title: 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.
authors.affiliation: BioDetection Systems B.V. (BDS), Badhuisweg 3, 1031 CM Amsterdam, The Netherlands. harrie.besselink@bds.nl
authors.forename: Harrie T
authors.initials: HT
authors.lastname: Besselink
authors.forename: Cor
authors.initials: C
authors.lastname: Schipper
authors.forename: Hans
authors.initials: H
authors.lastname: Klamer
authors.forename: Pim
authors.initials: P
authors.lastname: Leonards
authors.forename: Henk
authors.initials: H
authors.lastname: Verhaar
authors.forename: Emiel
authors.initials: E
authors.lastname: Felzel
authors.forename: Albertinka J
authors.initials: AJ
authors.lastname: Murk
authors.forename: John
authors.initials: J
authors.lastname: Thain
authors.forename: Kazunori
authors.initials: K
authors.lastname: Hosoe
authors.forename: Greet
authors.initials: G
authors.lastname: Schoeters
authors.forename: Juliette
authors.initials: J
authors.lastname: Legler
authors.forename: Bram
authors.initials: B
authors.lastname: Brouwer
mesh_terms: D000818:Animals; D001530:Belgium; D001681:Biological Assay; D002138:Calibration / Q000592:standards; D045744:Cell Line, Tumor; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000032:analysis*; D007564:Japan; D007753:Laboratories / Q000592:standards; D008156:Luciferases / Q000032:analysis; D009426:Netherlands; D000072317:Polychlorinated Dibenzodioxins / Q000032:analysis*; D051381:Rats; D015203:Reproducibility of Results; D006113:United Kingdom; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000072317:Polychlorinated Dibenzodioxins; D014874:Water Pollutants, Chemical; D008156:Luciferases