Data Views Total Plants: 21 CSV Excel PDF Total Activities: 7 , Previous12 Show all rows. Paginate rows. Click on column headings to sort table by that column Plant Part All Fruit Leaf Plant Seed Shoot Low PPM High PPM StdDev *Reference Thymus vulgaris Plant -- -- Stitt, Paul. Why George should eat broccoli. *Unless otherwise noted all references are to Duke, James A. 1992. Handbook of phytochemical constituents of GRAS herbs and other economic plants. Boca Raton, FL. CRC Press.