Plastics in agrifood systems: From field to fork – and back again

The word "plastics" in agrifood systems tends to conjure supermarket shelves – shrink-wrapped vegetables, single-use bags, blister-packed fruit. This is a misleading place to start. The story of plastics begins far upstream, in oil and gas fields, where raw materials are extracted and processed into polymers that eventually enter agricultural systems as mulch films, silage wraps, and irrigation pipes. From there, plastics continue their journey beyond the farm to the market, fragmenting and moving into soils, waterways, animals, human bodies, and broader ecosystems long after crops are harvested or packaging is discarded. It is a One Health problem – one that sits at the intersection of human, animal, and ecosystem health and cannot be solved by any single discipline acting alone. 

According to FAO, agrifood systems use an estimated 13.4 million tonnes of plastics annually in plant and animal production, and a further 37.3 million tonnes in food packaging. These flows are not discrete: plastics degrade and recirculate in less visible but more pervasive forms through soil, water, feed, and food, rather than leaving the system. Plastics are also vectors for chemical exposure: additives and other associated chemicals can migrate into soil, water, feed, and food, creating risks that extend beyond the particles themselves. 

At the farm gate: necessity and risk arriving together 

Crop production, forestry, and livestock account for over 10 million tonnes of plastic per year – roughly 2.8 percent of total global plastic production – followed by fisheries and aquaculture at 2.1 million tonnes. Applications range from mulching films and greenhouse covers to silage wrap, tree guards, drip irrigation, polymer-coated fertilizers, and protective fruit sleeves. 

The benefits are real. Plastic mulch increases yields in water-scarce conditions. Greenhouse films extend growing seasons. FAO is explicit: in the absence of viable and cost-effective product alternatives or practices, removing plastics from agriculture would in many contexts may reduce food production. Any honest policy conversation has to start there. 

In high-income countries, plastic use in agriculture is intensive and increasingly regulated. In smallholder contexts, for example across sub-Saharan Africa and South Asia, its use is more fragmented, less tracked, and accompanied by far weaker collection and recycling systems. Global demand for greenhouse, mulching, and silage films is projected to grow by roughly 50 percent by 2030  – much of it in regions least equipped to manage the waste. 

In the soil: The invisible accumulation 

Once laid on a field, plastic degradation begins immediately. UV radiation, temperature, and mechanical disturbance fragment macro-plastics into micro- and nanoplastics that accumulate in the soil – entering through direct breakdown, but also via biosolids (treated sewage sludge applied as fertiliser), which studies suggest may be one of the largest single sources of microplastics in agricultural land. 

A critical misconception in public debate: the primary plastic pollution crisis in food systems is not the ocean – it is the soil. Agricultural soils are estimated to receive far greater quantities of microplastics than the oceans, because 93 percent of global agricultural activity takes place on land. Soil microbiome disruption, reduced water retention, and harm to earthworms and pollinators are all documented pathways through which plastic accumulation degrades the foundations of food production itself.  

How plastics get back into food – and fuel new threats 

Microplastics do not stay in the soil. They re-enter food systems through multiple documented routes. A 2023 study of livestock and poultry feeds found microplastics in all tested samples; they have been detected in meat, milk, and blood from farm animals. In aquatic systems, bivalves, small fish, and crustaceans are confirmed vectors for microplastic exposure, with particles entering food webs from degraded fishing gear and plastic debris. 

Beyond direct contamination, there is a less visible but deeply concerning pathway: plastics as a driver of antimicrobial resistance (AMR). On plastic surfaces in soil and water, bacteria form biofilms that not only protect pathogens from environmental stress but accelerate the exchange of resistance genes between microorganisms. Plastic pollution may therefore act as both a disease vector and an environment where resistance traits can emerge and spread – a threat that connects food system contamination directly to one of global public health's most urgent concerns. 

Current evidence indicates that acute health risks from microplastics in food are likely low, but long-term effects from chronic exposure – especially to nanoplastics and chemicals that can migrate from plastics into food, remain uncertain and under active investigation; reliable dose-response relationships have not yet been established. Microplastics have been detected in human lungs, blood, and placentas, confirming widespread exposure though the full health implications are still unclear. FAO and WHO reviews stress major knowledge gaps, limited harmonized detection methods, and the need for more toxicological and exposure research before firm conclusions on long-term risk can be drawn.