Heavy metals pollute Hyderabad and its suburbs

March 19, 2008
By Syed Akbar
Hyderabad, March 18: Rapid industrial and urban development in and around Hyderabad has taken a heavy toll of soils in neighbouring Ranga Reddy district with heavy metal contamination.
This is the first time that heavy metals have been found in considerable quantities in parts of Ranga Reddy district. A study by the city-based National Geophysical Research Institute revealed that soils in Ranga Reddy district are polluted by heavy metal, which are dangerous to the health of human beings and animals. Besides industrial growth, extensive use of agrochemicals in the last several decades has led to the accumulation of these metals in the surface soils, between 5 cm and 15 cm.
"These metals can infiltrate through the soil thereby causing ground water pollution," the study conducted by D Sujatha points out.
Heavy metals have a density of at least five times that of water and thus cannot be metabolised in the body. They go on accumulating in the body leading to major health problems. They affect mental functions, kidneys and lungs.
As part of the study, surface soil samples were obtained from south-eastern part of Ranga Reddy and analysed for the presence of 14 heavy metals like arsenic, barium, cobalt, chromium, copper, molybdenum, nickel, lead, rubidium, strontium, vanadium, yttrium, zinc and zirconium. The contamination of the soils was assessed on the basis of enrichment factor (ratio of metal), geoaccumulation index, contamination factor and degree of contamination.
The results reveal that variations in heavy element concentrations in the soil analysed have both geogenic (natural) and anthropogenic (human) contribution, due to the long period of constant human activities in the study area.
"The concentration of the metals like barium, rubidium, strontium, vanadium, yttrium and zirconium are interpreted to be mainly inherited from parent materials (rocks) and arsenic, cobalt, copper, chromium, molybdenum, nickel, lead and zinc concentrations show contribution from geogenic and anthropogenic sources. The major element variations in soils are determined by the composition of the parent material predominantly involving granites," the NGRI study said.