Asia Pacific Journal of Medical Toxicology

Chronic Exposure to Polyethylene Terephthalate Microplastics Induces Endocrine and Inflammatory Dysregulation in Female Albino Rats: Implications for Reproductive and Public Health

Document Type : Original Article

Authors

Godae Fidelis Beega 1
Kemzi Nosike Elechi-Amadi 2
Edna Ogechi Nwachukwu 2

1 Department of Medical Laboratory Science, Faculty of Allied Health Sciences, University of Africa, Toru-Orua, Bayelsa State, Nigeria

2 Department of Clinical Chemistry, Faculty of Medical Laboratory Science, Rivers State University, Port Harcourt, Nigeria

https://doi.org/10.22038/apjmt.2026.92382.1544
Abstract
Background: The widespread use of plastics has led to an increased environmental presence of microplastics, with potential adverse effects. This study was conducted to assess the effects of polyethylene terephthalate (PET) microplastics on reproductive hormones and Interleukin-1β in chronically-exposed female albino rats.
Methods: Forty female albino rats were selected for the study. Polyethylene terephthalate pellets were obtained, crushed, dissolved in water, and passed through a 5µm sieve to obtain particles with a size of ≤ 5µm which were used for the study.  Twelve rats were used for a pilot study, while the remaining twenty-eight rats were randomly assigned into four experimental groups (n = 7). The PET treatment was administered orally using gavage tubes for 90-days. 40mg/kg, 80mg/kg, and 120mg/kg PET-microplastics were given to rats in groups 2, 3, and 4, respectively, while group 1 received only food and water (negative control). After the duration of treatments, blood samples were collected for analysis of estradiol, progesterone, prolactin, and IL-1β levels using ELISA methods. Statistical analysis was computed using GraphPad Prism Software. Differences were considered significant at P ≤ 0.05. 
Results: The mean levels of estradiol, progesterone, and IL-1β in the PET-treated rats were significantly higher than the levels in the control group (p < 0.0001). However, the mean levels of prolactin in PET-treated groups were not significantly different from those in the control rats (p = 0.2157).
Conclusion: These findings suggest that chronic PET-microplastic exposure may induce inflammatory responses and endocrine disruption in the animal model, as evidenced by alterations in hormone levels and IL-1β concentration, highlighting potential health risks that may be associated with prolonged PET microplastic exposure.

Keywords

Estradiol
Progesterone
Interleukin 1β
Plastic Particles
Toxicity
Subjects
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Asia Pacific Journal of Medical Toxicology
Volume 15, Issue 1
Winter 2026
Pages 21-27

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