Friday, May 13, 2011

Bholakpur tragedy 2009: It was a deadly cocktail of poisonous heavy metals and dangerous coliform bacteria that led to cholera in Hyderabad

By Syed Akbar
Hyderabad, May 11: It was a deadly cocktail of poisonous heavy metals and dangerous coliform bacteria that was responsible for the Bholakpur tragedy involving 16 deaths and hospitalisation of over 500 people in May 2009.
Residents consumed water containing coliform bacteria 24,000 times in excess of the permissible limit. The heavy metal toxicity only added to the bacteriological problem, making it further deadly. Thus far, it has been believed that the deaths were only due to biological contamination. But chemical contamination too played its part.
While there's little improvement in the sanitation even two years after the tragedy, water samples collected by the city-based microbiology laboratory of the National Geophysical Research Institute (NGRI-CSIR) revealed the presence of poisonous heavy metals and dangerous coliform bacteria far beyond the permissible levels fixed by the World Health Organisation.
"There should be no coliform bacteria in potable water. But in samples collected from seven sub-localities of Bholakpur, the bacterial count exceeded 24,000 per litre. In one sub-locality, the count was 11,000 per litre," NGRI-CSIR senior scientist Dr AM Dayal told this correspondent.
The NGRI-CSIR study, conducted by Dr Mohammad Abdul Rasheed, Mutnuri Lakshmi and Patil J Dattatreya, has also found that the bacteria had adapted to the heavy metals. "Normally, bacteria die in the presence of heavy metals due to poisoning. But the presence of high quantity of heavy metals and exceptionally high number of coliform bacteria confirmed that the cholera and gastro-enteritis causing germs have learnt to survive heavy metal poisoning," Dr Rasheed and Lakshmi pointed out.
Heavy metal poisoning coupled with the presence of coliform bacteria further increased the toxic levels leading to the 16 deaths and severe health complications in hundreds of people. Incidentally, some of the toxicities caused by heavy metals and coliform bacteria are similar and this led to a synergetic effect on the health of the residents. The common symptoms are nausea, persistent vomiting, diarrhoea and abdominal pain.
"The drinking water samples were highly contaminated with high numbers of coliforms and in addition increased concentrations of iron, lead, copper, nickel, aluminium and sodium led to diarrhoeal outbreak in Bholakpur," Dr Dayal said, adding that pollution of water is increasing alarmingly creating serious threat to human health.
Samples were collected from municipal taps in Gulshan Nagar - I and II, Tazeer Nagar, Indira Nagar - I and II, Bangladesh market, and Mandigalli -I and II areas of Bholakpur in the city. The samples were compared with the water collected from the residential quarters of NGRI employees. While the Bholakpur samples failed both chemical and biological tests, there was no contamination in the NGRI water samples.

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