The Green Party is criticising the possible use of methyl bromide at the Port of Tauranga, despite the Environmental Protection Agency allowing its use until 2021.
Methyl bromide is used routinely at the port to fumigate logs before they are exported to China and India, with the EPA approving it for release into the air.
At a public meeting at the Welcome Bay Community Centre last week, Green MP Steffan Browning argued the fact the agrichemical was legal to use did not mean it was safe.
"We must fumigate logs, and although use of methyl bromide is banned in most western countries, its use here is likely to continue for the foreseeable future," Mr Browning said.
"However, current procedures involving direct release to air represent significant risk to local communities.
"Better containment, full recapture and greater isolation of the fumigation facility are all options that need to be explored urgently in Tauranga."
Port of Tauranga chief executive Mark Cairns said the consent for the application of the agrichemical on port land was held by Genera.
He was not sure how much was used at the port annually but noted the port company was supporting efforts to find alternatives.
"We are working with exporters and are funding a group that is looking at alternatives like phosphine for below deck cargo and other solutions, but that's a matter for the industry, not the port," Mr Cairns said.
"It is something that is top of mind for them because the legal requirement is for its use to be phased out by 2020."
Mr Cairns said ports in Wellington and Nelson were able to use alternatives to methyl bromide because of their size.
"They don't have the same volumes for starters. They are both small ports in terms of log exports. We have a much greater forestry catchment; we will likely do six times the volume at least, probably more."
Regional council candidate and former Green Party Tauranga spokesman Ian McLeanit said it was assumed, not known, that dilution of the gas by wind and air was sufficient to render it harmless.
Bay of Plenty Regional Council chairman John Cronin was aware of the use of the agrichemical at the port but said it would be inappropriate for him to comment without first looking into the issue.
In 2007, Professor Ian Shaw of Canterbury University stated the death rate of Port Nelson workers from motor neuron disease appeared to exceed the international average and reported that methyl bromide could have been a factor.
A second report, by Nelson-Marlborough medical officer of health Dr Ed Kiddle, concluded the six cases near the port were probably due to chance, but recommended that methyl bromide be treated with caution and investigated further.
Full recapture of the agrichemical is now required on the site and its use has essentially ceased.
Ports in Picton and Wellington had also dramatically reduced its use, with Wellington requiring full recapture by the end of the year.
Full recovery of gas is not required in Tauranga until 2020.