Work Area Measurements as Predictors of Personal Exposure to Endotoxin and Cotton Dust in the Cotton Textile Industry

Objectives: To determine if work area measurements of endotoxin and/or cotton dust obtained from the vertical elutriator (VE) can be used to predict levels of personal endotoxin exposure as measured by the Institute of Occupational Medicine (IOM) inhalable dust sampler in the cotton textile industry. Methods: Fifty-six work area cotton dust samples were collected from 14 areas and 82 per-sonal cotton dust samples were collected from 41 workers in three textile mills (Mills A, B and C) in Shanghai, China. Cotton dust concentrations were determined gravimetrically from sam-ple filters, of which endotoxin concentrations were determined using a kinetic chromogenic modification of the limulus amoebocyte lysate assay. Linear regression models were used to de-termine the association between log IOM personal endotoxin concentration and log VE area endotoxin concentration. Results: Median cotton dust and endotoxin concentrations measured from VE area samples in the three mills were 0.36 mg m23 and 1280.76 endotoxin units per cubic meter (EU m23), respectively, compared to 1.74 mg m23 and 2226.83 EU m23 from IOM personal samples. Ex-cluding samples from weaving processes, we observed linear associations between VE are