Information needs sources, risk assessment

Safe use exceptions could apply to any use that does not result in significant contributions to environmental risks resulting from specific (i.e., point) sources. Equally, safe use exceptions to risk reduction decision-making would limit the number of consumer or professional uses subject to any given risk reduction strategy. This would apply to most industrial uses of the substances reviewed under the official EU risk assessment reports. The systems framework would therefore have avoided the need first for industry to report and then for regulators to review this information. The concept of permissible uses appears particularly relevant for the use of NP and NPE in spermicides and the use of penta-BDE in aircraft emergency evacuation systems [515]. 

The outcome of the risk assessment process must be recorded and appropriate safety information must be passed on to those at risk. For most practical classes, risk assessments will have been carried out in advance by the person in charge and the information necessary to minimize the risks to students may be given in the practical schedule. You will be asked to carry out risk assessments to familiarize yourself with the process and sources of information. Make sure you know how your department provides such information and that you have read the appropriate material before you begin your practical work. You should also pay close attention to the person in charge at the beginning of the practical session, as they may emphasize the major hazards and risks. In project work, you will need to be involved in the risk assessment process along with your supervisor, before you carry out any laboratory work. Any new materials synthesized during the project should be treated with the utmost respect. An example of a risk assessment is shown in Fig. 2.2. 

This book describes the state-of-the-art methods for synthesis and analysis of chlorinated paraffins. It provides an overview of their worldwide occurrence and impact and describes their toxicological properties. International regulations and production volumes are presented, as well as an example of a risk assessment study that was carried out in Japan. Therefore, this book will be useful not only for environmental scientists who need to study the occurrence and toxicology of chlorinated paraffins in environmental matrices, but also for authorities and producers who could use this book as a valuable and comprehensive source of information. 

Once a consistent approach for dealing with Safety Goals and Backfits is established, the NRC will have a means to consider backfits and safety issues in a systematic and consistent manner. The process for selecting backfit options will be clarified, and efforts can be focused on those issues most important to risk. While risk will not become the sole measure of the importance of an issue, it can be used to assure that issues are placed in their proper perspective. If a risk-based approach to backfitting is to be implemented, risk analyses must be available to the decision-makers, and the validity of those analyses clearly understood. In some cases, NRC-sponsored risk assessments and special studies can provide the needed information however, another source of information is becoming available. That information source is the Individual Plant Examinations (IPEs). 

For example, assume you want to estimate chemical exposure by a meadow vole, which serves as the food source for many predators. The goal of collecting this information is to set safe concentration levels in the soil to protect the predators. Using the human health approach, intake assumptions would be identified for the amount of food and soil consumed by the predators daily, and concentrations in food would be estimated from soil concentrations using models. If we assume that the predators are foxes, we would need to estimate chemical concentrations in meadow voles because this species is a staple in the diet of some foxes. This approach requires a substantial number of assumptions and nse of many models, each of which introduces uncertainty in the results. Alternatively, meadow voles could be collected and chemically analyzed to directly measnre chemical concentrations. These measured concentrations could then be used to estimate exposure by foxes, eliminating some of the uncertainty in the estimate. However, this involves sacrificing live animals in the wild, which is only done when necessary to meet the mutually identified goals of the risk assessment. 

Exposure Levels in Environmental Media. There is limited information available on the levels of fuel oils found in soil or water where fuel oils are used or stored. Most monitoring studies have been conducted in the aquatic environment following an accidental spill (EPA 1981 Teal et al. 1978). More data on levels of fuel oils or their components in the air, water, and soil around facilities where fuel oils are produced, stored, and used would be useful. Data on levels in contaminated surface water, groundwater, and soil are needed to assess the potential risk from these likely sources of exposure. 

Other research activities related to residential exposure assessment currently being sponsored by the USEPA include the National Human Exposure Assessment Survey (NHEXAS) (website http //www.epa.gov/heasd/edrb/nhexas.htm). In addition, the USEPA concluded a Co-operative Agreement, referred to as the Residential Exposure Assessment Project (REAP) with the Society for Risk Analysis (SRA) and the International Society of Exposure Analysis (ISEA) which resulted in a reference textbook (Baker et al, 2001) describing relevant methodologies, data sources and research needs for residential exposure assessment. The REAP and other efforts complement other USEPA initiatives, such as the development of the Series 875 guidelines, and will facilitate a sharing of information and other resources between the USEPA, other Federal and State agencies, industry, academia and other interested parties. 

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