Concerned over the death of fish due to contamination in the Sirsa river in the Baddi area, the Himachal Pradesh Environment Protection and Pollution Control Board has laid down guidelines to control pollution. The death rate of fish has increased even after the installation of effluent treatment plants by industrial units. However, the board has found that pesticide units are the culprits. Highly poisonous chemicals used as raw material were washed into the river, killing a large number of fish.