Six Classes for a Healthier Home

©. Six Classes

Sometimes groupthink is a good thing.

Remember Bisphenol A, or BPA? Everybody threw away their Nalgene bottles and all the companies reformulated their plastics to use Bisphenol S. But then, in "a strange déjà vu experience", researchers found that the substitute chemical was probably just as bad. The researchers noted that "the ability of manufacturers to rapidly modify chemicals to produce structurally similar replacements undermines the ability of consumers to protect themselves from hazardous chemicals and federal efforts to regulate them."

That's why the idea of the Six Classes approach makes so much sense. The Green Science Policy Institute, led by Arlene Blum (known to TreeHugger for her work on flame retardants), groups chemicals together, so that all the hormone-disrupting chemicals like bisphenol and phthalates are thought of as one class of chemicals to avoid.

Bisphenols and Phthalates

It is a logical approach; instead of just looking at, say, plastic bottles, it connects everything from epoxy can liners to cash register receipts to food packaging to rubber duckies. More at Six Classes

Fluorinated chemicals

It is an easy-to-understand approach, when you start to think about where all these highly fluorinated chemicals are used, which are linked to "kidney and testicular cancer, elevated cholesterol, decreased fertility, and thyroid problems and decreased immune response to vaccines in children." I do wish they would include PFC coated dental floss in their lists, as people are putting this stuff in their mouths. More at Six Classes


Triclosan was the big one that we have covered for years on TreeHugger, but here are others still found in soaps and body washes. Triclosan is being replaced with chemicals like nano silver and quats, which have their own problems. We don't need any of them. More at Six Classes

Flame Retardants

This is where we first met Arlene Blum; she was quoted often in BuildingGreen. They are still used by the ton in furniture and insulation, although you can now legally buy furniture that doesn't have them. They are not chemically bound to the plastics into which they are mixed, so they can leach out, and they have an affinity for dust bunnies. "Some flame retardants are associated with lowered IQ and hyperactivity in children as well as cancer, hormone disruption, and decreased fertility in adults."

It's one of the main reasons we dislike foam insulation. More in Six Classes

Some solvents

When I practiced as an architect I loved the smell of my Pantone markers and am convinced that I sometimes got a little high while colouring a drawing. Many of these chemicals can cause serious problems, and as building codes get tougher and our houses get tighter, they become more of a problem than ever. None of these should be stored in our homes, and household cleaners should be chosen carefully. Again, here is where you have to think of classes and groups:

When toxic solvents are phased out, they are often replaced with similar solvents. For example, toluene has largely been phased out in nail polish, but is replaced by its chemical cousin xylene which appears to have similar effects. In dry cleaning, perchloroethylene is often replaced in by another organohalogen solvent, 1-bromopropane, which is also a likely carcinogen.

More at Six Classes.

Some Metals

Most of these are now illegal in North America, but there is still a lot of lead in tasty sweet old paint, and there is a bit of arsenic in rice and still a bit of mercury in fish. More at Six Classes

A good kind of Groupthink

This all makes so much sense. Instead of getting into the individual chemicals, it looks at the larger groupings. It helps explain why we should try to live without plastics, use natural materials instead of foams with fire retardants, healthy cleaners instead of toxic solvents. It is simple and straightforward. I hope it catches on.