Monday, March 29, 2010

Plastic Containers

The container that holds and/or heats liquid or solid food as well as water may be more important than its contents. In the last 3 decades, there has been a 500% increase of plastics used in our immediate environment to include cups and bottles. The three worse offenders are Phthalates, Biphenol A and styrofoam. These bind to various hormone receptors such as estrogen and thyroid and are known as Hormone Disrupters. Also the Styrofoam hydrocarbons in cups or other bottles can cause cancer.

Phthalates, or phthalate esters, are esters of phthalic acid and are mainly used as plasticizers (substances added to plastics to increase their flexibility, transparency, durability, and longevity). They are primarily used to soften polyvinyl chloride. Phthalates are being phased out of many products in the United States and European Union over health concerns. Phthalates are used in a large variety of products, from enteric coatings of pharmaceutical pills and nutritional supplements to viscosity control agents, gelling agents, film formers, stabilizers, dispersants, lubricants, binders, emulsifying agents, and suspending agents. End applications include adhesives and glues, agricultural adjuvants, building materials, personal care products, medical devices, detergents and surfactants, packaging, children’s toys, modelling clay, waxes, paints, printing inks and coatings, pharmaceuticals, food products, and textiles. Phthalates are also frequently used in soft plastic fishing lures, caulk, paint pigments, and sex toys made of so-called “jelly rubber.” Phthalates are used in a variety of household applications such as shower curtains, vinyl upholstery, adhesives, floor tiles, food containers and wrappers, and cleaning materials. Personal care items containing phthalates include perfume, eye shadow, moisturizer, nail polish, liquid soap, and hair spray. They are also found in modern electronics and medical applications such as catheters and blood transfusion devices. The most widely used phthalates are the di-2-ethylhexyl phthalate (DEHP), the diisodecyl phthalate (DIDP) and the diisononyl phthalate (DINP). DEHP is the dominant plasticizer used in PVC due to its low cost. Butyl benzyl phthalate (BBP) is used in the manufacture of foamed PVC, which is mostly used as a flooring material. Phthalates with small R and R’ groups (attached organic molecules) are used as solvents in perfumes and pesticides.

Phthalates are easily released into the environment because there is no covalent bond between the phthalates and plastics in which they are mixed. As plastics age and break down the release of phthalates accelerates. Phthalates in the environment are subject to biodegradation, photodegradation, and anaerobic degradation and, therefore, they do not generally persist in the outdoor environment. Indoor air concentrations are generally higher than outdoor air concentrations due to the nature of the sources. Because of their volatility, DEP and DMP are present in higher concentrations in air in comparison with the heavier and less volatile DEHP. Higher air temperatures result in higher concentrations of phthalates in the air. PVC flooring leads to higher concentrations of BBP and DEHP, which are more prevalent in dust.

People are commonly exposed to phthalates, and most Americans tested by the Centers for Disease Control and Prevention have metabolites of multiple phthalates in their urine. Because phthalate plasticizers are not chemically bound to PVC they can easily leach and evaporate into food or the atmosphere. Phthalate exposure can be through direct use or indirectly through leaching and general environmental contamination. In the Midwest, many fish in streams are banned from human cosumption because of the adulteration of the water from public and private landfills. Diet is believed to be the main source of DEHP and other phthalates in the general population. Fatty foods such as milk, butter, and meats are a major source of toxicity, since they more rapidly absorb these lypophillic chemicals. Low molecular weight phthalates such as DEP, DBP, BBzP may be dermally absorbed. Inhalational exposure is also significant with the more volatile phthalates. Looking at the Recycling triangle on the bottom of the container will give more information than you need.

The actual risks of BPA are still a matter of public debate, but over the past decade, a growing body of scientific studies has linked the chemical to breast and prostrate cancer, infertility, obesity, and neurological and behavioral changes, including autism and hyperactivity. Bisphenol A is also an endocrine disruptor, it can mimic the body’s own hormones, which may lead to negative health effects if the dosage is high. There are theories that it may contribute to body fat development. A September 2008 study in the Journal of the American Medical Association found that higher levels of urinary BPA is associated with cardiovascular disease, diabetes and liver-enzyme abnormalities.

Styrene is made from benzene which has been clearly shown to be carcinogenic. The migration of styrene from a polystyrene cup into the beverage it contains has been observed to be as high as 0.025% for a single use. That may seem like a rather low number, until you work it this way: If you drink beverages from polystyrene cups four times a day for three years, you may have consumed about one foam cup’s worth of styrene along with your beverages. Styrene migration has been shown to be partially dependent on the heat and fat content of the food in the polystyrene cups/containers—the higher the fat content and the temperature, the higher the migration into the food. Entrees, soups, or beverages that are higher in fat (like a bowl of three-cheese chili or tall cupful of Triple-Cream Frappa-Mocha Java Delight) will suck much more of the styrene out of the polystyrene container than water. Some compounds found in beverages, like alcohol or the acids in “tea with lemon,” may also raise the styrene migration rate.
PLASTIC CODE IDENTIFCATION: Containers with a 3, 6, or 7 on the bottom are the most dangerous of all. They contain a dangerous and volatile chemical called BPA, and should be avoided at all costs. Containers with a 4 or 5 on the bottom are generally considered safe. But you should probably use them sparingly. And you should never use them in a microwave.
Containers with a 1 or 2 on the bottom are the safest. These include clear water containers, as well as most cloudy containers you normally find containing water or milk. These containers, called PET and HDPE, are safe for storing food and drink. But again, you should never use them to microwave.

The #7 recycling label is a catchall indicator for plastics made with a resin other than those in the #1 to #6 designations, or made of more than one resin. The #7 category not only includes polycarbonate, but also includes compostable plastics made of organic material and other types of plastic that do not necessarily contain BPA (Bisphenol-A). For example, the new Everyday™ line manufactured with Eastman’s Tritan™ copolyester is a #7, but does not include BPA.
Of all the seven grades of commercial plastics available to manufactures on today’s market, unlucky #7 has the worst track record for leaching the chemical known as BPA into liquids or foods likely to be consumed by humans or animals. The reason is because unlike the other six composites, containers bearing the number seven are made of a composite of leftover scraps that have been ‘repurposed’ and most likely purchased at a discount. The new Nalgene water bottle is made of a “copolyester” plastic manufactured by the Eastman company with the trade name Tritan. So are new bottles by Korand Campelbak. All trumpet the fact that their bottles are BPA-free, with the implication that BPA-free is the equivalent of safe. But there is no way of knowing because the ingredients that make up Tritan have been kept secret. They could include another dangerous chemical. Since the ingredients have not been identified, no one can say. All that is known about the Tritan bottles is that, like polycarbonate, they fall into the #7 category of “other” plastics in the identification system.

When purchasing cling-wrapped food from the supermarket or deli, slice off a thin layer where the food came into contact with the plastic and store the rest in a glass or ceramic container or wrap it in non-PVC cling wrap. Avoid storing fatty foods, such as meat and cheese, in plastic containers or plastic wrap. Hand-wash reusable containers gently with a nonabrasive soap; dishwashers and harsh detergents can scratch plastic, making hospitable homes for bacteria.
“Microwave-safe” or “microwavable” label on a plastic container only means that it shouldn’t melt, crack or fall apart when used in the microwave. The label is no guarantee that containers don’t leach chemicals into foods when heated. Use glass or ceramic containers instead. Some scientists feel that the microwaves change the healthy vibrational frequency of the food to a unnatural and less compatible with our digestive/metabolic system.

6 comments:

  1. I am responding on behalf of the Styrene Information and Research Center, Arlington, Va. While we all are concerned about food safety, we believe that blog postings such as this one do more to alarm readers than to inform them. Concerning styrene (from which polystyrene, aka Styrofoam is made) and hormone disruption, we hope that readers will consider with the U.S. National Toxicology Program's Center for Evaluation of Risks to Human Reproduction has to say at http://cerhr.niehs.nih.gov/chemicals/styrene/StyreneMono-www-s.pdf. It found "negligible concern for adverse developmental and reproductive effects resulting from styrene exposure in humans." Concerning styrene and cancer, no regulatory agency anywhere in the world considers it to be a known human carcinogen. A recent peer-reviewed report by a panel of eminent scientists, published in the Journal of Occupational and Environmental Medicine, found that the "available evidence does not support a causal relationship between styrene and exposure to any type of human cancer." We encourage readers to visit www.styrene.org for accurate information concerning styrene, and www.americanchemistry.com/pfpg for accurate information on the safety of polystyrene foodservice.

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  2. "Negligible concern?" Looking around at the questions brought about and what I am seeing in our society, it is simple to find alternatives to plastics. Plastics are the double edged sword due to our planet's plastic pollution problems. Food safety issues in question will have me avoiding the platic wrap as mush as possible!
    It is apparrant that manufacturers will come forward to save thir product's reputations and minimize health risk questions. I am playing it safe. We only know what we are told and the slant depends on where we choose to get our information from.
    Gradually finding the alternatives to plastics and phasing out all plastics makes the most sense to me.

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  3. "Why would the National Sugar Board lie to us?" ~ Marge Simpson

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  4. So much money is being spent on Nuclear Weapons production, something we'd better not use. Why spend billions on a toxic product that nobody wants? Well, they'd tell you it will make you safer...use it or not, it costs a lot to make and still needs to be disposed of somewhere, somehow. And why make so many? And why not stop making them? Seems like plastic is here to stay, come what may: a science experiment! Stop buying it.

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  5. @Joe Walker - You are correct. Styrene is not carcinogenic, nor does it have teratogenic properties (to my knowledge). It is, however classified as a systemic toxin. Styrofoam on the other hand is made from polystyrene, and is made with not only styrene, but also benzene, which has been proven in study after study as a carcinogen as well as a systemic toxin. Stop clouding the facts to sell your product. People are dying.

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  6. hi the post is awesome . thanks for sharing such an informative post.

    Bulk Containers

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