Occurrence of Organochlorine Pesticides Residues in Animal Feed and Fatty Bovine Tissue

Nowadays, more than 800 different kinds of pesticides are used for the control of insects, rodents, fungi and unwanted plants in the process of agricultural production. Although most of them leave the products or degrade in soil, water and atmosphere, some trace amounts of pesticide residues can be transferred to humans via the food chain, being poten‐ tially harmful to human health. [1] Pest control in intensive agriculture involves treatment of crops (fruits, vegetables, cereals, etc) pre and post harvest stages, rodenticides are em‐ ployed in the post-harvest storage stage, and fungicides are applied at any stage of the proc‐ ess depending on the crop. These chemicals can be transferred from plant to animal via the food chain. Furthermore, breeding animals and their accommodation can themselves be sprayed with pesticide solution to prevent pest infestations. Consequently, both these con‐ tamination routes can lead to bioaccumulation of persistent pesticides in food products of animal origin such as meat, fat, fish, eggs and milk. [2,3] During the last decades much at‐ tention has been given to this group of substances and the international level after it became apparent that they are transported through the environment and critical concentrations have been reached in some areas even in places where they have never been produced or used. Several countries banned the use of Organochlorine Pesticides (OCPs) during the 1970s and 1980s, although many of them continue to been used by other countries. OCPs have been identified as one of the major classes of environmental contaminants because of their persis‐ tence, long-range transport ability and human and animal toxic effects. OCPs are carcino‐ genic in animals as well as in human (International Agency for Research on Cancer, 1987). The immunotoxicity of selected OCPs has been also documented in vitro [4], in vivo [5], as well as in animals, in human fetal, neonatal and infant immune systems [6,7,8,9].