Question

Biochemical Oxygen Demand (BOD) may not be good index for pollution for water bodies receiving effluents from :

Answer 1

Domestic sewage, the most common source of pollution of water bodies, reduces dissolved oxygen but increases biochemical oxygen demand of receiving water. Higher BOD indicates more oxygen is required, which is less for oxygen-demanding species to feed on, and signifies lower water quality. Inversely, low BOD means less oxygen is being removed from water, so water is generally purer.

Biochemical Oxygen Demand (BOD) is not a good index for checking the pollution levels of water bodies receiving effluents from petroleum industry, this is because such effluents contain waste which are non-biodegradable.

Thus, BOD may not be good index for pollution for water bodies receiving effluents from "petroleum industry"