Researchers in Calcutta and Dhaka have discovered yet another route by which arsenic reaches the human body: smoke from burning cow dung. Tens of thousands people in both West Bengal and Bangladesh who use cow dung cakes as fuel for cooking expose themselves to arsenic-laden smoke. The exposure is magnified because the kitchens are not ventilated. Women and children are the worst affected as they spend an average of seven hours next to the ovens daily. In unventilated conditions, women on an average would be exposed to more than 1,800 nanograms (ng) of arsenic, of which nearly 464 ng is absorbed by the respiratory tract, said a team of researchers led by Dipankar Chakraborti of Jadavpur University. The findings were reported in a recent issue of the Journal of Environmental Monitoring. Inhalation of arsenic leads to respiratory problems such as persistent cough and reduced lung capacity.

Dengue or chikungunya?

Researchers at the Rajiv Gandhi Institute of Biotechnology in Thiruvananthapuram have developed an easy-to-use diagnostic kit that can help doctors and technicians differentiate between chikungunya and dengue fever. Distinguishing one condition from the other is rather difficult as both the viral fevers are spread mainly by the Aedes aegypti mosquito and share several initial symptoms such as high fever and excruciating joint pain. The test uses polymerase chain reaction (PCR) methods that rapidly produce thousands of copies of a gene. It contains two sets of gene probes — one common to all the four types of dengue and another specific to chikungunya. More importantly, the new test identifies the disease in the second or third day of infection, while the conventional ones are able to detect the antibodies only after several days of the disease.