This article originally appeared on Live in the Now.
Did you know that the average adult human body is 55 percent to 60 percent water? (Babies’ bodies are closer to 75 percent.) The brain is made up of about 70 percent water, and the lungs, closer to 90 percent. This means that the quality of the water you drink has an enormous impact on the quality of your health.
Unfortunately, high-quality drinking water is increasingly difficult to come by in this day and age. Most health conscious Americans know that, while we are lucky in this country to have access to water that is largely free of disease-causing microorganisms, drinking plain old, unfiltered tap water is generally not a great idea.
What’s wrong with tap water?
According to the Environmental Working Group’s National Drink Water Database, analyses of municipal drinking water have shown that, despite government regulations, there are still many dangerous contaminants present in our water, even after it has gone through municipal water treatment facilities.
In fact, these water treatment facilities often actually contribute to the problem by adding dangerous chemicals like fluoride and chlorine to water as part of the treatment process.
The water regulations and treatment methods used in the United States are outdated and do little to address the assortment of toxic chemicals that are currently present in our environment.
The Safe Drinking Water Act only regulates 91 potential water contaminants. Yet there are more than 60,000 chemicals used within the United States, many of which have been identified as probable carcinogens. According to some estimates, there are now more than 2,100 known chemical toxins present in U.S. tap water. Additionally, many municipalities transport their water in antiquated, corroded pipes, which may leach toxic heavy metals into the water after it has been treated.
Here’s a rundown of some of the chemicals that are more than likely lurking in your tap water:
For over 50 years, the U.S. government has mandated that fluoride be added to the water supply to prevent dental problems. However, current research has shown that fluoride, a chemical that is used in rat poison, does a lot more harm than good. The fluoride found in tap water has actually been shown to damage tooth enamel, increase fracture risk, suppress immune and thyroid function, increase cancer risk and disrupt the function of the pineal gland.
Many European countries have banned the use of fluoride altogether, and there is a large activist movement of people working to get fluoride banned in the United States. Visit FluorideAlert.org to learn more.
Water treatment facilities use chlorine as a disinfectant. It effectively kills microorganisms, but also has toxic effects on the human body. Chlorine has been identified as a leading cause of bladder cancer, and has been associated with rectal and breast cancers, asthma, birth defects and premature aging of skin.
3. Radioactive Contaminants
Radioactive fallout from Japan has been detected in drinking water supplies throughout the United States. In 2011, it was reported that radioactive iodine-131 was detected in drinking water samples from 13 U.S. cities. Radioactive cesium and tellurium isotopes have also been detected at low levels in some cities.
The Environmental Protection Agency (EPA) has said that the levels are well below public-health concern, but that it continues to monitor the situation. (You can view this data on the EPA’s website.)
4. Pharmaceutical Drugs
Investigations have shown that an increasing number of pharmaceutical drugs are finding their way into our drinking water. Drugs ranging from antibiotics and birth control pills to painkillers, antidepressants and other psychiatric medications are now showing up in most municipal water supplies.
5. Hexavalent Chromium
In 2011, an Environmental Working Group report revealed that the chemical hexavalent chromium (or chromium-6) is present in high concentrations in 31U.S. cities. This is the chemical made famous by the movie, “Erin Brockovich,” which chronicled the case brought against Pacific Gas and Electric for contaminating the water in an area of Southern California and poisoning thousands of people. Yet, despite its known toxicity, there are no government regulations for hexavalent chromium in drinking water.
6. Lead, Aluminum and Other Heavy Metals
Lead and other heavy metals can make their way into your tap water through corrosion of the pipes in your plumbing system. Lead consumption has been linked to severe developmental delays and learning disorders in children. Aluminum and other heavy metals have been linked to nerve, brain and kidney damage. Currently, some municipalities still transport water in lead pipes.
Arsenic is a poisonous element known to be extremely carcinogenic. The Natural Resources Defense Council estimates as many as 56 million Americans drink water containing unsafe levels of arsenic. For more information, see the USGS website, which offers maps showing where and to what extent arsenic occurs in ground water across the United States.
 Villanueva CM et al. Total and specific fluid consumption as determinants of bladder cancer risk. International Journal of Cancer. April 2006; 118:8, 2040-47.
 McMahon J. Radiation Detected In Drinking Water In 13 More US Cities, Cesium-137 In Vermont Milk. Forbes. 2011 April 9. Retrieved from: http://www.forbes.com/.