Human Food laced with Drug Residue
09 January 2013
Dr M.Sayedain Jaffery
Antibiotics, once known as wonder drugs ( may be, they still are ), are chemical, biochemical or biological derivatives that exert direct bactericidal effects and destroy the disease causing microorganism. However, unless used judiciously and as prescribed on the basis of their pharmaco-kinetic & pharmaco-dynamic peculiarities these sensitive products also have the potential to induce harmful after-effects and long term sequelae that are inimical to health. Self-medication or indiscriminate use of any drug, for that matter, is loaded with esoteric hazards like initiation of hypersensitivity, toxicity and uncalled for effects on microflora, pathogenic or not.
Due to empirical usage, mostly in incorrect doses or for inconsistent periods, resistance to almost all known antibiotics has widely emerged. In areas where such drugs are intensively & extensively used, the recalcitrant genes are progressively replacing the normal genesis of bacterial flora in animals as well in human beings. With the passage of time, the quantum of resistance developed in microorganisms also tends to aggravate. Population build-up of such drug-resistant microbes multiplies logarithmically and may contain variants that are capable to jump the species-barrier and establish an endless cyclic spread of infection, from animal-to-man-to-animal-to-man, and so on. Such zoonotic dissemination may eventually acquire pandemic proportions and various types of diseases may appear, that otherwise were curable through correct usage of a correct medicines, but start defying usual curative and preventive strategies.
Population of bacteria resistant to antibiotics can emerge due to :-
i) endogenous mutation or genetic re-assortment
ii) exogenous infection with a drug resistant strain,
iii) unnecessary and repeated exposures of the animal to drugs against
which the bacteria have acquired resistance,
iv) selective multiplication of drug resistant bacteria
Quite a wide range of antibiotics and chemo-therapeutic agents is extensively being used on animals, including those that constitute the bank of Human Food like Milk & Meat etc, of Goats, Sheep, Cattle and Buffaloes and, of course chicken Meat & the Egg. Unless completely utilised during metabolc process, a drug can, and does, leave some residue in the tissues & excretions of an animal undergoing drug therapy. This residue, howsoever negligible in amount, besides being capable to actuate hypersensitivity in the consumer of Food laced with un-utilised remnants of a drug, can also induce drug resistence in the organisms responsible for the disease. Later when subjected to treatment, by the same or other drug therapy, the patient fails to respond positively or may even exhibit abnormal reaction.
Transfer to man of the drug remnants, can either be direct through medication of the sick animal or contamination of Food chain, including water and environments where food is handled, like an Abattoir or Processing Plant, etc.
Resistance to antibiotics can also be transferred from one species of microorganisms to another, particularly those that are common pathogens. Survival of resistant strains opens avenues for unchecked procreation of “selected ones” that can contribute to uncontrolled multiplication of pathogens hard to destroy.
Since the mandatory withdrawal period recommended by manufacturers of antibiotics & other curative products is rarely, if ever, practiced, detectable levels of residue of antibacterial drugs present in the food chain, i.e. in Milk, Meat, Eggs and their products and also vegetables contaminated with drug resistant bacteria, are a source of scare for people involved in control or treatment of disease in animal and man.
Overall bacterial load is proportionate to the standard & efficacy of health & hygiene measures prevalent in animal and human environments, particularly in facilities concerned with food production. More effective is the hygiene, more invigorating will the food be; more bacterial count will end-up in more disease. If, through effective application of appropriate Bio-security and Quarantine, the level of disease is contained within limits, the need to use antibiotics and other drugs will also be curtailed. No doubt it is demanding but is not impossible to raise Food producing animals & birds that would ordinarily, not require medication. According to William Ossler, “the One out-standing feature that differentiates man from animals is the desire to take Medicines”
Self-medication is therefore the biggest curse of modern times and, the man exercises this choice on animals who otherwise are not fond of taking medicines.
In the wake of increasing attention being given to Food, which should not be contaminated with disease producing factors, there has also been noticeable awareness towards the hygienic standards obligatory for Food production operations from “start to finish” i.e., right from raising a Food producing animal to the final out-let for human consumption of Milk, Meat & Eggs produced. In order to be able to obtain disease-free Food, extra-ordinary attention has to be invested in such sensitive stages as rearing healthy flocks with particular reference to their nutrition, slaughter, dressing, packing, storage and transport etc Each & every stage, the product under processing has to go through before reaching the consumer, is loaded with potential hazards unless exclusive attention is focussed on hygiene. Hands of the workers and every item or piece of equipment or clothing, whatever for that matter that comes in contact with fresh and raw Flesh has to be sterile, i.e. free of all microbes, whether able to cause disease or not.
Mandatory codes of procedures, pertinent to the use of antibiotics & other potent drugs, are needed to provide guidelines to monitor & watch over each and every stage, through which a Food producing animal passes during critical periods of its rearing and growth. viz
a) status of Stress in environment (micro- as well as macrocosm)
b) standard of health of the flock and of the workers in pens/sheds
c) nutritive value of Feed, critically balanced to suit the need of animal/bird
d) type & volume of medicinal agents used in Feed and or Water, as an aid to promote growth or to check disease.
e) efficacy of physical barriers applied to protect the flock from extraneous factors inimical to health,
f) strategy of bio-Management enforced to help the animal develop resistance/immunity against infectious diseases
g) type & dosage of curative drugs & preventive vaccines used, duration of use and, period of their withdrawal before slaughter
h) quantum of the residue of Drugs used, in Milk, Meat, Eggs, etc
To achieve success in producing Food, free-of factors that may induce hyper-sensitivity against drugs or be inimical to health of the consumer, it is highly imperative that this important issue be discussed threadbare amongst professionally competent personnel responsible for Public and Animal Health Such a discussion will lead to formulating codes & guidelines aimed at educating general public, the producer as well the consumer to watch and establish quality criteria for Human Food derived from animals. Manufacturers of Antibiotics and other pharmaceutical products would also need to be associated with such a drug-residue evaluation programme.
In order to inculcate some sanity aimed at judicious application of bio-prophylactic and chemo-therapeutic measures to control and eradicate diseases in animals & birds, without sensitising the unwary consumer through transfer of drug residues in Foods obtained from animal origin, All the stake holders, (the Grower of animals/poultry; the Manufacturer & prescriber of antibiotics/ medicines/ Vaccines, the meat Processor; the Whole-sale intermediary; Retailer and of course the Consumer, who has the biggest stake, should join hands & heads to find out solution of this prevalent gross abuse of drugs.
Manufacturer of the chemo- and bio-products, in particular would not like to condone this indiscriminate use of their products, being prescribed by one not competent to do so. Manufacturers of chemo-, and bio-products would rather themselves like to enforce a system of monitoring the sale and use or abuse of their product in field. Injudicious and un-called for medication of animals/birds can to a great extent be controlled through education of the Farmer and application of strict self-monitoring by the trade & professional Association of Poultry producers, Diary Farmers, Pharmaceutical manufacturers, Wholesalers, Retailers, etc.
Unless some bold and effective move is made by such bodies and other interested individuals, the abuse of Highly hazardous and Potent drugs will continue unabated and the dangerous residues will continue to induce sensitisation in consumers, especially children. Involvement of Authorities responsible for regulating the Registration & Sales of Antibiotics and Drugs, be solicited, if necessary, after finding measures to overcome this abuse. by the stake holders in the public sector themselves.