Zinc borate is often combined with aluminum trihydroxide and used to substitute for antimony trioxide.

This is in particular true with respect to the inorganic compounds aluminum trihydroxide and magnesium hydroxide.

(b) The group of inorganics contains aluminium trihydroxide, magnesium hydroxide, ammonium polyphosphate, red phosphorus and zinc borate

Also the German alternatives report describes the use of aluminum trihydroxide as a flame retardant as “unproblematic.”

Halogen-free rubber cables can contain aluminium trihydroxide and zinc borate as flame retardant alternatives and incorporate the ethylene vinyl acetate polymer as well.

Concerning chemical substitutes and technical alternatives reported data (although not specifically related to Hexabromobiphenyl but as overall alternatives to brominated flame retardants) show that there are less hazardous alternatives e.g. aluminium trihydroxide.

Aluminum trihydroxide is the most frequently used flame retardant (Danish EPA, 1999). Due to an endothermic reaction when decomposing and other properties it is highly effective and also suppresses smoke.

Due to the low price of aluminum trihydroxide alternative materials may not be more expensive than BFR containing materials, but magnesium containing materials will usually be significantly more expensive.

Concerning chemical substitutes and technical alternatives reported data (although not specifically related to HBB but as overall alternatives to brominated flame retardants) show that there are less hazardous alternatives e.g. aluminium trihydroxide.