Here is an excerpt from a very good article/protocol on mercury/heavy metal chelation as it pertains to cilantro.
"Cilantro should be used only after a good chelation program has been under way for some time. Cilantro can enter the brain and peripheral nerves and remove mercury. But unknown to most, cilantro can also take mercury into the brain. This is why it is critically important to use cilantro only after most of the mercury has been removed from the rest of the body. Do not use cilantro until at least 60 days has elapsed on any oral chelation program.
Buy fresh organic cilantro. Wash and put approximately 1 cup in blender with small amount of water. Add 1/4 tablespoon of Sea Salt and 2 tbs of cold pressed olive oil. Blend until creamy.
Take 1 tablespoon 3 times daily with meals. May by used as a salad dressing. Use more if mercury toxicity is profound enough to cause depression, Alzheimers or brain fog."