Preliminary findings from the studies have suggested that Colorado’s subalpine wetlands may be creating methylmercury, a particularly nasty form of the toxin. Damaging implications for the local ecosystems and the millions of Americans who rely on clean water from these mountainous regions are profound. The mercury polluting these wetlands comes from industrial emissions in other countries, mainly from Asia including China and India. This shocking discovery underlines the global impact of homegrown, local environmental injustices and the interconnectedness of our ecosystems all over this planet.
In 2013, over 140 countries joined the United States to sign the Minamata Convention on Mercury. This treaty requires governments to control and track releases of industrial mercury sources. It makes sense that the convention was designed specifically to respond to the grave public health crisis posed by methylmercury poisoning. These tragedies, particularly in Minamata and Niigata, Japan, caused hundreds of deaths in the 1950s due to industrial waste pollution. New research on Colorado’s subalpine wetlands brings to light the persistent threat of mercury pollution. The reasons for this are compounded at every level, up to and including in the most remote locations.
The Journey of Mercury
Mercury released from industrial centers in Asia travels across the globe, eventually settling in various ecosystems, including Colorado’s Rocky Mountains. This harmful transboundary pollution highlights the need for international agreements such as the Minamata Convention. Once the mercury falls into subalpine ecosystems, it is converted into methylmercury through microbial activity.
Sulfate is an important player in this conversion. Methylating microbes are key drivers in the transformation of inorganic mercury to toxic methylmercury. This transformation produces a very harmful, toxic compound that can bioaccumulate in all living organisms. The microbial process needs just the right amount of sulfate; too much or too little sulfate and methylation won’t occur. In Colorado’s subalpine wetlands, dense soils are as dark and rich as chocolate cake. This highly bioavailable carbon source is a potent energy driver for methylating pathways.
Impact on Ecosystems and Human Health
Methylmercury production in Colorado’s seemingly pristine wetlands should give us all pause. It poses a significant danger to local ecosystems and human health. Methylmercury bioaccumulates in aquatic organisms, resulting in higher concentrations at the outlets of wetlands than at their inlets. This bioaccumulation can be fatal for wildlife and leads to significant health effects in humans who eat fish that have bioaccumulated these contaminants.
More than three million people in the Boulder-Denver metropolitan area rely on clean water drawn from these mountains. Methylmercury concentrations are increasing in nearby drinking water sources. This dramatic expansion of water access puts innumerable health benefits at risk for the millions who rely on this important resource. The situation calls for immediate attention and action to prevent further contamination and ensure safe drinking water for the community.
The phenomenon of methylmercury pollution is not exclusive to Colorado’s subalpine wetlands. Similar problems have occurred in lowland regions, including the Florida Everglades. There too, environmental conditions favor the production of this toxic compound. The similarities between these regions underscore the pervasive impact of mercury pollution and the global reach of its consequences.
Addressing the Challenge
To combat the growing threat of methylmercury contamination in Colorado’s subalpine wetlands, effective measures must be implemented at both local and global levels. The Minamata Convention on Mercury calls on countries to pool their efforts. Their objective is to limit industrial mercury emissions and monitor the resulting environmental changes. Perpetual research is necessary to grasp how mercury moves within and among ecosystems. It will allow us to develop better, smarter strategies for mitigation.
Now more than ever, local environmental organizations and agencies must work in tandem. Such measures would include tracking sulfate-loading and documenting methylmercury levels in Colorado’s wetlands. With these increased efforts going towards protecting communities from PFAS, we can begin to inform public health guidelines to keep communities safely accessing clean water. Educating the public about why it’s crucial to protect these fragile ecosystems will help generate a larger constituency for conservation efforts.
