Gentlemen,—My attention has been called to an article in your issue of the 19th January, under the head “Correspondence,” by Mr. Thomas Sutton, containing several statements with reference to carbolic acid which it would be wrong to allow to remain uncontradicted.
First: he says carbolic acid is by no means a good antiseptic, and is very poisonous, and then refers to persons being lately poisoned by its fumes at Wolverhampton.
As to its poisonous nature: It is, of course, a poison if taken internally in quantity, but is not a virulent one taken in any reasonable or probable quantity. It is, perhaps, not out of place to say that if it should be taken internally in a concentrated form, by misadventure, large doses of castor and sweet oil immediately administered will materially counteract the poisonous effect of the acid. The fumes of the acid are perfectly harmless and may be breathed with impunity.
Mr. Sutton is labouring under a false impression with regard to the case to which he alludes at Wolverhampton, of which the following is the correct account:—Two dogs (not human beings) were supposed to have died from inhaling the fumes of carbolic acid emanating from a disinfecting powder sprinkled over the floor of a workshop in Wolverhampton, and, the following is an extract from the report of the chemist who examined one of the dogs:—“The disinfecting powder was not a carbolic acid powder, but an imitation; for it contained nothing but lime impregnated with tar, and was entirely innocent of any harm to the animals. Strychnine, however, was discovered in considerable quantity in most parts of the viscera and in the blood. I calculated that at least one grain and a-quarter of this poisonous alkaloid had been administered to the animal by some evil-disposed person or persons unknown.” Thus much for the poisoning of human beings lately at Wolverhampton by the fumes of carbolic acid.[[4]]
[4]. The cattle show at the Agricultural Hall, Islington, has for the two last years been successfully disinfected and kept sweet with carbolic acid.
Had Mr. Sutton ever seen carbolic acid fumigation, or read about carbolic acid, he would not have made an assertion so utterly groundless. The writer has himself many times been for two or three days together in a room containing a large excess of carbolic acid fumes without experiencing any injurious effects.
With regard to the action of carbolic acid on the teeth, if Mr. Sutton will refer to an article in the British Journal of Dental Science for March, 1871, he will find “it is a powerful antiseptic, and invaluable for the arrest of any decay or decomposition of the teeth.”
Mr. Sutton has quoted from a long letter of Dr. Dougall’s to the Lancet, and I cannot do better than refer him to Dr. Sansom’s able reply to it in the Lancet of January 13th. Dr. Sansom says that the white-cloud appearance in albuminous solutions to which carbolic acid has been added is often really no albuminous precipitate at all, but is caused by refractile globules of carbolic acid in a fine state of sub-division; also, that it has been shown that albuminous solutions are antisepted when carbolic acid exists in them in too feeble a proportion to cause any precipitate whatever. If carbolic acid acted as an antiseptic by coagulating albumen, agents which had a greater coagulating power would, a fortiori, be more powerful antiseptics, which has abundantly been proved not to be the case, and therefore the antiseptic properties of carbolic acid do not result solely from its power of coagulating albumen.
With respect to the assertion that the amount of carbolic acid vapour which could be tolerated in the air of a hospital ward would be entirely inadequate to act as a disinfectant, Dr. Sansom says his experiments have shown him that carbolised atmospheres are efficient in preventing putrefaction and the growth of mouldiness, and more so than atmospheres impregnated with chloride of lime or sulphurous acid.
Dr. Sansom objects to the experiments recorded by Dr. Dougall, since tar oil (a crude product weak in carbolic acid, and possessing little or no volatile disinfectant constituent), and McDougall’s powder (a mixture of sulphites of lime and magnesia with tar oil) were used.