When we buy bottled water, we genuinely believe that it is safe to drink, but things are not like that in reality, as a recent study by the Environmental Working Group (EWG) revealed. Tests have shown that every bottled water brand contains chemical contaminants that make them just as “healthy” as tap water.

We pay approximately 1,900 times more to drink bottled water, compared to tap water, and we must admit that most of us buy it under the impression that it is somewhat “pure,” straight from the mountain springs, no chemicals, just water. But that’s just a myth, and EWG’s own tests are a proof of that.

While the industry actively refused to reveal any data on its products, consumers have the right to know that in California for example, several Sam Choice samples were found to exceed the legal limits of contaminants in that state. Furthermore, in other four states – North Carolina, Virginia, Delaware, Maryland – but also in the District of Columbia and California, the bottled water was found to contain cancer-causing contaminants above all legal limits.

The study found that while in California, the legal limit of trihalomethanes (TTHMs) in bottled water is of 10 parts per billion (ppb), Walmart’s Sam’s Choice contained 37 ppb TTHMs; furthermore, Giant’s Acadia contained 36 ppb TTHMs in Washington DC; the same Walmart’s Sam’s Choice also contained 13 ppb bromodichloromethane, which according to the California Cancer Safety Standard, should be of 2.5 ppb. Sam’s Choice and Acadia purchased in other states also revealed levels twice above the legal standards.

EWG also found that 2 out of 10 brands tested, mentioned above, also contained standard municipal water treatment, which means customers buy tap water, nicely bottled and with a huge price. In addition to that, the two brands were also found to exceed safety standards for bottled water.

In that respect, Sam’s Choice samples purchased in the San Francisco bay area contained disinfection byproducts which have been linked to cancer and reproductive problems. EWG announced it filed a suit to ensure Walmart will post a warning sign on its bottles that the water contains a chemical known to the State of California to cause cancer.

Other brands were also found to contain, in addition to the already mentioned chemicals, other pollutants such as caffeine and pharmaceuticals (Tylenol), heavy metals and minerals, including arsenic and radioactive isotopes, as well as fertilizer residue, and other chemicals.

According to assays for breast cancer proliferation conducted by the University of Missouri, one bottled water brand increased the growth of breast cancer cells by 78 percent in four days.

As less people use tap water for drinking, and more start buying bottled water, they should know the risks they are exposed to. According to EPA, bottled water could be less or more treated than tap water, which means it is not necessarily healthier, but just expensive. Furthermore, the bottled water industry is not required to disclose data on the water composition, which makes consumers unaware of what they are paying for.

EWG’s recommendation: “consumers should drink filtered tap water instead of bottled water.” Setting up a water filter will prove not only cheaper, but apparently more efficient.