Robert Carline
member of the Spring Creek Watershed Atlas Work Group
The information in the following article was taken largely from an article by Dr. Sherri Mason, which can be accessed through: https://www.americanscientist.org/article/plastics-plastics-everywhere and from an article by Faran Savitz, which is duplicated below.
Plastic products are everywhere. They are quite useful, nearly indestructible,
inexpensive, and they constitute a large portion of our solid wastes. In 2017 worldwide
production of plastics was about 440 million tons. About two-thirds of these products
were discarded, only 10% were recycled and about 15% ended up in solid waste
disposals. Unlike organic wastes that are subjected to microbial breakdown, plastics
are not affected by micro-organisms. But, plastic will degrade to some extent and
eventually end up as microscopic particles. Breakdown products include films,
fragments, fibers, and beads – collectively named microplastics.
These microplastics are a concern, because they are found in freshwater and
marine systems throughout the world and can be found in the atmosphere. These tiny
particles can be taken up by plants and then consumed by animals and humans.
Microplastics are frequently found in drinking water supplies and even in bottled water.
Perhaps it is not surprising that microplastics have even been found in human fetuses.
In aquatic systems, microplastics are taken up by microscopic plants and animals and
then passed up through the food chain, thereby reaching higher concentrations with
each successive consumption. This process is known as bioaccumulation.
Mason (2019) found microplastics in surface waters throughout the Great Lakes,
with the highest concentrations in Lake Ontario, which is the farthest downstream lake.
Savitz (2021) collected water samples from 53 surface water sites throughout
Pennsylvania and found microplastics at all sites (see article below). In the Spring
Creek watershed, samples from Buffalo Run, Slab Cabin Run, and Cedar Run had
numbers of microplastics well above the median value and samples from the mainstem
of Spring Creek had large numbers of microplastics, ranking 51 among the 53 statewide
samples.
Clearly, we have moderately high concentrations of microplastics in our surface
waters. Should we be concerned? There is evidence that microplastics have negative
effects on aquatic animals and studies with mice demonstrated enflamed intestines and
reduced sperm count (Lim 2021). However, negative effects of microplastics on
humans have not been documented. Scientists suggest that potentially negative effects
on humans could result from exposure to toxic chemicals associated with microplastics.
Major sources of microplastics to surface waters are urban and agricultural
runoff. The good news is several local conservation groups and government
organizations are continually working to reduce runoff in the Spring Creek watershed.
In addition to reducing runoff, we all can reduce our reliance on single-use plastics and
purchase products that are not made with plastic. Savitz (2021) suggests we
encourage our legislators to support public policies aimed at reducing use of plastics.