Quick Answer: Several contaminants in tap water are classified as known or probable carcinogens: arsenic (bladder, lung, skin cancer), PFAS compounds (kidney and testicular cancer), hexavalent chromium (lung cancer), trihalomethanes/haloacetic acids (bladder cancer), and nitrates (colorectal cancer at high levels). Reverse osmosis with carbon pre-filtration removes all of these at the point of use.
A new study conducted by scientists with the Environmental Working Group have very important results to share. The report found that contaminated tap water causes as much as 100,000 cases of cancer every year in the U.S. alone. This coming just a month after the earlier EPA report about lead levels in Newark water is a cause of concern for people across the country.
Sydney Evans, the lead author of the study said, “We want people to realize that water that meets legal specifications may still cause health risks based on the latest science. This is a concern nationwide, whether urban or rural, with a small or large [water system].”
What Causes The Risk?
The major risk comes from many elements that somehow find their way into the tap water. It is reported most of it is from naturally occurring arsenic which usually is found in groundwater and the byproducts of the chemicals used for disinfecting the water like chlorine or chloramine. Radioactive contaminants found a place in the report as well which was published in Heylion, a peer-reviewed journal. Even still, the number of water-connected cancer cases is less as compared to the total number of cancer cases in the country.
The American Cancer Society reported that in just 2018, 1.7 million new cancer cases had been registered. Even then, the Vice president of science investigations at the Environmental Working Group feels that water contamination plays a huge role in causing cancer. Olga Naidenko said that of all the cancer cases related to environmental causes, water contamination is responsible for a higher percentage of those.
Water In The U.S.
The country is ranked at a very decent spot worldwide for water quality as the country has been able to eliminate many biological causes of diseases and illnesses like the bacterium E Coli which are more commonly found in developing nations. However, the water seems to be unsafe as other contaminants pose to be a problem. Lead leaking from old pipes, underground arsenic, and disinfectants are just to name a few of the contaminants that are becoming difficult to deal with.
Problems like these are easily documented and perhaps even taken care of but the study also notes that contaminants in the water contribute a huge chunk of share for overall cancer risk associated with drinking water, in large communities. The study was conducted across the water quality levels of over 48,000 systems. Evans suggested that people check local water reports and get an individual filter for home if necessary. Even in Washington D.C., regulators found exceeded levels of 10 contaminants, standards that are more of recommendations rather than mandatory guidelines. Most of these contaminants are associated with cancer.
How Can Citizens Be Safe?
Presence of arsenic, lead, chlorine, and many other such elements have been found to cause cancer in as much as 100,000 cases across the country. In light of such an event, just like Evans suggested, it is recommended that families be aware of the local water quality reports available and if needed, get a residential filter to keep water safe for drinking.
AMPAC suggests Reverse Osmosis Water Filter that is especially known for getting rid of practically every contaminant including the 10 chemicals found by the D.C. regulators. An RO filter is an all in one package for protection against biological, organic and chemical impurities. It also removes suspended particles, total dissolved salts, and odor for a pleasant experience. You get stress-free water supply at your disposal in just a touch of a button. The filters are almost always automatic requiring no manual supervision. These also work according to the changing quality and impurity levels which make these products a must-have in today’s date.
If you need one such product or are looking for your local or home water quality report, you can contact AMPAC USA at (909) 548 4900 for quick assistance. Our experts are more than qualified to get the water tested for impurities and suggest the best option for you and your family. Contact us today!
The Environmental Working Group (EWG) Tap Water Database analysis of testing data from 49,000+ public water utilities found that hundreds of cancer-linked contaminants are detected in US tap water, with aggregate cancer risk from regulated contaminants at levels 2-500 times higher than EPA “acceptable risk” levels in many water systems. It is important to contextualize this finding: EPA MCLs are designed to balance risk reduction with economic feasibility, not to achieve zero cancer risk. The legal standard is not the same as the health-based standard.
Arsenic is classified as a Group 1 human carcinogen by IARC (International Agency for Research on Cancer), causing bladder, lung, and skin cancers with chronic exposure via drinking water. The current EPA MCL of 10 ppb reflects a compromise — the MCL was reduced from 50 ppb in 2001, but the health-based goal (MCLG) is 0 ppb because there is no demonstrated safe threshold. An estimated 2 million Americans consume water exceeding the MCL from private wells and small utilities. PFAS (PFOA and PFOS) are designated as “likely carcinogens” by EPA, associated with kidney and testicular cancers, with EPA’s 2024 MCL set at 4 ppt (parts per trillion) for each compound.
Disinfection byproducts (DBPs) including trihalomethanes (particularly chloroform and bromodichloromethane) and haloacetic acids are classified as probable carcinogens and are associated with bladder cancer risk in population studies. The challenge is that DBPs are formed by necessary disinfection — the public health benefit of disinfecting against microbial pathogens far outweighs the modest carcinogenic risk from regulated DBP levels. Activated carbon filtration at the point of use effectively reduces DBP concentrations and their precursors. A properly configured 5-stage RO system with carbon pre-filtration and post-filtration achieves meaningful reduction of arsenic, PFAS, hexavalent chromium, nitrates, and DBPs simultaneously.
Frequently Asked Questions
What specific contaminants in tap water are classified as carcinogens?
Several contaminants are known or probable carcinogens, including arsenic (linked to bladder, lung, skin cancer), PFAS compounds (kidney and testicular cancer), hexavalent chromium (lung cancer), trihalomethanes/haloacetic acids (bladder cancer), and nitrates (colorectal cancer at high levels). Radioactive contaminants and lead are also noted concerns.
How many cancer cases in the U.S. are attributed to tap water contamination annually?
A new study by the Environmental Working Group (EWG) estimates that contaminated tap water causes as many as 100,000 cases of cancer every year in the U.S. alone. This highlights a significant public health concern, even though water-related cases are a fraction of the total annual cancer diagnoses.
Is tap water that meets legal standards still safe from cancer risks?
No, not necessarily. According to Sydney Evans, lead author of the EWG study, water meeting legal specifications may still pose health risks based on the latest scientific findings. Legal limits often don’t account for cumulative exposure or the most recent understanding of contaminant toxicity.
What are the main sources of cancer-causing contaminants in tap water?
The primary sources include naturally occurring arsenic, often found in groundwater, and byproducts from chemical disinfectants like chlorine or chloramine used in water treatment. Additionally, lead leaching from old pipes and radioactive contaminants contribute to the overall risk.
What is the most effective way to remove cancer-causing contaminants from tap water at home?
Reverse osmosis (RO) with carbon pre-filtration is highly effective at removing a wide range of these contaminants, including arsenic, PFAS, hexavalent chromium, trihalomethanes, and nitrates, at the point of use. AMPAC USA engineers design robust systems leveraging this technology for comprehensive water purification.
Need a Water Treatment Solution?AMPAC USA engineers custom water purification systems for commercial, industrial, and emergency applications — from 500 GPD to multi-million GPD. Trusted by municipalities, military, and industry worldwide.
