Intra‐ and interlaboratory calibration of the DR CALUX® bioassay for the analysis of dioxins and dioxin‐like chemicals in sediments

Abstract

In the Fourth National Policy Document on Water Management in The Netherlands, it is defined that in 2003, in addition to the assessment of chemical substances, special guidelines for the assessment of dredged material should be recorded. The assessment of dredged material is based on integrated chemical and biological effect measurements. Among others, the DR CALUX (dioxin responsive-chemically activated luciferase expression) bioassay has tentatively been recommended for inclusion in the dredged material assessment. To ensure the reliability of this bioassay, an intra- and interlaboratory validation study, or ring test, was performed, organized by the Dutch National Institute for Coastal and Marine Management (RIKZ) in cooperation with BioDetection Systems BV (BDS). The intralaboratory repeatability and reproducibility and the limit of detection (LOD) and quantification (LOQ) of the DR CALUX bioassay were determined by analyzing sediment extracts and dimethyl sulfoxide (DMSO) blanks. The highest observed repeatability was found to be 24.1%, whereas the highest observed reproducibility was calculated to be 19.9%. Based on the obtained results, the LOD and LOQ to be applied for the bioassay are 0.3 and 1.0 pM, respectively. The interlaboratory calibration study was divided into three phases, starting with analyzing pure chemicals. During the second phase, sediment extracts were analyzed, whereas in the third phase, whole sediments had to be extracted, cleaned, and analyzed. The average interlaboratory repeatability increased from 14.6% for the analysis of pure compound to 26.1% for the analysis of whole matrix. A similar increase in reproducibility with increasing complexity of handlings was observed with the interlaboratory reproducibility of 6.5% for pure compound and 27.9% for whole matrix. The results of this study are intended as a starting point for implementing the integrated chemical-biological assessment strategy and for systematic monitoring of dredged materials and related materials in the coming years.

The Distribution of the MusselMytilusSpecies Along the Norwegian Coast

“…Good correlations were usually observed between DRLuc/CALUX bioassay results obtained on marine biological matrices and results obtained from use of advanced chemical methods (Windal et al, 2002;Hoogenboom, 2004). An intra-and interlaboratory study using CALUX for analysis of dioxins and dioxin-like chemicals in dredged sediments also concluded that the tool was accurate and reliable for monitoring of coastal sediments (Besselink et al, 2004).…”

“…It has been shown that frequent participation in interlaboratory exercises improves performance (De Boer et al, 1996;Besselink et al, 2004), but there remains a need for QA to be established as routine within international programmes such as BEQUALM.…”

Effect-based assessment of persistent organic pollutant and pesticide dumpsite using mammalian CALUX reporter cell lines

“…The DR CALUX was developed for the detection of stable dioxins and dioxin-like compounds. To this end, sample extracts are acid treated to remove acid-labile compounds and incubations are performed for 24 h to allow for additional removal of compounds that are less metabolically stable (Besselink et al 2004). The PAH CALUX was specifically developed for the detection of less metabolically stable AhR ligands, in particular carcinogenic PAHs (Pieterse et al 2013).…”

Prolonged ELS test with the marine flatfish sole (Solea solea) shows delayed toxic effects of previous exposure to PCB 126

“…Therefore, a very sensitive in vitro reporter gene assay for dioxin-like toxic potency in H4IIE rat hepatoma cells (Murk et al, 1998) was applied for the direct quantification of the in vitro TCDD-equivalent (TEQ) levels on a lipid basis in these very small samples. This DRE-H4IIE.Luc assay (sometimes also referred to as DR CALUX) has been chemically validated before and produces a response that is linear with the concentration of compounds with dioxin-like toxicity (Murk et al, 1998;Stronkhorst et al, 2002;Besselink et al, 2004;Hoogenboom et al, 2006;Van Leeuwen et al, 2007).…”