Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Risk factors of liquid manure

04.12.2006
Antibiotics in animal excrements contaminate the soil

High amounts of antibiotics still are sad reality in large-scale livestock farming. According to the Bundesverband für Tiergesundheit e.V. (Federal Association for Animal Health), in Germany alone about 784 tons were used in 2005. What is supposed to protect pig, cow and chicken against infections, can also become dangerous to man. Structurally nearly unchanged antibiotics excreted from the animals are spread via liquid manure to agricultural soils and can re-enter the food chain via a plant uptake as recent studies prove.

To be able to confront this danger, the research group “Veterinary Medicines in Soil” sponsored by the German Research Foundation (DFG) examines the basic mechanisms and consequences of the use of antibiotics in livestock farming. With the goal to improve the risk assessment, scientists from Berlin, Aachen, Jülich, Braunschweig, Osnabrück, Dortmund, Trier and Bonn want to find out how and to what extend the drugs get in the environment and to what changes and chemical reactions they are subjected to.

The first step for the team of scientists around Prof. Dr. Michael Spiteller, head of the Institute of Environmental Research at Universität Dortmund, is to track the way of the drugs from the animal via liquid manure fertilization into the soil and to get exact data concerning type and amount of the active substances in the different phases for the first time.

In a first test series an antibiotic from the group of sulfonamides which are commonly used in large-scale livestock farming was orally administered to pigs. The radioactively labeled substance put the scientists in the position to establish exactly how much of the antibiotic stays in the animal and how much is excreted, by examining the excrements. The results give cause for concern: only 10 percent of the active substance stays in the animal, the rest is released into the environment via the excrements of the pigs. A maximum of 50 percent of the administered substance remains unchanged, and still exhibits full antibiotic activity, and about 50 percent accrue as metabolites – some of which are still biological active.

In the second part of the research project the scientists concentrate on the question, what happens with the active substances when they get into the soil via fertilization. Spiteller and his coworkers Dr. Sebastian Zühlke and Dr. Marc Lamshöft pursue two approaches to get data as precise as possible about the processes on and beneath the ground.

In the university’s own testing area liquid manure is applied under realistic agricultural conditions, and processes are examined. As the identification of active substances in the complex soil mix is rather complicated, the scientists complete the outdoor test with test series in the laboratory. Here they can also use radioactively labeled antibiotic substances and exactly identify metabolites developing in the soil with the highest accuracy. Latest instrumental analysis like high resolution mass spectrometry is used to verify the substances even in the smallest quantities. As the Dortmund environmental researchers describe it, “like looking for a needle in a haystack”.

The Dortmund scientist team found out that after 30 days the major part of the substances was composed or solidly bounded. But: two up to five percent remain in the soil – unbound – and therefore potentially able to get into the groundwater or food via plants. The scientists suspect that this pool of substances bound in the soil is virtually continuously regenerating. In case of these “free” substances there is the additional danger that they chemically – and hence also their effects – change, due to various processes going on in the soil.

Right now the scientists can give no serious statements about the exact risks the substances in the soil might represent. But even smallest quantities of antibiotic substances can cause bacteria to develop resistances which can restrict the use of human antibiotics against pathogenic germs. “And the effects on the microorganisms in the soil which on their part influence the soil fertility or the nitrogen supply, for example, have still not been completely explored”, Michael Spiteller states. Still a lot of work for the research group, which is trying to establish a scientific basis for a comprehensive risk analysis of antibacterial veterinary drugs in the soil, in project groups throughout Germany.

Ole Luennemann | alfa
Further information:
http://www.uni-dortmund.de

More articles from Agricultural and Forestry Science:

nachricht New data unearths pesticide peril in beehives
21.04.2017 | Cornell University

nachricht New rice fights off drought
04.04.2017 | RIKEN

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>