Priorities for Protecting against Emerging Chemical Pollutants 21
Photo: Lloyd DeGrane
Impacts on Lake Michigan Waters Based on the rankings from the prioritization method described above, and the monitoring efforts undertaken by municipalities in the southern Lake Michigan area, we can examine how Lake Michigan has been affected by emerging contaminants. This section of the report examines the priority compounds detected in southern Lake Michigan and the drinking water that comes from it. Compounds detected in the source water by local water utilities (MWW, CLCJAWA) in 2011 are: progesterone, cis-testosterone, atenolol, perfluorooctane sulfonate (PFOS), cotinine, DEET, diltiazem, meprobamate, and sulfamethoxazole. In finished water, DEET, PFOS, atenolol, cotinine and sulfamethoxazole were detected. All except PFOS were evaluated by the ranking system and scored below chemicals ranked in the top 20. PFOS, along with several other perfluorinated surfactants, is listed in the UCMR 3 for monitoring by water utilities for potential regulatory action. Chicago’s Department of Water Management does not analyze for emerging contaminants routinely, but conducted a two-year study of emerging contaminants in Lake Michigan source water and finished water at the city’s treatment plants. Most of the compounds detected in source water were also detected in finished water, evidence that removal of these chemicals through conventional treatment is not sufficient. The data from water analysis showed that the following compounds were detected in both: 2,4-D, atenolol, atrazine and atrazine transformation products, BPA, caffeine, cotinine, cyanazine, dehydronifedipine, furosemide, gemfibrozil, iopromide, meprobamate, DEET, nicotine, PFOS, phenytoin, progesterone, simazine, theobromine, and Tri(2-butoxyethyl) phosphate (TBEP). Of the compounds on the priority lists, BPA, gemfibrozil and TBEP were detected in Chicago’s source water, and TBEP was detected in finished drinking water. A study by the MMSD and the USGS in the Milwaukee Metropolitan Sewerage District service area analyzed water in the Milwaukee River watershed and Milwaukee Harbor and reported the occurrence of 80 different compounds in the streams and harbor. Of those on the stream-source water priority list, Tris (dichloroisopropyl) phosphate (Fyrol FR 2), TBEP, HHCB and AHTN were detected. The fact that many more compounds were detected in the Chicago Department of Water Management study and the MMSD/USGS Milwaukee study could be attributed to the fact that many more samples were collected and analyzed than in the annual monitoring done by Milwaukee Water Works (MWW) and Central Lake County Joint Action Water Agency (CLCJAWA). Many of the priority-ranked compounds weren’t even tested for in the Chicago Department of Water Management study, the MMSD/USGS Milwaukee study, or by the CLCJAWA.