PubMed · 2026-06-11
Tiny plastic particles in garden and farm soil disrupt the community of beneficial microbes around plant roots, weakening plants' ability to absorb nutrients and cope with stress. A review of 32 studies found that even 'biodegradable' plastics cause serious damage — and the full long-term consequences are still unknown.
Bacterial richness dropped 9–10% when plants were exposed to high concentrations of polylactic acid (PLA) — a common 'biodegradable' plastic — showing eco-friendly plastics are not necessarily soil-safe.
Beneficial plant-growth-promoting bacteria declined significantly (p < 0.05) when microplastics were combined with antibiotics, suggesting real-world co-contamination scenarios may be especially harmful.
Biodegradable microplastics (PLA, PBAT) shifted microbial communities toward fast-growing, nutrient-hungry bacteria and disrupted genes responsible for soil nutrient cycling, altering fundamental soil fertility processes.