Submersion of cotton textiles in aquatic environments.

摘要

The contribution of clothing to death scene investigations is only beginning to be recognized. Forensic investigators have recently begun to undertake studies to document the degradation of clothing under different burial conditions; however, very few studies have examined the effects of aquatic interment. This study aims to develop a simple and inexpensive methodology to begin exploring this topic. Samples utilized deionized water or Mississippi river water in indoors and outdoors locations, and with and without an infant 100% cotton t-shirt. The levels of alkalinity, pH, water hardness, nitrates, nitrites, and water temperature of all samples were recorded in addition to atmospheric temperature and weather conditions. The study was carried out for 25 days (21 September 2012 -- 15 October 2012), observations of the physical appearance were made on 16 October 2012, and a more detailed examination of the shirts was performed on 5 July 2013. Nonparametric Wilcoxon paired t-tests were used to compare differences across data.;In general, samples with river water had significantly higher pH, alkalinity, and nitrite levels. Outdoors samples had significantly higher levels of alkalinity, pH, and water hardness. Significantly lower pH was documented in most samples which contained shirts, except for outdoors river samples, but all samples had a higher alkalinity when a shirt was present. Nitrite levels were less dependent on the presence of a shirt and more dependent on water type, with river water samples generally having higher nitrite levels throughout the study, and indoors samples having the highest nitrite levels. Over the 25 day period, temperature differences among samples were not significant, but significant differences between the atmospheric temperature and sample water temperatures were noted, with indoors samples having a significantly higher mean temperature than the air, and outdoors samples significantly lower mean temperatures than the atmospheric temperature. In future studies, alkalinity, pH, nitrites, nitrates and temperature should all be monitored when studying textiles in aquatic environments. As the purpose of this study was to potentially identify a simplified test protocol for determining the length of time clothing has been exposed to an aquatic environment, the easily sourced and cheaper equipment utilized were generally not as sensitive as may be needed, and may have affected the results and conclusions.