by Emil Morhardt
Here’s a follow-on to our August 21 post on plastic pollution in the Pacific Ocean. I know that this is unrelated to climate change, but the Climate Vulture is also interested in other environmental issues. Eriksen et al. (all associated with 5 Gyres Institute in Los Angeles in addition, in some cases, to their day jobs), are intent on tracking plastic pollution globally. This paper looks at the American Great Lakes, and consisted of a survey cruise across lakes Erie, Huron, and Superior in July 2012, towing a net for an hour at each of 21 sites. All but one sample were contaminated with micro-plastic debris, but with more than 90% of the plastic collected in Lake Erie off Buffalo and Cleveland. The average abundance was over 43,000 plastic particles per square kilometer (the densest samples had ten times this much), plus a lot of coal and fly ash particles, presumably from the many coal-fired power plants surrounding the lakes. Much of the debris consisted of multi-colored spherical micro-beads on the order of a third of a millimeter in diameter. Many of the potential sources such as sandblasting media were ruled out because they wouldn’t be multi-colored, and are heavy enough to sink so they wouldn’t have been captured in the net trawls in the first place. The best candidates seem to be facial cleansers and other consumer products (one clue is that the beads are multi-colored). Maybe it’s time to rethink what kind of non-biodegradable stuff manufacturers ought to be putting into our consumer products. We tend to think of the products as benign, but when we wash them down the drain they survive the wastewater treatment plants, so maybe they are not so benign after all. What do you think? Would you preferentially purchase biodegradable products?
Eriksen, M., Mason, S., Wilson, S., Box, C., Zellers, A., Edwards, W. J., Farley, H., Amato, S., 2013. Microplastic pollution in the surface waters of the Laurentian Great Lakes. Marine pollution bulletin 77, 177-182. Full paper at: bit.ly/1vGgr34