Physical Danger
More than you might think. While out in the field, you may find yourself near deep water, testing rock or soil on treacherous terrain, or exposing yourself to areas that contain a health hazard. Back in the lab, you may be working with toxic chemicals. Remember those three-eyeballed fish from The Simpsons? You'll be bathing with 'em in the field.
You also have to be careful when flying your jet pack between work and home. (You didn't think they drove cars, did you? Scientists do get some perks, you know.)