Inhalable dust, endotoxins and (1-3)-β-d-glucans as indicators of exposure in waste sorting plant environment

The aim of the study was to assess the levels of inhalable dust, endotoxins and (1-3)-β-d-glucans as agents harmful to the respiratory tract of workers of municipal waste sorting plants and interaction between these agents based on the measurements taken in two plants with different processing capacities. The study was conducted in summer season in two waste sorting plants (WSPs) differing in processing capacity. Samples of bioaerosol for inhalable dust (gravimetric method), endotoxins (LAL test in kinetic, chromogenic version) and (1-3)-β-d-glucans (Glucatell test in kinetic version) were collected from 42 sorting workers using individual aspirators with glass fiber filters during the work shift. Average geometric concentrations (geometric standard deviation; min-max) of inhalable dust, endotoxins and (1-3)-β-d-glucans were: WSP1: 1.7 mg m^-3 (2.2; 0.6-6.9 mg m^-3); 15.9 ng m^-3 (2.1; 5.4-78.9 ng m^-3), 55.1 ng m^-3 (1.8; 20.7-188.6 ng m^-3) and WSP2: 0.8 mg m^-3 (2.2; 0.2-3.8 mg m^-3), 9.8 ng m^-3 (2.4; 1.6-29.7 ng m^-3), 45.0 ng m^-3 (3.2, 5.7-212.9 ng m^-3), respectively. A significantly higher concentration of inhalable dust was recorded in WSP1 with bigger processing capacity compared to WSP2 (less processing capacity). Significant (p < 0.05) and very high correlations (Spearman rank R > 0.7) were found between the concentrations of all analyzed harmful agents. Processing capacity of waste sorting plants differentially affects the concentrations of inhalable dust, whereas concentrations of endotoxins and glucans are less clearly affected. This suggests that relative concentrations of endotoxin and glucan are depending on the waste sorting capacity.