Canister find closes Gold Coast beach PART of a Gold Coast beach has been cordoned off after a canister believed to contain a highly toxic substance washed ashore. Police acted swiftly to shut down a section of Broadbeach just after 8am (AEST) on Wednesday, after they were alerted about the canister. Queensland Fire and Rescue Service staff are monitoring the situation. It's believed the canister is similar to others found along Queensland's east coast, and in northern NSW, over the past year. They contain a potentially lethal substance called aluminium phosphide, which can kill if inhaled or ingested. Even mild exposure causes nausea, fatigue and pressure in the chest. Authorities have been urging beach-goers to avoid the canisters if they see them, as the gas can self-ignite. Anyone who discovers a canister is being told not to open or even move the item and to call police. In January this year, the Australian Maritime Safety Authority said the canisters had likely been lost from a ship. Aluminium phosphide is often used to fumigate ships.