Assessing differences in toxicity and teratogenicity of three phthalates, Diethyl phthalate, Di-n-propyl phthalate, and Di-n-butyl phthalate, usingXenopus laevisembryos

Abstract

Phthalates, compounds used to add flexibility to plastics, are ubiquitous in the environment. In particular, the diethyl (DEP), di-n-propyl (DnPP), and di-n-butyl (DBP) phthalates were found to exert detrimental effects in both mammalian and non-mammalian studies, with toxic effects varying according to alkyl chain length. Embryos of Xenopus laevis, the African clawed frog, have been used to assess toxicity and teratogenicity of several compounds and serves as a model for assessing adverse and teratogenic effects of ortho-phthalate esters. The purpose of this study was to develop a model for comparison of developmentally toxic effects of ortho-phthalate esters using Xenopus embryos. In this study developing Xenopus laevis embryos were exposed to increasing concentrations of DEP, DnPP, and DBP using the 96-h Frog Embryo Teratogenesis Assay-Xenopus (FETAX), with 96-h lethal concentrations, effective concentrations to induce malformations, teratogenic indices, and concentrations to inhibit growth determined. DEP, DnPP, and DBP showed enhanced toxicity with increasing ester length. Developing Xenopus laevis exposed to DEP, DnPP, and DBP showed similar malformations that also occurred at lower concentrations with increasing alkyl chain length. Teratogenic risk did not change markedly with alkyl chain length, with data showing only DBP to be teratogenic.

Acute toxicity and responses of antioxidant systems to dibutyl phthalate in neonate and adultDaphnia magna

“…Organisms in the early developmental stages have been reported to be less tolerant to the detrimental effects of pollutants (Huang, Li & Yang, 2016). Many recent publications showed the teratogenic nature of DBP, reporting malformations in developing Zebrafish Danio rerio , the African clawed frog Xenopus laevis , and embryos of the polychaete Galeolaria caespitosa (Xu et al, 2015; Gardner et al, 2016; Lu, Lin & Aitken, 2017). Environmental exposure may lead to DBP accumulation during the neonatal stage, which negatively impacts various future developmental characteristics (Khalil, Elhakim & EL-Murr, 2016).…”

Identification of 15 Phthalate Esters in Commercial Cheese Powder via Cyclodextrin-Promoted Fluorescence Detection

“…Phthalate esters chosen for analysis (compounds 1 – 15 , Figure 2) include those that have been found in macaroni and cheese powder 25 as well as a variety of other analogues, with the goal of determining the generality of the fluorescence-based method and GC–MS-based analysis across a broad swath of structures with a relatively wide range of potential toxicities. 26 For the fluorescence-based detection method, we selected γ-cyclodextrin as the supramolecular host due to the known ability of cyclodextrin to bind hydrophobic small molecules in its interior 27 and the specific ability of γ-cyclodextrin to facilitate the binding of two small-molecule guests to form a ternary complex. 28 A commercially available boron-dipyrromethene (BODIPY) fluorophore was selected as the source of the read-out signal, based on the well-documented ability of BODIPY fluorophores to display high quantum yield and robust performance under a variety of experimental conditions.…”

Phthalates modulate steroid 5-reductase transcripts in the Western clawed frog embryo

“…Other studies have also observed that phthalate exposures to similar concentrations as used in this study resulted in malformed animals. For example, exposure to DBP and DEP at concentrations exceeding 500 µg/L significantly increased malformations, including abnormal gut coiling, cardiac abnormalities, and malformed faces, eyes, and brains in X. laevis (Bantle et al, 1999;Gardner et al, 2016). Furthermore, S. tropicalis exposed to dimethyl phthalate (DMP) and dicyclohexyl phthalate (DCHP) also resulted in malformations, such as edemas, improperly developed hearts, tail abnormalities, improperly coiled guts, and/or absent gills (Mathieu-Denoncourt et al, 2016).…”