HYDERABAD: Fighting harmful chemicals in milk is now just an extended boil away .With most of the milk supplied in Hyderabad laced with harmful veterinary drugs and pesticides, researchers from the city-based Telangana Veterinary University have suggested that milk be boiled for a few more minutes. They found that boiling milk for five minutes more leads to breakdown of harmful chemicals, making it relatively safer.
The team comprising Sujatha Singh and Krishnaiah Nelapati from the Department of Veterinary Public Health and Epidemiology , College of Veterinary Science and PV Narsimha Rao of Telangana Veterinary University noticed that boiling milk for longer leads to degradation of harmful chemicals such as hexachlorocyclohexane (HCH) and its constituents. The finding was published in the recent issue of the scientific journal `Veterinary World’. HCH (lindane) is used in agriculture and makes its way into milk through the food chain. Pesticide content up to 4mg per litre has been found in milk and milk products. Besides HCH isomers, even DDT residues have been found in milk. The researchers warned that these chemicals continue to build up in human bodies and at a certain stage can cause severe health complications. And the best way to remove these harmful chemicals in milk is to boil it for a few minutes more.
Pasteurisation removes harmful bacteria while boiling at home removes pesticide content. The team found that natural raw milk, which contained 0.0460 parts per million (ppm) of alpha-HCH, became relatively safer after boiling as the chemical content came down to 0.0150 ppm. This, in other words, means a reduction in chemical by 45.65%. As far as removal of chemical compounds is concerned, boiling worked better than pasteurisation and sterilisation. In case of beta-HCH, raw milk contained 0.0634 ppm.This chemical degraded after boiling to 0.0398 ppm (reduction by 37.22%). The content of gamma-HCH came down after boiling from 0.0158 ppm in raw milk to 0.0115 ppm (reduction of 27.21%). The delta-HCH content in raw milk was 0.4732 ppm, which came down by 34.06% to 0.312 ppm. All the HCH isomers put together, the contamination in raw milk was 0.5984 ppm and it came down by 37.55% to 0.3737 ppm after extra boiling.
The researchers said that the HCH residues detected in milk samples in Hyderabad exceeded the maximum residue level limit of 0.001 ppm as recommended by the World Health Organisation (WHO) and the Food and Agricultural Organisation(FAO). As prolonged consumption of contaminated milk could lead to cancers and other diseases, boiling for a few extra minutes could provide a shield from chemical residues, the researchers said.