pubmed-article:809410 | pubmed:abstractText | To assess early ventilatory responses at the 2 mg/m3 bituminous coal dust standard, 23 cynomolgus monkeys were exposed by inhalation to Pennsylvania and Utah coal dust. Ten controls were utilized. Pennsylvania coal was selected from a field having a high prevalence of coal workers' pneumoconiosis while the Utah coal was selected from a low prevalence area. After 24 mo of exposure, a pattern of pulmonary impairment consistent with peripheral airway obstruction was demonstrated. Reductions were observed in the forced expiratory volume in 1 s, maximum midexpiratory flow rate, and especially maximum expiratory flow at small lung volumes. Hyperinflation (RV/TLC) was observed in both coal treatments; however, no specific lung volumes differed significantly from controls. No differences were found between the Pennsylvania and Utah treatments. Design and specifications for a new hydraulically operated plethysmograph-respirator are included. | lld:pubmed |