Pollution / Toxicology
Literally thousands of different man-made pollutants enter our estuaries. These may include nutrients from fertilizers placed on lawns and golf course that cause blooms of harmful algae in detention ponds and estuaries. Pollutants also include compounds such as polycyclic aromatic hydrocarbons (PAH’s; commonly in the form of oil or fuel products), polychlorinated biphenyls (PCBs; a class of cancer-causing industrial chemicals that was banned in the US in the 1970s), pesticides, herbicides, polybrominated diphenyl ethers (PBDEs; fire retardant chemicals found in practically every consumer product) and pharmaceuticals to name just a few. Many of these chemicals can have devastating effects on the environment and have been found to accumulate in benthic sediments and in the tissues of birds, fish and humans where they may have a range of toxicological effects from sickness to death.
ERS staff address the pollution of SC estuaries using several approaches:
- monitoring pollution levels along the SC coastline (SCECAP),
- examining the relationships between estuarine pollution levels and land-use patterns (suburban development, agriculture, high-intensity urban and industrial development, etc),
- developing new tools for evaluating environmental toxicity.
PAH Levels in Salt Marshes
Roadways potentially act as a major source of polycyclic aromatic hydrocarbons that can run off into nearby marsh habitats. In 2005, ERS completed a study on the levels of PAH compounds found in estuarine habitats around the state. This study found that vehicular traffic on SC roads releases PAH’s that can then enter salt marsh, tidal creek and mudflat habitats. This conclusion was supported by two primary findings. First, PAH concentrations were highest closest to the road surface and decreased with increasing distance from the road surface. Second a chemical related to the breakdown of rubber tires was abundant in all of the habitats, indicating that the PAH levels were related to vehicles rather than to atmospheric sources.
Dr. Denise Sanger