Government fish ponds in Kiribati were closed down temporarily following the mysterious deaths of several ducks on Monday.
The Ministry of Fisheries has warned the public to stay away from the ponds as investigations will be carried out soon.
Health authorities have confirmed they've taken blood samples from the ducks before they were burnt and disposed of.
Kiribati's former director of health, Dr Airam Metai, says they found a high proportion of chemicals in the ponds which might have happened if people accidentally dropped them in the ponds.
The blood samples will be sent to Australia for further tests.
Dr Metai says the incident has no connection to bird flu.
Members of the public were warned to not eat ducks which they recently brought from the ponds.