acid
air
atmosphere
breathe
changing
chemical
chimney
climate
cloud
cloudy
coal
damage
deleterious
dirty
ecological
ecology
emissions
energy
environment
factory
fuel
fumes
gas
global
growth
harmful
health
high
industrial
industry
intoxication
nature
pipe
plant
pollution
power
problems
refinery
sky
smog
smoke
smokestack
stack
steam
technology
tower
toxic
vapor
warming
white