Plastic Containers
What The Public Should Know About Plastics and Bisphenol A
Bisphenol A is a troubling chemical that disrupts hormones and has been shown to be harmful to both humans and the environment.
Plastics, resins and polymers have invaded every aspect of modern life since the introduction of the first man- made plastic in London at the Great International Exhibition of 1862. The evolution of plastic over the next century was meteoric.
Today it is nearly impossible to avoid plastics but a recent interest in their compostiton has consumers worried about the chemical bisphenol a (BPA). Testing of older baby bottles, plastic water bottles and epoxy can (food) liners have revealed startling levels of BPH. How wide spread is BPA toxicity and what are some of the ramifications?
A BPA PrimerBisphenol A is a chemical in plastics that has been known to be harmful to human beings since the 1930's. It is disrupts normal hormone production and studies have just begun to explore how thoroughly the substance penetrates the blood-brain and placental barriers.
The most common uses are in clear plastic drink bottles. The polycarbonate form of BPA makes the bottles more shatter or leak resistent. It is also widely used in everything from dental appliances to eyeglasses. Even CD's and DVD's contain BPA Polycarbonate.
Expsoure to BPA has now been linked to cancer, decreased immune function, obesity, diabetes, hyperactivity in children, and other extremely serious health issues.
BPA is a volatile organic compound and as such is known to off-gass and affect indoor air quality. When heated, as in microwaving plastic food containers, BPA has been shown to leech into foods. The Food and Drug Administration's current upper limit of BPA uptake is 50 micrograms per kilogram of body weight per day but this number is based on research that was done in the 1980's.
Newer studies call into question these old findings and have raised alarming concerns. Scientists now believe that BPA poses serious health risks at .0024 micrograms (or less) per kilogram of body weight per day. Information obtained from FDA documents and epa.gov suggest that these agencies are close to making some announcement regarding reevaluated safe levels of exposure to BPA.
Grading of Plastics
There are currently seven grades consumer plastics. The grading can be found on the bottom of the container within a small triangular symbol. The symbol is generally slightly raised, very tiny and consists of a triangle with a number value from one to seven.
- grade 1 is used primarily for drinking bottles, medicine bottles and microwavable containers
- grade 2 is slighlty thicker ployethylene used for milk jugs, shampoo/soap bottles and laundry detergent bottles
- grade 3 is Polyvinyl Chloride is used for plastic food film and more rigid plastic containers
- grade 4 is low density polyethlene and as such is used in newspapers and grocery bags
- grade 5 is Polypropylene and used for yogurt containers and some deli/catering trays
- grade 6 is Polystyrene used for take out containers and plastic cups
- grade 7 is a mixture of resins and used in miscellaneous plastic containers and products
Concerns About Plastic Food Containers
The extent of exposure to BPA's is extremely widespread. Just eating one serving of a canned vegetables (from a can with an epoxy liner) provides nearly double the amount of BPA the FDA currently considers average dietary uptake.
No matter how conscientious consumers may be, avoiding BPA may be impossible but there are steps people can take to limit exposure. Buy as many items as possible in their natural fresh state instead of cans, plastic bags or film wrapped trays. New paper tetra- packs are available for some juices and milks.
Never heat foods in plastic containers. Do not reuse plastic containers over and over. Even if not heated, they still break down after continued use. Do not steam vegetables in plastic bags either. BPA-free plastic drink bottles, sandwich wraps and various other products are widely available online and beginning to appear in local supermarkets due to consumer demands for safer products.
Keep in mind that natural is always best. It may not always be the most convenient or the quickest way to cook and store foods but it is the safest.
Resources
bisphenolfree.org
epa.gov
"Plastics May Not Be So Fantastic For Kids" Los Angeles Times, Sept 2007
Hormone Desception: How Everyday Foods And Products Are Disrupting Your Hormones by Lindsay D. Berkson, McGraw- Hill 2001
Posted via email from Harris' posterous