New research has revealed that plastic pollution is no longer confined to oceans and urban waste sites, but is now entering agricultural systems and affecting food crops. Scientists have found that tiny plastic particles in soil can be absorbed by plants like wheat and tomatoes, potentially disrupting their growth and raising concerns about food safety.
The study conducted by researchers at Griffith University in Australia, examined how plastic particles behave in farm-like soil conditions. Using wheat and tomato plants, scientists observed how plastics of different sizes interact with roots and soil.
They found that larger plastic particles tend to remain trapped around plant roots, while smaller particles, especially nanoplastics, can travel deeper into the soil and even enter plant tissues. These tiny particles were detected in roots, stems and, in some cases, even leaf structures, indicating that plastics can move through a plant’s internal system.
This discovery suggests that agricultural soil is not just a storage site for plastic waste but also a pathway through which plastics can enter the food chain.
Tomato plants found to be more vulnerable
Among the crops studied, tomato plants showed significantly higher levels of damage compared to wheat. When exposed to fibrous plastic particles, tomato plants experienced a sharp decline in growth.
Under high exposure conditions, tomato shoots decreased by nearly 67 percent, roots shrank by 47 percent, and overall root biomass dropped by 82 percent. Wheat plants were less affected but still showed a noticeable reduction in root length, indicating that plastic exposure impacts plant health across different crop types.
Researchers explained that shorter and weaker roots reduce a plant’s ability to absorb water and nutrients, ultimately limiting its growth and productivity.
Fibrous plastics create physical stress on roots
The study highlighted that fibrous plastics such as those from synthetic textiles are particularly harmful. These long strands tend to tangle around roots and root hairs, physically blocking the uptake of water and nutrients.
This mechanical interference creates stress for plants even before chemical effects come into play. In addition, plants exposed to plastic fibers showed reduced chlorophyll levels, meaning their ability to perform photosynthesis was also affected.
The research also found that the presence of different types of plastic particles together can worsen the impact. This suggests that real world plastic pollution, which usually involves a mix of materials may have stronger and more complex effects than previously understood.
Weathered plastics pose greater risks
One of the key findings of the study was that aged or weathered plastics are more likely to enter plant systems than fresh plastic particles. Over time, exposure to sunlight, heat and environmental conditions changes the surface properties of plastics, making them more reactive and easier for plants to absorb.
This means that older plastic pollution present in agricultural soils may pose a greater long-term risk to crops.
Researchers noted that the levels of plastic particles observed in the study are similar to those found in real agricultural fields, especially those treated with sewage sludge used as fertiliser. Such sludge often contains microplastics, particularly fibers from synthetic clothing that survive wastewater treatment processes.
This explains why fibrous plastics are commonly found in soils where crops are grown.
Implications for food safety and agriculture
Scientists emphasised that more research is needed to determine whether these particles accumulate in fruits, grains and vegetables that people consume. However, the fact that plastics can move from soil into plant tissues already closes an important gap in understanding how pollution spreads through ecosystems.
The findings highlight a growing challenge for farmers, policymakers and environmental regulators. Plastic pollution in soil is not only affecting plant growth but may also have long-term implications for food security and human health.