I work for a spice supplier and we are moving to require an at minimum annual test for all herbs and spices that we purchase for big 4 heavy metals, mycotoxins where recommended, and pesticide residues according to EPA MRLs. Going back a few years, these items were not really on the horizon for spice companies but times are changing rapidly and this is really something you should be requiring from your supplier now to weed out those who are still stuck in the past and ignoring these issues- the spice supply chain can be extremely convoluted and there is a lot of inferior product out there so ensure your supplier has a handle on these issues.
Lead is often associated with rhizomes (turmeric and ginger) as these grow underground where heavy metals will be found in soil, but we see (low level) heavy metals in most spices to be honest. We subscribe to HorizonScan for any spice safety alerts around the world- looking at the Q2 report there were no heavy metal issues raised, problems were with Salmonella, undeclared allergens, adulteration, pesticide/herbicide residues, and mycotoxins mainly. As we have a presence in the spice growing regions, we can exert more control over the supply chain and work with farmers or co-ops to improve good agricultural practice, and this really is pretty key to controlling these issues well as it is often this first step where problems occur, e.g. overuse of pesticides through lack of knowledge and training. In my few years here we have not yet had a problem with heavy metals and we buy many tons of herbs and spices.
The representative industry body in the US is the American Spice Trade Association, ASTAspice.org and they have lots of information on the trade, but I shouldn't really share any documents here as they are for paid members- if your supplier is a member of ASTA maybe they are able to share directly with you.
DM me if there is anything else I can help you with (or recommend you a new spice supplier!)
Edited by bensmith007, 18 July 2019 - 09:24 PM.