Q: Every time I’m lathering with Dr. Bronner’s hemp castile soap, I wonder, what is castile soap? And how is it different from my bar of olive oil-based soap from the farmer’s market, or my partner’s Dove? Finally, does the ingredient triclosan in antibacterial soap really convert to dioxin in sunlight?
Susan, Washington, D.C.
Q: When my garbage disposal died recently, it led me to wonder which is kinder to the environment: putting kitchen waste in the disposal or just trashing it? I compost whenever possible, of course, but there are always scraps that are mixed with animal fat and shouldn’t be added to a compost pile.
Richard, Newburyport, Massachusetts
Umbra Fisk dispenses advice on all things green for Grist Magazine, an online publication tackling environmental topics with irreverence, intelligence and a fresh perspective. To submit a question, e-mail email@example.com .