Chemical Contaminants

Chemicals are essential to everyday life and human survival, but the word “chemical” carries some negative connotations outside the realm of science.


Chemicals have a widespread association with herbicides, pesticides, pharmaceuticals, and other chemical-based products. These products are often associated with environmental degradation and sometimes have unfavorable effects on human health. As a result, we have a social aversion, or defensive response, to the word “chemical.”

It is essential to understand that we encounter chemicals at every moment of every day and that some can provide beneficial services. It is vital to sift through the nuances of chemical contamination, such as which chemicals are harmful, at what volume are they harmful, and how long one can be directly exposed to a chemical before it causes adverse health effects.

When we test for contamination in water, we are testing for “harmful concentrations” of a chemical; not the entire compound.


The word “inorganic” does not imply a chemical compound is synthetic, or human-made. Most of the Earth is inorganic!

Inorganic compounds are naturally existing compounds, which can be found in Earth’s water and rock layers. We refer to these compounds as inorganic simply because they do not contain elements found in living organisms (e.g. carbon and hydrogen).

One of the most commonly occurring inorganic compounds sodium chloride, or table salt, is mined from beneath the Earth’s surface and used in everyday cooking.

Most water supplies will contain trace amounts of inorganic compounds. However, inorganic compounds can have adverse effects on human health when more than the recommended dietary amount of groundwater.

Adverse health effects of overconsumption may affect the liver, kidney, nervous system, circulatory system, blood, gastrointestinal system, bones, or skin depending upon the inorganic compound and level of exposure. Elevated amounts of inorganic compounds can result in hazardous drinking water contamination.


Native copper is one of only a few metallic elements that can exist in its pure, elementary form. The Keweenaw Peninsula, located in Michigan’s Upper Peninsula, is home to the largest concentration of native copper deposits in the world!


Chemicals Emerging Interest Emerging Issues
Arsenic (As)
Chemical Element
Private well users are most vulnerable to arsenic contamination because their source water is groundwater, thus are susceptible to the mobilization of geochemical arsenic. Researchers must study the source of the arsenic and mechanism through which it is released into groundwater to protect private well users. Human-made changes to local hydrography help dissolve arsenic into groundwater, which is then pumped for drinking water. The resulting arsenic levels in the water system can prove poisonous to humans.
Copper (Cu)
Chemical Element
There has been a rising interest in medical literature in the connection between inorganic copper consumption and cognitive disease and deficits. In scientific investigations of copper intoxication in humans, studies have indicated that copper imbalances in the brain are directly and indirectly related to the development of Parkinson's disease, Alzheimer's disease, aceruloplasminemia, Menkes disease, amyotrophic lateral sclerosis, Huntington disease, occipital horn syndrome, and Prion disease. Currently, experimental results from chronic copper exposure with rats indicate more research needs to be done to accurately identify safe copper levelers for human consumption in drinking water. There has been a longstanding concern with corrosive water and elevated copper exposure in home plumbing systems. A common indicator of corrosive water is the identification of blue-green stains at copper piping joints or the mouth of a faucet.
Fluoride (F-)
Inorganic Compound
There is a growing body of scientific literature that suggests fluoride intake may be associated with adverse health effects. Prolonged and high exposure of fluoride has been reportedly associated with complications with the thyroid, developing brain, osteosarcoma, and other bone conditions, such as skeletal fluorosis. Fluoride has been intentionally added to many sources of drinking water due to the positive relationship between fluoride and the prevention of tooth decay. However, many think that the practice of intentional fluoridation of public utilities has minimal benefit, especially considering emerging health risks associated with high fluoride intake.
Lead (Pb)
Chemical Element
Since the investigation into the cause of the Flint water crisis, corroded lead service lines are suspected to be a primary factor in lead drinking water contamination. As a result, the EPA is considering the effectiveness and plausibility of a national lead service line replacement program. When lead-contaminated water is consumed, the lead in the water enters one’s bloodstream and causes an elevated blood lead level, which can result in lead poisoning. Since lead is a neurotoxin, can have a detrimental effect on the many developmental processes, such as behavior, intelligence, and overall life achievement.
Radon (Rn)
Chemical Element
Generally, Radon solely affects private wells because public drinking water systems aerate water during treatment processes and dissolved Radon is released into the atmosphere. Currently, due to the debate surrounding the establishment of Radon, measurement methods in drinking water and health parameters, the EPA has yet to establish a Maximum Contaminant Level for Radon. Mitigating Radon in public and private groundwater supplies differ due to their respective distribution network. Since public water supplies are aerated during treatment, the reintroduction of radon into drinking water is unlikely. On the contrary, private groundwater supplies harnessed for private wells are more vulnerable to radon because water is only treated for radon at the point of entry (where the water supply enters the home from the well), if at all.
Salt (NaCl)
Inorganic Compound
Currently, the Safe Water Drinking Act has yet to establish a maximum contamination level for sodium chloride (Salt). In 1998, the EPA published the first edition of its Drinking Water Contaminant Candidate List, for which maximum contaminant levels are to be established, and Sodium was named as a drinking water contaminant. However, in subsequent editions (2005, 2009, 2016) Sodium was left off the list entirely due to the assumption that the majority of human salt consumption came from food. While healthy amounts of sodium and chloride naturally occur in drinking water, sources such as road salt, industrial wastes, sewage, fertilizers, water softeners, and proximity to saltwater can usually cause a salt spike in drinking water supplies. Although salt exposure is not a matter of concern for every person, it can be quite dangerous for folks on low-sodium diets, especially those with certain heart conditions, circulatory or kidney diseases, or cirrhosis.
Selenium (Se)
Chemical Element
Selenium plays an important role in the brain as an antioxidant. This said, long-term exposures to high levels of inorganic selenium, have been widely cited as a factor in the development of neurological disease. A few long-term studies have attempted to establish a connection between the prolonged consumption of inorganic selenium in drinking water and ALS. Based on epidemiologic data, these studies have concluded that long-term exposure to trace amounts of selenium may have a toxic effect on motor neurons, therefore contributing to the development of ALS. However, since the pathogenesis of ALS remains a subject of scientific debate, environmental and lifestyle factors of disease development remain controversial. As the case with salt, selenium is integrated into our everyday diets. As a result, it is difficult to differentiate between the sources of a selenium imbalance. Toxic concentrations of selenium are generally released into the environment through poor drainage practices in industrial smelting at iron mines. Tailings basins and waste rock storage piles are necessary components of iron mining operations. When drainage practices are irresponsibly managed, unexpected storm waters and snowmelt waters can remove naturally occurring substances, including selenium, from tailings basins and waste rock piles, and transport the dissolved materials to surface drains and groundwater.
Nitrate (NO3-)
(Inorganic Nitrate)Inorganic Compound
In the realm of public health, nitrates in drinking water, particularly in water used in baby formula, has long been associated with nitrate poisoning and blue baby syndrome. Crop farms and livestock operations contribute significantly to nitrate contamination through waste and fertilization runoff unintentionally introduced into the waterways. In addition to nitrogen contamination by agriculture, nitrates can leach into groundwater from improperly regulated septic systems and wastewater networks. Nitrogen runoff is a significant facilitator of algal blooms.
Additionally, nitrogen provides a nutrient-rich environment for toxic bacteria to prosper, such as cyanobacteria blooms. In the past, cyanobacteria blooms were thought to be caused solely by phosphorous, thus could be treated with aluminum sulfate. However, aluminum sulfate cannot be used to treat nitrogen. As a result, nitrogen runoff and the leaching of old septic systems must be contained to protect source water from cyanotoxins.