* Clowns Without Borders works in conflict zones
* One million Syrians refugees live in Lebanon
* Aid workers say children traumatised
By Oliver Holmes
JAB JANINE, Lebanon June 3 (Reuters) - Does aid work always have to be serious? Do you have to be a doctor working on the frontline or an aid worker distributing food to refugees? David Clay, a clown from Oregon, thinks not.
Once a construction worker, Clay now volunteers for Clowns Without Borders, an international non-profit organisation that uses laughter to relieve suffering among children in refugee camps, conflict zones and natural disaster areas.
On Monday, Clay dressed up in his navy blue suit, crooked black hat and a polka dot tie to entertain 200 Syrian refugee children who are now living in neighbouring Lebanon.
The tiny Mediterranean country hosts one million refugees, who have fled cluster bombs, chemical weapons and al Qaeda militants in a war that has killed more than 160,000 in three years. Lebanon has not allowed official refugee camps, so many families live in unfinished buildings and wooden shacks.
Clay, along with three other clowns - another American, a Chilean and Lebanese - juggled, played instruments and acted like buffoons for the children, who first appeared withdrawn but started to cheer and clap as the performance unfolded.
Describing himself a humanitarian, Clay has worked in Indonesia, the Philippines and Haiti. In Haiti, where a 2010 earthquake killed more than 250,000 people, Clay said other aid groups were originally suspicious of his work, dubious of the results in a high stress situation with limited resources.
"Doctors were cold to us. But their attitude changed distinctly," he said, preparing for the show at a school in central Lebanon, multi-coloured handkerchiefs hanging out of his back pocket.
"When the doctors heard those people laughing, especially in the children's ward, they saw that it was the first time some of the children had reacted to anything at all after the earthquake."
This trip is sponsored by Layan, a Kuwait-based aid group, and the team will take their stilts, Hula Hoops and blue trombone to camps over Lebanon during the next two weeks.
One million Syrian refugee children live in the region, millions are trapped by conflict inside Syria and public health researchers and aid workers say they are displaying symptoms of psychological trauma. Aid group Save the Children says one in three children it surveyed last year had seen a close friend or relative killed.
During the singing and the dancing on Monday, Clay pulled a young boy, Ahmed, from the audience up from the crowd and gave him a wooden mop to ride like a horse around the dusty playground.
The boy's teacher said Ahmed was exceptionally shy in class and had fled from the Syrian city of Raqqa to get to Lebanon.
Raqqa has been repeatedly bombed by Syrian air force jets and is also a focal point of fighting between Islamic insurgent groups. Al Qaeda-linked fighters have carried out public executions in Raqqa's main square.
Ahmed did not appear to like the attention as he followed Clay around the audience, but the other clowns asked the children to encourage him.
A broad smile slowly filled his face and he picked up speed as his friends shouted: "Ahmed! Ahmed! Ahmed!" (Editing by Philippa Fletcher)