DETERMINING biological oxygen demand (BOD), an important pollution indicator, from urban sewage wastes will now be easier and faster. Scientists at the Indian Institute of Chemical Technology in Hyderabad and the National Environmental Engineering Research Institute in Nagpur have developed a model that could be readily used to predict BOD once the chemical oxygen demand (COD) is known (Pollution Research, Vol 11, No 2).

Though BOD is useful in determining the extent of pollution from industrial and sewage wastes and is necessary to identify and design appropriate sewage disposal technology, its determination takes some five days. COD determination, on the other hand, takes just three hours.