Document jB3pOMwoJeRob75dq860EyzzZ

INDUSTRIAL DUST Hygienic Significance, Measurement and Control BY PHILIP DRINKER, S.B., Ch.E. Prc/Mur of Inductrial Hyeitn*, Harvard School of Public Health ano THEODORE HATCH, B.S., S.M. Instructor in Industrial Sanitation. Harrartl School of Public Health and Harvard Graduate School of Engineering First Edition McGRAW-HILL BOOK COMPANY, Inc. SEW YORK AND LONDON 1936 CHAPTER II EFFECTS OF DUSTS AND FUMES UPON MAN Exposure to dusts can produce four distinct types of disability: (1) the pneumoconioses, such as silicosis and asbestosis, are caused only by dust inhalation; (2) toxic dusts like lead, man ganese, and cadmium can produce their effect as the result of RIGHT BRONCHUS TKACHBA LETT BRONCHUS { BRONCHIAL RAMUS' UPPtR LQBt ` TO UPPtR LOBB+'J\ Sum* UlBETj BISHT LUHS~- ^UFT~;\ tUHS '! BRONCHIAL '{ RAMUS TO t UPPtR 1081 /f 45 I (PAXTBRMlfZ&i i\ BROHCHIAl- RAMUS TO MtOOLl lBt miPOlB--c (r:js.` ; BBO*CMAt\ RA *f05 ro LOvtfR i LOBS IGNCP. LOBS ^LOWtR LOte Fie. 10.--Lunn. bronchi. nd trche. (After Soixxta and McMurrieh.) either breathing or swallowing dust; (3) metal-fume fever is a temporary malady resulting from inhaling certain metallic oxide fmno: and (4) the allergic reaction or protein poisoning, as typified by hay fewer, i> the direct result of breathing pollen and other organic Mibstauces. In all four cases dust inhalation may be the soic cause of disability; only in the case of toxic is there another mode of entrance. Respiration and Dust Inhalation. The lungs arc iionsymmetnea: bilateral structures encased in a rather elastic cavity, 20 the chest, am c through the tri c or lobes and tl per cent larger In the norm diameter and Ik cartilage which j the approximate 1 the bronchi and lead to the termii as result, of insp: blood and air tak< ceils and carbon c The amount of with the task pe rates at which an Table 1. TaJIX 1.----OXTCEtf Retting in bed Silting... Standing... . Walking 2 m.p Walking 4 m.p Slow run .. Maximum exei 1 AJur Htadaraon nd 1 Toe ordinary in per minute, the h such as long-distan The inspiratory' but practically we required for a coin pauses that occur i Thus with minute at the rate of 100 h 3S6410 asrrvrjr -- l II i FUMES UPON MAN urdi-tinct types of disability: silicosis and asbestosis, are 2) toxic dusts like lead, man* their effect as the result of LEFT SXOHCHUS ' StfOHCHtAL RAMUS' to upper lobe 'upper LOSE ,'CEfr f LUHS SROKHlALf ANUS'* TO LONER . LOSE i 'Z^HjOWER LOBE tAfirr SottoUa and McMvmcii.) t; (3) metal-fume fever is a .haling certain metallic oxide )n or protein poisoning, as : result of breathing pollen .11 four cases dust inhalation ; only in the case of toxic ucc. The lungs are nonsymi in a rather elastic cavity, EFFECTS OF DUSTS AND FUMES UPON MAN 21 the chest, and they communicate with the nose and mouth through the trachea or windpipe. The left lung has two divisions <>r lobes and the right lung has three; the right lung is about 12 ler cent larger than the left. In the normal adult, the trachea is a tube sonic I to 2 cm. in diameter and 10 cm. long t.Fig. 10); it is fortified wiili ringiike cartilage which give- it a .strung and inelastic character. At the approximate level of the fourth rib, the trachea branches into the bronchi and those in turn subdivide into bronchioles which lead to the terminal air sacs or alveoli. It is in the alveoli that, as result of inspiration and expiration, gas exchange between blood and air takes place. Oxygen is taken up by the red blood ceils and carbon dioxide is given off. The amount of air breathed and the oxygen consumed vary with the task performed and with the individual's size. The rates at which an athletic man of 150 lb. breathes are shown in Table 1. Tsut.r. 1 --Oxvr.c.v < (ivscmctios- a.vd Vocent or Breatiiis-c t Mas1 Oxygen consumed t 0*C. And TOO Air lirc.itlied mm. pressure, liter* per minute at20*C., liters per minute Resting in bed Sitting Standing . ... Walking 2 m.p.li Walking 4 m,p.h Slow run.. Maximum exertion I 0.24 0 30 0 30 0 65 1.20 2.00 3 00-4 00 G 7 8 14 2G 43 G5-100 Afut Htndcnon and IUcard (124). The ordinary individual seldom breathes more than 50 liters per minute, the high rates being limited to trained athletes, such as long-distance runners. The inspiratory and expiratory phases are not exactly alike, but practically we may `consider each as taking half the time required for a complete respiratory cycle and we can ignore the pauses that occur at the beginning and end of each inspiration. Thus with minute volume of 50 liters the actual inspiration is at the rate of 100 liter- per minute and momentarily rather high N firm n DCS' T"c:u conclusion regarding -ii- i- iiiti.ainco from a tingle .:.':i:i, Table 2Si. ;F SPb'TUM na.-.ii di.-charge of iK.-raon* :|,aee It lias always horn and i- sufficiently .-cu.-itivi' ' of :i inspirator (page 26S) charge, diluted if necessary, s by smearing on a slide and micr<>im:moration technique iiiarv examination indicates ential if a polarizing micro:- toclmiquc that the "siliaiveolar phagocyte of an lily In* demonstrated." ed when sampler of 100 cc. is healed in a beaker over tur Ii;ln been evaporated, are added and the mixture being shaken at intervals; for 1 hr. The residue is d incinerated, an accurate case history, tion of dusts in sputum, i hi-tory of recent dust suffices for identification ir dark, even black, before ,:ig i- caused by pigmenta'inovd by treatment with ..< such as the histologist tid'-d. '.rgc examinationsfordust, oi her preventive measr'r/-dom fromdustin both --to'/d by layman and medvot photographically and .ny person familiar with ha- been demonstrated. i ii i i i i I CHEMICAL AS'D MINEKaIjCXjICAL ANALYSIS 165 The dust in phagocytic cells from human sputum wa- studied by Drinker i03i, who was able to identify several mineral.- in the < ells and to establish figures of average particle size in phagocyte-. In order to examine du.-t m phagocytes, the sputum sample must lie fixed when fresh, and it is best to make several slides, some -tamed and some unstained. Stains interfere seriously with the mieru-eopy of the particles but help one to pick out the dust cells from extraneous matter. Aging of the sputum results in bacterial action ujhiii the cells which destroys their outline, and must !* avoided.1 The cells from silicotics (coal miners) which we have seen recently contained a great percentage of carbon and little else. Since there is little difficulty in getting such cells from patients with silicosis or with a history of recent dust exposure, more such examinations might easily and profitably be made. It should be borne in mind that the presence of dust cells in human sputum does not of itself prove any lung pathology. Thi.mav be a normal finding and often occurs in the healthy city dweller, particularly if he is a smoker. But in the ea-e of the individual with proved dust exposure, the presence of numermidust cells in sputum may help in diagnoses. THE IDENTIFICATION OF ASBESTOSIS BODIES m For the identification of the "curious" bodies (see Fig. 15. page 33) found in asbestos workers, Stewart (223) employ-- the following technique: About half an ounce of sputum is dissolved in an equal quantity of undiluted antiformin in a wide test tube. This takes from a few minuteto 3.n hour or so. ami is aided by heat (37*C. incubator) and gentle agnation. Two or three ounces of water are then added and the mixture allowed to stand for a few hours or overnight. The bulk of the suiiern&tant fluid is now poured off and the remaining 12 to 15 cc. centrifuged at moderate speed for 10 min. The amount of deposit which conntlown vanes in different specimens, but in any case the whole of the supernatant fluid may be poured off by simply inverting the centrifuge t.ibc. The deposit and the trace of fluid which remain are thoroughly 1 It is assumed that any person examining the dust particles in sputum or m nasal discharge will familiarize himself with the accepted routine of puitim examinations as curried out in ordinary medical diagnoses. He nec,| observe only the uicihoiU of preparing the specimens and uecd not lie rmiri riinl mill liaelermlogu'iil or palliulugiciil matt era. C C C o c a $ /t/c- fer-^ 396412 3 GO ixdi srniAL nr.'it mixed by menns of a fine pijx-tto mul transferred to an albuminized slide tir slide.1). Too much fnri-i- imw n--t !.- n.-ed m the mixing process or at any previous stage in order nut U> di.-inU-gratc any clumps of asbestos bodies winch may be present. As a rule the whole deposit' from half an ounce of sputum may lie spread over an area of 1 sq. in. of a microscope Midc. or less, and in any case a thick him is desirable. After thorough drying on a hot plate and final fixation over a Bunsen, the him is very gently washed in water, dried and mounted in Canada balsam. The washing in water must lie done with the greatest care, as, in spite of the albuininization of the slide, the film is very easily detached, especially if it ts thick. After washing and dryme. the film may be treated with ferrocyanidc of [Kitassium and hydrochloric aval to demonstrate the Prussian blue reaction given by the bodies, h i.- then dried and mounted in balsam as before. Alternatively the centrouged deposit may be covered with a small quantity of a 5 per cent solution of ammonium sulfide, when the bodies are colored black. No sjweial staining is required, however, as the natural greenish yellow. golden, or brown color of the bodies renders them sufficiently conspicuous even under the low power. My practice is to examine films with the t-in. objective and 10X ocular, confirming the presence of asbestos bodies with the i-in. objective. It is necessary to cleanse thoroughly all test tubes, centrifuge tubes, and pipettes aiter use: otherwise there is a risk of contamination of sub sequent specimens from a |x.-.nive .-putnm. Asbestos bodie* are ih-umii-t ruble by tins method in the great majority of asbestos workers provided they hate any exjicctoratiim. 'In the older workers, especially during a bronchitic attack and in the later stages of pulmonary a>besio-i. bodies are present in profusion, but. even tit those who hate only In-on engaged in the industry for a year nr two. they- may be demonstrable in `-mall numbers. Their presence indicates merely that asbestn.- dust has Ixjcn inhaled into the lung and that it has remained there long cnowm for '`bodies" to form around individual fibers, a period of months at least. It does not necessarily mean that there is pulmonary fibrosis. The finding of radially arranged dumps of Undies similar to tito-e demonstrable histologically within Un iting alveoli has much more mtiiiii-. .Mgiiiiicanee. It indicates disinte gration of "living ti-Mie. either by Mippuraiivv bronchopneumonia or by tuberculous cn-ealiim. mul may U- taken also as presumptive evidence of an underlying a-lie-iuM'. Bodies somewhat similar to tixhwUis botlie- but much coarser and more irregular have been recovered from the lung.-, of coat miners who Intel never worked m a-un-ti- The morphological difference-- art- so great, however, that there is ht.leor no risk of confusion. y i'/ fVfcCt *' tkieL CO a METHODS FOR Two steps are First, reduce the means of control to dust "action am means of suitable medical exaiuinnt problem of cnnroi tion of medical or balanced program Individuals v: of dust owing to weaknesses caused tuberculosis, etc. selected for fu in chest X-ray pu-ut inations thercafu resistance against Two purposes development of ii the victim can be ous source of infc prevent the dove continued dust e which lower the i in time to tran.Mipermanent dam: provides the uni; program, since in of lung damage program. An nu control or the ado > 396413 /