Warning: chemicals are more toxic than they appear.

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[by Christine Lepisto]

It seems like you can't open a newspaper or magazine without reading warnings about hazards "you must avoid." Though many are carcinogenic and can pose serious health risks, which ones are the worst? Which ones do you really have to watch out for?

Benefits vs. risks

We each weigh the benefits of certain products (and the chemicals that are in them) against the risks associated with their use. For example, the tar and other nasties in cigarettes would top any such list -- we know that they cause cancer and are really bad for you and anyone who's around you a lot. But, people around the world still smoke them, despite piles of studies and mountains of information that say they're not good for us. The same applies, in degrees, to the benefits of make-up, shampoo, toilet cleaner, auto lubricants, and a host of other products that the average person uses and relies upon each day.

What We Really Want to Know

So let's skip alcohol and saturated fats and go straight to what we really want to know about what to avoid: which chemicals lurk in everyday consumer products which can be avoided without really harming our quality of life or threatening our freedom of choice?

1. Triclosan

Once restricted to uses with high benefit and limited proliferation, such as in hospitals and food-processing, successful marketing of anti-bacterial agents in consumer products led to a boom in the amounts of these germicides in our environment. The CDC estimates that in the early 1990s, only a few dozen products containing antibacterial agents were being marketed for the home. Now hundreds flood the market. Triclosan is in human breast milk and in fish downstream of water treatment plants. It has been shown to act as an endocrine disruptor in frogs. Ironically, this futile quest for sterility may be breeding super-bugs resistant to antibiotics or harming the good bacteria which help us stay healthy. If you quit only one chemical habit after reading this, give up anti-bacterial soaps and cleaners. If you don't buy these products today, talk to your friends and neighbors. This one is a no-brainer.

2. Bisphenol A, or BPA

This chemical, used to make certain plastics soft and pliable, continues to be named in studies implicating it in health risks. Recently, the first large-scale human study correlates bisphenol-A with common diseases such as heart disease, type 2 diabetes and liver enzyme abnormalities. (JAMA, Lang and colleagues).

But the controversy continues: while Canada banned BPA in 2008, the US FDA continues to defend BPA as safe—even for babies. To minimize your exposure: buy preserved foods in glass instead of cans, especially those with an acidic nature such as tomatoes or citrus fruits; avoid drinks in single-use plastic bottles; and never microwave food or put hot foods in plastic containers.

3. Perfluoroalkyl acids and salts

Perflurooctane sulfonates, PFOS, lead this pack. The media has dubbed these chemicals "C8" with much the same na

Perfluoronates were heralded as chemical wonders for their non-stick and water-repellant properties. An OECD study shows 2005 production levels in the hundreds of tons around the world. While scientific knowledge about the toxicity and chronic effects of this chemical are incomplete, one thing is clear: these persistent and bio-accumulating chemicals are building up in mammals across the planet. Enough evidence exists to use the precautionary principle to stop all applications which do not provide substantial benefits offsetting the risks. Non-stick cookware and stain-repellant trousers simply do not merit gambling with these bad actors. [Note: do not throw away non-stick cookware you own. The risk is in the manufacture, not in the end product.

4. Phthalates & 5. Nonylphenol and its ethoxylates

These are the poster children for endocrine disrupting chemicals. That big medical term means that the chemicals mimic natural hormones, like estrogen or androgen, which causes confusion in the systems regulating sexual function. Disappearing male populations, small penises and hermaphrodite fish are just a couple of observed phenomena that may be explained by a build-up of endocrine disrupting chemicals in the environment.

Phthalates are used to make plastic flexible, as solvents, and in cosmetics and perfumes. Again, this is a family of chemicals. The misbehaving siblings include dibutylphthalate (DBP), butylbenzylphthalate (BBP) and diethylhexylphthalate (DEHP), while Diethylphthalate (DEP) appears to be safer.

Nonylphenol compounds are effective, cheap surfactants (surfactants are the chemicals which help dissolve oily grime into water in cleaning products). There are many safer substitutes, so simply don't accept any "nonylphenol" on the ingredient list of products in your house.

6. Polybrominated Flame Retardants

Exemplified by Polybrominated diphenyl ether (PBDE) and Polybrominated biphenyl (PBB), polybrominated flame retardants are used in mattresses, upholstery, plastics and other materials to prevent them from catching fire and burning. In the battle of risks versus benefits, some jurisdictions, such as California, require PBDE and others, such as Europe and China, have banned PBDE. Although flame retardants prevent risks from synthetic materials burning, they are persistant and bio-accumulating. Adverse health effects attributed to PBDE and PBB include problems in brain development and genital malformations. Avoid polybrominates by buying clothing, bedding and furniture made from natural materials.

Find out what else is on the list in part two of "Avoid These 'Dirty Dozen' Toxic Chemicals."