Can the lead level of herb products be lowered?
The lead content of soil—that was affected strongly during the last half of the 20th Century by industrial and automotive use of lead—will decline gradually, and plants will eventually have less content of lead as a result. However, because the levels required by Proposition 65 to avoid warning labels are so low, this change will not alter their regulation in California. Once lead is in the plant materials, it can’t be removed. It is possible to make various extracts of herbs that might leave a larger portion of the lead behind in the portion thrown away, and this can be done with alcohol extraction. However, along with leaving behind the lead, several of the desired active ingredients may also be left behind. Some tinctures are very low in lead, but also provide very little other materials from the herbs, and are labeled with very low dosing, so they may avoid Proposition 65 warning labels (based on total daily lead intake) but they also provide almost no active components.
