When is heavy metals testing required?  
States Fertilizer Soil Amendments Links
Washington All New Fertilizer applications N/A Metal Analysis requirement
Oregon All new product registrations:  Fertilizer, agricultural amendment, agricultural mineral and lime products sold or distributed in the state and required to be registered with the Department shall be limited in the level of the metals arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), and nickel (Ni)

Registration Guidelines

 

Department of Agriculture Chapter 603
California Commericial Fertilizer and agricultural mineral products: Packaged product labels for commercial fertilizer and agricultural mineral products, with guarantees of available phosphoric acid, iron, manganese, or zinc, which are derived from inorganic sources, shall include either an informational statement of laboratory test results or provide an informational statement providing the maximum levels in parts per million of arsenic, cadmium, cobalt, copper, lead, mercury, molybdenum, nickel and selenium N/A CDFA Fertilizer law and regulations
California CDFA OMRI ANY Products guaranteeing iron, manganese, zinc, or phosphates derived from inorganic sources need the heavy metals statement. N/A CDFA OMI Licensing, Registration, & Labeling Guide
OMRI Heavy Metal Labs showing levels of Arsenic (As), Cadmium (Cd), and Lead (Pb) for ANY product that contains compost, manure, vermicompost, mulch, mined minerals, soil, or ash                          
COR only: Trace Metal Labs showing Arsenic (As), Cadmium (Cd), Chromium (Cr), Lead (Pb) and Mercury (Hg) for any product that contains microbes or the products of microbial processes anaerobic digestate, compost, fulvic acid, ash, humates, or struvite		 Omri testing requirements