• by IPS Correspondents (tunis)
• Wednesday, November 23, 1994
• Inter Press Service

TUNIS, Nov 23 (IPS) - In early October, the beaches around the city of Sfax, 270 kilometres down the coast from Tunis, suddenly and inexplicably became jammed with dying fish.

Around two tonnes of fish died daily on the shores for nearly two weeks before the phenomenon eased -- but not before the rise of widespread concern for the future of the regions' fishing industry and the health of the local populace.

Suspicion has fallen on the phosphate factories of Sfax, Tunisia's most industrialised and most polluted city and whose population already records the highest cancer rates in the country.

But after weeks of study biochemists announced to a sceptical Tunisian public that the cause of the mass fish deaths was not due pollution -- but to a combination of too much sun and killer algae.

Environment minister Mehdi Mlika blamed "exceptionally sunny days" and a lack of rain and wind for unnaturally high rates of growth of a species of light-sensitive, poisonous plankton called 'gymnodiniup', that was killing the fish. But he said the algae as not the cause of any illness among Sfax's citizenry.

"This phenomenon appears most often after a more or less long period of calm and hot weather, in a sheltered environment with little movement," said A. Hanza from the Tunisian National Scientific and Technical Institute of Oceanography and Fishing.

Hanza has found abnormally high concentrations of gymnodiniup in local seawater and is cross-checking the species with Gymnodnium Nagasakian, a well known species of toxic algae found worldwide.

The algae secretes toxic limidic, which soaks through the fish's skin and triggers fatal haemorraging. The dead fish were found with red stains covering the abdomen and the anal fin and often bleeding at the rectum and at the base of the gills.

However experts say the algae is no threat to humans. "So far no epidemic of poisoning has been signalled," concluded a study by the Tunisian Society of Biological Chemistry, delivered up in mid November to a panel of distinguished experts in Sfax.

Officials declare there has not been a single case of food poisoning attributable to fish caught locally and sold in local markets. State radio and local posters now promote 'risk-free fish'. Sfax city officials, fearful for local trade, grill fish in the town square and then eat them up in public meals.

But Sfax citizens remain sceptical -- and fish sales remain low.

© Inter Press Service (2014) — All Rights Reserved. Original source: Inter Press Service

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