Centro de Energia Nuclear na Agricultura, Universidade de São Paulo - CENA/USP, Avenida Centenário, 303, São Dimas, Piracicaba, São Paulo 13416-000, Brazil.
Centro Universitário Hermínio Ometto - FHO/UNIARARAS, Av. Dr. Maximiliano Baruto, Araras, São Paulo 13607-339, Brazil.
Chemosphere. 2015 Aug;132:206-12. doi: 10.1016/j.chemosphere.2015.02.053. Epub 2015 Apr 17.
Florfenicol (FLC) and oxytetracycline (OTC) are the two most commonly used antibiotics for bacterial treatment in fish farming in Brazil, and because of their intensive use, the potential harmful effects on aquatic organisms are of great concern. This study evaluated the effects of environmental concentrations of FLC and OTC on the genetic material of juvenile tilapia (Oreochromis niloticus) erythrocytes by using the comet assay and the occurrence of micronuclei (MN) and other erythrocytic nuclear abnormalities (ENAs) after exposure to 96hour. The comet assay showed that fish erythrocytes exhibited significantly higher DNA damage after exposure to environmental concentrations of FLC and OTC. Although MN was not observed, ENAs were significantly higher after exposure to FLC, indicating that ENAs are a better biomarker for FLC than MN. The results showed that environmental concentrations of FLC and OTC were genotoxic to erythrocytes of O. niloticus; however, future studies on DNA damage recovery are needed.
氟苯尼考（FLC）和土霉素（OTC）是巴西水产养殖中用于细菌治疗的两种最常用的抗生素，由于其大量使用，对水生生物的潜在有害影响引起了极大关注。本研究通过彗星试验评估了环境浓度的 FLC 和 OTC 对幼年罗非鱼（Oreochromis niloticus）红细胞遗传物质的影响，并在暴露 96 小时后观察微核（MN）和其他红细胞核异常（ENAs）的发生。彗星试验表明，暴露于环境浓度的 FLC 和 OTC 后，鱼红细胞的 DNA 损伤明显增加。尽管未观察到 MN，但暴露于 FLC 后 ENAs 明显升高，表明与 MN 相比，ENAs 是 FLC 的更好生物标志物。结果表明，环境浓度的 FLC 和 OTC 对 O. niloticus 的红细胞具有遗传毒性；然而，需要进一步研究 DNA 损伤的恢复。
