Persistence of Polydimethylsiloxane Condom Lubricants

Area of Science:

• Forensic Science
• Toxicology
• Biomaterials

Background:

• Polydimethylsiloxane (PDMS) is a common lubricant in condoms.
• PDMS detection on complainants can support sexual assault allegations.
• Prior research focused on analytical methods for PDMS detection.

Purpose of the Study:

• To determine the persistence of PDMS on human tissues and skin.
• To evaluate the impact of biological fluids and post-exposure activities on PDMS detection.
• To assess the compatibility of PDMS analysis with DNA extraction procedures.

Main Methods:

• PDMS application to various body sites (penis, vagina, mouth, skin).
• Sample collection via swabs at timed intervals.
• Analysis of PDMS presence using established analytical techniques.
• Assessment of PDMS stability in the presence of biological fluids and after standard DNA swab processing.

Main Results:

• PDMS detection times: up to 20 hours on the penis, 35 hours in the vagina, and 52 hours on skin.
• Oral PDMS detection: up to 4 hours without food/drink, up to 9 hours during sleep; not detected after eating/drinking.
• Biological fluids did not negatively impact PDMS analysis.
• Aqueous DNA extraction did not significantly remove PDMS from swabs.

Conclusions:

• PDMS exhibits significant persistence on various body surfaces, particularly skin and within the vagina.
• Oral PDMS detection is transient and affected by food and drink consumption.
• PDMS analysis is feasible even after standard DNA swab processing, offering a dual-purpose forensic tool.