Triphenyl Phosphate at Environmental Levels Retarded Ovary Development and Reduced Egg Production in Japanese Medaka (Oryzias latipes)

Abstract

Since triphenyl phosphate (TPhP) elicits both antiestrogenic activities via blocking the estrogen receptor (ER) and estrogenic activity by elevating 17β-estradiol (17β-E2) synthesis, its adverse effect on female reproduction is uncertain. In this study, we exposed Japanese medaka to TPhP at 131, 363, and 1773 ng/L for 100 days following hatching. TPhP significantly induced ovary retardation in all exposure groups (incidence: from 11.9 to 37.8%) and reduced egg production by 38.9 and 50.9% in the 363 and 1773 ng/L exposure groups, respectively. Vitellogenin (vtg) transcription was significantly downregulated by 35.4–57.4% after TPhP exposure, explaining the ovary retardation. Considering that 17β-E2 was only significantly decreased in the 1773 ng/L exposure group, ER antagonism could be the dominant contributor to the inhibition of vtg transcription and female reproductive toxicity of TPhP. As 4-hydroxyphenyl diphenyl phosphate, a metabolite of TPhP, was detected in livers with similar concentration [68.4–1237 ng/g lipid weight (lw)] to that of TPhP (485–1594 ng/g lw) and elicited medaka ER antagonistic activity (50% inhibitory concentration = 78.1 μM), TPhP and its metabolite should both contribute to the reproductive inhibition. We demonstrate that TPhP at environmentally relevant concentrations is toxic to female reproduction, which poses an ecological risk to wild fish at the population level.

Maternal Transfer of 2-Ethylhexyl Diphenyl Phosphate Leads to Developmental Toxicity Possibly by Blocking the Retinoic Acid Receptor and Retinoic X Receptor in Japanese Medaka (Oryzias latipes)

“…The time-point-sampled embryos collected in seven days were pooled to obtain sufficient embryos to determine the embryonic concentrations of EHDPP and its metabolite. After 35 days of exposure, the females were sacrificed, and the brain, liver, muscles, and ovary were sampled as described in our previous study 33 to determine EHDPP concentrations for better understanding the maternal transfer of EHDPP and whether the exposure level used in this study is comparable with those reported in wild fish. The detailed experimental design can be found in Figure S1.…”

WITHDRAWN: Exposure to Difenoconazole Induces Reproductive Toxicity of Zebrafish by Interfering Reproductive Behavior

“…As we all know, reproductive ability is essential for the continuation of a population, and the number of a population is also of great signi cance to the stability of the ecosystem (Arcand-Hoy and Benson, 1998; Nassar and Fahmy, 2016). However, environmental pollutants often induced reproductive toxicity by interfering with gamete formation, such as bisphenol compounds (Ji et (Li et al, 2019b). In vertebrates, sexual behavior coordinates the release of gametes to determine fertility (Mitchell et al, 2020).…”

In Vivo Characterization of the Toxicological Properties of DPhP, One of the Main Degradation Products of Aryl Phosphate Esters

“…2018 ; Meeker and Stapleton 2010 ; Meeker et al. 2013 ), water ( Li et al. 2019a ), or air ( Wei et al.…”