29 March 2012
Antibiotic contamination of soils mapped across Europe
A new study
provides an approach for estimating the risk of antibiotic contamination
associated with different soils and different antimicrobial products. The researchers estimated
and mapped soil contamination risk across Europe and suggest that their methods could be
used to inform antibiotic resistance monitoring or policies designed to reduce contamination.
have found that releasing antibiotics into the environment contributes to the development of
antibiotic resistance. A major source of antibiotics entering the environment is through agricultural use, in the
prevention and treatment of livestock diseases. The drugs are transferred to soils when manure from the animals is
spread on farmland. Under Directive EC 92/18/EC, all drugs used in veterinary medicine are subject to
ecotoxicological assessment of their environmental risks, but after a product is marketed, there is no requirement to
monitor build up in the environment, or resistance.
The characteristics of different antibiotics and soils affect how the drugs accumulate in the environment. In
environmental risk assessment, the contamination risk associated with an antibiotic depends on its behaviour in the
environment, including how quickly it breaks down and how well it sticks to particles in the soil. Soil factors, such as
organic matter content, as well as the chemical nature of the drug itself, can influence this behaviour.
This study estimated the effects of different soil types and farming practices on soil contamination by antibiotics.
The results were mapped to reveal how the risk of contamination varies across Europe. Contamination risk was
estimated using a measure the researchers called ‘soil vulnerability’, focusing on 12 common antibiotics used in pig
and cattle feed. They calculated soil vulnerability based on livestock densities (determining the amount of antibiotic
released), soil and antibiotic type, and land use.
According to their assessment, Belgium, Ireland, the Netherlands, Switzerland, Denmark, Germany and the UK
face the highest risk of contamination, while Bulgaria, Greece and Sweden face a much lower risk. The antibiotic
enrofloxacin, which previous studies have found in soil fertilized with poultry and cattle manure, was associated
with the highest risk of soil contamination in this study of soils fertilized with cattle and pig manure. Tetracycline
antibiotics, tylosin and sulfodiazine were also high risk, while chlorpyridazine, florfenicol and sulfamethazine were
low risk. Tetracyclines are the most heavily used antibiotics in agriculture, and have been found previously in soils
fertilized with manure from pigs, cattle and poultry. But the high risks associated with tetracyclines and enrofloxacin
are also related to values describing their ability to stick to and remain in the soil – compared to some of the lower
risk antibiotics they stick tightly and take a long time to break down.
The researchers say their study, based purely on data analysis and mapping of vulnerability, provides a framework
for evaluating antibiotic contamination risk over large areas. Using grids with 10km-wide squares, they were also
able to illustrate risk at smaller scales, for instance, they could pinpoint contamination hotspots in the southwest of
England and the north-western tip of France.
Approaches that rank different regions and antimicrobial products according to contamination risk may be useful in
decision-making about antibiotic use and in prioritising monitoring of antibiotic resistance. However, in the current
study, estimates were produced without detailed national data, requiring assumptions and oversimplifications that
may leave the results open to some inaccuracy. It would be preferable to use data accurate to the level of individual
farms or even individual animals. Environmental risk data for antibiotics were also limited because companies are
not required to release such information publicly. The researchers say open access to this data would help improve
future contamination risk assessments. Source:
De La Torre, A. Iglesias, I., Carballo, M., Ramírez, P., Muñoz, M.J. (2012). An approach for mapping the vulnerability of European
Union Soils to Antibiotic Contamination. Science of the Total Environment
. 414: 672-679. ContacTheme(s): Agriculture, Soil
The contents and views included in Science for Environment Policy are based on independent, peer-reviewed research and do not necessarily reflect
the position of the European Commission.
To cite this article/service: "Science for Environment Policy": European Commission DG Environment News Alert Service, edited by
SCU, The University of the West of England, Bristol.
European Commission DG ENV
DISCHARGE INSTRUCTIONS AFTER ENDONASAL SURGERY *Although post-operative recovery is somewhat different for everyone, here are some helpful guidelines for ACTIVITY: Get plenty of rest. For the first week after surgery, avoid heavy lifting (over 5 lbs), bending over, excessive straining and blowing your nose. For the first two weeks after surgery, you should not drive or exercise, however,
When Will the U.S. Flinch at Cancer Drug Prices? not responded to other treatments, based pinned on the targeted therapies—those that aim directly at cancer cells or that cut off a tumor’s blood supply without Erbitux (cetuximab), Tarceva (erlotinib), Colon Cancer Leads the Way Still, the future will likely bring more priced at thousands of dollars per month therapies. Tarc