Biomarkers of environmental pollutants

Thousands of pollutants enter daily into environment and exert various kinds of stress on organisms and ecosystems. Risk assessment of these pollutants to organisms and ecosystems is challenging because of diversities in chemical nature and mode of toxicity of the pollutants as well as variation in sensitivities of the organisms exposed to the pollutants. Even low, relatively innocuous concentrations of pollutants often produce deleterious effects on organisms, which are difficult to be predicted, because measurable effects are expressed only after prolonged exposure. But it may be too late to take remedial actions or steps to reduce risk when these incipient effects are expressed. Therefore, it is necessary to develop early warning signals or biomarkers that convincingly reflect adverse biological responses towards anthropogenic environmental toxins even at minute concentrations.