Adam Wilson, M1, Class of 2026
How can a fish teach medicine, how does diabetes result from environmental contamination, and how does environmental contamination cause illness through biological and non-biological mechanisms? I recently read “The River Is in Us: Fighting Toxics in a Mohawk Community” by Elizabeth Hoover, which prompted these questions. Hoover describes the impact of contamination and disruption of a Native American community’s environment located at Akwesasne along the St. Lawrence Seaway and bisected by the U.S.-Canada border. Akwesasne is downwind and downriver from a few sites, such as Reynolds Metals and General Motors Central Foundry, recognized as particularly hazardous to human and environmental health by federal and state governments. As a foreword, the Mohawk community at Akwesasne has a long history that this article cannot do justice to. I highly recommend reading Hoover’s book for more information on historical and cultural contexts.
In the 1950s, the Great Lakes were connected to the Atlantic Ocean for ships by widening and deepening the St. Lawrence River. Additionally, a large number of locks, channels, and dams were constructed. Spawning grounds for fish were destroyed and the islands and land of Akwesasne were covered with dredged clay, harming agriculture, which has historically been a major part of Mohawk life. Furthermore, altering the St. Lawrence River led to lamprey spread upriver and facilitated the growth of parasite populations. Fishermen recall black spots, tumorous growths, and chunks missing from fish, worrying the community about the safety of consuming fish, which comprised the major protein in their diet. Akwesasne residents were compelled to consume less produce grown in their farms and gardens and less fish from their river due to the alteration of the St. Lawrence River.
Damming the river attracted industry, such as Reynolds Metals, the second-largest producer of aluminum in the world in the 1950s. General Motors soon followed to be close to a major supplier of aluminum for their products. In the early 1960s, trees downwind of Reynolds Metals began to brown, and farmers on Cornwall Island (the large red island on the map) noticed that their dairy cows had developed swelling in their legs, became lame, were losing teeth, and would crawl between patches of grass to eat. The lifespan of these cows went from eleven years to six years after Reynolds Metals began operating. In the late 1960s, the Ontario Ministry of the Environment identified that fluoride emissions from Reynolds Metals were responsible for the changes seen in the trees and dairy cows. Reynolds Metals was forced to install emission control equipment, though the urine samples of cows still showed high fluoride levels and the dairy industry of Akwesasne collapsed. Memories of cows starving and bleeding from their mouths continue to affect the community’s perception of the safety of their gardens, farms, and fish.
In response to the fluorosis incidents, in 1976, the New York State Department of Health advised a reduction in the consumption of fish in the area, and for women and children to avoid fish entirely. A similar advisory was posted by the Canadian ministry in 1978 after mercury, pesticides, and polychlorinated biphenyls (PCBs) were detected in fish. Concerned for fluoride levels in people, the Mt. Sinai School of Medicine conducted a study that concluded that there was minimal concern of fluoride toxicity in people. However, the study detected trace PCBs in fat samples, which led Mt. Sinai researchers to uncover a positive relationship between fish consumption and PCB blood levels. Again, advisories were put out recommending a further reduction in fish consumption.
PCB-laden hydraulic fluids had been used in the operation of the General Motors foundry, which were dumped in reclamation lagoons behind the plant. The lagoons overflowed several times and leached into groundwater, which made its way into the river. PCBs were designated a hazardous substance by the Clean Water Act in 1978 and were banned by the Toxic Substances Control Act due to their links to nervous system delays, cancers, decreased thyroid and liver function, and autoimmune disorders. In 1983, the New York State Department of Health announced that PCBs and other toxins were found in the groundwater near the foundry and recommended hazard reduction.
During this time, a midwife named Katsi Cook became increasingly concerned about the number of miscarriages happening at Akwesasne. Studies of breast milk were undertaken in 1984, which concluded that breast milk PCB levels were similar to levels in unexposed areas and that breast milk PCB levels increased with fish consumption. Though, the consensus was still that groundwater was the primary pathway by which PCBs found their way into human bodies. Community members attribute their low breast milk PCB levels to two decades of fish advisories and community concerns about the safety of their food and describe how their levels would be unsafe had they eaten more fish from the river. Concurrently with these breast milk studies, levels of PCBs in animals were examined. Animal studies found the following in livers and brains: a snapping turtle with 3,067ppm, sturgeon with 11ppm, a shrew with 11,520ppm, an owl with 2,290ppm, and a duck with 190ppm. For context, a chicken with more than 3ppm was considered unfit for human consumption, and above 50ppm was considered toxic waste. Reflecting on the extremely high levels of PCBs in ducklings, a wildlife epidemiologist remarked that Akwesasne was “the worst place in the world to be a duck,” resonating with how some Akwesasne residents felt about their homes, rivers, foods, and bodies.
In 1987, GM capped its industrial landfill and paid for the remediation of lands that had demonstrated unsafe PCB levels in accordance with its status as a Superfund site. Remediation continued for a couple decades, until 2008, when the financial crisis caused GM to go bankrupt. Bankruptcy freed GM of responsibility for rehabilitating dozens of toxic waste sites across thirteen states. The damage of PCB contamination had already been done, though. Elevated PCB levels among Mohawk adults were found to be correlated with higher prevalence of autoimmune disease, thyroid problems, hormonal changes, diabetes, cognitive deficits, and cardiovascular disease.
Contaminated fish represent the multifactorial etiology of disease and teach me that assigning singular causes to disease may miss key contributors. For example, the age-adjusted prevalence of diabetes in the Mohawk population is two times the national U.S. average and is due to multiple factors. Diabetes, as I understand it from my lectures, is usually due to a loss of sensitivity to insulin or a loss of insulin production. In the Akwesasne population, a loss of insulin sensitivity is the primary driver of diabetes. It is remarkably easy to wave a hand at the issue of diabetes and say, “Well, they don’t exercise enough and do not eat well.” However, this explanation denies other contributing factors and causes that led to diabetes. In the case of Akwesasne, altering the St. Lawrence River led to a decrease in fish consumption and produce consumption, fluorosis led to economic instability in the collapse of the dairy industry and less produce and fish consumption due to concerns about their safety, and PCB levels continued to decrease produce and fish consumption again due to concerns of their safety. What resulted is the replacement of fresh food for fast food and outdoor activities like fishing and gardening for more sedentary activities.
Recognition of these key contributors is important to design interventions upstream of an illness event. For instance, instead of intervening only at the level of providing medication to diabetic patients, public health efforts aimed at restoring safe levels of PCBs in fish and reassuring the safety of gardens would allow Akwesasne residents to eat healthier food sources as residents had in the past, before lamprey took holes out of fish, before cows lost their teeth, and before dead fish washed up on their shores due to PCB toxicity.