[Determination of maximum permissible concentrations of industrial toxicants using the integral biochemical index]

Effects of patented mixtures of substances, used as drilling fluids in petroleum industry, on the activity of enzymes (cathepsin D, EC 3.4.23.5; catalase, EC 1.11.1.6; and DNase, EC 3.1.4.6) and the content of analytes (malondialdehyde, fatty acids, free and collagen-associated hydroxyproline, bile acids, and total protein) in liver, gills, muscles, gonads, and bile have been studied under aquarium conditions in mature river flounder and one-year-old salmon for the purpose of determining maximum permissible concentrations. Measuring 25-30 independent biochemical parameters per organ is sufficient for establishing a direct relationship between the concentration of an industrial toxicant and the integral biochemical index, a new characteristic defined as the ratio of the number of biochemical parameters significantly deviating from control values to the total number of the parameters measured.