Ecological risk assessment basics

Rutgers, M. (2000). Site-specific ecological risks a basic approach to the function-specific assessment of soil pollution, ISBN 9073270448, Wageningen, The Netherlands. 

The basic features of ecological risk assessment schemes are very similar throughout the world. Usually, one focuses on effects (concentration or dose response information), exposure, and risk characterization. The following paragraphs summarize how extrapolation practices can be developed in such a way that a consistent pattern emerges. 

Terrestrial ecological risk assessments are conducted following the standard framework and guidance published by the US EPA and various states. All but the most basic ecological risk assessments require a team of specialists to gather, analyze, and interpret information about fate and transport of pollutants... 

The previous sections of this chapter introduced some of the basics of ecological risk assessment. The first segment of this section presents an approach to making the estimates of ecological effects from laboratory data more realistic. The second section discusses an approach for estimating ecological risks to regions that have a variety of stressor and habitat types. 

This introductory section describes the purpose, scope, and intended audience for this report discusses the definition and application of ecological risk assessment outlines the basic elements of the proposed framework and describes the organization of this report. 

In addition, based on the discussions between the risk assessor and risk manager, follow-on activities to the risk assessment may be identified, including monitoring, studies to verify the predictions of the risk assessment, or the collection of additional data to reduce the uncertainties in the risk assessment. While a detailed discussion of the risk management process is beyond the scope of this report, consideration of the basic principles of ecological risk assessment described here will contribute to a final product that is both credible and germane to the needs of the risk manager. 

Rutgers, M., Faber, J., Postma, J. and Eijsackers, H. (2000) Site-specific Ecological Risks a Basic Approach to the Function-specific Assessment of Soil Pollution, vol. 28. Integrated Soil Research Programme, Wageningen. 

The primary focus of this study was to address the basic question - How consistent are the radionuchde concentrations in bee samples If one of the primary objectives is to eventually use data collected from honey bees as part of an environmental monitoring program, or more importantly, as input into an ecological risk assessment model, then one would hope there is a certain degree of consistency between samples. In other words, if 25 samples were collected from a beehive, and each one was analyzed for tritium, one would assume there would be relative consistency between the radiochemical analytical results. A large disparity in the concentrations of tritium in bee samples would make the results suspect. In this study, first the consistency of bee samples collected from a single colony was examined. Second, the consistency of samples collected from several colonies in the same location was assessed. 

EPA risk assessment framework and establish a common approach with its paradigm. The U.S. EPA s overall ecological risk assessment process is illustrated in Fig. 1. It consists of three basic elements Problem Formulation, Analysis, and Risk Characterization. 

Risk may arise from any chemicals released into the environment, intentionally or by accident, during manufacture, use or dissipation of the products. The expected concentration time profile for chemicals at specific locations in the various environmental media - water, air, soil and biota - may result in hazards to humans and the environment. Hence, ecological risk assessment must evaluate the probability whether the exposure level of potential contaminants may exceed effective (i.e. toxic) concentrations in the environmental compartment of concern. The basic principle is the comparison of the environmental and the toxic concentrations of the contaminants ... 

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