Beach poison will kill you in an hour

The warning signs will not be removed until investigating agencies believe Auckland's beaches are safe. Photo / Greg Bowker

Experts have added a grim warning to the poison beach scare in Auckland, saying the toxin that killed dogs is deadly enough to paralyse humans in seconds and kill them within an hour.

Test results have shown that tetrodotoxin, a poison found in puffer fish, is responsible for the deaths of two dogs, birds and sealife on Auckland beaches.

The poison was found in the dead dogs' vomit and in a sea slug sample taken from Narrow Neck Beach on the North Shore.

Further tests are being carried out to find out how the sea slug came to contain the poison.

Touching a dead animal on the beach could be enough to endanger human life, said Cawthron Institute algae specialist Paul McNabb.

He said that warnings for people to keep away from beaches were not extreme, because of the effects the toxins had on humans.

"People can die from this," Mr McNabb said.

"If you put a slug in your mouth, you'd be vomiting and your entire body would be tingling.

"Within minutes you'd be paralysed. Your heart and lungs would shut down and you'd be dead within the hour.

"Or if you touched it and it was all over your hands and you went and ate a sandwich ..."

Mr McNabb said anyone who came down with symptoms including vomiting and drowsiness, after being at a beach, should see a doctor.

But the only way a person would die was if they consumed the poison.

Health authorities were alerted to the problem when several dog owners reported their pets getting sick, vomiting and foaming at the mouth, after walking on an Auckland beach.

Warning signs were soon posted at beaches on the North Shore and in Auckland City after more reports of pets becoming sick and birds and fish washing up dead on beaches.

Up to eight agencies - including health authorities and city councils - have been meeting to examine the test results.

Mr McNabb said it was a sad but thankful thing to have been alerted to the problem following the dogs' deaths.

"It's good that it's happened like this," he said.

"It's sad for the dogs and their owners - but it's better to have it happen this way and we find out from the dogs dying and not from people dying."