Embalming fluids are often complex mixtures of different chemicals, including:
(1) alcohols
(2) phenols
(3) formaldehyde
(4) glutaraldehyde
(5) dyes
Benefits of embalming:
(1) inhibit decomposition of viscera, often for several years (for example, lungs may be preserved in the case of black lung disease)
(2) preserve tattoos or other identifying marks
Obstacles of embalming:
(1) mask or destroy drugs or toxins
(2) introduce chemicals that may be misidentified as toxins
(3) prevent culture of microorganisms
(4) laceration of internal viscera if a trocar is used
(5) removal of viscera
(6) introduction of air
In addition, the mortician may alter features or wounds to make them cosmetically acceptable.
Methods that may allow conclusions to be made:
(1) PCR or other molecular technique to identify microorganisms
(2) identifying of specific drug metabolites
(3) histologic examination of wounds