In the majority of cases, yes. As always, be alert to vendors with food and equipment that is visibly unclean, but generally speaking, most people can sample Mexican street food without serious gastrointestinal repercussions. In fact, tasting street food is one of the best Mexican travel experiences out there. If there's a line in front of the vendor, chances are you stumbled across something good. And if they say the salsa isn't that spicy, try a dab before dousing your food. Your lips, esophagus, and colon will thank you.