PLUMBUM — LEAD 423 



from paint buckets thrown upon the ground, paint buckets or re- 

 cently painted trqughs, and buildings. Men frequently become 

 poisoned by handling the lead salts, or by using them in the arts 

 (painters). Lead salts are present in some wall papers and tinned 

 goods are sometimes dangerous if there is too large a percentage of 

 lead in the solder or upon the tins. 



Toxic Doses. This has not been well established, and varies 

 greatly with the species of animal, idiosyncrasy, general condition 

 and preparation of lead given. Lander gives the foUovdng provi- 

 sional figures for minimum fatal doses of lead acetate : 



Horse T500 grains 

 Cow T20 grains 

 Sheep 450 grains 



Some of the lead used in paint (carbonate) must be much more 

 toxic because there are records of fairly small amounts causing death 

 in cattle. 



Horses are relatively resistant to lead and very few cases of 

 lead poisoning have been noticed among them. Cattle, on the other 

 hand, are quite susceptible. The different species are most suscepti- 

 ble in the following order : cattle, pigs, sheep, dogs, horses. 



Symptoms of Poisoning. Acute. This results from a single 

 large dose and the symptoms are those of gastroenteritis as men- 

 tioned above, and are entirely due to local corrosive action. « There 

 may be some nervous disturbances as stupor, coma, delirium, or 

 muscular tremors. 



Chronic Lead Poisoning or Plumhism. This is remarkable from 

 the standpoint of length of time which the sickness may last. Cases 

 are on record where animals survived for 58 weeks. It usually ex- 

 tends over several weeks or months. The usual symptoms are those 

 of gastrointestinal disorder, with lead line on the giims, constipa- 

 tion or diarrhea, loss of appetite, thirst and tucked up abdomen. 

 The nervous system is also extensively involved. This is shown by 

 paralysis of the extensors of the extremities so that the animals 

 stand upon the knees in front and toes behind. Besides this there 

 may be general paralysis, convulsions, anesthesia, dizziness, tremors^ 

 delirium, coma and blindness. The general symptoms are anemia, 

 short breathing, emaciation, acceleration of the pulse, edema and 

 interstitial nephritis. The paralysis is usually considered as due to 

 peripheral neuritis and the delirium, convulsions, etc., to some ac- 

 tion upon the brain or cord. Colic and constipation which are 

 common symptoms in man, are rarely observed in animals. 



Lesions. In acute poisoning there is usually evidence of cor- 

 rosion. Particles of lead may also be found in the stomach or in- 

 testines of the animals. Frequently pieces of lead paint will be 



