Researchers of the study, which has recently been accepted for publication by Environmental Health Perspectives, found no correlation between specific human health effects in commercial fishermen and low-level exposure to the dinoflagellate Pfiesteria in areas of the Chesapeake Bay.
After following 88 commercial fishermen over 4 years (1999-2002) and analyzing more than 3,500 samples collected during the study period, researchers found no link between the commercial fishermen's work in any area where Pfiesteria was identified and any specific changes on tests or reported symptoms. Although scientists emphasize that unique, isolated outbreaks of Pfiesteria or unusually toxic strains of the organism could plausibly cause human health effects, commercial fishermen, absent these conditions, do not appear to face significant health risks during routine occupational exposure to waters where Pfiesteria is found.
The study is the first methodical, multi-year attempt to link human health effects to waterways where Pfiesteria has been documented and shed more light on health risks associated with low-level exposure to the micro-organism's strains, which are typically found in estuaries of the U.S. mid-Atlantic region in the summer and fall.
In the summer of 1997, a group of commercial fishermen working on the Pocomoke River off the Chesapeake Bay developed a pattern of deficits in learning and memory after exposure to areas that had been associated with several fish kills, which some scientists say were caused by Pfiesteria outbreaks. Research personnel studying Pfiesteria in the laboratory similarly reported neuropsychological deficits after exposure.
The article can be viewed online at www.ehponline.org/docs/2006/8627/abstract.html.
