ICS Magazine

MCS Concerns Can Redefine "Clean"

May 18, 2006


They have had their carpets cleaned in the past with products that were labeled non-toxic and still had a reaction. How do we determine what is non-toxic?

A: Before we define non-toxic, we need to understand what toxic means. The word toxic has been defined as "Having a chemical nature that is harmful to health or lethal if consumed or otherwise entering into the body in small quantities."

According to the Environmental Protection Agency, "The toxicity of a substance is its ability to cause harmful effects. These effects can strike a single cell, a group of cells, an organ system, or the entire body. A toxic effect may be visible damage, or a decrease in performance or function measurable only by a test. All chemicals can cause harm. When only a very large amount of the chemical can cause damage, the chemical is considered to be relatively non-toxic. When a small amount can be harmful, the chemical is considered toxic."

The toxicity of a substance depends on three factors: its chemical structure, the extent to which the substance is absorbed by the body, and the body's ability to detoxify the substance (change it into less toxic substances) and eliminate it from the body.

Are "Toxic" and "Hazardous" the Same?

No, toxic and hazardous are not the same. The toxicity of a substance is the potential of that substance to cause harm, and is just one of the factors used in determining whether a hazard exists or not. The hazard of a chemical is the practical likelihood that the chemical will cause harm. A chemical is determined to be hazardous based on the following factors:

  • Toxicity: how much of the substance is required to cause harm
  • Route of exposure: how the substance enters the body
  • Dose: how much of the substance enters the body
  • Duration: the length of time the subject is exposed to the substance
  • Reaction and interaction: other substances the subject is exposed to concurrently and their combined effect
  • Sensitivity: how the body reacts to the substance compared to its reaction in other subjects


Some common everyday products that are generally safe for use can be considered toxic given an unusual set of circumstances. For example, water is necessary to sustain life, yet if the dose is significant enough, it can be considered toxic.

Drinking too much water can deplete the body of essential electrolytes. Electrolytes are substances that become ions in a solution and acquire the capacity to conduct electricity. The balance of electrolytes in the body is essential for the normal function of cells and organs. In September of 2005, it was reported that a 32-year-old man in Liverpool, England died after drinking too much water. A pathologist said that the water had washed the essential salts from his body causing him to fall into a coma. Likewise, there have been a number of similar cases reported in the United States within the past few years.

Once more, a cleaning product is considered non-toxic "When only a very large amount of the chemical can cause damage..." Cleaning products that meet that definition can be labeled as such. That means that most of the population will not have a noticeable reaction to their use. However, there is a segment of the population that is highly sensitive to the same chemicals. According to National Institute of Allergy and Infectious Diseases, multiple chemical sensitivity, or MCS, "usually starts with either an acute or chronic toxic exposure, after which this initial sensitivity broadens to include many other chemicals and common irritants (pesticides, perfumes and other scented products, fuels, food additives, carpets, building materials, etc.)." Ohio State University published the following comments in an article on MCS, "...there seems to be no single stimuli or predictor of reactions" and "...the unique ability of each body to respond to different chemicals in different ways makes it difficult to understand the effects of any one chemical in a particular concentration on any person. Just as some people react adversely to certain medications while others do not, the way one person reacts to a chemical in the environment may be entirely different than another person."

Working with MCS clients requires more research and understanding. They may have sensitivities to a broad range of chemicals. Because they are highly sensitive, the criterion that is normally used to determine what is acceptable does not apply. OSHA's permissible exposure limits (PELs) and the American Conference of Governmental Hygienists' threshold limit values (TLVs) do not apply. Sometimes the only way to determine what cleaning products are usable in such a situation is trial and error. Additionally, what works with one MCS client may not work with the next. Some clients with MCS may know of products that they can tolerate versus others they cannot; others may fall into the category of not knowing what does and does not work for them at all. Clearly, providing cleaning services in these cases is highly complex and should be handled with the utmost care and concern.

According to John Banta, co-author of "Prescriptions for a Healthy House, A Practical Guide for Architects Builders and Homeowners," there are some things you can do to help assure your success when working with clients that suffer from MCS. People with MCS are often able to smell odors that cannot be detected by others. Therefore, cleaning equipment, hoses and supply tanks needs to be scrupulously clean. Any residual cleaners from previous jobs may contain perfumes or other components that may not be acceptable for your client. Just because you aren't bothered by the product, or can't smell it doesn't mean it will be acceptable for them.

Your client may not be able to tolerate the odors on your clothes from previous jobs, your laundry detergent or fabric softeners. They may also have difficulties with residual smoke odors, antiperspirants, colognes or other fragrances you use or pick-up from places you have been.

One suggestion would be to provide the client with a sample of the cleaning chemicals, labeling and MSDS sheets for any product you plan to use. This will allow them to self-test, or consult with their physician to determine if the product will be acceptable. If your client already has a cleaning product that works for them, it may be helpful to use the product they supply.

Another possible strategy would be to test the cleaning product on a sample of the material you will be cleaning. Sometimes the cleaning product will react with the material or other chemical treatments creating an unacceptable odor or condition for the client. Some products have been specifically developed for individuals with MCS, but even they don't work for everyone and require careful evaluation.

When asked to provide cleaning services for a client that has MCS, it is important to weigh the cost and time required to solve the problem versus the risk of failure to provide acceptable service. Solving such a problem can be very rewarding; however, it may not make good business sense to all professional cleaning firms. As the world population becomes progressively more sensitive to the environment, the increasing number of individuals with chemical sensitivities will increase the demand for professional cleaning firms to help solve the cleaning needs of their clients.