Science Snippets: Microplastics Inhibit Marine Absorption of Carbon Dioxide

Draft script:

As I have reported frequently within the last few months, microplastics are posing serious problems for the continued survival of many organisms. Microplastics are tiny fragments of plastic less than five millimeters in size. They contaminate the oceans, lakes, and rivers on Earth. They are found in remote locations, including high mountain peaks and clouds.

From the Oceanic Preservation Society comes yet another article about microplastics. Titled Microplastics: Pervasive Pollution and Their Impact on Human Health, the article was published 4 March 2025. The article begins with a summary of the history of microplastics. As with the rest of the article published by the Oceanic Preservation Society, references to additional research are included: “Microplastics—tiny fragments of plastic less than five millimeters in size, and even smaller nanoplastics—have become a ubiquitous feature of our modern world. Once considered an issue confined to ocean debris, we now know that these particles have infiltrated every corner of the environment and even our own bodies. In this post, we’ll explore where microplastics have been found—from water and air to remote mountain peaks—and examine the emerging evidence of their presence in human tissues, as well as the potential negative health effects.”

This opening paragraph is followed by a subsection titled Microplastics in the Environment. This subsection is divided into two additional sub-subsections. The first is titled “Water, Air, and Beyond.” It contains two horrifying paragraphs that cite additional literature: “Microplastics have been detected in virtually every environmental matrix. They contaminate our oceans, rivers, and lakes, where they enter the food chain through marine life and freshwater organisms. Studies have documented their presence in drinking water and even in rain and snow—demonstrating that no corner of the planet is exempt from plastic pollution. For example, researchers have found microplastics in remote regions like the high peaks of mountains and even in clouds, highlighting the capacity for these particles to be transported by wind over vast distances.

Airborne microplastics, including microscopic fibers shed from synthetic textiles and the breakdown products from car tires and other urban sources, have been detected in both indoor and outdoor environments. A study measuring microfibers in urban dust reported that these plastic particles can accumulate in the air we breathe, potentially traveling from city centers to even the most isolated regions. Additionally, microplastics have been found in soil and agricultural lands, often as a result of contaminated wastewater or atmospheric deposition. Even our food can be a source of microplastic exposure—sea salt, for example, often contains plastic particles derived from ocean pollution.”

The next sub-subsection is titled “The Ubiquity of Microplastics.” It, too, contains links to additional, relevant information. In two short paragraphs, it explains that microplastics are common throughout this planet: “From the convenience of our packaged foods to the cosmetics we apply daily, microplastics are everywhere. Studies have shown that the average person may ingest tens of thousands of microplastic particles each year—not to mention those we inhale in dust and air.

With plastic production continuing to rise exponentially, the problem is only growing more severe. As environmental contamination increases, so does the likelihood that these tiny particles will continue to infiltrate our ecosystems.”

The following subsection is titled “Microplastics in the Human Body.” Under a sub-subsection titled “Evidence of Infiltration,” we find three descriptive paragraphs: “Until recently, scientists believed that microplastics were primarily an environmental issue. However, groundbreaking research has now revealed that these particles are present in human tissues. Microplastics have been detected in human blood, the placenta, and even in our brain tissue. For instance, a study led by Professor Matthew Campen at the University of New Mexico found microplastics in brain, liver, and kidney samples from people who died in different years—with a 50% increase in brain contamination observed over just eight years.

Other research has confirmed the presence of microplastics in human placentas. In one study using Raman microspectroscopy, researchers detected tiny plastic fragments in several placental samples—raising concerns about fetal exposure during a critical period of development.

Similarly, studies have reported microplastics in human blood and even semen, indicating that these particles circulate throughout our bodies and may accumulate in various tissues over time.”

The second and final sub-subsection is titled “A Growing Trend.” It describes the relationship between microplastics in the environment and the potential for human exposure: “The evidence suggests that as the environmental load of microplastics increases, so too does the level of human exposure. Data indicate that microplastic concentrations in human tissues have been rising steadily over the past few decades. For example, newer brain tissue samples show much higher levels of microplastics compared to older samples, a trend that mirrors the ever-increasing production and disposal of plastic products worldwide.

Moreover, some studies have observed that individuals with conditions like dementia may have significantly higher levels of microplastics in their brains, although researchers caution that a direct causal link has yet to be established.”

The next subsection is titled “Health Effects: What Do We Know?” It contains three sub-subsections, the first of which is titled “Potential Mechanisms of Harm.” It contains two paragraphs that bring non-experts up-to-date: “While research into the health impacts of microplastics is still in its early stages, several mechanisms by which these particles might harm the human body have been proposed. Laboratory studies on animals and cell cultures have shown that microplastics can cause inflammation, oxidative stress, and even interfere with cellular function. For example, exposure to microplastics has been linked to the activation of inflammatory pathways and the production of reactive oxygen species—factors that are known to contribute to various chronic conditions.

Furthermore, some microplastics contain chemical additives like phthalates and bisphenol A (BPA) that are known endocrine disruptors. These chemicals can interfere with hormone regulation, potentially affecting reproductive health, growth, and development. Although microplastics themselves are often considered biologically inert, their ability to act as vectors for these harmful chemicals raises additional concerns about their cumulative impact on human health.”

The next sub-subsection is titled “Associations with Disease,” and it addresses associations between microplastic exposure and health issues resulting from epidemiological and experimental studies. These include Neurological Concerns, Cardiovascular and Respiratory Issues, Reproductive Health, and Metabolic and Digestive Disorders.

The final subsection is titled “Conclusion: A Call for Systemic Change.” It explains that we can all take actions to mitigate the issue. Surprisingly, it also points out that “the solution requires systemic change and robust government intervention to truly mitigate the global plastic crisis.” This marks a rare admission: “systemic change and robust government intervention” are required to address this issue. Contrary to the usual pleas for individual action, this article correctly points out that microplastics require efforts beyond the masses.

I now turn briefly to the peer-reviewed, open-access paper in the Journal of Hazardous Materials: Plastics. This paper was written by five scholars and published in February 2026. Titled From pollution to ocean warming: The climate impacts of marine microplastics. It opens with four Highlights that provide a good overview of the disaster underlain by microplastics:

First, “microplastics disrupt nutrient cycling and influence climate-related processes.” Second, “microplastics interact with ocean warming and acidification, amplifying ecological impacts.” Third, “Combined effects of microplastics, warming, and acidification threaten marine ecosystem stability.” Fourth and finally, “microplastic pollution hinders progress toward multiple UN SDG targets.” “UN SDG targets” refers to United Nations Sustainable Development Goals.

Microplastics have become a worldwide disaster in a relatively short period of time. The word microplastic was coined in 2004. In slightly more than two decades, microplastics have become major players in the arenas of science, pollution, and medicine.