Contaminants

Conservation Issue

A scuba diver uses a jar to scoop up sand from the seafloor.
A diver collects a sediment sample from FGBNMS. Photo: G.P. Schmahl/NOAA

There is increasing concern among natural resource managers regarding ocean contaminants, including ciguatoxin, mercury and other heavy metals, microplastics, and oil and gas–related toxins. Incidents of ciguatoxin poisoning in humans and high concentrations of mercury in finfish tissue raise concerns for those catching and consuming fish in and around Flower Garden Banks National Marine Sanctuary (FGBNMS). Outdated sediment contaminant concentration studies necessitate new research to better understand these threats and establish suitable monitoring protocols. Furthermore, the global rise in microplastics poses a challenge for marine resource managers due to its world-wide distribution, persistence in the water column and other habitats, and growing evidence of impacts on organisms that ingest it.

Description

Monitoring marine ecosystems for contaminants is crucial for safeguarding both environmental and human well-being. Ciguatera fish poisoning, caused by ciguatoxins produced by microalgae, poses a significant risk to consumers of seafood from tropical reefs globally. Studies have found varying levels of ciguatoxin in fish caught in FGBNMS, and although rare, ciguatera cases have been reported following the consumption of fish caught in the sanctuary. Additionally, mercury levels in fish samples, particularly barracuda, have surpassed safe consumption limits based on U.S. Environmental Protection Agency guidelines on a variety of occasions. Heavy metals like mercury accumulate in fish, particularly large predators, persisting in marine environments and impacting marine life. This underscores the importance of systematically assessing and regulating pollution levels to safeguard seafood consumption.

The increasing use of single-use products, inadequate waste management, and poor recycling practices contribute to the accumulation of litter in the sea. Marine debris, including plastics and other solid waste, threatens marine life through ingestion and entanglement, highlighting the need for more effective waste management strategies. Additionally, oil and gas platforms occur throughout the northwestern Gulf of Mexico, some of which are in close proximity to FGBNMS. The potential release of contaminants from platforms or pipelines (particularly oil spills) remains a persistent concern, but is only assessed when incidents are suspected. Monitoring efforts are essential for identifying and addressing threats to marine ecosystems, promoting sustainable practices, and preserving ocean health for current and future generations.

Data and Analysis Needs

  1. Baseline levels and/or ranges of priority contaminants and how these compare to similar habitats and marine protected areas
  2. Monitoring protocols and methods for assessing contaminants over time
  3. Concentrations of contaminants in FGBNMS living resources and sediments and how these change over time
  4. Comparison of contaminant concentrations between shallow and mesophotic depths
  5. The economic impact of contaminants in the sanctuary on industry (fisheries, recreation, etc.)
  6. Spatial distribution of contaminants in the sanctuary and surrounding region
  7. Modeling to explore patterns in contaminants based on distance from known sources and the effects of storms and seasonal events
  8. Microplastic and nanoplastic concentrations in FGBNMS waters and their effects on the health of sanctuary organisms
  9. The relationship between contaminants and indicators of ecosystem stress such as coral disease and bleaching
  10. Robust, long-term monitoring of the prevalence and severity of ciguatera in the sanctuary and how these metrics compare to other locations in the region
  11. Identification of potential risks of future energy development in the Gulf of Mexico (e.g., wind farms, liquefied natural gas transport)

Potential Products

  • List of critical contaminants to monitor, as well as appropriate methodologies, equipment, and funding needs for regular monitoring of these contaminants
  • Plans for partnerships and incentive programs that allow fishers and the energy industry to partner with FGBNMS on ciguatera and heavy metal research
  • A report detailing the economic impact of contaminants on sanctuary use
  • A database identifying baseline levels of microplastics within the FGBNMS food web

Supplementary Information

For more information about this assessment, contact flowergarden@noaa.gov.