Treatment of toxic effluents pumped out from dyeing units could become quite a cost-effective affair if the method evolved by a bio-tech research team from a Tiruchi college is put to use. The team has evolved a method to decolourise and de-odorise the effluents using bacteria isolated from the sludge deposits at the dyeing units themselves. “We isolated 24 bacteria from the solid waste dumped by textile units in Tiruppur and found that three of the bacteria could break the toxic compounds in the effluents, resulting in de-colourisation of the water,” said S .Senthil Kumar, lecturer at the Jamal Mohamed College.

Two bacteria in particular - Paenibacillus lautus and Bacillus firmus were able to purify the effluent up to 97% within 24 hours under laboratory conditions, said Senthil Kumar. The bacteria had survived over the years by consuming the chemicals in the sludge. When the bacteria were let into the effluent, they rapidly devoured the toxic compounds present. Subsequently, the team also conducted a test to check the purity of treated water. “We grew three samples of paddy, one each using pure water, effluent collected from the dyeing units and effluent treated with bacteria. Paddy irrigated with the treated water was as good as pure water. Almost 95% of the seeds germinated and grew,” says Senthil Kumar.

Even if the treated water could not be used for human consumption, it could atleast be used for agriculture, he said. The research findings were presented at ‘Biogeomon 2009’, an international biotechnology conference organized by Helsinki University in Finland recently. The team, comprising MS. Mohamed Jaabir, lecturer in Biotechnology and R. Ravikimar, Professor in the Department of Botany, also plans to conduct similar trials with the treated water on aquatic beings. Reverse osmosis is currently the recommended method to treat waste water let out from dyeing units. However, the high cost involved in the process has not enthused many of the dyeing units in Tiruppur, Erode and Karur to put up RO (Reverse Osmosis) plants to treat the large volumes of effluents they discharge into water bodies. “The contamination of surface water as well as ground water in these regions could be prevented if bacteria were used for purification. We are planning to approach textile units in Tiruppur for field experiments,” said Mohamed Jaabir.

Source:The Times of India, August 6, 2009.

The Mobile Culprit

You probably put it down any place that’s convenient, but consider this: Several studies on cell phones and personal digital assistants (PDAs) found that they carry tones of bacteria, including Staphylococus spp. (which can cause skin infections), Pseudomonas spp. (eye infections), and Salmonella spp. (stomach ailments). Many electronic devices are sheathed in leather or vinyl cases, which provide plenty of creases and crevices for germs to hide. So, use a disinfecting wipe a few times a week, and be conscious of where you rest personal items.

ENVIS CENTRE Newsletter Vol.7,Issue 3 July 2009