<P> Industrial wastewater treatment describes the processes used for treating wastewater that is produced by industries as an undesirable by - product . After treatment, the treated industrial wastewater (or effluent) may be reused or released to a sanitary sewer or to a surface water in the environment . </P> <P> Most industries produce some wastewater . Recent trends have been to minimise such production or to recycle treated wastewater within the production process . </P> <P> Battery manufacturers specialize in fabricating small devices for electronics and portable equipment (e.g., power tools), or larger, high - powered units for cars, trucks and other motorized vehicles . Pollutants generated at manufacturing plants includes cadmium, chromium, cobalt, copper, cyanide, iron, lead, manganese, mercury, nickel, oil & grease, silver and zinc . </P> <P> The specific pollutants discharged by organic chemical manufacturers vary widely from plant to plant, depending on the types of products manufactured, such as bulk organic chemicals, resins, pesticides, plastics, or synthetic fibers . Some of the organic compounds that may be discharged are benzene, chloroform, napthalene, phenols, toluene and vinyl chloride . Biochemical oxygen demand (BOD), which is a gross measurement of a range of organic pollutants, may be used to gauge the effectveness of a biological wastewater treatment system, and is used as a regulatory parameter in some discharge permits . Metal pollutant discharges may include chromium, copper, lead, nickel and zinc . </P>

Suggest a pollutant which can be found in the industrial effluent