In 1917 American physician and research scientist Alice Hamilton and Charles H. Verrill published Hygiene of the Printing Trades. Bull. U.S. Bureau of Labor Statistics Whole Number 209. Industrial Accidents and Hygiene Series: No. 12. This was probably the earliest thoroughly documented, detailed statistical study of the hygiene and diseases of workers in the U.S. printing industry, as compared to available statistics on workers in other countries. The 118-page work was also one of the earliest extensively detailed and throughly documented studis of the topic in any language. The authors cited European studies on the health of workers in the printing trades. Lead colic among typesetters, smelters, and stereotypers were among the most serious problems.
By 1917 Linotype and Monotype were well established in industrial printing facilities and newspapers. While the machines speeded up typesetting, eliminated the type distribution issues, and probably alleviated some of the issues associated with manual labor, and reduced absorption of lead through the skin, Hamilton and Verrill analyzed health problems specifically resulting from the use of these machines, and may have been the first to do so. The plates in the report illustrated elaborate ventilation systems for removal of noxious fumes from Linotype machines.
In the introduction they wrote, p. 5: "The special dangers to be considered in the printing trades, especially in hand composition, linotype and montype casting, stereotyping, and electrotyping, are the exposure to lead and antimony dust and to possible fumes from molten lead; to various volatile poisons used in cleaning press rollers and old type; to irritating and toxic fumes from remelting ink-covered type metal, and to poisonous fumes from the gas burners under the various type-casting machines.
"The description which follows is based on visits to 130 establishments --in Boston (including Cambridge), New York (including Garden City, L. I.), Philadelphia, Baltimore, Washington, Chicago, and St. Louis. Thirty-four of these were newspaper offices, 84 were book and job publishing houses, and 12 did electrotyping only. Of the book and job printing offices, 56 were large, employing more than 12 workpeople in the departments under investigation, and 26 were small, employing less than 12. In 4 there were type foundry departments. The departments studied were the composing room, including linotype operating and monotype casting, the stereotype foundry, the electrotype foundry, the pressroom, and the department in which used type is remelted and cast, and, in some cases, lead dross refined. Other departments, such as the bindery, or those of the various processes of photo-engraving and lithography, were not included....
"In all countries the printer's trade has been considered an occupation unhealthful beyond the average, and this belief is borne out by statistics, which an abnormally high sickness rate and death rate for printers as compared with all occupied males.
"Examination of all available sources of information in the United States shows that in this country the printer's trade is productive of more illness than would be expected in an industry where wages are high, hours usually not long, and where there is no gross contamination of the air nor exposure to excessive heat or cold, no overexertion. American printers suffer far more from tuberculosis than do occupied males in general.
"Statistics compiled from the records of the International Typographical Union covering almost 12,000 deaths between in 1893 and 1915, show a decided lowering of the death rate from tubercuclosis and an increase in the expectation of life. This improvement is greater than that among men in the general population during these years. It is probably to be attributed to improvements in shop hygiene, less exposure to lead owing to the use of machines, the educational work of the International typographical Union in regard to tuberculosis, the prompt care of tubercuclous printers since the establishment of the Printers' Home in Colorado, and the shorter workday. It is probable that the gradual rise in the standard of living among printers has also tended to lower the death rate from tuberculosis.
"The unhealthful features of the industry are the following: It is an indoor occupation, often carried on in vitiated air; it requires little physical exertion, and in consequence the printer's circulation is apt to be sluggish and he is oversensitive to cold; the nervous strain is great; the printer is exposed to the effect of various poisonous substances, the most important of which is lead.
"The importance of lead in the production of disease among printers is emphasized especially by the Austrian, Dutch, and Italian authorities, while the Germans are more divided on the subject, and the British believe that danger from lead is not great.
"Lead poisoning may be acquired by handling food or tobacco with hands which have become smeared with lead. It may also be acquired by breathing lead dust and fumes.
"The sources of lead dust are: In the composing room, the dust from type cases; in the linotype room, the scraps of lead from the machine which fall on the floor and are ground up by the feet of passers-by and the dust from cleaning machine and plunger; in stereotyping and electrotyping, the scraps from trimmers and routers and saws, and dross from the kettles. In addition most shops melt and recast used type and scrap, and this is another source of lead dust.
"Analyses of dusts collected from various surfaces in Washington printing plants showed the presence of lead, small in amount, but important because even very small quantities of lead in the air breathed for many years may cause chronic lead poisoning."
"Lead poisoning may also be acquired by exposure to the fumes arising from molten lead. Analyses of the air surrounding molten lead at the temperatures usual in the various processes of printing show that the heat used is not great enough to cause lead to be given off from these pots so long as the molten metal is at rest, but when it is agitated by stirring, or by skimming off dross, or by ladling and pour, there is a contemation of the air by the discharge of the fine, light coating of oxide which always forms on the surface of molten lead.
"In stereotyping, elecrotyping, and remelting and casting type, the agitation of the metal is enough to cause lead contamination of the surrounding air.
"In linotype and monotype casting the motlen metal is little disturbed and there is no evidence of air contamination from this source. It is highly probable that the symptoms of ill health complained of by linotypists and montype casters re in reality due to the contamination of the air by carbon monoxide from the naked burners under the melting pots. There should always be exhuast ventilation over such burner or electric heating should be substituted from gas heating.
"A slowly developing form of lead poisoning may occur in linotypists as a result of the dust incident to the work as it is usually carried on.
"Lead poisoning, when it occurs in printers, is of a slow, chronic, insidious form, not easily recognized because not typical. The chief injury done by lead is probably to be found, not in the production of true plumbism, but in a lowering of the resistance to oher diseases, especially to certain infections, In this way is explained the high death rate from tuberculosis. Lead poisoning and tuberculosis go hand in hand in this trade, both being highest in the occupations with greatest exposure to lead and both falling as cleanliness and good ventilation increase...."