accident

animal

canal

coastline

contaminated

danger

dangerous

dead

death

decay

dirty

disaster

disease

disposal

ecological

ecology

ecosystem

emission

environment

environmental

epidemic

fish

float

fly

garbage

harmful

infection

lake

lying

nature

ocean

poison

poisoned

polluted

pollution

pond

problem

river

rotten

salmon

sea

sewage

smell

stink

toxic

tragedy

unhygienic

waste

wastewater

water