Exporters have been told they must prove their fruit has been cleared through a metal detector or x-ray machine before the federal Department of Agriculture will issue a permit

Queensland Strawberry Industry Officer Jennifer Rowlings said some trade partners in Russia and the UK have already blocked Australian imports, while New Zealand announced this week it would pull Australian-grown berries from its supermarket shelves.

All six states have received reports of sewing needles and other metal spikes in berries since Queensland police announced their investigation into the sabotage almost two weeks ago.

There have also been reports of apples and bananas being targeted with needles as police fear a spate of copy cats.

But no suspects have emerged and no demands have been made, according to NSW police.

"We still don't have any confirmed motivation or reasons why a person would want to do this, but all investigations are being treated as genuine," Detective Superintendent Danny Doherty said on Tuesday.

Supt Doherty described the sabotage as an act of treachery against the nation and said copy cats faced 10 years in jail.

A health warning to throw out or cut up strawberries remains in Queensland, NSW, Victoria and South Australia.

West Australian police confirmed a fifth incident on Tuesday after a primary school student bit into a strawberry with a needle inside, while a Woolworths in Hobart was also targeted.

Needles have also been found in more than 20 punnets of strawberries across NSW from Tweed Heads to Albury.

Horticulture body Growcom is urging consumers to stick with strawberries, saying only a small number of the 800,000 punnets produced each day had been tampered with.

Growcom chief executive David Thomson said police investigations and findings will shape the direction of alterations to harvesting, supplying and packaging practices across the industry.

"It's demonstrating to us as a horticulture industry the challenge we have with food security and tampering, contamination," Mr Thomson said.

"We'll be working with governments and industries to see if we can put in place procedures, protocols and mechanisms to stop this happening again."

Glass House Mountains farmer Leonard Smith said a metal detector would cost him about $30,000, but would hopefully get the rest of this season's fruit back on supermarket shelves.

South Australian producers are sourcing X-ray machines to check fruit there, while other growers have had to cut back on staff while the impact of the nationwide contamination deepens.

Mr Thomson said other measures such as tamper-proof packaging may also have to be looked at.

The Queensland government has announced a $1 million fund to help farmers bounce back and restore consumer confidence.

Mr Thomson welcomed the funding announcement but said with strawberry season almost at end in Queensland it was incumbent on other governments to help growers in their regions.

A Sydney mother reportedly found a needle inside an apple on Tuesday, while a Queensland woman has been warned after being caught sticking a needle into a banana in a shop in Mackay.

Australian Associated Press