Ecological risk assessment analysis

Studies may be designed for estimating exposures to a wide array of wildlife, including birds, mammals and amphibians. Many regulatory requirements involve birds, and less emphasis is currently placed on other species. As regulatory requirements evolve, ecological risk assessments will be required for more species. This may require alternative approaches for food item analysis to allow estimates of pesticide ingestion. 

A number of EIA theorists believe in incorporating formal RA methods into EIA as a way to cope with uncertainties, especially in impact prediction where a formal framework for ecological risk assessment (EcoRA) is already developed. It includes three generic phases problem formulation, analysis, and risk characterization followed by risk management. The analysis phase includes an exposure assessment and an ecological effects assessment (see, e.g., US EPA (1998)). 

Uncertainty analysis is increasingly used in ecological risk assessment and was the subject of an earlier Pellston workshop (Warren-Hicks and Moore 1998). The US Environmental Protection Agency (USEPA) has developed general principles for the use of Monte Carlo methods (USEPA 1997), which provide one of several approaches to incorporating variability and uncertainty in risk assessment. 

The Pellston workshop in February 2002, which produced this book, aimed to develop guidance and increased consensus on the use of uncertainty analysis methods in ecological risk assessment. The workshop focused on pesticides, and used case studies on pesticides, because of the urgent need created by the rapid move to using probabilistic methods in pesticide risk assessment. However, it was anticipated that the conclusions would also be highly relevant to other stressors, especially other contaminants. 

Norton SB. 1998. A ecological risk assessor s perspective of uncertainty. In Warren-Hicks WJ, Moore DRJ, editors. Uncertainty analysis in ecological risk assessment. Proceedings of the Pellston Workshop on Uncertainty Analysis in Ecological Risk Assessment, 23 to 28 August 1995. Pensacola (FL) SETAC. 

Another important reason for using multiple scenarios is to represent major sources of variability, or what-if scenarios to examine alternative assumptions about major uncertainties. This can be less unwieldy than including them in the model. Also, the distribution of outputs for each separate scenario will be narrower than when they are combined, which may aid interpretation and credibility. A special case of this occurs when it is desired to model the consequences of extreme or rare events or situations, for example, earthquakes. An example relevant to pesticides might be exposure of endangered species on migration. This use of multiple scenarios in ecological risk assessment has been termed scenario analysis, and is described in more detail in Ferenc and Foran (2000). 

Warren-Hicks WJ, Moore DJ, editors, 1998. Uncertainty analysis in ecological risk assessment Pensacola (EL) SETAC. 

There is some USEPA precedent for use of statistical meta-analysis in a regulatory context, including the recent meta-analysis of organophosphate-related acetylcholinesterase inhibition data and meta-analysis of epidemiological studies on effects of 2nd hand tobacco smoke exposure. Warren-Hicks and Moore (1998) provide some discussion of the potential applicability of meta-analysis to ecological risk assessments. 

The popularity of Monte Carlo for risk-based uncertainty analysis is somewhat driven by the fact that Monte Carlo is fundamentally easy to implement, particularly with the advent of the personal computer, and graphically based software like Crystal Ball (www.decisioneering.com) and Risk (www.palisade. com/risk.html). The availability of such software systems generally promotes the use of uncertainty analysis in ecological risk assessments, reducing the amount of mathematical and statistical knowledge required of the user to implement the... 

Practitioners of ecological risk assessments will frequently experience large uncertainty bounds on the estimates of risk. Unfortunately, characterizing and/or reducing uncertainty can be very costly. However, these costs must be balanced with the need to conduct sufficient analysis to make an informed decision. 

In the next chapter the studies were extended to perform an ecological risk assessment using all lines of evidence including chemical analysis, in vivo bioassays in the laboratory and in situ ecological biomarkers. 

The overall ecological risk assessment process is shown in Figure 28.1 and includes three primary phases (1) problem formulation, (2) analysis, and (3) risk characterization. Problem formulation includes the development of a conceptual model... 

The second phase of ecological risk assessment, the analysis phase, includes two principal activities characterization of exposure and characterization of ecological effects (Figure 28.1). 

Reinert KH, Giddings JM, Judd L. 2002. Effects analysis of time-varying or repeated exposures in aquatic ecological risk assessment of agrochemicals. Environ Toxicol Chem 21 1977-1992. 

Mokhtari A, Frey HC (2005) Recommended practice regarding selection of sensitivity analysis methods applied to microbial food safety process risk models. Human and Ecological Risk Assessment, 11(3) 591-605. 

Warren-Hicks WJ, Butcher JB (1996) Monte Carlo analysis Classical and Bayesian applications. Human and Ecological Risk Assessment, 2(4) 643-649. 

Summarize the scientific and practical state of the art and give an analysis of similarities and dissimilarities for human and ecological risk assessments concerning mixtures and current approaches (Section 5.3). 

Analysis of effects A phase in an ecological risk assessment in which the relationship between exposure to contaminants and effects on endpoint entities and properties is estimated along with associated uncertainties. 

Burmaster DE and Anderson PD (1994) Principles of good practice for the use of Monte Carlo techniques in human health and ecological risk assessments. Risk Analysis 14 477-481. 

See also Delaney Clause Food, Drug, and Cosmetic Act, US Food Quality Protection Act, US Good Laboratory Practices (GLP) Levels of Effect In Toxicological Assessment Pesticides Pharmacokinetics/Toxicokinetics Risk Assessment, Ecological Risk Assessment, Human Health Risk Characterization Toxicity Testing, Alternatives Uncertainty Analysis. 

See also Risk Assessment, Ecological Risk Assessment, Human Health Risk Characterization Risk Communication Sensitivity Analysis Uncertainty Analysis. 

Discuss an assessment baseline and measurement endpoints as analysis of ecological risk assessment. 

As mentioned before, the ecological risk assessment is characterized by a problem formulation process, analysis containing characterizations of exposure and effects, and a risk characterization process. Several outlying boxes serve to emphasize the importance of discussions during the problem formulation process between the risk assessor and the risk manager, and the critical nature of the acquisition of new data, verification of the risk assessment, and monitoring. The next few sections detail each aspect of this framework. 

What two components have been incorporated into the analysis component in the new framework for ecological risk assessment (as opposed to their separation in traditional risk assessment) ... 

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