Page 13 - Stained With Suspicion Blood Detection

There are many presumptive tests that can be used depending on the preference of the investigator, the
forensic lab, and the situation. Some of the tests used are listed in the table below.

PRESUMPTIVE INDICATION OF SITUATION
TEST POSITIVE USED REAGENTS FALSE POSITIVES

Reduced phenolphthalein Vegetable material
Phenolphthalein Bright pink color On visible (phenolpthalin), hydrogen (e.g. potatoes and
(Kastle-Meyer Test) stains
peroxide, in alkaline medium horseradish)
TMB, hydrogen peroxide,
On visible in acetic acid medium Oxidizing agents,
Tetramethylbenzidine Green to bluegreen color stains / TMB, diisopropylbenzene catalyst, and vegetable
(TMB) / Hemastix peroxidase Cosmetic
Field tests dihydroperoxide, buffering substance
material

Plant enzymes, oxidizing
Blue-white to yellowish Luminol, sodium carbonate,
Luminol Latent blood agents, metals, and
green light sodium perborate
chlorine
Latent blood,
Fluoresce with Reduced fluorenscein
Fluorescein vertical Copper, hypochlorite
alternate light source (fluorescin), hydrogen peroxide
surface

THE MYSTERY OF LYLE AND LOUISE 13