CALUX bioassay: a cost-effective rapid screening technique for screening dioxins like compounds.

Xenobiotic detection systems-chemically activated luciferase expression (XDS-CALUX) bioassay in determining the toxic equivalency (TEQ) of PCDD/Fs from contaminated sites reported in several papers has been discussed in this study. CALUX bioassay method has been validated by an effective combined column clean-up system followed by addition of samples to monolayer cell cultures of H1L6.1c3 cell line in 96 well plates. Cultures are then examined under microscope after 24 h incubation followed by rinsing with 75 μL phosphate buffer saline and 30 μL of cell culture lysis. The response is observed in the luminometer and expressed in relative light unit (RLUs). CALUX-TEQ is estimated from a TCDD standard curve for unknown samples. Quality control in CALUX is done by selecting the range of CALUX values falling in the center of the linear standard curve. For developing nations CALUX biossay can be used as a cost effective and rapid screening technique for screening xenobiotic compounds from the hotspots like open solid waste burning sites, informal e-waste recycling workshops and industrial zones where constant monitoring for such compounds is required.