ADJ.
used
FLAME-RETARDANT + NOUN
chemicals
PREP.
on
adj
Hard to ignite; not supporting or conveying flame; tending to curtail flames' spread.
noun
A substance used to make an object flameproof.
The flame-retardant used on the child's pajamas would keep them from bursting into flame, but it caused a rash.
adjective — resistant to catching fire
The U.S. Environmental Protection Agency has begun a major new risk assessment of 20 flame-retardant chemicals.