Drinking clean, pure water is essential for optimal health, yet more than 2 billion people worldwide still lack access to safe drinking water.1 The increasing contamination of tap water with hazardous substances has led many people to seek alternatives such as bottled water and home filtration systems in an effort to protect their well-being.
However, despite these changes, there is still a lack of comprehensive scientific data on the safety of these water sources, especially with regard to the presence of hazardous chemicals and contaminants. This led researchers in California to examine the safety and aesthetic qualities of three common drinking water options: bottled water, tap water, and household tap water.
Recently published in the journal PLOS Water2 Their findings show alarming levels of carcinogenic chemicals and other dangerous contaminants across all types of drinking water, raising concerns about whether water is actually safe to consume.
Cancer-linked chemicals found in drinking water
To perform the analysis,3 Researchers collected 100 bottled water samples from 89 different brands, 603 tap water samples, and 111 household tap water samples from the San Francisco Bay Area. They tested for 100 different contaminants, including metals, volatile organic compounds (VOCs), disinfection byproducts and microbial indicators, as well as assessed factors that influence consumers’ water choice, including taste, odor and color.
One of the most surprising findings was the widespread presence of trihalomethanes (THMs) in all drinking water sources tested. THMs are a group of disinfection byproducts formed when chlorine used to treat drinking water reacts with natural organic matter in the water. THMs are known carcinogens and have been linked to increased liver toxicity as well as reproductive and developmental problems.
Studies have shown that tap water samples contain the highest concentrations of these chemicals, accounting for 94.5% of total cumulative toxicity. Meanwhile, THMs accounted for 76.7% of the total toxicity observed in household tap water.
The researchers also found that 2% of tap water samples exceeded the THM regulatory limit (set at 80 micrograms per liter). This is already a higher standard than what is considered safe for long-term health. In tap water treated for domestic purposes, 25% of samples still contained chloroform, a common THM, at concentrations exceeding health protection standards.
In addition to THMs, the study found significant levels of heavy metals in both tap water and domestically treated water. Lead was found in 51% of tap water samples and 30% of samples treated at home, a result of aging water infrastructure and corroded pipes, the researchers said. Exposure to lead, especially in children, causes severe neurological damage and developmental delays.
Additionally, arsenic was found in 8% of home-treated and 3% of tap water samples, and uranium was found in 2% of both home-treated and direct tap water samples. Both pollutants pose serious long-term health risks, including cancer and kidney damage.
Bottled water is not a safer alternative
Consumers often switch to bottled water due to concerns about the taste or safety of tap water, but the featured study found that4 It turns out that bottled water isn’t necessarily a safer choice. Although overall toxicity was generally low, it was not free from contamination.
Researchers found that 8 percent of bottled water samples exceeded California’s strict regulatory limits for THMs, and chloroform was detected in 32 percent of the samples. Interestingly, some petroleum-derived compounds, including benzene and toluene, were detected only in bottled water and not in tap water or household treated samples. The researchers said:5
“Additional detections and exceedances in bottled water (BW) suggest that bottle production and processing may impact water quality. Two petroleum-derived compounds (benzene and toluene) were detected only in BW.
One benzene detection exceeded health standards, and all five toluene detections were below health standards. “One possibility is that these contaminants may have been introduced into bottled water products during processing.”
Another surprising finding was the prevalence of heterotrophic bacteria in bottled water, found in 43% of samples. Although these bacteria are not typically associated with pathogens, their presence contradicts the common perception of bottled water as a purer alternative. According to the author:6
“These findings support previous studies that identified heterotrophic plate counts (HPCs) in BW detected in 30% to 71% of samples. Although tap water samples are also likely to have HPCs due to their ubiquitous presence in the environment, these findings is particularly interesting in BW because of its marketing claims of purity.”
The results challenge the assumption that bottled water is inherently safer or cleaner than tap water. Both sources have their own risks, and while bottled water solves some of the aesthetic concerns, it still has quite a few health concerns to watch out for.
Bottled water also exposes you to endocrine disrupting chemicals.
Using plastic water bottles poses additional health concerns beyond the contaminants found in the water itself. main research7 We focused on two main categories of endocrine-disrupting chemicals (EDCs) associated with plastic water bottles: microplastics and perfluoroalkyl substances (PFAS). Long-term exposure to these EDCs through regular consumption of bottled water can have cumulative health effects.
Microplastics either leach from the plastic bottles themselves or are present in water sources. In fact, a January 2024 study found that8 A study published in the Proceedings of the National Academy of Sciences found that consumers can ingest about 240,000 tiny plastic particles per liter of bottled water.
Microplastics contain a variety of additives and chemicals, including bisphenols (e.g. BPA and its alternatives), phthalates, and heavy metals, which disrupt the endocrine system in several ways.9 Bisphenol mimics estrogen and is known to cause hormonal imbalances, reproductive problems, and certain cancers.10 Phthalates, on the other hand, are associated with anti-androgenic effects and affect reproductive health and development.11
2021 study on PFAS (aka “forever chemicals”)12 A study conducted by researchers at Johns Hopkins University found this ingredient in 39 of more than 100 bottled water samples tested. PFAS enter bottled water through contaminated source water, manufacturing processes, or cross-contamination.
These chemicals interfere with thyroid function, leading to metabolic disorders and developmental problems. It has also been linked to reduced fertility, altered immune function, and increased risk of cancer.13
EWG’s Tap Water Database — What contaminants are in your water?
If you want to know what other contaminants are lurking in your water, you can obtain local drinking water analysis results from your water utility. It is your right to view the annual water quality report for your area. This report highlights contaminants of concern (there may be others that are legally “safe” but still pose long-term health risks).
The Environmental Working Group (EWG) also provides a comprehensive tap water database where consumers can access detailed information about the quality of their local drinking water. This database provides insight into contaminants detected in municipal water supplies, including their levels and potential health risks.
Simply enter your zip code to learn about specific pollutants found in your area, including lead, chlorine, and various pesticides. This resource will help you make informed decisions about water quality and encourage improved standards by local public agencies.
Invest in a high-quality filtration system for your home
As the results of the special study came out,14 As concerns have been raised about the effectiveness of some water purification systems, the authors emphasized that “home-scale water treatment may reduce the potential for aesthetic concerns and health risks to tap water.”
The key is to select a system designed to effectively remove contaminants present in the water supply. One of the best water filters I have found so far is the Pure & Clear Whole House Water Filtration System. The system uses a three-stage filtration process (micron sediment pre-filter, KDF water filter and advanced carbon water). filter15 — Filters out chlorine, detergent by-products and other contaminants.
Ideally, the best practice is to filter water both at the point of entry into the home and at the point of use. This means installing a filter in the main water pipe that enters your home, and again in specific locations where water is consumed or used, such as the kitchen sink or shower.
For additional guidance, EWG offers a helpful water filter guide that you can search by filter type, technology, and specific contaminants. This resource will help you make an informed decision about which filtration system is best for your home.16
More Ways to Protect Your Drinking Water
In addition to using a high-quality water filtration system, here are some effective strategies to help protect the quality of your home’s drinking water while contributing to a healthier environment:17
1. Stay informed about local water quality Check reports from your local water supplier regularly. This report provides details on contaminant levels, safety compliance, and recommendations. You may also receive a local drinking water quality report from the U.S. Environmental Protection Agency (EPA).
2. maintain plumbing systems; This is especially true if your home has old pipes made of lead or galvanized metal. Regular inspections and replacing old pipes can help prevent harmful substances from leaching into your water.
3. Store bottled water correctly By storing in a cool, dark environment. Do not leave in warm places or in direct sunlight. Plastics can break down and release chemicals into the water. Even better, avoid using plastic water bottles and instead choose glass or stainless steel containers.
4. Adopt good environmental practices Reducing plastic use and participating in local clean-up activities by properly disposing of hazardous substances such as chemicals and medicines also protects water resources.
5. Test your water regularly, This is especially true if you use well water or live in an older home. Home water quality testing kits can help you identify contaminants such as lead, nitrates, and bacteria so you can take appropriate steps to ensure your water is safe.
Progesterone mitigates the effects of EDCs in bottled water.
The simplest way to effectively minimize your exposure to endocrine disrupting chemicals (EDCs) from plastic water bottles is to stop using plastic water bottles altogether. Instead, use glass or stainless steel containers to store water.
However, if you frequently use bottled water or are exposed to other sources of EDCs in your environment, you may want to consider using transmucosal progesterone combined with vitamin E via buccal or gingival administration (i.e., rubbed into the gums) to counteract them. Harmful effects of these chemicals.
Progesterone is a hormone that acts as an “off” switch on the activity of estrogen, helping to mitigate the effects of phthalates and other estrogenic compounds. By counteracting the effects of these destructive chemicals, progesterone helps restore balance to the body’s hormonal systems.
