Evaluation of lugol’s iodine as a screening tool for identification of dried saliva stains

Abstract

The evidential value of saliva in stains encountered in crime investigations can be of considerable importance. Whether the stains are a result of expectoration or a consequence of some sexual or violent act resulting in saliva being mixed with other body fluids, the investigating forensic expert is faced with two fundamental problems: localization of stain and visualization of stain. Visualization of saliva is problematic unlike other body fluids like blood which has its own internal marker (i.e., hemoglobin) or semen that can be easily identified by acid phosphatase method.: Evaluate of lugol’s Iodine as an easy, chair side screening tool for identification of saliva from the crime scene. In the present study saliva stains on different fabrics viz. silk, polyester, linen, jute, cotton, georgette, sarton and other items like paper cups, chocolate wrapper aluminium, plastic bags, stainless steel spoon (cutlery) were examined using Lugol’s iodine. Lugol’s Iodine test was found to give Positive results for saliva stains on different fabrics and it was also found that the stains on different fabrics gives positive results for saliva even after washing with water, but none of the fabrics gave positive results for saliva after washing with detergents and alcohol.From the above study it is concluded that Saliva is retained in fabrics even after washing with water. Detergents fades off the color of stain and alcohol darkens the colour of stain from study items.