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Having been invited to give a presentation at an upcoming scientific congress on the topic of cleaning agents and allergy on-the-job, I found that I needed to brush up on the subject. As it turns out, this is a very broad topic but not a bit esoteric. In fact, it's all too much an everyday affair.
The subject of cleaning products and health has many different facets. First off, I had to think through what "on the job" means when it comes to using cleaning agents. If you restrict the meaning narrowly to be salaried employment only, then you cut out the vast majority of people who do cleaning in the home and do it for no remuneration at all. Even domestic cleaners who are paid most often work in a very different way from industrial-scale cleaners and custodians in hotels, hospitals, schools, and offices. An even bigger question-mark emerges when trying to classify the myriad of exposures that can be involved in cleaning, examining their effects to see how they might or might not intersect with "allergy." Cleaning products run the gamut from disinfectants and degreasers to polishing agents and scouring abrasives to coating materials, waxes, and sealants, with delivery in the form of pressurized aerosols, atomizers, powders, creams, and liquids. To paraphrase Tolstoy, all benign cleaning agents are more or less the same, but each cleaning product usage that can go wrong seems to be unique unto itself.
One of the most common modes of cleaning gone wrong is when hypochlorite bleach is mixed together with a second cleaning product. This misadventure sometimes, but not always, is unintended. Whether on purpose or not, when bleach is mixed with an acidic co-product the result is a little cloud of an old-fashioned war gas called chlorine. The acid can be as simple as old-fashioned vinegar (a favorite element of some "natural cleaning" protocols) or any one of a number of stronger acids used to clean tile, toilets, or other surfaces. Just look for muriatic or phosphoric acid the next time you check the labels of such products in your supermarket or hardware store aisle. Even Dr. Laundry on the Clorox website admits mixing bleach with acid (or ammonia) may not be a good idea (http://www.clorox.com/blogs/dr-laundry/2008/12/18/cleaning-tile/).
Chlorine-laden gas or mist causes coughing and choking. Usually, these symptoms pass after a time, even among persons so heavily exposed that they have to seek medical care. But in a subset of cleaning product gas warfare victims, a form of asthma develops and persists. Recent studies have shown that those who clean with bleach frequently, for a pay or not, are at increased risk for asthma, perhaps double that of persons without such exposure. Importantly though, this asthma doesn't seem to be allergic in the usual sense of the term. People are not sensitized to chlorine or hypochlorite bleach the way they can be and frequently are to dust mites, for example. Needless to say, the professional or freelance cleaner who is allergic to dust mite has yet another challenge to contend with on job.
Although chlorine does not induce an allergic response, other cleaning agents can do so. This can be manifest not only in asthma symptoms, but also as a persistently runny nose (rhinitis) or even in a skin rash (dermatitis). Further, the allergy-causing component in a cleaning product need not be its main ingredient, but rather a chemical added to provide an inviting aroma or to act as a preservative. Many times these additives are not even listed on product labels. There is even some indication that certain chemicals, including some contained in household cleaning products, may have the potential to stimulate responses to a second unrelated material, for example, any of a number allergens that are in our everyday environment.
Anyone who cleans in their own home has a choice as to what cleaning products to use, but salaried cleaners, domestic or industrial, may have far less say over what materials they employ. Good old soap and water is often the best all-purpose cleaner. Other general good practices should include: sticking with a limited number of products; avoid mixing different agents, even sequentially on the same surface; minimize bleach and pressurized spray applications; and, if a cleaning product makes you sneeze, wheeze, or itch, don't use it. Anyway, that's what I learned.
