Examination of Firearms Review: 2007 to 2010 - Interpol

found between the fingermark donation status and the DNA shedder status. The level
of ridge details on a fingermark is consequently not correlated with the subsequent
DNA profiling tests.
2.2.14 CBRNE-related evidence (Chemical, Biological, Radiological, Nuclear, and
Explosive)
Research on CBRNE-contaminated evidence has seriously increased
during these last three years. Most of the researches were dedicated to
the effect of the contaminant, and of the decontamination procedures, on
the subsequent detection of latent fingermarks. In the case of chemical
contamination, if items were contaminated with acid chemical vapours, the
use of volatile organic bases could help in improving the cyanoacrylate
fuming process (314). In the case of biological contamination, the use of
formaldehyde vapours during the decontamination procedure could be
detrimental for some amino-acid reagents (315). No adverse effects were
however observed if irradiation is used to decontaminate the items (316).
Finally, bacterial activity showed almost no detrimental effect on the latent
and blood fingermarks left on porous and non-porous substrates
(variations were however obtained for adhesives) (317). In the case of
irradiation, fingermarks could still be detected on glass and aluminium
after high doses of irradiation (even if glass could become optically
degraded) (318). However, detrimental effects induced to the substrate
itself (especially for plastic and paper items) could hamper the fingermark
detection processing. Nevertheless, up to 100 kGy, it has been shown that
the processing of latent fingermarks using common detection techniques
is still possible. In another study, some chemical and physical
decontamination procedures were shown to be highly detrimental on the
subsequent recovery of latent fingermarks on documents (319). In such
cases, it is either recommended not to decontaminate the documents
(even after the recovery of fingermarks), or to proceed to the
decontamination after the recovery of fingermarks. Explosive
contaminations could be located and identified on latent fingermarks using
analytical tools such as Raman chemical imaging (320), or Fourier
transform infrared spectroscopy (321, 322). Fingermarks on post-blast
devices could still be detected using either cyanoacrylate fuming (323), or
reflected UV imaging (RUVIS) (324).
Chemical contamination
The exposure of evidence to hydrochloric acid (HCl) vapours or chlorine (from a
chemical weapon or from methamphetamine laboratories) could result in an
acidification of the secretion residue, causing detrimental effects on some fingermark
detection mechanisms (such as cyanoacrylate polymerization or ninhydrin).
McDonald et al. assessed the efficiency of a basic pretreatment (using volatile bases)
prior to the application of detection techniques (314). Fingermarks on glass slides
and standard photocopy paper were considered. They observed that exposure to
high level of acid vapors could indeed lead to an inhibition of the cyanoacrylate
polymerization and to a modification of the ninhydrin reaction mechanism (leading to
light pink-red marks instead of dark purple). Exposure of the evidence to
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