I would suggest simply using some good cleanses/detoxes on a fairly regular basis and using the combination of cilantro and chlorella to help remove any heavy metals. Jon Barron has an enhanced product that contains those items called Blood Support.
Selenium is also good for binding with heavy metals and removing them.
Other than that, follow a good healthy diet and lifestyle and make sure that all the nutritional bases are covered. An excellent product you might want to consider is intraKID.