Auckland health officials believe they were justified in warning people to avoid many of Auckland's beaches for so long.
Five dogs have died and many more became sick on beaches around the Hauraki Gulf, with scientists blaming tetrodotoxin - a poison found in seaslugs.
The Auckland Regional Public Health Service's clinical director, Dr Julia Peters, insists it was appropriate to wait until Friday to tell people they could safely return to the beaches - though caution is still advised.
Because the service had limited information, Dr Peters says, a comprehensive warning was appropriate.
The situation remains unresolved, she says, because the health authorities still don't know whether the toxin will continue to be found in marine life on the beaches or whether the situation is transitory; and it's unlikely they'll get any new scientific information to help solve the problem for some time.
Children and pets should be closely supervised at all times and should not be allowed to eat anything they find on beaches, she says.
People are also warned not to collect shellfish from the beaches, nor to touch sea slugs.