Preliminary investigations into the use of single metal deposition II (SMD II) to visualise latent fingermarks on polyethylene ‘zip-lock’ bags in Western Australia

Interpol review of fingermarks and other body impressions (2019 – 2022)

“…Colloidal gold – MMD I was recommended over black powder and [CA ➭ black gel lifter] to detect fingermarks on the inside of rubber gloves [ 363 ]. The following papers discussed the use of colloidal gold, but are detailed in other sections of this report: MMD I to detect fingermarks on fabrics [ 364 ] – See Section 4.4.3 ; MMD I to process plastic bags made of compostable polymers [ 365 ] – See Section 4.4.6 ; SMD II to detect fingermarks on PE zip-lock bags exposed to stagnant water and outdoor conditions [ 366 ] – See Section 4.5.2 .…”

“…PE zip-lock bags – D'Uva et al investigated the performance of SMD II and black powder dusting on PE zip-lock bags exposed to stagnant water and to outdoor weather [ 366 ]. The main conclusions were: (1) SMD II outperformed black powder dusting, being on marks unexposed to water as well as those exposed up to four weeks, (2) the quality of the fingermarks decreased with the length of the exposure to water, but SMD II maintained a non-negligible capacity to detect fingermarks after four weeks of exposure to adverse conditions, and (3) aqueous immersion using stagnant rain water led to larger detrimental impact compared to tap water, a likely explanation being the presence of contaminants and bacteria.…”

Investigating microplastics and nanoplastics released from food bag ziplock using SEM and Raman imaging

“…The zipper-like plastic fastener allows an easy closing (and opening) of the bags for a tight sealing. The sealing offers protection from moisture, heat and other atmospheric contaminants, which makes it a preferred choice for package, storage and transportation of food and household items [1,2]. Its market was estimated at US$ ∼21 billion in 2021-2022, and likely reach US$ ∼25 billion by 2032 [3].…”