And research now links the development of an autism spectrum disorder [ASD] to parents and families being exposed to pollutants.

"In Australia and internationally for many years, the cases of autism remained stable at around one in 10,000 until the 1980s," Dr Lee Sturgeon said.

"Since then, the rate of ASD has increased dramatically."

Dr Sturgeon, a clinical and developmental psychologist at Warners Bay, will speak at a Strive For Autism seminar on Tuesday at Cessnock Performing Arts Centre.

He said the rate of ASD was - in some areas of the world [including Australia] - now "as high as one in 60".

"There are mainstream schools in the Hunter Region with higher rates than this."

For example, a local primary school with about 200 students has seven students diagnosed with the disorder.

The increase was due to many factors, including changes to diagnostic systems, greater education and awareness, and access to the internet.

The rise and recognition of environmental triggers for autism and the availability of financial support and therapy were also factors.

Dr Sturgeon said a major research finding in the past decade had been confirmation that the disorder was "primarily caused by environmental factors combining with genetics".

The development of an autism spectrum disorder was "now linked to parental and familial exposure" to a range of pollutants.

These include air pollutants, fragrances, cologne, makeup, heavy metals, air fresheners, food flavours, detergents, pesticides, insecticides, herbicides, solvents and polychlorinated biphenyls (PCBs), he said.

He added there was growing evidence that the disorder was "typically associated with a myriad of other diagnoses".

These include challenges such as gastrointestinal issues and disorders related to sleep, neurology, attention and behaviour.

"As such, the gold standard for treatment is multidisciplinary intervention.

"There is no one professional body or service that can meet the full needs of an individual with an ASD."

Professionals involved with children with an ASD from a very young age can include GPs, paediatricians, geneticists, psychologists, speech pathologists, occupational therapists, behavioural therapists, physiotherapists, audiologists and psychiatrists.

"There are now a range of more holistic therapies being included in therapy, such as music therapy, art therapy and hippo-therapy (horse riding therapy)," he said.

Research recommends a multidisciplinary approach, but this "places substantial pressure on families, particularly with regard to time management and financial outlay".

"I strongly recommend families engage in one or two therapies at a time and do these well," he said.

He preferred this approach to doing "a myriad of therapies and not having the time to really make gains in any".

Many families were being encouraged to obtain support through services such as the NDIS [National Disability Insurance Scheme].

"This can only occur through confirmed diagnosis," he said.

He said there was "growing evidence of the false diagnosis of ASD to gain therapeutic or financial support".

"Unfortunately, this is not difficult to do as ASD is diagnosed based on professional opinion on presented evidence. There is no current medical test to conclusively diagnose autism."

False diagnosis was more likely to occur when a child had a diagnosis of a "behavioural, learning, attention or anxiety disorders".

"These diagnoses do not receive the therapeutic or financial support that an ASD diagnosis does."

He said false diagnoses escalated rates of ASD, affecting funding for those genuinely living with the disorder.

"In my opinion, the diagnostic process requires much greater investigation and tighter controls and consequences for incorrect diagnoses."

He said there were many positive stories of significance that need to be shared about those living with ASD. This specifically related to socialisation, relationships, education, community access and employment.

Tuesday's seminar - which starts at 6pm - will include the inspiring and thought-provoking story of Tim and Judy Sharp. Tim is an animator with an ASD diagnosis.

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