Sustainability in Clothes Washing

Sustainability in Clothes Washing

by Richard M. Goodman

A previous blog post addressed the relative hazards or toxicity of cleaning chemicals, emphasizing that minimal human toxicity and environmental impacts promote sustainability.  In addition to detergent selection, another aspect of the simple household chore of clothes washing is the energy utilized.  Depending on the size of your family and how frequently you wash clothes, the energy consumption can be significant.  The major consumer of energy in clothes washing is normally the heating of the water used.  In fact, if you normally do a wash load at say 130 degrees F, your energy consumption is actually 60% greater than if you used 85 degrees.  Further, with the availability of many cold water laundry detergents which use  environmentally green formulas, there is no need to ever use water above 85 degrees.

Another aspect of the home laundry energy usage is the nature of the hot water system in your home.  In one extreme is the typical old-fashion poorly insulated electric hot water tank.  In a climate like Bethesda, the energy consumption of such a tank can be up to 25% of total household energy usage.  Highly efficient modern, especially natural gas, hot water heaters can significantly cut down on energy usage versus the typical tank, perhaps 50% or more.  Of course, if you use 100% solar to heat your hot water your energy usage is virtually zero.

So, here again by paying attention to a routine household activity you can promote sustainability by dramatically reducing energy usage to perform the simple act of cleaning your clothes.  Saving energy for the same material outcome is the very definition of sustainability. And by optimizing the efficiency of your hot water tank and always washing clothes at 85 degrees or less you could potentially save about 5-10% of your total household energy costs even without the use of solar derived hot water.

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.

 

Facts on Sustainability of Household Cleaners

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: 7^th 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.