The state will install filters in more than 100 private wells east of the Twin Cities after research shows a contaminant found may pose a greater health risk than previously thought.
MPR reports recent research shows that the chemical compound trichloroethylene, or TCE, could harm the immune system, prompting the Minnesota Department of Health to revise its guidelines for recommended exposure.
Wells in Bayport, Baytown Township and West Lakeland Township were retrofitted with special filters if TCE levels were 5 micrograms per liter or above--the level associated with a potential cancer risk.
The new guideline recommends exposure levels below 0.4 micrograms per liter, MPR says, affecting about 115 of those wells. However, health officials say most people are unlikely to experience health impacts from exposure to TCE at levels up to five times the Health-based Value of 0.4 micrograms per liter.
TCE is a nonflammable, colorless liquid commonly used in the industrial field to degrease metal parts and is also used as a dry-cleaning agent, according to MDH. The contaminent dissolves in water and readily evaporates from soil and water into the air.
Officials believe the TCE in the west metro, first detected in 1987, came from a shop in Lake Elmo that no longer exists.
MPR reports the filters are 100 percent effective in removing TCF. The Minnesota Pollution Control Agency is expected to increase testing for TCE to two or three times a year.