Shellfish harvesting ban lifted in Maine following domoic acid contamination
Shellfish harvesters have been given the go-ahead by the Maine Department of Marine Resources (DMR) to take to the waters in the northeastern-most U.S. state after more than a month-long hiatus due to an unusual toxic algae bloom.
Shellfish harvesting areas between Penobscot Bay and Machiasport, Maine, were reopened by the DMR on 7 November after being closed since late September, when shellfish samples from Jonesport, Corea and Roque Bluffs tested positive for high levels of domoic acid. Waters farther east, near to Machiasport and Calais, were given the greenlight to reopen on 25 October. Nearly five tons of softshell clams, mussels and quahogs that had been harvested in the area were immediately recalled and destroyed after presence of the biotoxin was detected in September, reported the Portland Press Herald.
The presence of the domoic acid is said to have been produced by a bloom of Pseudo-nitzschia, a plankton that is naturally occurring; this is the first recorded bloom of its kind that has created toxic levels of domoic acid, said Maine’s DMR.
“Department scientists and researchers are still unclear what caused a toxic Pseudo-nitzschia bloom, but have said preliminary results from testing by the Woods Hole Oceanography Institute and Bigelow Laboratory for Ocean Sciences indicate a species of the phytoplankton previously undocumented in the Gulf of Maine could explain the toxicity,” according to the Press Herald.
Shellfish from the affected areas tested for domoic acid at levels of 129 parts per million, said the DMR.