Cited by Medicus, 'Aluminium Food Containers: Are they Injurious?' Our Dogs 91 (23rd June 1933), pp. 902-903.
Description:

'A matter of general interest to dog owners has come under my notice in a pamphlet which has reached me for review, entitled “Chronic Poisoning by Aluminium and its Alloys” by Leo Spira, M.D., with a foreword by Professor Dr. Hans Horst Meyer, of the University of Vienna. (London: John Bale, Sons and Danielson, Ltd., Great Titchfield Street. 2s. 6d. net.).

The author is concerned primarily with human circumstances, and his pamphlet communicates the results of his observations over a period of ten years. According to Professor Meyer, in the “foreword.” Dr. Spira, in studying the subject of chronic poisoning, has recognised, as a hitherto hardly considered source of this chronic poisoning, the use of aluminium utensils in the kitchen. In the course of his investigations into the subject, Dr. Spira reveals details of a large number of experiments upon the effect of the use of aluminium vessels upon children and adults; and also upon dogs, cats, and other animals. The latter appear to have been carried out over a long period of years under the observation of Professor Meyer himself. Apparently what was being done aroused attention in medical circles in England, France, Germany, Switzerland, and the United States. As a result two sets of opinions developed, which were diametrically opposed to each other. On the one hand, the opinion has been expressed that, as a result of scientific investigation on animal anf [sic] man, aluminium has been found to be innocuous. On the other hand it was claimed with equal emphasis that scientific investigation had proved aluminium to be definitely poisonous. Between the parties were those that declared that although it was in general harmless, aluminium was found to be detrimental in some cases. Even the correctness of methods employed in laboratory analyses, and the value of the chemical and physiological experiments and pathological findings were disputed.

Accordingly Dr. Spira took the matter up, and his conclusions are embodied in the pamphlet now under review. Apparently some of the scientists in Germany held the view that aluminium derived from artificially aluminised food was either not soluble, and therefore not absorbed at all, or only in minute quantities which were perfectly harmless to the body, and that since there was no absorption there was no deposition of the element in the tissues. They contended that the amount of aluminium in aluminised food was very small in comparison with that taken regularly in the great variety of articles of food which contained it as a natural constituent. On the other hand, other scientists (in America) found that aluminium phosphate was dissolved by the hydrochloric acid of the gastric juice; that the aluminium chloride, thus formed owing to its astringent and protein precipitating properties, attacked the mucuos membrane of the stomach, passed from the alimentary canal into the blood circulation, and, without manifesting any tendency to accumulate in the blood, was deposited to some extent in various parts of the body, whereas another part was excreted in both the bile and the urine. This conversion of the aluminium phosphate into the chloride under the influence of the hydrochloric acid of the gastric juice was demonstrated in the excellent experiments made on animals by French investigators. They, too, showed that aluminium was absorbed, in comparatively large amounts, into the blood circulation and deposited in the tissues of the body. Animals fed on aluminised food gained weight more slowly than control animals. The younger they were, the more sensitive were they to aluminium. They suffered from severe diarrhoea immediately after being fed on aluminised food, and showed a definite retardation of reproduction. The anatomical changes produced by aluminium were demonstrated by various serious symptoms, such as congestion of the mucous membrane of the intestine, and (in females) atrophy of the ovaries.

In a very comprehensive series of animal experiments undertaken by the American physiologist Underhill and his assistants, it was found that the aluminium content of the blood tended to increase after ingestion of aluminised food. Aluminium was deposited in the various tissues, and the main places of storage were the liver, kidneys, brain, spleen, and muscles. The bile and spleen contained nearly eight times, the brain more than five and a half times, and the liver and kidneys more than four times as much aluminium per unit as the blood. On examining the tissues of dogs of different ages they ascertained that there existed a direct relationship between the age of the animal and the quantity of aluminium stored in the tissues, and that this same tendency for aluminium content to increase with advancing age existed in man.

In the aluminium poisoning produced in experimental animals, loss of appetite was noticed as the first symptom. They soon appeared inactive and depressed and lay quietly in their cages, manifesting no interest in their surroundings; and if forced to move, were slow and clumsy. In addition, on feeding dogs for twelve weeks on aluminised food, a skin disease developed in one of the animals, which was covered with abscesses that became large bleeding sores. When given milk, a quart at a time, by stomach tube for a few days, improvement started at once; by the end of the experiment it was eating all its food, the skin had healed, and new hair was growing. The post-mortem revealed marked congestion in all the viscera. The stomach was greatly distended, the parts somewhat swollen and containing a [sic] pin-point to pin-head-sized haemorrhages. In some animals the intestines were ulcerated and their contents greenish in colour. The liver showed extensive tissue changes, consisting of congestion, central necrosis, and fatty infiltration, and the kidneys pale and soft.

Summarising his conclusions, Dr. Spira says that it is impossible to minimise or consider as valueless finding which have been arrived at after most careful and painstaking researches. The chemical [902-903] properties of aluminium seem to, however, be established beyond dispute. It is readily attacked by acids and soluble in alkalies [sic]. It is attacked slowly by cold [ascetic] acid, but the rate of attack increased markedly with rising temperature and with progressive dilution of the acid. It is attacked with great rapidity by hydrochloric acid. The metal is attacked even by fairly pure atmospheric air, and all the more readily by impure air such as that in large industrial cities. It is readily soluble in alkalies [sic], alkaline water, and water to which alkalies [sic] or soap have been added. The blackening or corrosion of aluminium kitchen utensils is often traced to alkalis which have come in contact with them. It would, therefore, not be surprising to expect that, in the process of preparing food, the constituents of the aluminium alloys and also their chemical constituents should be set free, so as to contaminate the food.

The general suggestion, therefore, appears to be that aluminium food vessels may cause intestinal troubles both in man and animal. I do not profess to know to what extent such vessels are in use amongst dog-owners, but the subject is one not unworthy of their attention.' (902-903)