Milk is the staple diet of the millions across India and around the world. The quality of milk in our country has never been as hotly debated as now. Although, India stands at top of the milk production table, milk availability per capita has been among the lowest in the world due to its huge population. This mismatch between the demand and the production has led to higher incidences of milk adulteration and contamination. To date, the milk quality has been defined by its nutritional value i.e., Fat% and Solids not fat (SNF %). But, with increasing awareness, the focus has now shifted to include the impact of milk quality on consumer’s health.

Depending on the animal health, animal management, and the milk production process, milk may contain a significant amount of undesirable biological substances including toxins, antibiotic residues, and somatic cells which need to be detected and their sources removed before the milk reaches the consumer table or it can be regarded as safe. As of now, none of these finds any mention on the milk packets that we borrow from the recognized dairies. FSSAI, the food quality regulator has also not come up with any stringent or binding requirements for declaring the saleable milk free of these contaminants. Although, the agency has defined the minimum permissible amount of these substances in milk, whether these are determined and any action taken before the milk is released for sale is still in question.

Sources of unsafe milk

Milk gets contaminated in several ways,thereby rendering it unsafe.Animal feed may contain several toxic substances which if not checked will come in milk. Most important of these are aflatoxins (AF). These are secondary metabolites of fungus, Aspergillus spp which are toxic as well as carcinogenic in nature. Most predominant aflatoxin in feed is AFB1 which gets converted to AFM1 in the animal’s body and secreted in milk.

Secondly, the presence of antibiotic residues in milk is a significant public health issue that has not been paid due attention. Owing to theeasy availability of antibiotics, they have been used indiscriminately in animals to counter various infections. These antibiotics and their residues find their way into the milk. Human exposure to these antibiotic residues for long periods will alter the beneficial microbiota resulting in digestive problems, and at the same time will aggravate the problem of antibiotic resistance.

Thirdly, the presence of bovine (cattle) somatic cells in milk has also never been deliberated before. In the western world, milk pricing is based on the numbers of somatic cells in milk. Although, there has been no evidence of a direct effect of bovine somatic cells on humans, higher than recommended somatic cells count of milk means the presence of infection and in turn antibiotic residues, if they have been used.

What needs to be done?

Safe and healthy milk is the choice of everyone. Quality controls need to be introduced at every step right from feed selection, feed screening, milk collection, storage and animal health management. Aflatoxins in feed are the result of the mold (fungus) growth. Improper storage of feed under excessive humidity and temperature favours development of aflatoxins. Proper selection, screening and storage of feed are of utmost importance to ensure least aflatoxin development. These toxins can be detected and removed or made inert before they are ingested by the animals. Several toxin binders are available in the market which can be added to the feed. These toxin binders conjugate with the aflatoxins making them unavailable for metabolism in the body leading to their excretion as such in the faeces. As per international standards, aflatoxins should be less than 20 ppb of animal feed.In milk, FSSAI recommends less than 0.5 ppb while European laws recommend less than 0.05 ppb of aflatoxins.

Secondly, the usage of antibiotics needs to be regulated as in case of humans. In cases where antibiotic use cannot be avoided, proper withdrawal time of the drug needs to be adhered to. Every drug takes certain time to be completely metabolised and removed from the body. Till that time, milk from that animal should either be discarded or put to non-human use. Several milk based antibiotic detection kits are available commercially. 

Somatic cells are normally present in milk and are primarily comprised of leukocytes and secretory cells. Increased somatic cell count (SCC) is due to neutrophils which are the result of intra-mammary infections, mostly bacterial. This problem becomes more significant in tropical areas where prevalence of intra-mammary infections in dairy herds is quite high. High SCC in milk can also be well correlated with poor farm and milk hygiene. United States has imposed strict limitations on SCC in milk and has even instituted it as national standard in defining milk quality. India too needs to have similar quality standards which will ensure both healthy animal as well as healthy milk.

FSSAI says milk is largely safe, is it so?

Recently, FSSAI conducted a National milk safety and quality survey (2018) where around 6500 samples were collected from all over the country and observed for the presence of contaminants and toxins. It stated that although the milk is largely safe, contamination due to AFM1 and antibiotic residues is a more serious problem rather than adulteration. Around 5.7% and 1.2% of samples were positive for AFM1 and antibiotic residues respectively, with concentrations beyond permissible limits. It is possible that many positive samples might have been regarded as safe owing to their below permissible levels of these contaminants. In this context, the conclusion of the report that milk is largely safe seems precarious. Most importantly, the report nowhere mentions whether individual antibiotics were tested or classes of antibiotics. Gentamycin and Amikacin, two of the most commonly used antibiotics in the dairy sector were left out as no upper residue limit in milk has been set for these. Also, it does not mention other veterinary drugs that are routinely used in dairy animals, and their impact on human health. A more exhaustive survey is the need of the hour that will throw light on the actual state of the milk quality in the country.

Conclusion

It seems that the message communicated to the public about milk safety was not accurate. This becomes particularly important in a society like ours where milk is a primaryfood, especially with children.  Further, this report suggests that unsafe milk is a pan India problem, and not restricted to a few states/ areas as concluded in the report.The apex food regulator needs to look into these issues. It has to update itself with discoveries and innovations in this field with customer interests in prime focus. Now the time has come to take every aspect of the milk quality into account before it reaches the consumer table. This will help the consumers to make an informed choice while procuring milk for consumption. The government also needs to take proactive action in this regard.