In June 1969, Ohio's Cuyahoga River burst into flames. This fire, fueled by toxic pollutants and causing an inferno eight stories high, served as an effective message direct from Earth to its human inhabitants: Shape up. We should consider ourselves lucky that the planet didn't choose a more conspicuous sign, such as global combustion. The Cuyahoga fire was largely responsible for the establishment of the Safe Drinking Water Act in 1974.

Today, with more than 27 years of health research under our medical belts, it's time to see how standards for our municipal water stack up against the quality of our local water supply.

What's in the Water?
While some water contaminants come from natural sources, such as pathogens from wildlife and toxic minerals leached from ground minerals, more severe contaminants are largely a result of human activity. These include sewage, industrial waste, pesticide runoff, improper dumping and defective treatment. These contaminants fall into five categories: pathogens, metals and inorganic chemicals, synthetic organic chemicals, radioactive materials and additives.

Pathogens include protozoa, bacteria and viruses that are introduced into the water through sewage systems or animal waste runoff and cause a variety of intestinal disorders, especially affecting immune-impaired individuals. Pathogens have also been linked to higher rates of miscarriage.

It is estimated that cryptosporidium, the protozoan responsible for causing the gastrointestinal disease cryptosporidiosis, is present in more than 50 percent of treated water. In 1993, the town of Milwaukee, Wis., suffered an outbreak of this disease, caused by infected water. More than 400,000 people became ill, 4,000 were hospitalized and approximately 50 died.

Another example of a deadly water pathogen is Legionella pneumophila bacteria, the cause of Legionnaires' disease, which killed 34 people in Philadelphia in 1976 and six of 45 victims in Massachusetts, Rhode Island and Michigan in 1993. The source of contamination was the buildup of bacteria in cooling towers.

Metals and inorganic chemicals, with water serving as their conduit, can manifest in humans as reproductive dysfunction, kidney problems, cardiovascular disease, cancer, and fetal, neurological and brain damage.

Metals that contaminate many water systems across the country include lead, cadmium, mercury and arsenic. Plumbing—derived from the Latin word plumbum, meaning lead—is the primary source of lead contamination in water. Over half the cities in the United States still use lead or lead-lined pipes in municipal plumbing systems. Cadmium and mercury both come from industrial production and discharge. The risk of mercury exposure is derived mostly from fish, specifically swordfish, living in mercury-contaminated waters. This metal is bioaccumulative, meaning it becomes more concentrated as it moves up the food chain.

In May 2000, the US Environmental Protection Agency (EPA) changed the maximum contaminant level (MCL) for arsenic from 50 parts per billion (ppb) to 5 ppb, citing an "additional protection to at least 22.5 million Americans from cancer and other health problems." The original MCL of 50 ppb was based on a Public Health Service standard determined in 1942—a standard 59 years old. Some experts estimate 50 ppb may pose as much as a 1 in 50 risk of cancer.

Nonmetallic inorganics include asbestos, cyanide, and nitrates and nitrites. The carcinogen asbestos is quite prevalent throughout the country due to the presence of asbestos-cement in water mains. Cyanide enters the water system through insecticides and plastics manufacturing. Nitrates and nitrites stem from agricultural runoff, fertilizers, septic tanks and some industrial processing. Nitrate ingestion is the cause of oxygen deprivation in babies, called blue-baby syndrome.

Synthetic organic chemicals are also prevalent in modern industry, used in everything from pesticides to cosmetics to common plastics. Despite their pervasiveness, little or no research has been conducted to determine their health risks and, consequently, their safety rating in water. Based on a 1995 study conducted by the nonprofit Environmental Working Group, one glass of tap water in Fort Wayne, Ind., contained nine different pesticides.

Radioactive materials are both natural and man-made. The natural varieties posing the greatest concern include radium-226, radium-228, radon-222 and uranium, all of which are products of a certain type of geology. Different parts of the country are susceptible to varying types of radioactive materials. Man-made radioactive materials originated with the introduction of nuclear energy and are all carcinogenic. Nuclear facilities, active or inactive, and mining areas carry high risks for contaminating water with radioactive materials.

Additives, such as chlorine, are also included in drinking water. In 1974, it was discovered that when chlorine reacts with naturally occurring organic matter, a group of toxic byproducts called trihalomethanes (THMs) manifest, among them chloroform. THMs have been associated with rectal and bladder cancers, as well as birth defects.

Fluoride is another hotly disputed additive. A byproduct of aluminum, fluoride is said to prevent tooth decay. Some studies indicate, however, that fluoride is carcinogenic and its addition to municipal water is irrational and dangerous.

What is the Government Doing?
Based on the Safe Water Drinking Act, all community water systems must comply with a set of standards established by the EPA. These standards list maximum contaminant levels (MCLs) for 84 pollutants, as determined by a risk assessment. "The EPA generally sets MCLs at levels that will limit an individual's risk of cancer from that contaminant to between 1 in 10,000 and 1 in 100,000 over a lifetime," according to the EPA. "For non-cancer effects, the risk assessment estimates an exposure level below which no adverse effects are expected to occur."

There are a few problems with this system:

  • Are EPA standards strict enough? Many experts say no, believing the EPA allows too many contaminants in municipal water.
  • Many of the MCLs are based on estimates, such as how much water a person will drink in his or her lifetime.
  • Not all dangerous contaminants are included in the EPA's list.
  • If a water system is not meeting standards, the water company is given a time limit to comply. Meanwhile, we continue drinking, cooking with and bathing in unfit water.
  • Other environmental factors may contribute to a person's susceptibility to illness due to contaminated water.
  • Enforcement is poor. A 1995 study conducted by the Natural Resources Defense Council (NRDC) revealed 25,000 public water systems failed to meet standards; in other words, in that year 53 million Americans drank water that did not meet EPA standards or water that was not being treated effectively for lead, parasites and bacteria.

What Can I Do?
Find out what's in your water. Call your local water company and ask for the results of water testing from the last two years. If your local water company serves more than 10,000 people, it's required to send customers a yearly Consumer Confidence Report (CCR). You may also consider having your water tested by a private lab. This way, you can also determine what your house plumbing is contributing to your water supply.

Also, consider a filter. There are several different types of water filters, each designed to remove specific contaminants. The purification system most suited for your needs depends on what contaminants are already in your water. Make sure your filter is certified by NSF International (formerly the National Sanitation Foundation), a nonprofit testing organization that ensures filter manufacturers' claims.

The most effective type of treatment is to protect water from contamination in the first place. If the homeopathic "memory of water" theory has any merit—and many experts agree it does—the water we put into our bodies carries with it essences of everywhere it's been and everything it's touched. Many towns and cities have established source water protection programs. Call your local water company to inquire about such organizations.