A study published in the journal PLOS Water revealed that the San Francisco Bay Area’s drinking water is contaminated with cancer-causing chemicals.
Trihalomethanes (THMS) are cancer-causing compounds found in Bay Area drinking water. THMS are byproducts of the chlorination process, a water purification technique that kills bacteria to make water safer to drink.
While the study primarily focused on the San Francisco Bay Area, researchers indicated that the presence of THMS in water can affect Americans nationwide. Chlorination is the most common method of disinfecting water, and if not carried out properly, it leaves traces of THMS in the water.
According to the lead author of the research, Samantha Bear, they studied the differences between health contaminants and aesthetic contaminants of water. They found that many of the aesthetic properties of water are not related to health hazards. Aesthetic contaminants are those that change the smell and taste of water. While there is a common perception that aesthetic contaminants reduce water quality, this perception is often incorrect.
For a long time, American tap water has been considered safe to drink. However, there is a rising public perception that tap water may contain dangerous chemicals as it no longer tastes the same. These perceptions are mostly related to aesthetic contaminants and have led to increased bottled and treated tap water use nationwide. Apart from tap water, the Bay Area bottled and treated tap water has also been found to have THMS.
Data suggest that every American consumed 27.8 gallons of bottled water on average in 2010, which increased to 45.2 gallons per person in 2020. Incidents like the 2014 Flint water crisis increased the popularity of bottled water.
Many people increasingly prefer domestic water treatment systems, unaware that while these systems improve the water’s appearance and taste, they do not necessarily make it completely safe to drink.
Consistent exposure to THMS is extremely dangerous, as it can contribute to bladder and colon cancer, in addition to causing reproductive health issues among females.
Jessica Goddard, another scientist who contributed to the study, stated that the THMS levels in the drinking water did not violate the regulatory limits. However, they were still more than the recommended limits for healthy water. At its current limit, the water still poses long-term health hazards.
Bear advised people not to use bottled water but to invest in a good quality and customizable home water treatment system that can allow you to purify your tap water according to its contaminants.
Meanwhile, Goddard demanded more stringent THMS legislation so that even people who cannot afford to treat their tap water themselves can get safe drinking water.
