Phosphoric acid is used in fertilizers as its salts, in dyeing and sugar and oil refining. It is used as an electrolyte, in semiconductors and as a chelant in household cleaners. Phosphoric acid has many applications. Due to its non-toxic and mildly acidic nature, it is used in food flavoring, beverages, dental products, cosmetics, and skin care products. Industrially, it is used mainly in the production of phosphate fertilizers.Phosphoric acid. Phosphoric acid, also called orthophosphoric acid, (H3PO4), the most important oxygen acid of phosphorus, used to make phosphate salts for fertilizers. It is also used in dental cements, in the preparation of albumin derivatives, and in the sugar and textile industries.