Parrish’s chemical food never contained arsenic

Editor—I have only recently seen the short item on the Minerva page submitted by Barrett.¹ It is illustrated by a colour photograph of a finely preserved bottle of Parrish’s chemical food, sold by A J Jull of The Pharmacy, Charlbury, Oxfordshire.

The caption to the photograph perpetuates a popular medical misapprehension—that the iron tonic Parrish’s food contained arsenic and was withdrawn from sale some 30 years ago. Having checked through the wealth of sources available in the library of the Royal Pharmaceutical Society of Great Britain, I can confirm that this was not the case. This may seem a minor historical point, but during the past few months I have received two inquiries from hospital doctors working in the field of skin cancers who were seeking to make a connection between arsenic supposedly ingested in Parrish’s food and the later development of basal cell carcinomas.

Parrish’s food is named after its inventor, Professor Edward Parrish, a pharmacist in Philadelphia who died in 1872. The first published description of the compound seems to have been in Parrish’s own Introduction to Practical Pharmacy, published in 1856,² which ran into several further editions, later appearing as A Treatise on Pharmacy. The formula for the food was given in the 1859 edition as protosulphate of iron, phosphate of soda, phosphate of lime, phosphoric acid, carbonate of soda, carbonate of potassa, muriatic acid, water of ammonia, powdered cochineal, water, sugar, and orange-flower water. There is no mention of arsenic, and I can find no evidence of its having been an ingredient of any later variants of the product used in the United Kingdom.

Syrupus Ferri Phosphatis Compositus, with quoted synonyms Chemical Food and Parrish’s Syrup, appears in the first edition of Martindale’s The Extra Pharmacopoeia of Unofficial Drugs and Chemicals and Pharmaceutical Chemicals, published in 1883.³ This publication, now in its 31st edition, is still produced by the Pharmaceutical Press. Parrish’s Syrup and the synonymous Parrish’s Food were listed until the 1982 edition. The compound appears, again with no arsenic, in all editions of the British Pharmaceutical Codex published by the Pharmaceutical Society and Pharmaceutical Press between 1907 and 1968. Researchers are welcome to consult these sources and other supporting material in the library of the Royal Pharmaceutical Society of Great Britain, by appointment with me.