Organic fertilizers made from biological waste are still an unknown problem. According to studies, organic fertilizers serve as gates for microplastics in the environment. Researchers have discovered a large number of plastic particles in individual samples of salami.
Why does plastic get into salami?
Plastic is contained in household and industrial waste and cannot be completely removed from food. The implications of using plastic in fertilizers for soil organisms are still unclear.
Plastic is found almost everywhere: tiny particles float in lakes, rivers, and even in the deep sea. They pollute fish and are found in honey, sausages and drinks. Also in soils, the so-called "microplastic" is increasingly found.
Plastic particles with a diameter of less than 5 millimeters are formed as a result of the decomposition of plastic waste. They also enter the environment through cosmetics, clothing and wastewater.
Plastic in biological waste
Scientists from the University of Bayreuth have discovered yet another way for plastic particles to enter ecosystems: through organic fertilizers. These fertilizers are derived from biowaste found in households, industry, or agriculture.
Problem: Residues, manure and other waste may be contaminated with plastic. It is difficult to completely remove these residues during processing. Even Germany, a country with one of the most stringent rules in the world, allows up to 0.1% of the weight of plastic in the final product. But how much microplastics is really contained in supposedly environmentally valuable fertilizers?
Plastic everywhere
To test this, scientists analyzed two systems for the production of organic fertilizers:
- a system that operates in the absence of oxygen;
- a system that operates under oxygen conditions and where methane is produced.
Both systems produce organic fertilizers that have been analyzed for plastic content. Scientists have also investigated commercially available fertilizers.
Result: all samples contained 2 to 5 millimeters of small plastic particles. However, the amount of these residues falling into fertilizers fluctuated greatly. The differences directly depended on the type of fertilizer and the processing method.
Organic Salami - The Most Hazardous Product
The German manufacturer began to recall various types of salami, because foreign bodies were discovered in it. According to the manufacturer, the parts found are classified as "hazardous to health."
In Russia in 2014, a high content of plastic substances in sausages was discovered.
Foreign bodies are small blue plastic particles. Most often, they are found in salami from lamb, dried in the air. According to the manufacturer, it cannot be ruled out that these plastic parts may be contained in other salami.
In food production, contamination or foreign bodies may reappear due to errors in manufacturing processes. This can sometimes lead to injuries and health complaints when consumed.
Depending on the size, condition and material of the swallowed body, wounds in the mouth and throat may occur. Swallowed plastic parts can - depending on size - block the esophagus or digestive system.
If smaller parts remain in the body, they can sometimes cause inflammation. Also, digestive or stomach problems and internal injuries cannot be ruled out.
Underestimated problem
The results of the study show that the effect of microplastics on humans is significantly underestimated. Thanks to the fertilizer, plastic particles can spread in the soil and come into contact with living things. What consequences this has, according to scientists and their colleagues, is still completely unclear.
However, it cannot be ruled out that microplastics can accumulate in the body through the food chain and cause health problems. Further research is needed to further examine the importance and potential consequences of microplastic contamination with organic fertilizers.
