Data Views Total Plants: 103 CSV Excel PDF Total Activities: 13 , Previous123456 Show all rows. Paginate rows. Click on column headings to sort table by that column Plant Part All Bulb Flower Fruit Leaf Rhizome Root Seed Shoot Sprout Seedling Stem Tuber Pt Low PPM High PPM StdDev *Reference Apium graveolens Pt 270.0 5035.0 USDA's Ag Handbook 8 and sequelae) Brassica oleracea Stem 70.0 780.0 * Allium cepa Bulb 230.0 2230.0 USDA's Ag Handbook 8 and sequelae) *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.