Every few months, it seems, there is another Great Lakes crisis. We’ve seen toxic algae, invasive mussels, industrial and wastewater pollution, fertilizer runoff, Asian carp and lamprey eels.
Through it all, the lakes have somehow survived, though at a cost. Native species have been wiped out and the price of dealing with other fallout has run into the tens of millions.
Now there’s a new threat that’s just as scary as anything that has come so far but essentially invisibile: masses of tiny plastic particles, some so small they can only be seen through a microscope, found in Lakes Superior, Huron and Erie. Lakes Ontario and Michigan are being checked right now by scientists skimming the surface with fine mesh netting.
Experts say it’s unclear how long the “microplastic” pollution has been in the lakes or how it is affecting the environment. Studies are under way to determine whether fish are eating the particles, which may come from city wastewater, and passing them up the food chain to humans.
So far, scientists have discovered that the number of plastic specks in some samples from Lake Erie were higher than in comparable samples taken in the oceans.
They also know where many of the particles — perfectly round pellets — come from: they are abrasive “micro beads” used in personal care products such as facial and body washes and toothpaste too small to be captured by wastewater treatment plants and washed into the lakes.
Labs have detected two potentially harmful compounds in the Lake Erie plastic debris: PAHs, created during incineration of coal or oil products, and PCBs, which were used in electrical transformers and hydraulic systems before they were banned in 1979.
Both are capable of causing cancer and birth defects.
Michigan has a long history with PCBs. In the 1970s a Michigan chemical plant mistakenly added PBB (polybrominated biphenyl) — a toxic fire retardant related to PCB — to dairy cattle feed, and distributed it to farms across the state.
The concern is that the microplastic will make its way into fish and then into humans, bringing PAHs and PCBs into our bodies. No one knows what that could mean.
While a couple personal care product manufacturers have said they will phase out micros beads, that’s not universal. And the beads will continue to be washed into the lakes for years to come.
We have long treated the Great Lakes as giant sewers, and more and more they’re beginning to look like it. Sooner or later, that kind of recklessness is going to catch up with us — if it hasn’t already.