The head of the World Health Organisation has recently warned about antibiotic resistance caused by prodigal use of drugs on factory farms: “Greater quantities of antibiotics are used in healthy animals than in unhealthy humans.”
Animal-welfare societies have been campaigning for decades, having witnessed squalor, injury, suffering and death and evidence of heavy drug use inside factory farms. Though that is an extreme and possibly exaggerated view with which those within the industry would disagree, those drugs and others are, of course, necessary to keep an acceptable majority alive until slaughter, maximising growth rates and of profit also.
Though antibiotic and other drug use in the national herds and bird flocks are strictly regulated there is evidence of persistent drug residues in the food chain arising, almost inevitably, from over-use in the farming and livestock sectors.
The evidence is strong, and appears in the peer-reviewed medical, veterinary and scientific journals. But it is the comment by the head of WHO that “Greater quantities of antibiotics are used in healthy animals than in unhealthy humans” which catches the eye. Though the focus for these comments is the rapidly growing problem of antibiotic resistance, there is salience in observations of the wider problem of drug residues in the environment that has been a topic that we have previously visited on the Clinical Waste Discussion Forum.
It is not surprising that the presence of these and other drugs commonly found in natural water sources is so high. With human and veterinary use of so many drugs increasing steadily, in the latter being largely indiscriminate, concerns of pollution should not go unheeded. But how do these antibiotic and drug residues get into the environment? It is certainly not through the inappropriate disposal of a few tablets in a clinical waste sack, or of the residues present in an essentially empty drug vial or an empty syringe. Nor is it, we must hope, the drug traces present in the Sunday roast.
The excretion of drugs administered to both man and animals inevitably results in excretion of that drug, and its metabolites, usually in urine. Our urine output enters the sewage system and though some drug residues may decay rapidly others will pass through our Victorian wastewater treatment systems into the wider environment.
Animals are somewhat different. Urine goes directly to land, even for stock herds kept indoors. Solid wastes are spread on land as fertilizer, further distributing any drug residues that may be present.
Though the UK is ahead of the game with regard to administration of drugs to animals in order to protect the food chain it is inevitable that many drugs are administered, often indiscriminately and many for rather poor reasons. What we cannot control is the mainly urinary output of administered drug substances administered to man or animals.
Though there are some misguided attempts at control that seem to focus on the chastisement of patients who are warned not to ask for unnecessary repeat prescriptions, there is no parallel drive toward better prescribing. Nor is there any particular effort to improve sewage treatments, though work is in hand to introduce drug capture and elimination technologies to the wastewater outputs of some larger hospitals.
Sadly, the available scientific evidence is being misused. High drug concentrations in natural water, and the detection of high concentrations in hospital wastewater is taken as evidence of disposal errors by healthcare professionals and others. That rolls through to controls and constraints directed toward clinical waste management, similarly in the belief that there is some profound significance to the traces of drug that might be present in an empty syringe!
A broader overview of the problem would allow for rational development of suitable abatement technologies, appropriately cited and supported if necessary – and it probably is – by more aggressive control of drug use in the farming and agriculture sectors. Sadly, we see too much of the misdirected bullying that is predicated on an unfounded and unscientific view that clinical wastes are a significant source of drug contamination. Though there is every reason to address ALL sources and not just the greatest one or two, regulatory proselytising about drug residues in clinical wastes distinguishes those who propose such controls as wholly unscientific and degrades the regulatory process.