Cancer remains one of the most serious global health threats, with its impact projected to grow dramatically in the coming decades.
According to the National Cancer Institute, there were nearly 20 million new cancer cases and 9.7 million cancer-related deaths worldwide in 2022 alone. These numbers are expected to rise significantly by 2040, with an estimated 29.9 million new cases and 15.3 million deaths annually. While genetics and lifestyle factors contribute to cancer risk, growing attention is being given to environmental exposures like drinking water.
Contaminants have been increasingly detected in public water systems across the globe. These harmful substances have been linked to various forms of cancer, including kidney, liver, and testicular cancers. As water pollution continues to pose a threat to public health, understanding the connection between contaminated drinking water and cancer risk is essential.
Common Carcinogenic Contaminants in Drinking Water
Research strongly indicates that prolonged exposure to specific drinking water contaminants elevates the risk of various cancers. A study analyzing cancer incidence in Arizona against water contamination data from the EWG revealed positive correlations between several contaminants and cancer.
Notably, bladder and pancreatic cancer showed associations with multiple studied contaminants, while colorectal cancer risk was linked to radium and uranium exposure. Furthermore, a statistically significant link was found between disinfection byproducts (DBPs) and leukemia, underscoring the potential health risks associated with water contamination.
The most concerning chemicals are:
Arsenic, a naturally occurring element, can enter water supplies through the erosion of natural deposits or industrial and agricultural pollution. It has been strongly linked to skin, bladder, and lung cancers, even at relatively low exposure levels.
Disinfection byproducts (DBPs) form when disinfectants like chlorine react with naturally occurring organic matter in water. Trihalomethanes and haloacetic acids, two common DBPs, have been associated with bladder cancer and potentially colorectal cancer through both ingestion and inhalation during bathing.
Hexavalent chromium, made famous by the Erin Brockovich case, enters water through industrial discharge and natural deposits. This potent carcinogen has been linked to lung cancer when inhaled and stomach cancer when ingested through contaminated water.
Radioactive contaminants, including radium and uranium, occur naturally in some groundwater sources and can cause various types of cancer. These elements are particularly concerning because they can accumulate in bones and tissues over time.
Industrial Pollution and Cancer Clusters
Industrial discharge into water sources remains one of the most significant contributors to carcinogenic contamination. Manufacturing facilities, chemical plants, and mining operations can release substantial quantities of cancer-causing substances into nearby waterways. These contaminants may then enter municipal water systems or private wells, potentially affecting thousands of residents.
Cancer clusters, which are higher-than-expected numbers of specific cancers within a geographic area and time period, have been identified in multiple communities. These clusters are often found in areas with documented industrial water contamination.
The Clean Water Act (CWA), established in 1972, provides the framework for regulating pollutants in U.S. waters. Under the CWA, the EPA sets wastewater standards for industries and develops water quality criteria to protect public health and the environment.
AFFF Contamination at Military Bases
Aqueous Film-Forming Foam (AFFF) has become one of the most significant emerging threats to water safety and public health. Developed in the 1960s, AFFF was widely used by military bases, airports, and firefighting training facilities due to its effectiveness in extinguishing fuel fires.
However, TorHoerman Law notes that the foam contains per- and polyfluoroalkyl substances (PFAS), such as PFOS and PFOA. These substances are highly persistent in both the environment and the human body.
The slow regulatory response to PFAS contamination has worsened the situation. The EPA has only recently begun setting health advisories and enforcing standards for these chemicals. Meanwhile, the AFFF foam lawsuit has been filed against its manufacturers by those who developed cancer potentially linked to PFAS exposure.
According to AboutLawsuits.com, 80% of U.S. military bases are linked to high levels of PFAS contamination. The Department of Defense plans to prioritize addressing PFAS contamination in private, off-base drinking water systems. The EPA’s new rule establishes enforceable PFAS drinking water limits, acknowledging the threat they pose to public health.
Agricultural Runoff and Nitrate Contamination
Modern agricultural practices contribute significantly to water contamination through runoff containing fertilizers, pesticides, and herbicides. Nitrates, primarily from fertilizers and animal waste, are particularly concerning due to their mobility in groundwater and potential health impacts.
High nitrate levels in drinking water may increase the risks of colorectal cancer, ovarian cancer, thyroid cancer, kidney cancer, and bladder cancer. Rural communities relying on private wells in agricultural regions face the highest risk from nitrate contamination. These water sources aren’t subject to the same regulatory monitoring as public systems.
According to NPR, the EPA’s nitrate limit is 10 milligrams per liter, but growing research suggests health risks even at levels below this threshold. The EPA has spent over two decades urging states to reduce runoff, particularly in areas like Iowa. Iowa has high rates of both nitrate pollution and cancer.
Aging Infrastructure and Lead Contamination
America’s aging water infrastructure presents another significant pathway for cancer-causing contaminants to enter drinking water. Lead service lines and plumbing fixtures can leach lead into drinking water, particularly when water chemistry changes.
Studies have suggested associations between lead exposure and increased risks of kidney cancer and brain cancer.
Beyond lead, deteriorating infrastructure can introduce other contaminants and create conditions where cancer-causing chemicals form or persist. For instance, when water mains break or water pressure drops, contaminants from surrounding soil can enter the system. Additionally, aging water treatment facilities may not be equipped to remove emerging contaminants using conventional methods.
Frequently Asked Questions
How can I determine if my home’s drinking water contains carcinogenic contaminants?
To determine if your home’s drinking water contains carcinogenic contaminants, consider having it tested by a certified laboratory. Look for common pollutants like arsenic, nitrates, or disinfection byproducts. You can also check local water quality reports or contact your water supplier for specific contaminant data.
What types of water filtration systems are most effective for removing cancer-causing contaminants?
No single filtration system removes all potential carcinogens, so your choice should be based on the specific contaminants in your water. For most carcinogenic heavy metals (arsenic, chromium, lead), reverse osmosis systems provide excellent removal rates. Activated carbon filtration effectively reduces many organic carcinogens, including certain pesticides and disinfection byproducts. For PFAS compounds, a combination of reverse osmosis and high-quality activated carbon provides the best protection.
Can brief exposure to contaminated water (like during a vacation) significantly increase cancer risk, or is long-term exposure required?
Cancer development typically requires prolonged exposure, usually years or decades, rather than brief exposure during a short visit. Carcinogenesis is generally a multi-stage process where cellular damage accumulates over time, eventually leading to uncontrolled cell growth. The body has mechanisms to repair limited DNA damage from brief exposures, but these mechanisms can be overwhelmed by continuous exposures.
The growing presence of carcinogenic contaminants in our drinking water requires urgent attention from regulators, utilities, and communities. As we better understand the exposure effects, it’s clear that current regulatory standards may not sufficiently protect against cancer risks from many contaminants.
While complete elimination of all cancer-causing substances from drinking water may not be immediately achievable, significant risk reduction is possible. For individuals, awareness and appropriate filtration can provide important protection while broader systemic solutions are implemented.
