One common fire retardant additive is bromine, which is great at keeping the plastic from burning, but not so great at resistance to UV light. The bromine breaks down and becomes free radicals ...

Bromine water is an orange solution of bromine. It becomes colourless when it is shaken with an alkene. Alkenes can decolourise bromine water, but alkanes cannot. The slideshow shows this process.

Recent research indicates that black plastic found in items like food containers ... Out of 203 products tested, 20 had high levels of the chemical bromine. Of those, about 85% of products ...