Nearly half of Americans breathing in unsafe levels of air pollutants-report (Vocab)

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soot (n)

a black powder produced when coal, wood, etc. is burned

smog (n)

air pollution caused by smoke or chemicals mixing with fog

sweeping (adj)

affecting many things, people; large

rollback (n)

the act of reducing and reserving the effect of a particular arrangement

premature (adj)

happening or done too soon; esp. before the natural suitable time

array (n)

a large number of products of similar types

asthma (n)

a chest disease in which breathing can become difficult, often caused by an allergic reaction

impaired (adj)

less effective than it should be, or is damaged

preterm (adj)

born before the full period of pregnancy is completed