Document Ozq847ppYaJ8K7zJxg4Bx9Ldv

- . _. ^ ours ;"p*cie3 of Ant~-.* character istic fclasu/* ehon^*? rtilch ar* slaflsr to tha lesions of huean aabaatotla. Siaca tha Life--aroan of tha rperi:-jrtt-il ar.is&i is relatively short, it is not possible to irrelr? the characteristic lesions in calml* radar the usual industrial con dition*. Con*t3aiCTUl7'; to obtain a coarnlats evaluation of tha tiaaua roapcose to inhaled particulate and fibrous notarial, it la rcessary to accelerate the reaction by t&plispj^ higher coccentrationa of duet than would ordinarily b o> counfcorsi in industry* TThiia condition* of exposure are thus different, tfw infera*t ion yielded by arperinante vrith snisai* la invalazbls in furnishing a better urxi aretending of the reaction of the huaaa organ* saa to inhaled aabaetoa dust* 5, Zxnariaental Mathoda 7or investigating the biological reaction of the experlaental arlaa.I to tbr various wbertoe xiaarala, tw? typo* of tachaiqus hare been eaployed, ruoaly, tha inhalation Bathed and the infection aothod. In inhalation expariaeote, group* of eninala - up to 100 or sore gutnaa pig* and eoaottiss* esallar sabers of rabbits, cats, dogs, rtxt or idea - are kept fer sight boors a day in. a cubical dnrt rocs, eight fe*t in dlaanaion, in vfcicn a cloud of asbestos dust is aairrtalned. , it istarrale during tba experiment, a few or.iaala or* aacri fined and tha tiaras xjwdBsd to dxtsrntas th* osture and extant of tha dost reaction* Sons anlnala sr* exposed for periods op to three rears, 7h* injection experiarata, in afalch th* duat; either dry or fuapeodai .ia fluidj, is introduead into the srdaal by tha intr*Toouar intraperitorsaal or intratradsoal procedure.- are used to dternine ehather or not a particular dust *. potential capacity to produce tiasua reaction,