Answer:

PCBS

Answer	Crossword Clue
PCBS	They were banned by Congress in 1977
PCBS	Banned pollutants
PCBS	Landfill toxins

PCBS	Some EPA targets
PCBS	Banned chemicals, for short
PCBS	Banned pollutants, briefly
PCBS	Toxic pollutants
PCBS	Environmental toxins banned in 1975
PCBS	Toxins phased out by a 1975 law
PCBS	Double-benzene-ring pollutants
PCBS	Toxins banned in the '70s

PCBS	Environmental toxins (abbr.)
PCBS	Industrial pollutants banned in 1975
PCBS	EPA-banned chemicals
PCBS	Chem. contaminants
PCBS	Industrial compounds banned in the USA since the late '70s
PCBS	Pollutants banned since the '70s
PCBS	Hudson River pollutants, initially
PCBS	Environmental toxins

PCBS	Industrial pollutants
PCBS	They were banned in 1975
PCBS	Toxic chemical compounds in industrial waste, briefly
PCBS	Banned environmental toxins, for short
PCBS	Highly toxic environmental pollutants, for short
PCBS	Chem. pollutants
PCBS	Cancer-causing compounds
PCBS	Some pollutants

PCBS	Highly toxic pollutants
PCBS	Environmental toxins, for short
PCBS	Banned chemicals
PCBS	Dumpsite pollutants, for short
PCBS	Chemicals banned by Congress in '76
PCBS	E.P.A. targets
PCBS	Noxious compounds, briefly
PCBS	Potential landfill pollutants, for short

PCBS	Some coolant fluids, for short
PCBS	Environmental pollutants, for short
PCBS	They've been banned in the U.S. since '79
PCBS	Banned chemicals still found in the environment
PCBS	Toxic chem. pollutants