Plastics are widely employed in agriculture, from plastic-coated seeds to protective covers used to control soil temperature and weed development over crops.
These synthetic materials are also employed in irrigation tubes, sacks, and bottles, as well as in biosolid fertilizer that is dispersed on fields.
Plastics are piling up in soil across the world
While many of these products have helped enhance crop yields, the paper warns that there is emerging evidence that degraded plastics are polluting the soil and negatively harming biodiversity and soil health, as per UN News.
Furthermore, microplastics, such as those found in some fertilizers, have an influence on human health when they enter the food chain.
Professor Elaine Baker of the University of Sydney, the report's co-author, stated that agricultural land is limited.
We are beginning to learn that the accumulation of plastic can have far-reaching consequences for soil health, biodiversity, and productivity, all of which are critical for food security.
According to UNEP scientists, large pieces of plastic can break down into shards smaller than 5 mm long over time and penetrate into the soil.
These microplastics can alter the physical structure of the soil beneath our feet, limiting its ability to store water. They can also have an impact on plants by inhibiting root development and nutrient absorption.
Fertilizers made from organic materials, such as manure, are now the single-largest cause of microplastic contamination in soil.
Although they are less expensive and better for the environment than produced fertilizers, the manure is combined with the same plastic microspheres that have been found in certain soaps, shampoos, and cosmetic products.
While some nations have prohibited the use of these microspheres, additional microplastics continue to reach our water systems through discarded cigarette filters, tire components, and synthetic garment fibers.
According to the paper, efforts are being undertaken to increase the biodegradability of polymers used in agricultural goods.
However, certain protective films, which are intended to prevent moisture loss, are currently sold as completely biodegradable and compostable, which is not necessarily the case.
Bio-based polymers are not always biodegradable; some may be as harmful as fossil-fuel-based polymers; and cost remains a concern.
The authors of the research recommend using 'cover crops,' which protect the soil and are not intended to be harvested.
These natural remedies can suppress weeds, combat soil diseases, and improve soil fertility, but UNEP warns that they may diminish yields and raise costs.
However, the expert advises governments to "disincentivize" the use of agricultural plastics, following in the footsteps of the European Union, which limited the use of some types of polymers in fertilizer earlier this year.
Read more: How is Climate Change Impacting Agriculture Commodity Prices?
Nanoplastics' Effects on Crops and Terrestrial Plants
Crops, which are critical components of the food supply chain, have the ability to absorb and retain hazardous nanoparticles from the environment, as per AZO Nano.
However, in terms of nanoplastic toxicity, terrestrial environments have lately garnered substantially less scientific attention than their aquatic counterparts.
According to certain studies, nanoplastics may enter plant roots and reach the leaves. PS-NPs (polystyrene nanoplastics) can enter plant cells through fractures in wheat and lettuce crops.
Furthermore, charged nanoplastics have the capacity to agglomerate and impede the growth and reproduction of a wide range of terrestrial plants.
Consumption of nanoplastic-contaminated agricultural grains can potentially be hazardous to human health.
Although recent research has analyzed nanoplastic entrance, dispersion, and cytotoxicity in crops, little is known about nanoplastic deposition and activities inside seeds, which constitute the biosphere's essential living ingredient at the lowest nutritional level of the food chain.
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