Pharmaceuticals

Laying-hens in a hen house Click to enlarge
Antibiotics are used on a large scale in industrialised farming.
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Pharmaceuticals, which have become a lynchpin of our high standard of living, improve our quality of life and palliate and cure human and veterinary diseases. However, pharmaceuticals need to be used sparingly and with due care, for their positive effects also entail human and environmental risks and collateral effects.

Introduction

Pharmaceuticals are used to treat, palliate and prevent disease. Antibiotics play a particularly important role in this regard in that they inhibit the growth and propagation of bacteria (bacteriostatic drugs) or kill bacteria (bactericides). But unfortunately, the extensive use of antibiotics for the treatment of infectious human and veterinary diseases entails more than just positive effects, in that the advent of resistant and multi-resistant bacterial strains constitute a major threat to both human and farm-animal health. The propagation and transfer of multi-resistance from farm animals to human pathogens is particularly hazardous, as such mechanisms provoke infections that are extremely difficult to treat.

In recent years, the active ingredients of pharmaceuticals, the effects thereof, and the environmental risks entailed by them have become an increasing focus of scientific research. In 2007 Sachverständigenrat für Umweltfragen (SRU; German Advisory Council on the Environment) recommended ways to reduce pharmaceutical drug use and assess the environmental risk entailed by these products. On this occasion, the panel also noted that no data concerning the amounts of pharmaceuticals being administered is available. The government’s 2008 Antibiotika-Resistenz -Strategie (DART) maps out a strategy for the reduction of antibiotic resistance propagation.

Veterinary drugs and the environment

Various antibiotics and anti-parasite drugs against infections from bacteria, single-cell animal organisms and parasites are used in the field of veterinary medicine. The UBA’s approval procedure for such drugs includes an environmental impact assessment, whereby drugs that pose an environmental risk may be subject to additional environmental health requirements. Although the use of antibiotics as growth promoters has been banned in the EU since 2006, massive amounts of such drugs are used as preventive and other therapies in the field of veterinary medicine. Anywhere from 60 to 80 per cent of the active ingredients of these drugs are excreted intact by the livestock, and can readily find their way into the environment via livestock manure or pasturing. Studies of fields fertilized using liquid manure containing antibiotics show that drug residues occur not only in the soil, but also in percolation water and in some cases groundwater. Rainfall can cause particles of fertilizer from farmland to be discharged into surface waterbodies. The environmental behaviour and effects of pharmaceutical residues are mainly determined by drug properties and their complex interactions with the environment. The extent to which inputs occur and the degree of risk entailed by such inputs remain unclear.

A UBA study is currently investigating the extent to which near-surface groundwater is polluted by various antibiotics, to which end 48 groundwater quality measurement stations in potentially polluted regions of Lower Saxony, North Rhine-Westphalia, Bavaria and Saxony were selected. The groundwater samples collected in the fall of 2012 and the spring of 2013 will be tested for residues of 24 veterinary drugs and their metabolites and transformation products. The study results will be released in the spring of 2014.

Amounts of veterinary drugs used for livestock farming

Official statistics concerning the administration of antibiotics by veterinarians, which were released for the first time in 2012, indicate that in 2011 some 1,734 tons of antibiotics were supplied to German veterinarians by pharmaceutical companies and wholesalers. Even allowing for the fact that not all of these drugs were actually administered, it is safe to assume that the amount of antibiotics involved here, particularly for intensive livestock farming, greatly exceeds the amount used in human medicine. Antibiotics use studies conducted in 2011 in North Rhine-Westphalia and Lower Saxony for poultry, pigs and cattle likewise showed that widespread use of antibiotics is more the rule than the exception.

These studies prompted the federal government to elaborate an antibiotics minimization framework involving the implementation of various measures aimed at documenting more accurately the use of antibiotics in the livestock farming sector, and implementing optimized data use procedures. In the interest of enacting such measures into law, the government drafted an amended version of the Pharmaceutical Drug Act (AMG), which, among other things, regulates the administration of veterinary drugs in Germany. Additionally, in 2000 the German Chamber of Veterinarians (Bundestierärztekammer) and a veterinary drug task force known as Arbeitsgruppe Tierarzneimittel der Länderarbeitsgemeinschaft Verbraucherschutz elaborated Leitlinien für den sorgfältigen Umgang mit antibakteriell wirksamen Tierarzneimitteln (Guidelines for careful use of veterinary antibiotics), which were updated in 2010. These recommendations provide veterinarians with a useful guide to the judicious use of antibiotics.

While the aforesaid antibiotics minimization concept is a first step toward curbing the use of antibiotics, the recommended measures are insufficient. In the UBA’s view, the concentration of veterinary drugs in groundwater should not exceed 0.1 µg/l, as is the case for pesticides and biocides.

Approaches in other countries

Sweden, Denmark, the Netherlands and other EU countries are aware of the hazards entailed by overuse and careless use of veterinary drugs for intensive livestock farming. The antibiotics reduction instruments that have been elaborated in these countries have already proved effective. In Sweden, for example, antibiotics use for livestock farming declined to 12 tons in 2011, according to a November 2011 report from Swedish infectious-disease control authorities.

In Denmark, antibiotics use was reduced by 30 per cent in 2011 relative to the prior year, thanks to the rollout of an oversight system, which apart from monitoring, involves a so called yellow card mechanism that regulates excessive administration of drugs. This system requires pig farmers to undertake prophylactic measures. As early as 1995, Denmark established an antibiotics minimization framework whose regulations were considerably tightened in 2012, in that the practice of administering prophylactic antibiotics to entire livestock herds was abolished in favour of a practice whereby only individual animals that fall ill may be given antibiotics.

Strict rules and measures aimed at antibiotics reduction are also on the books in the Netherlands, which after Germany and France is the third largest EU consumer of antibiotics (although data is not available from all member states). This prompted the Dutch government to tighten its minimization regulations in mid 2012 – to good effect, as it turns out, since according to University of Wageningen agro-economics department statistics, the policy goal of a 20 per cent reduction in livestock antibiotics use in 2011 relative to 2009 was exceeded. However, these results contradict the results of monitoring carried out by Dutch food safety authorities, which despite the multi-stage plan, found that antibiotics use was unduly high and thus tightened the regulations in this regard in 2012. The multi-stage plan sets various interim objectives that are vigilantly monitored by the government. The rules and measures that livestock farmers and veterinarians are bound by aim for self-regulation. This takes the form, for example, of livestock farmers whose antibiotics use is unduly high reporting this fact on the website of Dutch food safety authorities and being subject to serious financial penalties, or even being shut down. Moreover, such farmers and their vets are required to jointly develop a livestock health plan for their animals, adherence to which is monitored by the food safety authorities. Livestock farmers may only obtain veterinary drugs from their vets, and under the newly tightened rules (in 2012) such drugs may only be administered by a vet.