acid
ash
ash particles
atmosphere
carbon dioxide
carbon monoxide
changing climate
chimney
climate
coal
contamination
danger
dark smoke
dense
dense dark cloud
dust
ecology
electric
electricity
emission
energy
environment
environmental
factory
fossil fuel
fuel
fume
global warming
grey
harmful
health risk
industrial
methane
ozone
pollution
power
power plant
power station
produce
production
refinery
risk
smog
smoke
smoke stack
stack
tower
toxic
warming