Chronic lead poisoning plays the most important rôle in industrial metallic poisoning, and indeed in industrial poisoning generally. The result everywhere where inquiry into industrial poisoning has been instituted has been to place the number of cases of lead poisoning at the top of the list; for one case of other forms of industrial poisoning there are twenty of lead.
In the last few years a very extensive literature and one not easily to be surveyed has grown up on the subject of chronic industrial lead poisoning. I cannot attempt as I have done with other forms of poisoning to do justice to all sources of literature on this subject.
As there is no obligation to notify industrial lead poisoning[B]—or indeed any form of industrial poisoning—in many countries, the most important source of information is wanting. Nevertheless more or less comprehensive inquiries as to the extent of the disease in general have been made in different countries and large cities which furnish valuable data.
An idea of the yearly number of cases of lead poisoning occurring in Prussia is given in the following statistics of cases treated in Prussian hospitals for the years 1895-1901:
| Year. | Males. | Females. | Total. |
|---|---|---|---|
| 1895 | 1120 | 43 | 1163 |
| 1899 | 1601 | 23 | 1624 |
| 1900 | 1509 | 14 | 1523 |
| 1901 | 1359 | 24 | 1383 |
The occupation of these cases was as follows:
| Year. | Metallic Lead. | White Lead. | Painters. |
|---|---|---|---|
| 1895 | 364 | 312 | 347 |
| 1899 | 551 | 310 | 460 |
| 1900 | 516 | 360 | 378 |
| 1901 | 498 | 282 | 339 |
About half the cases, therefore, are caused by use of white lead. The report of the sick insurance societies of the Berlin painters gives information as to the proportion treated in hospital to those treated at home, which was as 1:4.
The industries may be classified according to risk as follows[1] :