The Department of Environment and Conservation is inspecting 102 Magellan Metals containers used to transport lead carbonate through the port of Fremantle.
Environment minister Bill Marmion said the department's pollution response unit was inspecting the containers, which are awaiting shipping.
"All ground-level containers are being swabbed, with samples being sent to the Chemistry Centre for further analysis," Mr Marmion said.
"The 102 containers have been sealed by an authorised customs agent and the Government is eager to see them safely exported from Fremantle as soon as possible."
"The containers will not be moved until test results come in."
The minister also released a report into tests conducted yesterday at a nearby site at Fremantle Port where other Magellan Metals containers had been stored before shipment to assess any potential lead contamination.
"Readings taken from the site yesterday showed no elevated lead levels," Mr Marmion said.
"The measured lead levels were less than 21 per cent of the residential area trigger level for investigation into lead contamination (300mg/kg) and were no higher than readings taken from a background area.
"One soil sample was taken from a drainage area and is being sent to a laboratory for analysis. If any elevated lead levels are detected, an isotopic analysis will be carried out to 'fingerprint' the lead to determine if it is from Magellan's mine.
"I wish to reassure the community that the most stringent measures were in place to deal with the containers of Magellan lead which were in transit at the time of the stop order."
The Minister added that so far, the Magellan lead that has been detected outside of the 'bulka' bags has been confined within the containers and there is no danger to the community.
Magellan's lead shipments were halted over the weekend after the company reported finding traces of lead outside the double-lined bags in which the substance is transported in.
