May I add a little information to the general process of OCME patient evaluation? Promise to be brief, for a change!
The decedent is removed from a death scene with care, a NEW, unopened body bag is utilized. Frequently there is a temporary "shroud" placed over the victim, many (in some jurisdictions, ALL) first responders have NEW, unopened tarps/sheets that are used and if ANY coverings are used, they come with the decedent to the OCME in either the transport (body) bag OR in evidence bags. EVERYTHING on or near the decedent is acknowledged, photographed & collected (every single time in a perfect world!).
Arriving @ the OCME, the decedent is entered into the system, assigned a full case # & that # stays with the case. Keeping every possible piece of evidence in tact & "pure", as in NOT contaminated by any other case or individual is standard behavior, in the beginning of a case, that which is "THE CLUE" is unknown so great care is necessary! The body is observed, externally evaluated CLOTHED & everything is evaluated/described/frequently photographed. As the body is undressed, each clothing item is evaluated over a fresh sheet of paper (think the brown "butcher paper" on a huge roll!). Also hair (ALL) is fine-tooth combed over the paper, detritus from under nails (ALL, if appropriate) is collected on the paper and/or swabbed for DNA testing.
SO.....just from this brief example, one can see that there's plenty of "stuff" to evaluate for foreign substances.
In THIS case, the pollen in the bag probably came from the clothing/hair as it was "washed" via the moisture within the bag (think that the bag created a greenhouse effect).
