Vessel enroute from Gedney Island to Everett Marina, powered by gasoline engine.  Operator smelled fumes below deck and had all passengers come topside.  as the vessel neared Everett Marina, juvenile Male went below to use head.  Jevenile was overcome by carbon monoxide, fell and hit his head.  Juvenile Male has history of athsma.  everett Fire Dep. respodend and contacted the vessel after it docked.  Juvenile male was transported to Providnece Hospital by Ambulance for further observation.

OPeartor stated the casue of the CO2 leak was a hole in the exhaust hose.
Everett                       