Do eco-friendly fireworks exist?

While you're looking up at the incredible firework display above you, take a moment to think about the effect it is having on the atmosphere.


Asked by: Stuart Taylor, by email

Environmentally-friendly fireworks have been developed to reduce the amount of atmospheric pollution produced. Traditional fireworks are normally made using a charcoal and sulphur fuel, a perchlorate oxidiser to help with burning, plus binders, colourants and propellants. When ignited, the pyrotechnics are spectacular, but they emit large amounts of smoke, unused perchlorates and metal by-products from the colourants, all of which are contaminates.

Eco-friendly fireworks have a clean burning, nitrogen-based fuel. This means a perchlorate oxidiser is not needed and because there is little smoke, only small amounts of metal salts are needed to produce the brilliantly coloured flames.

Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.