July Is a Global Plastic-Free Month – Microplastics, Nanoplastics, Nutrition and Your Microbiome

Episode length note: This is a slightly longer pod than usual, with deep dives into cell biology, gene expression, microplastics and nanoplastics, and what this means for nutrition and microbiomes around the 18:42 mark.

Tiny plastics are reaching our gut microbiome – and July’s the perfect time to talk about it. In this episode, I talk about realistic habits and swaps rather than perfection, and how small changes across many people can shift demand and encourage better production.
Key topics covered 

In the middle section of the episode, we explore:

How DNA, RNA and gene expression work as the information pathway from bases to proteins.
Why nanoplastics are small enough to enter cells and potentially interact with DNA, mitochondria and hormone systems.
How micro- and nanoplastics can reach organs including the gut, liver, lungs, heart, reproductive tissues and possibly the brain.
Emerging evidence that plastics may contribute to oxidative stress, inflammation, endocrine disruption and microbiome dysbiosis across species.
Why most current data comes from high-dose in vitro and animal studies, and why we need better chronic, real-world exposure models.

Supporting research and further reading
These are open-access or accessible papers and articles you can read if you want to dive deeper into microplastics, nanoplastics and health:

Toxicokinetics and how particles move through the body

• Chen C‑Y & Lin Z (2024). Exploring the potential and challenges of developing physiologically-based toxicokinetic models to support human health risk assessment of microplastic and nanoplastic particles. Environment International. https://doi.org/10.1016/j.envint.2024.108617
  
  – Proposes a preliminary toxicokinetic model for micro- and nanoplastics and highlights how polymer type, size, shape and surface chemistry affect where particles go and how long they stay.
  
  
• Jeong J et al. (2024). Integrating aggregate exposure pathway and adverse outcome pathway for micro/nanoplastics: A review on exposure, toxicokinetics, and toxicity studies. Ecotoxicology and Environmental Safety. https://doi.org/10.1016/j.ecoenv.2024.116022
  
  – Reviews exposure routes, movement in the body, and toxicity studies for micro/nanoplastics in humans and wildlife.
  
  

Inhalation and lung effects
Borgatta M & Breider F (2024). Inhalation of Microplastics – A Toxicological Complexity. Toxics. https://doi.org/10.3390/toxics12050358

Food Packaging Forum article: What happens to micro- and nanoplastics in the body?
https://foodpackagingforum.org/news/what-happens-to-micro-and-nanoplastics-in-the-body


Cellular effects and organs

• Braun A & Seitz H (2024). Uptake and Cellular Effects of Polymethylmethacrylate on Human Cell Lines. Microplastics. https://doi.org/10.3390/microplastics3020012
  
  – Explores how a common plastic (PMMA) is taken up by human cells and what it does at a cellular level.

Contact and listener questions

If you have questions, stories or ideas for future episodes, I’d love to hear from you.
You can email me at:

Email: [email protected]

I’m happy to pick up listener questions in later episodes, just like the question from Sally in Stoneleigh about reducing plastic cups.

Thank you so much for listening, especially to this slightly longer episode.If you enjoyed it or learned something new:

• Please like this episode on your podcast app.
• Follow or subscribe to Barks and Biomes so you don’t miss upcoming episodes on plastics, nutrition and microbiomes.
• Share the episode with a friend, colleague or fellow animal science/wildlife lover who might find it useful.

Disclaimer

The information in this episode is based on ongoing studies, emerging research and my own interpretations as an animal science student. I do my best to stay balanced and reflect the current evidence, but the science around microplastics and nanoplastics is still developing.

This podcast is for education and curiosity. It is not medical, nutritional or veterinary advice, and it is not intended to cause worry or anxiety. If you or your animals have health concerns or symptoms, please speak to a qualified health or veterinary professional who can assess your specific situation. I am not affiliated in any way with the organisation.

Thank you for listening.