A new assessment on Tuesday warns that microplastic pollution is severely disrupting global food production by impairing plants' ability to photosynthesize.  

The analysis estimates that between 4% and 14% of the world’s staple crops—wheat, rice, and maize—are being lost due to these pervasive particles, while the situation is expected to worsen as microplastic contamination continues to rise.  

In 2022, around 700 million people experienced hunger, and researchers project that microplastic pollution could put an additional 400 million at risk of starvation over the next two decades—an alarming threat to global food security.  

While other scientists acknowledged the study’s significance, they emphasized the need for further research to confirm and refine these findings.  

According to the researchers, annual crop losses due to microplastics could rival those caused by climate change in recent decades. With the global population expected to reach 10 billion by 2058, ensuring sustainable food production is already a pressing challenge.  

Microplastics originate from vast amounts of waste dumped into the environment and disrupt plant growth by damaging soil, blocking sunlight, and carrying toxic chemicals. These tiny particles have now infiltrated every corner of the planet, from Mount Everest’s peak to the depths of the ocean.

The researchers, led by Prof Huan Zhong, at Nanjing University in China, said, "Humanity has been striving to increase food production to feed an ever-growing population [but] these ongoing efforts are now being jeopardized by plastic pollution."

"The findings underscore the urgency [of cutting pollution] to safeguard global food supplies in the face of the growing plastic crisis."

Impact of microplastics 

Microplastics have already infiltrated human bodies, entering through food and water consumption. They have been detected in blood, brains, breast milk, placentas, and bone marrow. While their full impact on human health remains unclear, they have been associated with an increased risk of strokes and heart attacks.

Prof Denis Murphy, at the University of South Wales, said, "This analysis is valuable and timely in reminding us of the potential dangers of microplastic pollution and the urgency of addressing the issue, [but] some of the major headline figures require more research before they can be accepted as robust predictions."

The study, published in Proceedings of the National Academy of Sciences, analyzed over 3,000 observations from 157 studies on the effects of microplastics on plants.

Earlier research has shown that microplastics harm plants in several ways. These particles can obstruct sunlight from reaching leaves and degrade soil quality. When absorbed by plants, they can block nutrient and water channels, trigger harmful molecules that damage cells, and release toxic chemicals—ultimately reducing chlorophyll levels, which are essential for photosynthesis.

The researchers estimated that microplastics reduce photosynthesis by approximately 12% in terrestrial plants and 7% in marine algae, which form the foundation of the ocean food web. Using this data, they extrapolated the impact on the growth of wheat, rice, and maize, as well as the production of fish and seafood.

Threat to environment 

Asia experienced the most severe crop losses, with annual reductions in wheat, rice, and maize ranging from 54 million to 177 million tons—accounting for roughly half of global losses. Europe also saw significant declines in wheat production, while maize yields in the United States were heavily affected.

In contrast, South America and Africa cultivate smaller amounts of these crops, but data on microplastic contamination in these regions remains limited.  

In marine environments, where microplastics coat algae, fish and seafood losses were estimated between 1 million and 24 million tons per year—about 7% of total production—depriving tens of millions of people of a key protein source.  

To further assess the impact of microplastics on food production, scientists applied a machine-learning model using current pollution data. The results closely aligned with their initial findings.

"Importantly, these adverse effects are highly likely to extend from food security to planetary health," Zhong and his colleagues said.

Additionally, the reduction in photosynthesis caused by microplastics could decrease the amount of climate-warming CO2 absorbed by vast phytoplankton blooms in the oceans, potentially disrupting other ecosystems.