Developing methods to assess and predict the population level effects of environmental contaminants

Abstract

The field of ecological toxicity seems largely to have drifted away from what its title implies--assessing and predicting the ecological consequences of environmental contaminants--moving instead toward an emphasis on individual effects and physiologic case studies. This paper elucidates how a relatively new ecological methodology, interaction assessment (INTASS), could be useful in addressing the field's initial goals. Specifically, INTASS is a model platform and methodology, applicable across a broad array of taxa and habitat types, that can be used to construct population dynamics models from field data. Information on environmental contaminants and multiple stressors can be incorporated into these models in a form that bypasses the problems inherent in assessing uptake, chemical interactions in the environment, and synergistic effects in the organism. INTASS can, therefore, be used to evaluate the effects of contaminants and other stressors at the population level and to predict how changes in stressor levels or composition of contaminant mixtures, as well as various mitigation measures, might affect population dynamics.

Organic Pollutants in Coastal Waters, Sediments, and Biota: A Relevant Driver for Ecosystems During the Anthropocene?

“…The benefits of such testing approach may be important in terms of meeting regulatory needs, but it does not provide valuable information about the role that pollutants have at ecosystem level (Emlen and Springman 2009). In fact, the traditional toxicity tests have received notable criticism (see for example Hartung 2009).…”

Differential Phytosociological Interactions Involving Male and FemaleAtriplex bonnevillensis

“…For purposes of the INTASS analysis (for further details see Emlen and Springman 2007), an "individual" is generally considered to be the seed or, in the case of males, some other measure of reproductive contribution that can be expressed as a seed equivalent. For females, we estimated number of seeds by averaging the number of seeds counted on 3 randomly chosen inflorescences on the target plant and then multiplying this average by the number of inflorescences.…”

Ecological Risk Assessment and Natural Resource Damage Assessment: Synthesis of Assessment Procedures

“…For example, USDOI (2005b, 43 CFR §11.62[f][1][i]) defines injury occurring if a biological resource or its offspring have “undergone at least one of the following adverse changes in viability: death, disease, behavioral abnormalities, cancer, genetic mutations, physiological malfunctions (including malfunctions in reproduction), or physical deformations.” The regulations define fish neoplasm as an injury “when a statistically significant difference can be measured in the frequency of occurrence of the fish neoplasia when comparing population samples from the assessment area and a control area.” Other examples of suborganism endpoints in the USDOI NRDA regulations include measurements of eggshell thinning, cholinesterase enzyme inhibition, delta‐aminolevulinic acid dehydratase (ALAD) inhibition, and physical deformities (including external malformations, skeletal deformities, whole organ and soft tissue malformation, and histopathological lesions). Suborganism measures are not common in ERA, at least in part, because these sublethal measures have weaker causal links to organism processes of growth, survival and reproduction (Tannenbaum 2005; Emlen and Springman 2007).…”