Answering The Washington Post’s Questions About Bottled Water Safety
An article written by a Washington Post reporter that appeared in numerous newspapers, including The Seattle Times, reported two important facts about bottled water. The dangers of dehydration are far worse than the potential risks of being exposed to the microplastics, and the potential health effects stemming from microplastics in bottled water are “probably low.” Unfortunately, those two science-based conclusions were buried in a long, and largely inaccurate, story about what happens if you drink from a plastic water bottle left in a hot car.
Instead of leading with the essential takeaway – that dehydration is a prevailing public health threat – the Post led with speculative concerns that warm weather may cause microplastics to leach into bottled water. By carefully excluding evidence at odds with its conjecture, the Post exaggerated a very uncertain risk, overlooked regulatory safeguards and advice, and handed readers a slanted perspective.
Just the facts: microplastics in bottled water
The article emphasized the potential for single-use plastic bottles, typically made from polyethylene terephthalate (PET) plastic, to release microplastics when exposed to heat. The Post’s conclusion came from a 2023 study in which four common plastics released microparticles after they were weathered in a UV-light chamber and an incubator set to 37°C (98.6°Fahrenheit). However, the four types of plastic tested in this study (PS, PP, LDPE, and HDPE ) did not include PET plastic; therefore, the findings are irrelevant to the single-serve bottled water containers mentioned in the Post’s article.
The World Health Organization (WHO) in 2019 concluded that microplastics in drinking water pose no significant health risk at current exposure levels, as human studies show minimal absorption and no clear evidence of harm. WHO’s recommendation is that more research is needed, as well as establishing standardized methods for measuring and quantifying nano- and microplastics. This conclusion was confirmed in 2024, when the US Food and Drug Administration (FDA) said it was “not aware of scientific evidence that would support consumers being concerned about the potential level of microplastic or nanoplastic contamination in food, including bottled water."
The FDA’s conclusion is critical because the agency tightly regulates PET bottles, ensuring that chemical migration remains well within safe limits under normal use conditions. PET bottles are designed for safety and claims of significant chemical leaching in hot cars are not supported by good science. The fact of the matter is that bottled water is one of the most regulated food products, with no evidence of significant health risks from typical use.
Dehydration: a neglected danger
The article’s emphasis on potential microplastic risks overshadowed the critical importance of hydration. Experts cited in the article, such as Christopher Hine from the Cleveland Clinic, stressed that dehydration poses a far greater threat than trace microplastics.
The problem is that Hine’s sensible guidance was buried deep in the story. This was a mistake on the Post’s part because the dangers of dehydration are serious and well documented. According to the National Institutes of Health:
“[D]ehydration presents with symptoms ranging from mild thirst and fatigue to severe complications such as confusion, hypotension, and multiple organ dysfunction. Dehydration is a common cause of hospital admissions, contributing to significant morbidity and mortality while often complicating a range of medical conditions.”
The Post’s caution against drinking from plastic bottles in hot cars could discourage hydration, particularly for individuals who may be already dehydrated. This lack of balance undermines public health by prioritizing speculative risks over essential needs.
Economic and environmental considerations
From an economic perspective, single-serving size plastic bottles remain a cost-effective and accessible hydration option, carrying a price tag as low as 5 cents per ounce. Reusable glass or stainless steel bottles, recommended as alternatives, can have an upfront cost of $20-$50, which may be prohibitive for many consumers. Additionally, 100 percent recyclable PET plastic bottles are lightweight and durable for transport, unlike glass, which is prone to breaking, or stainless steel, which is far heavier.
The article’s push for alternatives ignored these practical trade-offs. The environmental impact of plastic waste is an understandable concern, but the evidence is clear: PET plastic bottles are widely recycled, and its carbon footprint is significantly smaller than the emissions generated by other materials.
Balanced Recommendations
Rather than urge readers to avoid plastic, the Post could have emphasized practical precautions: store bottles in cool, shaded areas; use them within a short time once opened; recycle them; and, most importantly, drink enough water. By prizing exaggeration over balanced reporting, the paper risked misinforming its audience and discouraging hydration—neither of which is desirable.