WILLEMSTAD – A scientific investigation of Curaçao’s coastal waters has found evidence connecting specific categories of chemical pollution to tourism, urban development, wastewater and other human activities, including elevated levels of certain substances around heavily visited coastal areas.
The research examined 1,394 land-based xenobiotics detected in Curaçao’s nearshore waters and analyzed how different categories of substances were distributed around the island.
While rainfall and ocean currents were the most important overall factors, researchers found that some types of contaminants showed clearer connections with human activity.
One notable example involved substances categorized as drugs of abuse.
Researchers reported elevated levels around tourist hotspots, including the Mambo Beach area, suggesting that tourism intensity and runoff may play a role in their presence. Statistical analysis found that the distribution of drugs of abuse was particularly influenced by distance from runoff channels and population density.
The study also found that plastic additives, surfactants and other compounds associated with domestic use tended to cluster around urbanized parts of Curaçao.
Human metabolites were found near both Willemstad and Westpunt. In Willemstad, their presence was linked to relatively high urban inputs and wastewater discharge.
Piscadera and nearby areas also drew the attention of the researchers.
The study states that elevated concentrations of certain compounds near Piscadera were likely influenced by effluent from the Klein Hofje wastewater treatment plant.
However, the scientists caution against interpreting the results as a simple map showing where pollution originates.
The study demonstrates that ocean currents can transport substances considerable distances after they enter the marine environment. A chemical detected near a particular beach or reef therefore does not necessarily mean that the pollution originated at that location.
This was particularly evident with plant protection products. These compounds were found across the island, indicating that hydrodynamic transport can distribute them well beyond areas where agricultural activity occurs.
The same combination of human activity and ocean circulation helps explain why contaminants originating near densely populated areas can ultimately accumulate along less developed parts of Curaçao’s coastline.
Researchers say the situation became particularly pronounced during the wet season of 2022, when three conditions occurred simultaneously: exceptionally heavy rainfall, reduced current velocities and changes in current direction.
Together, those conditions likely caused the sharp increase in xenobiotic concentrations observed around the coast.
The findings have implications for how Curaçao monitors marine pollution.
Traditional approaches that focus primarily on nutrients or a limited number of known contaminants may miss a much larger mixture of chemicals entering coastal ecosystems. The study notes that xenobiotics can affect marine organisms through growth, reproduction and early development, while exposure to mixtures can produce more complicated effects than exposure to individual substances.
The researchers conclude that pollution management should therefore look beyond individual discharge points. Rainfall, wastewater systems, runoff, tourism and urban activity all contribute to what enters the sea, while Curaçao’s currents determine where those substances eventually travel and accumulate.
The study ultimately describes chemical contamination as an island-wide issue, with pollutants dispersed far beyond their original sources and potentially exposing coral reefs to complex and constantly changing chemical mixtures.