Industrial Chemicals Pose Major, Overlooked Threat to Ocean Health, New Study Warns

Industrial Chemicals Outpace Pesticides and Pharmaceuticals in Ocean Pollution

For decades, regulators have prioritized monitoring pesticides and pharmaceuticals in ocean ecosystems, assuming these were the primary chemical threats to ecological and human health. However, a new study published in Nature Geoscience reveals that a much larger category of compounds—industrial chemicals embedded in everyday products—has been largely overlooked. These substances are now spreading widely, even appearing in remote locations such as Caribbean coral reefs.

According to the research, these industrial chemicals are biologically active and may interfere with microbial metabolism. The study suggests they could be altering the ocean’s carbon cycle, one of Earth’s most critical biogeochemical processes.

"Beyond the usual [pesticides and pharmaceuticals], what really surprised us was that everyday industrial chemicals are showing up at even higher levels and not just in coastal or polluted areas, but pretty much everywhere."

Study Reanalyzes Decades of Ocean Data to Reveal Hidden Pollution

The study, led by Petras and Jarmo-Charles Kalinski, a postdoctoral fellow at the Rhodes University Biotechnology Innovation Centre, reanalyzed 21 publicly available datasets. These datasets included seawater samples collected over more than a decade across the Pacific, Indian, and North Atlantic Oceans, as well as the Baltic and Caribbean Seas.

All groups of pollutants examined—industrial pollutants, pharmaceuticals, and pesticides—belong to a class called xenobiotics: human-made organic compounds foreign to natural systems. While pesticides and pharmaceuticals were prevalent in coastal samples due to agricultural runoff and wastewater, industrial compounds exhibited a different pattern of distribution.

Key Industrial Chemicals Detected in Ocean Samples

• Polyalkylene glycols: Used in hydraulic fluids
• Phthalates: Found in PVC packaging
• Organophosphate flame retardants: Present in furniture and electronics
• Surfactants: Derived from personal care products

"These are chemicals we use all the time," Petras noted. "So they end up spreading widely."

Mapping the Ocean’s Chemical Landscape

The researchers analyzed more than 2,300 samples from temperate coastal zones, coral reefs, and the open ocean. Their goal was to identify xenobiotics and examine the share of dissolved organic matter (DOM), a pool of carbon-containing molecules dissolved in seawater.

In total, the team identified 248 known xenobiotic molecules. Their work provides the most comprehensive chemical map of anthropogenic organic pollution in the ocean to date. To achieve this, the researchers used nontargeted mass spectrometry paired with scalable computational tools. Unlike conventional targeted analysis, which tests only for predefined hazardous molecules, this open-ended approach can detect thousands of chemicals simultaneously, even at low concentrations.

The team then applied molecular networking, a computational technique that enables the identification of not only known substances but also their "families" or derivatives.

Coral Reefs: Unexpected Hotspots of Industrial Pollution

Petras emphasized the need to rethink the concept of "pristine" environments, noting that anthropogenic pollution sources are now nearly everywhere. He was particularly surprised to find these compounds in coral reefs, such as those in French Polynesia, which are often viewed as untouched paradises.

Yet, closer examination reveals the presence of industrial chemicals in these remote ecosystems, underscoring the pervasive nature of this pollution.