By Syed Akbar
Hyderabad: Patancheru and its surrounding areas in Hyderabad
are well known for soil and water pollution, but what is shocking is
that the contamination level of poisonous arsenic has touched 50,000
parts per billion (ppb) in certain pockets. This is 1000 times more
than the maximum permissible level of 50 ppb for arsenic fixed by the
World Health Organisation.
Analysis of water and soil samples of Patancheru and nearby villages
collected by Environmental Information System (Envis) Centre in
Biogeochemistry, School of Environmental Sciences, Jawaharlal Nehru
University (JNU), Delhi, showed that arsenic levels ranged between 50
ppb and 50,000 ppb. Water flowing in the Peddavagu and Nakkavagu
drains that empty into the Manjira River has arsenic level of 5,000
ppb, 100 times more than the WHO limit. Manjira is one of the sources
of drinking water for people living in Hyderabad.
A separate study by the Indian Institute of Public Health, Hyderabad,
and Rollins School of Public Health, Emory University, Atlanta, USA,
revealed that arsenic in water consumed by residents of nearby
Bandlaguda may be associated with both non-cancer and cancer risks.
“Our results illustrate potential non-cancer and cancer risks
associated with ingestion of arsenic-contaminated water and thus the
urgent need for affordable, energy-efficient filtration options to
ensure safe drinking water for this and similar communities,” pointed
out researchers Raghupathy Anchala and Aneena S Pokkamthanam.
The JNU team drew up a geochemical map for Patancheru and Bolaram
areas. The map revealed arsenic pollution in surface as well as ground
water. The value of arsenic in stream water near the common effluent
treatment plant in Patancheru is as high as 40,000 ppb. At a few
locations, it touched 50,000 ppb.
Arsenic pollution spreads fast through the soil and ground water as it
forms complexes with organic acids. Such complex compounds help in the
fast migration of pollutants through the soil and aquifers, the JNU
team noted.
Ground water samples from Bandlaguda, Muthangi, Patelgudem and nearby
villages too are contaminated with wells showing 750 ppb of arsenic,
which is 15 times more than the WHO permissible limits. “Arsenic
present in Peddavagu migrates vertically and horizontally and
contaminates the ground water in the wells of adjoining villages which
is indicated by the high values of arsenic in well water,” the study
said.
The team also found that the effluent treatment plant does not clean
heavy metals, but concentrates more on parametres like chemical oxygen
demand, biological oxygen demand and total dissolved solids. “Once the
aquifer is contaminated, it is very difficult, if not impossible to
clean it. The well water in some of the villages is not suitable for
drinking or agriculture purpose due to high concentration of arsenic
and some other toxic metals,” the JNU team warned.
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