Polycyclic aromatic hydrocarbon contamination in Pallikaranai wetland, Chennai, Tamil Nadu, India; Fish as an Indicator.

Abstract

Enormous quantities of man-made chemicals are being used every day to meet the ever increasing food, energy, transport and industrial demands. During the past few decades, there has only been a steady increase in the use of these chemicals leading to their excessive presence throughout the global environment. Wetlands, being the most fragile ecosystems have suffered the maximum. Extensive stretches of wetland habitats have been altered and destroyed. Among the gazillion types of chemicals, Persistent Organic Pollutants (POPs) are significant because they are resistant to degradation in the environment and biota. Due to their fat soluble nature and resistance to degradation, ingestion of certain POPs by fauna leads to bioaccumulation throughout their lives, generally in fat tissues, and biomagnification through food chain. Among the POPs, Polycyclic Aromatic Hydrocarbons (PAHs) are highly prevalent in vertebrates, particularly fishes. Polycyclic Aromatic Hydrocarbons (PAHs) are a unique class of POPs constituted by hundreds of individual organic compounds. These ubiquitous environmental contaminants are wide-spread in the air, bonded to particulate matter and readily bioavailable. Studies have demonstrated the carcinogenic, mutagenic and teratogenic behaviour of many of the PAHs. Based on their properties, 16 PAHs are listed as “priority pollutants” by the U.S. Environmental Protection Agency (EPA). These 16 PAHs are being measured and monitored in different environmental components in ecosystem throughout the globe.