Priority Pollutants: Fate, effects and remedies of organic priority pollutants
INTRODUCTION
Before starting any research it is important to know about pollutants and their toxicity in
the present environmental condition. Priority pollutants are a set of chemical compounds
which are released into the atmosphere by human activity whose concentrations are much
higher than the natural concentrations and are released to the environment, water etc. The
United States Environmental Protection Agency (USEPA) published in the Federal
Register listed 129 compounds and these compounds are called as priority pollutants.
These toxic chemicals are categorized based on their chemical behavior and their potential
threat to the environment. Even though after the listing of the pollutants by the EPA there
were problems in sampling design of pollutants because of lot of expense and difficulty
involved in monitoring all possible pollutants which may accumulate and/or transfer in the
environment.
In this paper we discuss about the list of the pollutants based on their toxicity and their
properties and the threat to the environment and several remediation techniques in
reducing the concentration of these pollutants. Our first paper is about categorizing the
pollutants into different groups and ranking them based on the chemical behavior and
biological significance of pollutants in aquatic form whereas the second paper discusses
more about the origin and effects of the pollutants and their sub division in various
environment compartments and the third paper talks about biodegradation of these organic
pollutants by a certain methodology. But it is difficult and expensive to research about
each pollutant as it is time consuming and it occurs in various environment compartments
for example in the aquatic life in the form of suspended particles or dissolved pollutants
etc. The most important step in setting priorities of the pollutants is to find out in which
environment compartment the pollutant is most likely to be found or is a biggest threat
(sediment, water and biota).
POLLUTANTS
The list of 129 pollutants is divided into 5 categories. Pollutants in categories 1 and 2 are
more important as they are tenacious and may bioaccumulate or enter food chains.
Categories 3 and 4 are tenacious but non accumulative and are toxic when exposed
directly. Category 5 comprises of pollutants which are not persistent and consequently
remain toxic only over a short period of time or at a limited distance from the pollutant
source. According to the list there are 15 metals and inorganics, 20 pesticides, 7
