Table 2.

Comparison of bisphenol A (BPA) and 17β-estradiol (E2) toxicity studies conducted in the larval zebrafish model. Note: the caudal fin defect observed by Duan et al. (2008) was the only abnormality from among the other studies that was not observed in our study at some concentration.

Study	Kishida et al. 2001		Duan et al. 2008	McCormick et al. 2010	Fei et al. 2010	Gibert et al. 2011	This study
Chemical	BPA	E2	BPA	BPA	BPA	BPA	BPA	E2
Exposure Protocol	Batch (40-50) exposure in 50 ml, daily solution renewal, DMSO vehicle, 2-72 hpf	Batch (40-50) exposure in 50 ml, daily solution renewal, DMSO vehicle, 2-72 hpf	Individual exposure in 2ml, EtOH vehicle, 8-72 hpf	Batch exposure, 48 hours	Batch (15) exposure in 25 ml, DMSO vehicle, 2-96 hpf	aExposure protocol not clear, 5-48 hpf	Individual exposure in 100 μl, 8-120 hpf	Individual exposure in 100 μl, 8-120 hpf
LC 50	-	-	~73 μM (24hpf)	-	-	-	>70 μM (120hpf)	>25 μM (120hpf)
NOAEC	-	-	9 μM (72hpf)	-	-	-	30 μM (120hpf)	0.1 μM (120hpf)
Abnormalities at LOAEC	-	50% hatching delays at 10uM	Edema, delayed hatching	15uM (48hpf) edema	30uM (48hpf) edema	>5uM (48hpf) otolith	>30uM (120hpf)	40% yolk sac edema at 10uM
Mortality	20 μM, (statistical significance not reported)	80% at 10μM	Significant at 24hpf	Reported at 28 dpf for 5 (47%), 10 (22%), 15 (47%) μM	Observed at 30 μM at 48 hpf	Observed at 100 μM	None ~73uM (120hpf)	None 25uM (120hpf)
Notable abnormalities compared across studies	Curved tail down phenotype, but statistical significance not reported	Delayed hatch, pericardial edema, yolk sac edema, curved tail down	Pericardial edema and hatching delays, caudal fin defect	Pericardial edema	bYolk sac & pericardial edema, uninflated swim bladder, delayed hatch	Otolith defects (50% of embryos at 25 μM)	Pericardial edema, delayed hatch, otolith defects >40uM	Pericardial edema, yolk sac edema, curved tail down

hpf: hours post fertilization; dpf: days post fertilization; NOAEC: no observed adverse effect concentration; LOAEC: lowest observed adverse effect concentration; LC₅₀: concentration producing 50% mortality

^aGibert et al. (2011) did not clearly state whether embryos were batch or individually exposed for the toxicity assay. Also, it is unclear whether the vehicle used was DMSO or ethanol (EtOH).

^bFei et al. reported abnormalities at 7 dpf.