For Grisham, this might be a mix of both
There, among the cocoanuts and the mangroves, invalids may certainly count on laying a new hold upon life
Coupled with the multiple endpoints of interest and myriad exposures (note that this does not just mean the list of product categories, though that is long enough, but also specifics of the products, dosage, and other variables), a literature an order of magnitude larger than what exists, and with average quality of at least that of the 75th percentile of quality for this literature, would only begin to be informative
The most popular one is Nicotiana tabacum which has various groups of leaves: Lugs: the lowermost 4-5 leaves Cutter: middle leaves Upper-stalk: leaf and tip What is worth noting, the higher the leaves, the higher the nicotine concentration in them
Additionally, there are also tests for unspecified impurities, which can not be more than 0,1%