Conclusions

Mercury provides a case study for chemical integrity. Much is known about mercury's toxic effects, at higher doses, and there is a growing body of knowledge concerning effects at lower doses. At sufficient levels of accumulation of methyl mercury compounds, toxic effects occur, including neurotoxicity (brain and nerve tissue damage) and nephrotoxicity (kidney damage).

The Commission recognizes that both governments are currently considering proposals for further reductions in mercury emissions. The Commission encourages both governments to adopt and implement initiatives that will further reduce the release of mercury to the environment, including atmospheric emissions.

The effects of past mercury emissions, compounded by continuing emissions, will remain an issue for decades to come. Associated risks must be effectively communicated. While both governments have compiled and disseminated fish advisories, difficulties remain in reaching those most at risk and in effecting changes in behavior that would reduce that risk.

Significant gaps in knowledge remain about the processes by which mercury moves from source to water body, to fish and wildlife, to humans, and about the effects of low doses of mercury on human health. Scientists continue to explore plausible connections and build on the knowledge base. In addition to general studies of this nature, specific focused studies on mercury deposition and its effects on the Great Lakes are required.