AN AUSTRALIAN man is being held in Phuket Prison over possession of chemicals that police say could have been sold for as much as 200 million baht.

The man was arrested on Monday and refused bail. It is understood there was an outstanding warrant for his apprehension.

The chemical involved is a base ingredient in the methamphetamine known in Thailand as ya-ice.

Police named the man as Youssef David, 25. Officials at the jail said Mr David had had visitors from Australia.

The jail, in Phuket City, was built to hold 700 but has more than 1100 inmates at present.

Simon Burrowes, a British citizen who was forced to spend time in the jail earlier this year for swearing at an Immigration officer as he tried to leave the country, recently wrote to Phuketwan in response to a favorable report about the jail.

He described it like this:

''I was in Phuket Provincial for three weeks. My bed space was 55x60cm next to a man unwashed in two years. At least two prisoners have unsightly sores that people avoid them for in spite of intimidatingly administered assembly rules. The guards empathise. One I was told 'cuts onions'.

''At least half of my 126 man cell wear bandanas all night because the open toilets are in the cell. Masturbation and unallowed smoking take place there, generally accepted. The katoeys [lady boy transsexuals] use a bucket in theirs that they empty daily. In the open sewage moats there is, granted seldom, human faeces.

''The birds and the flies in abundance gorge your generally nutritionless food before you get to it. I had an embarrassing but scary sore within days of being there. The 'doctor', speculatively unqualified, gawped at it with his lazing around mates in the waiting room as opposed to the surgery. He winced and walked away from me.

''A lackey of his told me 45 minutes later that it was doubtful that he'd tend to me. Doubtless the media saw prisoners in uniforms as they wore on the 'Big Trouble in Tourist Thailand' doco. The ones we had to wear when visitors came or we went to court or any time the outside world could see us.

'' I was even sent back to shave on my first visit, that was officially 10 minutes but routinely cut short with impunity. Myself and another farang [westerner] complained that farang always got a humiliating deal, even to a mound of facaes in uniform shorts to wear on visits. We were ridiculed by the top officer.

''When dignitaries visited, we were locked, squashed up indoors while a select few in uniform walked around pretending all was well and earned brownie points.

''As an officer told me, any of our vetted post will be stopped if anything negative about the prison is written to the outside.''

Mr Burrowes sent Phuketwan his commentary from Britain. What he wrote clearly has no bearing on the guilt or innocence of the inmates, some of whom are awaiting court hearings, only on the conditions at the jail.