Kolkata most polluted metro; India has highest PAH level: Study

PANAJI: Kolkata is the most polluted metropolis in the country with its pollution levels recorded highest among eight tropical Asian countries, according to study.

The study, on distribution and identification of source of persistent organic pollutants (POPs) was conducted in eight countries - Laos, Cambodia, Vietnam, Thailand, Philippines, Indonesia, Malaysia, India and Japan.

According to the study, India has highest PAHs (polycyclic aromatic hydrocarbons), a carcinogenic persistent organic pollutants (POPs) as compared to cities of other countries, the research paper published in Marine Pollution Bulletin, an international scientific journal, said.

Among major metropolis in India, Kolkata was found to be the most polluted city with its pollution levels recorded highest among the eight tropical Asian countries, the research paper added.

The research was undertaken by Indian scientist Dr Mahua Saha at Japan-based Tokyo University of Agriculture and Technology.

"In urban areas, the highest PAHs were found in India with an average of 11300 nano grams per gram and the lowest in Malaysia which was 206 nano grams per gram," it said.

According to the researcher, results were alarming for a country like India as its pollution levels were high compared to other tropical Asian countries.

POPs are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes.

"Public concern about contamination by POPs exists due to the multitude of evidence showing the negative effects of POPs on human health and the environment.

Several compounds have been identified as hormone disruptors which can alter normal function of endocrine and reproductive systems in humans and wildlife. Cardiovascular disease, cancer, obesity, and diabetes have also been linked to POPs," she said.