Plastics are used widely in agriculture, from plastic-coated seeds to protective films used to regulate soil temperature and prevent weed growth on crops.
These synthetics are also intentionally added to biosolids, spread in fields, and used in irrigation pipes, sacks and bottles.
Seedlings are covered with nylon.
Biodiversity, health impact
While all of these products have helped increase crop yields, there is growing evidence that biodegradable plastics are polluting the soil and affecting biodiversity and soil health, the report warns. .
Furthermore, microplastics, such as those used in some fertilizers, are also affecting human health when transferred to humans through the food chain.
“There is only a finite amount of farmland,” said co-author Professor Elaine Baker from the University of Sydney. “We’re beginning to understand that plastic accumulation can have widespread effects on soil health, biodiversity and productivity, all of which are critical to food security.”
Microplastics come in a wide range of sizes, colors and chemical compositions, and include fibers, flakes, pellets, flakes, sheets or foams.
Everything is affected by plastic
UNEPExperts explain that over time, large pieces of plastic can break into pieces less than 5mm long and seep into the soil.
These plastics can change the physical structure of the earth beneath its feet and limit its ability to hold water. They can also affect plants by reducing root growth and nutrient absorption.
Currently, the biggest source of microplastic pollution in soil is fertilizers produced from organic matter such as manure.
While these may be cheaper and better for the environment as a result of fertilizer production, manure mixed with the same plastic microspheres is known to be commonly used in some soaps, shampoos and other products. makeup products.
While some countries have banned these microspheres, other microparticles continue to enter our water systems through discarded cigarette filters, tire components and synthetic clothing fibers. .
A girl runs through desolate farmland in the Sagaing region of Myanmar.
For what?
The report highlights that progress is being made to improve the biodegradability of polymers used in agricultural products.
However, some protective films – used to prevent moisture loss – are currently marketed as fully biodegradable and compostable, which is not always the case. so.
Bio-based polymers are not necessarily biodegradable, some can be as toxic as fossil fuel-based polymers, and their price remains an issue.
One solution proposed by the report authors is the so-called ‘cover crop’, which covers the soil and is not intended for harvesting.
UNEP warns these nature-based solutions can suppress weeds, fight soil diseases and improve soil fertility, but there are concerns they could reduce yields and increase costs. .
“None of these solutions is a magic bullet. “Plastics are inexpensive and easy to use, which makes trying to introduce substitutes difficult to sell,” explains Ms. Baker.
However, the expert recommends that governments discourage “the use of agricultural plastics, which, in line with the European Union, earlier this year restricted certain polymers used in fertilizers.
“Now is the time to apply the principle of prevention and develop targeted solutions to stop the flow of plastic from the source and into the environment,” emphasized the Australian scientist.
