Document oeja87dv7q6BneK4GYJGomz9g

c& the preceding auction, pi..uced a fibrosis{ when the matorlel vas pro* pared by flrit grinding tho fibrous duet until tho length of flbera was roduoed to 2D mlorons and loos or, Ln oomo caaoa, to 3 itlorans and ^fos, none of tho ltij<teLod dusts caused fibrosis, lf These results litffor fra* those of Ring, t al/W o report tho production of rutlculosLs' comparable with tho experimental silicotic nod- ulo In rabblta i-ocoLving monthly Intratrsoheql injections of 100 mg. of Rhodesian asboslos flbors, IS olorons long, and the production of diffuse Interstitial fibrosis La rabbits similarly Injooted with short .fiber*, 2.3 microns ln length, flo believe this dose, eopeolslly In tho lonjgjjfcorm rabbits. Is highly oxcosslvo. In our experiments tho dosage was leapt low ln ardor to miniailxo untoward reactions vfolah might obsoure tho peribron chiolar type of fibrosis which characterises oorly human ssbestoai*. EXTEKiythTC usi;;c INTHAVEHOUS TECHNIQUE ^' The experiments, summarised In table 17, ln which the intravenous method of injoctlou \rafl omployed, char# that tho asbostos minerals are far dlfforent from quarts In their notion on tissue. It hao boon r epeatedly demonotratad thnt lntravonoua Injeotlon of quarts partlolee 3 mioroas and lose In diameter will cause a typical tissue reaction with the develop ment of hyallnlsed fibratio lesions In oxtra-pulnonary sites, such as tho liver and the splocn. Asboctoa rain orals, however, on Intravenous injec tion generally produce only n;i inort typo of reaction, as Is rovealfgl by -i .mm i u . -- in- i in --........ .ni.i.n (.Hi .................. 14 i 1<3, Xing, E.J., Clegg, J.H. and P.a^ V.V.i Effoct of Asbostos, and of - Asbestos and Aluminum, on Lunge of Rabbits, Thorax li 188 (Sept,) 194G, Abetr, in Indust. Bye, Digest \\t Ho, 23i (Fe*b,) 1917. \ -37- ho f T"