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monitor – v. to watch, observe, listen to, or check (something) for a special purpose over a period of time
pollutant – n. a substance that makes land, water, air, etc., dirty and not safe or suitable to use : something that causes pollution
fumes – n. smoke or gas that smells unpleasant — usually plural
asthma – n. a physical condition that makes it difficult for someone to breathe
chronic – adj. continuing or occurring again and again for a long time
bronchitis – n. an illness in which your bronchial tubes become sore or damaged and you cough a lot
premature – adj. happening too soon or earlier than usual
