What do you think of when you read the title of this chapter: a sky darkened with billowing clouds from hundreds of smoke stacks, trucks overturn on highways and spill drums containing toxic material, or chemical slime that seeps from holding dams into a town’s water supply? This would be my first reaction. But have you thought of the ‘low-irritant,’ ‘rainforest-fragrant,’ ‘fast knock-down,’ fly spray as a chemical hazard? Probably not. Yet, we use chemicals every day in our homes that are potentially hazardous.
Because we use more and more synthetic materials and spend so much time indoors, we are exposed to levels that are two to five times higher than they would be outdoors. New buildings and short-term activities, such as painting, can increase the levels by many hundred times.
So, what are hazardous materials? Remember, the word hazard stands for: danger or risk. This could apply to many substances, authorities, therefore, came up with four classifications:
- Corrosive material gradually destroys or damages other substances by chemical action. Examples are acids that clean rust from metal or unblock your drain.
- Anything that easily bursts into flames or explodes, such as petrol, kerosene, paint thinner, is classified as ignitable.
- Never mix household chemicals because they may be reactive. Mixing bleach with ammonia, for example, will form a hazardous gas.
- A material is said to be toxic when it contains a substance (poison) that may cause acute or chronic health problems in a person.
Please note that the classification system in your country may be different. A material may also have two or three classifications or it may alter its characteristics and change from one classification to another. For example, an acid is corrosive but may also be toxic if inhaled or swallowed.
The term volatile organic compounds has become the buzzword for people concerned with pollution – outdoors and indoors.
You probably have heard of or read about volatile organic compounds (VOC’s). Let me briefly explain what a VOC is. Volatile means that the substance easily evaporates at normal temperatures, such as a perfume. A substance is organic when the molecules contain carbon, that means it is derived from a natural source such as petroleum. And a compound is something that has two or more elements. Air, for example, is compounded chiefly of nitrogen, oxygen and trace gases.
VOC’s are chemicals that are common in many household products. We use chemicals to hide bad odour or to stimulate the sense of smell, as we do with perfumes, air fresheners and all the other many scented products. We use chemicals to control or kill other sources of indoor air pollution – biological contaminants. We scrub the mould with fungicide or kill the cockroach with insecticide. We combat bacteria and viruses in kitchen and bathrooms with chemical disinfectants. We use chemicals in our leisure times, when we stick parts together with glue, or when we decorate the home with a fresh coat of paint. We build and furnish our homes with materials that contain chemicals, such as particle boards and carpets.
I’m sure you can think of so many more things or activities that contain VOC’s, but for the moment just let’s say: they are everywhere. Fortunately, we can take steps to reduce VOC levels in indoor air, or, even better, use alternatives that don’t emit any or less hazardous gases. But first let’s see what VOC’s can do to our health and look at some common chemicals in detail.
Health Effects of Chemical Exposure
I begin this section with a quote from The chemical connection, by Louise Samways, a clinical psychologist and recognized expert in psychological healing and health:
“I would estimate that at least thirty percent of people, and probably more, suffer from significant food/chemical sensitivities affecting their psychological performance and emotional behavior. This means that in the average at least ten children [per classroom], including those with more obvious traditional allergies, are having their educational achievement and social development affected by the chemicals they breathe and the food they eat.”
“In the classroom these children are described as either lazy, too active, lethargic, irritable, talkative, easily distracted, naughty, aggressive, noisy, sulky, immature and nuisances.”
The effects that chemicals have on human psychology and emotion aren’t easily proven scientifically and, as Louise Samways probably would agree to, any form of proof can come only from years of observation and experience. Much more tangible, however, are the immediate medical symptoms a person may experience, such as eye, nose and throat irritation, headache, allergic skin reaction, dizziness, nausea, and difficulty breathing. In the long-term, continuous or frequent exposure to high doses may damage the liver, kidney or the central nervous system and cause cancer.
Scientists have some idea about what dose of a specific chemical is needed to trigger a certain reaction in humans. The tests, however, are very complicated, because the researchers have to consider factors, such as the length of exposure, the way a chemical is taken into the body (inhalation, ingestion, contact), the speed at which an individual absorbs the substance, and how it is metabolized.
That’s not all. Every person has a different level of sensitivity. One person may have to breathe in a generous squirt of insecticide before he or she shows any serious reaction. Another person may show effects after only a brief sniff of the chemical. It depends on the age of the person, the fitness level, the health standard in general, and whether the person abuses other substances, such as alcohol or nicotine. In general, a healthy person’s body is more tolerant to chemicals than the weakened body of a person with an underlying illness. Bulk also matters in this case. A child or a petite woman, for example, receives a comparatively higher dose of the same chemical than a hulk of a man. In addition, fatty tissue can store chemicals for a long time.
The indoor air chemicals may affect your sex life. Do I have your attention now? Well, that is at least what recent studies suggests. Some chemicals mimic human hormones that have the potential to adversely affect a person’s hormone balance. Scientists call them endocrine disrupters. Because your behavior and reproduction ability is regulated by hormones, the statement that this affects your sex life has just become very plausible. The decline in sperm counts over the last fifty years has led one research project to the conclusion that environmental chemicals have to take some of the blame. I need to point out, though, that these studies are inconclusive at this stage, but the US EPA warns that negative effects of endocrine disrupters cannot be ruled out.
Another recent study claims that chemicals in indoor air could also be a factor in Sudden Infant Death Syndrome (SIDS). Infants may become sensitized either before birth to the same chemicals the mother is exposed to, or after birth to airborne chemicals in the home environment. The latter shouldn’t surprise me, because I was also guilty of decorating a nursery for our new-born son, with a fresh layer of paint, light blue of course, and with a new carpet, new baby furniture, new blankets, and so on. In other words, I created an environment that, although it looked very friendly and inviting, was probably hostile to the developing body of an infant. Now I know that I should have de