Toxic heavy metal in Bengaluru's air, warn experts

Hen’s feather is the major carrier of heavy metals. Credit: Darshak Ithikkat

Eagle’s feather is found to have the least with four heavy metals. Credit: Darshak Ithikkat

Human feeding of poultry meat and pigeon meat has an indirect risk of their health. Credit: Darshak Ithikkat

Crow’s feather is a carrier of five heavy metals. Credit: Darshak Ithikkat

By Kapil Kajal

Activities like unplanned urbanisation, increasing fuel usage and toxic industrial emissions have raised the value of several air pollutants in the city. However, the city’s air also has heavy metal, which is harmful to health.

A study by the International Journal of Pure and Applied Research (IJPAR) detected heavy metals in the feathers of birds, the fur of animals and human hair in Bengaluru and among them, cadmium and iron are the most prevalent.

Trace elements such as chromium, copper, mercury, arsenic, cobalt, manganese, selenium, zinc and lead are considered to be heavy metals, and exposure leads to damaged or reduced function of the central nervous system and is able to induce toxicity even at a low level of exposure, the study added.

Dr T V Ramachandra, a professor with the Centre for Ecological Sciences at the Indian Institute of Sciences, stated that the garbage burning, traffic and industrial emissions in Bengaluru usually comprises metals, plastic and aerosols, and they emit out heavy metals like chromium, copper, mercury and lead in the air.

According to the IJPAR study, the hen’s feather is the major carrier of all seven heavy metals and eagle’s feather is found to have least with four heavy metals, whereas pigeon and crow’s feather with five heavy metals. Human feeding of poultry meat and pigeon meat has an indirect risk of their health and there may be a chance to get ingested into the body of humans and has a high-risk factor, it added.

Qualitative analysis of heavy metals in avian feathers, Source- IJPAR Study

Similarly, further investigation in the study for the fur of sheep, goat, cat and dog were considered and the result showed that molybdenum was identified only in the fur of sheep.

Qualitative analysis of heavy metals in the fur of animals, Source- IJPAR Study

Experimental studies were further carried out using the human male and female hair which showed the presence of common heavy metal such as iron, cadmium, magnesium, and sodium while mercury was identified only in human female hair whereas zinc was identified in male hair only.

Qualitative analysis of heavy metals in human hair, Source- IJPAR Study

According to a World Health Organization (WHO), the heavy metals cadmium, lead and mercury are common air pollutants, emitted mainly as a result of industrial activity. Even low atmospheric levels contribute to build-up in soils, where they persist in the environment and accumulate in the food chain both on land and in water and heavy metals are associated to different degrees with a wide range of conditions, including kidney and bone damage, developmental and neurobehavioral disorders, elevated blood pressure and potentially even lung cancer, the WHO study added.

Dr Shashidhara Gangaiah, a pulmonologist in Center for Science Spirituality, Bengaluru mentioned that heavy metals like lead, zinc, mercury, arsenic and chromium can damage the genetic growth of any individual especially kids and the industrial areas like Rajaji Nagar industrial area and Peenya industrial area, the hub of heavy metals in Bengaluru.

Dr Yellapa Reddy, the Governing Council Member of the Foundation for Ecological Security of India, mentioned that metals like mercury and lead can also affect plants, animals, water bodies and soil as well. He added that the industries should not be allowed in residential areas like Bengaluru.

(The author is Bengaluru - based freelance journalist and a member of 101Reporters.com, a pan-India network of grassroots reporters.)