Environmental exposure assessment

Brouwer, A. (1996). Biomarkers for exposure and effect assessment of dioxins and PCBs. In lEH Report on The use of Biomarkers in Environmental Exposure Assessment Institute Environmental Health, Leicester, U.K. 51-58. 

Daniels, S.L., Hoerger, F.D., and Moolenar, R.J. Environmental exposure assessment experience under the Toxic Substance Conttol Act, Environ. Toxicol. Chem., 4(1) 107-117, 1985. 

Golet EM, Xifra I, Siegrist H et al (2003) Environmental exposure assessment of fluoroquinolone antibacterial agents from sewage to soil. Environ Sci Technol 37 3243-3249... 

Table 8.1 Component groups for gasoline based on C- number and main chemical composition. Reprinted with permission from Foster KL, Mackay D, Parkerton TF, Webster E, Milford L (2005) Five-stage environmental exposure assessment strategy for mixture gasoline as a case study. Environ Sci Technol 39 2711-2718. Copyright 2005 American Chemical Society...

Many other OECD activities on hazard/risk assessment are undertaken within programs such as Existing Chemicals, New Chemicals, and Pesticides and Biocides, which deal with specific types of chemicals. The work on exposure assessment methods is undertaken by the Task Force on Environmental Exposure Assessment, consisting of experts. Most of the outcome of this work is published in the Series on Testing and Assessment or in Emission Scenario Documents, which are available at the OECD Web site (OECD 2006a). 

The OECD Task Force on Environmental Exposure Assessment is developing OECD-wide ESDs, in order to make it possible to reflect conditions on production, use, etc. that are different between countries, and to avoid duplicative efforts by Member countries and industry in gathering exposure information. The hrst process for developing OECD-wide ESDs is a submission of a project proposal from member countries. The proposal specifies the industry categories and/or use categories that the documents will cover. Once approved by the Task Force, the lead country drafts the document, and the draft will then be circulated to the member countries for their comments. Taking the comments into account, the drafts are amended and published by the OECD. 

OECD (1989) Compendium of environmental exposure assessment methods for chemicals. Paris, Organisation for Economic Co-operation and Development (Environmental Monograph No. 27). 

Ruckstuhl, S. (2001) Environmental Exposure Assessment of Sulfonated Naphthalene Formaldehyde Condensates and Sulfonated Naphthalenes Applied as Concrete Superplasticizers, Doctor of Natural Sciences Dissertation to Swiss Federal Institute of Technology, Zurich, Switzerland. 

Despite the wider availability of experimental data in these nations, risk assessments for new substances often demand estimation of environmentally important parameters. For example, degradation and partitioning processes must be considered in environmental exposure assessments, but neither Henry s Law constant nor abiotic degradation processes such as hydrolysis and photolysis are included in the MPD. Only if a substance is not readily biodegradable may requirements for abiotic degradation testing be imposed. 

In environmental exposure assessments, level II and III multimedia models require compart-mental half-lives (t1/2) for air, water, soil, and sediment. The most relevant compartments vary with the chemical being evaluated, but experimental data for every compartment are generally not available. To evaluate the environmental residence time of compounds adequately, the various degradation pathways have to be considered in combination. The extent, rates, and byproducts of the individual processes should preferably be integrated. The degradation reactions may take a... 

In human health risk assessment, direct and indirect methods of exposure assessment are distinguished. The direct method involves measurements of exposure at the point of contact or uptake, for instance, by monitoring chemical concentrations in humans or the environments they are exposed to (food, air, water). The indirect methods use modeling and extrapolation techniques to estimate exposure levels (Fryer et al. 2006). Also in environmental exposure assessment, these 2 ways to assess exposure may be applied. 

In general, calculations of industrial emissions rely on default values according to the industrial sector, emission rates, wind velocity and direction, anticipated substance flows through the environment, abatement technologies and wastewater treatment processes (see [114]). Site-specific assessments and local environmental exposure assessments must also account for geographic variability caused by climate, hydrology, geology, and biotic conditions [115]. 

R. L. Jones and G. Mangels, "Review Of The Validatim Of Models Used In Federal Insecticide, Fungicide, and Rodenticide Act Environmental Exposure Assessments , Env. Tox. Chem. 2002,21 (8), 1535-1544. 

Hagmar L, Welinder H, Linden K, AtteweU R, Osterman-Golkar S, Tornqvist M. An epidemiological study of cancer risk among workers exposed to ethylene oxide using hemoglobin adducts to validate environmental exposure assessments. Int Arch Occup Environ Health 1991 63(4) 271-7. 

Institute for Environmental Health (1996) The Use of Biomarkers in Environmental Exposure Assessment, Medical Research Council Report R5, ISBN 1-89911007-0. 

Monitoring data (measured data), together with calculated data (modelling estimation), are the basis for environmental exposure assessment through the calculation of a predicted environmental concentration (PEC). Compared to modelling data, measured... 

NICNAS (2004) Environmental exposure assessment of short chain chlorinated paraffins (SCCPs) in Australia July, 2004. A follow up report to the National Industrial Chemicals Notification and Assessment Scheme (NICNAS) Short Chain Chlorinated Paraffins (SCCPs) priority existing chemical assessment report No. 16. Australian Government, Department of Health and Ageing, National Industrial Chemicals Notification and Assessment Scheme (NICNAS) (cited by [2])... 

In previous publications. Ecological and Toxicological Association of Dyes and Organic Pigments Manufacturers (ETAD) has addressed the importance of workplace risk reduction by evaluating carefully human health hazard and occupational exposure [2-4]. This chapter addresses the environmental exposure assessment as a complementary information to data on ecotoxicological hazard profiles of colorants. 

The assessment of risk normally requires an evaluation of the intrinsic physico-chemical properties, i.e. biodegradability and toxicity, of the chemical. The risk assessment for surfactants is usually based on biodegradability and aquatic toxicity data. Generally in environmental exposure assessment, the concentration of a substance in the different environmental compartments is estimated from the amount of the substance released from domestic and industrial use. The PEC can therefore be calculated from a knowledge of the quantity of the substance that will be discharged (e.g. via waste-waters) into the environment and the distribution and degradation processes (e.g. waste-water treatment plant). 

OECD (1989a) Compendium of Environmental Exposure Assessment Methods for Chemicals, Environment Monograph No. 27, OECD, Paris. 

OECD (1993c) Report of the OECD Workshop on the Application of Simple Models for Environmental Exposure Assessment, Environment Monograph No. 69, OECD, Paris. 

Early environmental exposure assessments focused on releases to surface water under the premise that releases to terrestrial ecosystems or through landfills to the environment were negligible [48]. The US EPA utilized the... 

Environmental exposure assessments occur at different scales and in different media. Predicted environmental concentrations (PECs) may be developed for air, wafer, sediment, or soil, at local, regional, or continental scales. 

Environmental exposure assessment of biocides appears to be less systematically performed than does human exposure assessment. Some countries perform environmental exposure assessments for all use categories regulated, while others perform them on a case-by-case basis. All countries recognize the importance of use data in their assessment procedures, but they also recognize that collecting accurate information is difficult. Environmental monitoring data are not normally required, but are used when available. 

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