Types of pollutants and their effects on the environment

• BOD (Biochemical oxygen demand): the number of oxygen used by microbes to decompose organic matter present in waste. Aquatic fine day BOD 1-2ppm.

• COD (chemical oxygen demand): the number of oxygen is used to oxidize organic waste materials K2Cr2O7 dg. COD values ​​are always higher than BOD, because there is a material that is not oxidized by chemically oxidized biologically.

• TOC (total organic carbon), TOD (total oxygen demand): measure of the amount of organic substances by measuring the Number of CO2 after combustion.

• Thermal pollution: an increase in body temperature water causes a decrease in dropouts, increased activity of microorganisms and a shift in ecological equilibrium.

• Hazardous and toxic materials: such as heavy metals and chemicals (pesticides, cyanides, sulfides, etc.). Heavy metals Fe, Pb, Cu, Al, Cd, Hg, etc. resulting from the mud and certain chemical industries. Hg produced the mining industry and the burning of fossil fuels. Heavy metals and chemicals are toxic for living organisms. 5 ppm chromium poisoning the fish, from 0.1 to 0.5 ppm Cu poisoning bacteria and microorganisms.