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Beyond PFAS to Plastics: The Emerging Contaminant that Lies Ahead

Mark McDaniel and Thomas Parker Redick


  • Defines microplastics and nanoplastics and discusses their regulation.
  • Addresses creating a proactive mitigation plan that clearly demonstrates steps that are being taken to study and potentially reduce risk.
Beyond PFAS to Plastics: The Emerging Contaminant that Lies Ahead
Giovanni Bortolani via Getty Images

For food and agriculture, the problem of plastics in food and the environment pose special challenges. Research into what effects these food contaminants might have on human health is just getting underway. This research will lead to cases filed by the plaintiffs’ bar, as well as increasing the attention of state and federal environmental and food safety regulators. The steady increase in microplastics detection and their ever-present levels in the world’s oceans, biota, and drinking water means that people everywhere will have to address these risks. The parallels, in terms of ubiquity and uncertainty of health safety, are striking with the emerging per-and polyfluoroalkyl substances (PFAS) debacle that has triggered headlines and increasing litigation and regulation.

Microplastic: What Does It Mean?

The word “plastic” includes various synthetic compounds, generally derived from petroleum. While there is no universal definition of microplastics, most definitions focus on size under 5 millimeters (.2 inch) in length occurring in the environment as a consequence of plastic pollution.” Kara Rogers, “Microplastics,” Encyclopedia Britannica (Sept. 8, 2020).

Researchers have also defined a lower bound of one nanometer (there are one million nanometers in just one millimeter: how’s that for small?)—with microplastics smaller than that being considered nanoplastics. Andrew J. Scholz et al., Microplastics: The Looming Challenges, Pitfalls, and Uncertainties Facing the Regulated Community and Beyond, 63 For the Defense 36–40 (June 2021). As for their formation, “microplastics can come from the breakdown of plastic objects, car tires, and polyester clothing,” as well as from originally manufactured products such as microbeads found in cosmetics, personal care products, and cleaning scrubs. A. Dick Vethaak, and Juliette Legler, Microplastics and Human Health, 371 Science, 672–74 (2021).

Because microplastics are small and often the weathered remnants of their original product, it can be extremely difficult to trace them back to their source. Still, it is useful to try to trace plastics back to their original products by examining their size, color, and shape. Agricultural runoff may incorporate microplastics degraded from greenhouse films, plastic mulch, irrigation systems, seed bags, and planters. Other sources include industrial spills and runoff from industrial processes, leaking vehicles, yards, recycling facilities, and landfills.

In 2019, the world’s production of plastics totaled approximately 368 million metric tons, with China standing out as the largest plastics producer in the world. Ian Tiseo, Global Plastic Production 1950–2019, Statistica (2021). While China is the world’s largest manufacturer of plastics, the United States is the largest generator of plastic waste, producing approximately 42 metric tons in 2016. Kara Lavender Law et al., The United States’ Contribution of Plastic Waste to Land and Ocean, 6 Science Advances, (Oct. 2020).

It’s estimated that 10 million metric tons of plastic end up annually in the oceans, where marine animals consume them. Indeed, plastic waste is now found on beaches in the most remote places on Earth.

Duel Potential Concerns: Environmental and Toxic Tort

Microplastics present the dual concerns of  environmental cleanup and remedial considerations, as well as the specter of potential human health effects that could lead to future toxic tort exposure. Rumblings that microplastics may be the next mass tort litigation may seem a bit premature, but environmental litigation is already afoot using traditional common law theories of public nuisance and violations under federal statutes. Douglas A. Henderson et al., INSIGHT: Is Plastics Litigation the Next Public Nuisance?, Bloomberg Law (April 23, 2020), (suits involving marine animals).

As far as human health issues, recent attention has focused on potential human exposure to microplastics, primarily via ingestion. Notably, the long-term effects of microplastic ingestion are not well understood yet. In September 2019, the World Health Organization stated that microplastics, “don’t appear to pose a health risk at current levels,” but cautioned that the available information was limited, and more research was needed to determine how microplastics affected human health.

Regardless of whether the finding is accurate based on the study, the effect of such ingestion of microplastics remains an open question, given the lack of toxicological and epidemiological research. This parallels the lack of understanding with health effects of low doses of PFAS.

Microplastics and Nanoplastics: Facts

A study commissioned by the World Wild Fund for Nature and conducted out of the University of Newcastle, Australia, found that the average person could be ingesting approximately five grams—the equivalent of a credit card’s worth—of microplastics per week. See Revealed: Plastic Ingestion by People Could Be Equating to a Credit Card a Week, WWF (June 12, 2019). A groundbreaking study recently found that 39 percent of household dust in Australia is microplastics and nanoplastics. The study data reveal that these plastics are prevalent in Australian homes and that the greatest risk of exposure resides with young children. Neda Sharifi et al., Quantification and Exposure Assessment of Microplastics in Australian Indoor House Dust 283 Environmental Pollution 227064 (Aug. 25, 2021),

Micro- and nanoplastics enter into the human food chain in various ways. They emerge on farms, crops, and in the meat and milk of farm animals, which then become readily available for human consumption. This is particularly true where a farm uses sewage sludge for fertilizer and organic amendment to agricultural soils. Contamination also commonly occurs in food production processes and in leaching from plastic food and drink packaging. To date, micro- and nanoplastic fragments have been detected in honey, beer, salt, sugar, fish, shrimp, and bivalves. Experimental sampling on tap, bottled and spring waters showed that microplastics are present in all these water sources. Tap water from 159 global sources was tested and 81 percent were found to contain microplastic particles measuring less than 5 mm. Tests were conducted on 259 individual bottles of water from 11 different brands and 27 different batches, and the results demonstrated that 93 percent contained microplastic particles. Mouse studies showed health effects from plastics, but human epidemiology is lacking. Maxine Swee-Li Yee et al., Impact of Microplastics and Nanoplastics on Human Health, 11 Nanomaterials 496 (2021),

When (perceived) risk exceeds regulation, litigation often fills the gap. This is partially due to public perception traveling faster than the science. Solutions are often complex, and therefore take longer than the public wants, creating a need for resolution. For example, MTBE (methyl tert-butyl ether) was introduced in the early 2000s as a gasoline additive that improved octane performance—until it was phased out less than a decade later because of toxicity fears. Similarly, the use of Bisphenol-A (P=BPA), a common ingredient in food container linings, has steadily declined in the face of concerns about adverse effects on fetuses, newborns, and developing children. We currently see this trend in increasing lawsuits surrounding PFAS and multidistrict litigation cases.

Regulation of Microplastics and Nanoplastics

Plastic regulation currently involves reduction, reuse, and recycling and is mostly focused on single-use plastics. There are also potential alternatives in the form of biodegradable plastic derived from corn, soybean, and other renewable resources.

Single-use plastics regulations already exist in eight states, the European Union, China, 10 US cities, state of California drinking water and most recently, Canada. According to the Canadian government, the country’s residents use some 15 billion plastic bags each year and nearly 57 million straws every day, contributing to the annual generation of more than 3 million metric tons of plastic waste. The vast majority of this plastic is never recycled. Instead, most of it winds up in landfills, incinerated, or dumped directly into the environment, endangering wildlife, and polluting ecosystems with hazardous chemicals.

Canada’s new rules were first proposed in October 2020 as part of a plan to achieve zero plastic waste by 2030. Canadian businesses will have until December of this year to stop producing or importing six categories of single-use plastic: grocery bags, cutlery, straws, dishware, stirrers, and the six-pack rings used to hold together beer cans and other beverages. To give businesses enough time to use up their existing stock and adapt, a ban on the sale of these products will not go into effect until December 2023.

The United Nations recently approved a landmark agreement to create the world's first ever global plastic pollution treaty. This is a resolution to address the full life cycle of plastic, including its production, design, and disposal and has been endorsed at the United Nations Environment Assembly (175 Nations), with the goal of producing an international legally binding agreement by 2024.

We will continue to see attempts at regulation by litigation, especially where legislative initiatives have stalled.

Proactive Mitigation (What Your Client Can Do Now)

In the face of all this activity, what is a client involved in plastics production and use to do? For starters, creating a proactive mitigation plan that clearly demonstrates steps that are being taken to study and potentially reduce risk will help. This plan should:

  • Assess exposure to risk and litigation related to micro and nanoplastics.
  • Assess insurance exposure, especially historically.
  • Find and preserve key employee knowledge.
  • Audit current and former properties, whether owned or leased, to assess potential risk and liability.
  • What does the science say? How much and what quality data is out there? Is it persuasive?
  • Standardize sampling and analytical methodologies by working with researchers and labs.
  • Assess the availability of expert witnesses and lock them in early.
  • Fund in-house and independent research and studies (this shows transparency and proactiveness).
  • Evaluate substitutions very, very carefully (the messes made by Methyl tertiary-butyl ether (MTBE) and bisphenol-A (BPA) are both examples of substitutions that had their own problems).
  • Develop your alternative management approach.