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toxic - adj. containing poisonous substances; poisonous
lead - n. a heavy and soft metal that has a gray color
asbestos - n. a soft gray mineral that does not burn, that was used especially as a building material in the past, and that can cause serious diseases of the lungs when people breathe its dust
compound - n. a substance created when the atoms of two or more chemical elements join together
backyard - n. the general area near and around someone's home
pesticide - n. a chemical that is used to kill animals or insects that damage plants or crops
contaminant - n. something that makes a place or a substance such as water, air, or food no longer suitable for use
