Tiny plastic particles, no wider than a human hair, have made their way into an alarming new corner of human biology: the fluids surrounding eggs in women and sperm in men. The latest research, unveiled at the 2025 European Society of Human Reproduction and Embryology conference and published in the journal Human Reproduction, provides the clearest evidence yet of microplastics’ persistent ability to infiltrate the most sensitive aspects of our bodies—raising serious questions about fertility, long-term health, and the true cost of our reliance on plastics (Earth.com; CNN).
The study—led by a European team—analysed follicular fluid from 29 women and seminal fluid from 22 men. Astonishingly, microplastics were detected in 69% of the women’s samples and 55% of the men’s—a finding described by the researchers as “surprising in its pervasiveness.” The most commonly found plastics were polytetrafluoroethylene (PTFE), polypropylene (PP), and smaller quantities of polystyrene and polyethylene terephthalate (PET)—materials that originally belonged in nonstick cookware, food packaging, and synthetic textiles, but are now turning up next to reproductive cells (Medical Xpress; EurekAlert).
For Thai readers, the implications are immediate and deeply personal. Thailand’s rapid urbanisation, Western-style diets, and reliance on plastics for food and beverage containers echo global trends—and may be placing local fertility at risk. In a country already facing a sharp decline in birth rates and rising concerns about reproductive health, the potential for microplastics to disrupt the very beginnings of life is a wake-up call.
The concern is not only exposure, but the cumulative health burden. Plastics, once primarily an environmental worry, are crossing directly into the realm of fertility and human development. In 2021, researchers in Italy found plastic fragments in every placenta they examined, showing microplastics can cross the maternal-fetal boundary. Other studies have found these particles deep in human lung tissue, indicating inhalation is a likely route (CNN). Dutch scientists recently documented microplastics circulating in human blood, which explains how these fragments migrate to distant tissues—including the most delicate sites required for reproduction.
But how do these plastics reach our reproductive systems? The routes are numerous: eating, drinking, and even breathing, as dust from plastic packaging, bottles, textiles, and utensils becomes ubiquitous in daily life. Once small enough—usually less than five millimetres and sometimes under a micrometre in size—these fragments can cross gut walls or the fine membranes in the lungs and spread throughout the body. In animal studies, fragments this size enter cells directly, causing oxidative stress, inflammation, and tissue damage (Earth.com; The Independent).
The research team behind the current findings took care to collect every sample in glass containers, ensuring laboratory contamination was avoided; the plastics they found are genuinely present in people’s reproductive fluids, not the result of stray lab debris (Earth.com).
Studies on animal models have been particularly worrying. Mice exposed to microplastics shed sperm with damaged DNA that moves sluggishly—a likely result of oxidative damage overwhelming natural defences. Polystyrene fragments caused mouse cells responsible for testosterone (Leydig cells) to develop shriveled mitochondria, leading to lower testosterone and smaller litters. For eggs, exposure hinders proper maturation and may lead to imbalances in the body’s hormonal regulatory circuits (PubMed: Effects of microplastics on female reproductive health).
Humans may not be any safer, although direct evidence of clinical impacts is not yet proven. However, microplastics were found in 31% of sampled human egg fluid and 41% of semen, with polymer types mixing differently between women and men. Sperm appeared to pick up more PTFE and polystyrene, eggs more PP. Small additional numbers of PET were also present (EurekAlert). Since reproductive cells are fragile by design, and their developmental journey lasts many months, even tiny disturbances could potentially have long-term consequences.
Global plastic production has exploded from less than two million tonnes in 1950 to 460 million tonnes in 2019, and every increment means more fragments released into air, water, and the food chain (CNN; Earth.com). For Thailand—one of Southeast Asia’s leading users and producers of single-use plastics—the study’s findings are a crucial reminder of the nation’s vulnerability. Decades of waste mismanagement and limited recycling infrastructure have allowed plastic debris to permeate the Mekong River delta, the Gulf of Thailand, and the capital’s markets, increasing the likelihood of ingestion and inhalation.
Expert opinions reflect both concern and calls for balanced action. A leading reproductive scientist from the University of Lisbon advised: “They should be considered an additional argument in favor of avoiding the generalized use of plastics in our daily lives.” This scientist and others stress the need for further research, especially to prove a direct link between microplastic exposure and infertility, but the mounting evidence in animals and humans makes precaution a wise approach (Earth.com).
Future Thai fertility research will likely build on these groundbreaking data points. Bangkok clinics are expected to join international cohorts examining whether higher microplastic “loads” in reproductive fluids correspond to poorer embryo quality during IVF procedures—crucial data in a country where assisted reproductive technology is growing in popularity (CNN). Planned lifestyle questionnaires will help tease out whether bottled water habits or common plastic food containers correlate with increased risks—a practical step towards linking abstract threats to everyday choices (EurekAlert).
Thailand’s history with plastics is part of a wider global story. The nation’s cultural traditions once relied on banana leaves and earthenware, but these have gradually been replaced by convenient plastics—especially in urban centres and markets. Government campaigns in recent years have encouraged a return to reusable containers and bans on microbeads, but enforcement is uneven and single-use plastic remains stubbornly popular (Bangkok Post).
If current trends persist, researchers warn, the problem will persist or even escalate as climate change creates more flooding and waste dispersal, and plastic production continues to surge. Meanwhile, policymakers at the United Nations are negotiating a global plastic treaty, designed to cap new production and spur better recycling—a rare example of collective governmental urgency in response to evidence of human health impacts (Earth.com).
Dr. Philip Landrigan, a leading global environmental health expert, called the treaty “a once-in-a-generation chance to protect human health because curbing output remains the only sure way to slow microplastic fallout.” He points to preliminary fertility data as a stark signal that action is overdue.
But individuals are not powerless. Experts recommend practical steps: switch from plastic to glass or stainless steel water bottles; replace scratched nonstick pans to limit PTFE exposure; use bamboo or ceramic instead of plastic cutting boards; allow takeaway food to cool before transferring it from foam containers; and deploy HEPA air filters or regular vacuuming to keep plastic fibres out of household air. These actions may not solve the problem entirely, but can reduce both microplastic intake and exposure to the hormone-disrupting chemicals plastics may carry (Earth.com).
For Thai families, this is doubly important: cutting plastic in the kitchen, at the dining table, and in daily routines can help protect vulnerable members, especially pregnant women and young children whose cells and organs are developing most rapidly.
The presence of microplastics is a sobering reminder that the consequences of lifestyle change may be felt for generations. At a time when national conversation is focused on shrinking family sizes, declining fertility, and looming population decline, Thais must weigh the balance between everyday convenience and the unseen risks quietly accumulating in their bodies.
Thailand stands at a crossroads. A return to traditional wisdom—opting for metal tiffin carriers, woven baskets, and clay water jars—along with modern scientific awareness, could offer the best hope for safeguarding the nation’s fertility and future.
To stay informed, Thais should follow updates from trusted health institutions—including the Thai Ministry of Public Health and international bodies like the World Health Organization—and seek professional advice if concerned about fertility. Practical adjustments to diet, packaging choices, and household cleaning may offer protection until policymakers and the global community catch up with the science.
Adapting to this new knowledge is not only about reproductive health, but about taking Thailand’s place as a leader in Southeast Asian public health and environmental sustainability.
Sources: Earth.com, CNN, Medical Xpress, EurekAlert, Bangkok Post, PubMed