German-Dutch consortium presents project results

German-Dutch consortium presents project results
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The German-Dutch INTERREG project BEL AIR tested and developed solutions for clean and healthy air at poultry farms to prevent health risks from fine dust and endotoxin emissions. Eleven partners – companies and organisations from the German-Dutch border region – joined forces for this purpose and were guided through the four-year project by the lead partner GIQS e.V.

Emissions from animal houses are a much-discussed topic. Endotoxins, which are a particular challenge especially in poultry houses, are a special problem that is still underestimated in some cases. Improving emission levels in and around the barn can lead to a decrease in chronic lung diseases among residents and workers. Therefore, the project partners in BEL AIR spent four years investigating different methods that should lead to a reduction in particulate matter and endotoxin emissions. The focus was on products and technologies that combat endotoxins as close to the source as possible.

Sources of endotoxins

During the project it turned out that the detection of endotoxins is not always easy: Optimal sampling, sample preparation and sample evaluation depend on many factors. Influences of different parameters such as the ventilation system or the housing system in the barn play an important role and affect the endotoxin concentration as well as the sampling. And also the laboratory analysis at the end can be disturbed and falsified by chemical influences. Hygiene in the barn also has an influence on endotoxin contamination: endotoxins can also enter the barn from outside via contaminated water and feed, their supply lines or the air. Within the framework of BEL AIR, a lot of experience has been gained by the project partners with regard to the process of measurement, sampling, transport and sample processing.

Endotoxins in the barn come largely from feathers, dander, faeces and urine of the animals. Water, feed and bedding – according to an important result from the project – usually have only a minor influence. Endotoxin levels rise sharply in the course of the fattening cycle – when the animals get older and larger. Age, movement behaviour, plumage and length of stay have a very large influence on the release of endotoxins. Clear patterns have been identified here through the project activities.

Up to 70 percent reduction in endotoxins

Among the methods and technologies investigated in the project to reduce particulate matter and endotoxin emissions, some were found to be highly effective, while others failed to show any effects. For example, the use of an endotoxin-binding product, which is added to animal feed and acts in the animals’ intestines, did not lead to a demonstrable reduction in endotoxin emissions. A fogging spray, which was designed for regular barn cleaning and was supposed to bind fine dust to coarse dust, was also not able to demonstrably reduce the endotoxin load in the barn. And a specially prepared bacteriophage cocktail, which is administered to the animals in the first days of life in order to suppress the growth of germs in the animals’ bodies right from the start, could not be shown to reduce endotoxins either. The effect of a combined air scrubber, which combines a biological and a chemical process, was also studied, but no positive effect was found.

Various other methods, however, showed possibilities and opportunities that could lead to improvements in barn and ambient air quality. For example, there were encouraging results with ionisation technology. With the help of ionisation units, the barn air was treated in such a way that ultrafine dusts clump together and can then be removed more easily. However, after the end of the project, further measurements and further development will be required so that the coarse dust produced can ultimately be discharged to the outside in a controlled manner.

And the Vapur technology also delivered pleasing results: Here, the barn air is first treated by ultrasound waves and then with UV light. This leads to the clumping of ultra-fine dust in the first step and the killing of harmful bacteria and viruses in the second step. On the endotoxin concentration, these processes seem to have a positive effect, which has also been proven in laboratory tests. But here, too, further research is needed to optimise the technology for the needs in poultry houses.

A house management measure in which mucking out was done daily instead of every five days turned out to be very promising in the course of the project. Here, reduction values of more than 50 % for fine dust, more than 70 % for endotoxins and more than 80 % for ammonia could be measured. A similarly positive effect seems to have been achieved by the dry tunnel studied, where the animals’ excrement is regularly conveyed to the outside via manure belts and dried.

Further project successes

In addition to these results, the project has gained a lot of knowledge about different techniques and paved the way for developments that will lead to further improvements in air quality in and around poultry houses. Likewise, the partners were able to validate and establish a gentler, more sustainable and clearer analysis method for endotoxins with the rFC test in the project. And a new type of fine dust sensor was also developed in the BEL AIR consortium, with which the fine dust concentration in poultry houses can be measured around the clock for the first time.

A number of sensors installed, networked and connected to the internet in several test houses in the German-Dutch border area have also contributed to the findings. The results of the measurements and sampling are visualised in a BEL AIR dashboard developed in the project, in which it was possible to read directly via computer, tablet or smartphone for each test barn which climate and which air pollution currently prevails in the barn and how it is developing.

Statements of the project partners

At the end of the four joint project years, all partners involved could draw a positive balance. The joint German-Dutch project has resulted in many new findings on how to reduce endotoxin emissions in poultry houses and which measures are more likely to be unsuccessful. A lot of experience has also been gained in the measurement and analysis methods used: Marcel Steegh from the partner Whysor, for example, draws a positive conclusion: “We as a company are taking a lot away from the BEL AIR project. For example, how to measure fine dust and calibrate sensors, how to analyse endotoxins. But also that new sensors were developed, discovered and investigated, which also proved to be well applicable in practice.” And Angela van der Sanden from the Dutch project partner DLV Advies also draws a positive balance, even if no effect on endotoxin levels could be proven for some of the technologies and products investigated: “For this reason, it is important to carry out a project, as it involves risky investments. On the other hand, new insights into correlations and backgrounds have emerged that are valuable for the entire sector.”

For many partners, the (cross-border) exchange with the new international contacts was also very fruitful: “Due to the intensive, very enriching and trusting cooperation with the partners, there was a lively exchange and our staff learned a lot from other disciplines. We have learned a lot in dealing with the Dutch partners and have come to appreciate them very much,” says Rauni Kuczius from the Mikrobiologischen Labor Dr. Michael Lohmeyer. In times of Corona and avian influenza, however, it was not always easy for the project activities and also the (cross-border) cooperation: regular face-to-face meetings had to take place online due to Corona and also the barn trials were sometimes only possible to a limited extent or with more organisational effort due to lockdown and protective measures.

The BEL AIR project

Within the BEL AIR project, various technologies for the reduction of endotoxin emissions in and outside poultry houses have been (further) developed and tested by German and Dutch partners since the end of 2018. Endotoxins (lipopolysaccharides) are formed during the decay of Gram-negative bacteria and are also released in the gastrointestinal tract of animals and excreted with the faeces. They attach themselves to dust particles and can be partly responsible for respiratory diseases and restrictions of lung function in humans as well as animals. The project aimed to further reduce endotoxins and particulate matter, with the goal of contributing to a healthier living environment for people and animals in the barns as well as for local residents. For more information, see

BEL AIR was being implemented within the framework of the INTERREG V A programmes Deutschland-Nederland and was co-financed by the European Regional Development Fund (ERDF) and the Dutch Ministerie van Economische Zaken en Klimaat, the Ministry für Wirtschaft, Innovation, Klimaschutz und Energie des Landes Nordrhein-Westfalen and the provinces of Gelderland, Limburg and North Brabant. It is accompanied by the programme management at the Euregio Rhein-Waal.

With the lead partner GIQS e.V. a total of eleven partners from the German-Dutch border region were involved in the project: DLV Intensief Advies B.V., Jansen Poultry Equipment, Kewi Services B.V., Mikrobiologisches Labor Dr. Michael Lohmeyer GmbH, Rottmann Group GmbH, PTC Phage Technology Center GmbH, Stichting Aeres Groep, Wind plus Sonne, Whysor B.V. and ZLTO.