Contaminants Assessment in the Coral Reefs of the Virgin Islands National Park and Virgin Islands Coral Reef National Monument

Science Center Objects

USGS collected samples at reef locations within the Virgina Islands National Park and analyzed for the presence of contaminants, organotin compounds, or sunscreen compounds.

Trunk Bay, US Virgin Islands

Trunk Bay, U.S. Virgin Islands (Public domain)

The Science Issue and Relevance:  A large and growing body of literature has documented declines in living coral and presented potential factors that may be driving the changes on Caribbean coral reefs. A much publicized stressor of corals in the Caribbean was the increased sea surface temperature event in 2005 that led to widespread coral bleaching. This event was followed months later by coral disease and, in some cases, mortality.  Coral reefs around the world are also exposed to a variety of environmental contaminants, some of which are proven endocrine disruptors, immunosuppressors, and/or toxins that can stress corals and other reef organisms. Until recently, the impact of environmental contaminants on reefs around the U.S. Virgin Islands had received relatively little attention. The USGS has been conducting projects to learn more about potential contamination in Virgin Islands National Park (VIIS) and Virgin Islands Coral Reef National Monument (VICR).

 

Detritus sampling

Detritus sampling from coral reef (Public domain.)

 

 

Methodology for Addressing the Issue:  Multiple components contribute to the overall assessment of contaminants in VIIS and VICR. Firstsamples collected from five different matrices (living coral tissue, fish, plankton, detritus, and water) at four different reef locations within the VIIS and VICR were analyzed for the presence of contaminants.  Then, sediment samples collected from one bay within the VICR were analyzed for organotin compounds (compounds with at least one covalent SN-C bond), which were commonly used in anti-fouling paints on boats.  The third project focused on two aspects of water quality: nutrient enrichment in bays of the VIIS and the presence of sunscreen compounds (e.g., benzophenone-3) in VIIS waters.

Montastrea annularis

Montastrea annularis (Public domain.)

 

 

 

 

Future Steps:  Upcoming studies evaluating benzophenone-3 contamination in coastal waters and genetic signaling in fish chronically exposed to environmentally relevant sunscreen concentrations will enable VIIS personnel to understand the likelihood that sunscreen chemicals from beaches affect nearby coral reefs.