Prenatal Exposure to Copper Sulfate: Effects on Fetal Development in Rats

Abstract Copper sulfate is a pesticide widely used in Türkiye to treat bacterial and fungal infections on various fruit and nut trees. Despite its widespread use, insufficient data are available regarding its potential teratogenic and toxic effects during pregnancy. This study aimed to investigate the organ oxidative stress, immunohistochemistry, histopathology, and genetic effects of copper sulfate exposure in rat fetuses during pregnancy. Pregnant Wistar rats were administered 100 mg/kg copper sulfate daily via oral gavage throughout gestation. Fetuses were collected on day 21 of gestation and subjected to double skeletal staining to assess bone development. Additionally, fetal organ samples (liver, kidney, lung, brain, placenta, and heart) were analyzed histologically by Hematoxylin–Eosin (H&E) staining and immunohistochemically for inflammatory markers such as Tumor Necrosis Factor-Alpha (TNF-α), Nuclear Factor Kappa B (NF-κB), and Interleukin-6 (IL-6), and mRNA analysis was performed using real-time PCR for TNF-α , IL-6 , and NF-κB . Oxidative stress was assessed using ELISA and biochemical assays for malondialdehyde (MDA), total antioxidant status (TAS), and total oxidant status (TOS). In the copper sulfate groups, compared to the control group, an increase in the number of degenerative glomeruli in the kidney and inflammatory cell infiltrations in the heart tissue, more frequent bleeding and cell infiltrations in the lungs, and an increase in the number of degenerative neurons in the brain and both giant trophoblast cells and glycogenic trophoblast cells in the placenta were observed. Immunohistochemical analyses revealed a significant increase in proinflammatory markers, including TNF-α, NF-κB, and IL-6, in fetal tissues in the copper sulfate-exposed group. Biochemical assessments showed a significant decrease in TAS and increases in MDA and TOS levels, indicating a marked oxidative stress state in all tissues examined. Furthermore, skeletal staining analyses revealed significant impairments in bone development in fetuses in the copper sulfate-exposed group compared to the control group. These findings suggest that prenatal copper sulfate exposure may cause significant histological damage, inflammatory responses, oxidative stress, and skeletal development in rat fetuses. Given the widespread use of copper sulfate in agriculture and the potential for human exposure, particularly among pregnant women in agricultural regions, further research is needed to reveal the full extent of its developmental toxicity.