Among the hundreds of thousands of chemicals existing in our daily lives, these six classes are of particular concern with regard to the health of both the environment and ourselves (http://www.sixclasses.org/):
Highly Fluorinated Chemicals: Highly fluorinated chemicals are used in cookware, clothing, outdoor apparel, carpeting, and food packaging to provide oil- and water-resistant properties. They are persistent in the environment and have been detected in humans and biota all over the globe. In humans, some highly fluorinated chemicals have been associated with kidney and testicular cancer, thyroid disruption, elevated total cholesterol, and obesity.
Antimicrobials: Antimicrobials such as triclosan and triclocarban, are used in products from soap, deodorant, and toothpaste to socks, lunchboxes, and counter tops to prevent microbial growth. Antimicrobials can be ingested or absorbed through the skin and are detected in most Americans. They are a concern because they are associated with adverse endocrine, thyroid, and reproductive changes and their use can lead to resistant strains of bacteria. Soap and water can be a better alternative.
Flame Retardants: Flame retardants are used in furniture and baby product foam, building insulation, electronics, and other products to reduce fire hazard. They are detected in most Americans, with the highest levels in children, and they have been associated with endocrine disruption and reproductive, neurologic, and immune impairment as well as cancer. As currently used in furniture, building insulation and some other products, flame retardants do not increase fire safety.
Bisphenols & Phthalates: Bisphenols and phthalates act as endocrine disruptors, interfering with the hormone signaling mechanisms of the human body. They are found in plastics, pesticides, flame retardants, and other products and are measured in all humans. They can cause disruption to reproductive, metabolic, neurologic, and immune systems and the thyroid at very low concentrations and are most harmful during critical windows of development of the fetus.
Organic Solvents: Organic solvents are used in paint, coatings, degreasers, dry cleaning chemicals, and many other products in order to dissolve other chemical constituents. Many non-water based organic solvents release vapors that humans inhale and absorb. Some organic solvents are associated with neurotoxicity, reproductive toxicity, and carcinogenic effects during short-term high level exposure and over prolonged periods of low level exposure.
Certain Metals: Certain metals like lead, cadmium, beryllium, and mercury, have been harming human health for millennia. Metal toxicity can result in reduced mental and central nervous function, lower energy levels, and damage to blood, lungs, kidneys, liver, and other organs. Some metals like zinc that provide a health benefit in small doses can be toxic at high levels.