 Chemicals cause from 2 to 11 % of all burns and contribute to as many as 30 % of burn @-@ related deaths . Chemical burns can be caused by over 25 @,@ 000 substances , most of which are either a strong base ( 55 % ) or a strong acid ( 26 % ) . Most chemical burn deaths are secondary to ingestion . Common agents include : sulfuric acid as found in toilet <unk> , sodium <unk> as found in <unk> , and halogenated <unk> as found in paint <unk> , among others . <unk> acid can cause particularly deep burns that may not become symptomatic until some time after exposure . <unk> acid may cause the breakdown of significant numbers of red blood cells . 
