Environment risk evaluation

Risk evaluation of accidents serves a dual purpose. It estimates tlie probability tliat an accident will occur iuid also assesses tlic severity of the consequences of an accident. Consequences may include dmnage to tlie surrounding environment, financial loss, or injury to life. This cliapter is primarily concerned witli tlie metliods used to identify hazards and tlie causes and consequences of accidents. Issues dealing witli healtli risks have been explored in die previous chapter. Risk assessment of accidents provides an effective way to help ensure eidier diat a mishap does not occur or reduces die likelihood of an accident. The result of the risk assessment allows concerned parties to take precaudons to prevent an accident before it liappens. 

This is why we should all advocate the Chinese meaning of the word risk, which comprises two risk elements, namely hazard and chance. With the discursive approach, following the systems approach of Rittel [14] and his long time companion Frank West Churchman (see foreword in Ref [25]), we have a chance to work in the complex environment to evaluate risk and chance with professional methods. 

While participating in the European Union programme on risk assessment of existing chemicals, Euro Chlor (representing all major European chlorine producers), recognised the need to carry out a detailed risk evaluation on chemicals linked to the production of chlorine. In view of concerns about specific risks of organohalogen compounds to the marine environment as a sink for all watercourses, Euro Chlor focused on this environmental compartment, with emphasis on the North Sea. This sea area has been extensively studied and is controlled by the Oslo and Paris Convention for the Prevention of Marine Pollution (OSPARCOM). For a series of chemicals on lists of concern adopted by the North Sea Conference (1990), risk assessments are being carried out to demonstrate their variable environmental profiles. 

The risk evaluation involves comparing the predicted environmental concentrations (PECs) with the predicted no effect concentrations (PNECs) and is expressed as a hazard quotient for the aquatic environment (Table 3.1). This quotient will indicate the necessity for further refinement of the risk assessment or eventually for risk reduction. 

Recently, the Commission has completed the review of existing pesticides that were on the market before 1993. After detailed risk evaluation with respect to their effects on humans and on the environment, only about 250 compounds, out of some 1,000 active substances, have passed the harmonised EU safety assessment [4]. 

In our work with characterizing PAH in the work environment, we have felt that it is necessary to establish body doses through appropriate body fluid analysis for a better risk evaluation of occupational exposure. Analysis of metabolites and adducts between cellular macromolecules and -metabolites is in progress. 

Risk assessment starts with risk identification, a systematic use of available information to identify hazards (i.e., events or other conditions that have the potential to cause harm). Information can be from a variety of sources including stakeholders, historical data, information from the literature, and mathematical or scientific analyses. Risk analysis is then conducted to estimate the degree of risk associated with the identified hazards. This is estimated based on the likelihood of occurrence and resultant severity of harm. In some risk management tools, the ability to detect the hazard may also be considered. If the hazard is readily detectable, this may be considered a factor in the overall risk assessment. Risk evaluation determines if the risk is acceptable based on specified criteria. In a quality system environment, criteria would include impact on the overall performance of the quality system and the quality attributes of the finished product. The value of the risk assessment depends on how robust the data used in the assessment process is judged to be. The risk assessment process should take into account assumptions and reasonable sources of uncertainty. Risk assessment activities should be documented. 

As shown previously, ENMs are released from products during use. This knowledge, however, is not sufficient to allow an estimation of the possible environmental risks that these ENMs may pose. The risks of any compound to organisms in the environment is linked to their exposure concentration. Because of the lack of analytical measurements of ENMs in the environment, the expected concentrations in the environment have to be modeled. These modeled concentrations can then be used to evaluate the impact of an ENM or a certain ENM-containing product on the environment. This risk evaluation is needed to rate the impact of a certain ENMs and it also allows different ENM products and applications to be compared. 

Prerequisites are (1) a biological test system that is capable of registering the observed effect in an environmental system and (2) an applied concentration technique that acts as an interface between the environment and the test system. If biomonitoring indicates an unwanted exposure to chemicals, it must be translated in chemical terms. This chemical information can be used for control purposes to eliminate the exposure, preferably to a real no-effect level, so that no risk evaluation has to be made. This method requires a bioassay that is specific for an effect in an environmental system and a concentration technique that is specific for the collection and transition of compounds causing the effect. 

Complexity increases with an integral concept because more aspects must be taken into account. For a risk evaluation of chemicals in the environment, an integral concept is a prerequisite (see Figure 1). 

PCBs (polychlorinated biphenyls) A family of chemicals composed of biphenyl molecules that have been chlorinated to varying degrees, performance assessment A type of risk assessment in which the potential long-term impacts of hazardous waste disposal on human health and the environment are evaluated for the purpose of determining whether disposal of specific wastes at specific sites should be acceptable, persistence The length of time that a contaminant persists in the environment. 

Yuan, X.Y., Wang, Y., et al., 2003. Organochlorine residues of sediments in Taihu Lake and its risk evaluation. Environ. Sci. (Chinese) 24, 121-125. 

The potential for non-carcinogenic risk associated specifically with exposure to POPs contamination in the local marine environment was evaluated by calculating the HQ which was defined as the ratio of the LADD from consumption of locally-caught seafood (marine fish and shellfish) and incidental ingestion of marine water (during recreational activities) to the RfD (USEPA) or TDI (WHO) appropriately... 

More and more studies evaluating whether the HC5 values are protective for ecosystem structure and function are becoming available (Assumption 9 Emans et al. 1993 Solomon et al. 1996 Versteeg et al. 1999 Smit et al. 2002 Selck et al. 2002 van den Brink et al. 2002a Brock et al. 2004 Hose and Van den Brink 2004 Maltby et al. 2005). In general, all authors concluded that the SSD concept (in the form of an HC5) can provide a cost-effective risk evaluation to establish acceptable concentrations to set targets for pesticides in the aquatic environment (see Figure 4.5... 

Some technical problems. Implicit in the idea of a regulatory standard or criterion is some level of risk assessment and risk evaluation, more or less formally, and with more or less sophistication. By risk assessment I mean that some sort of calculation or estimate is made, however roughly, as to the likelihood of an adverse impact of a hazardous waste on human health or the environment. Then risk evaluation is some sort of calculation or estimate, however roughly, as to whether that likelihood or risk of adverse impact is acceptable, or not. 

In the stepwise process, the risk evaluation combines the results of the second step, hazard evaluation, with any information on actual exposure possibilities, including evaluating exposure sources, levels, frequencies, types and routes. The assessment effort involves interpreting the field verified data from the perspective of determining what the actual risk level to humans and the environment is in the real world circumstances posed by the activity being evaluated. 

Bernard, A., Broeckaert, F., De Poorter, G. et al. (2002). The Belgian PCB/dioxin incident analysis of the food chain contamination and health risk evaluation. Environ. Res. 88 1-18. 

The environmental agencies may be among the best suited for evaluating risk. Their expertise usually includes a sound knowledge of the particular features of the local environment, such as location of flood plains and water resources, and the liaairds of certain chemicals. They should be used to support tlie risk evaluating effort. The local or state environmental agencies are also a source for inventory of hazards on industrial sites. Tliis information will serve the committee. 

Most household cleaning products are formulated to be used with water and go down the drain into wastewater treatment systems (municipal sewage treatment plants or septic tank systems). To assure that these types of products are safe for the environment, manufacturers evaluate the impacts of product ingredients in wastewater treatment systems, streams, rivers, lakes, and estuaries. Environmental risk assessment considers the exposure concentrations and effects of individual ingredients. 

Many methods are available for analysis of petroleum hydrocarbon products, particularly in water and soil matrices. The current literature includes a number of studies that document the performance and limitations of the commonly used methods. Method modifications and new methods are being investigated to provide better information about the petroleum component content of environmental samples. However, the available analytical methodology alone may not provide adequate information for those who evaluate the movement of petroleum components in the environment or evaluate the health risks posed to humans (Heath et al. 1993a). 

V.F. Uricchio, R. Giordano, and N. Lopez, A Fuzzy Knowledge-based Decision Support System for Groundwater Pollution Risk Evaluation, J. Environ. Manag. 73(3), 189-197, Nov. (2004). 

The IPCS basic scientiHc risk evaluation documents are published in the Environmental Health Criteria Series (EHC). This series covers evaluation of specific chemicals or groups of chemicals and is designed for scientific experts responsible for the evaluation of the risk posed by chemicals to human health and the environment, enabling relevant authorities to establish policies for the safe use of these chemicals. 

Corrosion Testing Objectives of SCC testing are (i) determination of the risk of SCC for a given application and comparison of alloys (ii) examination of the effects of chemical composition, metallurgical processing, fabrication practices for structural components (iii) evaluation of protective systems and prediction of service life (iv) development of new alloys, which are less expensive, and offer a longer, safer, and efficient performance for chosen environments (v) evaluation of claims for SCC performance of improved mill products. 

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