Currently projected waste generation rates, storage inventories, and treatment process throughputs have been calculated for each of the waste streams. This report summarizes the accident analyses and aggregates the key results for each of the waste streams. Source terms are estimated, and results are presented for each of the major DOE sites and facilities by WM PEIS alternative for each waste stream. Key assumptions in the development of the source terms are identified. The appendices identify the potential atmospheric release of each toxic chemical or radionuclide for each accident scenario studied. They also discuss specific accident analysis data and guidance used or consulted in this report

2004 Toxic Chemical Release Inventory Report for the Emergency Planning and Community Right-to-Know Act of 1986, Title III, Section 313

Energy Technology Data Exchange (ETDEWEB)

M. Stockton

2006-01-15

Section 313 of Emergency Planning and Community Right-to-Know Act (EPCRA) specifically requires facilities to submit a Toxic Chemical Release Inventory Report (Form R) to the U.S. Environmental Protection Agency (EPA) and state agencies if the owners and operators manufacture, process, or otherwise use any of the listed toxic chemicals above listed threshold quantities. EPA compiles this data in the Toxic Release Inventory database. Form R reports for each chemical over threshold quantities must be submitted on or before July 1 each year and must cover activities that occurred at the facility during the previous year. For reporting year 2004, Los Alamos National Laboratory (LANL or the Laboratory) submitted Form R reports for lead compounds, nitric acid, and nitrate compounds as required under the EPCRA Section 313. No other EPCRA Section 313 chemicals were used in 2004 above the reportable thresholds. This document provides a description of the evaluation of EPCRA Section 313 chemical use and threshold determinations for LANL for calendar year 2004, as well as background information about data included on the Form R reports.

Chemical warfare agent and biological toxin-induced pulmonary toxicity: could stem cells provide potential therapies?

Science.gov (United States)

Angelini, Daniel J; Dorsey, Russell M; Willis, Kristen L; Hong, Charles; Moyer, Robert A; Oyler, Jonathan; Jensen, Neil S; Salem, Harry

2013-01-01

Chemical warfare agents (CWAs) as well as biological toxins present a significant inhalation injury risk to both deployed warfighters and civilian targets of terrorist attacks. Inhalation of many CWAs and biological toxins can induce severe pulmonary toxicity leading to the development of acute lung injury (ALI) as well as acute respiratory distress syndrome (ARDS). The therapeutic options currently used to treat these conditions are very limited and mortality rates remain high. Recent evidence suggests that human stem cells may provide significant therapeutic options for ALI and ARDS in the near future. The threat posed by CWAs and biological toxins for both civilian populations and military personnel is growing, thus understanding the mechanisms of toxicity and potential therapies is critical. This review will outline the pulmonary toxic effects of some of the most common CWAs and biological toxins as well as the potential role of stem cells in treating these types of toxic lung injuries.

Prediction of Chemical Carcinogenicity in Rodents from in vitro Genetic Toxicity Assays

Science.gov (United States)

Tennant, Raymond W.; Margolin, Barry H.; Shelby, Michael D.; Zeiger, Errol; Haseman, Joseph K.; Spalding, Judson; Caspary, William; Resnick, Michael; Stasiewicz, Stanley; Anderson, Beth; Minor, Robert

1987-05-01

Four widely used in vitro assays for genetic toxicity were evaluated for their ability to predict the carcinogenicity of selected chemicals in rodents. These assays were mutagenesis in Salmonella and mouse lymphoma cells and chromosome aberrations and sister chromatid exchanges in Chinese hamster ovary cells. Seventy-three chemicals recently tested in 2-year carcinogenicity studies conducted by the National Cancer Institute and the National Toxicology Program were used in this evaluation. Test results from the four in vitro assays did not show significant differences in individual concordance with the rodent carcinogenicity results; the concordance of each assay was approximately 60 percent. Within the limits of this study there was no evidence of complementarity among the four assays, and no battery of tests constructed from these assays improved substantially on the overall performance of the Salmonella assay. The in vitro assays which represented a range of three cell types and four end points did show substantial agreement among themselves, indicating that chemicals positive in one in vitro assay tended to be positive in the other in vitro assays. To help put this project into its proper context, we emphasize certain features of the study: 1) Standard protocols were used to mimic the major use of STTs worldwide--screening for mutagens and carcinogens; no attempt was made to optimize protocols for specific chemicals. 2) The 73 NTP chemicals and their 60% incidence of carcinogenicity are probably not representative of the universe of chemicals but rather reflect the recent chemical selection process for the NTP carcinogenicity assay. 3) The small, diverse group of chemicals precludes a meaningful evaluation of the predictive utility of chemical structure information. 4) The NTP is currently testing these same 73 chemicals in two in vivo STTs for chromosomal effects. 5) Complete data for an additional group of 30 to 40 NTP chemicals will be gathered on

Probing the ToxCastTM Chemical Library for Predictive Signatures of Developmental Toxicity - Poster at Teratology Society Annual Meeting

Science.gov (United States)

EPA’s ToxCast™ project is profiling the in vitro bioactivity of chemical compounds to assess pathway-level and cell-based signatures that correlate with observed in vivo toxicity. We hypothesize that cell signaling pathways are primary targets for diverse environmental chemicals ...

Neurodevelopmental toxicity risks due to occupational exposure to industrial chemicals during pregnancy

DEFF Research Database (Denmark)

Julvez, Jordi; Grandjean, Philippe

2009-01-01

Exposure to neurotoxic chemicals is of particular concern when it occurs during early development. The immature brain is highly vulnerable prenatally and is therefore at risk due to occupational exposures incurred by pregnant women. A systematic search of the literature has been performed...... by occupational health researchers and practitioners from the need to protect pregnant workers. Due to the vulnerability of the brain during early development, a precautionary approach to neurodevelopmental toxicity needs to be applied in occupational health....

Toxicity identification evaluation methods for identification of toxicants in refinery effluents

International Nuclear Information System (INIS)

Barten, K.A.; Mount, D.R.; Hackett, J.R.

1993-01-01

During the last five years, the authors have used Toxicity Identification Evaluation (TIE) methods to characterize and identify the source(s) of toxicity in effluents from dozens of municipal and industrial facilities. In most cases, specific chemicals responsible for toxicity have been identified. Although generally successful, the initial experience was that for several refinery effluents, they were able only to qualitatively characterize the presence of organic toxicants; standard toxicant identification procedures were not able to isolate specific organic chemicals. They believe that organic toxicity in these refinery effluents is caused by multiple organic compounds rather than by just a few; evidence for this includes an inability to isolate toxicity in a small number of fractions using liquid chromatography and the presence of very large numbers of compounds in isolated fractions. There is also evidence that the toxicant(s) may be ionic, in that the toxicity of whole effluent and isolated fractions often show increasing toxicity with decreasing pH. Finally, positive-pressure filtration has also reduced toxicity in some samples. In this presentation the authors summarize their experiences with refinery effluents, focusing on typical patterns they have observed and alternative procedures they have used to better understand the nature of these toxicants

Accidents - Chernobyl accident; Accidents - accident de Tchernobyl

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

The aquatic toxicity and chemical forms of coke plant effluent cyanide -- Implications for discharge limits

International Nuclear Information System (INIS)

Garibay, R.; Rupnow, M.; Godwin-Saad, E.; Hall, S.

1995-01-01

Cyanide is present in treated cokemaking process waters at concentrations as high as 8.0 mg/L. In assessing options for managing the discharge of a treated effluent, the development and implementation of discharge limits for cyanide became a critical issue. A study was initiated to evaluate possible alternatives to cyanide permit limits at the US Steel Gary Works Facility. The objectives of the study were to: (1) evaluation the forms of cyanide present in coke plant effluent; (2) determine whether these forms of cyanide are toxic to selected aquatic organisms; (3) compare the aquatic toxicity of various chemical forms of cyanide; (4) identify if the receiving water modifies cyanide bioavailability; and (5) confirm, with respect to water quality-based effluent limits, an appropriate analytical method for monitoring cyanide in a coke plant effluent. The results of aquatic toxicity tests and corresponding analytical data are presented. Toxicity tests were conducted with various pure chemical forms of cyanide as well as whole coke plant effluent (generated from a pilot-scale treatment system). Test species included the fathead minnow (Pimephales promelas), rainbow trout (Oncorhynchus mykiss), Ceriodaphnia dubia (C. dubia) and Daphnia magna (D. magna). Analytical measurements for cyanide included total, weak acid dissociable, diffusible cyanide and selected metal species of cyanide. The findings presented by the paper are relevant with respect to the application of cyanide water quality criteria for a coke plant effluent discharge, the translation of these water quality-based effluent limits to permit limits, and methods for compliance monitoring for cyanide

In Vitro Rat Hepatocyte Toxicity and Bacteria Genotoxicity Evaluation of High Energy Chemicals for Replacement of Hydrazine

National Research Council Canada - National Science Library

Husain, S

2002-01-01

In an effort to develop methods to predict the toxicological response of newly synthesized chemicals that are of interest to the US Air Force, in vitro rat hepatocyte toxicity and bacteria (Salmonella...

Introducing Toxics

OpenAIRE

David C. Bellinger

2013-01-01

With this inaugural issue, Toxics begins its life as a peer-reviewed, open access journal focusing on all aspects of toxic chemicals. We are interested in publishing papers that present a wide range of perspectives on toxicants and naturally occurring toxins, including exposure, biomarkers, kinetics, biological effects, fate and transport, treatment, and remediation. Toxics differs from many other journals in the absence of a page or word limit on contributions, permitting authors to present ...

Effect of alternative aging and accident simulations on polymer properties

International Nuclear Information System (INIS)

Bustard, L.D.; Chenion, J.; Carlin, F.; Alba, C.; Gaussens, G.; LeMeur, M.

1985-05-01

The influence of accident irradiation, steam, and chemical spray exposures on the behavior of twenty-three age-preconditioned polymer sample sets (twenty-one different materials) has been investigated. The test program varied the following conditions: (1) Accident simulations of irradiation and thermodynamic (steam and chemical spray) conditions were performed both sequentially and simultaneously. (2) Accident thermodynamic (steam and chemical spray) exposures were performed both with and without air present during the exposures. (3) Sequential accident irradiations were performed both at 28 0 C and 70 0 C. (4) Age preconditioning was performed both sequentially and simultaneously. (5) Sequential aging irradiations were performed both at 27 0 C and 70 0 C. (6) Sequential aging exposures were performed using two sequences: (1) thermal followed by irradiation and (2) irradiation followed by thermal. We report both general trends applicable to a majority of the tested materials as well as specific results for each polymer. Our data base consists of ultimate tensile properties at the completion of the accident exposure for three XLPO and XLPE, five EPR and EPDM, two CSPE (HYPALON), one CPE, one VAMAC, one polydiallylphtalate, and one PPS material. We also report bend test results at completion of the accident exposures for two TEFZEL materials and permanent set after compression results for three EPR, one VAMAC, one BUNA N, one SILICONE, and one VITON material

Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells.

Science.gov (United States)

Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells S. Hunter, M. Rosen, M. Hoopes, H. Nichols, S. Jeffay, K. Chandler1, Integrated Systems Toxicology Division, National Health and Environmental Effects Research Labor...

Distribution and optical purity of methamphetamine found in toxic concentration in a civil aviation accident pilot fatality.

Science.gov (United States)

Chaturvedi, Arvind K; Cardona, Patrick S; Soper, John W; Canfield, Dennis V

2004-07-01

Toxicological evaluation of postmortem samples collected from a pilot involved in a unique fatal civil aircraft accident is described in this paper. A one-occupant airplane was substantially damaged upon colliding with terrain in poor visibility. Remains of the pilot were found outside the aircraft. Pathological examination revealed multiple blunt force injuries and vascular congestion. The fluorescence polarization immunoassay disclosed 8.0 microg/mL amphetamines in urine. Gas chromatographic/mass spectrometric analyses determined the presence of methamphetamine (1.13 microg/mL in blood and 59.2 microg/mL in urine) and amphetamine (0.022 microg/mL in blood and 1.50 microg/mL in urine). Methamphetamine was distributed throughout the body, including the brain. The amount of methamphetamine in gastric contents was 575-fold higher than that of amphetamine. The (+)- and (-)-forms of methamphetamine were present in equal proportions in gastric contents. The methamphetamine concentration found in blood was in the range sufficient to produce toxic effects, causing performance impairment.

Impacts of chemical modification on the toxicity of diverse nanocellulose materials to developing zebrafish.

Science.gov (United States)

Harper, Bryan J; Clendaniel, Alicea; Sinche, Federico; Way, Daniel; Hughes, Michael; Schardt, Jenna; Simonsen, John; Stefaniak, Aleksandr B; Harper, Stacey L

2016-06-01

Cellulose is an abundant and renewable resource currently being investigated for utility in nanomaterial form for various promising applications ranging from medical and pharmaceutical uses to mechanical reinforcement and biofuels. The utility of nanocellulose and wide implementation ensures increasing exposure to humans and the environment as nanocellulose-based technologies advance. Here, we investigate how differences in aspect ratio and changes to surface chemistry, as well as synthesis methods, influence the biocompatibility of nanocellulose materials using the embryonic zebrafish. Investigations into the toxicity of neutral, cationic and anionic surface functionalities revealed that surface chemistry had a minimal influence on the overall toxicity of nanocellulose materials. Higher aspect ratio cellulose nanofibers produced by mechanical homogenization were, in some cases, more toxic than other cellulose-based nanofibers or nanocrystals produced by chemical synthesis methods. Using fluorescently labeled nanocellulose we were able to show that nanocellulose uptake did occur in embryonic zebrafish during development. We conclude that the benign nature of nanocellulose materials makes them an ideal platform to systematically investigate the inherent surface features driving nanomaterial toxicity in order to create safer design principles for engineered nanoparticles.

Toxic chemical release inventory reporting form R and instructions. Revised 1992 version. Section 313 of the Emergency Planning and Community Right-to-Know Act

International Nuclear Information System (INIS)

1993-01-01

Reporting is required to provide the public with information on the releases of listed toxic chemicals in their communities and to provide EPA with release information to assist the Agency in determining the need for future regulations. Facilities must report the quantities of both routine and accidental releases of listed toxic chemicals, as well as the maximum amount of the listed toxic chemical on-site during the calendar year and the amount contained in wastes transferred off-site. These instructions supplement and elaborate on the requirements in the reporting rule (40 CFR Part 372). Together with the reporting rule, they constitute the reporting requirements. All references in these instructions are to sections in the reporting rule unless otherwise indicated

Source apportionment of toxic chemical pollutants at Trombay region

International Nuclear Information System (INIS)

Sahu, S.K.; Pandit, G.G.; Puranik, V.D.

2007-05-01

Anthropogenic activities like industrial production and transportation, a wide range of chemical pollutants such as trace and toxic metals, pesticides, polycyclic aromatic hydrocarbons etc. eventually find their way into various environmental compartments. One of the main issues of environmental pollution is the chemical composition of aerosols and their sources. In spite of all the efforts a considerable part of the atmospheric aerosol mass is still not accounted for. This report describes some of the activities of Environmental Assessment Division which are having direct relevance to the public health and regulatory bodies. Extensive studies were carried out in our laboratories for the Trombay site, over the years; on the organic as well as inorganic pollution in the environment to understand inter compartmental behaviour of these chemical pollutants. In this report an attempt has been made to collect different size fractionated ambient aerosols and to quantify the percentage contribution of each size fraction to the total aerosol mass. Subsequently, an effort has been made for chemical characterization (inorganic, organic and carbon content) of these particulate matter using different analytical techniques. The comprehensive data set on chemical characterization of particulate matter thus generated is being used with receptor modeling techniques to identify the possible sources contributing to the observed concentrations of the measured pollutants. The use of this comprehensive data set in receptor modeling has been helpful in distinguishing the source types in a better way. Receptor modeling techniques are powerful tools that can be used to locate sources of pollutants to the atmosphere. The major advantage of the receptor models is that actual ambient data are used to apportion source contributions, negating the need for dispersion calculations. Pollution sources affecting the sampling site were statistically identified using varimax rotated factor analysis of

Exploring the Q-marker of "sweat soaking method" processed radix Wikstroemia indica: Based on the "effect-toxicity-chemicals" study.

Science.gov (United States)

Feng, Guo; Chen, Yun-Long; Li, Wei; Li, Lai-Lai; Wu, Zeng-Guang; Wu, Zi-Jun; Hai, Yue; Zhang, Si-Chao; Zheng, Chuan-Qi; Liu, Chang-Xiao; He, Xin

2018-06-01

Radix Wikstroemia indica (RWI), named "Liao Ge Wang" in Chinese, is a kind of toxic Chinese herbal medicine (CHM) commonly used in Miao nationality of South China. "Sweat soaking method" processed RWI could effectively decrease its toxicity and preserve therapeutic effect. However, the underlying mechanism of processing is still not clear, and the Q-markers database for processed RWI has not been established. Our study is to investigate and establish the quality evaluation system and potential Q-markers based on "effect-toxicity-chemicals" relationship of RWI for quality/safety assessment of "sweat soaking method" processing. The variation of RWI in efficacy and toxicity before and after processing was investigated by pharmacological and toxicological studies. Cytotoxicity test was used to screen the cytotoxicity of components in RWI. The material basis in ethanol extract of raw and processed RWI was studied by UPLC-Q-TOF/MS. And the potential Q-markers were analyzed and predicted according to "effect-toxicity-chemical" relationship. RWI was processed by "sweat soaking method", which could preserve efficacy and reduce toxicity. Raw RWI and processed RWI did not show significant difference on the antinociceptive and anti-inflammatory effect, however, the injury of liver and kidney by processed RWI was much weaker than that by raw RWI. The 20 compounds were identified from the ethanol extract of raw product and processed product of RWI using UPLC-Q-TOF/MS, including daphnoretin, emodin, triumbelletin, dibutyl phthalate, Methyl Paraben, YH-10 + OH and matairesinol, arctigenin, kaempferol and physcion. Furthermore, 3 diterpenoids (YH-10, YH-12 and YH-15) were proved to possess the high toxicity and decreased by 48%, 44% and 65%, respectively, which could be regarded as the potential Q-markers for quality/safety assessment of "sweat soaking method" processed RWI. A Q-marker database of processed RWI by "sweat soaking method" was established according to the results

Toxic Effects of Peracetic Acid Used as a Chemical Weapon During Workers Riots

International Nuclear Information System (INIS)

Jovic-Stosic, J.; Todorovic, V.; Segrt, Z.

2007-01-01

Peracetic acid (PAA) is a mixture of acetic acid and hydrogen peroxide, often used as antimicrobial agent on food processing equipment. It may explosively decompose on shock, friction or concussion. PAA is a strong oxidant, corrosive to the eyes, skin, respiratory and digestive tract. Depending on concentration, contact may cause severe burns of the skin or the eyes, and inhalation may cause lung edema. We report toxic effects of PAA used as a chemical weapon in workers riots. Group of workers attacked the security guards in beverage plant, throwing out beer bottles filled with PAA. Bottles exploded, producing irritant mists and fumes, and splashing some of the guards with acid. After about 20 minutes of exposure in the closed space, 30 persons were transported to the emergency room; 22 of them were transferred to the hospital. After the initial treatment, 10 patients were admitted for further treatment. The symptoms of exposure included burning sensation and pain of the eyes, throat and skin, cough and shortness of breath. Effects on the eyes included redness and corneal erosions. Pulmonary disturbances were prolonged expirium and wheezing by auscultation, and hypoxemia. Skin burns were ranged as grade I-III. Treatment included rinse of eyes and skin, systemic therapy with corticosteroids, beta adrenergic drugs and theophylline. Surgical treatment was necessary in grade III skin burns. A variety of common industrial chemicals may be misused as a chemical weapon. We point out the hazards of serious toxic effects of PAA if used in riots or terrorists attacks. (author)

Panel discussion: Which severe accident chemistry topics most deserve further research?

International Nuclear Information System (INIS)

Bergeron, K.D.

1988-01-01

A severe accident would involve so many species and chemical environments within the plant that detailed description of all the chemical reactions and chemistry-related processes is currently not practical or even possible. Thus it is necessary to select for consideration those phenomena which might be most important. The panel will discuss which severe accident chemistry topics most deserve further research

1976 Hanford americium-exposure incident: accident description

International Nuclear Information System (INIS)

McMurray, B.J.

1982-01-01

An accident is described, involving the explosion of an ion-exchange column containing about 100 g of 241 Am. A chemical operator was injured in this accident, receiving acid burns and superficial cuts on the upper part of his body. From 1 to 5 curies of 241 Am is estimated to have been deposited on the injured worker and on his clothing

Dust resuspension and transport modeling for loss of vacuum accidents

International Nuclear Information System (INIS)

Humrickhouse, P.W.; Corradini, M.L.; Sharpe, J.P.

2007-01-01

Plasma surface interactions in tokamaks are known to create significant quantities of dust, which settles onto surfaces and accumulates in the vacuum vessel. In ITER, a loss of vacuum accident may result in the release of dust which will be radioactive and/or toxic, and provides increased surface area for chemical reactions or dust explosion. A new method of analysis has been developed for modeling dust resuspension and transport in loss of vacuum accidents. The aerosol dynamic equation is solved via the user defined scalar (UDS) capability in the commercial CFD code Fluent. Fluent solves up to 50 generic transport equations for user defined scalars, and allows customization of terms in these equations through user defined functions (UDF). This allows calculation of diffusion coefficients based on local flow properties, inclusion of body forces such as gravity and thermophoresis in the convection term, and user defined source terms. The code accurately reproduces analytical solutions for aerosol deposition in simple laminar flows with diffusion and gravitational settling. Models for dust resuspension are evaluated, and code results are compared to available resuspension data, including data from the Toroidal Dust Mobilization Experiment (TDMX) at the Idaho National Laboratory. Extension to polydisperse aerosols and inclusion of coagulation effects is also discussed. (orig.)

Toxic substances handbook

Science.gov (United States)

Junod, T. L.

1979-01-01

Handbook, published in conjunction with Toxic Substances Alert Program at NASA Lewis Research Center, profiles 187 toxic chemicals in their relatively pure states and include 27 known or suspected carcinogens.

CHEMICAL COMPOSITION AND TOXICITY OF CITRUS ESSENTIAL OILS ON Dysmicoccus brevipes (HEMIPTERA: PSEUDOCOCCIDAE)

OpenAIRE

MARTINS, GISELE DOS SANTOS OLIVEIRA; ZAGO, HUGO BOLSONI; COSTA, ADILSON VIDAL; ARAUJO JUNIOR, LUIS MOREIRA DE; CARVALHO, JOSÉ ROMÁRIO DE

2017-01-01

ABSTRACT The insect Dysmicoccus brevipes (Hemiptera: Pseudococcidae) has been reported as an important pest for several crops, especially coffee. The citrus essential oils can be obtained as by-products of the citrus-processing industry and have been tested as an alternative to control different insect groups. Therefore, the objective of this work was to determine the chemical composition and evaluate the toxicity of commercial sweet orange (Citrus sinensis), bitter orange (Citrus aurantium) ...

Predicting Developmental Toxicity of ToxCast Phase I Chemicals Using Human Embryonic Stem Cells and Metabolomics

Science.gov (United States)

EPA’s ToxRefDB contains prenatal guideline study data from rats and rabbits for over 240 chemicals that overlap with the ToxCast in vitro high throughput screening project. A subset of these compounds were tested in Stemina Biomarker Discovery's developmental toxicity platform, a...

Hazards to nuclear plants from surface traffic accidents

International Nuclear Information System (INIS)

Hornyik, K.

1975-01-01

Analytic models have been developed for evaluating hazards to nuclear plants from hazardous-materials accidents in the vicinity of the plant. In particular, these models permit the evaluation of hazards from such accidents occurring on surface traffic routes near the plant. The analysis uses statistical information on accident rates, traffic frequency, and cargo-size distribution along with parameters describing properties of the hazardous cargo, plant design, and atmospheric conditions, to arrive at a conservative estimate of the annual probability of a catastrophic event. Two of the major effects associated with hazardous-materials accidents, explosion and release of toxic vapors, are treated by a common formalism which can be readily applied to any given case by means of a graphic procedure. As an example, for a typical case it is found that railroad shipments of chlorine in 55-ton tank cars constitute a greater hazard to a nearby nuclear plant than equally frequent rail shipments of explosives in amounts of 10 tons. 11 references. (U.S.)

Overview of Chronic Oral Toxicity Values for Chemicals Present in Hydraulic Fracturing Fluids, Flowback and Produced Waters

Science.gov (United States)

as part of EPA's Hydraulic Fracturing Drinking Water Assessment, EPA is summarizing existing toxicity data for chemicals reported to be used in hydraulic fracturing fluids and/or found in flowback or produced waters from hydraulically fractured wells

Proteomic Signatures of the Zebrafish (Danio rerio) Embryo: Sensitivity and Specificity in Toxicity Assessment of Chemicals.

Science.gov (United States)

Hanisch, Karen; Küster, Eberhard; Altenburger, Rolf; Gündel, Ulrike

2010-01-01

Studies using embryos of the zebrafish Danio rerio (DarT) instead of adult fish for characterising the (eco-) toxic potential of chemicals have been proposed as animal replacing methods. Effect analysis at the molecular level might enhance sensitivity, specificity, and predictive value of the embryonal studies. The present paper aimed to test the potential of toxicoproteomics with zebrafish eleutheroembryos for sensitive and specific toxicity assessment. 2-DE-based toxicoproteomics was performed applying low-dose (EC(10)) exposure for 48 h with three-model substances Rotenone, 4,6-dinitro-o-cresol (DNOC) and Diclofenac. By multivariate "pattern-only" PCA and univariate statistical analyses, alterations in the embryonal proteome were detectable in nonetheless visibly intact organisms and treatment with the three substances was distinguishable at the molecular level. Toxicoproteomics enabled the enhancement of sensitivity and specificity of the embryonal toxicity assay and bear the potency to identify protein markers serving as general stress markers and early diagnosis of toxic stress.

Inferring the chemical form of 137Cs deposited by the Fukushima Dai-ichi Nuclear Power Plant accident by measuring (137)Cs incorporated into needle leaves and male cones of Japanese cedar trees.

Science.gov (United States)

Kanasashi, Tsutomu; Takenaka, Chisato; Sugiura, Yuki

2016-05-15

We hypothesized that the water-soluble (ionic) and water-insoluble (stable) radiocesium from the initial fallout of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident was distributed in various proportions in the surrounding areas and that this distribution was reflected in the trees that suffered deposition from the initial fallout. This study attempted to evaluate local variations in the chemical form of (137)Cs derived from the initial fallout of the FDNPP accident and whether its chemical form affected the radiocesium concentration in the tissues currently growing in trees, even after the initial fallout ceased. For these estimations, the ratio between the (137)Cs concentration in Cryptomeria japonica needle leaves in the tree crown, which existed before the FDNPP accident and subsequently directly exposed to the initial fallout ((137)Cs pre-accident N), and the amount of (137)Cs in the initial fallout itself ((137)Cs fallout) was determined ((137)Cs pre-accident N/(137)Cs fallout) at 66 sites. In addition, the (137)Cs ratios between the male cones produced in 2012 ((137)Cs male cone) and needle leaves that had elongated in the spring of 2011 ((137)Cs 2011N) was determined at 82 sites ((137)Cs male cone/(137) Cs 2011N). Most of the sites with lower (137)Cs pre-accident N /(137)Cs fallout ratios were distributed in eastern Fukushima, relatively close to the Pacific Ocean coastline. Lower (137)Cs pre-accident N/(137)Cs fallout and higher (137)Cs malecone/(137)Cs 2011N were found to be associated with higher proportions of (137)Cs in ionic forms. These observations are consistent with the hypothesis, and likely reflect regional variations in the chemical form of the deposited radiocesium. Copyright © 2016 Elsevier B.V. All rights reserved.

A toxicity reduction evaluation for an oily waste treatment plant exhibiting episodic effluent toxicity.

Science.gov (United States)

Erten-Unal, M; Gelderloos, A B; Hughes, J S

1998-07-30

A Toxicity Reduction Evaluation (TRE) was conducted on the oily wastewater treatment plant (Plant) at a Naval Fuel Depot. The Plant treats ship and ballast wastes, berm water from fuel storage areas and wastes generated in the fuel reclamation plant utilizing physical/chemical treatment processes. In the first period of the project (Period I), the TRE included chemical characterization of the plant wastewaters, monitoring the final effluent for acute toxicity and a thorough evaluation of each treatment process and Plant operating procedures. Toxicity Identification Evaluation (TIE) procedures were performed as part of the overall TRE to characterize and identify possible sources of toxicity. Several difficulties were encountered because the effluent was saline, test organisms were marine species and toxicity was sporadic and unpredictable. The treatability approach utilizing enhancements, improved housekeeping, and operational changes produced substantial reductions in the acute toxicity of the final effluent. In the second period (Period II), additional acute toxicity testing and chemical characterization were performed through the Plant to assess the long-term effects of major unit process improvements for the removal of toxicity. The TIE procedures were also modified for saline wastewaters to focus on suspected class of toxicants such as surfactants. The TRE was successful in reducing acute toxicity of the final effluent through process improvements and operational modifications. The results indicated that the cause of toxicity was most likely due to combination of pollutants (matrix effect) rather than a single pollutant.

Data gaps in toxicity testing of chemicals allowed in food in the United States.

Science.gov (United States)

Neltner, Thomas G; Alger, Heather M; Leonard, Jack E; Maffini, Maricel V

2013-12-01

In the United States, chemical additives cannot be used in food without an affirmative determination that their use is safe by FDA or additive manufacturer. Feeding toxicology studies designed to estimate the amount of a chemical additive that can be eaten safely provide the most relevant information. We analyze how many chemical additives allowed in human food have feeding toxicology studies in three toxicological information sources including the U.S. Food and Drug Administration's (FDA) database. Less than 38% of FDA-regulated additives have a published feeding study. For chemicals directly added to food, 21.6% have feeding studies necessary to estimate a safe level of exposure and 6.7% have reproductive or developmental toxicity data in FDA's database. A program is needed to fill these significant knowledge gaps by using in vitro and in silico methods complemented with targeted in vivo studies to ensure public health is protected. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - final report

International Nuclear Information System (INIS)

Gerton, R.E.

1997-01-01

On May 14, 1997, at 7:53 p.m. (PDT), a chemical explosion occur-red in Tank A- 109 in Room 40 of the Plutonium Reclamation Facility (Facility) located in the 200 West Area of the Hanford Site, approximately 30 miles north of Richland, Washington. The inactive processing Facility is part of the Plutonium Finishing Plant (PFP). On May 16, 1997, Lloyd L. Piper, Deputy Manager, acting for John D. Wagoner, Manager, U.S. Department of Energy (DOE), Richland Operations Office (RL), formally established an Accident Investigation Board (Board) to investigate the explosion in accordance with DOE Order 225. 1, Accident Investigations. The Board commenced its investigation on May 15, 1997, completed the investigation on July 2, 1997, and submitted its findings to the RL Manager on July 26, 1997. The scope of the Board's investigation was to review and analyze the circumstances of the events that led to the explosion; to analyze facts and to determine the causes of the accident; and to develop conclusions and judgments of need that may help prevent a recurrence of the accident. The scope also included the application of lessons learned from similar accidents within DOE. In addition to this detailed report, a companion document has also been prepared that provides a concise summary of the facts and conclusions of this report, with an emphasis on management issues (DOE/RL-97-63)

Strategy generation in accident management support

International Nuclear Information System (INIS)

Sirola, M.

1995-01-01

An increased interest for research in the field of Accident Management can be noted. Several international programmes have been started in order to be able to understand the basic physical and chemical phenomena in accident conditions. A feasibility study has shown that it would be possible to design and develop a computerized support system for plant staff in accident situations. To achieve this goal the Halden Project has initiated a research programme on Computerized Accident Management Support (CAMS project). The aim is to utilize the capabilities of computerized tools to support the plant staff during the various accident stages. The system will include identification of the accident state, assessment of the future development of the accident and planning of accident mitigation strategies. A prototype is developed to support operators and the Technical Support Centre in decision making during serious accident in nuclear power plants. A rule based system has been built to take care of the strategy generation. This system assists plant personnel in planning control proposals and mitigation strategies from normal operation to severe accident conditions. The ideal of a safety objective tree and knowledge from the emergency procedures have been used. Future prediction requires good state identification of the plant status and some knowledge about the history of some critical variables. The information needs to be validated as well. Accurate calculations in simulators and a large database including all important information form the plant will help the strategy planning. (author). 12 refs, 2 figs

Human Pluripotent Stem Cell-Based Assay Predicts Developmental Toxicity Potential of ToxCast Chemicals (ACT meeting)

Science.gov (United States)

Worldwide initiatives to screen for toxicity potential among the thousands of chemicals currently in use require inexpensive and high-throughput in vitro models to meet their goals. The devTOX quickPredict platform is an in vitro human pluripotent stem cell-based assay used to as...

[Characterization of severe acute occupational poisoning accidents in China between 1989 and 2003].

Science.gov (United States)

Zhang, Min; Li, Tao; Wang, Huan-Qiang; Wang, Hong-Fei; Chen, Shu-Yang; Du, Xie-Yi; Zhang, Shuang; Qin, Jian

2006-12-01

To analyze severe acute occupational poisoning accidents reported in China between 1989 and 2003, and to study the characteristics of severe acute occupational poisoning accidents and provide scientific evidences for prevention and control strategies. The data from the national occupational poisoning case reporting system were analyzed with descriptive methods. (1) There were 506 acute severe occupational poisoning accidents for 15 years with 4 657 workers poisoned. The total poisoning rate was 54.8%, and the total mortality was 16.5%. The average poisoning age was (31.9 +/- 9.8) years old and the average death age was (33.7 +/- 10.3) years old. The poisoning accidents occurred more in men than in women. (2) There were more than 112 chemicals which caused these poisoning accidents. Most of the accidents caused by hydrogen sulfide, carbon monoxide, benzene and homologs, metal and metalloid and carbon dioxide, and the types of chemicals varied in different types of industries. (3) The accidents mainly occurred in chemical industry, manufacture, water disposal industry, mining and construction industry, and the risk was higher in some jobs than others, such as cleanout, machine maintenance and repair, production, mine and digging. The accidents occurred more frequently from April to August each year. (1) The control over the severe acute occupational poisoning is urgent. (2) The trend of the characteristics of severe acute occupational poisoning accidents is centralized in the high risk industries, poisons and jobs. (3) The characteristics of the accidents varied in different types of industries. (4) It is the key point to strengthen the supervision on poisoning.

Estimation of toxicity using the Toxicity Estimation Software Tool (TEST)

Science.gov (United States)

Tens of thousands of chemicals are currently in commerce, and hundreds more are introduced every year. Since experimental measurements of toxicity are extremely time consuming and expensive, it is imperative that alternative methods to estimate toxicity are developed.

Estimating the threshold levels of uranium and fluorine for the development of pulmonitis and toxic lung edema resultant from accidents involving uranium hexafluoride release

International Nuclear Information System (INIS)

Gasteva, G.N.; Antipin, E.B.; Bad'in, V.I.; Molokanov, A.A.; Mordasheva, V.V.; Mirkhajdarov, A.Kh.; Sorokin, A.V.; Savinova, I.A.

1999-01-01

Threshold doses of uranium and fluorine for the development of pulmonitis and toxic edema of the lung with lethal outcome are estimated. The levels of UF 6 entry under emergency conditions are evaluated and bronchopulmonary disease is described in subjects involved in three accidents with UF 6 release which occurred in the seventies and eighties, as shown by records. The results deny the previous assumption on the leading role of uranium in a single exposure to uranium hexafluoride. Fluorine ion triggering the mechanism of reactions in systems which determine the disease outcome is vitally important [ru

Chernobyl and Fukushima nuclear accidents: what has changed in the use of atmospheric dispersion modeling?

International Nuclear Information System (INIS)

Benamrane, Y.; Wybo, J.-L.; Armand, P.

2013-01-01

The threat of a major accidental or deliberate event that would lead to hazardous materials emission in the atmosphere is a great cause of concern to societies. This is due to the potential large scale of casualties and damages that could result from the release of explosive, flammable or toxic gases from industrial plants or transport accidents, radioactive material from nuclear power plants (NPPs), and chemical, biological, radiological or nuclear (CBRN) terrorist attacks. In order to respond efficiently to such events, emergency services and authorities resort to appropriate planning and organizational patterns. This paper focuses on the use of atmospheric dispersion modeling (ADM) as a support tool for emergency planning and response, to assess the propagation of the hazardous cloud and thereby, take adequate counter measures. This paper intends to illustrate the noticeable evolution in the operational use of ADM tools over 25 y and especially in emergency situations. This study is based on data available in scientific publications and exemplified using the two most severe nuclear accidents: Chernobyl (1986) and Fukushima (2011). It appears that during the Chernobyl accident, ADM were used few days after the beginning of the accident mainly in a diagnosis approach trying to reconstruct what happened, whereas 25 y later, ADM was also used during the first days and weeks of the Fukushima accident to anticipate the potentially threatened areas. We argue that the recent developments in ADM tools play an increasing role in emergencies and crises management, by supporting stakeholders in anticipating, monitoring and assessing post-event damages. However, despite technological evolutions, its prognostic and diagnostic use in emergency situations still arise many issues. -- Highlights: • Study of atmospheric dispersion modeling use during nuclear accidents. • ADM tools were mainly used in a diagnosis approach during Chernobyl accident. • ADM tools were also used

The influence of chemistry on severe accident phenomena in integral tests

International Nuclear Information System (INIS)

Hobbins, R.R.; Osetek, D.J.; Hagrman, D.L.

1988-01-01

The influence of chemical processes on severe accident phenomena in integral tests is reviewed and recommendations for areas of additional work are made. The results reviewed include those from tests conducted in the in-pile facilities at ACRR, PBF, and TREAT and the TMI-2 accident. Progress has been made in understanding the influence of chemistry on important severe accident phenomena such as core melt progression, hydrogen generation, aerosol generation and transport, and fission product release and transport (including revaporization). An example is the chemistry of volatile fission products, especially iodine and tellurium. Areas where understanding is inadequate are also apparent, such as chemical interactions between fission product vapors and aerosols. Influential chemical processes reviewed include oxidation by steam and interactions among control, structural, fuel, fission product, and aerosol materials

Chemistry of fission product iodine under nuclear reactor accident conditions

International Nuclear Information System (INIS)

Malinauskas, A.P.; Bell, J.T.

1986-01-01

The radioisotopes of iodine are generally acknowledged to be the species whose release into the biosphere as a result of a nuclear reactor accident is of the greatest concern. In the course of its release, the fission product is subjected to differing chemical environments; these can alter the physicochemical form of the fission product and thus modify the manner and extent to which release occurs. Both the chemical environments which are characteristic of reactor accidents and their effect in determining physical and chemical form of fission product iodine have been studied extensively, and are reviewed in this report. 76 refs

Interaction of radionuclides in severe accident conditions

International Nuclear Information System (INIS)

Nagrale, Dhanesh B.; Bera, Subrata; Deo, Anuj Kumar; Paul, U.K.; Prasad, M.; Gaikwad, A.J.

2015-01-01

Nuclear power plants are designed with inherent engineering safety systems and associated operational procedures that provide an in-depth defence against accidents. Radionuclides such as Iodine, Cesium, Tellurium, Barium, Strontium, Rubidium, Molybdenum and many others may get released during a severe accident. Among these, Iodine, one of the fission products, behaviour is significant for the analysis of severe accident consequences because iodine is a chemically more active to the potential components released to the environment. During severe accident, Iodine is released and transported in aqueous, organic and inorganic forms. Iodine release from fuel, iodine transport in primary coolant system, containment, and reaction with control rods are some of the important phases in a severe accident scenario. The behaviour of iodine is governed by aerosol physics, depletion mechanisms gravitational settling, diffusiophoresis and thermophoresis. The presence of gaseous organic compounds and oxidizing compounds on iodine, reactions of aerosol iodine with boron and formation of cesium iodide which results in more volatile iodine release in containment play significant roles. Water radiolysis products due to presence of dissolved impurities, chloride ions, organic impurities should be considered while calculating iodine release. Containment filtered venting system (CFVS) consists of venturi scrubber and a scrubber tank which is dosed with NaOH and NaS_2O_3 in water where iodine will react with the chemicals and convert into NaI and Na_2SO_4. This paper elaborates the issues with respect to interaction of radionuclides and its consideration in modeling of severe accident. (author)

Links between operating experience feedback of industrial accidents and nuclear safety

International Nuclear Information System (INIS)

Eury, S.P.

2012-01-01

Since 1992, the bureau for analysis of industrial risks and pollutions (BARPI) collects, analyzes and publishes information on industrial accidents. The ARIA database lists over 40.000 accidents or incidents, most of which occurred in French classified facilities (ICPE). Events occurring in nuclear facilities are rarely reported in ARIA because they are reported in other databases. This paper describes the process of selection, characterization and review of these accidents, as well as the following consultation with industry trade groups. It is essential to publicize widely the lessons learned from analyzing industrial accidents. To this end, a web site (www.aria.developpement-durable.gouv.fr) gives free access to the accidents summaries, detailed sheets, studies, etc. to professionals and the general public. In addition, the accidents descriptions and characteristics serve as inputs to new regulation projects or risk analyses. Finally, the question of the links between operating experience feedback of industrial accidents and nuclear safety is explored: if the rigorous and well-documented methods of experience feedback in the nuclear field certainly set an example for other activities, nuclear safety can also benefit from inputs coming from the vast diversity of accidents arisen into industrial facilities because of common grounds. Among these common grounds we can find: -) the fuel cycle facilities use many chemicals and chemical processes that are also used by chemical industries; -) the problems resulting from the ageing of equipment affect both heavy and nuclear industries; -) the risk of hydrogen explosion; -) the risk of ammonia, ammonia is a gas used by nuclear power plants as an ingredient in the onsite production of mono-chloramine and ammonia is involved in numerous accidents in the industry: at least 900 entries can be found in the ARIA database. The paper is followed by the slides of the presentation

[Labor accidents involving the eyes: assessment of occupational risks involving nursing workers].

Science.gov (United States)

de Almeida, Cristiana Brasil; Pagliuca, Lorita Marlena Freitag; Leite, Ana Lourdes Almeida e Silva

2005-01-01

The study aimed at identifying nursing workers who were victims of eye accidents and the type of accident; describing the measures taken and proposing Health Education methods. A descriptive and exploratory study was carried out at a public maternity hospital from September 2002 to January 2003. Data were collected through direct observation of the environment and interviews with workers. Subjects were ten professionals (one nurse, two technicians and seven nursing auxiliaries) who were victims of work accidents involving the eye. The accidents were grouped according to the type of material that caused the trauma: chemical substances (4), medication (3), mechanical trauma (1), scalp (1) and urine (1). The results reveal that hospital workers are vulnerable to labor accidents because the environment presents biological, chemical and physical risks. An important step to prevent the occurrence of new accidents would be the prevention of human mistakes through permanent training and the use of protection glasses.

Applicability of the fish embryo acute toxicity (FET) test (OECD 236) in the regulatory context of Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH).

NARCIS (Netherlands)

Sobanska, Marta; Scholz, Stefan; Nyman, Anna-Maija; Cesnaitis, Romanas; Gutierrez Alonso, Simon; Klüver, Nils; Kühne, Ralph; Tyle, Henrik; de Knecht, Joop; Dang, Zhichao; Lundbergh, Ivar; Carlon, Claudio; De Coen, Wim

In 2013 the Organisation for Economic Co-operation and Development (OECD) test guideline (236) for fish embryo acute toxicity (FET) was adopted. It determines the acute toxicity of chemicals to embryonic fish. Previous studies show a good correlation of FET with the standard acute fish toxicity

Chemical interactions between aerosols and vapors in the primary circuit of an LWR during a severe accident

International Nuclear Information System (INIS)

Wheatley, C.J.

1988-01-01

Aerosol formation, agglomeration, convection and deposition within the primary circuit of an LWR during a severe accident significantly affect the transport of fission products, even though they may compose only a small fraction of the aerosol material. Intra-particle and vapor chemical interactions are important to this through mass transfer between the aerosol and vapor. The authors will describe a model that attempts to account for these processes and of the two-way coupling that exists with the thermal hydraulics. They will discuss what agglomeration and deposition mechanisms must be included, alternatives for treating intra-particle chemical interactions, mechanisms of aerosol formation, and methods for solving the resulting equations. Results will be presented that illustrate the importance of treating the two-way coupling and the extent to which disequilibrium between the aerosol and vapor affects fission product behavior

Health and environmental threats associated with the destruction of chemical weapons.

Science.gov (United States)

Matousek, Jirí

2006-09-01

Still existing arsenals of chemical weapons (CW) pose not only security threats for possible use in hostilities by state actors or misuse by terrorists but also safety threats to humans and biota due to leakages and possible accidents. The Chemical Weapons Convention (CWC) commits the States Parties (SPs) to destroy CW using technologies taking into consideration human health and environmental protection. It does not allow methods, routinely used up to the 1970s, such as earth burial, open-pit burning, and sea dumping. Long-term health and environmental threats and some accidents that have already occurred in the known localities of the sea-dumped and earth-buried arsenals of Nazi-German armed forces in the Baltic Region and of Imperial Japanese forces in the Far East Region are analyzed according to the impact of major CW and ammunition types (i.e., sulfur mustard--HD, tabun--GA, arsenicals--DA, DC, DM, arsine oil, and chloroacetophenone--CN). Any possible operations and handling with CW envisaged by the CWC as well as their verification are summarized taking into account the health threat they pose. CW and toxic armament waste to be destroyed and applied technologies (both developed and under current use in operational CW destruction facilities [CWDF]) are reviewed as are systems of health safety and environmental protection of the destruction/demilitarization stems from the extraordinary high toxicity of supertoxic lethal agents in man and biota. Problems of currently used Russian and U.S. standards for maximum allowable workplace concentrations and general population limits and possibilities of their determination by available analytical instrumentation are discussed.

Chemical and biological properties of toxic metals and use of chelating agents for the pharmacological treatment of metal poisoning

Energy Technology Data Exchange (ETDEWEB)

Sinicropi, Maria Stefania; Caruso, Anna [University of Calabria, Department of Pharmaceutical Sciences, Rende (Italy); Amantea, Diana [University of Calabria, Department of Pharmacobiology, Rende (Italy); Saturnino, Carmela [University of Salerno, Department of Pharmaceutical Sciences, Fisciano (Italy)

2010-07-15

Exposure to toxic metals is a well-known problem in industrialized countries. Metals interfere with a number of physiological processes, including central nervous system (CNS), haematopoietic, hepatic and renal functions. In the evaluation of the toxicity of a particular metal it is crucial to consider many parameters: chemical forms (elemental, organic or inorganic), binding capability, presence of specific proteins that selectively bind metals, etc. Medical treatment of acute and chronic metal toxicity is provided by chelating agents, namely organic compounds capable of interacting with metal ions to form structures called chelates. The present review attempts to provide updated information about the mechanisms, the cellular targets and the effects of toxic metals. (orig.)

Toxic effects exerted on methanogenic, nitrifying and denitrifying bacteria by chemicals used in a milk analysis laboratory

NARCIS (Netherlands)

Lopez-Fiuza, J.; Buys, B.; Mosquera-Corral, A.; Omil, F.; Mendez, R.

2002-01-01

The toxic effects caused by the chemicals contained in wastewaters generated by laboratories involved in raw milk analyses were assessed using batch assays. These assays were carried out separately with methanogenic, ammonium-oxidizing, nitrite-oxidizing and denitrifying bacteria. Since sodium azide

Windows of sensitivity to toxic chemicals in the motor effects development.

Science.gov (United States)

Ingber, Susan Z; Pohl, Hana R

2016-02-01

Many chemicals currently used are known to elicit nervous system effects. In addition, approximately 2000 new chemicals introduced annually have not yet undergone neurotoxicity testing. This review concentrated on motor development effects associated with exposure to environmental neurotoxicants to help identify critical windows of exposure and begin to assess data needs based on a subset of chemicals thoroughly reviewed by the Agency for Toxic Substances and Disease Registry (ATSDR) in Toxicological Profiles and Addenda. Multiple windows of sensitivity were identified that differed based on the maturity level of the neurological system at the time of exposure, as well as dose and exposure duration. Similar but distinct windows were found for both motor activity (GD 8-17 [rats], GD 12-14 and PND 3-10 [mice]) and motor function performance (insufficient data for rats, GD 12-17 [mice]). Identifying specific windows of sensitivity in animal studies was hampered by study designs oriented towards detection of neurotoxicity that occurred at any time throughout the developmental process. In conclusion, while this investigation identified some critical exposure windows for motor development effects, it demonstrates a need for more acute duration exposure studies based on neurodevelopmental windows, particularly during the exposure periods identified in this review. Published by Elsevier Inc.

The yellow cake accident at the Ezeiza Airport

International Nuclear Information System (INIS)

Rodriguez, C.E.; Puntarulo, L.J.; Canibano, J.A.

1989-01-01

In January 1987 several drums containing yellow cake fell from about six meters during the loading operation of a Boeing 747 T-100 cargo aircraft. As a result of the accident, about 50% of the 38 drums involved lost their lids and a fraction of the radioactive content was released on an area of about 200 meters squared. Small amounts of yellow cake were dispersed down wind until about 100 meters from the accident place. The shipment was prepared for transport in standard 200 liter steel drums fulfilling the applicable Transport Regulations and the accident was the consequence of an erroneous operation during the cargo associated with a mechanical failure of the cargo lift. In order to avoid human contamination, immediate action was taken by the airport emergency team and in the meantime, the specialized groups of the National Atomic Energy Commission and the Federal Fire Brigades, were convened to take care of the decontamination and radiological evaluation problems. This paper describes the accidental sequences, the accident scenery, the countermeasures taken, the recovery and decontamination actions, and finally, as a conclusion, a brief description of the toxic and radiological aspects of the accident's mode

Differential reconstructed gene interaction networks for deriving toxicity threshold in chemical risk assessment.

Science.gov (United States)

Yang, Yi; Maxwell, Andrew; Zhang, Xiaowei; Wang, Nan; Perkins, Edward J; Zhang, Chaoyang; Gong, Ping

2013-01-01

Pathway alterations reflected as changes in gene expression regulation and gene interaction can result from cellular exposure to toxicants. Such information is often used to elucidate toxicological modes of action. From a risk assessment perspective, alterations in biological pathways are a rich resource for setting toxicant thresholds, which may be more sensitive and mechanism-informed than traditional toxicity endpoints. Here we developed a novel differential networks (DNs) approach to connect pathway perturbation with toxicity threshold setting. Our DNs approach consists of 6 steps: time-series gene expression data collection, identification of altered genes, gene interaction network reconstruction, differential edge inference, mapping of genes with differential edges to pathways, and establishment of causal relationships between chemical concentration and perturbed pathways. A one-sample Gaussian process model and a linear regression model were used to identify genes that exhibited significant profile changes across an entire time course and between treatments, respectively. Interaction networks of differentially expressed (DE) genes were reconstructed for different treatments using a state space model and then compared to infer differential edges/interactions. DE genes possessing differential edges were mapped to biological pathways in databases such as KEGG pathways. Using the DNs approach, we analyzed a time-series Escherichia coli live cell gene expression dataset consisting of 4 treatments (control, 10, 100, 1000 mg/L naphthenic acids, NAs) and 18 time points. Through comparison of reconstructed networks and construction of differential networks, 80 genes were identified as DE genes with a significant number of differential edges, and 22 KEGG pathways were altered in a concentration-dependent manner. Some of these pathways were perturbed to a degree as high as 70% even at the lowest exposure concentration, implying a high sensitivity of our DNs approach

Distributed Structure Searchable Toxicity

Data.gov (United States)

U.S. Environmental Protection Agency — The Distributed Structure Searchable Toxicity (DSSTox) online resource provides high quality chemical structures and annotations in association with toxicity data....

Chernobyl and Fukushima nuclear accidents: what has changed in the use of atmospheric dispersion modeling?

Science.gov (United States)

Benamrane, Y; Wybo, J-L; Armand, P

2013-12-01

The threat of a major accidental or deliberate event that would lead to hazardous materials emission in the atmosphere is a great cause of concern to societies. This is due to the potential large scale of casualties and damages that could result from the release of explosive, flammable or toxic gases from industrial plants or transport accidents, radioactive material from nuclear power plants (NPPs), and chemical, biological, radiological or nuclear (CBRN) terrorist attacks. In order to respond efficiently to such events, emergency services and authorities resort to appropriate planning and organizational patterns. This paper focuses on the use of atmospheric dispersion modeling (ADM) as a support tool for emergency planning and response, to assess the propagation of the hazardous cloud and thereby, take adequate counter measures. This paper intends to illustrate the noticeable evolution in the operational use of ADM tools over 25 y and especially in emergency situations. This study is based on data available in scientific publications and exemplified using the two most severe nuclear accidents: Chernobyl (1986) and Fukushima (2011). It appears that during the Chernobyl accident, ADM were used few days after the beginning of the accident mainly in a diagnosis approach trying to reconstruct what happened, whereas 25 y later, ADM was also used during the first days and weeks of the Fukushima accident to anticipate the potentially threatened areas. We argue that the recent developments in ADM tools play an increasing role in emergencies and crises management, by supporting stakeholders in anticipating, monitoring and assessing post-event damages. However, despite technological evolutions, its prognostic and diagnostic use in emergency situations still arise many issues. Copyright © 2013 Elsevier Ltd. All rights reserved.

Allowable shipment frequencies for the transport of toxic gases near nuclear power plants

International Nuclear Information System (INIS)

Bennett, D.E.; Heath, D.C.

1982-10-01

One part of the safety analysis of offsite hazards for a nuclear power plant is consideration of accidents which could release toxic gases or vapors and thus jeopardize plant safety through incapacitation of the control room operators. The purpose of this work is to provide generic, bounding estimates of the maximum allowable shipping frequencies for the transport of a chemical near the plant, such that the regulatory criteria for the protection of the operators are met. A probabilistic methodology was developed and then applied to the truck and rail transport of an example chemical, chlorine. The current regulatory criteria are discussed in detail. For this study, a maximum allowable probability of occurrence of operator incapacitation of 10 - 5 per year was used in the example calculation for each mode of transport. Comprehensive tables of conditional probabilities are presented. Maximum allowable ahipping frequencies are then derived. These frequencies could be used as part of a generic, bounding criterion for the screening of toxic hazards safety analyses. Unless a transport survey assures shipping frequencies within 8 km of the plant on the order of or lower than 4/week for rail or 35/week for truck, the contol room should be isolatable and the shipping frequency then determines the degree of isolation needed. The need for isolation implies the need for toxic chemical detection at the air intake.For a self-detection case in which the smell threshold is significantly lower than the incapacitation threshold and the control room is isolatable, the corresponding trequencies are 11/week for rail or 115/week for truck. Self-contained breathing equipment is assumed to be used after 5 minutes

Toxicity testing and chemical analyses of recycled fibre-based paper for food contact

DEFF Research Database (Denmark)

Binderup, Mona-Lise; Pedersen, Gitte Alsing; Vinggaard, Anne

2002-01-01

of different qualities as food-contact materials and to Perform a preliminary evaluation of their suitability from a safety point of view, and, second, to evaluate the use of different in vitro toxicity tests for screening of paper and board. Paper produced from three different categories of recycled fibres (B...... of the paper products were extracted with either 99% ethanol or water. Potential migrants in the extracts were identified and semiquantified by GC-1R-MS or GC-HRMS. In parallel to the chemical analyses, a battery of four different in vitro toxicity tests with different endpoints were applied to the same...... was less cytotoxic than the extracts prepared from paper made from recycled fibres, and extracts prepared from C was the most cytotoxic. None of the extracts showed mutagenic activity No conclusion about the oestrogenic activity could be made, because all extracts were cytotoxic to the test organism (yeast...

In Silico Prediction of Chemical Toxicity for Drug Design Using Machine Learning Methods and Structural Alerts

Science.gov (United States)

Yang, Hongbin; Sun, Lixia; Li, Weihua; Liu, Guixia; Tang, Yun

2018-02-01

For a drug, safety is always the most important issue, including a variety of toxicities and adverse drug effects, which should be evaluated in preclinical and clinical trial phases. This review article at first simply introduced the computational methods used in prediction of chemical toxicity for drug design, including machine learning methods and structural alerts. Machine learning methods have been widely applied in qualitative classification and quantitative regression studies, while structural alerts can be regarded as a complementary tool for lead optimization. The emphasis of this article was put on the recent progress of predictive models built for various toxicities. Available databases and web servers were also provided. Though the methods and models are very helpful for drug design, there are still some challenges and limitations to be improved for drug safety assessment in the future.

In Silico Prediction of Chemical Toxicity for Drug Design Using Machine Learning Methods and Structural Alerts

Directory of Open Access Journals (Sweden)

Hongbin Yang

2018-02-01

Full Text Available During drug development, safety is always the most important issue, including a variety of toxicities and adverse drug effects, which should be evaluated in preclinical and clinical trial phases. This review article at first simply introduced the computational methods used in prediction of chemical toxicity for drug design, including machine learning methods and structural alerts. Machine learning methods have been widely applied in qualitative classification and quantitative regression studies, while structural alerts can be regarded as a complementary tool for lead optimization. The emphasis of this article was put on the recent progress of predictive models built for various toxicities. Available databases and web servers were also provided. Though the methods and models are very helpful for drug design, there are still some challenges and limitations to be improved for drug safety assessment in the future.

In Silico Prediction of Chemical Toxicity for Drug Design Using Machine Learning Methods and Structural Alerts.

Science.gov (United States)

Yang, Hongbin; Sun, Lixia; Li, Weihua; Liu, Guixia; Tang, Yun

2018-01-01

During drug development, safety is always the most important issue, including a variety of toxicities and adverse drug effects, which should be evaluated in preclinical and clinical trial phases. This review article at first simply introduced the computational methods used in prediction of chemical toxicity for drug design, including machine learning methods and structural alerts. Machine learning methods have been widely applied in qualitative classification and quantitative regression studies, while structural alerts can be regarded as a complementary tool for lead optimization. The emphasis of this article was put on the recent progress of predictive models built for various toxicities. Available databases and web servers were also provided. Though the methods and models are very helpful for drug design, there are still some challenges and limitations to be improved for drug safety assessment in the future.

A new index to assess chemicals increasing the greenhouse effect based on their toxicity to algae.

Science.gov (United States)

Wang, Ting; Zhang, Xiaoxian; Tian, Dayong; Gao, Ya; Lin, Zhifen; Liu, Ying; Kong, Lingyun

2015-11-01

CO2, as the typical greenhouse gas causing the greenhouse effect, is a major global environmental problem and has attracted increasing attention from governments. Using algae to eliminate CO2, which has been proposed as an effective way to reduce the greenhouse effect in the past decades, can be disturbed by a growing number of artificial chemicals. Thus, seven types of chemicals and Selenastrum capricornutum (algae) were examined in this study, and the good consistency between the toxicity of artificial chemicals to algae and the disturbance of carbon fixation by the chemicals was revealed. This consistency showed that the disturbance of an increasing number of artificial chemicals to the carbon fixation of algae might be a "malware" worsening the global greenhouse effect. Therefore, this study proposes an original, promising index to assess the risk of deepening the greenhouse effect by artificial chemicals before they are produced and marketed. Copyright © 2015 Elsevier B.V. All rights reserved.

Toxicity alarm: Case history

International Nuclear Information System (INIS)

Hogan, D.; Retallack, J.

1993-01-01

In late fall 1991, the Novacor petrochemical plant near Joffre, Alberta experienced a toxicity alarm, the first since its startup 14 years ago. Fish exposed to a normal toxicity test were stressed within 2 h and showed 100% mortality after 24 h. A history of the events leading up to, during, and after the toxicity alarm is presented. The major effluent sources were three cooling water systems. Although these sources are well characterized, the event causes were not immediately clear. Initial toxic screening indicated that one was very toxic, another moderately toxic, and the third not toxic at all. All three systems utilized the same chemical treatment program to avoid fouling: stabilized phosphates with minor variants. The most toxic of the cooling systems operated at 10-12 cycles, had three chemicals for biocide control, and had three makeup streams. Toxic and nontoxic system characteristics were compared. An in-depth modified toxicity identification and evaluation program was then performed to identify and evaluate the cause of the toxicity alarm for future prevention. The most probable causes of toxicity were identified by elimination. The combination of high numbers of cycles, hydrocarbons in the makeup water, and bromine added as an antifoulant resulted in formation of aromatic bromamines which are capable of causing the toxic condition experienced. 2 tabs

Behaviour of molten reactor fuels under accident conditions

International Nuclear Information System (INIS)

Xavier Swamikannu, A.; Mathews, C.K.

1980-01-01

The behaviour of molten reactor fuels under accident conditions has received considerable importance in recent times. The chemical processes that occur in the molten state among the fuel, the clad components and the concrete of the containment building under the conditions of a core melt down accident in oxide fuelled reactors have been reviewed with the purpose of identifying areas of developmental work required to be performed to assess and minimize the consequences of such an accident. This includes the computation and estimation of vapour pressure of various gaseous species over the fuel, the clad and the coolant, providing of sacrificial materials in the concrete in order to protect the containment building in order to prevent release of radioactive gases into the atmosphere and understanding the distribution and chemical state of fission products in the molten fuel in order to provide for the effective removal of their decay heats. (auth.)

Toxicity tests with crustaceans for detecting sublethal effects of potential endocrine disrupting chemicals

DEFF Research Database (Denmark)

Wollenberger, Leah

/antagonistic activity with the ecdysteroid-responsive Drosophila melanogaster BII cell line 6) to draft an OECD guideline proposal for testing of chemicals based on the experimental work performed within this study In preliminary investigations with A. tonsa were studied various parameters related to processes......New and updated test methods to detect and characterise endocrine disrupting chemicals are urgently needed for the purpose of environmental risk assessment. Although endocrine disruption in invertebrates has not been studied as extensive as in vertebrates, in particular in fish, numerous reports...... of the present Ph.D. project were: 1) to develop a fully synthetic saltwater medium suitable for laboratory culturing of marine copepods including their feeding organism as well as for toxicity testing 2) to identify sensitive endpoints related to growth, development and reproduction of the pelagic calanoid...

[Drugs and occupational accident].

Science.gov (United States)

Bratzke, H; Albers, C

1996-02-01

In a case of a fatal occupational accident (construction worker, fall from roof, urine test positive for cocaine and THC, e.g. cannabis) the question arised to what extent those drug-related occupational accidents occur. In the literature only few cases, mainly dealing with cannabis influence, have been reported, however, a higher number is suspected. Cocaine and other stimulating drugs (amphetamine) are more often used to increase physical fitness. By direct or indirect interference with vigilance these compounds may provoke accidents. Due to the lack of a legal basis proving of the influence of drugs at the working place is still very limited, although highly sensitive chemical-toxicological assay procedures are available to detect even the chronic abuse (in hair). In the general conditions of accident insurances a compensation is excluded when alcohol is involved, but drugs are not mentioned. It is indeed difficult to establish a concentration limit for drugs like that existing for alcohol (1.1%). In each case the assay of the drug involved and exact knowledge of its specific effects is in an essential prerequisite to prove the causal relationship.

Assessing the toxic effects of ethylene glycol ethers using Quantitative Structure Toxicity Relationship models

International Nuclear Information System (INIS)

Ruiz, Patricia; Mumtaz, Moiz; Gombar, Vijay

2011-01-01

Experimental determination of toxicity profiles consumes a great deal of time, money, and other resources. Consequently, businesses, societies, and regulators strive for reliable alternatives such as Quantitative Structure Toxicity Relationship (QSTR) models to fill gaps in toxicity profiles of compounds of concern to human health. The use of glycol ethers and their health effects have recently attracted the attention of international organizations such as the World Health Organization (WHO). The board members of Concise International Chemical Assessment Documents (CICAD) recently identified inadequate testing as well as gaps in toxicity profiles of ethylene glycol mono-n-alkyl ethers (EGEs). The CICAD board requested the ATSDR Computational Toxicology and Methods Development Laboratory to conduct QSTR assessments of certain specific toxicity endpoints for these chemicals. In order to evaluate the potential health effects of EGEs, CICAD proposed a critical QSTR analysis of the mutagenicity, carcinogenicity, and developmental effects of EGEs and other selected chemicals. We report here results of the application of QSTRs to assess rodent carcinogenicity, mutagenicity, and developmental toxicity of four EGEs: 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, and 2-butoxyethanol and their metabolites. Neither mutagenicity nor carcinogenicity is indicated for the parent compounds, but these compounds are predicted to be developmental toxicants. The predicted toxicity effects were subjected to reverse QSTR (rQSTR) analysis to identify structural attributes that may be the main drivers of the developmental toxicity potential of these compounds.

Natech accidents at industrial facilities. The case of the Wenchuan earthquake

OpenAIRE

Krausmann , Elisabeth; Cruz , Ana Maria; Affeltranger , Bastien

2009-01-01

International audience; Natural disasters can trigger chemical accidents (so-called Natech accidents) with severe consequences on man or the environment. This work highlights the main characteristics of earthquake-triggered Natechs by describing our insights from a field trip to chemical facilities in the area affected by the 12 May, 2008, Wenchuan earthquake in China. Our preliminary results indicate that damage was most severe in older facilities with masonry and un- or poorly reinforced co...

Synergy effect in accident simulation

International Nuclear Information System (INIS)

Alba, C.; Carlin, F.; Chenion, J.; Gaussens, G.; Le Meur, M.; Petitjean, M.

1984-05-01

Accidental breaking of PWR coolant canalization would entail water vaporization into confinement enclosure. Equipments would be simultaneously subjected to temperature and pressure increase, chemical spray, and radiation action of reactor core products. Some equipments have to work after accident in order to stop reactor running and blow out water calories. Usually, in France, accident simulation tests are carried out sequentialy: irradiation followed by thermodynamical and chemical tests. Equipments working is essentially due to those polymer materials behaviour. Is the polymers behaviour the same when they are either subjected to sequential test, or an accident (simultaneous action of irradiation and thermodynamical and chemical sequence). In order to answer to this question, nine polymer materials were subjected to simultaneous and sequential test in CESAR cell. Experiments were carried out in CESAR device with thermodynamical chocks and a temperature and pressure decrease profil in presence or without irradiation. So, the test is either simultaneous or sequential. Mechanical properties change are determined for the following polymeric materials. Two polyamide-imide varnishes used in motors and coils; one epoxydic resin, glass fiber charged (electrical insulating); polyphenylene sulfide, glass fiber charged, the Ryton R4 (electrical insulating); three elastomeric materials: Hypalon, fire proof by bromine or by alumina EPDM (cables jacket); VAMAC which is a polyethylene methyl polymethacrylate copolymer; then a silicon thermoset material glass fiber charged (electrical insulating). After test, usually, mechanical and electrical properties change of polymer materials show sequential experiment is more severe than simultaneous test however, Hypalon does not follow this law. For this polymer simultaneous test appears more severe than sequential experiment [fr

Bioassay of Lake Onego bottom sediments toxicity based on their chemical composition and deepwater macrozoobenthos state

Directory of Open Access Journals (Sweden)

Kalinkina Nataliya Michailovna

2017-03-01

Full Text Available The bioassay of the toxicity of bottom sediments sampled in different areas of Lake Onega was carried out by crustaceans biotesting (Ceriodaphnia affinis Lillijeborg. It was shown that in the most areas of Lake Onega there are non-toxic bottom sediments. Toxic bottom sediments were found in Kondopogskaya Bay, intensively polluted with pulp-and-paper mill wastewaters. For the first time in the deep central part of Lake Onega the area was revealed where the toxic bottom sediments contain a high content of iron, manganese and other trace elements typical for the central areas of the lake. The mapping of the bottom of Lake Onega was accomplished, and three zones were identified based on the analysis of the data concerning the chemical composition of bottom sediments, bioassay toxicity data and the results of the deepwater macrozoobenthos assessment. For each zone the parameters of the main groups of benthos (Amphipoda, Oligochaeta, Chironomidae were defined. The first zone is located in the area of intensive anthropogenic influence (Kondopogskaya Bay, Petrozavodskaya Bay, Povenets Bay, Kizhi Skerries. The second zone is located mostly in the deep part of Petrozavodskaya Bay, where the most intensive development of amphipods is observed. The third area is identified for the first time: it is located in the central deep part of Lake Onega, where the communities of macrozoobenthos are limited by a natural toxic factor.

Fluorescence-based assay as a new screening tool for toxic chemicals

Science.gov (United States)

Moczko, Ewa; Mirkes, Evgeny M.; Cáceres, César; Gorban, Alexander N.; Piletsky, Sergey

2016-09-01

Our study involves development of fluorescent cell-based diagnostic assay as a new approach in high-throughput screening method. This highly sensitive optical assay operates similarly to e-noses and e-tongues which combine semi-specific sensors and multivariate data analysis for monitoring biochemical processes. The optical assay consists of a mixture of environmental-sensitive fluorescent dyes and human skin cells that generate fluorescence spectra patterns distinctive for particular physico-chemical and physiological conditions. Using chemometric techniques the optical signal is processed providing qualitative information about analytical characteristics of the samples. This integrated approach has been successfully applied (with sensitivity of 93% and specificity of 97%) in assessing whether particular chemical agents are irritating or not for human skin. It has several advantages compared with traditional biochemical or biological assays and can impact the new way of high-throughput screening and understanding cell activity. It also can provide reliable and reproducible method for assessing a risk of exposing people to different harmful substances, identification active compounds in toxicity screening and safety assessment of drugs, cosmetic or their specific ingredients.

Critical analysis of accident scenario and consequences modelling applied to light-water reactor power plants for accident categories beyond the design basis accident (DBA)

International Nuclear Information System (INIS)

Brofferio, C.; Cagnetti, P.; Ferrara, V.; Manilia, E.; Pietrangeli, G.; Sennis, C.

1985-01-01

A critical analysis and sensitivity study of the modelling of accident scenarios and environmental consequences are presented, for light-water reactor accident categories beyond the standard design-basis-accident category. The first chapter, on ''source term'' deals with the release of fission products from a damaged core inventory and their migration within the primary circuit and the reactor containment. Particular attention is given to the influence of engineering safeguards intervention and of the chemical forms of the released fission products. The second chapter deals with their release to the atmosphere, transport and wet or dry deposition, outlining relevant partial effects and confronting short-duration or prolonged releases. The third chapter presents a variability analysis, for environmental contamination levels, for two extreme hypothetical scenarios, evidencing the importance of plume rise. A numerical plume rise model is outlined

Improving ecological risk assessment of persistent, bioaccumulative, and toxic (PBT) chemicals by using an integrated modeling system - An example assessing chloroparaffins in riverine environments.

Science.gov (United States)

Chemical risk assessment (CRA) is primarily carried out at the screening level relying on empirical relationships between chemical properties and tested toxicity effects. Ultimately, risk to aquatic ecosystems is strongly dependent on actual exposure, which depends on chemical pr...

Implementation of Responsible Care in the chemical industry: Evidence from Greece

International Nuclear Information System (INIS)

Evangelinos, K.I.; Nikolaou, I.E.; Karagiannis, A.

2010-01-01

The chemical industry can be held accountable for numerous large-scale accidents which have led to the release of dangerous hazardous materials, pollutants and toxic chemicals into the environment, two well-known examples being the Union Carbide Bhopal disaster and the Three Mile Island tragedy). To ensure environmental protection and the Health and Safety (H and S) of communities, the chemical industry has voluntarily adopted integrated management programs such as the Responsible Care Program. The theoretical body of relevant literature attempts to explain the origin of the Responsible Care Program (RCP) through socio-political and economic theories. At the same time, the empirical research examines the ways in which various factors affect the choice of the chemical industry in their adoption of the RCP. This paper contributes to the debate by examining the challenges and barriers faced by the Greek chemical industry when adopting RCP, the environmental and H and S issues that prevail and finally, the extent of participation of stakeholders in the planning of RCP in the sector.

Integrative Chemical-Biological Read-Across Approach for Chemical Hazard Classification

Science.gov (United States)

Low, Yen; Sedykh, Alexander; Fourches, Denis; Golbraikh, Alexander; Whelan, Maurice; Rusyn, Ivan; Tropsha, Alexander

2013-01-01

Traditional read-across approaches typically rely on the chemical similarity principle to predict chemical toxicity; however, the accuracy of such predictions is often inadequate due to the underlying complex mechanisms of toxicity. Here we report on the development of a hazard classification and visualization method that draws upon both chemical structural similarity and comparisons of biological responses to chemicals measured in multiple short-term assays (”biological” similarity). The Chemical-Biological Read-Across (CBRA) approach infers each compound's toxicity from those of both chemical and biological analogs whose similarities are determined by the Tanimoto coefficient. Classification accuracy of CBRA was compared to that of classical RA and other methods using chemical descriptors alone, or in combination with biological data. Different types of adverse effects (hepatotoxicity, hepatocarcinogenicity, mutagenicity, and acute lethality) were classified using several biological data types (gene expression profiling and cytotoxicity screening). CBRA-based hazard classification exhibited consistently high external classification accuracy and applicability to diverse chemicals. Transparency of the CBRA approach is aided by the use of radial plots that show the relative contribution of analogous chemical and biological neighbors. Identification of both chemical and biological features that give rise to the high accuracy of CBRA-based toxicity prediction facilitates mechanistic interpretation of the models. PMID:23848138

Criticality accident alarm system

International Nuclear Information System (INIS)

Malenfant, R.E.

1991-01-01

The American National Standard ANSI/ANS-8.3-1986, Criticality Accident Alarm System provides guidance for the establishment and maintenance of an alarm system to initiate personnel evacuation in the event of inadvertent criticality. In addition to identifying the physical features of the components of the system, the characteristics of accidents of concern are carefully delineated. Unfortunately, this ANSI Standard has led to considerable confusion in interpretation, and there is evidence that the ''minimum accident of concern'' may not be appropriate. Furthermore, although intended as a guide, the provisions of the standard are being rigorously applied, sometimes with interpretations that are not consistent. Although the standard is clear in the use of absorbed dose in free air of 20 rad, at least one installation has interpreted the requirement to apply to dose in soft tissue. The standard is also clear in specifying the response to both neutrons and gamma rays. An assembly of uranyl fluoride enriched to 5% 235 U was operated to simulate a potential accident. The dose, delivered in a free run excursion 2 m from the surface of the vessel, was greater than 500 rad, without ever exceeding a rate of 20 rad/min, which is the set point for activating an alarm that meets the standard. The presence of an alarm system would not have prevented any of the five major accidents in chemical operations nor is it absolutely certain that the alarms were solely responsible for reducing personnel exposures following the accident. Nevertheless, criticality alarm systems are now the subject of great effort and expense. 13 refs

Modeling Aquatic Toxicity through Chromatographic Systems.

Science.gov (United States)

Fernández-Pumarega, Alejandro; Amézqueta, Susana; Farré, Sandra; Muñoz-Pascual, Laura; Abraham, Michael H; Fuguet, Elisabet; Rosés, Martí

2017-08-01

Environmental risk assessment requires information about the toxicity of the growing number of chemical products coming from different origins that can contaminate water and become toxicants to aquatic species or other living beings via the trophic chain. Direct toxicity measurements using sensitive aquatic species can be carried out but they may become expensive and ethically questionable. Literature refers to the use of chromatographic measurements that correlate to the toxic effect of a compound over a specific aquatic species as an alternative to get toxicity information. In this work, we have studied the similarity in the response of the toxicity to different species and we have selected eight representative aquatic species (including tadpoles, fish, water fleas, protozoan, and bacteria) with known nonspecific toxicity to chemical substances. Next, we have selected four chromatographic systems offering good perspectives for surrogation of the eight selected aquatic systems, and thus prediction of toxicity from the chromatographic measurement. Then toxicity has been correlated to the chromatographic retention factor. Satisfactory correlation results have been obtained to emulate toxicity in five of the selected aquatic species through some of the chromatographic systems. Other aquatic species with similar characteristics to these five representative ones could also be emulated by using the same chromatographic systems. The final aim of this study is to model chemical products toxicity to aquatic species by means of chromatographic systems to reduce in vivo testing.

Full-thickness human skin explants for testing the toxicity of topically applied chemicals

International Nuclear Information System (INIS)

Nakamura, M.; Rikimaru, T.; Yano, T.; Moore, K.G.; Pula, P.J.; Schofield, B.H.; Dannenberg, A.M. Jr.

1990-01-01

This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36 degrees C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components

Full-thickness human skin explants for testing the toxicity of topically applied chemicals

Energy Technology Data Exchange (ETDEWEB)

Nakamura, M.; Rikimaru, T.; Yano, T.; Moore, K.G.; Pula, P.J.; Schofield, B.H.; Dannenberg, A.M. Jr. (Johns Hopkins Univ., Baltimore, MD (USA))

1990-09-01

This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36{degrees}C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components.

Accidents - Chernobyl accident

International Nuclear Information System (INIS)

2004-01-01

This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

Enhanced toxic cloud knockdown spray system for decontamination applications

Science.gov (United States)

Betty, Rita G [Rio Rancho, NM; Tucker, Mark D [Albuquerque, NM; Brockmann, John E [Albuquerque, NM; Lucero, Daniel A [Albuquerque, NM; Levin, Bruce L [Tijeras, NM; Leonard, Jonathan [Albuquerque, NM

2011-09-06

Methods and systems for knockdown and neutralization of toxic clouds of aerosolized chemical or biological warfare (CBW) agents and toxic industrial chemicals using a non-toxic, non-corrosive aqueous decontamination formulation.

Oocyte toxicity: female germ-cell loss from radiation and chemical exposures

International Nuclear Information System (INIS)

Dobson, R.L.

1984-01-01

In some mammals, female germ cells are extraordinarily sensitive to killing by exposure to ionizing radiation, especially during development. Immature oocytes, which constitute the lifetime germ-cell pool of the female, have an LD 50 in juvenile mice of only 6 rad (compared with typical LD 50 s of 100-300 rad for most other cell types studied). Essentially, the entire germ-cell supply in female squirrel monkeys is destroyed prenatally by exposure of only 0.7 rad/day. Severe but lesser destruction has been found in other species. However, evidence suggests (though not ruled out for all developmental stages) that unusually high sensitivity probably does not occur in the human female. Germ cells can also be killed by certain chemicals, and similarities exist between chemical and radiation effects. More than 75 compounds have been quantitatively studied in mice, with determination of OTI values (OTI = oocyte toxicity index = mouse LD 50 /oocyte LD 50 ) to measure the degree of preferential oocyte killing. High sensitivity in mice does not mean necessarily high sensitivity in women. Of special interest is the recent discovery that the lethal target in the extremely sensitive mouse immature oocyte is probably the plasma membrane, not DNA. Since mouse data form the main basis from which human genetic hazard (for both radiation and chemicals) is estimated, this has important implications for the determination of genetic risk in women

Acute sensitivity of freshwater mollusks and commonly tested invertebrates to select chemicals with different toxic models of action

Science.gov (United States)

Previous studies indicate that freshwater mollusks are more sensitive than commonly tested organisms to some chemicals, such as copper and ammonia. Nevertheless, mollusks are generally under-represented in toxicity databases. Studies are needed to generate data with which to comp...

Removal of toxic chemicals from water with activated carbon

Science.gov (United States)

Dawson, V.K.; Marking, L.L.; Bills, T.D.

1976-01-01

Activated carbon was effective in removing fish toxicants and anesthetics from water solutions. Its capacity to adsorb 3-trifluoromethyl-4-nitrophenol (TFM), antimycin, NoxfishA? (5% rotenone), Dibrorms, juglone, MSa??222, and benzocaine ranged from 0.1 to 64 mg per gram of carbon. The adsorptive capacity (end point considered as a significant discharge) of activated carbon for removal of TFM was determined at column depths of 15, 30, and 60 cm; temperatures of 7, 12, 17, and 22 C; pH's of 6.5, 7.5, 8.5, and 9.5; and flow rates of 50, 78, 100, 200, and 940 ml/min. Adsorptive capacity increased when the contact time was increased by reducing the flow rate or increasing the column depth. The adsorptive capacity was not significantly influenced by temperature but was substantially higher at pH 6.5 than at the other pH's tested. A practical and efficient filter for purifying chemically treated water was developed.

Toxicity Estimation Software Tool (TEST)

Science.gov (United States)

The Toxicity Estimation Software Tool (TEST) was developed to allow users to easily estimate the toxicity of chemicals using Quantitative Structure Activity Relationships (QSARs) methodologies. QSARs are mathematical models used to predict measures of toxicity from the physical c...

Membrane alterations following toxic chemical insult. Research progress report No. 3 (Final), 15 July 1984-31 January 1988

Energy Technology Data Exchange (ETDEWEB)

Liss, A.

1988-03-10

A procaryotic cell system was developed that can be used to determine the toxic action of chemicals acting at the level of the eucaryotic or procaryotic cytoplasmic membrane. Cell wall-less microbes known as mycoplasmas were used. In this current study, two perfluorinated fatty acids (CB and C10) were found to inhibit the growth of the test mycoplasmas. Two apparent activities, cytotoxicity and cytolysis, were observed. At high concentrations (>10 mM), a detergent-like action was noted. At low concentrations (<10 mM), cell death was observed without detectable cell lysis. Altering the cell membrane (the presumed target of the toxic compounds) resulted in altered levels to toxicity. Similar results were obtained when human or murine B-cells were used as the target organism. The toxic action of the perfluorinated fatty acids apparently involves some interaction with the membrane of the cells being treated.

An endothermic chemical process facility coupled to a high temperature reactor. Part II: Transient simulation of accident scenarios within the chemical plant

International Nuclear Information System (INIS)

Brown, Nicholas R.; Revankar, Shripad T.

2012-01-01

Highlights: ► Seven quantitative transient case studies were analyzed in a coupled PBMR and thermochemical sulfur cycle based hydrogen plant. ► Positive power excursion in the nuclear reactor were found for helium-inlet overcoolings. ► In all cases studied the maximum fuel temperatures in the nuclear reactor were 200 K below the design basis limit. - Abstract: Hydrogen generation using a high temperature nuclear reactor as a thermal driving vector is a promising future option for energy carrier production. In this scheme, the heat from the nuclear reactor drives an endothermic water-splitting plant, via coupling, through an intermediate heat exchanger. Transient study of the operational or accident events within the coupled plant is largely absent from the literature. In this paper, seven quantitative transient case studies are analyzed. The case studies consist of: (1) feed flow failure from one section of the chemical plant to another with an accompanying parametric study of the temperature in an individual reaction chamber, (2) product flow failure (recycle) within the chemical plant, (3) rupture or explosion within the chemical plant, (4) nuclear reactor helium inlet overcooling due to a process holding tank failure, (5) helium inlet overcooling as an anticipated transient without emergency nuclear reactor shutdown, (6) total failure of the chemical plant, (7) control rod insertion in the nuclear reactor. Various parametric studies based on the magnitude of the events were also performed. The only chemical plant initiated events that caused a positive power excursion in the nuclear reactor were helium-inlet overcoolings due to process holding tank failures or reaction chamber ruptures. Even for a severe sustained overcooling, the calculated maximum fuel temperatures in the nuclear reactor were 200 K below the design basis limit. The qualitative basis for the case studies and the analysis models are summarized in part I of this paper.

Chemical toxicity and radioactivity of depleted uranium: The evidence from in vivo and in vitro studies.

Science.gov (United States)

Asic, Adna; Kurtovic-Kozaric, Amina; Besic, Larisa; Mehinovic, Lejla; Hasic, Azra; Kozaric, Mirza; Hukic, Mirsada; Marjanovic, Damir

2017-07-01

The main aim of this review is to summarize and discuss the current state of knowledge on chemical toxicity and radioactivity of depleted uranium (DU) and their effect on living systems and cell lines. This was done by presenting a summary of previous investigations conducted on different mammalian body systems and cell cultures in terms of potential changes caused by either chemical toxicity or radioactivity of DU. In addition, the authors aimed to point out the limitations of those studies and possible future directions. The majority of both in vitro and in vivo studies performed using animal models regarding possible effects caused by acute or chronic DU exposure has been reviewed. Furthermore, exposure time and dose, DU particle solubility, and uranium isotopes as factors affecting the extent of DU effects have been discussed. Special attention has been dedicated to chromosomal aberrations, DNA damage and DNA breaks, as well as micronuclei formation and epigenetic changes, as DU has recently been considered a possible causative factor of all these processes. Therefore, this approach might represent a novel area of study of DU-related irradiation effects on health. Since different studies offer contradictory results, the main aim of this review is to summarize and briefly discuss previously obtained results in order to identify the current opinion on DU toxicity and radioactivity effects in relation to exposure type and duration, as well as DU properties. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of accident sequences and source terms at waste treatment and storage facilities for waste generated by U.S. Department of Energy Waste Management Operations, Volume 1: Sections 1-9

International Nuclear Information System (INIS)

Mueller, C.; Nabelssi, B.; Roglans-Ribas, J.

1995-04-01

This report documents the methodology, computational framework, and results of facility accident analyses performed for the U.S. Department of Energy (DOE) Waste Management Programmatic Environmental Impact Statement (WM PEIS). The accident sequences potentially important to human health risk are specified, their frequencies are assessed, and the resultant radiological and chemical source terms are evaluated. A personal computer-based computational framework and database have been developed that provide these results as input to the WM PEIS for calculation of human health risk impacts. The methodology is in compliance with the most recent guidance from DOE. It considers the spectrum of accident sequences that could occur in activities covered by the WM PEIS and uses a graded approach emphasizing the risk-dominant scenarios to facilitate discrimination among the various WM PEIS alternatives. Although it allows reasonable estimates of the risk impacts associated with each alternative, the main goal of the accident analysis methodology is to allow reliable estimates of the relative risks among the alternatives. The WM PEIS addresses management of five waste streams in the DOE complex: low-level waste (LLW), hazardous waste (HW), high-level waste (HLW), low-level mixed waste (LLMW), and transuranic waste (TRUW). Currently projected waste generation rates, storage inventories, and treatment process throughputs have been calculated for each of the waste streams. This report summarizes the accident analyses and aggregates the key results for each of the waste streams. Source terms are estimated and results are presented for each of the major DOE sites and facilities by WM PEIS alternative for each waste stream. The appendices identify the potential atmospheric release of each toxic chemical or radionuclide for each accident scenario studied. They also provide discussion of specific accident analysis data and guidance used or consulted in this report

Chemical and radiological vulnerability assessment in urban areas

Directory of Open Access Journals (Sweden)

Stojanović Božidar

2006-01-01

Full Text Available Cities and towns are faced with various types of threat from the extraordinary events involving chemical and radiological materials as exemplified by major chemical accidents, radiological incidents, fires, explosions, traffic accidents, terrorist attacks, etc. On the other hand, many sensitive or vulnerable assets exist within cities, such as: settlements, infrastructures, hospitals, schools, churches, businesses, government, and others. Besides emergency planning, the land use planning also represents an important tool for prevention or reduction of damages on people and other assets due to unwanted events. This paper considers development of method for inclusion vulnerability assessment in land use planning with objective to assess and limit the consequences in cities of likely accidents involving hazardous materials. We made preliminary assessment of criticality and vulnerability of the assets within Belgrade city area in respect to chemical sites and transportation roads that can be exposed to chemical accidents, or terrorist attacks.

The Simplest Flowchart Stating the Mechanisms for Organic Xenobiotics-induced Toxicity: Can it Possibly be Accepted as a "Central Dogma" for Toxic Mechanisms?

Science.gov (United States)

Park, Yeong-Chul; Lee, Sundong; Cho, Myung-Haing

2014-09-01

Xenobiotics causing a variety of toxicity in biological systems could be classified as two types, inorganic and organic chemicals. It is estimated that the organic xenobiotics are responsible for approximately 80~90% of chemical-induced toxicity in human population. In the class for toxicology, we have encountered some difficulties in explaining the mechanisms of toxicity caused especially by organic chemicals. Here, a simple flowchart was introduced for explaining the mechanism of toxicity caused by organic xenobiotics, as the central dogma of molecular biology. This flowchart, referred to as a central dogma, was described based on a view of various aspects as follows: direct-acting chemicals vs. indirect-acting chemicals, cytochrome P450-dependent vs. cytochrome P450-independent biotransformation, reactive intermediates, reactivation, toxicokinetics vs. toxicodynamics, and reversibility vs. irreversibility. Thus, the primary objective of this flowchart is to help better understanding of the organic xenobiotics-induced toxic mechanisms, providing a major pathway for toxicity occurring in biological systems.

Predicting algal growth inhibition toxicity: three-step strategy using structural and physicochemical properties.

Science.gov (United States)

Furuhama, A; Hasunuma, K; Hayashi, T I; Tatarazako, N

2016-05-01

We propose a three-step strategy that uses structural and physicochemical properties of chemicals to predict their 72 h algal growth inhibition toxicities against Pseudokirchneriella subcapitata. In Step 1, using a log D-based criterion and structural alerts, we produced an interspecies QSAR between algal and acute daphnid toxicities for initial screening of chemicals. In Step 2, we categorized chemicals according to the Verhaar scheme for aquatic toxicity, and we developed QSARs for toxicities of Class 1 (non-polar narcotic) and Class 2 (polar narcotic) chemicals by means of simple regression with a hydrophobicity descriptor and multiple regression with a hydrophobicity descriptor and a quantum chemical descriptor. Using the algal toxicities of the Class 1 chemicals, we proposed a baseline QSAR for calculating their excess toxicities. In Step 3, we used structural profiles to predict toxicity either quantitatively or qualitatively and to assign chemicals to the following categories: Pesticide, Reactive, Toxic, Toxic low and Uncategorized. Although this three-step strategy cannot be used to estimate the algal toxicities of all chemicals, it is useful for chemicals within its domain. The strategy is also applicable as a component of Integrated Approaches to Testing and Assessment.

Toxic releases from power plants

International Nuclear Information System (INIS)

Rubin, E.S.

1999-01-01

Beginning in 1998, electric power plants burning coal or oil must estimate and report their annual releases of toxic chemicals listed in the Toxics Release Inventory (TRI) published by the US Environmental Protection Agency (EPA). This paper identifies the toxic chemicals of greatest significance for the electric utility sector and develops quantitative estimates of the toxic releases reportable to the TRI for a representative coal-fired power plant. Key factors affecting the magnitude and types of toxic releases for individual power plants also are discussed. A national projection suggests that the magnitude of electric utility industry releases will surpass those of the manufacturing industries which current report to the TRI. Risk communication activities at the community level will be essential to interpret and provide context for the new TRI results

Waste Evaporator Accident Simulation Using RELAP5 Computer Code

International Nuclear Information System (INIS)

POLIZZI, L.M.

2004-01-01

An evaporator is used on liquid waste from processing facilities to reduce the volume of the waste through heating the waste and allowing some of the water to be separated from the waste through boiling. This separation process allows for more efficient processing and storage of liquid waste. Commonly, the liquid waste consists of an aqueous solution of chemicals that over time could induce corrosion, and in turn weaken the tubes in the steam tube bundle of the waste evaporator that are used to heat the waste. This chemically induced corrosion could escalate into a possible tube leakage and/or the severance of a tube(s) in the tube bundle. In this paper, analyses of a waste evaporator system for the processing of liquid waste containing corrosive chemicals are presented to assess the system response to this accident scenario. This accident scenario is evaluated since its consequences can propagate to a release of hazardous material to the outside environment. It is therefore important to ensure that the evaporator system component structural integrity is not compromised, i.e. the design pressure and temperature of the system is not exceeded during the accident transient. The computer code used for the accident simulation is RELAP5-MOD31. The accident scenario analyzed includes a double-ended guillotine break of a tube in the tube bundle of the evaporator. A mitigated scenario is presented to evaluate the excursion of the peak pressure and temperature in the various components of the evaporator system to assess whether the protective actions and controls available are adequate to ensure that the structural integrity of the evaporator system is maintained and that no atmospheric release occurs