Reviewed by Lexie CornerFeb 12 2025
Two studies by Rutgers Health highlight how micro- and nanoscale plastic particles in soil and water can increase the absorption of toxic chemicals by plants and human intestinal cells, raising concerns about food safety.
The first study, published in NanoImpact, found that lettuce exposed to both nanoscale plastic particles and environmental pollutants, such as arsenic, absorbed significantly higher levels of toxins than plants exposed to the pollutants alone. A related study in Microplastics reported similar effects in human intestinal tissue.
Both studies suggest that micro- and nanoplastics, which form as plastics degrade in the environment, may contribute to a cycle of contamination. When plants absorb higher levels of toxic chemicals, these contaminants can transfer to humans through consumption, increasing potential health risks, particularly for vulnerable populations.
We have already put about 7 billion metric tons of plastics into the environment that keep breaking apart. They pollute everything around us – the water we drink, the food we eat, the air we breathe.
Philip Demokritou, Study Senior Author and Director, Nanoscience and Advanced Materials Center at Environmental Occupational HealthSciences Institute, Rutgers University
Researchers from Rutgers, the Connecticut Agriculture Experiment Station (CAES), and the New Jersey Institute of Technology (NJIT) used a human small intestine cellular model along with a lab-based gastrointestinal system. Their findings showed that nano-sized plastic particles increased arsenic absorption by nearly six times compared to arsenic exposure alone. The same effect was observed with boscalid, a widely used pesticide.
The presence of pollutants also increased plastic uptake by intestinal tissue, with absorption approximately doubling when toxins were present.
“We know nanoscale materials can bypass biological barriers. The smaller the particles, the more they can bypass biological barriers in our bodies that protect us,” Demokritou added.
In the plant study, lettuce was exposed to polystyrene particles (20 and 1,000 nanometers) along with arsenic and boscalid. The smaller particles had the greatest impact, increasing arsenic uptake into edible tissues nearly threefold compared to plants exposed to arsenic alone. These effects were observed in both hydroponic and soil-based conditions. Imaging and analytical tools confirmed that plastic particles accumulated in plant tissues, with smaller particles more likely to travel from roots to shoots.
Micro and nanoplastics form as larger plastic waste gradually breaks down in the environment.
“Even if we stop today producing plastics or using plastics, we have plenty of plastic waste unfortunately out there,” Demokritou added.
The study was part of a broader USDA-funded project investigating food safety concerns related to micro and nanoplastics. Researchers emphasized the need for further studies to understand long-term effects and develop mitigation strategies.
Demokritou further stated, “We need to stick with the ‘three-R’ waste hierarchy–reduce the use of plastics, reuse, recycle. For areas where you cannot apply these three Rs, like in agriculture where so much plastic is used for weed control and other things, use biodegradable plastics.”
The team is working on biodegradable alternatives to conventional plastics and developing technologies to detect and measure plastic particles in food and water. However, they stress that preventing further contamination should be a priority.
Demokritou concluded, “It is not that technically we cannot address some of these issues. But it will definitely be a challenge to retain all the benefits from this very useful material while reducing the harm that it does. There are social and economic obstacles related to plastic production and use to overcome.”
Journal References:
Bui, T. H. et. al. (2025) Micro-nanoscale polystyrene co-exposure impacts the uptake and translocation of arsenic and boscalid by lettuce (Lactuca sativa). NanoImpact. doi.org/10.1016/j.impact.2025.100541
Kharaghani, D. et. al. (2025) Ingested Polystyrene Micro-Nanoplastics Increase the Absorption of Co-Ingested Arsenic and Boscalid in an In Vitro Triculture Small Intestinal Epithelium Model. NanoImpact. doi.org/10.3390/microplastics4010004