Metal levels much above limits in city lakes

A study on five lakes and the groundwater near those water bodies by a private college from the city has found that levels of heavy metals such as Hexavalent Chromium (CrVl), and lead are much higher than the 50 micrograms per litre as per the World Health Organisation (WHO) guidelines.

“Though research conducted on the water of Hussainsagar and other lakes only took the measurements of total Chromium levels, we only studied the levels of CrVl and lead, because they make water levels harmful for us,” explained Mala Das Sharma, head of the chemistry department at St. Pious X Degree and PG College for Women, Nacharam.

According to the results of her study, groundwater and lake samples from the Hussainsagar lake, Nacharam lake, Babanagar lake, Kapra lake and Safilguda lake showed that CrVl levels ranged from 57 to 268 micrograms per litre. The highest amount of CrVl, however, was found in the groundwater near Babanagar lake, which showed a reading of 268.3 micrograms per litre, while the water body itself had 118.3 micrograms per litre, much higher than WHO limit. Kapra lake water also is reportedly contaminated, showed the study.

Hussainsagar and Nacharam water bodies showed CrVl levels of 103 and 56.7 micrograms per litre. The CrVl level in the groundwater near the latter, however, was even higher at 86.7 micrograms per litre. In the Safilguda lake and the groundwater near it, the CrVl levels were found to be similar at 153.3 and 165 micrograms per litre

The study also showed a high presence of lead in those five lakes and the groundwater near them. “Though WHO says that only 10 micrograms per litre is the permissible limit, the Bureau of Indian Standards (BIS) has kept the level at 50 micrograms per litre,” said Dr. Sharma, while addressing students, delegates and the media at an awareness programme held in association with Save our Urban Lakes (SOUL).

City college conducts study on five lakes and groundwater near those water bodies