Occurrence of Plastic Micro- and Nano-Particles in Specialty Crop Production

Key Takeaways:

While micro and nanoplastics are ubiquitous in the environment, health agencies worldwide do not link their presence in the environment with a risk to human health.
Micro and nanoplastics are often found in shellfish and other seafoods.
In the US, major sources of microplastics in the production environment (biosolids, urban run-off, heavily contaminated surface waters) are already excluded from fruit and vegetable production for FSMA compliance.
The majority of reports of microplastics in crop production environment are from Asian countries where overall environmental contamination with plastic waste is alarming. Results of these surveys should not be extrapolated to other regions.
Even when present in soils, most microplastics are not taken up by plants. Some nanoplastics that can be taken up by plants were derived from materials like Styrofoam, which is already being phased out.

Executive Summary

Microplastics (MPs) and nanoplastics (NPs) are ubiquitous in the environment and this presence in the environment and in certain foods increasingly draws attention from consumers and regulators. Public health agencies like the US FDA, Health Canada, and the WHO acknowledge the presence of MPs and NPs in the food supply but emphasize that current scientific evidence does not conclusively show a risk to human health. In the United States, the only direct legislation targeting microplastics is the Microbead-Free Waters Act of 2015 (Public Law 114-114), which bans plastic microbeads in rinse-off personal care products. Broader regulation of MPs and NPs in agriculture, food, and water remains limited, although California requires monitoring and formal definitions for microplastics in drinking water. The European Union has taken a more proactive approach, setting a goal to reduce the presence of MPs in the environment by 30% by 2030 through regulatory actions, while still calling for further study on potential health and environmental effects. Currently, there are no established regulatory limits for MPs or NPs in fresh produce, and public health agencies globally have not yet determined whether existing levels pose a significant health risk. In the US, measures put in place under Food Safety Modernization Act (FSMA) and regulations governing USDA Organic Production indirectly limit introduction of MPs and NPs by putting restrictions on uses of certain soil amendments and management of agricultural water.

MPs have been commonly detected in seafood, meat, honey, and sea salt. We note that retail samples of fresh produce have been very limited, collected from local farmers markets. Data obtained from these samples is difficult to meaningfully interpret as the reported values from independent studies differ by ~100,000 fold. Around the world, plastic particles can be hypothetically introduced into the fresh produce production environment through various routes, including soil amendments, irrigation water, air deposition, and packaging materials. Occurrence and amounts of MPs and NPs in the crop production environment appear to depend on local environmental conditions and production practices, and most well publicized surveys have been carried out in Asia and Europe. Washing produce has been reported to reduce the number of microplastic particles on surfaces.

While field surveys reported the presence of microplastic particles in the field, laboratory studies on the impact of plastic particles on edible plants typically use much smaller nanoparticles (1-1000 nanometer in size). These laboratory reports indicate that under some laboratory conditions, when present in high concentrations in aquatic suspensions, certain nanoparticles can be taken up by plants. However, these studies often use artificially high concentrations or idealized exposure models, or types of plastic particles that are either unlikely to occur in fields or results from plastics that are already being phased out by the industry. Importantly, detecting and measuring MPs and NPs in soil, water, and plant tissue remains technically challenging, with no universally accepted testing standards. As a result, findings from published studies vary widely and should be interpreted with caution.

Download full report

Occurrence of Plastic Micro- and Nano-Particles in Specialty Crop Production

Key Takeaways:

Related Resources