Coastal microplastics are related to higher disability rates

The microscopic plastic debris that flows into our oceans may quietly affect human health in ways researchers have just begun to understand. People living in coastal areas with high marine microplastics in coastal areas face increased disability rates that affect memory, mobility and independent living, a new study found.

The preliminary findings will be presented at the 77th annual meeting at the American College of Neurology in April, suggesting a pattern on how these nearly invisible pollutants affect U.S. coastline communities.

The study compared 218 coastal counties in 22 states and studied the prevalence of disability associated with nearby ocean microplastic levels. Although the study does not prove causality, it adds to increasing evidence that environmental pollutants play a more important role in nerve and physical health than previously recognized.

“The environment may play a crucial role in our health, and the contamination factor may affect a person at Lahey Hospital and Medical Center in Burlington, Massachusetts.

Marine microplastics (plastic debris less than 5 mm) penetrate almost every marine ecosystem on Earth. These particles are derived from degraded plastic waste and products such as facial scrubs, fishing nets and food packaging, creating an environmental pollutant that may be discovering new avenues of human biology.

Gradients of influence

The research team divided the coastal counties into four groups based on the concentration of microplastics in adjacent seawater, ranging from low (less than 0.005 blocks per cubic meter) to very high (more than 10 pieces per cubic meter). The differences between extremes are distinct – the county level is very high on average over 1,000 micro-fragments per cubic meter, while the average for those with lower levels is less than 10.

What emerges is a consistent pattern of multiple types of disability. Among counties with the highest levels of microplasticity, thinking and memory disorders affected 15.2% of residents, compared with 13.9% of the lowest levels. Similar patterns occurred in the emergence of travel disorders (14.1% vs. 12.3%), self-care disability (4.2% vs. 3.6%) and independent living disorders (8.5% vs. 7.7%).

The association persisted when researchers adjusted for potential confounders, including heart disease, stroke, depression, air pollution, and socioeconomic variables. The counties with the highest microplastic pollution show a 9% higher rate of cognitive impairment, a 6% increase in self-care disability, a 16% increase in self-care disability and an 8% increase in self-care disability compared with microplastic areas.

“We found in coastal communities where there are higher levels of microplastics in the water, with higher disability rates, which can influence a person’s life in a variety of ways through thinking and memory, movement, and their ability to take care of themselves and live independently,” Garnatala noted.

Complex distribution

The distribution of microplastics in coastal waters is not uniform and is affected by complex factors including ocean currents, population density, waste management practices and industrial activities.

Ganatra elaborates on this complexity, noting: “The amount of plastic in different regions may vary due to ocean currents, and ocean currents can carry and concentrate plastics in certain regions. Other factors such as population density, local waste management and industrial activities may also play a role. The reasons are complex and may involve multiple environmental and human-related factors, but this relationship requires further research to be fully understood.”

This uneven distribution may help explain why some coastal communities seem to be more affected than others, although the researchers warn that the study represents only a snapshot of time, rather than a longitudinal analysis tracking changes over time.

From pollution to public health

Self-care disorders measured in the study included difficulties in dressing, bathing or navigation at home, while independent living disorders included challenges in managing finances, shopping or using transportation – all basic aspects of daily operations can affect the quality of life.

The underlying mechanisms in which microplastics may affect health are unclear. However, previous laboratory studies have shown that these particles can cross biological barriers and may trigger inflammatory responses or disrupt cellular processes.

“These findings provide insights on how marine microplastics affect brain health,” Ganatra said. “More research is needed to further explore this link and examine the overall public health impact of microplastic pollution.”

Although this study does not explicitly demonstrate that microplastics can cause disability (expressing only one association), it raises important questions about the downstream health effects of environmental pollutants that are ubiquitous in modern ecosystems.

The study is as plastic production continues to accelerate globally, with an estimated 11 million tons entering the ocean each year. As these materials break down into smaller and smaller particles, their potential to interact with living systems may expand, creating public health challenges that go far beyond visible pollution.

For coastal communities already in an increasing number of ocean and climate change-driven extreme weather, this emerging evidence suggests that another invisible threat may affect its most vulnerable residents, a way to connect the environment and human health, requiring further investigation.