A GYM boss accused of killing a 28-year-old with weight loss drugs in High Wycombe said he could not even touch chemicals in case they killed him, the Old Bailey heard.

Peter Purkins, 47, is accused of supplying a lethal dose of DNP to Sean Cleathero at the gym he co-owned in High Wycombe.

Purkins, business partner Jamie Chivers, 44, and employee Jason King, 41, are accused of manslaughter by gross negligence for selling the drug to Mr Cleathero, which killed him on October 16, 2012.

They are said to have supplied DNP, an industrial chemical used to burn fat, through their illegal steroid dealing business, run with a fourth defendant, Laura Hague, 23, which used the Apollo Gym as a front.

But Purkins told police he could not touch chemicals anymore because past drug abuse had left him with a weak heart.

"If it soaks into my pores, I would be dead", he told detectives.

"I would never sell it to someone wanting to lose weight - I would tell them to do it by exercise and diet."

Purkins denied handling DNP, and said he had not touched steroids since he and Chivers were convicted in 2011 of supplying steroids through their firm, HGH laboratories. The court heard Mr Cleathero, who was clinically obese and had sometimes used steroids and amphetamines, was dead within eight hours of taking DNP, which was handed to him by King at the gym.

Purkins is accused of arranging for the slimming drug to be delivered to the gym by Chivers, which he denies.

He said he and Chivers set up the gym because "Wycombe needed a proper gym for a long time".

Chivers admitted at the start of the trial supplying steroids through a new business, Precision Laboratories, but Purkins denies being involved.

He told officers Chivers signed the gym over to himself, cutting out Purkins, in the weeks prior to Mr Cleathero's death.

Chivers has admitted trying to pervert the course of justice by deleting CCTV and clearing out the HGH lab following Mr Cleathero's death.

He was caught on camera deleting the footage of himself delivering the drugs sachet to the gym.

Chivers, of Spring Gardens Road, High Wycombe; Purkins, of Heather Walk, Hazlemere, and King, of Hazell Road, Prestwood deny manslaughter.

Chivers has admitted two counts of conspiracy to supply class C drugs and two counts of perverting the course of justice.

King also denies two counts of conspiracy to supply class C drugs and perverting the course of justice.

Hague, of Orchard Grove, Chalfont St Peter denies two counts of conspiracy to supply class C drugs and perverting the course of justice.

The trial continues.