Bioaccumulation and Biotransformation of BDE‐47 Using Zebrafish Eleutheroembryos (Danio rerio)

Abstract

Polybrominated diphenyl ethers (PBDEs) industrially used as ame retardants are nowadays considered emerging pollutants as they are endocrine disrupting chemicals (EDCs), persistent in the environment, bioaccumulative and in addition, its hydroxylated (OH-BDEs) and methoxylated (MeO-BDEs) metabolites have similar ecotoxic properties. The aim of this work was to develop an analytical method to be applied in the study of the bioconcentration and biotransformation of BDE-47 due to its bioavailability, toxicity and high persistence and abundance in environmental samples, including humans. So, a dependable ultrasonic extraction process followed to dispersive SPE clean-up step and GC-MS-μECD detection has worked out for the determination of BDE-47 and its main biotransformation products (MeO-BDEs and OH-BDEs), considering the polarity difference. In addition, an alternative method to bioconcentration o cial guideline OECD 305, developed previously with zebra sh (Danio rerio) eleutheroembryos (i.e., hatched but not yet free feeding embryos) is used, reducing dramatically the animal suffering but also time and reagents. Bioconcentration factors (BCF) were calculated using rst order one-compartment toxicokinetic model. The pro les found show rapid absorption in the rst hours of larval development and great bioaccumulative with capacity, nding bioconcentration factors (BCF) of 6631 and 44210 at nominal concentrations of 10 and 1 μg•L -1 (< 1% LC50), respectively. Metabolization studies show increasing concentrations of the metabolites BDE-28, 2'-OH-BDE-28 and 5-MeO-BDE-47 throughout the exposure time. The results obtained show the feasibility of the method for bioaccumulation and opens the possibility of metabolic studies with zebra sh eleutheroembryos, which is a very underdeveloped eld without o cial testing or regulation.

Miniaturized method for the quantification of persistent organic pollutants and their metabolites in HepG2 cells: assessment of their biotransformation

“…For the same reason, the unidentified compounds are more hydrophobic metabolites and therefore they could not be removed from the environment during the experiment. A significant concentration of BDE-28 was detected in cell samples such as what we also observed in a previous zebrafish eleutheroembryo biotransformation study with these same compounds [52]. One of the major biotransformation metabolites of BDE-47 is BDE-28 by loss of bromine in the ortho position [53].…”