Manual on the biomarkers recommended for the MED POL Biomonitoring Programme

Abstract

The scope of this manual is to serve as an initial source of technical reference for laboratories interested to start routine biological-effects pollution monitoring. A number of biomarkers have been considered in this manual, starting from those capable of giving a general indication of biological stress due to pollution. These biomarkers of stress (general stress indices) include the assessment of damage to genetic and subcellular components. Both the elevation of enzymatic activity of the mixed function oxygenase system (MFO) and the induction of metallothionein (MT) protein synthesis also termed as biomarkers of exposure (specific stress indices), are considered.

The potential use of the last two biomarkers is considerable, since these biomarkers are able to show the cellular response to heavy metals (MT) and aromatic organic xenobiotic compounds (MFO), both of which are considered as being major pollutants in coastal areas. Such biomarkers seem to offer the best information on the biological response of the animals to the two classes of toxic pollutants therefore reporting an early warning signal that environmental damage is in progress. They have been carefully characterised in a number of marine organisms and proved to be suitable to identify a biological response induced by the effects of the chemical pollutants. However, due to the complex nature of these biological responses, extreme caution should be exercised when coming to interpret monitoring results from field stations. These responses have to be assessed in the light of the physiological status of the test organisms at the time of sampling which can be ascertained by the measurement of the two general stress indices mentioned above (genetic damage and alteration of lysosomal activity). This manual also attempts to address a number of technical pitfalls and whenever possible, suggests ways how to enhance the certainty of biomonitoring results.