Chronic toxicity evaluation of the flame retardant tris (2-butoxyethyl) phosphate (TBOEP) using Daphnia magna transcriptomic response.

Abstract Tris (2-butoxyethyl) phosphate (TBOEP) is an organophosphorous-containing flame retardant (OPFR) of high production volume used in a broad range of applications. The use of TBOEP containing products has resulted in its release and ubiquitous occurrence in the aquatic environment. In this study, Daphnia magna transcriptomic response was measured by microarray to evaluate sublethal effects of TBOEP as part of a multi-level biological approach including specific gene transcription measured by qRT-PCR, enzyme activity, and life-history endpoints (i.e., survival, growth and reproduction). Chronic exposure (21 d) to a range of sublethal concentrations of TBOEP (14.7–1470 μg L −1 ) did not impact growth, survival or reproduction, although the number of offspring decreased between the lowest and the highest dose. Gene transcription profiling by microarray analysis revealed that 101 genes were differentially transcribed in response to TBOEP (fold change treated/control ±1, p D. magna as a first line of evidence to unravel the mode of action of chemicals.