UPDATE 6.50PM: A canister found washed up at Noosa North Shore this morning did not contain toxic gas.
A beachgoer raised the alarm about 9am after spotting the canister about one kilometre north of Teewah after the North Shore.
Queensland police cordoned off an exclusion zone at the beach but later determined it was not dangerous.
Yesterday, a canister containing a toxic gas discovered on Mooloolaba beach. The car park on Urunga Esp in Mooloolaba Beach had to be evacuated after the silver canister was found there unattended about 3pm yesterday.
It contained aluminium phosphide, which can be fatal if inhaled or ingested.
It's believed someone found the silver canister on the beach and brought it up to the car park before leaving it there.
An off-duty officer, who was at the beach with his wife and kids, spotted the canister before leaving and called for help.
The canister could have been sitting unattended in the car park for hours.
Duty district officer Ray Hoelscher said it was lucky whoever brought it up from the beach wasn't killed.
"If they had put that in the car with them and driven off they wouldn't have made it home," Senior Sergeant Hoelscher said.
"There's a chance they had kids and could have put it in the car with them."
Snr Sgt Hoelscher was the one to move the canister from the car park into a public bin behind a nearby public toilet block.
Police and firefighters then set up a 25 metre exclusion zone until a Hazchem team from Brisbane could arrive to dispose of it.
Aluminium phosphide is a colourless, flammable and toxic gas. Mild exposure by inhalation causes indefinite feeling of sickness, ringing in the ears, fatigue, nausea and pressure in the chest which is relieved by getting away from the gas and getting fresh air.
The chemical, when exposed to air or moisture, can generate the highly toxic phosphine gas that could also self ignite in the right conditions.