Your Bottled Water Might Not Be as Pure as You Think
We’ve all been there—grabbing a bottle of water off the shelf, assuming it’s the safer, cleaner choice compared to tap water. But here’s where it gets controversial: a groundbreaking study has uncovered dozens of unregulated harmful chemicals lurking in some of the most popular bottled water brands. And this is the part most people miss: while these chemicals are present, bottled water might still be less contaminated than tap water. Confused? Let’s dive in.
A recent study published in Science Direct analyzed 64 regulated and unregulated disinfection by-products (DBPs) in 10 major bottled water brands. The shocking result? Every single brand contained DBPs. But before you panic, Susan Richardson, a chemistry professor at the University of South Carolina and one of the study’s authors, offers a nuanced perspective: ‘The bottled waters we tested were less contaminated with DBPs than tap water.’ This finding flips the script on what many of us assume about bottled water’s purity.
Why Does This Matter?
Disinfection is a critical step in water treatment, protecting us from deadly diseases like cholera and typhoid. However, this process can inadvertently create DBPs, which have been linked to serious health risks, including bladder cancer, colorectal cancer, and even miscarriage and birth defects. But here’s the catch: while these risks are real, the levels of DBPs in bottled water are generally lower than in tap water, according to the study.
What’s Really in Your Bottle?
The study didn’t name the brands tested, but it did reveal some patterns. ‘Grocery’ and ‘name’ brands tended to have higher levels of DBPs compared to ‘designer’ brands. Spring water sources generally showed lower DBP levels than purified water. Two ‘grocery’ brands, which used purified tap water, had alarmingly high cytotoxicity levels—43 and 83 times the average of other bottled waters. Is your go-to brand one of them? We can’t say for sure, but it’s a question worth asking.
DBPs can sneak into bottled water through various routes. Some brands use tap water that’s been further purified, but not all DBPs are removed in the process. Others treat water with ozone, an effective disinfectant that can ironically create DBPs. Even spring water isn’t immune—it can be contaminated by surface waters containing DBPs. Among the most concerning DBPs found were brominated compounds like dibromoacetonitrile, a known carcinogen that remains unregulated. Should we be worried? The levels are low, but the lack of regulation is a red flag.
The Regulation Gap
The FDA does regulate some DBPs in bottled water, such as bromate and haloacetic acids, but many others remain unchecked. The EPA doesn’t regulate these chemicals in tap water, and by extension, they’re not regulated in bottled water either. Is this a loophole in our safety net? It’s a debate worth having.
What the Experts Are Saying
Sherri Mason, director of Project NePTWNE, argues that tap water is still safer due to its rigorous testing and lower levels of other contaminants like microplastics. Natalie Exum, a professor at Johns Hopkins Bloomberg School of Public Health, agrees that unregulated DBPs are a concern but notes that bottled water generally has fewer DBPs than tap water. Vasilis Vasiliou, from Yale School of Public Health, highlights the striking discovery of over 50 unregulated DBPs in bottled water, challenging assumptions about its purity. So, which is safer? The experts are divided, and the answer isn’t black and white.
What Happens Next?
Despite the findings, Susan Richardson advises against ditching tap water for bottled water unless there’s a known contamination issue. Why? The environmental cost of plastic bottles and the higher expense of bottled water are hard to ignore. But the study does underscore the need for expanded regulation of DBPs in public drinking water to protect public health.
Now It’s Your Turn
Do you trust bottled water more than tap water? Are you concerned about the unregulated chemicals found in this study? Or do you think the environmental impact of bottled water outweighs its perceived benefits? Let’s start a conversation—share your thoughts in the comments below!
