Journalism can be, LameR. Journalists have been killed in conflict zones, singled out for beheading - remember that horrible video? Agreed, not the usual job description but definitely more than event planning.
But personally I see the most stressful jobs as the endless, repetitive, low pay, dead end. Because firefighters, police officers, ER doctors - they chose that. They are people who for whatever reason, more power to them, thrive on the edge. And they are usually well rewarded with both pay and prestige. But a woman in some Third World country sewing clothes or shoes 18 hours a day for pennies, subjected to sexual harassment or assault by boss, children left with any relative who can keep them, in rooms without proper heat/cooling, ventilation or restroom facilities, breathing dust and fumes, no sick days, over and over and over, day after day, no relief in sight and no options. To me that endless treadmill is the ultimate stresser.