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Learn to read the signs on plastic containers

Criada em: 2 junho de, 2015
Summer’s severe temperatures are upon us and every time you reach out for your plastic bottle of water, it would help to keep a few facts in mind.

First, learn to decode the symbol on the bottle that represents the kind of plastic it is.

The coding symbol consists of arrows that cycle clockwise to form a triangle enclosing a number with an acronym below, Gundeep Singh, President and Founder of The Change Initiative, said. This is a clue to the kind of plastic the bottle is made of and the coding is used by the Society of Plastics Industry (SPI).

Second, depending on the kind of plastic, exposure to severe heat can lead to a reaction of the plastic with its contents. Nadine Aoun, specialist nutritionist, said that though Bisphenol A, a substance found in plastics, has not been proven to leak in water under normal conditions, a reaction can occur under severe temperature changes.

Since plastic is not normally biodegradable, recycling it is part of global efforts to reduce plastic in the waste stream and the Society of the Plastics Industry Identification coding system is placed to identify the type of polymer or resin the plastic is composed of, Singh said.

He clarified that the number in the middle does not indicate how hard it is to recycle an item nor does it specify the amount of times the plastic was recycled. The number, he said, is merely an assigned number that identifies the specific type of plastic container.

“Polythene terephthalate plastic items are marked with resin code 1, and typically bear the letters PET or PETE. Plastic soft drink, water and juice bottles are the most common items made from PET,” said Singh.

When recycled, plastics with the resin code 1 are typically turned into new packaging or used in textiles and carpeting. As for products marked with the resin code 2, those are made from high-density polythene, bearing the acronym HDPE, commonly used for milk and water jugs.

“Polyvinyl chloride (PVC), indicated by resin code 3, is used in vegetable oil bottles, plumbing pipes, wire coating and detergent bottles,” Singh said.

In instances where plastics have been mixed, the plastic container is marked with a resin code 7 which may contain Bisphenol A, a substance the National Institute of Environmental Health Sciences believes can cause health implications on foetuses, infants and children. Effects on the brain and nervous systems can occur.

“It is probably wise for pregnant women and children to avoid these containers,” he said.

Health factors

Aoun explained that reusing single-use plastic bottles, with the acronym PET, can result in the leaking of phthalates into the liquid contained. Phthalates are the chemicals used in plastic to add flexibility.

“Most concern has centred around the phthalate DEHP or BEHP, which has been shown to cause women to give birth to boys with smaller genitalia and undescended testes, and DEHA, which may be a carcinogen and is known to cause liver problems,” she said.

As for polycarbonate (PC) plastics, a common chemical used is Bisphenol A (BPA), which, as Singh mentioned, is not recommended for children and pregnant women.

“Most of the research on BPA effects has been linked to certain types of cancer, lowered levels of testosterone and other ill effects,” said Aoun. “According to some researchers, BPA exposure [even in very low doses] has also been linked to obesity, attention deficits, lowered sperm counts and early puberty onset.”

Plastic bottles used for water typically contain Bisphenol A which is linked to hormone interference and obesity, in addition to neurological disorders in children and several types of cancer.

“Research found a substantial correlation between exposure to very high temperatures and the rate of BPA release. For your own safety, don’t leave your water bottle in the car where the sun’s heat can cause this reaction,” she said.

Aoun also clarified that water bottles should be treated just as any other food product for optimum safety. She said that exposure to room temperature for an extended period of time can make a water bottle the breeding ground for bacteria.

“Plastic water bottles, even those labelled for one-time use (PET) as mentioned above, can be reasonably (two-three times) reused with proper cleaning between each use,” Aoun said.

Recycling programmes in the UAE

In the UAE, there are companies responsible for the recovery and segregation of plastics and other companies involved in producing granules from waste plastic to be used as ‘down cycled’ products. Singh explained that these granules or particles are used to produce trash bags, plastic bags stretch film and plastic furniture or bins.

Although recycling is being practised and encouraged across the country, he said that resources and awareness remain fairly limited in relation to the high amount of plastic produced in the region. Singh also revealed that the average plastic used in water bottles is almost 30 per cent more than that used in Europe.

“Recycling plastics can lead to products that are most often of a lower grade than the ones previously produced,” Singh said. “In that regard, products that are down cycled are useful but tend to be more hazardous than the original use product.

“The primary purpose of the codes is to allow efficient separation of different polymer types for recycling. Separation must be efficient because the plastics must be recycled separately because one item of the wrong resin can ruin a mix,” clarified Singh.

“We must find ways to reduce the influx of plastics in the UAE as well as find pragmatic ways to reduce and manage plastic waste,” he said.

In some cases, algae and enzymes in nature play a role but, in most cases, plastics have a life of a few hundred years or more, causing them to be highly unlikely to degrade in nature. Consequently, the process of recycling plastic is crucial in order to recover and reprocess waste plastic into useful products that can be completely different in form from their original state.

INFOGRAPHIC

Efficient recycling codes