It has been shown that coal dust exposure stimulates inflammatory response leading to increased release of cytokines from monocytes such as TNF-alpha and IL1 These released cytokines play the key role in the pathogenesis of pneumoconiosis including coal workers' pneumoconiosis. In this study, we investigated TNFA, IL1A, IL1B and IL1RA genes variations on basal, lipopolysaccharide and coal dust-induced cytokine release from blood monocytes of homozygous allele and minor variant allele carriers in Turkish coal workers and CWP patients. According to the genotyping results, TNFA -238 gene polymorphism was found as a risk factor in CWP development (OR=3.79) and to in vitro results; release of both TNF-alpha and IL1 cytokines from the monocytes in CWP patients was significantly increased compared to the healthy workers. Also. LPS and coal dust stimulated release of TNF-alpha, which was significantly higher in allele 2 carriers compared to subjects carrying allele 1 in both the groups. These data suggest that the coal dust-induced release of TNF-alpha from monocytes may be a useful biomarker of CWP. (C) 2009 Elsevier GmbH. All rights reserved.