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JANE IN MARYLAND ASKS:
I have had a cooler of single-use plastic water bottles sitting in my garage since July, when, after one of my daughter’s swim meets, they mysteriously appeared there. I try not to buy or use plastic water bottles and I haven’t touched them since. The temperature of our garage is not regulated, and they’ve been through super hot summer days and weeks of below freezing winter weather. Are plastic water bottles safe after all this? Should I throw this water out before the next swim season begins?
Tell Congress: Burning Plastic Is Not a Solution to the Plastics Crisis
MOM DETECTIVE ANSWERS:
It’s funny how plastic water bottles sneak into our lives, no matter how hard we try to avoid them. Sometimes they’re unavoidable, usually on airplanes and in hospitals. Maybe you forgot your reusable bottle at home and a thirsty screaming kid forced your hand. Or maybe your tap water is contaminated with toxic chemicals or lead. Still, someone ditching them in a garage is unusual! But plastic happens to the best of us.
It’s wild to think only a few decades or so ago no one bought water in plastic bottles and now it’s a mega industry. According to the organization Beyond Plastics, one million plastic bottles are bought around the world every minute and more than half a trillion plastic bottles, give or take a few, are being sold annually. From manufacture to disposal, this outrageous amount of plastic bottles is a disaster.
Plastic is made from chemicals derived from fossil fuels, a.k.a. petrochemicals, and its production is horrific for our planet and health—especially the families who live closest to plastic manufacturing plants. And the sheer waste is overwhelming to consider. At best, less than a third of all plastic bottles will be recycled. Mostly these single-use bottles clog our waterways—at least 15 million metric tons of plastic enter the ocean each year, says Beyond Plastics. They also poison aquatic life—and people, when we eat fish. Some experts predict that plastic will outweigh fish in the ocean by 2050 if we don’t all start embracing comparatively cheaper tap water in our own reusable containers ASAP. Plastic water bottle safety is also a rampant and growing health issue as chemicals in plastic can and do get into our drinking water, and can make us sick.
What is in those water bottles
Most single-use plastic water bottles are made from polyethylene terephthalate (PET or plastic #1). This plastic is only meant for one use. Even though it’s considered a “safer” plastic, compared to, say, vinyl (plastic #3), it’s still constantly shedding small pieces of plastic (micro- and nanoplastics) into drinking water. A recent study determined that an average liter of water in a plastic bottle contains about 240,000 tiny pieces of plastic. Yuck.
The water can also contain chemicals coming from the PET. Reports have discovered at least 150 chemicals are known to leach from PET plastic beverage bottles into the liquid inside including lead and antimony, heavy metals with well established health harms, as well as BPA, a hormone-disrupting chemical, and PFAS, “forever chemicals” that have been linked to decreased fertility, cancer, liver damage, thyroid problems, adverse birth outcomes, and more. Research on the health impacts of microplastics is really just starting to ramp up, but the tiny plastic particles have already been linked to Parkinson’s disease, hormone disruption and reproductive effects, cancers, and heart attacks and stroke. It’s not just the bottles, though. Even the caps can dump extra microparticles into your drinking water as they get twisted off and screwed back on.
Considering you have already made the commonsense decision to avoid plastic water bottles, you likely already know all of this. So here are my thoughts on how to make a decision about your unique situation:
Temperature change and plastic
Heating plastic encourages it to leach its chemical components into whatever it’s containing, in this case the water of mysterious origin in your garage. Sunlight, hot liquids, heating, and microwaving are all known to break down plastic. Ditto warm environments. PET bottles are even more likely to leach chemicals if they’re recycled or reused.
There are studies that have been done in countries with extreme heat, like Kuwait, that found antimony, which may affect the liver and gastrointestinal system, leaching from PET plastic water bottles at very high temperatures, like above 120°F. The hotter the temperature, the higher the rate of chemical leaching from plastic into bottled water. Other chemicals, including BPA, have also been studied for chemical migration based on storage conditions. Even if it’s not Kuwait-hot in your garage, it’s likely hot enough to degrade plastic to some extent in the summer. This is why it’s not a good idea to leave PET bottles in the sun on car dashboards, for example.
Freezing appears to be less of a concern when it comes to plastic and chemical migration. It’s less studied as a result. However, freeze-thaw cycles (when plastic freezes then thaws multiple times) studied in agricultural settings—but not on PET specifically—have been shown to “stress” plastic, which can lead to microplastic shedding. To minimize chemical migration, PET is best stored at room temperature with no exposure to direct sunlight.
Time on shelf (or garage in your case)
The length of storage time can also impact the amount of chemical migration from plastic bottles. Long storage time, defined as weeks to months, can decompose PET, triggering it to release contaminants into the water it contains. Long storage time plus high heat equals more chemicals leached and more plastic degraded into microplastics.
Jane, to be honest I’m struggling to answer your question. I want to leave it up to you to decide what to do with this damning information because I hate the idea of telling anyone to toss even more plastic. But also, no, I would not drink this mystery water after many months and temperature fluctuations. And I certainly would not allow an entire swim team of children to gulp it down either. Children are uniquely vulnerable to the toxic chemicals in plastic. I have a feeling I know what you’re going to decide. And I’m raising a glass of filtered tap water in your direction: Cheers!
Tell Congress: Burning Plastic Is Not a Solution to the Plastics Crisis