Microplastics aren’t just non-reactive, boring plastic fragments. Studies have shown that they have the ability to disrupt our endocrine system. Microplastic particles and their chemical additives can interfere with hormone production, transport, receptor signaling, and metabolism. This can cause numerous disruptions across every major hormonal pathway, including fertility, metabolism, stress regulation, and more. This article provides a high-level overview of how microplastics interfere with hormones. 

How Microplastics Impact Hormones – Mimicry and Receptor Blocking

Microplastics and their leachates, including phthalates and BPA, act as endocrine-disrupting chemicals (EDCs). Many of these compounds can bind to estrogen or androgen receptors, mimicking or blocking the body’s own hormones [2, 4]. This causes the body to misinterpret the levels of hormones in the body and disrupts receptor signaling, feedback loops, and gene transcription controlled by these pathways [3, 6].

Disruption of the Hypothalamic-Pituitary Axes Via Microplastics

Microplastics impair the hypothalamus and pituitary glands, which regulate hormone production. Studies have shown that microplastic exposure reduces prolactin and thyroid-stimulating hormone (TSH) levels, while disrupting key neuroendocrine pathways like GnRH and CRH signaling [7]. These disruptions impact hormone pathways that regulate reproductive, metabolic, and stress. 

Steroidogenesis Interference Via Microplastics

Microplastics reduce steroid hormone output by downregulating key genes like StAR, CYP11A1, and 3β-HSD, which are central to steroid biosynthesis [8, 11]. This lowers circulating testosterone, estrogen, and progesterone levels [3, 4, 9–10]. Male models show reduced testosterone via mitochondrial oxidative damage and apoptosis induction [9]. In females, estrogen and progesterone synthesis falters due to impaired ovarian signaling and mRNA suppression [7, 10]. 

HPG Axis Dysfunction Because of Microplastids

Microplastics interfere with the hypothalamic–pituitary–gonadal (HPG) axis. This includes disruption of gonadotropins like LH and FSH, as well as their receptors on gonadal cells [4, 7, 11]. Plastic additives like phthalates alter GnRH release by binding to GPCRs on pituitary cells and impair LH/FSH signaling in Leydig and granulosa cells [7].

Microplastic Disruption of Thyroid and Adrenal Hormones

Microplastics and plasticizers disrupt the hypothalamic-pituitary-thyroid (HPT) axis, reducing thyroid hormone synthesis and impairing T3/T4 signaling [5, 7]. They also impair the hypothalamic-pituitary-adrenal (HPA) axis, lowering cortisol and altering ACTH levels [7, 11]. BPA exposure increases adrenal gland mass and corticosterone output in animal models [7].

Oxidative Stress and Inflammatory Interference

At the cellular level, microplastics trigger oxidative stress and inflammation in endocrine tissues. This impairs hormone biosynthesis and receptor signaling. In male models, microplastics downregulate the LH-LHR/cAMP/PKA/StAR pathway, collapsing testosterone output [7]. Microplastics also boost glucocorticoid release by disrupting redox and HPA balance [7].

Additive-Driven Toxicity

Plastic additives like BPA, DEHP, and other phthalates leach from microplastics and amplify their endocrine toxicity [3, 8]. These additives can induce adverse effects at low doses and alter gene expression in hormone-sensitive tissues [3]. Even microplastics particles considered chemically “neutral” become endocrine active due to the chemicals that they bind to. 

Microbiome-Hormone Crosstalk

Microplastics affect the gut microbiome, which plays a direct role in hormone regulation via estrogen recycling and peptide secretion [15]. Disrupted microbiota alters enteroendocrine function, creating knock-on effects in systemic hormone levels.

Multi-Axis Systemic Impact

Microplastics can simultaneously impair the HPGL axis (hypothalamic-pituitary-gonad-liver), skewing metabolic and reproductive signaling. These effects vary by sex, exposure window, and polymer type [14]. For instance, polystyrene nanoplastics enhance estrogenic effects in combination with other EDCs, leading to synergistic toxicity [13–14]. 

How To Avoid Microplastics

Studies have shown that microplastics disrupt numerous hormone pathways. While more research is needed to better understand the long-term impacts, scientists have clearly demonstrated that microplastics and the hormone-disrupting chemicals that they carry impact our normal biological processes. Therefore, if you recognize the harms caused by microplastics, it’s critical that you develop a lifestyle strategy aimed at reducing your microplastic exposure and intake. 

While it’s extremely difficult, if not impossible, to avoid microplastics, there are many small, simple actions that you can take each day to lower the amount of microplastics you consume. This is why we developed the Deplasto platform. 

Our platform, consisting of a nutritional supplement, an app for tracking and measuring microplastic intake over time, and lifestyle recommendations is intended to help you avoid microplastics. Our wellness supplement, that contains ingredients that were studied alongside microplastics, is formulated to support your body’s natural detoxification defenses, including oxidative stress management, cellular repair, and antioxidant support. Our microplastic intake app is designed to show you an estimate of your daily exposure, with every datapoint backed by scientific studies, to help you understand how you can best avoid microplastics. Lastly, given that it’s nearly impossible to completely avoid microplastic exposure, we have a plethora of lifestyle recommendations designed to help you make small changes for big impacts. 

Overall, we believe that the best way to eliminate microplastics begins with you and the changes you make to your daily life. Over time, collectively, we can make a significant difference in your health and the environment.

Sources

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4. Health Effects of Microplastic Exposures- Current Issues and Perspectives in South Korea
5. Impact of polyethylene microplastics exposure on kallikrein-3 levels, steroidal-thyroidal hormones, and antioxidant status in murine model- protective potentials of naringin
6. Microplastics- the hidden danger
7. Microplastics may induce food dilution and endocrine disrupting effects in fathead minnows (Pimephales promelas), and decrease offspring quality
8. Detrimental consequences of micropolymers associated plasticizers on endocrinal disruption
9. Effects of polystyrene micro- and nanoplastics on androgen- and estrogen receptor activity and steroidogenesis in vitro
10. Chronic Polystyrene Microplastic Exposure Reduces Testosterone Levels in Mice through Mitochondrial Oxidative Stress and BAX_BCL2-Mediated Apoptosis
11. Effects of Polyvinyl Chloride (PVC) Microplastic Particles on Gut Microbiota Composition and Health Status in Rabbit Livestock
12. Melatonin counteracts polyethylene microplastics induced adreno-cortical damage in male albino rats
13. Effects of microplastics, pesticides and nano-materials on fish health, oxidative stress and antioxidant defense mechanism
14. Behavioral Studies of Zebrafish Reveal a New Perspective on the Reproductive Toxicity of Micro- and Nanoplastics
15. Combined Effects of Polystyrene Nanosphere and Homosolate Exposures on Estrogenic End Points in MCF-7 Cells and Zebrafish
16. A critical review of microplastics toxicity and potential adverse outcome pathway in human gastrointestinal tract following oral exposure