RESEARCH ARTICLE Effects of polycyclic aromatic hydrocarbons on biomarker responses in Gambusia yucatana, an endemic fish from Yucatán Peninsula, Mexico Letícia Aguilar 1 & Maurílio Lara-Flores 2 & Jaime Rendón-von Osten 2 & Jorge A. Kurczyn 3 & Bruno Vilela 4 & André Luis da Cruz 1 Received: 24 June 2020 /Accepted: 12 April 2021 # The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2021 Abstract Polycyclic aromatic hydrocarbons (PAHs) are petroleum components that, when dissolved in the aquatic environment, can disrupt normal animal physiological functions and negatively affect species populations. Gambusia yucatana is an endemic fish of the Yucatán Peninsula that seems to be particularly sensitive to the presence of PAHs dissolved in the water. Here, we examined PAH effects on gene expressions linked to endocrine disruption and biotransformation in this species. Specifically, we examined the expression of vitellogenin I (vtg1), vitellogenin II (vtg2), oestrogen receptor α (esr1), oestrogen receptor β (esr2), aryl hydrocarbon receptor (AhR) and the cytochrome P4503A (CYP3A) genes. We exposed G. yucatana to different concentrations of PAHs (3.89, 9.27, 19.51 μg/L) over a period of 72 h and found changes associated with reproduction, such as increases in hepatic expression of vtg, esr, AhR and CYP3A, mainly at concentrations of 9.27 and 19.51 μg/L. Our results also indicate that benzo[a]pyrene was probably the main PAH responsible for the observed effects. The genes examined here can be used as molecular markers of endocrine-disrupting compounds, as the PAHs, present in the environment, as gene expression increases could be observed as early as after 24 h. These biomarkers can help researchers and conservationists rapidly identify the impacts of oil spills and improve mitigation before the detrimental effects of environmental stressors become irreversible. Keywords Water contamination . Environmental stressors . Polycyclic aromatic hydrocarbons . Endocrine disruptors . Biotransformation . Benzo[a]pyrene Introduction The release and discharge of petroleum and its chemical prod- ucts are increasing worldwide (Walter et al., 2019), affecting sea and freshwater ecosystems due to the long-lasting effects of these pollutants (Zabbey and Olsson, 2017). Polycyclic aromatic hydrocarbons (PAHs) are a family of compounds present among the petroleum components. They are Responsible Editor: Philippe Garrigues * André Luis da Cruz cruz.andre@ufba.br Letícia Aguilar aguilarleticiafisio@gmail.com Maurílio Lara-Flores maurlara@uacam.mx Jaime Rendón-von Osten jarendon@uacam.mx Jorge A. Kurczyn JKurczynR@iingen.unam.mx Bruno Vilela bvilela.bv@gmail.com 1 Institute of Biology, Laboratory of Animal Physiology, Federal University of Bahia, Rua Barão de Jeremoabo 147, Salvador, Bahia CEP 40.170-115, Brazil 2 Institute of Ecology, Fisheries and Oceanography of the Gulf of Mexico, Laboratory of Ecotoxicology, Autonomous University of Campeche, Av. Héroe de Nacozari 480, C.P. 24029, San Francisco de Campeche, Campeche, Mexico 3 Institute of Engineering, Coastal Engineering and Processes Laboratory, National Autonomous University of Mexico, Puerto de Abrigo s/n, 97356 Sisal, Yucatán, Mexico 4 Institute of Biology, Spatial Ecology Laboratory, Federal University of Bahia, Rua Barão de Jeremoabo 147, Salvador, Bahia CEP 40.170-115, Brazil Environmental Science and Pollution Research https://doi.org/10.1007/s11356-021-13952-0