A study released by Minnesota officials reveal that of 50 randomly-selected lakes, only three of them were free of the 125 chemicals scientists ran tests for.
Among those leading the pack was DEET, the common insect repellent, which tested positive 76 percent of the time.
Despite its every-day role in the life of many Americans, DEET can cause “serious and devastating complications” when large poisonings occur, including disorientation, clumsiness when walking, seizures and coma, according to Medline Plus.
The medical site further warns that DEET is especially dangerous in the case of small children who can experience seizures when exposed to high amounts of the chemical for extended periods of time and should never be used on infants.
In addition, scientists found a number of endocrine disrupting compounds, which, according to the National Institute of Environmental Health Services, are chemicals believed to interfere with the body’s endocrine system to produce adverse developmental, reproductive, neurological and immune effects both in humans and the wildlife.
For example, Bisphenol A, a chemical used in plastics and linked to abnormal heart rhythms and lower thyroid hormone levels in newborn boys, appeared in 40 percent of the lakes.
Other chemicals scientists identified in their search included carbamazepine, a medication used to treat ADHD; SSRI antidepressant medications; artificial sweeteners; caffeine and benzotriazole, which is used as a corrosion inhibitor in aircraft de-icers as well as antifreeze, hydraulic fluids and silver protection in dishwater detergents.
Furthermore, while scientists did not originally plant to test for it, evidence of cocaine was detected in one third of the sampled lakes.
While some of the chemicals listed have known biological affects, such as SSRIs in regards to fish behavior and freshwater mussel reproduction, it's unclear what others, such as carbamazepine, will do.
Ultimately, according to the study, the results confirm the types of investigations over the past decade that have shown evidence of the presence of pharmaceuticals, personal care products and other unregulated chemicals in surface water across the state. And while the effects of all are not clear, as the study states, “a growing body of evidence suggests that some unregulated contaminants may be exerting adverse effects on aquatic ecosystems in subtle but still undocumented ways.”