Contamination in milk/ Source of contamination in milk

Insecticide/Pesticide, Antibiotics, Industrial Chemical, Aflatoxins and Physical Contaminants by Dr.J.Roopavathy

1. Dr.J.Roopavathy Assistant Professor Department of Zoology Contaminants in Milk

2. When we talk about quality, It does not restrict ourselves to the bacteriological but also physical and chemical quality of raw milk before it reaches even the first chilling station As per the definition of adulteration the presence of residues of pesticides, heavy metals, antibiotics, aflatoxins , drugs, hormones, etc in excess quantities indicates adulteration As these residues are not inherent to milk so directed measures should be employed so that these residues can be eliminated and even if they are present, their level does not exceed the established standards Insecticide Pesticide Contaminant Antibiotics Industrial Chemicals Aflatoxins Physical Contaminant

3. Insecticide/Pesticides are the chemicals which are used to kill insects / pest to save the crop. When these chemicals are used irrationally could prove injurious to the health of the consumers Dairies should have infrastructure like gas liquid chromatographs having electron capture detector to detect organo – chlorine pesticides like DDT, aldrin , dialdrin , HCN, BHC, etc The standard laid down by the PFA for pesticide residues in milk and milk products should be adhered to This is only possible if we have the commitment and infrastructure to check the residue levels. Dairies are not adding or removing pesticides, the message has to flow to the farmers about the uses and their harmful effects if used in excess Insecticides / Pesticides

4. The use of certain pesticides have been prohibited because the residues of the chemicals may pass into the milk Likewise, certain sprays for crops which will later be eaten by milch animals have been prohibited or their use permitted only at certain periods of development because they may be recovered in the milk supply During 1960s it was reported that milk frequently contained pesticides, however, their levels were well below the safety limits However, some reports in India have indicated that the residues of the pesticides do sometimes exceed the permissible limit prescribed by PFA

5. Antibiotics In recent year, the dairy industry has come to use considerable quantities of antibiotics in the treatment of animal diseases, notably mastitis When such treatments are made, the milk from the treated animal is not supposed to be used for human consumption for at least 72 hours following the treatment If such milk is added to milk from untreated animals before the 72 hours period is completed, residual antibiotics may be detected in the entire supply These antibiotics may enter the milk or other dairy products has serious health implication and hence they must be used only as specified Penicillin apparently has greater influence on public health then other antibiotics in common use and thus has held the main interest in developing test procedures for residual antibiotics

6. Toxic industrial chemicals are a source of environmental contamination and also source of serious exposure to certain works places Heavy metals, for example, lead, mercury, cadmium, arsenic, etc have been reported in milk and milk products These environmental contaminants are harmful/toxic if they are ingested in higher concentration than what is prescribed by PFA act Lead and mercury are most frequently studied because they have been the cause of infant poisoning through milk. Lead is the single most common heavy metal pollutant of environment In general, urban dwellers are at greater risk than rural residents Higher values of lead in milk of urban population compared to rural ones, and higher values in colostrum compared to mature milk, have been reported At world level, concerns are being expressed for their harmful effects and their prescribed limits are being lowered frequently in order to ensure that the food available to the consumers is safe Industrial Chemical

7. Aflatoxins are fungal metabolities found as toxic contaminants of foods Aflatoxins are produced by the common moulds , Aspergillus flavus and A. parasiticus by virtue of their ability to produce aflatoxin These can be secreted in milk by the milch animal which has been fed with aflatoxin containing feeds Aflatoxins

8. Physical contaminant/hazards found in milk and milk products could be metal fragments, glass, wood splinters, stones, dirt, plastics, insects, etc The presence of these can cut the mouth, break teeth, cause choking or perforation in the alimentary tract If proper care is taken during production, transportation, processing and handling these physical contamination can be avoided Physical Contaminant

9. Reference Dairy Science Technology Vol. 1 Milk and Milk Processing ( Shivashraya Singh) https://www.google.com/url?sa=i&url=https%3a%2f%2fwww.slideshare.net%2fm-hameed%2fir-you-jhg-dr-m-younas-rana&psig=aovvaw0t3vqnlpelydhwkky7tgm2&ust=1605348062094000&source=images&cd=vfe&ved=0caiqjrxqfwotcjjq47ci_-wcfqaaaaadaaaaabad