Authorities have cordoned off part of a beach on Queensland's Gold Coast after a canister washed ashore this morning.
Police were alerted to the suspect item at Broadbeach after 8:00am (AEST).
They say the Queensland Fire and Rescue Service is monitoring the situation.
A number of canisters, thought to contain aluminium phosphide, have been washed onto Queensland shores in recent months.
Aluminium phosphide can be fatal if inhaled or ingested, while mild exposure can cause nausea, ringing in the ears, fatigue and pressure in the chest.
Authorities say people should not not open or move any of these canisters and call police.