Ventilatory function and personal breathing zone dust concentrations in Lancashire textile weavers

Background-To report findings on ventilatory function and estimations of co ncentrations of personal breathing zone dust in Lancashire textile weavers. Weaving room dust is considered to be less harmful than that encountered i n the cardroom or spinning room and weavers are generally thought to have l ess respiratory disability than carders or spinners. However, this occupati onal group has not been extensively studied. Methods-Each person was given a respiratory symptom questionnaire (modified Medical Research Council, UK, questionnaire on respiratory diseases). Vent ilatory function tests, forced expiratory volume in 1 second (FEV1) and for ced vital capacity (FVC) were performed on each person. A representative sa mple of workers from each occupational group underwent dust sampling in the ir personal breathing zone. Dust concentrations and ventilatory tests were analysed statistically with the Student's t test, Pearson's correlation coe fficient, and forward step regression for relations with symptoms and envir onmental factors. Significance was p greater than or equal to 0.05. Results-The FEV1 and FVC were reduced in workers with respiratory symptoms (non-specific chest tightness, shortness of breath, persistent cough, and w heezing) as well as in preparation room workers, current and former smokers , Asians, those working with predominantly cotton fibre (>50% cotton) and s tarch size. Mean total dust concentration (pdl) in the personal breathing z one was 1.98 mg/m(3). The corresponding value for total dust with large fib res lifted off the filter paper (pd2) was 1.55 mg/m(3). There was a strong correlation (r=0.94, p<0.0001) between pdl and pd2. Non-specific chest tigh tness was predicted by low dust concentrations and persistent cough by high dust concentrations. On regression analysis, impairment of ventilatory fun ction (FEV1, FVC) was predicted by smoking, male sex, age, not working in t he weaving shed, not being white, and personal dust concentrations. Conclusions-The FEV1 and FVC were impaired in smokers and those exposed to high dust concentrations in the personal breathing zone. Symptoms were inco nsistently related to dust concentrations in the personal breathing zone.