background
canal
chemical
city
contaminated
contamination
danger
dirty
disaster
dump
eco
ecological
ecology
environment
environmental
factory
fatal
flowing
garbage
global
green tone
harmful
human
industrial
industry
lake
life
liquid
nature
plastic
poison
pollute
polluted
pollution
problems
recycle
responsibility
river
rubbish
rusty
sea
sewage
steam
stream
substance
tainted
toxic
trash
unhygienic
urban
waste
water