The Maldives archipelago in the Indian Ocean includes 1,192 islands. In 1992, the government added one more—an artificial construct that serves as a landfill, where 500 tons of trash are dumped every day.
Two truisms of island-living everywhere are especially true in the Maldives: Most consumer goods must be shipped in, and most waste is produced by tourists. In the Maldives, a developing nation that lacks much local manufacturing, a single tourist produces almost twice as much trash per day as a resident of the capital city of Malé, and five times as much as residents of the other 200 populated islands, according to government statistics. Consequently, the tiny island nation was ranked last year as the world’s fourth largest producer per capita of mismanaged waste.
Now marine scientists at Flinders University, near Adelaide, Australia, have added another, predictable statistic to the Maldives’ trash horror story: The island chain, renowned for its rich marine biodiversity, is also home to the world’s highest levels of microplastics on its beaches and in the waters near shore.
Across 22 sites on Naifaru, the most populous island, the Flinders team counted high concentrations of microplastics in beach sand and shallow coral reef waters. Aside from the sheer volume, the team made an even more discouraging discovery. Most of the particles were the same size as prey consumed by various marine life on the reef.
That was not good news for a tropical marine ecosystem that supports more than 1,100 species of fish and 929 other species, ranging from amphipods to whales, as well as 170 species of sea birds. Of 71 trigger fish collected by the researchers, all had plastic in their bellies, on average eight fibers per fish.
“The size of the microplastics is extremely important because they get into the smallest fish and invertebrates, which are then consumed by larger fish,” says Flinders conservation biologist Karen Burke Da Silva, the senior author of the study.
The findings in the Maldives, published August 2 in the journal Science of the Total Environment, are part of an impressive body of scientific literature published so far this year that adds new understanding of this plastic scourge—and that may aid efforts to combat it. (Read more: We depend on plastic. Now we’re drowning in it.)
The microplastic cycle
“In order to understand how to mitigate plastic pollution, we have to know the flux,” says Chelsea Rochman, a marine ecologist at the University of Toronto. “It’s one thing to know it’s there, and now we need to know the rate at which it gets to places. To hot spots, and what happens to it as it moves through ecosystems.”
While most of the early research focused on the larger plastics found on beaches and floating on the surface, less visible and more pervasive plastic bits have spread into virtually every crevice on Earth, from the deepest sea trenches to the highest alpine mountains. Some microplastics are so tiny they are part of the dust that blows around the planet, high in the atmosphere.
In recent years, scientists have tracked microplastics to thousands of locations. The new research marks a shift toward figuring out what Rochman calls the “microplastic cycle”—how microplastics travel, where they accumulate, and how they are transformed en route.
The term microplastics refers to plastic particles that measure less than five millimeters. There are two basic kinds.
Primary microplastics, such as microbeads used in personal care products or the pellets used in plastics manufacturing, are intentionally manufactured small. Secondary microplastics are the consequence of one of plastic’s most valued assets: its durability. They begin as discarded products that are broken down in the oceans by sunlight and wave action. Over time, the fragments become smaller and smaller. They will presumably survive for centuries.