Here's a little info from wikipedia:
Soap Nuts are natural soap berries that the Johnsons have been importing from from South Asian counties like India and Nepal since 2008. They contain large quantities of saponin in their shells and as such, act as a natural detergent. The reason they are considered eco-friendly is not only because they are a natural resource but also because they are antimicrobial and biodegradable.[7"
...and that's all folks!