A muscle-destroying disease in people who've eaten Buffalo fish (Ictiobus) or crayfish in the U.S. may be linked to Water hemlock.
Haff disease isn't common, with only 30 reported cases in the U.S. since 1984, although it affected three people in Mississippi last month, all of whom had eaten Buffalo fish. Symptoms usually appear within 12 hours of eating the fish and include chest pains, muscle pain and weakness, nausea, vomiting, dry mouth, and a dark-coloured urine. None of the cases reported in the U.S. have proved fatal.
However, because the chest pains are similar to those of a heart attack, it's possible that some cases are being mis-diagnosed.
According to a report in the Sun Herald, experts believe that the illness could be caused by humans eating bottom-feeders that have been feasting on the tuberous roots of Water hemlock — described as the most toxic plant in North America. The plant is very common and grows in shallow water that can flood for some of the year.
Haff disease is caused by a toxin that destroys skeletal muscle tissue - possibly the same one (cicutoxin) found in Water hemlock and which is particularly concentrated around the roots of the plant.
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