Developmental Toxicities in Zebrafish Embryos Exposed to Tri-o-cresyl Phosphate

As a widely used plasticizer and fire retardant, tri-o-cresyl phosphate has been commonly found in global water sources, sediments and biota. However, its potential toxicity to aquatic organisms is not fully understood. Here, we assessed its developmental effects by use of a zebrafish (Danio rerio) model at tri-o-cresyl phosphate concentrations between 0.15 and 88.5 μg/L. Diverse impairments of zebrafish embryos, such as altered morphological and physical characteristics and locomotor behaviors, were observed at different tri-o-cresyl phosphate concentrations. Furthermore, swimming behaviors were significantly inhibited at tri-o-cresyl phosphate concentrations ranging from 3.0 μg/L to 88.5 μg/L. The swimming activity during light-to-dark transition significantly increased at tri-o-cresyl phosphate concentrations of 14.5 μg/L to 88.5 μg/L. Taken together, our present data help to clarify the potential developmental toxicity of tri-o-cresyl phosphate that was not yet fully recognized, and thus contribute to its environmental risk assessment.