~ Food Has Power ~
Breastmilk is a detox pathway. So, we don't want to do anything to dump more toxins into our blood circulation than our urine/feces can excrete. Sweat is another detox pathway which bypasses breastmilk.
Basically, the detoxification system is like a funnel. We can dump a lot into blood circulation but we have a narrow exit.
For sensitive baby, I'd be concerned about folate, B12, magnesium, zinc, molybdenum and selenium. Many medications deplete B-vitamins, especially folate and B12, and magnesium and zinc!
Chlorella doesn't bind heavy metals according to Andy Cutler, author of "Amalgam Illness". Due to 1-thiol group chemical bonds (vs. 2-thiol group).
Epsom salt baths can help provide both magnesium and sulfate to support the natural detoxification pathways. We can increase the supply of probiotics, vitamins and minerals in breastmilk by focusing on nutrient-dense foods ourself.
Some herbs will optimize our own digestion which in turn increases the bio-availability of nutrients to us and baby. Herbs (bitters) which improve stomach acid would be my first thought. Chamomile, nettles, dandelion are nourishing bitters which support digestion and are safe while nursing. I'd be a cautious with dandelion if you have/had mercury issues though.
Susun Weed's book, "The Childbearing Years" is an excellent resource: http://www.amazon.com/Wise-Woman-Herbal.../dp/0961462000