Mercury is a neurotoxin that can accumulate in the tissues of living organisms, such as fish, that live in an environment high in mercury. One of the main concerns surrounding mercury poisoning is that pregnant women who eat fish can pass mercury on to their unborn children, who are very sensitive to its effects. The state of Minnesota has been one of the leaders in identifying and acting on this health threat. In 1988, Hennepin County implemented a Mercury Management Plan (MMP) designed to prevent mercury from unnecessarily entering the waste stream.
MMP focuses mainly on preventing mercury, in the form of emissions, from entering the environment. This is accomplished through state-of-the-art emissions control technology that was installed in 1994 at the Hennepin Energy Recovery Center, the county's waste-to-energy plant. Additionally, mercury-bearing items such as batteries, thermostats, switches, and fluorescent and high-intensity discharge lamps, are collected year-round. Drop-off is free for residents and there are enough drop-off locations to encourage widespread participation.
MMP's success derives from public awareness and opportunities for collection. The county aggressively promotes MMP: between 1993 and 1994 over 50,000 flyers were mailed to businesses, information packets were sent to 4,000 licensed hazardous waste generators. And, on an annual basis, approximately 3,000 more businesses are targeted.
As a result of MMP's efforts, mercury emissions in the county fell over 90 percent between 1989 and 1995. Because Hennepin County's mercury levels were within permitted levels when the program began, the MMP symbolizes a pioneering effort in stressing the need for further reduction. The unexpected result of this leading example was its incorporation into state policy and statute. Other indirect benefits are those such as the tightening of Minnesota State mercury emissions standards, which were solely based on the low levels achieved by Hennepin County.