Developmental and neurotoxic effects of dimethyl phthalate on zebrafish embryos and larvae

Weili Yang; Ruijing Li; Xingxue Yan; Pengkai Fan; Weyland Cheng; Cuihua Liu; Yaodong Zhang; Jitong Li

doi:10.1016/j.aquatox.2025.107241

Developmental and neurotoxic effects of dimethyl phthalate on zebrafish embryos and larvae

Aquat Toxicol. 2025 Jan 6:279:107241. doi: 10.1016/j.aquatox.2025.107241. Online ahead of print.

Authors

Weili Yang¹, Ruijing Li¹, Xingxue Yan¹, Pengkai Fan², Weyland Cheng¹, Cuihua Liu³, Yaodong Zhang⁴, Jitong Li⁵

Affiliations

¹ Henan Engineering Research Center of Zebrafish Models for Human Disease and Drug Screening, Henan Neurodevelopment Engineering Research Center for Children, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou 450018, China.
² Key Laboratory of Pediatric Hematology of Henan Province, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou 450018, China.
³ Department of Nephrology and Rheumatology, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou 450018, China.
⁴ Henan Engineering Research Center of Zebrafish Models for Human Disease and Drug Screening, Henan Neurodevelopment Engineering Research Center for Children, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou 450018, China. Electronic address: [email protected].
⁵ Henan Engineering Research Center of Zebrafish Models for Human Disease and Drug Screening, Henan Neurodevelopment Engineering Research Center for Children, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou 450018, China; Department of Nephrology and Rheumatology, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou 450018, China. Electronic address: [email protected].

PMID: 39799758
DOI: 10.1016/j.aquatox.2025.107241

Abstract

Dimethyl phthalate (DMP) has been extensively utilized as a plasticizer on a global scale for many years. Its presence in the environment and its harmful effects on living organisms have raised concerns. This study aimed to examine its potential developmental neurotoxicity by utilizing zebrafish as a model. Zebrafish embryos were exposed to different concentrations of DMP (5-100 mg/L) from 4 to 120 h post-fertilization (hpf). The survival, hatching, and malformation rates were recorded for each group. Behavioral analysis was conducted on zebrafish larvae, and transgenic zebrafish Tg(elavl3:EGFP) were used to assess the impact of DMP on neuronal cells. The mRNA levels of key neurological marker genes were evaluated at 96 hpf of DMP exposure. The study revealed that exposure to DMP resulted in decreased survival and hatching rates in zebrafish. Embryos treated with 50 mg/L of DMP exhibited lower average survival rates (72.78-78.33%) between 24-96 hpf, while treatment with 25-50 mg/L of DMP resulted in reduced hatching rates (39.44% and 2.22%, respectively) at 48 hpf compared to the control group. Moreover, exposure to 25-50 mg/L of DMP caused an increase in malformations, such as tail curvature, spinal curvature, yolk sac edema and pericardial edema. Interestingly, at 24 hpf, DMP also resulted in an increase in spontaneous tail coiling in zebrafish embryos, as well as a decrease in their swimming distance at 120 hpf. Furthermore, treatment with 50 mg/L of DMP led to a decrease in the fluorescence intensity of transgenic zebrafish Tg(elavl3: EGFP). RT-qPCR analysis showed a significant down-regulation of marker genes (gap43, mbp, α1-tubulin, syn2a) associated with nervous system function in DMP-treated zebrafish. Overall, these findings offer a thorough understanding of the mechanisms underlying the neurotoxicity caused by DMP, highlighting the risk of DMP on developmental and neurotoxic effects in zebrafish. Therefore, strict supervision of DMP use and release is essential to safeguard ecological and aquatic organisms.

Keywords: Acute exposure; Behavior; Developmental toxicity; Dimethyl phthalate; Neurological damage; Zebrafish larvae.