AN 18-year-old chemical student sparked a major alert after causing an explosion at his uncle's home with an experiment that went wrong.

Christopher Cookson was left horrified and stunned after mixing copper oxide and magnesium at a house in Pleckgate Road, Blackburn, at 3.50pm yesterday.

Christopher, an A-level student at St Mary's College, Blackburn, today told how the explosion filled the room with a bright, white light and powder flew into his eyes and mouth.

Christopher, of Beryl Avenue, Roe Lee, said: "I tried to stay calm and phoned the chemical company that had supplied me with the chemicals.

"When I told them what I had mixed together they told me to call 999 for an ambulance immediately.

"When the ambulance arrived, they insisted that I had a shower before they would look at me and when I got out of the shower, the house was full of police, firefighters and people from the fire brigade's chemical support unit in specialist suits.

"I had tried to stay calm but when I saw all the people I began to worry.

:I was worried that the substance I had inhaled was toxic and also that it was flammable and unstable after seeing it explode so violently and worried what it could do to me.

"I also have asthma and paramedics thought the chemicals may irritate my chest condition."

Christopher lives with his parents and said they were shocked to find out what had happened.

His uncle Steven Cookson said: "I was out all afternoon and when I came home the house looked completely normal.

"I couldn't believe what Christopher had said had happened.

"To be honest he is always doing things like this and I just thought what has he been up to now?"

Fire crews investigated how the chemicals had been stored.

They questioned Christopher on what he had been doing before he was allowed to go for treatment at hospital.

Evening Telegraph medical expert Dr Tom Smith said: "Magnesium is a very volatile metal and when mixed with the oxygen, in reaction with copper oxide, it will have expanded very quickly, thousands of times.

"That is what caused the explosion.

"In this case, a solid has gone straight to a gas without first going through the liquid phase.

"It is a very unstable process as the air compresses very quickly. This is the principal of most explosions.

"He could have received lung damage as a result and also damage to his ear drums and haemorrhaging in the back of the eye because of the pressure."