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Introduction For many years, scientists have been warning that Bisphenol-A (see below) and many plasticizers (see below) are toxic. BPA is the primary ingredient of polycarbonate (PC) Containers made of PET |
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| PET Purity / Safety Debunking Urban Legends |
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| Reusing PET | Re-using beverage containers made of PET does not pose a health risk provided the containers are properly sanitized. Though repeatedly and thoroughly debunked, warnings of dire health consequences, resulting from chemicals released from PET bottles, keep circulating in newspaper and television reports, chain E-mail letters, and a variety of green newsletters and Web sites.1 Supposedly, the toxic chemicals are released by PET bottles when the bottles are re-used, heated, or frozen. The chemicals mentioned are: di-(2-ethylhexyl) phthalate, DEHP (see below); di(2-ethylhexyl) adipate, abbreviated DEHA (see below); and diethylhydroxyl amine, also abbreviated DEHA (see below). Di-(2-ethylhexyl) phthalate and di(2-ethylhexyl) adipate are plasticizers used in a wide variety of plastics, but not in PET.2 Diethylhydroxyl amine also has nothing to do with PET. When the authors of the misinformation deem it necessary to cite a reference, they almost always make vague reference to a "2001 University of Idaho Study" and/or a 2003 "Italian Study". The University of Idaho Study is actually a masters thesis in which the student describes an experiment to search for contaminants in other students' drinking water bottles and concludes that DEHA migrates from PET bottles into drinking water.3 However, the experimental design of the study and the analysis of the results were not peer reviewed and in retrospect, the conclusion of the thesis was simply wrong. The Italian Study, looked for the migration of DEHP into water bottled in PET and stored for prolonged periods. The researchers found no migration of DEHP during the first 8 months of storage and an abrupt pulse of migration at about 9 months with no further migration during the next 3 months of their one year experiment.4 No attempt was made to explain these most peculiar results, which by their very nature strongly suggested that a systematic measurement error of some sort occurred about 8 months into their study. Many other researchers have been unable to explain how DEHA or DEHP could possibly migrate from PET bottles; however, they have repeatedly observed that DEHA and DEHP plasticizers are such ubiquitous environmental and laboratory contaminants that it is very difficult to avoid accidental contamination.5 So why to do suppliers of single-serve beverages, packaged in PET, tend to discourage reuse of their bottles? It is because they have concerns relating to sanitization, not the stability and safety PET. Single-serve bottles typically have small openings, so they are not washed effectively in a standard dishwasher. Unless automated bottle washing equipment is available, they must be washed and sanitized by hand. However, a wealth of practical experience indicates that many people are complacent and resort to a simple, quick rinse often with nasty results.6 Drinking from a bottle, any type of bottle, will introduce microorganisms from your mouth and they will multiply in the remaining liquid or on the damp walls of the container. If a drink contains nutrients (e.g., flavor and nutrient enhanced water, juices, sports drinks etc.), microorganism growth will be much more rapid. PET bottles can be safely reused, provided: 1) They are carefully washed and sanitized between fillings; 2) They are handled in a sanitary fashion during re-filling; and 3) Re-filled bottles are treated the way "open bottles" containing a similar liquid should be handled (i.e., refrigerated and/or consumed in a reasonable period of time).2 In general, it makes good sense to pour from a bottle into a cup when drinking, unless the drink is to be consumed in a relatively short period of time. Just to put a final lid on the issue of PET bottle reuse, it is worth noting that health organizations around the world actively recommend the re-use of PET bottles as part of the Solar Disinfection, SODIS, process. 7 Microbiologically unsafe water can be made potable by placing it in single-serve PET bottles and leaving the filled bottles in direct sunlight for a sufficient period of time. UV-A light penetrates the PET and water to kill microorganisms of all types. There is no evidence that toxic chemicals migrate (leach) from the PET. 2,8,9 1 Bottle Royale. Snopes.com (Accessed 05/15/10) 2 PET Safety FAQs National Association for PET Container Resources (NAPCOR) (Accessed 05/15/10) 3 Lilya D. Analysis and risk assessment of organic chemical migration from reused PET plastic bottles. (MScThesis Environmental Engineering). USA, University of Idaho, Environmental Science Program. 2001 4 Biscardi D, et al. Evaluation of the migration of mutagens/carcinogens from PET bottles into mineral water by Tradescantia/micronuclei test, Comet assay on leukocytes, and GC/MS. The Science of The Total Environment. 2003 (Jan 20); vol. 302 (Issues 1-3): pgs 101-108 5 Wegelin M, Schmid P. Migration of organic compounds from PET bottles. International Water and Sanitation Centre, Report Updated 07/23/03 (Accessed 05/15/10) 6 Oliphant JA, Ryan MC, Chu A. Bacterial water quality in the personal water bottles of elementary students. Canadian Journal of Public Health. 2002; vol. 93 (no. 5): pgs 366-367 (Accessed 05/15/10) 7 Wikipedia Solar water disinfection (Accessed 05/15/10) 8 Berg M, Hug S. Water Treatment Technologies in Low Income Water Treatment Technologies in Low Income Regions Lecture: Water Resources and Drinking Water. EAWAG, Swiss Federal Institute for Environmental Science and Technology, Switzerland (Accessed 05/15/10) 9 Wegelin M, et al. Does sunlight change the material and content of polyethylene terephthalate (PET) bottles? Aqua. 2000; vol. 50: pgs. 125-135. (Accessed 05/15/10) |
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| Plasticizers Phthalates DEHP DEHA |
Unlike many other types of plastics, virgin PET does not contain plasticizers.1 Plasticizers are added to make plastics soft or flexible.2 For example, semi-rigid, polyvinyl chloride (PVC or vinyl) plastic typically contains about 10 percent by weight of plasticizers and very soft, polyvinyl chloride tubing may contain as much as 80 percent. Plasticizers migrate out of plastics and they are widely distributed in the environment. Phthalate plasticizers There are three classes of phthalate esters, ortho-, iso-, and tere-, which differ by the relative positions of the two ester groups on the benzene ring. "ortho" refers to the fact that the side chains are adacent to one another on a central benzene ring. The side chains of "iso-" and "tere-" phthalates are further apart on their cental benzene ring. And in chemistry, small differences in structure can have a huge impact on how a chemical reacts. Ortho-phthalate plasticizers are metabolized quite rapidly to mono-esters (i.e., the replacement of a single "R" carbon chain with a hydrogen atom). These mono-esters are toxic and not readily metabolized further. Iso- and tere-phthalates are also metabolised quickly, but to iso- and tere-phthalic acid (i.e., both "R" carbon chains are replaced with hydrogen atoms), which is excreted and does not have the toxicity of the mono-ester metabolite of the ortho-phthalates. Di(2-ethylhexyl) phthalate, DEHP, benzyl butyl phthalate (BBzP), and dibutyl phthalate (DBP) are examples of very popular ortho-phthalate plasticizers used in a wide variety of extremely poplular plastic products (e.g., construction materials, food packaging, children toys, medical devices, cling wrap, plastic tubing . . .). There is reason to believe that ortho-phthalates have been associated an increased risk of cancer, weakening of immune responses, disruption of sexual development, reproductive system damage, and interfering with neurological development.3,4,5,6,7 Industry groups argue that ortho-phthalates are not a significant health risk; however, the US and other countries are slowly beginning to limit the use of ortho-phthalates and manufacturers of plasticized plastics are making major efforts to find ways of preventing the plasticizers from oozing out of their products.8 The US Consumer Product Safety Improvement Act of 2008, which is being appealed to various degrees, states that DEHP, BBzP, and DBP may not be present in children's products and child care articles at concentrations exceeding 0.1 percent.9,10 Additionally, products that are expected to be placed in a child's mouth must not contain more than 0.1 percent of the iso-phthalate plasticizers diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), or di-n-octyl phthalate (DnOP). |
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| Bisphenol-A (BPA) | Bisphenol-A (BPA) has nothing whatever to do with PET. BPA is not used to make PET plastics, nor is it used as a starting material to make any of the materials used in the manufacture of PET. BPA was first synthesized by A.P. Dianin in 1891 and was studied during the 1930s as a possible nonsteroidal estrogen (female hormone), but diethylstilbestrol (DES), a notorious chemical which has been linked to cancer and birth defects, was considered more promising.1,2,3 Over the years BPA has become increasingly important as a component in a wide variety of products such as: 1) Antioxidants in plasticizers for PVC plastics PC is made by polymerizing BPA in the presence of sodium hydroxide (a strong caustic) and phosgene. All manner of food and beverage containers are made from PC, many of them intended for reuse; however, caustic degergents and even hot water can reverse the polymerization of PC to release BPA.5 This is reason for serious concern, because these are the very conditions used to wash and sanitize PC products. Many widely used dish washing detergents and sanitizers, such as sodium hypochlorite (bleach), are caustic. ![]() By and large, recent literature on low-dose effects of BPA split between industry-funded studies that find no significant reasons for concern and publicly funded studies that find plenty of reasons for alarm.7,8 There is a wealth of research demonstrating adverse genetic and endocrine effects at extremely low concentrations effects that may last for many generations.2,8,9,10,11 There is also evidence that exposure to BPA is related to an increased risk of cardiovascular disease, diabetes, liver disease, and asthma.12,13,14 In April of 2008, Health Canada and the United States National Institutes of Health (NIH) issued reports describing BPA as dangerous.14,15,16 The NIH concluded that for the most part people in developed countries have measurable blood, tissue, and urine levels of BPA, levels which exceed the low levels known to cause biological changes in animals. For all of these reasons, businesses are moving to discontinue the use and sales of PC bottles and US and Canadian governmental agencies are considering restrictions on the use of BPA.18-21 On October 18, 2008, the Canadian Government listed BPA as a toxic substance and announced it would immediately proceed with drafting regulations to prohibit the importation, sale and advertising of bottles containing bisphenol-A and limit the amount released into the environment.22 On October 31, 2008, FDA Commissioner Andrew von Eschenbach announced that an FDA-commisioned panel of scientific experts was sharply critical of an earler FDA report claiming that BPA is safe at current levels found in plastic food containers. The panel accused the FDA of relying too heavily on studies funded by the chemical industry and failing to support its conclusion with scientific evidence.23 In May of 2009, manufacturers of cans for beverages and foods and some of their biggest customers, including Coca-Cola, met to devise a strategy to block looming government bans of BPA. The plan appeared to call for hiring a pregnant model to tour the country extoling the virtues of BPA.24 The US Environmental Protection Agency (EPA) added BPA to its chemicals of concern list, finally beginning a process of examining the evironmental impact of BPA.25
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| Additives Antioxidants Slip additives Antimicrobials . . . |
BetterBottle PET carboys and fittings are made without problem additives. Many other plastics that are used to mold bottles and fittings contain additives to protect the polymers during processing and use, as well as to enhance performance. To list a few, there are: antioxidant additives, including UV blocking additives, to prevent parts from degrading; slip additives to prevent parts from sticking together and to molds; nucleating additives to speed production and improve clarity; antifogging additives to make surfaces more wettable; antimicrobial additives; and coloring additives. Depending on the plastic and the additives, there is the potential for the additives to leach into, and/or react with beverages. |
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| Dioxins | There are no Dioxins in PET and none are formed if PET is burned.1,2 There is absolutely no truth to the Internet-circulated rumors that dioxins can be leached from PET bottles when they are frozen. Dioxins are chlorine-containing chemicals and PET contains no chlorine. Dioxins are a group of chemicals, which include 75 different chlorinated molecules of dibenzo-p-dioxin and 135 chlorinated dibenzofurans. Some polychlorinated biphenyls (PCBs) also are referred to as dioxin-like compounds. These substances can be inadvertently produced during the bleaching of pulp and manufacturing of pesticides, like Agent Orange, and other chlorinated aromatics; however, dioxins are also produced by burning of materials containing chlorine. Natural fires and volcanic eruptions were producing dioxins before modern chemistry came along. But, burning large amounts of chlorinated plastics, like polyvinyl chloride (PVC) 1 National Association for PET Container Resources (NAPCOR) Frequently Asked Questions (Accessed 05/15/10) 2 Halden R. Researcher Dispels Myth of Dioxins and Plastic Water Bottles. Johns Hopkins Bloomberg School of Public Health, Public Health News Center, 615 N. Wolfe Street, Baltimore, MD 21205 (Accessed 05/15/10) |
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| Antimony | The leaching of Antimony from PET has been blown out of proportion. Antimony, abreviated Sb, is present in the earth's crust at a concentration of about 0.2-0.5 mg/kg (thousandths of a gram per thousand grams). Antimony is used in plastics, textiles, rubber, adhesives, pigments, paper, vehicle break linings, and many other products. A significant percentage of the antimony in the surface environment comes from the dust generated by the wear of brakes and the incineration of products containing antimony. Concentrations in air and soil tend to be highest in major urban and industrial areas.1 Antimony is often compared to heavy metals such as lead and arsenic; however, it is far less toxic, poorly absorbed, and excreted at modest rates.1,2,3 More needs to be done to understand the dynamics and effects of antimony contamination in the environment; however, antimony is not the greatest threat to the environment or public health.4
Antimony trioxide, one of the most insoluble forms of antimony, is used only as a catalyst in the production of PET. Catalysts are substances that act in minute concentrations to promote chemical reactions by lowering energy barriers for a chemical reaction; they do not become part of the product, except as trace contaminants. Dr. Bill Shotyk, who had been studying antimony in polar snow and ice at concentrations of a few parts per trillion, found traces of antimony in single-serve, PET bottled water and concluded that it was not advisable to use PET containers to store his samples. Dr. Shotyk examined 12 brands of natural waters from Canada and three brands of deionized water and determined that they contained 156+/- 86 parts per trillion (ppt) Sb and 162+/- 30 ppt Sb respectively.5 The news media, not always the most reliable group of scientific journals, picked up on what Dr. Shotyk reported and attached attention-grabbing headlines.
2 Veesnstra GE, Deyo J, and Penman M. The Oral Toxicity and Mutagenicity of Antimony Trioxide. Toxicology Letters 1998 vol. 95, sup. 1; page 136. 3 Oorts K and Smolders E. Ecological Threshold Concentrations for Antimony in Water and Soil. Environ. Chem. 2009 vol. 6(2);116-121. (Accessed 05/15/10) 4 Maher WA. Antimony in the environment new global puzzle. Environ. Chem. 2009 vol. 6; pgs. 93-94. (Accessed 05/15/10) 5 Shotyk W, Krachler M, Chen B. Contamination of Canadian and European bottled waters with antimony from PET containers. J Environ Monit. 2006; vol.8: pgs. 288-292 (Accessed 05/15/10) 6 Westerhoff P et al. Antimony leaching from polyethylene terephthalate (PET) plastic used for bottled drinking water. Water Research: 2008 Volume 42, Issue 3, Pages 551-556 (Accessed 05/15/10) 7 Keresztes et al. Leaching of antimony from polyethylene terephthalate (PET) bottles into mineral water. Science of The Total Environment: Volume 407, Issue 16, 1 Pages 4731-4735, August 2009 8 Antimony in drinking-water. Background document for preparation of WHO Guidelines for drinking-water quality 2003). Geneva, World Health Organization (WHO/SDE/WSH/03.04/74). (Accessed 05/15/10) 9 Ground Water & Drinking Water: Consumer Factsheet on: ANTIMONY. United States Environmental Protection Agency (EPA); November 28th, 2006 (Accessed 05/15/10) 10 Technology Transfer Network - Air Toxics Web Site: Antimony Compounds (7440-36-0). United States Environmental Protection Agency (EPA); November 6th, 2007 (Accessed 05/15/10) 11 Water Quality and Health - Antimony: Exposure. Health Canada. Date Modified: 2008-01-07 (Accessed 05/15/10) |
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PET and our Planet Debunking Urban Legends |
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| Is Glass Greener? | Glass is not better for the environment than PET. Various authorities, such as the National Geographic Green Guide have repeated a claim that appears to have been made first by Sheela.R.Chunkath, a writer for The Hindu (July of 2001), “Producing a 500 ml PET bottle generates more than 100 times the toxic emissions to air and water than making the same size bottle out of glass.”1,2 This statement is wildly incorrect. It takes between 43.6-99.2 MJ (12.1- 27.5 Kilowatt hours) to make a 6 gallon (22.7 L), 24 pounds (10.9 Kg) glass carboy, depending on the scale and efficiency of the glass plant producing it, and only 25.1 MJ (7 Kilowatt hours) to make a 6 gallon (22.7 L), 1.5 pounds (0.68 Kg) BetterBottle carboy.3,4 This means that the glass carboys require 173%-395% more energy to produce than the BetterBottle carboy. Moreover, the extra energy cost of glass does not stop with production: 1) Glass carboys require 16 times more energy to transport than BetterBottle carboys; 2) Glass carboys require 2-3 times more packaging to protect them during shipment; and 3) The energy saving for reheating recycled glass is only about 40%, with the result that in many markets recycled glass is hardly worth sorting, grinding, and transporting ($20-$40/ton). Very few municipal recycling services will pick up large glass carboys. In Florida, recycled glass is being turned back into sand for beaches.5 1 Chunkath, S.R. Hazardous Hues: Plastic vs. Glass. The Hindu, July of 2001 (Accessed 05//15/10) 2 Plastic Containers The Backstory. National Geographic: Green Guide (Accessed 05/15/10) 3 Gerngross. T.U. and Slater, S.C. How Green are Green Plastics? Scientific American Aug 2000. (Accessed 05/15/10) 4 Benefits of Recycling to the Glass Manufacturer (Special focus on UK). GlassTec Topic of the Month April 2008 (Accessed 05/15/10) 5 Costello, P.J. Saving Florida’s Bikinis. RecyclingBizz.Com, 09/12/07 (Accessed 05/15/10) |
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