Biomarkers behavioral effects

This third part of the book will be devoted mainly to the problem of addressing complex pollution problems and how they can be studied employing new biomarker assays that exploit new technologies of biomedical science. Chapter 13 will give a broad overview of this question. The following three chapters, The Ecotoxicological Effects of Herbicides, Endocrine Disrupters, and Neurotoxicity and Behavioral Effects, will all provide examples of the study of complex pollution problems. 

Because of their wide-ranging and holistic character, assays of behavioral effects have been used as screening procedures when testing for neurotoxicity (see, for example, Iversen 1991, Tilson 1993). They can provide sensitive indications of neurotoxic disturbances, which can then be traced back to their ultimate cause by using mechanistic biomarker assays. 

In a similar way, an integrated biomarker approach has a role when carrying out experiments in mesocosms. Under these controlled conditions, behavioral effects of neurotoxic pollutants, acting singly or in combination, can be monitored and compared with data on predator-prey relationships and effects at the population level. The employment of mechanistic biomarker assays can facilitate comparisons between results obtained in mesocosms and other data obtained in the field or in laboratory tests. Here is one way of attempting to answer the difficult question— how comparable are mesocosms to the real world ... 

Effect. Biomarkers of effects are not available for trichloroethylene. There is no clinical disease state that is unique to trichloroethylene exposure. Interpretation of the behavioral observations in humans is complicated by many factors, such as possible irritant effects of the odor and nonspecific effects on the nervous system (e.g., fatigue). Further studies in this area would be useful in determining the exposure levels that may be... 

Biomarker of effect. A measurable biochemical, physiologic, behavioral, or other alteration in an organism that, depending on the magnitude,... 

In general, standard tests for effects on survival, development, reproduction, and growth are used for EQS derivation. Other endpoints should be used if they are considered relevant at the population level (e.g., behavior and avoidance). It is currently not considered appropriate to use biomarker data (e.g., molecular and biochemical endpoints) for EQS derivation unless their relevance at the population level has been clearly demonstrated. 

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