Bone Processing Industry

BONE PROCESSING INDUSTRY. The products of bone processing are bone fat, glue, bone charcoal, bone meal for fertilizer, and bone articles (buttons, toothbrushes, studs, piano keys). The extraction of phosphorus from bones, which was previously practiced on a large scale (e.g., the English factory in Oldbury near Birmingham and French factories in Lyon and Saint-Denis, which supplied phosphorus to almost the entire world, consuming 150,000 tons of bones annually; 4 factories in Russia, etc.), has now given way to the electrolytic extraction of phosphorus from phosphates (2 factories in Germany). Russian factories, where labor was poorly mechanized and carried out by semi-artisanal methods, were particularly unfavorable from a sanitary-hygienic standpoint. The last phosphorus factory in the USSR in Troitsk, Ural Oblast, was closed at the insistence of the labor inspection in 1926. The hazards of the bone processing industry are highly diverse depending on the individual production processes: 1. Storage and sorting of bones. When large quantities of bones are stored, they easily undergo decomposition; adhering soft tissue parts undergo putrefaction, and a stench spreads far around such warehouses. In the air of tightly closed rooms, the content of O₂ is greatly reduced, and CO₂ and NH₃ are present in large quantities, so that anyone entering risks suffocation. In USSR factories, bones are usually stored and sorted in an uncleaned state, in the open air or in completely unsuitable premises, as a result of which the stench spreads to a significant distance from the factory, especially in summer. Sorting of un-disinfected bones is usually done manually, and transportation is open (in bulk on trolleys, wheelbarrows), which is associated with the risk of infection of workers (anthrax, etc.). 2. Crushing and grinding of raw bone on crushing drums are associated with a large release of dust. 3. Degreasing of bones in the extraction department with steam under pressure or with hot gasoline vapors. The latter method eliminates the scorching of organic substances and the associated stench, and dirty wastewater characteristic of conventional methods is not formed. However, if the apparatus is not completely airtight and has other imperfections, gasoline vapors may enter the air. 4. Purification of extracted fat with strong mineral acids. In this process, pouring H₂SO₄, which is usually accompanied by a violent reaction and splashing, can cause burns. 5. Processing of extracted bones in the polishing department, where dust and the upper layer of the bone are knocked off by a drum. This releases particularly fine dust (at a factory in Pokrovsk in 1924, up to 1,200 mg of dust was found in 1 m³ of air; at a factory in Nizhnedneprovsk—1,666 mg). 6. Extraction of glue from polished and degreased bone by means of water vapor under pressure, diluting it with hot water, evaporation in vacuum apparatuses, and treatment of liquid glue in the sulfuration (gasification) department by passing sulfur dioxide vapors. Glue extraction can also be carried out with HCl. Boiling glue in open vessels, which is often found in small enterprises, is accompanied by a far-reaching stench. 7. Drying of glue in a drying room (up to 70°C). 8. Grinding of degreased and deglued bone into bone meal in a ball mill. 9. Processing of bone meal into superphosphates with sulfuric acid in the superphosphate department, accompanied by the release of sulfur dioxide, hydrofluoric acid, as well as phosphorus and arsenic compounds into the atmosphere of the workrooms (the latter are contained as impurities in ordinary H₂SO₄). In the superphosphate department of the Nizhnedneprovsk factory, traces of hydrofluoric acid were detected in the air. 10. Grinding, mixing, and sifting of superphosphate in the disintegrator department, accompanied by a large release of fine mineral dust. 11. Production of bone charcoal by roasting degreased bones in closed vessels at red heat without access of air. The qualitative and quantitative composition of the resulting distillation products depends on the method of conducting it: among the gaseous products are CO₂, NH₃, cyanide compounds, and combustible gases (coal gas, usually piped back into the furnace, thereby saving fuel). Liquid products condensed in coolers contain ammonium salts of carbamic and sulfuric acids, pyridine bases, fatty acid nitriles, and serve for the preparation of bone oil with a sharp, highly unpleasant odor. 12. Manufacture of bone articles by sawing, turning, and polishing bone is associated with the release of the finest bone dust. 13. Extraction of phosphorus from bone by treatment with sulfuric acid and roasting with coal powder (see Phosphorus). Thus, among the hazards associated with bone processing, the following should be particularly noted: 1. Dust emission. Bone dust, especially fine dust, causes irritation of the mucous membranes (bronchitis, tracheitis, blepharitis, conjunctivitis); punctures and injuries produce poorly healing suppurations and dermatitis. In France, a special "bone fever" (fièvre des os) has been noted; De Marraix described in 1907 among workers of a button factory "button-makers' bone disease" (maladie des boutonniers en os), manifested in inflammation of the fingers and affecting all workers without exception. Both diseases are apparently associated with the influence of bone dust and some special general action of it. During an examination of workers at a Leningrad factory in 1925 (232 people), respiratory organ damage was found in 26.3%; among workers of the Pokrovsk factory, respiratory diseases were found in 30% (278 people); among workers of the disintegrator department of the Nizhnedneprovsk factory, conjunctivitis, tracheitis, laryngitis, and bronchitis were found in the "vast majority." 2. Release of vapors and gases from decomposing bones and from various substances used. From an occupational hygiene point of view, the release of vapors of hot gasoline, hydrochloric acid, hydrofluoric acid, carbon dioxide, and sulfur dioxide should be especially taken into account. In Great Britain and France, cases of gasoline poisoning during bone degreasing were registered; at the factory in Nizhnedneprovsk, unloaders of degreased bones experienced dizziness and fainting spells, apparently under the influence of gasoline vapors in the air. 3. The influence of increased air humidity (evaporation department) and heat (drying room). 4. The danger of infection with anthrax and other infections (glanders, tuberculosis, tetanus). Cases of anthrax during bone processing have been registered in Great Britain (1914), Japan (1913), Germany (2 cases in 1924), etc. 5. The danger of traumatic injuries by sharp bone fragments (sorting, crusher). 6. The danger of burns (H₂SO₄, hot gasoline, etc.). Measures to eliminate hazards: establishing bone processing factories at a sufficient distance from residential areas; installing rational ventilation and cemented, impermeable, preferably sloping floors with drains in bone warehouses; frequent washing of them with chlorinated or formalin water; preliminary treatment of bones with chloride of lime or milk of lime; complete sealing of vessels and apparatuses in all distillation processes; disinfection of suspicious bones with heat (15 minutes at 100°C or 4 hours at 80°C); wetting bones to reduce dust; rational design of crushing drums, mills, and saws with local exhaust systems; providing workers with appropriate work clothes and, where necessary, supplying them with respirators. Legislation. By decree of the People's Commissariat of Labor (1929), work on bone crushers, polishing, mills and sifters, and in diffuser and evaporation departments was classified as hazardous occupations (entitling workers to additional leave and milk). At the request of local organs of the People's Commissariat of Labor, adolescents are not allowed to work; a 6-hour workday has been introduced in mills, for boilermakers of extractor and diffuser departments, in bone drying rooms, and in hauling (Leningrad). In Austria, Spain, France, Italy, and New Zealand, there are special instructions on the import of bones. Mandatory disinfection of raw bones has been introduced in Australia (with steam), in Canada, in the United States (with hot water at 74°C for 15 minutes), and in Spain (for raw bones from Morocco with sulfuric acid). In France, disinfection is only recommended; in Germany, degreasing is mandatory. In Holland, pulmonary diseases from sawing and grinding bones are registered as occupational diseases. In France, adolescents under 18 years of age are not allowed to work in dusty departments; in Japan, boys under 15 and women under 21; in Spain, boys under 16 and women under 21; in Belgium, adolescents under 16 are not allowed to work in sorting, gasoline extraction, and bone charcoal production; in Argentina, women are not allowed in bone charcoal production.

M. Shapiro-Aronshtam.

Industrial bone. A distinction is made between sausage bone, table bone, field bone, and grave bone. The procurement of sausage bone does not present any particular hazards from a sanitary point of view, provided that the processing plants receive the carcasses from slaughterhouses or other sources secured by veterinary-sanitary supervision. The same applies to table bone; although here the safety of origin is theoretically less guaranteed, in practice it is satisfactory, since the meat of animals infected with anthrax can reach kitchens only under completely exceptional conditions. Field bone is always suspicious from a sanitary standpoint, given that the vast majority of animals that died and were abandoned in the fields perished from anthrax; its collection and admission into industry is mostly only temporary (in case of a shortage of other types of bone) and conditional; in this case, it is required that the bone be light and completely white, on the (unproven) assumption that even the bone of anthrax carcasses loses its infectivity after prolonged natural weathering in the field and the direct action of sunlight. Grave bone, dug up in animal burial grounds or collected in fields but not yet having reached the aforementioned degree of lightness and whiteness, is absolutely excluded from industrial use; its procurement is associated with the direct danger of anthrax infection. Government regulations require: "the prohibition of procurement in areas declared unsafe due to infectious diseases" and "the suspension of procurement and export in areas in the event of an epizootic outbreak therein, pending clarification of the disease by the relevant district veterinary physician" (Circular of the People's Commissariat of Agriculture of the RSFSR and the People's Commissariat of Trade of the USSR dated May 18, 1926, No. 194/11-V, S). The storage of bone requires certain sanitary precautions, on the one hand due to air pollution, which inevitably occurs during the decomposition of soft tissues remaining on the bones, and on the other hand to prevent access by rats, mice, and flies. In domestic settings, it is sufficient to collect bones in dry, closed containers, provided they are not stored for long. At primary procurement bases, where the storage period must also be short, there should be relatively small, dry, closed rooms, separate for bones from known healthy animals and for bones of unknown origin or suspected of infection. In industrial warehouses, in addition to the isolation of rooms for bones of the two aforementioned categories, internal equipment meeting sanitary requirements is necessary: sufficient volume, ventilation, and impermeable walls and floors. Regarding the location of storage warehouses, there are the following regulations: warehouses "are prohibited from being established within the limits of cities, towns, and settlements, and are permitted only outside their boundaries, and no closer than 300 meters from residential buildings, away from the prevailing winds of populated areas, as well as the boundaries of the residential planning area, according to existing planning projects," "it is prohibited to build them along the banks and slopes of rivers and other water sources used for drinking purposes, and is permitted only away from places of recreation and leisure of the population (parks, groves, physical culture grounds, etc.), children's and medical-sanitary institutions, cattle-driving routes, and livestock grazing areas" (Instruction approved by the People's Commissariat of Agriculture, the People's Commissariat of Labor, the People's Commissariat of Health, and the People's Commissariat of Internal Affairs; announced by the People's Commissariat of Agriculture on December 24, 1927, No. 425/38-V, S). According to the same instruction, "it is prohibited to accept raw animal products at warehouses without the established veterinary certificates, and is permitted only in extreme cases, in the absence of veterinary supervision in the procurement areas (volosts, district councils), with certificates from village councils confirming the safety of the place of origin of the said products regarding infectious diseases." Transport. On highways and dirt roads, the transport of bones is permitted subject to the following sanitary rules: "before dispatch from the places of purchase to the destination, they must be presented for inspection to the relevant veterinary physician," who provides them with a certificate indicating "their sanitary safety and the safety of the places of origin and transit." Export from unsafe localities, from which "the export of raw materials is prohibited, may be permitted with the authorization of the relevant veterinary physician or veterinary executive commission, with the reasons for the authorization and transport conditions indicated in the issued certificate, and with a prohibition on removing part of the raw materials en route." "Bones are permitted for transport only in dried form and cleaned of soft parts"; in this case, they "must be packed in durable sacks, in barrels, or placed in carts and sledges lined with bast mats and tightly covered with bast mats or tarpaulins" (Rules approved by the People's Commissariat of Agriculture, the People's Commissariat of Railways, the People's Commissariat of Trade, the United State Political Administration, the People's Commissariat of Justice, and the People's Commissariat of Health; announced by order of the People's Commissariat of Agriculture dated December 28, 1927, No. 431). On railways, the following conditions must be observed when transporting bones: a) bones must be cleaned of external soft parts and dried; b) shipments of bones must be accompanied by certificates of veterinary supervision from the place of export. Bones "consigned abroad are subject to mandatory veterinary inspection at the station of departure." "Bones are permitted for transport in bulk." "In carload shipments of bones, they must be stored as far as possible separately from food and other goods" (Rules published by the People's Commissariat of Railways in the Collection of Tariffs, No. 403 of February 9 and No. 417 of May 18, 1927). All railway cars, after unloading raw animal products from them, must be cleaned and washed each time, and when necessary, disinfected. On waterways, the sanitary rules and conditions for the transport of bones coincide with those just mentioned for railways, with the only significant difference being that bones are permitted for transport on cargo-passenger vessels only in packaging (Rules published by the People's Commissariat of Railways in the appendix to the Collection of Tariffs, No. 398 of January 5, 1927).