Microplastics in Soil a ‘Trojan Horse’ for Toxins
Microplastics act like a “Trojan horse,” delivering pollutants, pesticides, and bacteria through the soil, a five-year multinational research project has found. Read more on E360 →
Microplastics infiltrate soil, acting as a "Trojan horse" for toxins, a five-year study across Europe has revealed. Conducted with EU funding, the research analyzed 227 agricultural fields in 11 countries and detected microplastics in every sample. This poses a significant global threat, as healthy soils are vital for life on Earth.
The contamination often reflects both modern farming practices and historical land use, indicating that plastic pollution can endure for many years. Microplastics can interact with other stressors like pesticides and veterinary drugs, amplifying their impact. One Swiss study found that fields with the highest levels of tire-wear particles also exhibited the highest levels of other toxic chemicals and metals.
Microplastics create new microbial habitats on their surfaces, known as the "plastisphere," which serves as a hotspot for interactions between plastics, microbes, and agrochemicals. Research has found an increase in antibiotic-resistant genes in these environments. The smaller the microplastics, the more likely they are to adsorb pollutants, microbes, and DNA, a phenomenon dubbed the "Trojan horse effect."
This effect can disrupt critical soil processes, such as nutrient cycling, and harm earthworms, which play a vital role in shaping soil microbiomes and ecological functions. Microplastics can also negatively affect plant growth and function, reducing leaf area, chlorophyll content, photosynthetic efficiency, and plant biomass. The effects become more pronounced under drought conditions.
Environmental assessments often consider pollutants individually, but this study highlights the need for a broader policy approach that recognizes the complex interactions between plastic contamination and other soil degradation factors. While biodegradable plastics are being used as an alternative, the research found they are not necessarily safer, as they can still degrade into microplastics that pose ecological risks.
To safeguard long-term food production and soil health, policymakers must act swiftly to implement standardized plastic monitoring, enhance manufacturer transparency, and conduct comprehensive risk assessments evaluating microplastic interactions with co-pollutants and various species.
Written by urgent.news from Yale Environment 360's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
