An Aussie mum is appealing for her missing son to make contact with a doctor after it's been found he could have high levels of metals in his body.
Karl Melo-Richards, 25, from Maroubra, NSW, went missing on September 2 last year and hasn't been seen since.
New evidence has come to light as to why he might have been feeling depressed and anxious before his disappearance.
Before Karl went missing, he had hair samples taken and recently those tests came back to show he had up to ten times the usual levels of aluminium, lead and uranium in his blood.
His mum, Vanessa Richards, 50, says these high levels of metals could account for him feeling depressed since he was a teenager.
'A build up of heavy metals in the body can cause deposits in the brain. Levels as high as Karl's can lead to insomnia, depression and anxiety,' says Vanessa.
It's possible that Karl could have come into contact with the poisonous levels of metals through surfing in metallic waters or through his job as a carpenter.
Vanessa is appealing for Karl to seek out a treatment called chelation to draw out the metals in his bloodstream.
'Even if he doesn't come home, I hope my message to see a doctor reaches him,' said Vanessa.
Have you seen Karl?
Karl Melo-Richards is described as being of a caucasian appearance, 175-180cm tall, broad-shouldered and a fit build, close cropped brown hair and brown eyes.
When he was last seen, he was wearing a T-shirt, dark blue jeans and DC brand shoes with a distinctive white sole.
He was carrying an SDS brand blue and grey backpack. Anyone with information is urged to call Maroubra Police on (02) 9349 9299.
If you or anyone you know is experiencing severe depression or suicidal thoughts, call Lifeline on 13 11 14 or visit www.lifeline.org.au.