A staff exodus at the national pesticides authority before its move to Armidale has smashed its on-time product approval rate, which has halved in six months.
Approvals for new products meeting required timeframes plummeted from 83 per cent in the September quarter to 42 per cent in March after the decision to relocate the Australian Pesticides and Veterinary Medicines Authority.
A surge in resignations since the move was announced has hit pesticides approvals particularly hard, as the agency registered only 30 per cent of new crop protection products on time, compared to 82 per cent six months ago.
But a spokesman for Nationals leader Barnaby Joyce, the driving force behind the APVMA's move to his New England electorate, denied the relocation was to blame for the falling rates and said they showed the agency should relocate.
Agricultural chemical industry peak body CropLife said the figures were the worst in the agency's history and showed the forced relocation was affecting the APVMA's performance, putting farmers at a disadvantage to their competitors overseas.
Plummeting on-time approvals prompted CropLife chief executive Matthew Cossey to urge the government to reconsider moving the agency from Canberra, warning the delays risked losing the farming sector billions in revenue.
"This latest performance report surely signifies that it is time to stop and reconsider the decision to relocate a crucial agricultural regulator that is dependent on technical scientific specialists for which there is a global shortage," he said.
"Urgent action is now well overdue to save the regulator from getting to the point of not being able to register agricultural chemical products in timeframe at all."
While the loss of regulatory scientists has previously hit approval times for pesticides, the fall-out from the relocation has spread to veterinary medicine products used by livestock farmers and pet owners.
The rate of veterinary medicine products approved on time dropped from 87 per cent in the December quarter to 58 per cent between January and March.
Mr Joyce's office said another timeframe performance measure - which included paperwork and less complex approvals - was comparable to figures in March 2016, before the relocation was announced in October.
However crop pesticides industry advocates say this figure improved under operational changes at the agency, and that the relocation had reversed the positive trend.
Animal Medicines Australia executive director Ben Stapley urged the government to arrest the fall in on-time registrations by investing in regulatory science capability in Armidale, automation and IT.
"The assessment figures show a comprehensive intervention is needed if there is to be an improvement," Mr Stapley said.
Rising approval times risked deterring global companies from investing in the nation's market of animal medicines, barring farmers from product advances that could improve productivity, he said.
Mr Cossey said the government should consider compensating registrants for losses.
Twenty regulatory scientists and an additional 28 staff members, with 204 years' service between them, left the agency between July and February.
APVMA boss Kareena Arthy last month confirmed she would leave the agency before its move to Armidale, shortly after the National Party announced it intended to massively expand its policy of "decentralisation" or shifting public service agencies out of Canberra and other capital cities and into regional Australia.