A retired forensic toxicologist is calling on Nova Scotia to stop using hair-based drug and alcohol testing, arguing it is a "developing science" that shouldn't be used in child protection cases until more in known.

"It's an emerging discipline," said Albert Fraser, who worked at the Victoria General Hospital in Halifax for 25 years. "But it's not a mature scientific discipline."

Albert Fraser

Retired forensic toxicologist Albert Fraser says hair-based drug and alcohol testing is a 'developing science.' (Submitted by Albert Fraser)

Ontario and New Brunswick have both ordered child protection agencies to stop using hair testing after serious shortcomings were found at the Motherisk lab at The Hospital for Sick Children in Toronto.

Motherisk also conducted tests on as many as 2,300 people in New Brunswick and Nova Scotia, a CBC News investigation has revealed.

Between 1997 and 2005, hundreds of those people produced at least one positive test result indicating the use of drugs or alcohol. The hospital now admits those results may be "inaccurate or unreliable."

After discovering problems at Motherisk, the Ontario government told all social services agencies in the province to stop using hair-strand drug testing "out of an abundance of caution" last April.

A reversal in New Brunswick

New Brunswick followed suit and stopped using the tests, citing concerns about the "overall reliability" of hair testing.

Until then, the province was still ordering hair tests from Dynacare, an Ontario-based lab that says its testing is "robust" and provides "high-quality analytical toxicology service for analysis of drugs-of-abuse in hair."

Meanwhile, Nova Scotia continues to conduct hair testing. Andrea Price, a spokeswoman with Dynacare, confirmed the lab is still performing tests for Nova Scotia. She declined to comment on hair testing moratoriums in other provinces.

However, in a statement to CBC News Monday, Heather Fairbairn, a spokeswoman with Nova Scotia's Department of Community Services signaled there could be a change coming. 

"Now that the science behind hair strand testing itself is coming into question, the department is considering the value it may offer to our clients and will be looking at alternative options," Fairbairn said.

"Hair strand analysis was just one among a number of tools the department may employ in child protection cases. However, these results alone would not be the single determining factor in the outcome a case."

Not meeting forensic standards

A review into Motherisk's practices found the lab didn't meet international forensic standards and its leaders had no formal training or experience in forensic toxicology. The lab shut down its hair-testing operations for good last year.

According to Fraser, a forensic lab requires high security because samples may be used in court. Each step of the testing is carefully documented so there's less chance of contamination.

"Almost anything you would think of as being a requirement for forensic identification for a drug in a biological fluid, they didn't follow forensic conventions at all, which is most unfortunate," Fraser said. "It's a tragedy."

But the forensic toxicologist's concerns with hair-based drug testing go beyond Motherisk.

He questions whether the science should be used at all in child protection cases.

'A lot of unanswered questions'

Part of his concern comes from the "colour bias" involved in hair testing.

Because of the different pigments found in hair, Fraser said someone with darker hair may absorb drugs in much higher concentrations than someone with grey or blonde hair.

"It's problematic if one wants to relate the amount of drug that is present to the extent of drug abuse by the individual who had that hair that was being tested," Fraser said.

The concerns are different than with blood or urine testing, which Fraser said has been used "a thousand-fold" more often than hair testing.

He said Nova Scotia should stop all hair testing until it learns more about the science.

"It isn't that hair testing won't have a role," he said. "But you can't go to something that's developing and make that your absolute, because there are still a lot of unanswered questions about the technology."

Still being used in courts

The debate around hair testing is also being waged inside courtrooms.

As recently as February, a judge in Sydney was faced with conflicting drug test results from three different labs, including Motherisk.

Justice Lee Anne MacLeod-Archer set aside all drug testing evidence.

She returned the children to the care of their mother, who insisted she hadn't used drugs in months.

"The evidence is insufficient to prove reliability of those reports for purposes of this proceeding," MacLeod-Archer wrote in her ruling.