Plastic is not the harmless compound that it once appeared to be. It does not degrade readily, and is one of the most durable pollutants on earth. Over hundreds of years, plastic disintegrates into smaller and smaller pieces of plastic which eventually enter the food chain, unchanged. In 2005, 28 million tons of plastic waste were produced in the US alone. The Great Pacific Garbage Patch is an example of what happens to all our plastic cups, bottles and bags – it is a stretch of plastic waste several million square kilometers in size. It is not just the environment that suffers. Plastic releases chemicals when scratched and heated, or when it comes in contact with acidic substances. One of these chemicals is Bisphenol A (BPA), an important component of plastic water bottles, baby bottles, inner lining of food cans, microwave containers, and hundreds of common household and industrial products. The use of BPA-containing plastic in the packaging of food and beverages is alarming because there is a long list of health disorders attributed to the chemical.
BPA is a chemical compound that has a structure similar to the hormone estrogen. It sets off a chain reaction of estrogen responses in the male and female body, such as breast cell growth, regulation of the menstrual cycle, and a wide range of normal body development and functions. BPA upsets the balance of hormonal messages in the body. Hundreds of scientific studies have shown that BPA is linked to developmental and reproductive abnormalities, cancer, and even neurological disorders in animal models. In humans, the compound has been found to be linked to early onset of puberty, breast, uterine and prostate cancer, obesity and diabetes. By far the most common finding is that BPA in low doses is toxic during fetal and infant development. Pregnant women who were exposed to BPA had a higher than normal rate of birth defects and fetal and neonatal deaths.
Although BPA is only lethal at very high doses, increasing scientific evidence suggests that it can disrupt key body functions at very low doses, and builds up in our bodies over time with each exposure. Despite the multiple scientific studies that clearly link BPA to developmental and other abnormalities in animals and humans, the US Food and Drug Administration (FDA) issued a statement on August 15, 2008 reaffirming the safety of products containing low levels of BPA. However, no mention is made of the effects of repeated exposure over many years, or of the effect of combinations of hormones and BPA.
There are billions of people around the world who drink water from plastic bottles every day. Unfortunately, bottled water is harmful to the environment, your wallet and your health. Ironically, people who buy bottled water in an effort to improve overall well-being are actually putting their health at risk. BPA and other toxic chemicals have been shown to leach out of both single-use and reusable plastic water bottles. Repeated use of plastic bottles has been shown to increase the rate of chemicals like BPA leaching out, especially bottles intended for single use.
By far, the most common types of water bottles in use today are the single use and re-usable plastic bottles such as Aquafina and Nalgene. Examining the recycling labels on the base of the bottle can help determine which bottles to avoid altogether. Bottles marked with “#1” should only be used once. Bottles marked “#7”, also called Lexan, should be avoided altogether, as they definitely release BPA into the liquid. Bottles marked “#3” can also release BPA. Types 2, 4, 5 and 6 are the safer choices. However, it is safest to avoid plastic bottles altogether.
The only water bottles that are 100% safe to use are made of glass, but since glass is breakable and rather heavy, it does not appear to be a practical alternative. Fortunately, other types of water bottles are available. One common alternative is the Sigg brand of water bottle, made from aluminum with a water-based epoxy inner liner. Although Sigg bottles are recyclable, and claim they do not contain BPA, they are made of aluminum, a toxic metal. If the bottle cracks, for example due to mishandling, the aluminum can get into the liquid. Ingestion of aluminum can lead to many serious health problems, including bone and tissue damage and neurological disorders.
Another downside to the Sigg aluminum bottle is the fact that the chemicals used in making the epoxy inner liner are not divulged by the company, but kept as a trade secret. It may be best to assume that this liner is as toxic as plastic, especially since epoxy normally contains BPA. Although Sigg has released a study saying their liner is BPA free, it is quite likely to be biased since the study was paid for by Sigg. It should also be pointed out that even though the Sigg study claims that their liner is BPA free, they didn’t test for BPA levels below 2 parts per million, thus, invalidating their results and claim that their product is BPA free. This type of deception makes consumers wary of Sigg water bottles.
One last fact that should be considered in the use of aluminum for water bottles is their possible negative impact on the environment. This is because the production of aluminum requires extensive energy, much more than various other materials used for water bottles.
So what material then is the safest and least harmful to the environment? Stainless steel! Stainless steel water bottles, such as Klean Kanteen, are much more likely to be a better alternative to plastic, glass or aluminum bottles. Stainless steel bottles are 100% recyclable, durable, do not alter the taste of ones contents and almost as lightweight as plastic. More importantly, stainless steel water bottles are also free from chemicals like BPA, and are safe to use with hot liquids.
Until further tests can be carried out to determine which, if any, plastic bottles can be used without long term risks, it is better to be cautious, and utilize stainless steel water bottles in order to avoid exposure to BPA or other chemicals that may pose a risk to one’s health.
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