Our Backyard: What kind of chemicals do you use?

    Every now and then you hear that a school or business was evacuated because of a “hazardous” chemical spill. Occasionally, we read about a newly discovered “toxic” waste site.
    The terms “hazardous” and “toxic” are bantered about in the press, but what do they really mean? Do they have any relevance to routine, everyday life?
    They do when you consider the amount of chemicals we regularly buy, use and keep on hand for future projects. In very general terms, a hazardous material (it’s a waste if you can’t use it) is one that meets one or all four of the following criteria. It can easily ignite and burn. It is corrosive and can cause chemical burns. It can explode or cause a rapid and violent reaction. It can be toxic causing adverse biological effects, such as cancer, in an organism.
    Simply put, it can cause physical or biological harm. “Ignitable” materials include gasoline and alcohol. “Corrosive” materials include sulfuric acid and some oven cleaners. “Reactive” materials include sodium hypochlorite (a swimming pool chemical). Many of these are right at home in Maine households.
    A waste or material that is hazardous due to its toxicity such as pesticides or cleaning solvents may be “acute”, having an immediate effect after brief exposure, or “chronic”, where the effects occur sometime after the exposure. The problems may also be non-cancerous or cancerous.
    How do you find out if the chemicals, that you come in contact with, are hazardous or toxic and have acute or chronic effects?
    Read the labels on the containers or ask the manufacturer for the Material Safety Data Sheets (MSDS), which by law must contain all this information. These sheets also provide you with basic information about chemical composition, proper handing and the kinds of protective equipment that should be used.
    Knowing the hazards associated with improper use or prolonged exposure to chemicals can help you judge your risk from the point of purchase. You may simply decide that no exposure is best. While our society is hooked on the convenience of chemicals, we are still learning about the risks associated with many of them. In general, when it comes to potentially hazardous chemicals, the less exposure the better.
    One way to ensure less exposure is to seek out less toxic alternatives to home use products. Another is to use all chemicals with care. And, if you know you have potentially harmful materials taking up space in your basement or garage, take advantage of local household waste collection projects.
    This column was submitted by David McCaskill, an environmental engineer with the Maine Department of Environmental Protection’s Bureau of Remediation and Waste Management.