"Hospitals are very focused on this and they are looking at their quality assurance that's in place now," she said.
"I've also written to the hospitals and said, you have a responsibility to assure quality assurance of the drugs you are purchasing."
Marchese Hospital Solutions has come under scrutiny since it was discovered that 1,200 patients in Ontario and New Brunswick received diluted drugs purchased from the company, some for as long as a year.
Too much saline was added to the bags containing cyclophosphamide and gemcitabine, in effect watering down the prescribed drug concentrations by up to 20 per cent.
Hospital officials have said it's unlikely it had much of an effect on patients, since the drug-and-saline mixture would have been diluted further and mixed with other chemotherapy drugs before being administered.
But the province and Health Canada have since acknowledged that there was no oversight of Marchese Hospital Solutions, and they don't know how many other companies like Marchese are operating in Canada.
A new survey by the Ontario Hospital Association sheds new light on how widespread the outsourcing of medication mixing is in the province.
It said 11 hospitals reported that they buy "ready to administer" drug mixtures from Marchese — that is, mixtures which don't require any further manipulation by the hospital pharmacy, unlike the ones involved in the drug scare, the OHA noted.
One hospital is using Marchese for stock solutions of epidurals that are then mixed in house.
None of the 88 acute-care hospitals who responded to the survey were using Marchese for bulk or stock chemotherapy drug mixtures, the OHA said.
But 40 of them said they're buying "pre-compounded IV medications in a ready-to-administer format" from external providers — mainly epidurals, narcotics and antibiotics, the OHA said.
Outsourcing drug mixing is nothing new, the survey found. Twenty of the 40 hospitals have been doing it for more than five years, and 15 have been doing it for for two to five years.
Most cite patient safety as the main reason for switching to an external provider, rather than mixing the drugs within the hospital pharmacy. Twelve hospitals cited cost as a reason for switching, the OHA said.
NDP health critic France Gelinas said she's concerned that 11 hospitals are using Marchese because there's no oversight of the company.
"There are providers that don't fall under any regulation whatsoever, and it doesn't look like the minister of health is in any hurry to look at this more closely and to take her responsibility of oversight," she said.
"So it is worrisome."
Marchese has said its products weren't defective, and suggested that the problem wasn't how the drugs were prepared but how they were administered at the hospitals.
The diluted drugs were discovered by an "astute" pharmacy technician at a Peterborough hospital that had just switched over to Marchese, a legislative committee has heard.
It also heard Tuesday that Marchese didn't provide the same information on its labels than their previous supplier Baxter Canada.
Both labels met standards and provided the total amount of the drug in the bag, said Leslie Motz, senior director of clinical services at Lakeridge Health hospital in Oshawa.
But Baxter's labels provided a per-millilitre concentration of the drug, whereas Marchese's didn't.
She said Marchese also had barcodes on their labels, which allows hospitals to manage their inventories quickly. Baxter didn't.