New Research Uncovers Health Risks of Single-Use Plastic Water Bottles
Using single-use plastic water bottles regularly can lead to the introduction of tens of thousands of microplastic and nanoplastic particles into the human body annually.
On the Phi Phi islands in Thailand, amidst the stunning tropical scenery, Sarah Sajedi experienced a pivotal moment that shifted her path from a business career to academia. “I was gazing at the beautiful Andaman Sea, but underneath me was just a disturbing sight—pieces of plastic, especially water bottles,” she recalls. This encounter reignited her passion for reducing waste, leading her to realize that the bigger issue lay in how we consume.
Sajedi, a Concordia University alum, decided to pursue a PhD focused on plastic waste. As a co-founder of ERA Environmental Management Solutions, she brought years of expertise to her research endeavors. Her recent paper, featured in the Journal of Hazardous Materials, investigates the health hazards associated with single-use plastic water bottles, which she describes as both serious and understudied.
The Invisible Threat
In analyzing over 140 scientific studies, Sajedi estimates that individuals ingest between 39,000 to 52,000 microplastic particles annually. For those who consume bottled water, that figure can increase to about 90,000 extra particles compared to those who mainly drink tap water. The plastic particles are so small that they can’t be seen by the naked eye; microplastics range from one micron to five millimeters, while nanoplastics are smaller than a micron.
These particles are released throughout the lifecycle of plastic bottles—from manufacturing and storage to transportation and eventual degradation. Since many bottles are made with low-quality plastic, they tend to shed particles during handling, especially when exposed to sunlight and fluctuating temperatures. Unlike plastics that enter the human body through the food chain, these are consumed directly from the source.
Sajedi highlights the significant health risks associated with plastic ingestion. Once these particles enter the body, they can pass through biological barriers and reach the bloodstream, affecting major organs. Potential consequences include chronic inflammation, hormone disruption, reproductive problems, and even some cancers. However, much about their long-term effects remains unclear, partly due to limited testing and standardized measurement methods.
She discusses various detection methods for nano- and microplastics, noting that while some can pinpoint minuscule particles, they may not identify their chemical composition. Conversely, others can determine material types but might miss the smallest plastics. Many of the most advanced and reliable technologies come with high costs, making them less accessible.
Focus on Education
Sajedi is optimistic about legislative efforts across the globe to curtail plastic waste. Nonetheless, she observes that most regulations tend to focus on single-use bags, straws, and packaging, while the issue of water bottles largely remains unaddressed. “Education is crucial,” she argues. “Plastic bottles are fine in emergencies, but using them daily isn’t advisable. It’s essential to grasp that the risks are rooted in chronic issues, not acute toxicity.”
Reference: “Unveiling the hidden chronic health risks of nano- and microplastics in single-use plastic water bottles: A review” by Sarah Sajedi, Chunjiang An, and Zhi Chen, 14 June 2025, Journal of Hazardous Materials.
