Fact or fiction: reusing plastic water bottles is harmful to your health

It's Plastic Free July, a month during which resources and ideas to help you (and millions of others around the world) reduce single-use plastic waste everyday are disseminated to over 120-million participants in 177 countries.

We've long been warned about the dangers of reusing plastic bottles for health, but are simultaneously being told that we should reduce our use of single-use plastics, leaving us wondering how to win the battle against single-use plastics without putting our health at risk.

Four experts were asked the question: "Is reusing plastic bottles harmful to my health?" This is how they responded:

LORINDA VAN DYK

Cansa Seal of Recognition co-ordinator

The reuse of plastic water bottles can be harmful to your health as re-using plastic bottles intended for one single use can increase the risk of the plastics leaching chemicals and being contaminated with bacteria.

Chemicals of concern include dioxin, bisphenol A (BPA) and phthalates, which are classified as endocrine disruptors. These are chemicals that may interfere with the body's hormone levels and have been linked to adverse developmental, reproductive, neurological and immune effects as well as some hormone-related cancers, such as breast and prostate cancer.

For consumers it is important to note that a safer choice can be made by looking into the recycling codes (see below) imprinted under the plastic bottles before buying them. In general, plastics with the recycling codes 1, 2, 4 and 5 are scientifically considered safer than the plastics with recycling codes 3, 6 and 7.

To lower one's risk of cancer and other adverse health effects, I recommend that consumers lower their use and exposure to plastics in general and to rather opt for similar products made from glass.

They can also lower their risk by choosing BPA-free options or by looking for our Cansa Seal of Recognition on products that have been evaluated and found to be free of all known cancer-causing substances.

CHARLOTTE METCALF

Executive director of the South African National Bottled Water Association (SANBWA)

PET (polyethylene terephthalate) is approved as safe for food and beverage contact by the FDA and similar regulatory agencies throughout the world, and has been for over 33 years.

The idea that plastic can leach into bottled water is incorrect, and is a popular urban myth that has been debunked by many credible scientific sources in recent years.

This "leach" issue stems from a concern about phthalates and BPA. BPA is not used to make PET, nor is it used to make any of the component materials used to make PET.

There are no substances known that can migrate from PET that could be responsible for the endocrine disruptors (substances having a hormonal effect) identified in a study usually referred to as the "Goethe Study".

PET does contain antimony oxide, which is used as a catalyst. But the amounts are well below the established safe limits for food and water set by the World Health Organisation. 

DR NATALIE ANECK-HAHN

Director of the Environmental Chemical Pollution and Health Research Unit at the University of Pretoria

Simply put, PET plastic bottles are single-use or disposable bottles and should be recycled after use.

Reusing them can cause chemicals to leach from the plastic into the beverage or fresh water that you have put into the bottle, especially if the bottle is scratched or exposed to high temperatures (leaving it in the car in the middle of summer, for example). Some of these chemicals have been associated with health effects.

PET bottles may contain chemicals, called non-intentionally added substances, which may get added due to the manufacturing process, which can leach into the water.

It is important to remember that we are exposed to multiple chemical mixtures daily and therefore we have mixture effects. This means that even though these individual chemicals are present in low amounts that should not cause effects, collectively they may exert an effect, which results in an adverse health effect.

It is better to be plastic-wise, make sure you know your numbers [recycling codes - see image above] and read the labels and make sure the bottle is BPA free or invest in a stainless steel or glass bottle.

CHERI SCHOLTZ

CEO of the PET Plastic Recycling Company

PET bottles are 100% recyclable and can be used over and over again. They are not "single-use" bottles, are not trash and are safe to use.

There has been a lot of confusion about what is in our plastic containers since concerns were raised about the safety of polycarbonate products containing BPA.

There is no connection between PET plastic and BPA. BPA is not used in the production of PET material, nor is it used as a chemical building block for any of the materials used in the manufacture of PET.

PET bottles are safe for use and reuse so long as they are washed properly with detergent and a little water to remove bacteria, as you would any other container.

Editor's note: a previous version of this story included an example of the amount of antimony oxide that can safely be consumed.