A leading New Zealand neurologist has warned that essential oil diffusers "have no place in classrooms" saying they can cause seizures in children with epilepsy.
Professor Gareth Parry, who is an Officer of the New Zealand Order of Merit for services to neurology, said eucalyptus oil and rosemary oil were just two of 11 essential oils that potentially caused seizures.
He was speaking out in response to news that an Auckland primary school stopped using diffused oils in 20 classrooms after it was threatened with High Court action.
Auckland lawyer Tim Rainey, threatened legal action against his son's school, Milford Primary on Auckland's North Shore, which started using diffusers and essential oils in class this week.
Rainey said the oils were triggers for his asthmatic son.
The electric diffusers - supplied to the school through multi-level marketing company dōTERRA - work by dispersing a mist of water and essential oil molecules throughout the room.
Professor Parry supported Rainey's claim and said while there was little risk for children without the conditions it was significant for an epileptic or asthmatic child.
"The big concern with is that with the incidence of epilepsy in children there will undoubtedly be a child at the school with epilepsy.
"We need to educate parents about the risk to their children if they are exposed to essential oils."
Professor Parry had just returned from India where he had lectured on risks of remedies with convulsant properties.
He said he was not trying to stop the use of essential oils but wanted to see full disclosure and a careful public education campaign on some of the dangers.
"Something we have known for 500 years is that some are epileptogenic - they cause seizures.
"So if the decision is made to still use them in classrooms parents of epileptic children need the option of removing their child from the class when they are being used."
An expert in essential oils also warned against their use without expert and individual advice.
Clinical Aromascience Practitioner Gillian Parkinson was concerned about the increasing number of daycares and schools in New Zealand using diffusers.
The NZQA qualified practitioner was so concerned with the increase of incorrect use - such as adding essential oils to foods, overuse and undiluted use - her business had become more about education than promoting use.
"There are oils that are completely safe to use for children up to 12 years but as prescribed amounts for a certain reason and only for a short time.
"Overexposure to harsh anti-microbial oils like the ones in OnGuard can actually prevent children building natural immunity as well as enable adverse reactions such as headaches, irritability, watering eyes, unexplained rashes, and respiratory problems."
Parkinson said New Zealand needed stricter regulations so only qualified practitioners could manufacture and sell essential oils.
"This is not about looking after my business it is me worried about people's health and wellbeing."
Ministry of Education spokeswoman Katrina Casey said school boards had the power to make decisions on a wide-range of matters.
"However we do expect that schools consult parents and their community about decisions they make that may affect students - such as the use of oil diffusers," she said.
The president of the New Zealand School Trustee Association Lorraine Kerr did not think the use of essential oils in class was widespread.
She had not been contacted by any school seeking advice on essential oil use.
"The use of anything like this is the decision of the board of trustees," Kerr said.
"And so are any consequences."
The global communications manager of American brand dōTERRA, Jennifer Lambert, stood by the product as safe but said its use in schools depended on a variety of factors.
"Despite it being safe, school and class usage depends on various factors, including school policy and the preferences of students and parents," she said.
"It is always recommended to consult with healthcare providers for specific needs or questions."