Home :: Myths & Realities

MYTH: Reusing plastic water bottles can cause them to break down into carcinogenic compounds.

Reality: False.

This bit of plastic bottle scare lore is based upon a master's thesis from a University of Idaho graduate student, one which was unfortunately reported upon by the media despite its lack of peer review. According to The International
Bottled Water Association (IBWA):

The US Food and Drug Administration (FDA) regulates bottled water as a packaged food product and, for bottled water and all other foods and their packaging, FDA has determined that PET meets standards for food contact materials.

The basis for [the e-mail was] a college student's masters thesis that was not subject to peer review and did not reflect a level of scientific rigor that would provide accurate and reliable information about the safety of these products. Fortunately, FDA requires a much higher standard to make decisions about food contact packaging. DEHA, as mentioned in the email is neither regulated nor classified as a human carcinogen. Further, DEHA is not inherent in PET plastic as raw material, byproduct or decomposition product. DEHA has been cleared by FDA for food contact applications and would not pose a health risk even if present. DEHA is a common plasticizer used in many plastic items, many of which are found in the lab setting. For
this reason, the student's detection (see comment above) is likely to have been the result of inadvertent lab contamination.

Also note that PET plastics used for bottled water containers are not unique to this product type and is the same as PET plastics used to package other common foods and beverages.

(No “diethylhexyl adipate” (DEHA) is used in PET manufacturing. For details pl. refer Pl. refer FAQ of this note.)

The Environmental Protection Agency (EPA) at one time included DEHA on the list of toxic chemicals maintained under the federal Emergency Planning and Community Right-to-Know Act (EPCRA), but they have since removed it from the list because DEHA "cannot reasonably be anticipated to cause cancer, teratogenic effects, immunotoxicity, neurotoxicity, gene mutations, liver, kidney, reproductive, or developmental toxicity or other serious or irreversible chronic health effects." And, according to the International Agency for Research on Cancer (IARC), diethylhexyl adipate "is not classifiable as to its carcinogenicity to humans."

Some organizations (including the IBWA) do recommend that plastic water bottles be used only once before recycling, but not because re-use is likely to cause carcinogenic compounds to leach
from the plastic bottles into the liquids they hold. The concern is that people (particularly children) can too easily spread and ingest bacteria from their hands and mouths by re-using bottles
without properly washing them or allowing them sufficient time to dry.

FREQUENTLY ASKED QUESTIONS (FAQ) on PET

Will a plastic bottle leach harmful substances into water if I reuse it?

Most convenience-size beverage bottles sold in the U.S. are made from polyethylene terephthalate (PET). The FDA has determined that PET meets standards for food-contact materials established by federal regulations and therefore permits the use of PET in food and beverage packaging for both single use and repeated use. FDA has evaluated test data that simulate long-term storage and that support repeated use.

The toxicological properties of PET and any compounds that might migrate under test conditions have also been well studied. The results of these tests demonstrate that PET is safe for its intended uses. (For details, see The Safety of Polyethylene Terephthalate.)
What about the student project that claimed to have found unhealthy compounds in water samples from reused bottles?

What about the student project that claimed to have found unhealthy compounds in water samples from reused bottles?

The subject of a widely circulated e-mail hoax, these claims stem from a University of Idaho student’s masters thesis that was promoted in the media but was not subject to peer review, FDA review or published in a scientific or technical journal.

While the student project may have been suitable work for a masters thesis, it did not reflect a level of scientific rigor that would provide accurate and reliable information about the safety of these products. Fortunately for consumers, FDA requires a much higher standard to make decisions about the safety of food contact packaging.

But I read that the student’s project found carcinogens?
The student’s thesis incorrectly identifies di(2-ethylhexyl) adipate (DEHA), a plastics additive, as a human carcinogen. DEHA is neither regulated nor classified as a human carcinogen by the U.S. Occupational Safety & Health Administration, the National Toxicology Program or the International Agency for Research on
Cancer, the leading authorities on carcinogenic substances.

In 1991, on the basis of very limited data, the U.S. Environmental Protection Agency classified DEHA as a "possible human carcinogen." However, in 1995, EPA again evaluated the science and concluded that "...overall, the evidence is too limited to establish that DEHA is likely to cause cancer."

Further, DEHA is not inherent in PET as a raw material, byproduct or decomposition product. DEHA is a common plasticizer that is used in innumerable plastic items, many of which are found in the laboratory. For this reason, the student’s detection of DEHA is likely to have been the result of inadvertent lab contamination. This is supported by the fact that DEHA was detected infrequently (approximately 6% of the samples) and randomly, meaning that the frequency of detection bore no relationship to the test conditions.

Moreover, DEHA has been cleared by FDA for food-contact applications and would not pose a health risk even if it were present.

Finally, in June 2003, the Swiss Federal Laboratories for Materials Testing and Research conducted a scientific study of migration in new and reused plastic water bottles from three countries. The Swiss study did not find DEHA at concentrations significantly above the background levels detected in distilled water, indicating
DEHA was unlikely to have migrated from the bottles. The study concluded that the levels of DEHA were distinctly below the World Health Organization guidelines for safe drinking water.

Is it true that the U.S. Food and Drug Administration (FDA) only allows plastic beverage bottles, such as those made with polyethylene terephthalate (PET), for one-time use?

No, FDA allows PET to be used in food-contact applications, including food and beverage packaging, regardless of whether the packaging is intended for single or repeated use. PET beverage bottles sold in the United States are designed for single use for economic and cultural reasons, not because of any safety concerns with PET.

In fact, refillable bottles made with the same PET resin as single-use bottles are safely reused in a number of other countries. The only difference is that refillable bottles have thicker sidewalls to enable them to withstand the mechanical forces involved with industrial collection and commercial cleaning and refilling operations.

Can freezing a PET beverage bottle cause dioxins to leach into its contents?

This is the subject of another e-mail hoax. There simply is no scientific basis to support the claim that PET bottles will release dioxin when frozen. Dioxins are a family of chemical compounds that are produced by combustion at extremely high temperatures. They can only be formed at temperatures well above 700 degrees
Fahrenheit; they cannot be formed at room temperature or in freezing temperatures. Moreover, there is no reasonable scientific basis for expecting dioxins to be present in plastic food or beverage containers in the first place.

Compiled by :
PET Marketing Technical Services

Phone: 022 –3032 22012 / 2251 / 2252

Source: http://www.plasticsinfo.org/beveragebottles/faq.html

POINT: Plastics / plastic bags are harmful to plants & the soil

Counter Point:

• Plastics protect plant life in multiple ways
• Plastics prevent massive deforestation by offering wood substitutes. eg. Furniture, building materials, crates
• Plastic pipes are used extensively in Irrigation & Water Management
• Flood Irrigation, Sprinkler Irrigation, Micro Irrigation (Drip/Trickle) etc

China uses One million tonnes of PE in agricultural application.

POINT: Plastics are not recyclable

Counter Point: Plastics are 100% recyclable via various routes :

• Mechanical recycling : Plastics can be recycled several times into economically useful low cost products eg. Footwear, mats, sewer pipes etc.,
• Waste plastics are also recycled without sorting into synthetic lumber / wood products like rails, fencings, posts, benches and land scaping products.
• Plastics can be thermally recycled / incinerated to recover energy
• Plastics can be chemically recycled to recover monomer for reuse.

In India we already recycle 60% of plastics from both Industry and urban waste streams Vs world average of 20-25%.

POINT: Plastics deplete precious & scarce fossil fuel

Counter Point: The different uses of commercially produced oil.

Plastics use globally only 4% of commercially produced oil. The rest being accounted by transport, energy and others. Infact plastics add value and extend life of fossil fuel instead of burning it directly.

POINT: Plastics are toxic and are not safe for usage

Counter Point: Plastics are used worldover safely for personal care products, packaging of food & medicine, in-vitro medical applications and for child care products.

• Toothbrush, toothpaste tubes, shampoo bottle
• Milk pouch, edible oil container, ice cream pack
• Blister packing - tablets and capsules
• Medical disposables - IV bags, blood bags, gloves
• Heart valve, hip joint
• Toys, diapers

Food and drugs authorities worldwide permit use of different plastics in various applications. Industry needs to adhere to prescribed standards.

POINT: Plastic bags contain plasticizers

Counter Point:

• Plastic bags are made from Polyethylene (PE) which is a polymer of pure Carbon & Hydrogen. The material by itself is soft in nature. No plasticizers are used / required for any Polyethylene application including Poly Bags.
• The campaign that Plastic bags contain plasticizers is a malicious canard
• Plasticizers are used only in PVC Products.

POINT: Plastic bags contain titanium dioxide and lead based components which are toxic & Dyes used in coloured bags cause severe health hazards.

Counter Point:

• Most of the pigments used for making bags are organic in nature. Use of lead or cadmium based compounds does not arise at all.
• The inorganic pigments used in plastics do not contain lead or cadmium.
• Organic pigments which are used are compatable with the polymer to get bonded. They cannot leach out.

Industry has accepted to use natural unpigmented carry bags for food contact applications. Recycled bags will be coloured (using BIS approved pigments) for other applications.

Next »