Microplastics are a pervasive environmental issue, and their presence in Pennsylvania's water is a cause for concern. While it's known that plastic pollution reaches the ocean, the extent of plastic's impact before it reaches the ocean is less understood. As environmental engineers and scientists, we recently conducted a study to map the movement of microplastics through Pennsylvania's waterways, and the findings were striking.
Our research revealed that microplastics are nearly everywhere, with their concentration in sediment doubling every 20 years. Some of the most common types of microplastics are among the most toxic. Plastic pollution is a global issue, with global plastic production doubling every 20 years since the 1950s, reaching over 500 million tons annually. The U.S. is a leading producer of plastic pollution, generating over 48 million tons of plastic waste annually, with only a 5-6% recycling rate.
Microplastics are found in the air, water, soil, food, and living organisms, including humans. They enter the body through ingestion, inhalation, and skin contact. Studies have found microplastics accumulating in human blood, brain, and reproductive systems. Plastics are classified into seven categories using the resin identification code system, and more than 80% of mismanaged plastic waste is estimated to be transported by rivers to coastal environments.
Our study focused on Pennsylvania's Raystown Lake, Conemaugh River Lake, and the John Heinz National Wildlife Refuge, and we found that land use alone cannot predict microplastic concentrations. Estuaries do trap microplastics, but not enough to account for the ocean's missing plastic. The most abundant types of plastic found were polypropylene, polyurethane, and tire rubber, all single-use plastics.
Surprisingly, microplastic levels in a rural watershed in Raystown were similar to those in a watershed near Philadelphia International Airport. On average, we found about 1,125 microplastic particles per pound of sediment, but concentrations varied widely.
The good news is that recent sediment layers show a small but measurable decrease in microplastic concentration, possibly due to better recycling rates and awareness of plastic waste. To reduce exposure to microplastics, individuals can stay informed about health risks, check recycling numbers, and swap single-use plastics for alternatives like glass, stainless steel, or unbleached paper.
In conclusion, while the issue of microplastics is complex and far-reaching, there is a glimmer of hope. By understanding the problem and taking action, we can work towards a more sustainable future and reduce the impact of plastic pollution on our environment and health.
