erineum mites in lettuce
The best way to remove the mites is to submerge the lettuce in cold water for at least 10 minutes. The ice cold water will do a few good things to your lettuce. It will drive out those pesky bugs, hydrate any dirt on the leaves, and cause all of it to sink to the bottom of the sink. It will also make your lettuce nice and crisp.
Once you are satisfied that all of the baddies have drowned, spin your lettuce dry in a salad spinner or a tea towel and refrigerate it until you are ready to eat.
Once the mites have been drowned and rinsed off, the greens are perfectly safe to eat. Actually, it should be safe to eat the mites as well, it's just unappetizing.
Hope this helps!