New phosphine rules could disrupt Australia’s grain exports

Australia’s grain industry is warning that planned changes to workplace phosphine exposure limits could significantly disrupt grain logistics and exports. Safe Work Australia plans to reduce the allowable workplace phosphine concentration from 0.3 ppm to 0.05 ppm by December 1, 2026—a sixfold reduction. Grain Trade Australia argues that the industry is not yet capable of reliably monitoring such ultra-low concentrations.

Phosphine remains the primary and most cost-effective fumigant used to eliminate insect pests in grain before storage and export. After fumigation, silos, railcars, and ship holds must be ventilated until gas concentrations fall to safe levels. Under the proposed standard, this process could take considerably longer, delaying grain handling operations and port logistics.

According to the industry, the biggest challenge is the lack of equipment capable of accurately measuring phosphine at 0.05 ppm under field conditions. Most commercially available portable gas detectors operate at the limit of their sensitivity, meaning that inaccurate readings or false alarms could halt operations at grain elevators, rail terminals, and ports. This could result in vessel delays, port congestion, and substantial demurrage costs.

At the same time, reducing phosphine application rates simply to shorten ventilation times would create another risk. If insect pests survive fumigation, grain shipments could fail phytosanitary inspections in importing countries. As Australia exports grain to markets with a zero-tolerance policy for live insects, even a single live pest could result in an entire cargo being rejected and damage the country’s export reputation.

Grain Trade Australia says practical solutions must be found before the new regulations take effect. The industry needs more accurate detection technology, standardized monitoring procedures, additional time for degassing, and a workable transition period that will keep the grain supply chain—from elevators to rail, ports, and vessels—operating efficiently. Without these measures, the reform intended to improve worker safety could significantly slow grain exports and increase costs across Australia’s grain sector.

Tags: fumigation, Australia, export, grain