TITLE:
Toxicity Evaluation of Acrylamide on the Early Life Stages of the Zebrafish Embryos (Danio rerio)
AUTHORS:
Hattie Spencer, Joseph Wahome, Mary Haasch
KEYWORDS:
Acrylamide, Toxicity, Zebrafish, Malformation, Embryonic Development
JOURNAL NAME:
Journal of Environmental Protection,
Vol.9 No.10,
September
7,
2018
ABSTRACT: Acrylamide
is a chemical used mainly in industrial applications and the treatment of
drinking and wastewater, making it easy to enter aquatic ecosystems. There are
few studies known about the toxicity of acrylamide to aquatic organisms which
have shown evidence of a number of histopathological effects. To assess the
effects of acrylamide to freshwater fish, Zebrafish (Danio rerio)
embryos were exposed to serial concentrations of acrylamide (0, 100, 300, and 500 mg/L) to investigate the acute
toxicity effects on teleost embryogenesis. Embryos less than 24 hrs old were
exposed under static non-renewal conditions for ten days or until hatching. The
toxic endpoints evaluated include: egg/embryo viability, hatchability, and
morphological/developmental anomalies during organogenesis. The acute toxicity
test resulted in a 48 h-LC50 of 585 mg/L for egg viability. Exposure of embryos
significantly reduced hatchability and larval survival, in a concentration
dependent manner. Dimethyl sulfoxide (DMSO) was used as a solvent carrier to
permeate the uptake of acrylamide through the chorion membrane. No significant
damages or
complications were observed in embryos exposed to DMSO. At 500 mg/L, the
highest test concentration, the survival of embryos was greatly reduced within
24 hrs of exposure. The lower test, 100 mg/L, produced a significant number of
developmental anomalies to the Zebrafish that included dorsal tail flexure,
severe pericardial edema, facial and cranial defects and decreased heartrate
(40 bpm). Premature hatching of embryos and developmental arrest was observed
in all concentrations. The severity of these anomalies was
concentration-dependent and resulted in low survival rate and high frequency of
malformations. These results indicate that acrylamide is teratogenic and
provide support for sub-lethal toxicity testing using Zebrafish embryos.