CHENNAI: The untreated tannery effluents released by tanneries in Vellore district contaminate the groundwater and pose a major health risk such as cancer, kidney ailments, skin rashes and heart disruptions to people who consume it continuously, a new study has revealed
Researchers from Anna University have studied chromium and fluoride contamination in groundwater near leather tanning industries in and around Ambur in Vellore district to bring out the impact on human health.
"Groundwater in a majority of the locations in the study area were found to be unsuitable for drinking purpose owing to exceeding permissible limit of the major ions due to indiscriminate disposal of tannery effluent," researchers said in the study paper published in Chemosphere journal recently.
"Around 43 per cent of the sampling locations the groundwater was affected by tannery effluents. Isotope ratio of 53Cr/52Cr was high around the tannery units due to the disposal of tannery effluents in open channels," researchers pointed out.
Through saline water mixing (SWMI) they also confirmed the disposal of effluent without treatment.
There are totally 90 tanneries distributed at different places around Ambur town.
The tannery industries use several chemicals like sodium carbonate, sodium sulphate, chrome sulphate, fat liquors, vegetable oil and dyes for leather processing.
The research paper said around 40 per cent of samples are having a high concentration of chromium which is above the permissible limit.
"Around 37 per cent of the samples exceed hazard quotient (HQ) suggesting serious health effects on the people who consume the contaminated water continuously. Such scenario possibly induces serious health effects such as cancer of lungs and stomach, skin rashes, heart disruptions and damage of kidney," said Professor L.Elango from Anna University and one of the authors of the paper.
As of now, common effluent treatment plants located in Thuthipattu, Pernambur and it covers 49 tanneries totally. Around 18 individual effluent treatment plants located are covered by Thuthipattu (8) and Ambur (10).
But, the studies found out tanneries are still releasing untreated effluent in the open channels as the contamination was more near the tanneries.
"Lack of efficient treatment by the plants in the tannery industry force them to dispose of the generated effluents into the open drain and through infiltration, it affects the freshwater aquifer zone," professor Elango pointed out.
To improve the condition, researchers suggested various measures including the improvement in the performance of effluent treatment plants, supplying treated water for domestic use and plan for rainfall recharge structures.