The son of former ABC News anchor Ted Koppel, who was found dead after a day of bar-hopping with a man he'd just met, died from a lethal combination of drugs and alcohol, the medical examiner's office said today. Andrew Koppel's May 31 death was ruled an accident. Koppel. 40, died from acute intoxication due to the combined effects of alcohol; heroin; cocaine; diazepam, the generic form of Valium; and Levamisole, a drug used to cut other drugs, said a rep for the New York medical examiner's office. (More Ted Koppel stories.)