Facts on Sustainability of Household Cleaners
by Richard M. Goodman
The current issue of Consumer Reports includes an article titled, “Is your home making you sick?” Within this article is a separate box on “household cleaners. ” The issues highlighted include the topics of contaminants, fragrances, especially the question as to whether some ingredients react together or with, for example, ozone to form formaldehyde or other carcinogenic materials. Let’s investigate further the comments found in this article to uncover the science it contains.
Toxicity relates directly to the testing of chemicals. Every industrial chemical must provide a material safety data sheet for its transport and handling. You can determine the overall safety of a component by a simple computer search for the chemical name (read it off the contents of the bottle) and the letters MSDS. Some examples: 7th generation cleaners contain myristyl glucoside, sodium gluconate among other ingredients. When you click on the relevant MSDS sheets, you will find that for both of these ingredients there are no exposure limits and toxicity is below reportable limits, i.e. completely safe.
When the component is a fragrance, then it may no longer be a single chemical substance. In fact, many are complex mixtures of natural substances. On the other hand, fragrances are almost always less than 1% of the weight of the ingredients (the EPA limit for unlisted chemicals); further, some of the pure components may be less than 1% of the fragrance total. Thus, though one of these components of a fragrance is for example a terpene with known toxic effects, it is in such small concentrations (parts per million) as to be below any threshold for toxicity.
Ironically, some recommendations for a substitute “green’’ cleaning component list white vinegar. However, this contains ~5% acetic acid. According to its MSDS, acetic acid is actually considered a slightly stronger hazard because it is highly irritating to the eyes and if directly ingested is actually a serious intestinal irritant. However, since we normally handle and consume vinegar we discount the objective fact of its relative toxicity as a chemical. Another example is the ammonia (ammonium hydroxide) used in most window cleaners. Ammonia is a relatively dangerous chemical. In commerce to industrial laboratories, ammonium hydroxide is shipped in special containers and lab technicians are instructed do open these with great care while wearing gloves, respirators and face shields. Often homeowners clean glass surfaces with no protection whatsoever.
This leads to the key message of this article. We should not panic or overreact merely because one reads that a “chemical” is hazardous, or toxic or may react to form carcinogens. The more familiar we are, the more we downgrade the risks while often discounting the effects of dose, concentration and how a product is used.
Richard M. Goodman, PhD, is a chemical scientist and consultant focusing on how surface science concepts can solve real world problems. The periodic column considers aspects of sustainability from a scientific perspective. See Goodman’s profile with Association of Consulting Chemists and Chemical Engineers (ACC&CE) at www.chemconsult.org.