Food security and soil health: the United Nations calls to stop the flow of micro and nano-plastics into the environment

The United Nations Environment Program (UNEP) has publié this day a “prospective file” (“Foresight brief”) dated July, which warns of the massive use of plastics in the field of agriculture, and underlines their harmful impact on soil health, biodiversity and our food security. 

This Foresight Brief, published each year by the agency to discuss specific contemporary environmental issues, concludes on the need to adopt the precautionary principle and to develop targeted solutions to stop the flow of micro and nano-plastics into the environment. 

Agriculture, now an important source of micro and nano-plastics

The evolution of agricultural practices towards an intensive model has been accompanied by the increasing use of plastic in agriculture, and therefore an increase in polluting waste. 

UNEP distinguishes the different sources of these micro and nano-plastics in agricultural activities:

•  decomposition of plastic products
• spreading of sludge from wastewater treatment plants contaminated with nano and microplastics. 
• polymers used to coat slow release fertilizer granules and seeds.

Risks to our health and that of the environment

The dossier also highlights the environmental risks of micro and nano-plastics, in particular on the structure and activity of the soil, and the health risks, due in particular to the impact of these plastics on the food chains. This file echoes a investigation report previously published in December 2021 by the Food and Agriculture Organization of the United Nations (FAO), which was already sounding the alarm on the “disastrous” (sic) use of plastics in agriculture and calling for action to drastically limit the threat they pose to food security, human health and the environment.

Another report published in May 2022 by the NGO SKY (Center of International Environmental Law) addresses more specifically the growing use of fertilizers and pesticides coated in polymers and their propensity to exacerbate the harmful effects already induced by the use of these products.¹See the study cited on page 9 of the report “Pesticide Encapsulation at the Nanoscale Drives Changes to the Hydrophobic Partitioning and Toxicity of an Active Ingredient,” Matthew Slattery, Bryan Harper, and Stacey Harper, Nanomaterials 9, no. 1 (January 2019). Conducted in 2019 by researchers at Oregon State University, it reveals that a conventional insecticide whose active ingredient is encapsulated in nano-sized plastic is more toxic than applying the same active ingredient with a larger plastic capsule or without any encapsulation..

UNEP recommendations

Among its recommendations, UNEP is today calling on governments to discourage the use of plastics in agriculture, by improving regulations and standards on agricultural products - including fertilizer and seed coatings.

In Europe, a restriction of micro and nano-plastics under discussion

Due to concerns for the environment and human health, ECHA has proposed in 2017 a far-reaching restriction for micro and nano-plastics in products placed on the EU/EEA market in order to avoid or reduce their release into the environment. In addition to the agricultural sector, which represents the majority of micro and nano-plastics used and generated, these can also be intentionally integrated into mixtures used in cosmetics, cleaning products, in paints, etc.

In 2022, this restriction is still not in force, hampered by the industrial lobbying, which notably tried to exclude nano-plastics (<100 nm) from the scope of this restriction. The recent proposal from the European Commission, which requires amending the list of substances restricted under Annex XVII of REACH was discussed at a closed meeting of the Commission's REACH Committee on 23 September. AVICENN remains attentive to the evolution of this restriction.