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A Reflective Spectroscopy Proof-of-Concept Study of Urea for Supporting Investigations of Human Waste in Multiple Forensic Contexts

NCJ Number
311428
Journal
Forensic Sciences Volume: 4 Issue: 3 Dated: 2024 Pages: 463-474
Date Published
September 2024
Length
11 pages
Abstract

Human urine and its detection are of interest in forensic studies in numerous contexts. Both crystalline urea and 1.0 M solutions of urea, as synthetic analog endmember components of human urine, were investigated as a proof-of-concept study to determine if detailed lab spectroscopy would be viable. Urea was reliably detected on Ottawa sand at concentrations of approximately 3.2% in dried experiments. Urea was detectable after 1 week of solution evaporation under lab conditions, at 9.65 wt.% 1 M solution. This investigation successfully establishes urea as a material of interest for reflective spectroscopy and hyperspectral remote sensing/image spectroscopy on a wide range of spatial scales, from specific centimeter-scale areas in a crime scene to searching large outdoor regions > 1 km2. In addition, this investigation is relevant to improving the monitoring of human trafficking, status and condition of refugee camps, and monitoring sewage.

(Publisher abstract provided.)

Date Published: September 1, 2024