A guide to chemicals in the kitchen, utility room, bathroom and living room.
Each day the average American uses (directly and indirectly) hundreds of laborsaving formulations, and even the conscientious consumer is likely to be coerced into pushing the buttons on a few spray cans. In the last 50 years, chemicals (that is, those of the synthetic variety) have become an integral part of the U.S. way of life—not to mention of our economy.
It would be easy to rail against the trend. After all, a hundred years ago people got along pretty well without an arsenal of aerosols. What's more, the harmful effects of chemical production and the disposal of its by-products may be the most serious environmental problems facing the country today. Indeed, there are frighteningly dangerous compounds that continue to be manufactured and used, despite widespread scientific knowledge of (and complaints about) their harmful effects. Only public outcry will bring grease to the wheels of regulation in a government bogged down in bureaucracy and badgered by commercial interests.
However, it's consumer self-defense (not action) that's the subject of this article. As you'll learn, federal regulation is no assurance of safety from a whole array of compounds many of us use in our own homes. We'll be discussing substances that are much more insidious than newsworthy contaminants such as dioxins or polychlorinated biphenyls (PCB's), even though they are much less dangerous on a per-unit basis. Most consumers are practically unaware of them, because the compounds may go unmentioned on labels or because their names are indecipherable. Some of the chemicals are additives that are known to be hazardous. Others are dyes or flavorings that have never been adequately tested. But the most sinister aspect of the proliferation of household chemicals is that most of us expose ourselves to these laborsaving elixirs for hours on end in our own homes every day. In effect, we live in chemical warehouses.
Over the last few years, a major chemical company has used advertisements in its attempt to make the point that since all matter is made up of chemicals, that term certainly isn't a dirty word. Whatever you may think of the firm's motivations, the ads do make a worthwhile point: Simply because a compound sounds complex, that doesn't mean it's dangerous. Unless you have a strong background in chemistry, you probably won't be able to tell a harmful substance from a beneficial one purely on the basis of its name. For example, vitamin B6 (an essential nutrient) goes by the technical names of pyridoxine or pyridoxine hydrochloride, either of which is a fair mouthful to pronounce.
Likewise, simply being of natural (rather than synthetic) origin is no guarantee of a substance's safety. The ranks of suspected and known toxic and cancer-causing compounds are filled with plants and minerals. Generalizations really don't go very far when we're discussing hazardous substances. To make sensible decisions about the chemicals you live with, you'll need to be well armed with information.
There are a number of different and fairly obvious ways in which chemicals can harm us, but judging the degree of risk is a very difficult matter. Toxic compounds cause one or more of a variety of bodily malfunctions. Perhaps they depress the central nervous system, making us drowsy or even causing death. Or maybe they attack the liver, where they accumulate when they're cleaned from our blood. The question is, how much of a particular substance does it take to cause such harm? If an inordinately high dosage must be taken to harm a human, the substance may be considered toxic but not hazardous.
Only if that toxicity level is within the range of normal human intake (and a large margin of safety is used in the calculation) is it considered hazardous. The issue of toxicity is further complicated by the fact that bodily harm can be produced in a couple of different ways. A toxicant is said to be acutely toxic if it triggers a reaction soon after a single ingestion; a chronic poisoning may not produce symptoms until the compound has accumulated to a threshold level in the body—days, months, or years later.
Scientists have developed a system for denoting the comparative toxicity of substances. Known as "lethal dose, 50%" (LD50), it indicates the amount of a compound that must be administered to cause half of the test sample to die. For obvious reasons, LD50 tests aren't run on humans; mice or rats are the most common "guinea pigs". The results can't be directly compared to human exposure, though, because animals don't necessarily react to toxicants in the same ways that people do.
The tested chemicals are also administered in different fashions—orally, by under-skin injection, directly into the stomach, etc.—which can influence the outcome of an experiment. A substance may not be readily absorbed through the skin, while inhalation may allow it to pass through lung tissue quite easily.
Furthermore, LD50 isn't necessarily a good measure of chronic toxicity. Though a large quantity of a compound may be required to produce immediate death, much smaller amounts may add up—over continuous exposure—to life-threatening levels.(Lead poisoning is a good example of this phenomenon.) Extended, expensive studies are required to determine chronic effects.
There are further complications in the matter of determining the safety of a substance. For example, though allergy studies are seldom done prior to the introduction of a chemical to the market, many substances can have life-threatening effects on people with asthma. Also, in a process called synergism some comparatively innocuous chemicals may combine with others to increase the risk of each or to form a different (and more hazardous) substance. To date, the general population—that's us—is essentially the test sample for problems of this sort.
Furthermore, though the measure of a chemical's toxic or allergenic effect on humans is inexact, those techniques are models of precision compared with the process of calculating a compound's cancer-causing potential. First of all, there is the unanswered question of how cell mutation relates to cancer. If a compound produces genetic mutation in laboratory experiments, it's said to be mutagenic. If it produces cancer in humans or animals, it's said to be carcinogenic. Most, but not all, mutagens turn out to be carcinogens; so far, all carcinogens have proven to be mutagenic. Yet another type of mutating (but not necessarily cancer-causing) compound is a teratogen, which causes malformation in the fetus.
Substances are tested for carcinogenicity by administering large dosages (usually hundreds or even thousands of times the amount found in normal human exposure) to laboratory animals over a period of a few weeks to a few years. It is assumed that the production of cancerous cells (if there is any) can be speeded up by increasing the dosage to very high levels. Industry isn't patient enough to wait 20 or 30 years to look for evidence of increased cancer from the use of a substance that they propose to put on the market. In addition, the life spans of most test animals are comparatively short. If no cancer is evident, then the substance is considered to be safe. But if some tumors show up, then the risk to humans is calculated by the dosage level and the incidence. The resulting figure estimates the number of cancer deaths per unit (usually thousands or millions) of population.
The Reagan Administration has attempted to change Food and Drug Administration and Environmental Protection Agency policy from a no-risk cancer stand to a cost-benefit one. Though the officials have been unsuccessful in developing a way of assigning dollar values to cancer deaths, regulations have been altered to allow a higher incidence of cancer from the use of some substances. The methods, regulations, and economics of determining the hazards of chemicals are nothing less than a morass; from our point of view they can probably be summed up thus: Will possibly hazardous compounds be considered innocent until proven guilty?
We've divided the subject matter of a guide to hazardous household chemicals into four sections, according to the locations in which you're likely to encounter different categories of harmful chemicals. You'll note as you read through the information that many of the substances are used in all sorts of consumer products. Formaldehyde, for example, is ubiquitous in the household. Therefore, for the sake of space, we'll often direct you to a previous discussion of a commonly occurring substance's effects.
Each room of our model household includes an introduction to the regulations that help protect us from the dangerous substances that might be found there. This is necessary because different wings of our government deal with food, cleansers, building materials, etc. In some cases, we'll find that there is, in effect, no regulation at all! For those of you who will use the compounds that make up the body of each section, the labeling requirements that the agencies impose on different types of products will be extremely important. Without labels, you can do little more than suspect what may be included in a product.
Of course, this manual can only highlight those toxicants and carcinogens that have been judged by experts to pose the most direct danger to you. There are a number of important areas that we've been forced to pass over, because not even these pages are enough to address all the hazards around the house. In general, we've tried to hit areas where consumers are least protected and most likely to be unaware of the existing hazards. Hence, we've not covered the synergistic reactions that can occur between common ingredients and prescription drugs. (Your physician should inform you of the interactions that are possible whenever he or she writes a prescription. In addition, an excellent reference to drug interactions can be found in Joe Graedon's People's Pharmacy-Two [Avon Books, 1980). Nor have we covered potentially dangerous household appliances, from microwave ovens to lawn mowers. All of the items listed in the following pages are substances that can cause you harm.
The lists have been compiled by sifting through mounds of books and reports to pinpoint those chemicals (of the thousands introduced annually) that are both dangerous and commonly used. Throughout the mini-manual we've tried to list sources of more information. You should know, though, that since the 1980 election it seems to have become increasingly difficult to gain access to such information. References in popular and technical literature have dropped to a mere trickle. To that extent, preparing this section has been very frustrating: All too often there are no concrete answers to the question of whether a substance is hazardous or not. Wherever there is doubt, we hope we've erred on the side of safety!
If you were to sit down and read this manual from beginning to end, you might come away with the impression that the situation is hopeless . . . that there's just no way to avoid hazardous substances. And it's true that most of us are going to be unable (or unwilling) to stay away from everything dangerous all the time. The point of this manual, though, is not to suggest that you should never again touch any of the things mentioned herein. Rather, we hope that you'll use the information to help recognize substances that may pose a hazard (even if it's small) and to limit your exposure to whatever degree is possible and practical. With knowledge, you can do your best for yourself and yours.
To learn about specific household chemicals and hazardous substances, see Hazardous Substances in the Kitchen: Food Safety and Food Additives, Hazardous Substances in the Utility Room: Household Cleaning Products, Hazardous Substances in the Bathroom, and Hazardous Substances in the Living Room.