You don't have to live in Flint, Michigan, to worry about your family's water supply. Concern about Flint's continuing battle with lead contamination has people across the country paying closer attention to what is flowing out of their taps.
A Harvard study published in August warned that tap water in 33 states has industrial chemical levels that exceed the minimum standards set by the Environmental Protection Agency, which has monitored the nation's water since passage of the Safe Water Drinking Act in 1974.
An investigation by The Associated Press found traces of prescription drugs in water supplies that serve 46 million Americans, and a new study out of the United Kingdom calls such contamination there "widespread" and "routine."
Nitrates leaching into water in rural areas are a danger to pregnant and nursing women and their babies.
And people protesting the Dakota Access Pipeline fear its construction could poison the water supply of Native Americans in North Dakota and South Dakota.
For all the myriad concerns, it's two chemicals — hydrofluorosilicic acid and lead — that are most in the news right now, and both have ties to Michigan.
There are also three simple ways to make your drinking water safer. Here's what every family should know.
The fuss over fluoride
Grand Rapids, Michigan, was the first city in the world to fluoridate its water supply, in an experiment begun in 1954. Within 11 years, tooth decay in children had dropped by 60 percent, according to the National Institute of Dental and Craniofacial Research, and the rush to fluoridate the nation was on.
Now, nearly three-quarters of Americans are connected to community water supplies treated with fluoride. But there are disparities. In Utah, one of the last states to add fluoride to water, the figure is just 51.7 percent, and in Idaho and Montana, it's even lower: 31.9 percent and 33.7 percent, respectively.
The practice was adopted after decades of research into what was causing permanent brown stains on children's teeth in Colorado at the start of the 20th century. The phenomenon, which came to be known as Colorado Brown Stain, was ultimately linked to regular exposure to highly fluoridated water while teeth are developing under the gums. But the investigation also revealed something else: The mottled teeth of the Colorado children appeared resistant to decay.
Researchers then looked for the sweet spot of fluoridation — the amount of fluoride that would protect against decay without leading to the discoloration of teeth, a condition that is tellingly called fluorosis.
This led to the Grand Rapids trial and a blooming acceptance of fluoride as an essential part of dental health despite isolated pockets of resistance. The 1964 movie "Dr. Strangelove" helped fuel the latter by suggesting that fluoridated water was a Communist plot: "Do you realize that fluoridation is the most monstrously conceived and dangerous plot we've ever had to face?" one character says.
In recent years, however, the drumbeat of dissent has edged closer to the mainstream, nudged by groups like the Fluoride Action Network and natural-health proponents like Dr. Joseph Marcola. Among other things, the anti-fluoride movement points out that the U.S. is alone in its widespread fluoridation. Only about 3 percent of Western Europeans drink water with added fluoride although many Europeans ingest fluoride that is added to salt and milk. Worldwide, the figure is about 5 percent, with Americans accounting for half, according to The Washington Post.
Moreover, the U.S. Department of Health and Human Services last year lowered the amount of fluoride it recommends, this coming on the heels of a 2014 report showing that 41 percent of American children between the ages of 12 and 15 have varying degrees of fluorosis.
While fluoride has been shown to prevent tooth decay, it works when it's applied to the teeth, not swallowed, which is one reason the water department in Kennebunkport, Maine, was one of the leading proponents of ending fluoridation there.
The measure passed, 13,385 to 6,918, but not without complaints from some local dentists, one of whom said the vote pushes children's dental health back to the 19th century.
Getting the lead out
Despite the ongoing fuss over fluoride, it's the presence of lead in drinking water that is the most urgent concern in most communities. The revelation that children of Flint were being slowly poisoned by water with dangerously high levels of lead, iron and bacteria has prompted municipalities across the country to examine their water supplies and delivery systems.
Flint's crisis was the result of a catastrophe of errors: the decision to draw water from the polluted Flint River instead of Lake Huron; the failure of the city to treat the water in accordance with federal law; and the slow response to citizen complaints about discolored water.
The Flint River in Flint, Mich. | Carlos Osorio, Associated Press
It wasn't until a local pediatrician found that lead levels in toddlers were doubling and tripling that the city acknowledged the problem. By then, the river water was corroding the water mains and pipes, causing even more lead to seep into the supply.
But most water that contains too much lead became contaminated simply because it travels through old pipes, whether under city streets or in your home.
"Lead found in tap water usually comes from the corrosion of older fixtures or from the solder that connects pipes. When water sits in leaded pipes for several hours, lead can leach into the water supply," the Centers for Disease Control and Prevention says.
According to the EPA, the ingestion of lead can damage the brain, kidneys, nervous system and blood cells. The risk is greatest for young children and pregnant women.
An investigation by USA Today found excessive lead in 2,000 water systems across 50 states, and many of the systems served schools and day cares.
In Massachusetts, investigators tested water at 300 public schools this year and found that more than half had at least one sample with high levels, leading some schools to shut off drinking fountains and taps this month, according to The Boston Globe.
The Northeast and South have the greatest risk of lead contamination, according to an analysis conducted by Vox.
In its report, Vox said the risk is greatest in America's oldest and biggest cities, such as New York and Chicago.
Although it's difficult to compare risk levels because each state has its own standards for testing, western states such as Nevada, Arizona and Utah have some of the lowest risks, the Vox report said.
Summit County, Utah, for example, had a lead risk of 1, on a scale in which 10 was the highest. Salt Lake County's risk was 4.
Municipalities are required to file annual reports on the safety of their water. They're called Consumer Confidence Reports, and some are available online. If your water comes from a private well, it's up to you to monitor its quality.
Regardless of what you find out, there are two easy ways to cut down on any potential lead exposure for your family, according to the EPA. First, let the water run briefly before filling your glass or pot.
"The more time water has been sitting in your home's pipes, the more lead it may contain. Anytime the water in a particular faucet has not been used for six hours or longer, flush your cold-water pipes by running the water until it becomes as cold as it will get. This could take as little as 5-30 seconds if there has been recent heavy water use such as showering or toilet flushing. Otherwise, it could take two minutes or longer," the EPA advises.
Second, use the coldest possible water for drinking, cooking and making baby formula. Hot water has higher concentrations of lead. You don't have to worry about bathing — lead doesn't enter through the skin, but don't open your mouth in the shower.
The EPA also advises people to get their home water tested, particularly if your home was built before 1986, when stricter rules about pipes were implemented. Although municipalities file water safety reports, these don't necessarily reflect the quality of the water coming out of your tap, since old pipes in your house could be the cause of contamination.
If you're on public water, first contact your local water department because some may provide testing for you. Otherwise, send a sample to a company that provides testing for a fee, or buy a do-it-yourself kit, although investigative reporter Alison Young of USA Today found that a difficult task.
Unlike when filling a glass for drinking, when collecting water for testing, you should take a sample when water has been sitting in the pipes for six hours or more. If lead or other contaminants turn out to be present, you may need to install a filtering system, or, in the worst-case scenario, resort to bottled water. Or move.
The catastrophe in Flint notwithstanding, the CDC still assures people that America is among the countries with the safest drinking water overall in the world. In an infographic it released in 2014 on global water safety, the United States' drinking water was overall deemed safe, unlike much of Russia, Africa, Asia and South America.