STATISTICS OF PLUMBISM[A]
[A] Based mainly on reports received from certifying factory surgeons
during the ten years 1900-1909.
Classification of notified cases of lead poisoning was carried out
on practically the same lines between the years 1900 and 1909, and
comparison of the data so collected has interest, in view of their
large number--nearly 7,000--in respect of (1) increase or decrease in
recorded amount in each one of eighteen classes of industries; (2)
severity and number of attack--_i.e._, whether first, second, third, or
chronic; and (3) main symptoms.
Notification was first enjoined by Section 29 of the Factory and
Workshop Act, 1895, which subsequently, on consolidation of the Factory
Acts, became Section 73 of the Act of 1901. This enactment requires
every medical practitioner, attending on, or called in to visit, a
patient whom he believes to be suffering from lead poisoning contracted
in a factory or workshop, to notify the case forthwith to the Chief
Inspector of Factories at the Home Office; and a similar obligation
is imposed on the occupier of a factory or workshop to send written
notice of every such case to the certifying surgeon and inspector of
factories for the district. In form there is close similarity between
this section and that requiring notification under the Infectious
Diseases (Notification) Act; but whereas the symptoms of these diseases
are, within well-recognized limits, precise, in lead poisoning the
differential diagnosis has not infrequently to be made from a variety
of common ailments--headache, anæmia, rheumatism, abdominal pain; and
there is no precise standard of what constitutes lead poisoning.
The notification of the practitioner as a rule gives no information
beyond the belief that the case is one of lead poisoning. As a matter
of routine the notification is followed up by an inquiry by the
certifying surgeon and inspector to see whether regulations already in
force have been infringed in the particular work-place or not, and as
to how far there may have been contributory negligence on the part of
the sufferer. The data supplied on the surgeon’s report form the basis
of the tabulation[1]. Brief explanation is wanted of the method adopted
in classification. Cases represent all attacks reported within a year,
and not previously reported within the preceding twelve months, so as
to make the number of persons and cases in a year the same. Where the
interval between two reports on the same person was more than twelve
months, the fresh attack was again included. The number of such second
reports on persons already included in a return numbered 284 (4·2 per
cent.), and a portion of these certainly, probably not more than 100,
have been included twice or thrice in the total 6,638 cases. Cases in
which there was obvious error in diagnosis, or in which the opinion
of the certifying surgeon was very strongly against the diagnosis
(especially when the report had been made in the first instance by
the occupier alone, and not by a medical practitioner), were excluded
from the return. These numbered 458 (6·8 per cent.). Others, again,
where there was a strong element of doubt, but not to be regarded as
more than a difference of opinion between two medical men, were marked
doubtful and included. Of these there were 424 (6·3 per cent.).
The classification of industries was designed to represent the way in
which the poisoning may be supposed to originate from (_a_) lead fumes
(1 to 4), (_b_) handling metallic lead (5 and 6), (_c_) dust from lead
compounds (7 to 14), and (_d_) lead paint (15 to 17). We attach now
only slight importance to this attempt to define causation, as it will
appear from our survey that we regard almost all cases as the result of
inhalation either of fumes or dust.
The reports describe not only the particular attack, but also the
general condition of the patient at the time of the attack. Very
frequently a combination of symptoms--colic, anæmia, and varying
degree of paralysis--are described as present, and when this is the
case each one of them has been entered under the appropriate heading.
The total number of symptoms, therefore, greatly exceeds the number
of cases, but this does not affect the correctness of the estimate of
each one as a proportion on the total number reported. The reports do
not give detailed information such as can be gained from hospital
records. Especially is this the case with the symptoms of paralysis and
encephalopathy.
Table III. shows the number of reported cases included in returns for
each of the years 1900 to 1909. On the total figures there has been
a reduction of 47·7 per cent. In the several industries the salient
feature is that the considerable diminution achieved is limited to
industries--notably white lead, earthenware and china, litho-transfers,
and paints and colours--in which, under regulations or special rules,
locally applied exhaust ventilation for the removal of dust, and
periodical medical examination of the workers, have been required.
Where, owing to the nature of the processes carried on, it has been
found impracticable, in the present state of knowledge, to apply local
exhaust ventilation, and where periodical examination of the workers is
lacking, as in smelting of metals[A] and industries using paint, there
has been tendency to increase in the number of cases. In coach-building
the increase is in part due to activity in the motor-car industry.
[A] This is now required by the regulations dated August 12, 1911.
TABLE III.--NOTIFICATION OF POISONING BY LEAD (UNDER S. 73, 1901),
1900-1909.
+--------------------------+---------------------------------------
| | Reported
| +--------+-----+-----+-----+-----+-----+
| | Total | | | | | |
| Industry. |1900-09.|1909.|1908.|1907.|1906.|1905.|
+--------------------------+--------+-----+-----+-----+-----+-----+
| (1) | (2) | (3) | (4) | (5) | (6) | (7) |
|LEAD POISONING |6,762²⁷⁵|553³⁰|646³²|578²⁶|632³³|592²³|
| 1. Smelting of metals | 412¹⁸ | 66⁵ | 70² | 28² | 38¹ | 24¹ |
| 2. Brass works | 75⁴ | 5 | 6 | 9¹ | 11 | 5¹ |
| 3. Sheet lead and lead | | | | | | |
| piping | 109³ | 9² | 14 | 6 | 7 | 9 |
| 4. Plumbing and soldering| 217¹² | 28 | 27 | 20² | 16⁴ | 24² |
| 5. Printing | 200¹⁷ | 21¹ | 30² | 26³ | 16² | 19⁴ |
| 6. File-cutting | 211¹⁹ | 8 | 9² | 10 | 15 | 12 |
| 7. Tinning and enamelling| 138² | 21 | 10 | 25 | 18¹ | 14¹ |
| 8. White lead |1,295³¹ | 32² | 79³ | 71 |108⁷ | 90¹ |
| 9. Red lead | 108 | 10 | 12 | 7 | 6 | 10 |
|10. China and earthenware |1,065⁵⁷ | 58⁵ |117¹²|103⁸ |107⁴ | 84³ |
|10_a._ Litho-transfers | 48 | 1 | 2 | 10 | 5 | 5 |
|11. Glass cutting and | | | | | | |
| polishing | 48⁹ | 4² | 3¹ | 4 | 4¹ | 3 |
|12. Enamelling iron plates| 52¹ | 3 | 7 | 6 | 4 | 2 |
|13. Electric accumulators | 285⁶ | 27² | 25¹ | 21 | 26 | 27¹ |
|14. Paints and colours | 422⁷ | 39² | 25 | 35¹ | 37 | 57¹ |
|15. Coach-building | 697⁴¹ | 95⁶ | 70³ | 70³ | 85⁷ | 56³ |
|16. Ship-building | 269¹⁰ | 27¹ | 15 | 22¹ | 26¹ | 32² |
|17. Paint used in other | | | | | | |
| industries | 452¹⁸ | 42 | 47¹ | 49² | 37³ | 49² |
|18. Other industries | 659²⁰ | 57² | 78⁵ | 56² | 66² | 70¹ |
+--------------------------+--------+-----+-----+-----+-----+-----+
+--------------------------+-------------------------------+
| |Cases. |
| +-----+-----+-----+-----+-------+
| | | | | | |
| Industry. |1904.|1903.|1902.|1901.| 1900. |
+--------------------------+-----+-----+-----+-----+-------+
| (1) | (8) | (9) | (10)| (11)| (12) |
|LEAD POISONING |597²⁶|614¹⁹|629¹⁴|863³⁴|1,058³⁸|
| 1. Smelting of metals | 33¹ | 37² | 28 | 54³ | 34¹ |
| 2. Brass works | 10¹ | 15 | 5 | 6¹ | 3 |
| 3. Sheet lead and lead | | | | | |
| piping | 7 | 11 | 12 | 17 | 17¹ |
| 4. Plumbing and soldering| 21³ | 26 | 23¹ | 23 | 9 |
| 5. Printing | 15 | 13² | 19 | 23¹ | 18² |
| 6. File-cutting | 20⁴ | 24² | 27¹ | 46⁷ | 40³ |
| 7. Tinning and enamelling| 10 | 14 | 11 | 10 | 5 |
| 8. White lead |116² |109² |143¹ |189⁷ | 358⁶ |
| 9. Red lead | 11 | 6 | 13 | 14 | 19 |
|10. China and earthenware |106⁴ | 97³ | 87⁴ |106⁵ | 200⁸ |
|10_a._ Litho-transfers | 3 | 3 | 2 | 7 | 10 |
|11. Glass cutting and | | | | | |
| polishing | -- | 4 | 8² | 11³ | 7 |
|12. Enamelling iron plates| 3 | 4 | 3¹ | 9 | 11 |
|13. Electric accumulators | 33 | 28 | 16¹ | 49¹ | 33 |
|14. Paints and colours | 32¹ | 39¹ | 46 | 56 | 56¹ |
|15. Coach-building | 49⁴ | 74⁵ | 63¹ | 65⁴ | 70⁵ |
|16. Ship-building | 48 | 24¹ | 15¹ | 28¹ | 32² |
|17. Paint used in other | | | | | |
| industries | 27³ | 46¹ | 44¹ | 61 | 50⁵ |
|18. Other industries | 53³ | 40 | 64 | 89¹ | 86⁴ |
+--------------------------+-----+-----+-----+-----+-------+
The principal figures are those of the cases, fatal and non-fatal;
the small figures relate to fatal cases only.
For the sake of completeness the figures for the years 1910 and 1911
are given below. The grand totals are comparable with those for each
of the years 1900 to 1909, but not the total for all of the several
groups of industries. Thus, the name of heading No. 7 is altered to
“Tinning of metals,” and No. 12 to “Vitreous enamelling,” because
of regulations widening their scope, and now including cases which
previously figured in No. 18, “Other industries.”
+----------------------------------+-----+-----+
| Industry. |1911.|1910.|
+----------------------------------+-----+-----+
|LEAD POISONING |669³⁷|505³⁸|
| Smelting of metals | 48³ | 34⁵ |
| Brass works | 9¹ | 7 |
| Sheet lead and lead piping | 12 | 4 |
| Plumbing and soldering | 37² | 25¹ |
| Printing | 32² | 33⁴ |
| File-cutting | 18² | 9¹ |
| Tinning of metals | 13 | 17 |
| Vitreous enamelling | 19¹ | 17 |
| White lead | 41² | 34¹ |
| Red lead | 13¹ | 10 |
| China and earthenware | 92⁶ | 77¹¹|
| Litho-transfers | 1 | 1 |
| Glass cutting and polishing | 5 | -- |
| Electric accumulators | 24¹ | 31 |
| Paints and colours | 21 | 17¹ |
| Coach and car painting |104⁵ | 70⁶ |
| Ship-building | 36 | 21² |
| Use of paint in other industries| 56¹ | 51³ |
| Other industries | 88⁴ | 47³ |
+----------------------------------+-----+-----+
TABLE IV.--ANALYSIS OF REPORTS ON LEAD POISONING BY CERTIFYING SURGEONS
FROM JANUARY 1, 1900, TO DECEMBER 31, 1909.
+-----+--------------++-----------++--------------------------------++
| | || || Severity of Symptoms. ||
+-----+--------------++-----------++----------+----------+----------++
| | || || | | ||
| No. | Occupation. || Total. || Severe. | Moderate.| Slight. ||
+-----+--------------++-----------++----------+----------+----------++
| (1) | (2) || (3) || (4) | (5) | (6) ||
+-----+--------------++-----+-----++-----+----+-----+----+-----+----++
| | || M. | F. || M. | F. | M. | F. | M. | F. ||
| 1 |Smelting of || | || | | | | | ||
| |metals: || | || | | | | | ||
| |Cases || 411| --|| 104| -- | 105| -- | 197| -- ||
| |Per cent. || 100| --|| 25·3| -- | 25·6| -- | 47·9| -- ||
| 2 |Brass works: || | || | | | | | ||
| |Cases || 70| 4|| 26| 2| 20| 1| 22| 1||
| |Per cent. || 100| --|| 37·1| -- | 28·6| -- | 31·5| -- ||
| 3 |Sheet lead || | || | | | | | ||
| |and lead || | || | | | | | ||
| |piping: || | || | | | | | ||
| |Cases || 102| 4|| 25| 1| 29| 1| 47| 2||
| |Per cent. || 100| --|| 24·5| -- | 28·4| -- | 46·1| -- ||
| 4 |Plumbing and || | || | | | | | ||
| |soldering: || | || | | | | | ||
| |Cases || 186| 30|| 65| 6| 49| 6| 65| 16||
| |Per cent. || 100| 100|| 34·9|20·0| 26·3|20·0| 34·9|53·3||
| 5 |Printing: || | || | | | | | ||
| |Cases || 190| 6|| 55| -- | 43| 1| 82| 5||
| |Per cent. || 100| --|| 28·9| -- | 22·6| -- | 43·2| -- ||
| 6 |File-cutting: || | || | | | | | ||
| |Cases || 174| 34|| 85| 8| 34| 5| 48| 21||
| |Per cent. || 100| 100|| 48·9|23·5| 19·5|14·7| 27·6|61·8||
| 7 |Tinning and || | || | | | | | ||
| |enamelling of || | || | | | | | ||
| |hollow-ware: || | || | | | | | ||
| |Cases || 84| 53|| 26| 13| 27| 16| 31| 24||
| |Per cent. || 100| 100|| 31·0|24·5| 32·1|30·2| 36·9|45·3||
| 8 |White lead: || | || | | | | | ||
| |Cases ||1,167| 76|| 317| 27| 235| 11| 593| 33||
| |Per cent. || 100| 100|| 27·2|35·5| 20·1|14·5| 50·8|43·4||
| 9 |Red lead: || | || | | | | | ||
| |Cases || 108| --|| 30| -- | 31| -- | 45| -- ||
| |Per cent. || 100| --|| 27·8| -- | 28·7| -- | 41·7| -- ||
|10 |China and || | || | | | | | ||
| |earthenware: || | || | | | | | ||
| |Cases || 490| 572|| 102| 86| 158| 181| 216| 286||
| |Per cent. || 100| 100|| 20·8|15·0| 32·2|31·6| 44·1|50·0||
|10_a_|Litho- || | || | | | | | ||
| |transferers: || | || | | | | | ||
| |Cases || 20| 28|| 2| 5| 2| 8| 15| 15||
| |Per cent. || 100| 100|| 10·0|17·9| 10·0|28·6| 75·0|53·6||
|11 |Glass cutting || | || | | | | | ||
| |and polishing:|| | || | | | | | ||
| |Cases || 47| --|| 20| -- | 11| -- | 16| -- ||
| |Per cent. || 100| --|| 42·5| -- | 23·4| -- | 34·0| -- ||
|12 |Enamelling of || | || | | | | | ||
| |iron plates: || | || | | | | | ||
| |Cases || 38| 14|| 6| 6| 19| 4| 13| 3||
| |Per cent. || 100| 100|| 15·8|42·9| 50·0|28·6| 34·2|21·4||
|13 |Electric || | || | | | | | ||
| |accumulators: || | || | | | | | ||
| |Cases || 281| --|| 58| -- | 70| -- | 151| -- ||
| |Per cent. || 100| --|| 20·6| -- | 24·9| -- | 53·7| -- ||
|14 |Paint and || | || | | | | | ||
| |colour works: || | || | | | | | ||
| |Cases || 397| 21|| 111| 2| 104| 4| 176| 15||
| |Per cent. || 100| 100|| 27·9| 9·5| 26·2|19·0| 44·4|71·5||
|15 |Coach-making: || | || | | | | | ||
| |Cases || 678| 3|| 176| -- | 187| 2| 293| 1||
| |Per cent. || 100| --|| 26·0| -- | 27·6| -- | 43·2| -- ||
|16 |Ship-building:|| | || | | | | | ||
| |Cases || 261| -- || 93| -- | 51| -- | 108| -- ||
| |Per cent. || 100| -- || 35·6| -- | 19·5| -- | 41·4| -- ||
|17 |Paints used || | || | | | | | ||
| |in other || | || | | | | | ||
| |industries: || | || | | | | | ||
| |Cases || 405| 42|| 127| 11| 97| 7| 174| 22||
| |Per cent. || 100| 100|| 31·4|26·2| 23·9|16·7| 43·0|52·4||
|18 |Other || | || | | | | | ||
| |industries: || | || | | | | | ||
| |Cases || 528| 114|| 160| 37| 117| 22| 230| 52||
| |Per cent. || 100| 100|| 30·3|32·5| 22·2|19·3| 43·6|45·6||
| |Total cases ||5,637|1,001||1,588| 204|1,389| 269|2,522| 496||
| | „ per || | || | | | | | ||
| |cent. || 100| 100|| 28·2|20·4| 24·7|26·9| 44·7|49·5||
+-----+--------------++-----+-----++-----+----+-----+----+-----+----++
+-----+--------------++------------------------------++
| | || Number of Attack. ||
+-----+--------------++----------+---------+---------++
| | || | |Third, or||
| No. | Occupation. || First. | Second. | Chronic.||
+-----+--------------++----------+---------+---------++
| (1) | (2) || (7) | (8) | (9) ||
+-----+--------------++-----+----+----+----+----+----++
| | || M. | F. | M. | F. | M. | F. ||
| 1 |Smelting of || | | | | | ||
| |metals: || | | | | | ||
| |Cases || 276| -- | 65| -- | 64| -- ||
| |Per cent. || 67·2| -- |16·8| -- |15·6| -- ||
| 2 |Brass works: || | | | | | ||
| |Cases || 40| 3| 11| 1| 17| -- ||
| |Per cent. || 57·1| -- |15·7| -- |24·3| -- ||
| 3 |Sheet lead || | | | | | ||
| |and lead || | | | | | ||
| |piping: || | | | | | ||
| |Cases || 72| 3| 17| -- | 11| 1||
| |Per cent. || 70·6| -- |16·7| -- |10·8| -- ||
| 4 |Plumbing and || | | | | | ||
| |soldering: || | | | | | ||
| |Cases || 114| 22| 30| 1| 32| 3||
| |Per cent. || 61·3|73·3|16·1| 3·3|17·2|10·0||
| 5 |Printing: || | | | | | ||
| |Cases || 118| 6| 29| -- | 33| -- ||
| |Per cent. || 62·1| -- |15·3| -- |17·4| -- ||
| 6 |File-cutting: || | | | | | ||
| |Cases || 49| 24| 39| 4| 78| 6||
| |Per cent. || 28·2|70·6|22·4|11·8|44·8|17·6||
| 7 |Tinning and || | | | | | ||
| |enamelling of || | | | | | ||
| |hollow-ware: || | | | | | ||
| |Cases || 50| 31| 18| 16| 15| 6||
| |Per cent. || 59·5|58·5|21·4|30·2|17·9|11·3||
| 8 |White lead: || | | | | | ||
| |Cases || 961| 56| 108| 9| 49| 3||
| |Per cent. || 82·4|73·7| 9·3|11·8| 4·2| 3·9||
| 9 |Red lead: || | | | | | ||
| |Cases || 90| -- | 8| -- | 8| -- ||
| |Per cent. || 83·3| -- | 7·4| -- | 7·4| -- ||
|10 |China and || | | | | | ||
| |earthenware: || | | | | | ||
| |Cases || 297| 469| 91| 65| 87| 17||
| |Per cent. || 60·6|82·0|18·6|11·4|17·7| 3·0||
|10_a_|Litho- || | | | | | ||
| |transferers: || | | | | | ||
| |Cases || 17| 27| 2| -- | -- | 1||
| |Per cent. || 85·0|96·4|10·0| -- | -- | 3·6||
|11 |Glass cutting || | | | | | ||
| |and polishing:|| | | | | | ||
| |Cases || 21| -- | 9| -- | 17| -- ||
| |Per cent. || 44·7| -- |19·1| -- |36·2| -- ||
|12 |Enamelling of || | | | | | ||
| |iron plates: || | | | | | ||
| |Cases || 31| 11| 7| 2| -- | -- ||
| |Per cent. || 81·6|78·6|18·4|14·3| -- | -- ||
|13 |Electric || | | | | | ||
| |accumulators: || | | | | | ||
| |Cases || 222| -- | 40| -- | 13| -- ||
| |Per cent. || 79·0| -- |14·2| -- | 4·6| -- ||
|14 |Paint and || | | | | | ||
| |colour works: || | | | | | ||
| |Cases || 290| 16| 61| 3| 39| 2||
| |Per cent. || 73·1|76·2|15·4|14·3| 9·8| 9·5||
|15 |Coach-making: || | | | | | ||
| |Cases || 405| 2| 127| -- | 114| 1||
| |Per cent. || 59·8| -- |18·7| -- |16·8| -- ||
|16 |Ship-building:|| | | | | | ||
| |Cases || 181| -- | 41| -- | 24| -- ||
| |Per cent. || 69·0| -- |15·7| -- | 9·2| -- ||
|17 |Paints used || | | | | | ||
| |in other || | | | | | ||
| |industries: || | | | | | ||
| |Cases || 238| 36| 83| 4| 71| 1||
| |Per cent. || 58·8|85·7|20·5| 9·5|17·5| 2·4||
|18 |Other || | | | | | ||
| |industries: || | | | | | ||
| |Cases || 329| 93| 85| 14| 86| 5||
| |Per cent. || 62·3|81·6|16·1|12·3|16·3| 4·4||
| |Total cases ||3,800| 799| 871| 119| 758| 46||
| | „ per || | | | | | ||
| |cent. || 67·4|79·8|15·5|11·9|13·4| 4·6||
+-----+--------------++-----+----+----+----+----+----++
+-----+--------------++------------------------------------------
| | || Main Symptoms.
+-----+--------------++----------+----------+---------+----------
| | || | | |
| No. | Occupation. || Gastric. | Anæmia. |Headache.| Paretic.
+-----+--------------++----------+----------+---------+----------
| (1) | (2) || (10) | (11) | (12) | (13)
+-----+--------------++-----+----+-----+----+----+----+-----+----
| | || M. | F. | M. | F. | M. | F. | M. | F.
| 1 |Smelting of || | | | | | | |
| |metals: || | | | | | | |
| |Cases || 325| -- | 99| -- | 18| -- | 99| --
| |Per cent. || 79·1| -- | 24·1| -- | 4·4| -- | 24·1| --
| 2 |Brass works: || | | | | | | |
| |Cases || 57| 4| 28| 3| 16| 3| 28| 2
| |Per cent. || 81·4| -- | 40·0| -- |22·9| -- | 40·0| --
| 3 |Sheet lead || | | | | | | |
| |and lead || | | | | | | |
| |piping: || | | | | | | |
| |Cases || 82| 2| 28| 1| 9| 1| 26| 2
| |Per cent. || 80·4| -- | 27·5| -- | 8·8| -- | 25·5| --
| 4 |Plumbing and || | | | | | | |
| |soldering: || | | | | | | |
| |Cases || 146| 25| 58| 14| 23| 10| 46| 7
| |Per cent. || 78·5|83·3| 31·2|46·7|12·4|33·3| 24·7|23·3
| 5 |Printing: || | | | | | | |
| |Cases || 144| 6| 41| 3| 22| 1| 36| --
| |Per cent. || 75·8| -- | 21·6| -- |11·6| -- | 18·9| --
| 6 |File-cutting: || | | | | | | |
| |Cases || 104| 23| 50| 17| 15| 2| 80| 3
| |Per cent. || 59·8|67·7| 28·7|50·0| 8·6| 5·9| 46·0| 8·8
| 7 |Tinning and || | | | | | | |
| |enamelling of || | | | | | | |
| |hollow-ware: || | | | | | | |
| |Cases || 65| 49| 33| 12| 9| 3| 19| 13
| |Per cent. || 77·4|92·5| 39·3|22·6|10·7| 5·7| 22·6|24·5
| 8 |White lead: || | | | | | | |
| |Cases ||1,003| 59| 286| 8| 51| 5| 120| 7
| |Per cent. || 85·9|77·6| 2·5|10·5| 4·4| 6·6| 10·3| 9·2
| 9 |Red lead: || | | | | | | |
| |Cases || 87| -- | 28| -- | 8| -- | 14| --
| |Per cent. || 80·6| -- | 25·9| -- | 7·4| -- | 13·0| --
|10 |China and || | | | | | | |
| |earthenware: || | | | | | | |
| |Cases || 318| 430| 93| 183| 78| 181| 147| 79
| |Per cent. || 64·9|75·2| 19·0|32·0|15·9|31·6| 30·0|13·8
|10_a_|Litho- || | | | | | | |
| |transferers: || | | | | | | |
| |Cases || 16| 25| 2| 8| 6| 14| 1| 8
| |Per cent. || 80·0|89·3| 10·0|28·6|30·0|50·0| 5·0|28·6
|11 |Glass cutting || | | | | | | |
| |and polishing:|| | | | | | | |
| |Cases || 28| -- | 9| -- | 2| -- | 14| --
| |Per cent. || 59·6| -- | 19·1| -- | 4·2| -- | 29·8| --
|12 |Enamelling of || | | | | | | |
| |iron plates: || | | | | | | |
| |Cases || 37| 8| 3| 5| 2| 2| 3| 3
| |Per cent. || 97·4|57·1| 7·9|35·7| 5·3|14·3| 7·9|21·4
|13 |Electric || | | | | | | |
| |accumulators: || | | | | | | |
| |Cases || 255| -- | 70| -- | 10| -- | 34| --
| |Per cent. || 90·8| -- | 24·9| -- | 3·6| -- | 12·1| --
|14 |Paint and || | | | | | | |
| |colour works: || | | | | | | |
| |Cases || 344| 19| 121| 8| 36| 2| 81| 1
| |Per cent. || 86·7|90·5| 30·5|38·1| 9·1| 9·5| 20·4| 4·8
|15 |Coach-making: || | | | | | | |
| |Cases || 537| 2| 178| -- | 109| -- | 157| 1
| |Per cent. || 79·2| -- | 26·3| -- |16·1| -- | 23·2| --
|16 |Ship-building:|| | | | | | | |
| |Cases || 207| -- | 77| -- | 27| -- | 54| --
| |Per cent. || 79·3| -- | 29·5| -- |10·3| -- | 20·7| --
|17 |Paints used || | | | | | | |
| |in other || | | | | | | |
| |industries: || | | | | | | |
| |Cases || 329| 36| 108| 21| 40| 13| 110| 12
| |Per cent. || 81·2|85·7| 26·7|50·0| 9·9|31·0| 27·2|28·6
|18 |Other || | | | | | | |
| |industries: || | | | | | | |
| |Cases || 428| 91| 161| 42| 58| 18| 121| 15
| |Per cent. || 81·1|79·8| 30·5|36·8|11·0|15·8| 22·9|13·2
| |Total cases ||4,512| 779|1,473| 325| 539| 255|1,190| 153
| | „ per || | | | | | | |
| |cent. || 80·0|77·8| 26·1|32·5| 9·6|25·5| 21·1|15·3
+-----+--------------++-----+----+-----+----+----+----+-----+----
+-----+--------------++-----------------------------+
| | || |
+-----+--------------++----------+---------+--------+
| | ||Encephalo-| Rheumat-| |
| No. | Occupation. || pathic. | ic. | Other. |
+-----+--------------++----------+---------+--------+
| (1) | (2) || (14) | (15) | (16) |
+-----+--------------++----+-----+----+----+----+---+
| | || M.| F. | M. | F. | M. | F.|
| 1 |Smelting of || | | | | | |
| |metals: || | | | | | |
| |Cases || 9| -- | 66| -- | 11|-- |
| |Per cent. || 2·2| -- |16·1| -- | 2·7|-- |
| 2 |Brass works: || | | | | | |
| |Cases || -- | -- | 9| 1| 3|-- |
| |Per cent. || -- | -- |12·9| -- | 4·3|-- |
| 3 |Sheet lead || | | | | | |
| |and lead || | | | | | |
| |piping: || | | | | | |
| |Cases || 2| -- | 11| 1| 1| 1|
| |Per cent. || 2·0| -- |10·8| -- | 1·0|-- |
| 4 |Plumbing and || | | | | | |
| |soldering: || | | | | | |
| |Cases || 10| -- | 21| 4| 8|-- |
| |Per cent. || 5·4| -- |11·3|13·3| 4·3|-- |
| 5 |Printing: || | | | | | |
| |Cases || 8| -- | 18| -- | 8|-- |
| |Per cent. || 4·2| -- | 9·5| -- | 4·2|-- |
| 6 |File-cutting: || | | | | | |
| |Cases || 7| -- | 16| -- | 20| 3|
| |Per cent. || 4·0| -- | 9·2| -- |11·5|8·8|
| 7 |Tinning and || | | | | | |
| |enamelling of || | | | | | |
| |hollow-ware: || | | | | | |
| |Cases || 4| 2 | 8| 4| 1|-- |
| |Per cent. || 4·8| 3·8 | 9·5| 7·5| 1·2|-- |
| 8 |White lead: || | | | | | |
| |Cases || 59| 6 | 98| 7| 14| 2|
| |Per cent. || 5·1| 7·9 | 8·4| 9·2| 1·2|2·6|
| 9 |Red lead: || | | | | | |
| |Cases || 9| -- | 13| -- | 3|-- |
| |Per cent. || 8·3| -- |12·0| -- | 2·8|-- |
|10 |China and || | | | | | |
| |earthenware: || | | | | | |
| |Cases || 26| 43 | 52| 67| 39| 8|
| |Per cent. || 5·3| 7·5 |10·6|11·7| 8·0|1·4|
|10_a_|Litho- || | | | | | |
| |transferers: || | | | | | |
| |Cases || -- | 2 | 5| 2| -- | 1|
| |Per cent. || -- | 7·1 |25·0| 7·1| -- |3·6|
|11 |Glass cutting || | | | | | |
| |and polishing:|| | | | | | |
| |Cases || 2| -- | 4| -- | 9|-- |
| |Per cent. || 4·2| -- | 8·5| -- |19·1|-- |
|12 |Enamelling of || | | | | | |
| |iron plates: || | | | | | |
| |Cases || -- | 1 | 6| 1| -- |-- |
| |Per cent. || -- | 7·1 |15·8| 7·1| -- |-- |
|13 |Electric || | | | | | |
| |accumulators: || | | | | | |
| |Cases || 5| -- | 12| -- | 2|-- |
| |Per cent. || 1·8| -- | 4·3| -- | 0·7|-- |
|14 |Paint and || | | | | | |
| |colour works: || | | | | | |
| |Cases || 8| 1 | 43| 2| 7|-- |
| |Per cent. || 2·0| 4·8 |10·8| 9·5| 1·8|-- |
|15 |Coach-making: || | | | | | |
| |Cases || 16| -- | 79| -- | 23|-- |
| |Per cent. || 2·4| -- |11·7| -- | 3·4|-- |
|16 |Ship-building:|| | | | | | |
| |Cases || 8| -- | 23| -- | 4|-- |
| |Per cent. || 3·1| -- | 8·8| -- | 1·5|-- |
|17 |Paints used || | | | | | |
| |in other || | | | | | |
| |industries: || | | | | | |
| |Cases || 10| 1 | 41| 3| 8| 1|
| |Per cent. || 2·5| 2·4 |10·1| 7·1| 2·0|2·4|
|18 |Other || | | | | | |
| |industries: || | | | | | |
| |Cases || 17| 6 | 43| 15| 15|-- |
| |Per cent. || 3·2| 5·3 | 8·1|13·2| 2·8|-- |
| |Total cases || 200| 62 | 568| 107| 176| 16|
| | „ per || | | | | | |
| |cent. || 3·5| 6·2 |10·3|10·7| 3·1|1·6|
+-----+--------------++----+-----+----+----+----+---+
To reduce the size of the table, columns showing the number in each
occupation in which (_a_) the severity of attack, and (_b_) the
number of attack were not stated, have been omitted. Of the former
there were 170, and of the latter 245. The total figures, however, in
Column 3 include them.
Table IV. shows the severity of the attacks as stated by the surgeon,
the number of attack, and the main symptoms. The personal element
enters into the character of the reports, and symptoms which one
surgeon might describe as slight another might regard as moderate,
or even severe. In general, however, “slight” includes cases of (1)
colic without complication, and of comparatively short duration;
(2) anæmia in adolescence aggravated by employment; and (3) either
of the above with tendency to weakness of the extensors. “Moderate”
includes (1) a combination of colic with anæmia; (2) profound anæmia;
(3) partial paralysis; and (4) cases in which there is constitutional
debility. “Severe” includes (1) marked paralysis; (2) encephalopathic
conditions--convulsions, optic neuritis, and mental affections; (3)
grave undermining of the constitution associated with paralysis,
renal disease, and arterio-sclerosis. The reports are made during
the attack, and information is not received of the sequelæ which may
supervene, except in the event of a later report as the result of
fresh exposure to lead. Number of attack has reference to definite
occurrence of disability. Transient attacks which have preceded the
disabling condition have been usually disregarded. It was necessary
to limit the number of attacks which might be regarded as indicating
chronic plumbism, and all those included in Column 10 are either
third attacks or cases of chronic lead poisoning. Among the main
symptoms, the headings “Gastric,” “Paretic,” “Encephalopathic,” and
“Rheumatic or Arthralgic,” represent fairly accurately the relative
incidence of these in cases of lead poisoning in this country; those
under the headings “Anæmia” and “Headache” are useful in comparing
relative incidence on the two sexes, but they occur, probably, much
more frequently than the figures would indicate; those under “Tremor”
and “Other” are less valuable. Under “Other” are included “Gout,”
“Nephritis,” or “Cerebral Hæmorrhage,” so that entry under this head
indicates chronic, rather than mild, lead poisoning. The conclusions
from the table are easy to draw, as, in general, the feature which
causes severity of symptoms to be prominent leaves its mark also on
“Number of Attack” and “Main Symptoms.” Thus, in the industries in
which severe cases exceed the average (brass, plumbing, printing,
file-cutting, tinning, glass-cutting, ship-building, paints used in
other industries, and other industries), the chronic nature of the
plumbism is markedly above the average, and some severe symptom,
usually paralysis, is also above the average. An exception to this
rule is china and earthenware, where severity is considerably below
the average, but where, among men, the figures for chronic lead
poisoning and paralysis are distinctly high. It will be seen, however,
that the proportion of slight cases even in this industry is below
the average. On the other hand, severity is below the average in
smelting, white lead, red lead, litho-transfers, enamelling, electric
accumulators, paints and colours, and coach-painting, and the symptoms
in these industries are, in general, colic rather than high degree of
paralysis; but in them a severe symptom which is above the average,
in general, is encephalopathy. The explanation of these differences
depends, we believe, on two factors: (1) Duration of employment, with
which, naturally, the age of the worker is associated; (2) opportunity
of inhaling lead dust. The longer the employment, the more likely,
naturally, if absorption goes on, is the plumbism to become chronic,
and to be associated with paralysis, its prominent sign. Duration of
employment among males in file-cutting and china and earthenware, as
contrasted, for instance, with that in white lead, is very much longer,
and the same could be shown of comparatively new industries, such as
electric accumulators and litho-transfers. Thus, in one year the age
distribution and duration of employment of those attacked in three of
these industries was as follows:
+---------------------+-------------------+-------------------+
| | | Duration of |
| | Age Distribution. | Employment. |
| Industry. +---------+---------+---------+---------+
| | | | Under | Over |
| |Under 30.| Over 30.| 5 Years.| 5 Years.|
+---------------------+---------+---------+---------+---------+
| |Per Cent.|Per Cent.|Per Cent.|Per Cent.|
|China and earthenware| 59·4 | 40·6 | 52·2 | 47·8 |
|White lead | 45·7 | 54·3 | 86·8 | 13·2 |
|File-cutting | 22·9 | 77·1 | -- | 100·0 |
+---------------------+---------+---------+---------+---------+
Persons employed in the manufacture of white and red lead, electric
accumulators, paints and colours, and the others named, are exposed
essentially to dust from salts of lead, which are readily absorbed.
Poisoning, therefore, if precautions are inadequate, will quickly show
itself, causing certain workers to seek other employment after one
attack. Poisoning thus produced is more likely to induce colic, or,
if the dose has been large or the individual markedly susceptible,
encephalopathic symptoms, than paralysis. On the other hand, the
slowness of the onset of symptoms in the case of brass workers,
plumbers, printers, file-cutters, and tinners, is more the result
of inhalation of fumes or of dust of metallic lead than of salts of
lead; or if the inhalation be of salts of lead, then of these in less
amount and over a long period, with, as a result, gradual undermining
of the constitution, showing itself in paralysis, arterio-sclerosis,
and renal disease. The two factors indicated obviously account for
the differences in severity and number of attack between males and
females. If second and third attacks are comparatively fewer in
females than in males, it follows that, in general, the attack will
be less severe also, and this is brought out in the figures. Cerebral
symptoms--encephalopathy, to which headache may be added--are more than
twice as frequent in females as males. This may be due to idiosyncrasy,
but it may very possibly be simply the result of short duration of
employment of young workers in processes where dust of salts of lead is
incidental.
Attacks generally are most frequent in the first or second year of
employment. Thus, of 2,195 attacks reported in the four years 1904
to 1907, as to which sufficient data are given, 898 occurred in the
first two years of employment, and of these 672 occurred in the first
year--that is, three-sevenths of all the cases were reported during
the first two years, and four-sevenths in the whole of the remaining
years of employment. It is, unfortunately, impossible to say what
is the proportion of attacks among those employed for any given age
period. In some factories--as, for example, lead smelting works--the
average duration of employment is about thirteen years. The length
of employment preceding an attack was made out from reports on cases
which occurred in the white lead industry in 1898--a time when a number
of new workers were taken on to replace the female labour abolished
in June of that year, and conditions as regards removal of dust were
entirely different from what they are now. The figures, therefore, can
only be considered to have bearing upon incidence under almost the
worst possible circumstances. Of 155 attacks, duration of employment
was stated to have been less than 1 week in 3, from 1 week to 1 month
in 8, from 1 to 3 months in 62, from 3 to 6 months in 44, from 6 to 12
months in 12, and 1 year and over in 26.
Attempt has been made to discredit the value of Section 73 of the
Factory Act, 1901, on the ground that the proportion of cases in which
some degree of paralysis is present is very high as compared with the
extent found by other observers. The points we have laid stress on--(1)
duration of employment, (2) varying kinds and amounts of lead dust and
fumes--are, we believe, quite sufficient to account for, and give value
to, the figures dealt with. To them should be added another factor,
though one of less account--namely, the extent to which particular
muscles are used. In the case of file-cutters, for instance, there is
no doubt that the cramped position of the left hand holding the chisel,
and the work thrown on the right in holding the heavy mallet, determine
the direction of the paralysis, especially on to the muscles of the
thenar and hyperthenar eminences and of the fingers.
There is, however, difficulty in deciding whether such entries on
reports as “weakness of arms and legs,” “weakness of arms,” “muscular
weakness,” etc., should be interpreted as incipient paralysis.[A]
With a disease like lead poisoning showing marked tendency to affect
the muscles supplied by the musculo-spiral and other nerves, the only
safe course was to include all these terms as equivalent to partial
paralysis. Table V. on p. 54 shows close parallelism for the six years.
[A] During the years 1910 and 1911 cases were classified so as to
distinguish definite paralysis, as far as possible, from the more
indefinite terms referred to, with the result tabulated opposite. We
have little doubt that in most of the cases included in columns (3)
and (6) some slight degree of paresis was present.
+--------------------+-----------------------+-----------------------+
| | 1910. | 1911. |
| +------+---------+------+------+---------+------+
| | | Weakness| | | Weakness| |
| | | of Arms | | | of Arms | |
| |Paral-| or Loss | |Paral-| or Loss | |
| Form of Paralysis. | ysis.|of Power.|Total.| ysis.|of Power.|Total.|
+--------------------+------+---------+------+------+---------+------+
| (1) | (2) | (3) | (4) | (5) | (6) | (7) |
|Arms and {complete| -- | -- | -- | 2 | -- | 2 |
|legs {partial | 4 | 6 | 10 | 1 | 4 | 5 |
| | | | | | | |
|Legs {complete| -- | -- | -- | -- | -- | -- |
| {partial | 4 | 4 | 8 | -- | 6 | 6 |
| | | | | | | |
|Both {complete| 15 | -- | 15 | 27 | -- | 27 |
|forearms {partial | 19 | 30 | 49 | 20 | 44 | 64 |
| | | | | | | |
|Right {complete| 8 | -- | 8 | 5 | -- | 5 |
|forearm {partial | 6 | 4 | 10 | 4 | 7 | 11 |
| | | | | | | |
|Left {complete| 3 | -- | 3 | 2 | -- | 2 |
|forearm {partial | 2 | 1 | 3 | 1 | 7 | 8 |
| | | | | | | |
|Fingers | 3 | -- | 3 | 7 | -- | 7 |
| | | | | | | |
|Neuritis (including | | | | | | |
|numbness of hands or| | | | | | |
|arms) | 5 | -- | 5 | 5 | -- | 5 |
| | | | | | | |
|Other (including | | | | | | |
|paralysis of | | | | | | |
|deltoid, muscles of | | | | | | |
|speech, locomotor | | | | | | |
|ataxy, and general | | | | | | |
|paralysis) | 1 | -- | 1 | 4 | 2 | 6 |
| +------+---------+------+------+---------+------+
| | 70 | 45 | 115 | 78 | 70 | 148 |
+--------------------+------+---------+------+------+---------+------+
If it is difficult to distinguish rightly all the cases classed as
“paralysis,” it is even more difficult to determine what should be
included under the term “encephalopathy.” We have limited it to
epileptiform seizures, optic neuritis (uncomplicated by epilepsy), and
various forms of insanity. Table VI. on p. 54 is interesting as showing
how fairly constant the numbers are from one year to another.
Except in the one industry of earthenware and china, in which a return
of the number of persons employed according to process and kind of
ware has been made on three separate occasions, and in which the
reports of the certifying surgeons enable the cases of poisoning to be
classified in the same way, it is difficult to determine accurately
the attack rate of lead poisoning. Even in the earthenware and china
trade many things have to be borne in mind. The poisoning which occurs
is not distributed evenly over all the factories. Thus, among the 550
potteries, in the years 1904 to 1908, five potteries were responsible
for 75 cases, and 173 for the total number of cases (517), leaving 377
factories from which no cases were reported.
TABLE V.--FORMS OF PARALYSIS: 1904-1909.
+-------------------------+------+-----+-----+-----+-----+-----+-----+
| Form of Paralysis. |Total.|1909.|1908.|1907.|1906.|1905.|1904.|
+-------------------------+------+-----+-----+-----+-----+-----+-----+
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) |
|Arms and legs {complete| 12 | 2 | 2 | 1 | 2 | 1 | 4 |
| {partial | 62 | 13 | 7 | 9 | 13 | 9 | 11 |
| | | | | | | | |
|Legs {complete| 3 | -- | -- | 1 | -- | 1 | 1 |
| {partial | 25 | 5 | 7 | 1 | 3 | 5 | 4 |
| | | | | | | | |
|Both forearms {complete| 162 | 29 | 33 | 29 | 28 | 24 | 19 |
| {partial | 334 | 59 | 70 | 56 | 56 | 43 | 50 |
| | | | | | | | |
|Right forearm {complete| 39 | 11 | 6 | 7 | 4 | 8 | 3 |
| {partial | 62 | 9 | 17 | 14 | 11 | 5 | 6 |
| | | | | | | | |
|Left forearm {complete| 14 | 2 | 2 | 4 | 1 | 3 | 2 |
| {partial | 22 | 4 | 1 | 4 | 6 | 4 | 3 |
| | | | | | | | |
|Fingers | 36 | 3 | 3 | 7 | 10 | 6 | 7 |
| | | | | | | | |
|Neuritis (including | | | | | | | |
|numbness of hands or | | | | | | | |
|arms) | 32 | 7 | 8 | 3 | 3 | 5 | 6 |
| | | | | | | | |
|Other (including | | | | | | | |
|paralysis of deltoid, | | | | | | | |
|muscles of speech, | | | | | | | |
|locomotor ataxy) | 10 | 3 | 1 | 3 | 1 | -- | 2 |
+-------------------------+------+-----+-----+-----+-----+-----+-----+
| | 798 | 147 | 157 | 139 | 138 | 114 | 118 |
+-------------------------+------+-----+-----+-----+-----+-----+-----+
TABLE VI.--ENCEPHALOPATHY.
+--------------+-----+-----+-----+-----+-----+-----+-----+-----+
| Symptom. |1911.|1910.|1909.|1908.|1907.|1906.|1905.|1904.|
+--------------+-----+-----+-----+-----+-----+-----+-----+-----+
|Epilepsy | 6 | 16 | 12 | 15 | 14 | 11 | 12 | 15 |
|Optic neuritis| 2 | 3 | 3 | 2 | 3 | 7 | 5 | 4 |
|Mental defect | 5 | 2 | 2 | 1 | 6 | 3 | 1 | 2 |
+--------------+-----+-----+-----+-----+-----+-----+-----+-----+
| Total | 13 | 21 | 17 | 18 | 23 | 21 | 18 | 21 |
+--------------+-----+-----+-----+-----+-----+-----+-----+-----+
The same state of things is found in all the other industries.
Particular factories, owing to special method of manufacture or special
manner of working, may have an incidence out of all proportion to that
prevailing in the trade generally. And it is, of course, control of
these more obvious sources of danger by the efforts of manufacturers
and the factory inspectors that has led to the notable reduction
recorded--_e.g._, in white lead works and the pottery industry.
Returns of occupiers do not lend themselves readily to exact estimate
of the number of persons exposed to risk of lead poisoning, as they do
not differentiate the processes, and in nearly all factories in which
lead is used some of those returned will not come into contact with it.
In industries, however, in which there is periodic medical examination
of persons employed in lead processes an attack rate can be made out.
It must be regarded as approximate only, as in the manufacture of
electric accumulators, for instance, medical examination is limited
to persons employed in pasting, casting, lead-burning, or any work
involving contact with dry compounds of lead, whereas the reported
attacks include a few persons engaged in processes other than those
named.
TABLE VII.--ATTACK RATE FROM LEAD POISONING IN THE YEAR 1910 IN CERTAIN
INDUSTRIES.
+---------------------+-------------+----------+---------+-----------+
| | | Probable | | |
| | | Number of|Number of|Attack Rate|
| | Number of | Persons | Reported| per |
| Industry. |Examinations.| employed.| Cases. | Thousand. |
+---------------------+-------------+----------+---------+-----------+
|White lead | 77,752 | 1,495 | 34 | 22 |
|Red lead | 8,096 | 675 | 10 | 15 |
|Vitreous enamelling | 3,064 | 766 | 17 | 22 |
|Tinning of metals | 1,475 | 492 | 17 | 34 |
|Electric accumulators| 13,065 | 1,089 | 31 | 28 |
|Paints and colours | 19,081 | 1,590 | 17 | 11 |
|Earthenware and china| 78,560 | 6,547 | 77 | 12 |
+---------------------+-------------+----------+---------+-----------+
As has been mentioned above, the accurate information we have of the
numbers employed in the several processes in the earthenware and china
industry enable us to use the figures for that industry to illustrate,
what is certainly true of all other lead industries also, the fact of
the relative greater degree of risk in one process than another.
The fall in the number of fatal cases attributed to lead poisoning, as
is perhaps to be expected, seeing that the great majority are deaths
from chronic lead poisoning, does not run parallel with the diminution
in the number of cases. Thus, in the five years 1905 to 1909 the
deaths numbered 144, as compared with 131 in the previous five years,
although the cases fell from 3,761 to 3,001. We believe this is due
to an increasing inclination to attribute chronic nephritis, and
even (without sufficient justification in our opinion) phthisis and
pneumonia, to lead poisoning on the death certificates of lead workers.
Copies of all death certificates on which lead poisoning is entered
as directly or indirectly a cause are received by the Chief Inspector
of Factories. All of industrial origin are included in the return. Of
a total of 264 which could be followed up, encephalopathic symptoms
appeared on the death certificate in 38 (10·6 per cent.); Bright’s
disease, cerebral hæmorrhage, paralysis, or chronic lead poisoning
either alone or as a combination of symptoms closely connected, in 188
(71·2 per cent.); phthisis in 13 (5·0 per cent.); and other diseases,
such as pneumonia, etc., in 25 (9·4 per cent.). Table IX. brings out
the relative frequency in the several groups of industries, and, as is
to be anticipated, the different average age at death when due to acute
and chronic lead poisoning.
TABLE VIII.--LEAD POISONING IN EARTHENWARE AND CHINA WORKS
(CHINA, EARTHENWARE, TILES, MAJOLICA, JET AND ROCKINGHAM, CHINA
FURNITURE AND ELECTRICAL FITTINGS, SANITARY WARE).
+-------------------------+------+-----------------+-----------------+
| | | | Attack-Rate per |
| | Per- | Cases Reported: | Thousand |
| | sons | Average | employed: |
| Processes. | em- | per Year. |Average per Year.|
| |ployed+-----+-----+-----+-----+-----+-----+
| | in |1907-|1903-|1899-|1907-|1903-|1899-|
| | 1907.|1910.|1906.|1902.|1910.|1906.|1902.|
| | | | | | [A] | [B] | [C] |
+-------------------------+------+-----+-----+-----+-----+-----+-----+
|In dipping-house: | | | | | | | |
|Dippers {M.| 786| 17| 18| 26| 22| 23| 34|
| {F.| 150| 6| 4| 7| 40| 30| 68|
| | | | | | | | |
|Dippers’ assistants {M.| 463| 3| 3| 7| 7| 7| 15|
| {F.| 397| 13| 18| 17| 33| 46| 45|
| | | | | | | | |
|Ware-cleaners {M.| 115| 1| 2| 3| 9| 20| 30|
| {F.| 461| 15| 18| 30| 33| 41| 65|
+-------------------------+------+-----+-----+-----+-----+-----+-----+
|Total {M.| 1,346| 21| 23| 36| 15| 17| 27|
| {F.| 1,008| 34| 40| 54| 34| 42| 58|
+-------------------------+------+-----+-----+-----+-----+-----+-----+
|Glost-placers {M.| 2,291| 16| 12| 33| 7| 5| 14|
| {F.| 120| 1| 1| 1| 8| 10| 14|
| | | | | | | | |
|Majolica-painters {M.| 28| --| --| --| --| --| --|
| {F.| 358| 6| 8| 10| 13| 14| 20|
| | | | | | | | |
|Ground-layers {M.| 58| 1| --| 1| 17| --| 17|
| {F.| 157| 1| 1| 4| 6| 5| 13|
| | | | | | | | |
|Colour and litho {M.| 14| --| --| --| --| --| --|
|dusters {F.| 143| --| 1| 4| --| 7| 33|
| | | | | | | | |
|Enamel colour and {M.| 51| --| --| 1| --| --| 36|
|glaze blowers {F.| 288| 3| 3| 2| 10| 14| 12|
| | | | | | | | |
|Colour-makers and }M.| 371| 5| 5| 6| 13| 13| 17|
|millers and mixers of }F.| 55| 1| 1| 1| 18| 48| 114|
|glaze or colour | | | | | | | |
| | | | | | | | |
|Other persons in }M.| 327| 2| 1| 2| 6| 5| 11|
|contact with lead }F.| 132| 1| 2| 4| 8| 21| 75|
+-------------------------+------+-----+-----+-----+-----+-----+-----+
| {M. | 4,504| 44| 41| 80| 10| 9| 19|
|Grand total {F. | 2,361| 45| 57| 80| 19| 25| 37|
| { +------+-----+-----+-----+-----+-----+-----+
| {(M. and F.)| 6,865| 89| 98| 160| 13| 15| 25|
+-------------------------+------+-----+-----+-----+-----+-----+-----+
[A] Calculated on return of employment for 1907.
[B] Calculated on return of employment for 1904.
[C] Calculated on return of employment for 1900.
The statistical evidence from death certificates published in the
decennial supplements of the Superintendent of Statistics[2] is of
significance, not only in enabling comparison to be made between one
industry and another, in regard to mortality from lead poisoning, but
also in determining the other causes of death most frequently entered
on death certificates of lead workers, and therefore, if they are
in high excess, as compared with male workers generally, they are
to be ascribed with some degree of certainty to deleterious effects
of lead on some of the principal organs. Thus, in Table X. a list
of occupations is given in which the mortality from plumbism in the
years 1900 to 1902 was double or more than double the standard. It
represents the mortality which would occur if the male population in
the particular industry had exactly the same age population as that of
“all males.” Further, the annual mortality among “all males” is taken
as 1,000, and that of males engaged in the several industries is stated
as a proportion of this. This “mortality figure” of 1,000 is made up
of the mortality from various causes (of which only those considered
to bear upon lead poisoning are given in the table) in the proportion
stated.
The contention that, because lead workers die from certain diseases
more frequently than “all males,” such diseases must be the sequelæ
of lead poisoning is untenable unless other recognized causes of the
diseases in question have been excluded. For excess of deaths from
phthisis and respiratory diseases the conditions of work and exposure
to inhalation of mineral and metallic dust or vitiation of atmosphere,
in pottery, spelter, printing works, and file-cutting workshops,
sufficiently account. The figures, indeed, take no account of this, and
their value, in some at any rate, is still further diminished by the
very large number of occupations (several involving no contact at all
with lead) included in the headings. With exception of the strikingly
greater proportion of deaths among lead-workers from Bright’s disease,
the figures are too contradictory to draw deductions from as to what
are “sequelæ” of lead poisoning. But this figure--160, as compared
with 35 for all males--is confirmatory evidence, if any were needed,
that chronic Bright’s disease is a sequela. And, from the pathology of
lead poisoning, we believe that the granular condition of the kidney
is due to the sclerotic change brought about in its substance by
microscopic hæmorrhages. We have very little evidence indeed in man
that this interstitial change is set up or preceded by an acute tubal
nephritis. While we do not deny that there may be some parenchymatous
change associated with lead poisoning, we do not believe that it
is of the kind which gives rise to the large white kidney, and we
should therefore exclude such disease as a sequela. But if chronic
Bright’s disease is admitted, the train of symptoms associated with
it--notably arterio-sclerotic changes resulting in cerebral hæmorrhage
and albuminuric retinitis--must be admitted also. Unless it were
established that granular nephritis were present in a lead-worker
before commencement of lead employment, we think it would be useless to
endeavour to prove that the condition was independent of lead, despite
its comparative frequency as a cause of death apart from employment.
TABLE IX.--MAIN SYMPTOMS APPEARING AS THE CAUSE IN 264 DEATH
CERTIFICATES OF LEAD POISONING.
+-------------------------------+--------+--------+------+------+
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| Industry. | | | Cere-| |
| | | | bral | |
| |Encepha-|Bright’s|Hæmor-|Paral-|
| |lopathy.|Disease.|rhage.| ysis.|
+-------------------------------+--------+--------+------+------+
| (1) | (2) | (3) | (4) | (5) |
|Smelting of metals | 1 | 6 | -- | 3 |
|Brass works | -- | 3 | -- | 1 |
|Sheet lead and lead piping | -- | 1 | -- | -- |
|Plumbing and soldering | 2 | 3 | -- | 1 |
|Printing | 3 | 3 | -- | 2 |
|File-cutting | 1 | 11 | 2 | 2 |
|Tinning and enamelling | -- | 1 | -- | -- |
|White lead | 13 | 2 | 2 | 4 |
|China and earthenware | 8 | 24 | 14 | 3 |
|Glass-cutting | 1 | 6 | -- | -- |
|Electric accumulators | 2 | 1 | -- | 1 |
|Paints and colours | 4 | 1 | -- | -- |
|Coach-making | 1 | 8 | 5 | 6 |
|Ship-building | 1 | 4 | 1 | -- |
|Paints used in other industries| -- | 3 | 1 | 4 |
|Other industries | 1 | 2 | 1 | -- |
+-------------------------------+--------+--------+------+------+
| Total | 38 | 79 | 26 | 27 |
+-------------------------------+--------+--------+------+------+
| Average at death | 32 | 43 | 47 | 43 |
+-------------------------------+--------+--------+------+------+
+-------------------------------+----+------+---------+------+
| | | | Pneu- | |
| | | | monia, | |
| | | | Bron- | |
| | | | chitis, | |
| | | | Heart | |
| | | | Failure,| |
| Industry. |Lead| | Colic, | |
| |Poi-| | Hernia,| |
| |son-|Phthi-| and | |
| |ing.| sis. |Aneurism.|Total.|
+-------------------------------+----+------+---------+------+
| (1) | (6)| (7) | (8) | (9) |
|Smelting of metals | 5 | 1 | 1 | 17 |
|Brass works | 1 | -- | 1 | 6 |
|Sheet lead and lead piping | 1 | -- | 1 | 3 |
|Plumbing and soldering | 2 | 1 | 2 | 11 |
|Printing | 5 | 1 | 3 | 17 |
|File-cutting | 2 | 1 | -- | 19 |
|Tinning and enamelling | 1 | -- | -- | 2 |
|White lead | 2 | 1 | 3 | 27 |
|China and earthenware | 6 | 2 | -- | 57 |
|Glass-cutting | 1 | -- | 1 | 9 |
|Electric accumulators | -- | -- | 2 | 6 |
|Paints and colours | 2 | 1 | 3 | 11 |
|Coach-making | 10 | 3 | 4 | 37 |
|Ship-building | 1 | 1 | -- | 8 |
|Paints used in other industries| 6 | 1 | 2 | 17 |
|Other industries | 11 | -- | 2 | 17 |
+-------------------------------+----+------+---------+------+
| Total | 56 | 13 | 25 | 264 |
+-------------------------------+----+------+---------+------+
| Average at death | 44 | 38 | 40 | -- |
+-------------------------------+----+------+---------+------+
TABLE X.--COMPARATIVE MORTALITY FROM SPECIFIED CAUSES AMONG MALES
ENGAGED IN CERTAIN OCCUPATIONS: 1900-1902.
+-------------------+------------------------------------------------
| | Causes of Death.
| +-------+-------+-----+------+------+-----+-----+
| | | | | | | Dis-| Dis-|
| | | | | | Dis- |eases|eases|
| | | | | | eases| of | of |
| | | | | | of | the | the |
| | | | | | the | Cir-| Res-|
| | | | | | Ner- |cula-|pira-|
| | | | | | vous | tory| tory|
| | All | Alco- | |Phthi-| Sys- | Sys-| Sys-|
| Occupation. |Causes.|holism.|Gout.| sis. | tem. | tem.| tem.|
+-------------------+-------+-------+-----+------+------+-----+-----+
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) |
|All males | 1,000 | 16 | 2 | 186 | 105 | 145 | 174 |
|Printer | 994 | 8 | 3 | 300 | 111 | 125 | 131 |
|File-maker | 1,700 | 14 | -- | 387 | 225 | 198 | 325 |
|Copper-worker | 1,090 | 7 | 3 | 162 | 104 | 139 | 357 |
|Lead-worker | 1,408 | 38 | -- | 165 | 134 | 222 | 309 |
|Coach-maker | 824 | 4 | 4 | 129 | 113 | 129 | 150 |
|Earthenware | 1,493 | 8 | -- | 285 | 131 | 219 | 473 |
|Glass | 1,260 | 7 | 4 | 283 | 131 | 177 | 268 |
|Painter and plumber| 1,114 | 13 | 8 | 213 | 133 | 105 | 168 |
+-------------------+-------+-------+-----+------+------+-----+-----+
+-------------------+---------------------------------+
| | |
| +------+--------+-----+-----+-----+
| | | |Other| | |
| | | |Dis- | | |
| | Dis- | |eases| | |
| | eases| | of | | |
| |of the| | the | | |
| |Diges-| | Uri-| | |
| | tive | | nary| | |
| | Sys- |Bright’s| Sys-|Plum-|Acci-|
| Occupation. | tem. |Disease.| tem.|bism.|dent.|
+-------------------+------+--------+-----+-----+-----+
| (1) | (9) | (10) | (11)| (12)| (13)|
|All males | 57 | 35 | 17 | 1 | 59 |
|Printer | 55 | 42 | 15 | 2 | 21 |
|File-maker | 78 | 134 | 26 | 56 | 46 |
|Copper-worker | 45 | 24 | 21 | 3 | 51 |
|Lead-worker | 14 | 160 | -- | 102 | 52 |
|Coach-maker | 46 | 39 | 14 | 8 | 29 |
|Earthenware | 57 | 33 | 20 | 10 | 33 |
|Glass | 54 | 58 | 16 | 8 | 31 |
|Painter and plumber| 31 | 74 | 20 | 23 | 50 |
+-------------------+------+--------+-----+-----+-----+
Other conditions which might readily be admitted as sequelæ are
optic neuritis, following on an attack of encephalopathy. No general
statement can be made in regard to mental and nervous diseases, gout,
pernicious anæmia, as sequelæ, as each must be considered in relation
to the evidence adduced in the particular case, and after exclusion, in
the first two, of syphilis as a cause.
The distinction between causation and association has to be borne
in mind before admitting as sequelæ of lead poisoning diseases of
bacterial origin, such as phthisis or pneumonia, or any disease to
which the affected person may be thought to have been rendered more
prone by reason of lead employment. The contention that a person
may have been debilitated by lead poisoning is no proof that the
enfeeblement of the constitution was the cause either of the bacillus
gaining entrance into the lung or of the ultimate fatal issue from
the engrafted disease. Such assertion in every case must rest on
supposition. Evidence that lead employment predisposes to phthisis is
not necessarily made stronger, in our opinion, by existence during
life of clinical symptoms, or, in their absence, of detection of lead
in the tissues post mortem.
In classifying causes of death, the general rule should be to select,
from the several diseases mentioned in the certificate, the disease
of the longest duration. Exceptions to this rule are that definite
diseases ordinarily known as constitutional diseases should have
preference over the other diseases mentioned. After thirty-five years
of age, certificates of death from lead poisoning are almost always
filled in in association with other diseases which are the usual causes
which lead to mortality generally. But neither phthisis, nor pneumonia,
nor any acute disease of the heart or lungs, nor valvular disease of
the heart, nor, indeed, any acute febrile condition, can have direct
relation with--_i.e._, be a sequela of--lead poisoning.
REFERENCES.
[1] Annual Reports of the Chief Inspector of Factories since 1898,
especially for 1909, p. 19.
[2] Supplement to the Sixty-fifth Annual Report of the
Registrar-General on the Mortality in Certain Occupations in the
Three Years 1900, 1901, 1902, by Dr. John Tatham, pp. cxix-cxxii, Cd.
2619.