Health Canada is pulling the last of citronella-based bug sprays off the shelves by the end of December because of "the absence of adequate safety data.” The essential oil has been used as an insect repellent in Canada for decades.

The move has left scientists who advised Health Canada on the issue befuddled by the ban. So are many consumers who prefer natural bug sprays over ones with synthetic chemicals like DEET.

It's the basis of the ban that I don't really understand - Sam Kacew, Toxicologist

"It's the basis of the ban that I don't really understand,” says toxicologist Sam Kacew.

Insect repellents are considered pesticides so they must meet strict safety standards. In 2004, Health Canada proposed phasing out citronella-based bug sprays because of new questions about its safety.

Small manufacturers who couldn't afford to submit detailed safety data saw their lines discontinued at the end of 2012. Those who submitted what data they could and tried to challenge the ban are now to see their products phased out at the end of this year.

In 2005, Kacew sat on an independent scientific panel to review Health Canada’s position. He says the panel believed the study that led the government to question citronella’s safety was flawed, in part because it examined what happened when rodents ingested the oil. “Humans are not going to drink citronella,” he says.

The department told CBC that “the panel supported Health Canada’s approach,” but Kacew refutes that. He says the team of scientists concluded that citronella was safe as long as it didn't contain methyl eugenol, an impurity that could be a potential carcinogen. “In general, most of these citronella oils that were available for us to examine did not contain impurities, and they were regarded by us to be basically safe,” he says.

Companies pay the price

Montreal company, Druide, has been selling government-approved citronella sprays and lotions since 1995.

“Where I am very sad is, in the end, [Health Canada] doesn’t have anything against citronella, except questions about it,” says Druide’s owner, Alain Renaud.

Citronella bug sprays are back in production after Health Canada flip-flopped on a plan to phase out the product. (CBC)

He says he spent five years proving to Health Canada that his repellent didn’t contain methyl eugenol.

But Renaud says that as soon as he won that battle the government "came back and said we still have questions and we need a complete toxicological report on many generations of animals.”

That may be a standard approach, but Renaud eventually gave up his fight because his company doesn't believe in animal testing, and didn’t have the estimated $1 million needed to fund a large-scale scientific study.

Druide's citronella-based bug spray was a bestseller for the company, which manufactures organic personal care products.

Renaud says he’s had to lay off five employees because of the ban and has lost up to a million dollars spent on marketing his product and providing research for Health Canada. “At the end of maybe, five, 10 years of fighting, [Heath Canada] gets all our energy,” he says.

DEET passed Health Canada’s scrutiny because the manufacturers provided the required safety data. But citronella — an extract from lemon grass — has never been patented, which makes it an unattractive investment for costly studies.

“If the market was such that this product was generating millions of dollars, then the industry would have done something re-active to try and get [citronella] back on the market,” said Kacew.

That’s the problem with other essential oils as well. They may be effective as bug repellents, but no one has yet funded the studies to prove they’re safe.

DIY bug spray

Tracey TieF made and sold a natural bug spray with essential oils including lavender and rosemary for seven years before Health Canada shut her down recently.

The problem was that she hadn’t registered her product and done any safety studies.

“I can’t afford to run my own trial,” says the certified health practitioner. “I feel afraid and I feel sick about it, actually, because for me, this is a passion.”

TieF now puts that passion into teaching others how to make natural bug sprays. In a tiny room at Karma Co-op in Toronto, she passes out bottles, essential oils and recipes. “I’ll teach people until [Health Canada] stops me,” she vows.

Aimee Alabaster says she joined the class because she wants a natural bug spray for her children. “Everything out there for the most part contains DEET, and I don’t want to put DEET on my kids.”

Research has suggested DEET could be harmful to the central nervous system. But Health Canada states on its website that “registered insect repellents containing DEET can be used safely when applied as directed.”

Come 2015, citronella bug sprays won’t be entirely out of reach, you will just have to cross the border. The product will still be available in the U.S.