Is It Safe to Reuse Plastic Water Bottles?

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Is it safe to reuse plastic water bottles?

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Reusing plastic water bottles offers notable environmental benefits, including waste reduction and energy savings. However, it is crucial to consider the potential health risks, such as chemical leaching and microplastic release. Ensuring proper cleaning and handling practices can mitigate some of these risks, making the reuse of plastic bottles a safer and more sustainable option.

The reuse of plastic water bottles has become a common practice due to growing environmental concerns and the need to reduce plastic waste. However, questions about the safety and health implications of reusing these bottles persist. This article explores the potential risks and benefits associated with reusing plastic water bottles, drawing on recent research findings.

Environmental Benefits

Reusing plastic water bottles can significantly reduce plastic waste and its associated environmental impact. A study on the thermal performance of plastic bottles reused in building construction highlights the environmental benefits of repurposing plastic bottles. The research demonstrated that using plastic bottles as building materials can contribute to energy savings and thermal comfort, thus offering an alternative to traditional construction materials and reducing ecological imbalance.

Health Risks

Despite the environmental advantages, there are health concerns related to the reuse of plastic water bottles. One major issue is the potential for chemical leaching. Chemicals from the plastic can migrate into the water, posing health risks to consumers. Additionally, bacteria can accumulate in reused bottles, further increasing health hazards.

Microplastic Release

Another concern is the release of microplastics (MPs) from plastic bottles. Research has shown that mechanical stress, such as opening and closing the bottle repeatedly, can cause the release of MPs from the bottleneck and cap areas. Although the inner surface of the bottles did not show significant stress cracks, the frequent use of single-use plastic bottles can increase the chances of MP ingestion.

Safety Assessments

Studies have assessed the safety of reusing polyethylene terephthalate (PET) bottles. One comprehensive assessment exposed PET bottles to various contaminants and found that, even under exaggerated conditions, the remigration of contaminants did not pose a significant public health risk. However, good manufacturing practices are essential to ensure product quality and safety.

Energy and CO2 Savings

From an environmental perspective, reusing PET bottles can lead to substantial energy and CO2 savings. Research indicates that even a single reuse of a 500 ml PET bottle can save about 1 MJ of energy and reduce CO2 emissions by 0.033 kg per bottle. These savings multiply with increased reuse, highlighting the potential for significant environmental benefits.



Is it safe to reuse plastic water bottles?

Jill Bartolotta has answered Unlikely

An expert from Ohio State University in Marine Ecology, Education, Social Sciences, Environmental Science

First I think it important to answer whether or not it is safe to drink from a single-use plastic bottle. The water in a plastic water bottle being used for the first time is already contaminated with plastic and chemicals making your city or well water safer to drink. However, the safety and cleanliness of your city or well water depends on where you live. If you live somewhere that does not take the safety precautions required to provide safe city or well drinking water, then yes, bottled water is your best option. However, much of the water provided through city water or well systems for those living in developed nations is safe to drink and often times safer than drinking from single-use plastic bottles. City water is also more heavily regulated that bottled water. Bottled water is not regulated, at least in the United States, unless the water is bottled in one state and then transported over state lines. If this occurs, then there is one regulation required by the FDA. City water must pass through tens to hundreds of regulations and safety tests before it reaches your tap.

The water inside a single-use plastic water bottled is contaminated in several ways. First, the process required to make and fill water bottles can cause microplastics contamination. A recent study found that all bottled water contained microplastics. Microplastics enter the water in the water bottle in two ways. First, it is known that the water put into bottle water already contains microplastics since microplastics are present in all of our freshwater sources, even the ones used for drinking water. Second, the creation of the bottles and caps leaves microplastics in the air or on the equipment used to make water bottles allowing for a second round of plastic contamination. A study conducted by researchers at the University of New York in Fredonia, and presented by the World Health Organization, found twice as many microplastics in bottled water as they did tap water. But does having plastic in your water make it harmful? The answers for its effect on humans is still unclear, but research conducted on fish and zooplankton (microscopic marine and aquatic animals) has shown plastic ingestion and contamination has effects on the hormones and life cycle patterns of these organisms. The growth, feeding, and reproduction patterns for these organisms is different when they are known to be contaminated with plastic. We still do not have research to prove similar effects on humans, but we do know the chemicals used to make plastic and proven to be leached from plastic, through heat or sunlight exposure, to be endocrine disruptors and carcinogenic.

Next we move to the second method in which bottled water becomes contaminated. Bottled water is already contaminated when it leaves the factory, but then all bottled water is shipped to places for consumer purchase. In transport these bottles are able to heat up since they are not shipped in containers that are kept cold. When plastic heats it releases all the chemicals that are used to make it. As I mentioned earlier we know the chemicals used to make plastic are endocrine disrupting affecting our hormones and other body functions and cancer causing. Therefore, these chemicals leach out of the plastic and into the water you will drink. The more exposure the bottle has to heat the more chemicals released.

Lastly, many people think it is ok to reuse a single-use plastic bottle more than once. Research has shown that this behavior is unsafe. The plastic used to make bottles is very thin and consequently subject to cracking due to a weaker structure. These cracks can harbor bacteria and lead to unsafe drinking water. Washing the bottle in hot water, like your dishwasher, can lead to more cracks and cause the plastic to leach chemicals (Cooper et al., 2011).

In conclusion, as a consumer you must first consider whether it is safer for you to drink bottled water or water from your tap based on where you live. I suggest doing research to better understand the safety regulations required by your local water treatment facility to determine the cleanliness of your water. Then if you choose to use a bottle to refill your water I suggest you use one made of a thick plastic that is not subject to cracking or a metal or glass bottle.


Cooper, J.E., Kendig, E.L., and Belcher, S.M. 2011. “Assessment of Bisphenol A Released from Reusable Plastic, Aluminum and Stainless Steel Water Bottles”. Chemosphere. 85 (6): 943-947. 



Is it safe to reuse plastic water bottles?

Britta Denise Hardesty has answered Likely

An expert from Commonwealth Scientific and Industrial Research Organisation in Biology, Marine Ecology, Ecology, Plant Ecology

Depends on what you mean by ‘safe’. Where is the water coming from, what is the bottle made from, has it been sitting in the sunlight? If I was to buy a plastic water bottle, I would certainly refill and re-use it.


Is it safe to reuse plastic water bottles?

Marek Cuhra has answered Near Certain

An expert from Institute of Marine Research in Toxicology, Marine Ecology

Washing plastic improves the quality of the water which subsequently is filled into it. In 2017 we published a paper on residues in laboratory-plastic. We found that washing actually improved the quality of the water (we had a biological indicator living inside the plastic-encased aqueous environment which was tested). So, drinking water out of a used and washed bottle should be safer than a brand-new bottle (with residues).

Cuhra, M., Bøhn, T. and Cuhra, P., 2017. In plastico: laboratory material newness affects growth and reproduction of Daphnia magna reared in 50-ml polypropylene tubes. Scientific Reports, 7, p.46442.

link to paper here:

(This answer disregards questions of sterility, microbial contamination of re-used waterbottles etc).


Is it safe to reuse plastic water bottles?

Brian Johnston has answered Likely

An expert from University of Wolverhampton in Cell Biology, Biotechnology, Microbiology

You can reuse plastic bottles for personal use with cold water, however once a bottle is damaged it should be put into recycling as plastic particles could detach into your water.


Is it safe to reuse plastic water bottles?

Marek Kowalczuk has answered Unlikely

An expert from Polish Academy of Sciences in Analytical Chemistry

PET deterioration and oligomers formation is not safe


Is it safe to reuse plastic water bottles?

Umar Abdulmutalib has answered Near Certain

An expert from University of Surrey in Environmental Biotechnology, Molecular Biology, Microbiology

Yes, in my opinion it is very much certain to re-use plastic bottles. Newly released plastic bottles might contain more microplastics compared to the used ones, the rate of degradation of this plastic is very slow due to the nature of the polymer as such leaching could be very much negligible. The practice of recycling has been in existence for very long time especially in developing countries and serves as one of the major ways plastics especially the single use bottles are being recycled.


Is it safe to reuse plastic water bottles?

Lindsay  Haake has answered Likely

An expert from Food and Drug Administration USA in Toxicology

Almost all disposable water bottles are made out of polyethylene terephthalate (PET). From a materials standpoint, reusing PET bottles is perfectly safe. However, the only issue would be cleanliness from its previous use.


Is it safe to reuse plastic water bottles?

Rafael Franco has answered Likely

An expert from Universitat de Barcelona in Parkinson’s Disease, Alzheimer’s Disease, Antioxidants, Nutrition, Pharmacology, Asthma, Cell Biology, Biochemistry

I do not see any problen in reusing for some time plastic bottles for water.

Reusing for long times may not be so conven ient due to partial “chemical” degradation of plastic.

For sure I would not reause much those plastic bottles left in cars under the sun as the temperature inside the car would go quite high and then degradation of the plasctic could occur soon.

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