Compatibilitty of the cyclone BC-112 with the measurement of endotoxins in bioaerosols : A study in laboratory conditions

The BC-112 cyclone is an individual bioaerosol sampler with of a metallic main body (2 mm inlet), a first collection stage (1.5 ml collection tube) and a final collection stage (37 mm three pieces cassette). A laboratory study has been carried out with E. coli experimental bioaerosols in order to find out if the BC-112 cyclone could be used for sampling of airborne endotoxins. A first set of experiments allowed the validation of a protocol for the removal of endotoxins form contaminated BC-112 cyclones. A second set of has showed that the filter used in the final stage of the sampler had a significant (p<0.005) effect on the measured concentrations of airborne endotoxins. A last set of assays allowed a side by side comparison of the BC-112 cyclone and the closed-face cassette (both with PVC filter) upon a wide range of concentrations and revealed a significant correlation (r=0.87; n=9; p=0.001) between the two methods. The BC-112 cyclone/cassette ratio was from 0.65 to 1.42. The results indicate that the BC-112 cyclone is suitable for the assessment of airborne endotoxins providing protocol adaptations.