Water Contaminants—What We Don’t Know Can Hurt Us

We generally assume that the water coming out of our tap is safe to drink. There are systems in place to monitor and control the quality of drinking water. But do those systems always work?

The obvious answer is no. One look at Flint, MI, tells us that water contaminants can make their way into our home faucets. Lead is but one of the potential substances that can cause our drinking water to be unsafe.

There are multiple sources and types of tap water contaminants, each presenting a level of hazard. Some will sound familiar; others may be new to you. We could all stand to be more aware of water toxins and how to keep them from affecting our health and the health of our families.

Agricultural Pollution

Areas with a large agricultural presence are subject to pollution from farm runoff. Pesticides, bacteria from animal waste, and nitrate are all hazards of agricultural contamination.

Agricultural pesticides have been linked to cancer, bacteria can cause gastrointestinal and other illnesses, and nitrate can cause low oxygen and low birth weight in babies.

Industrial Pollution

In 2015, industries in the United States dumped 191 million pounds of chemicals into our waterways. Some of that is illegal dumping, but a lot of it is not—despite knowing that some of these chemicals make it to our faucets, our politicians have not seen fit to regulate them.

Since that report, environmental regulations have not improved. Rather, they have been rolled back, making our water less likely to be free of chemical contamination.

Industrial pollution leaves behind lead, chromium, arsenic, mercury, cyanide, copper, and more. They all have adverse effects on human health including links to cancer, reproductive problems, low birth weight, and heart disease.


Ew! We know this is a gross one. Most of this type of pollution is removed during wastewater treatment in the United States, but those facilities can break down or be overwhelmed.

Sewage that makes its way into drinking water can cause infections from E.coli, shigella, salmonella, and other bacteria, to viruses like Hepatitis A.


Wastewater is simply water that has been used. It’s found everywhere and carries chemicals from roadways and yards, water that goes down the sewer when we wash our cars—it’s all wastewater.

Again, this water is usually treated in the United States before becoming drinking water, but some of the contamination contained in wastewater is not removed by traditional wastewater treatment. Flame retardants, prescription medicines, personal care product chemicals, and more can make their way into the water we drink.

It’s more difficult to pin down how wastewater harms us because it’s a broad category and can include many different types of contaminants. But all of the chemicals, bacteria, and other contaminants from agricultural, industrial, and sewage pollution are potentially in wastewater as well.

Forever Chemicals

PFAS chemicals, sometimes known as forever chemicals, are a large group of substances that came into being in the 1930s. The first commercial use was Teflon coatings for cookware but they are now used in a wide range of consumer products. These 5,000+ chemicals do not break down in the environment and have found their way into our drinking water.

The most common PFAS chemicals have been linked to cancer and low birth weight.

Switching to Bottled Water

We’re trained by a lot of good advertising to think that bottled water is the natural alternative to tap water. But be careful. Bottled water isn’t regulated even to the degree of tap water, and some of it really is just plain tap water.

If you want to remove contaminants from your drinking water, a high-quality water filter is a better choice. It’s less expensive over time and doesn’t create the mountains of plastic pollution for which the bottled water industry is responsible.

Before you buy, do your homework! You’ll want to check out the NSF standards for water filters and choose one that fits your needs and concerns.

How Did We Get Here?

Believe it or not, pollution used to be far worse. There were few if any environmental regulations and people and companies polluted at will. It was during the Nixon administration that modern environmental stewardship was born.

The Clean Air Act was passed in 1970, and with it, the Environmental Protection Agency (EPA) was born. Two years later came the Clean Water Act, which was amended from a set of 1948 regulations. Together, they bore environmental fruit and we began seeing less smog and fewer dead fish.

We were meant to start with those regulations and move forward. As new pollutants arose, new regulations would continue our progress toward clean air and water. What failed us was the nature of compromise built into our political system.

When crafting new regulations, politicians considered input from industry as well as environmental scientists and the public. Lobbyists for industry spent a lot of money trying to persuade legislators not to impose standards or regulations.  

We ended up with our air and water mired in the same system that gave us the tax code. Fragmented, difficult to interpret, and nearly impossible to enforce rules and regulations that tried to please everyone and in the end failed to protect our drinking water.

In recent years we have seen the EPA actively rolling back standards on pollutants like mercury, a heavy metal that harms the central nervous system. Eroding commitment to including public comments and protecting public health has left us with a system badly in need of an overhaul.

What Comes Next?

There are multitudes of known contaminants in water supplies all over the United States, many of them unregulated. One of the best ways to change that is by making your voice heard through organizations like Moms Clean Air Force or the Environmental Defense Fund. Our voices matter.

In your own home, consider installing a high-quality water filter to give you peace of mind and improve the quality of the water you drink. Political change takes time, but a water filter may be able to give you clean water while we work towards better regulation.