Microplastics Lower Testosterone in Multiple Ways

⚕️ MEDICAL DISCLAIMER: This article is for informational and educational purposes only and is not intended as medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider before making any changes to your health regimen, diet, or supplement use, especially if you have existing medical conditions or take medications. The information presented here should not be used to diagnose, treat, cure, or prevent any disease.

Microplastics interfere with testosterone production at multiple points in the process, from the hypothalamus to the testes.

Animal studies consistently show that exposure to polystyrene microplastics, polyethylene, and polyamide leads to sharp drops in serum testosterone levels [1,2,5,7,9,10]. In some cases, these particles directly damaged Leydig cells, the testosterone-producing cells in the testes, while also impairing the body’s ability to regulate steroidogenesis [5,6].

Outside of impacting testosterone levels, microplastic exposure also reduced sperm count, motility, and normal morphology. These declines are markers of deeper endocrine damage that extends beyond testosterone itself [9,11,16].

How Microplastics Lower Testosterone

Microplastics lower testosterone through three key effects. 

1. Disruption of the Hypothalamic-Pituitary-Gonadal (HPG) Axis

This axis controls testosterone synthesis via a hormonal relay system. Firstly, gonadotropin-releasing hormone from the brain stimulates luteinizing hormone from the pituitary, which then activates testosterone production in the testes. Microplastics interrupt this loop by reducing gonadotropin-releasing hormone and luteinizing hormone levels, ultimately lowering testosterone output [1,12].

They also interfere with the LHR/cAMP/PKA/StAR pathway inside Leydig cells, which is a molecular cascade critical for steroid hormone production [8,13,14].

2. Direct Cellular Damage to Leydig Cells

In both in vivo and in vitro studies, microplastics induced mitochondrial dysfunction in Leydig cells, leading to oxidative stress, DNA fragmentation, and cell death [5,23]. This not only reduces testosterone output but limits the body’s ability to regenerate these vital cells over time.

3. Disruption of Testosterone Biosynthesis Enzymes

Key enzymes in the testosterone production pathway, like 3β-HSD, 17β-HSD, and P450scc, are inhibited by microplastic exposure. These enzymes convert cholesterol into testosterone. Without them, hormone synthesis grinds to a halt [6].

Polystyrene nanoplastics also downregulate StAR protein, which is essential for moving cholesterol into the mitochondria, impacting testosterone production [6].

Overall, there are several key ways in which microplastics disrupt testosterone production. 

Inflammation and Oxidative Stress Amplify the Problem

The testes are particularly sensitive to inflammation. Microplastics elevate oxidative stress markers and activate inflammatory signaling molecules like NF-κB, IL-1β, and IL-6 in testicular tissue [3,6,10,16,21]. These cytokines impair sperm development and testosterone production while accelerating cellular aging.

Long-term exposure triggers sustained immune responses that increase fibrosis and impair reproductive capacity [3,6,9,10]. 

Microplastics May Cause The Blood-Testis Barrier To Break Down

The blood-testis barrier protects developing sperm from immune attack and toxins. But microplastics compromise this barrier, making the testicular environment more hostile and allowing further infiltration of harmful substances [3,6,9,10,15,22].

Once the blood-testis barrier is breached, testosterone production declines sharply and spermatogenesis stalls.

Even Testosterone Itself Can Be Hijacked By Microplastics

Some microplastics, especially polyamide (PA) particles, can adsorb free testosterone, physically binding to it and reducing its availability in the body [9]. This not only diminishes circulating hormone levels, but may prevent testosterone from reaching androgen receptors inside target cells.

This results in less testosterone signaling, even if the hormone is still being produced.

Yes, Human Studies Show It Too

Microplastics have been detected in human semen, testes, and even female reproductive organs [3,6,16,17]. Though human data is still limited, correlations are growing between microplastic exposure and declines in sperm concentration, testosterone levels, and fertility [3,15].

In fact, some researchers believe the global decline in sperm counts over the past five decades may be partially explained by the rise of environmental pollutants like microplastics [3].

The Type of Microplastic Influences The Impact To Testosterone

Different microplastic particles have been shown to impact testosterone differently. For example, polystyrene is strongly linked to reduced testosterone and testicular inflammation [2,4,5,6,7,9,10,13,14,15,20,24,25]. Polyethylene has been associated with oxidative damage, hormonal disruption, and testicular aging [1,14,21,26]. Polyvinyl chloride has been detected in human reproductive tissues as well, although its exact effects are still being studied [16,27]. Lastly, polyamide has been known to absorb testosterone directly, reducing its bioavailability [9]. 

Can Anything Help To Reduce The Impact of Microplastics On Testosterone? 

A few studies have tested antioxidant therapies with promising results. Compounds like fucoidan, melatonin, kaempferide, and naringin have been shown to mitigate microplastic-induced reproductive toxicity by reducing oxidative stress and stabilizing hormone levels [19,21,24,26]. Of course, much more research is needed to understand the full effect of these compounds. 

How Can I Avoid Microplastics?

There’s more and more evidence that shows that microplastics can knock our hormones out of balance. For individuals concerned about their health, developing a strategy to reduce microplastics intake is critical to promote properly functioning hormones. 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 science-backed supplement, a microplastic intake tracking app, and lifestyle recommendations is intended to help you avoid microplastics. Our supplement 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. 

Sources

1. A review of the neurobehavioural, physiological, and reproductive toxicity of microplastics in fishes
2. A systematic review of microplastics emissions in kitchens – Understanding the links with diseases in daily life
3. Association of mixed exposure to microplastics with sperm dysfunction – a multi-site study in China
4. Can Mammalian Reproductive Health Withstand Massive Exposure to Polystyrene Micro- and Nanoplastic Derivatives – A Systematic Review
5. Chronic Polystyrene Microplastic Exposure Reduces Testosterone Levels in Mice through Mitochondrial Oxidative Stress and BAX_BCL2-Mediated Apoptosis
6. Combined effects of polystyrene nanoplastics and lipopolysaccharide on testosterone biosynthesis and inflammation in mouse testis
7. Detection of microplastics in human tissues and organs – A scoping review
8. Detrimental consequences of micropolymers associated plasticizers on endocrinal disruption
9. Effects of the adsorption behavior of polyamide microplastics on male reproductive health by reduction of testosterone bioavailability
10. Health Implications of Widespread Micro- and Nanoplastic Exposure – Environmental Prevalence, Mechanisms, and Biological Impact on Humans
11. Human Exposure to Microplastics and Its Associated Health Risks
12. Impact of polyethylene microplastics exposure on kallikrein-3 levels, steroidal-thyroidal hormones, and antioxidant status in murine model – protective potentials of naringin
13. Micro(nano)plastic and Related Chemicals – Emerging Contaminants in Environment, Food and Health Impacts
14. Microplastic exposure is associated with male reproductive health
15. Microplastics exposure – implications for human fertility, pregnancy and child health
16. Effects of Polyvinyl Chloride Microplastics on the Reproductive System, Intestinal Structure, and Microflora in Male and Female Mice
17. Microplastics detected in three types of female reproductive organs using micro-Raman spectroscopy
18. Effects of micro(nano)plastics on the reproductive system – A review
19. Melatonin counteracts polyethylene microplastics induced adreno-cortical damage in male albino rats
20. Long-term exposure to polystyrene microplastics triggers premature testicular aging
21. Mitigative potential of kaempferide against polyethylene microplastics induced testicular damage by activating Nrf-2/Keap-1 pathway
22. Examining the Relationship Between Polystyrene Microplastics and Male Fertility – Insights From an In Vivo Study and In Vitro Sertoli Cell Culture
23. Exposure to nanoplastics induces mitochondrial impairment and cytomembrane destruction in Leydig cells
24. Fucoidan from Cladosiphon okamuranus enhances antioxidant activity and prevents reproductive dysfunction in polystyrene microplastic-induced male rats
25. Gut microbiota combined with metabolome dissects long-term nanoplastics exposure-induced disturbed spermatogenesis
26. Microplastics in the Human Body – Exposure, Detection, and Risk of Carcinogenesis – A State-of-the-Art Review
27. Impact of Microplastics and Nanoplastics on Human Health