Lead Poisoning

Abstract

Examination of the records of patients with lead poisoning admitted to the Children's Hospital of Philadelphia revealed a seasonal incidence in the onset of encephalopathic symptoms. Figure 1 shows the monthly distribution of onset of symptoms of the patients with frank lead encephalopathy admitted to this hospital.In constructing this figure only patients with frank encephalopathic symptoms of rather acute onset were counted; patients with latent or subclinical plumbism, usually discovered accidentally, who exhibited no obvious encephalopathic symptoms were not included. It is apparent from figure 1 that almost all of the cases occur during the late spring and summer months. Shelling and Hopper 1 commented on the same seasonal incidence of the cases studied in the Harriet Lane Home.We assumed that there was a real relation, probably causal, between the summer season and the increased severity of lead poisoning and planned experiments to examine the seasonal factors which were possibly operative in determining this relation. In this investigation a study was made of the effect of two meteorologie phenomena, increased temperature and increased solar radiation, which occur during the summer season on the severity of lead poisoning in rats. EXPERIMENTAL STUDYAlbino rats raised in our laboratory colony were used in all experiments. Rats weighing in the neighborhood of 60 to 100 Gm. were selected, for we had found that it was difficult to produce appreciable poisoning in heavier animals

Photohemolysis. The Comparative Behavior of Erythrocytes from Patients with Different Types of Porphyria

“…Other effects of light in lead poisoning have been noted. Acutely poisoned rabbits excreted even greater amounts of coproporphyrin following exposure to ultraviolet light ( 12), perhaps related is the higher incidence of clinical lead poisoning appearing in the summer months ( 13). Other diseases of porphyrin metabolism, porphyria cutanea tarda and South African porphyria, are characterized by lightinduced skin symptoms with normal red cell porphyrins.…”

Lead Poisoning

“…A number of workers including Rapoport and Rubin (1941) have shown that in the great majority of cases symptoms appear during the late spring and summer months. This has been attributed to sunlight causing increased absorption of metal from the bowel, the intake and mobilization of lead being intimately related to calcium metabolism, while experimental work has shown that vitamin D has no effect on poisoning by inhalation.…”