Is Tap Water Safe To Drink?

EWG found 22 carcinogens commonly found in tap water including arsenic, byproducts of water disinfectants and radionuclides such as radium and uranium could cumulatively result in over 100,000 cases of cancer over the span of a lifetime. 

Even though most American tap water meets the minimum legal standards set by officials, the group found that contaminates that remain present in tap water create a real and measurable risk for cancer. 

"The vast majority of community water systems meet legal standards," said Olga Naidenko, the vice president for science investigations at EWG, in a statement. "Yet the latest research shows that contaminants present in the water at those concentrations — perfectly legal — can still harm human health."

Another study conducted by EWG in California examining tap water found that a cumulative analysis of contaminants commonly found in tap water increased the risk of cancer for 15,000 residents.

The risk of these carcinogens has been under debate for decades by experts who caution standards set for community water systems that are regulated by the EPA are complicated and require a balance between cost and safety. 

As is turns out tap water is not as safe as you may think: The 22 contaminants with carcinogenic risks were commonly found present in 48,363 community water systems within USA which serve around 86% of the American population; and cumulative risk assessment has found that per 10,000 people four will have cancer over the span of their lifetime due to the contaminants in the tap water. 

"Drinking water contains complex mixtures of contaminants, yet government agencies currently assess the health hazards of tap water pollutants one by one," said Sydney Evans, the lead author of the paper, in a statement. "In the real world, people are exposed to combinations of chemicals, so it is important that we start to assess health impacts by looking at the combined effects of multiple pollutants."

Within the scope of this study the majority of American water systems were in compliance with EPA standards, and the legal limits are set for over 90 contaminants in drinking water, despite this 87% of the cancer risk present in tap water comes from arsenic and byproducts of common disinfectants, meaning there is a need for a change in standards for public drinking water.

According to W.H.O long term exposure to arsenic can cause skin, bladder, and lung cancers; and byproducts of disinfectants are classified as possible human carcinogens that are known to cause liver and bladder cancers according to NIH. 

It was noted that possible contaminants present in groundwater from private wells, were not taken into account, nor was the heightened risk of carcinogens in vulnerable populations such as infants, children, elderly, and those who are ill. 

Flint, Michigan and Newark, New Jersey drinking water crises have revealed real complications and serious failures in the management of American public water systems from water sources to the pipelines themselves. 

Under the Safe Drinking Water Act the EPA regulates public drinking water, and is required to set standards for contaminants through the National Primary Drinking Water Regulation to minimize risk for contaminants. The water regulations primarily focus on contaminants that may cause the greatest health risk which has been split into 2 categories: 1) the maximum contaminant level which is enforceable by law and is less stringent, and 2) the maximum contaminant level goal which is only a health guideline. 

To put this into perspective: The federally mandated MCLG for arsenic is 0 micrograms per liter, while the MCL is 10 micrograms per liter, and the EWG recommends only 0.0004 micrograms of arsenic at maximum be allowed in public water. 

Installing a water filter system in your home can help to remove contaminants found in an individual water source, however the ones that specifically remove arsenic are costly to purchase but in the long run risk to health makes the cost acceptable. 

Most experts are recommending a broader scale and are advising solutions aimed at decreasing the level of contaminants present in public tap water from the supply. "We need to prioritize source water protection, to make sure that these contaminants don't get into the drinking water supplies to begin with," Naidenko said in a statement.

Advanced technology already exists today that can remove carcinogenic substances from water, the biggest hurdle to them is the cost to implement them. But in the big picture this cost is more than offset by the long term savings in healthcare. 

"Typically," Sedlak said to USA TODAY, "these additional treatment processes are paid for by consumers — and in many cases, members of the public have been unwilling to see large rate increases in their water bills."

"The public is responsible for helping local water suppliers to set priorities, make decisions on funding and system improvements, and establish programs to protect drinking water sources," the EPA writes.

"If people are aware of the health impacts (of tap water), they might be willing to pay more for water treatment," said Sedlak. "But at this point, the EPA has made their decision."