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Plastic bottles are not poisonous
by:
11/6/2003 4:18:00 PM
There is no truth in the rumour being spread via the internet that reusing disposable plastic bottles causes poisoning.
This is according to Prof Olof Vorster, head of the department of polymer technology, who says it is yet another one of those urban legends that are so popular with environmen-talists.
The message being populated on the internet reads as follows:
"Many are unaware of poisoning caused by reusing plastic bottles. Some of you may be in the habit of using and reusing your disposable mineral water bottles (eg Evian, Aqua, Ice Mountain, Vita), keeping them in your car or at work. Not a good idea.
In a nutshell, the plastic (called polyethy-lene terephthalate or PET) used in these bottles contains a potentially carcinogenic element (something called diethylhydroxylamine or DEHA).
The bottles are safe for one-time use only. If you must keep them longer, it should be for no more than a few days, a week max, and keep them away from heat as well.
Repeated washing and rinsing can cause the plastic to break down and the carcinogens (cancer-causing chemical agents) can leach into the water that you are drinking. Better to invest in water bottles that are really meant for multiple usage. This is not something we should be scrimping on. To those of you with family, please advise them, especially children."
Prof Olof explains that the rumour has its origin in a masters thesis by D Lilya of the University of Idaho. In that thesis, the student incorrectly identifies di(2-ethylhexyl) adipate used in PET bottles as DEHA (diethylhydroxylamine). "The latter was originally reported to be potentially carcino-genic, but that report has since been rectified by the environmental protection agency."
To curb more rumours of spreading, the plastics federation of South Africa has now set out some guidelines to put everyones minds at ease.
It states that the US food and drug admini-stration (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.
Furthermore DEHA (Di-ethyl hydroxyl amine) is not found in PET or in the production of such bottles. DEHA (di-2-ethyl-hexyl-adipate), also called DOA, is a common plasticiser used in soft, flexible vinyl polymers. A study of water bottles by the University of Calgary, found bacteria in elementary school childrens bottles. It was reported as being DEHA, but the wrong type. DEHA, or DOA, is among the organic contaminants found in drinking water with the highest concentration. During summer, or after being left in a hot car, the heat causes the bacteria to grow faster and higher levels could be detected.
The plasticiser is used for vinyl polymers and is an organic contaminant in just about all drinking water. It is not used in PET bottles and people are worrying unnecessarily. People who reuse such a bottle to carry drinking water are in no danger of chemicals leaching from the plastic into the water.
It is recommended that plastic water bottles be used only once before recycling, but not because reuse 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 easily spread and ingest bacteria from their hands and mouths by sharing and reusing bottles without properly washing them or allowing them sufficient drying time.
If you can smell or taste the plastic in a bottle, you are due for a new one so toss it in the bin and replace it. The main threat to your health is from not rinsing or washing them carefully to ensure basic hygiene.
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