Recently we taught a class on emergency water storage and disinfection at a preparedness expo. We love interacting with our students and one gentleman brought up an issue with PET containers suggesting recent studies had found them unsafe for emergency water storage. True to our nature, we just had to research and find out the truth about the safety of PET bottles. That search resulted in this article.
The PETE Bottle Safety Debate
Kylene and Jonathan Jones
Chatter in the prepper circles is speculating about the dangerous chemicals leaching into water storage from plastic containers. Word on the street is that PET bottles are not safe for water storage. Fact or fiction? Let’s take a closer look at the research.
First, let us establish a foundational understanding of the various forms of plastics and how they are used for storing food products. This information was obtained from a Smart Plastic Guide published by Sea Studios Foundation.1 On the bottom of most plastic bottles there is a recycling symbol that identifies the type of resin used in the production. Some plastics have potential health risks and should not be used to store food products, while others appear to be safe.
Plastic #1 – Polyethylene Terephthalate (PET)
There are no known health issues with this plastic. PET is used to produce bottles for soft drinks, water, beverages, peanut butter and other food containers.
Plastic #2 – High Density Polyethylene (HDPE)
There are no known heal issues with this plastic. HDPE is used for foods such as milk and water jugs in addition to make containers for a host of non-food items.
Plastic #3 – Polyvinyl Chloride (PVC or V)
Harmful chemicals are produced in the manufacturing, disposal or destruction of PVC including: lead, di(2ethylhexyl)adipate (DEHA), dioxins, ethylene dichloride, and vinyl chloride.1 This plastic is used for clear food packaging, cling wrap, squeeze bottles, cooking oil bottles, peanut butter jars, and many non-food plastic items.
Plastic #4 – Low Density Polyethylene (LDPE)
There are no known health issues. This plastic is used to produce bags for bread, frozen food bags and grocery bags. Most plastic wraps are made from LDPE and some bottles. Some organic pollutants are formed during manufacturing.
Plastic #5 – Polypropylene (PP)
No known health issues are associated with PP. It is used to make containers for deli soups, syrups, yogurt and margarine containers, baby bottles, straws, and many non-food items.
Plastic #6 – Polystyrene (PS)
Styrene can leach from polystyrene and be absorbed by food. It is stored in body fat and over the long term, acts as a neurotoxin. Repeated exposure may be dangerous. Formed polystyrene is also known as Styrofoam and is used to produce food containers, egg cartons and other packaging.
Plastic #7 – Mixed (Other)
Health effects vary with the resin and plasticizers. Polycarbonate plastic leaches BPA which is a known endocrine disruptor.
Sea Studios recommends that only plastic containers with the recycling #1, #2, #4 and #5 be used for food storage. When practical they recommend using glass containers. They are a safer alternative as glass will not leach chemicals into the food.
Now with that foundation, let’s explore the PET controversy. Is it safe to store food and water in PET containers for emergency preparedness? Are dangerous chemicals leaching into my water storage from the plastic?
One chemical of concern is antimony (Sb), a metal found in natural deposits. It is present in low levels in the environment. Antimony is found in food, drinking water and in the air. The short-term health of effects of high exposure levels may include gastrointestinal disorders, nausea, vomiting and diarrhea.2 According to the EPA, exposure of antimony in drinking water above the maximum contaminant level (MCL) for many years may result in increases in blood cholesterol and a decrease in blood sugar. The EPA established MCL for antimony is 0.006mg/l or 6ppb (6000 ng/l).3
A study from 2005 entitled, Contamination of Canadian and European bottled waters with antimony from PET containers, found evidence that some leaching of antimony does occur from PET bottles.
“The data presented here leave little doubt that bottled waters stored in PET are contaminated with Sb from their containers. … We wish to emphasize that all of the waters measured in our lab to date were found to contain Sb in concentrations well below the guidelines commonly recommended for drinking water…”6
In response to two European studies that found evidence of estrogenic activity in mineral water bottled in PETE plastic, Julia R. Barrett published an article in Environmental Health Perspectives in June 2009. She concludes:
Neither of the European studies can be used to deduce anything about potential human health effects of drinking PET−bottled beverages.5
In addition she includes the following quote in her article:
“It has been demonstrated through extensive studies that PET meets all established safety standards for use in food and beverage packaging and has been safely used for that purpose for decades,” says Ralph Vasami, executive director of PETRA. The organization also emphasizes that PET destined for food and beverage containers does not contain bisphenol A or orthophthalates, both of which have been heavily scrutinized as endocrine disruptors.
The studies report that length of storage and heat may impact the amount of chemicals that leach into water and food products. A study published in the Journal of Environmental Monitoring (Issue 4, 2012), states, “Bottle aging and increase in bottle volume were associated with decreased migration of antimony from bottles.”9 If aging of bottles decreases the migration of antimony into the water there might be a case made for rotating water more frequently when water storage containers are new.
What about using PET bottles for solar water disinfection? In response to the concern, scientists at SODIS.ch published this document.
Reports from around the world regarding substances in PET bottles that cause cancer are worrying users of the SODIS method. Therefore, a number of research institutions tested the scientific accuracy of these reports and carried out their own analyses of the materials. Studies have been produced for the following substances: antimony, adipates, phthalates, acetaldehydes and formaldehydes. These studies show that when the SODIS method is applied correctly with PET bottles, there is no danger to human health.
Antimony speeds up chemical processes in the manufacture of PET (catalyst). However, antimony does not get into the water unless the bottles are stored for a very long time or heated to very high temperatures. The storage times and temperatures in question far exceed those that are involved in the correct application of the SODIS method. There is therefore no danger to the health of SODIS users.
Adipates and phthalates
Adipates and phthalates are used as softeners in the production of certain types of plastics and packaging materials (e.g. PVC). Adding these substances to the plastic makes it more flexible and easier to work. Although these softeners are not particularly toxic, they do represent a threat to health if they are consumed in large quantities. However, softeners are not needed in the production of PET. If softeners are found in the water from PET bottles, they must have been in the water before the bottles were filled.
Aldehydes are formed when the plastic is heated in the manufacturing process for PET bottles. A research group in Eawag, the Swiss Federal Institute of Aquatic Science and Technology, therefore researched the questions of whether formaldehydes and acetaldehydes are transferred from the PET bottles to the water when the SODIS method is applied, and if so, in what quantities. It was found that exposure to the sun has no effect on the concentration of acetaldehydes, though the concentration of formaldehydes does increase with the length of exposure. However the concentrations of aliphatic aldehydes remained far below the state regulatory limit for drinking water in all samples. Therefore, the SODIS method does not pose a health risk.7
According to research presented above, solar water disinfection preformed in PET bottles is safe as long as it is done correctly. One final study published in Food Additives and Contaminants: Part A Volume 28, Issue 1, 2011 reaches the following conclusion:
It was concluded that antimony levels in beverages due to migration from PET bottles manufactured according to the state of the art can never reach or exceed the European-specific migration limit of 40 microg kg(-1). Maximum migration levels caused by room-temperature storage even after 3 years will never be essentially higher than 2.5 microg kg(-1) and in any case will be below the European limit of 5 microg kg(-1) for drinking water. The results of this study confirm that the exposure of the consumer by antimony migration from PET bottles into beverages and even into edible oils reaches approximately 1% of the current tolerable daily intake (TDI) established by World Health Organisation (WHO). Having substantiated such low antimony levels in PET-bottled beverages, the often addressed question on oestrogenic effects caused by antimony from PET bottles appears to be groundless.8
We have found no evidence in our research that make us uncomfortable storing water for our family in PET bottles. However, if you are concerned about the levels of any chemical in your water, filter it before consuming with a filter that is rated to remove the substance you are concerned about. Coagulation/filtration and reverse osmosis are effective methods for removing antimony from water.
Water storage is a critical element of emergency preparedness. We cannot stress enough the importance of storing water. The risk of contracting nasty water-water borne illness from drinking water from a contaminated water source, or dehydration from lack of water, is far greater than the risk of anything that might possibly have leached into your stored water from food grade plastic containers. We encourage you to continue to store as much water as you reasonably can as part of your preparations.
Fact or fiction? We’ve done the research and are highly confident that PET bottles are safe for our family to use for emergency preparedness. Clean, used soda and juice bottles are cheap and plentiful making emergency water storage possible for everyone, regardless of financial resources. We invite you to explore the evidence and decide for yourself.
Kylene and Jonathan Jones are the authors of The Provident Prepper—A Common-Sense Guide to Preparing for Emergencies. Visit them online at www.TheProvidentPrepper.org and www.YourFamilyArk.org.
Copyright Your Family Ark LLC 2014 – This article may be reproduced in its entirety with appropriate author credits and working links back to the original post and source documentation.