XN000022-1986-05-27 — Page 4

TUESDAY, MAY 27, 1986

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EVIDENCE INCONCLUSIVE IN FOOD POISONING CASE

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AFTER A THOROUGH INVESTIGATION INTO THE RECENT CASE OF FOOD POISONING AFFECTING 36 SCHOOL TEACHERS IN TUEN MUN, THE GOVERNMENT ANNOUNCED TODAY (TUESDAY) THE EVIDENCE THAT THE TEACHERS WERE POISONED BY FAN MUSSELS CONTAMINATED BY RED TIDE WAS INCONCLUSIVE.

+ IT IS VERY DIFFICULT TO PINPOINT THE CAUSE OF CONTAMINATION, SAID THE MEDICAL AND HEALTH DEPARTMENT'S PRINCIPAL MEDICAL AND HEALTH OFFICER (OCCUPATIONAL AND ENVIRONMENTAL HEALTH), DR S.Y. CHAN, *BUT IT IS SUSPECTED TO BE SOME FORM OF NEURO-TOXIN WHICH HAS NOT BEEN IDENTIFIED IN THIS AREA BEFORE.+

HE ADDED THAT IN THIS CASE MANY THEORIES HAD BEEN DISCUSSED BY SCIENTISTS, BUT ALL EVIDENCE WAS CIRCUMSTANTIAL AND NO CONCLUSIONS COULD BE MADE.

IN THE EVENT OF A SUSPECTED TOXIC RED TIDE OUTBREAK, AGRICULTURE AND FISHERIES DEPARTMENT SCIENTISTS CAN CONFIRM WHETHER RED TIDE IS CAUSED BY A TOXIC SPECIES WITHIN A SHORT TIME OF ARRIVING AT THE SCENE.

ONCE THE CONFIRMATION IS MADE THE URBAN SERVICES DEPARTMENT, THE REGIONAL SERVICES DEPARTMENT AND THE MUNICIPAL SERVICES BRANCH ARE INFORMED AND WARNINGS ARE IMMEDIATELY GIVEN TO SELLERS TO PROHIBIT THE SALE OF SEAFOOD ORIGINATING FROM THE AFFECTED RED TIDE AREA. PENALTIES MAY BE IMPOSED ON SELLERS WHO DO NOT HEED THE WARNING,

HOWEVER, TO ASSIST THE GOVERNMENT IN MAINTAINING ITS VIGILANCE ON RED TIDE, THE PUBLIC IS ASKED TO REPORT ANY SIGHTING OF THE_TIDE IMMEDIATELY TO THE AGRICULTURE AND FISHERIES DEPARTMENT, RED TIDE SIGHTINGS ON BEACHES SHOULD BE REPORTED TO THE URBAN SERVICES DEPARTMENT OR THE REGIONAL SERVICES DEPARTMENT,

FROM JANUARY 1 TO MARCH 31 THIS YEAR, THERE WERE TEN REPORTED CASES OF RED TIDE IN HONG KONG WATERS. BUT NONE OF THESE WAS TOXIC. IN FACT, THE AGRICULTURE AND FISHERIES DEPARTMENT HAS NOT OBSERVED A RED TIDE INVOLVING A SPECIES KNOWN TO CAUSE PARALYTIC SHELLFISH POISONING FOR THE PAST TWO YEARS.

ALSO MAINTAINING VIGILANCE OVER RED TIDE IS THE ENVIRONMENTAL PROTECTION DEPARTMENT WHICH IS CONDUCTING IN-DEPTH STUDIES INTO ITS CAUSES. IN ADDITION, REGULAR SHELLFISH SAMPLES IN TOLO HARBOUR ARE TAKEN BY THE ZOOLOGY DEPARTMENT OF THE UNIVERSITY OF HONG KONG FOR TOXICITY TESTS ON BEHALF OF THE GOVERNMENT.

THE MUNICIPAL SERVICES BRANCH HAS ALSO WARNED SWIMMERS TO BE CAREFUL OF RED TIDES AT BEACHES. A TOXIC RED TIDE CAN CAUSE SEVERE SKIN IRRITATION.

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