A 57-year-old woman will face court on Thursday charged with contaminating food at two Brisbane Sizzler restaurants with rat poison.
Queensland Police Inspector Bob Hytch said the woman was charged over the contamination of the salad bars at Sizzler's Toowong outlet on January 20, and at the Myer Centre in the city last Saturday.
He said it was the same woman police had urged to come forward on Tuesday, and who had told Sizzler's staff at the Myer Centre she found green pellets in her vegetable soup.
"I would like to stress that the police investigation is ongoing and this is the first step," Insp Hytch said.
He said there have been "no threats or demands" in relation to the incident and there was no evidence so far that any other stores were affected.
The woman, from Brisbane, was arrested in the CBD and charged with two counts of contamination of goods and four counts of an act intending to cause grievous bodily harm.
She will appear in the Brisbane Magistrates Court on Thursday.
Sizzler Australasia managing director Bo Ryan said despite the arrest, he expected the self service salad bars at the company's 28 restaurants nationwide to be shut down for between seven and 10 days.
"This issue has highlighted some shortfalls in our product security management and we have a couple of things that we need to complete at this stage before we will introduce procedures to every restaurant in the country," he said.
Mr Ryan said the shutting down of the salad bars will cost the company millions of dollars.
"We are talking about an awful lot of money, in the sales environment its hundreds of thousands of dollars each day," he said.
Sizzler has been criticised over the time it took for the results of the first contamination to be made available.
The company sent the sample to Brisbane laboratory Biotech on January 20 and they were then sent off to AgriQuality New Zealand for further analysis.
The results returned last Monday and authorities were informed.
Health Minister Stephen Robertson said the slowness of reporting the results showed the restaurant chain had not "come through this in a particular flash way".
"I don't think Sizzler handled this particular case well at all," he said.
"They sent it off to a private overseas laboratory instead of alerting Queensland Health and utilising our services which could have had the turnaround of a couple of days to determine what the foreign matter was."
Mr Robertson said the recently passed Food Act 2006 would be toughened up with the inclusion of mandatory reporting of cases where the tampering of food is suspected.
It will also include protocols to ensure whenever there is food tampering businesses will know the correct procedures and responsibilities.
"We don't want to tie the industry up with red tape or unworkable requirements," he said.
"What we want is something that is very practical, easily understood and easily implemented to give Queenslanders confidence the food they are eating is safe."