On August 6th, Cara Plese, M.S., Scientist I and Antonio Scatena, Laboratory Manager at Gateway Analytical hosted a webinar designed for police and attorneys on the topic of condom lubricant analysis. During this webinar, our presenters provided an in depth explanation of the analysis of condom lubricants and gave insight into many of the variables that can influence the results of a test, including appropriate collection time, the location of sampling, and the type of condom used in an assault. The presenters focused on the results of condom lubricant analysis and discuss what can be determined once a sample has been tested.
For more details on the webinar, you can use the links below.
We received a number of questions from attendees during the Q&A segment, and you can find those questions and answers below. If you have any questions about this or any other topic, please contact us.
- What is the most common lubricant you’ve encountered doing this type of analysis?
PDMS is the most common lubricant that will be encountered. In Coyle and Anwar’s study from our literature review, they site that 90% of the condom market in the UK uses PDMS. The majority of condoms in the US also use PDMS as the lubricant.
- You’ve addressed the ability to swab for condom lubricants in the oral and vaginal cavities, is it also possible to swab for condom lubricants in the anal cavity?
Yes, those swabs would be processed in the same way as we discussed in the webinar and we would be looking for the same components.
- How does this type of analysis provide benefits to a case over traditional DNA analysis?
Condom lubricant analysis should be used in conjunction with DNA analysis. Since DNA is unique to an individual, it will definitely be stronger evidence. One should definitely not forgo DNA analysis to do condom lubricant analysis, but instead, if there is not any DNA detected, it should be performed as a method to justify why there was not any DNA detected. Condom lubricant analysis is very valuable in the scenario where a victim is claiming to have been assaulted, but no DNA was recovered. Recovering traces of condom lubricants can indicate that an assault did occur, and it can explain why no DNA evidence was able to be recovered.
- How different are the lubricant formulas for condom companies?
Numerous companies use PDMS, PEG, and starches in their lubricants. Other components that may set one company apart from another are likely proprietary information. As of now, scientists have been largely unsuccessful at distinguishing between condom brand.
- Are the ratios of lubricants, particulates, spermicides, additional components so different that you could discern one brand from another?
As cited in Campbell and Gordon article, Analysis of Condom Lubricants for Forensic Casework, in the Journal of Forensic Science, even with using sensitive methods such as GC/MS, scientists have not been successful at distinguishing between condom brands.
- If DNA testing is done on a swab first are you still able to test for lubricants?
Yes, as long as a portion of the swab remains. We typically only take a portion of the swab to test, even if a whole swab is available.
- If an additional lubricating agent was used in addition to a condom, like KY Jelly, would this type of analysis be able to distinguish between the two?
Potentially, especially if the lubricant is available for comparison to what is recovered on a swab. Personal lubricants, such as KY Jelly, may be water soluble to mimic the natural lubricants in the body, and therefore they will not contain PDMS. Also, particles such as starches may not be present in additional lubricants used. If we can confirm that components not present in the additional lubricant are present on the swab, that is an indication that more than one lubricant may have been used.
- How you like to receive condoms in the lab and how do you like them packaged and persevered? Is there any difference if there is semen present inside or not?
We don’t necessarily need a whole condom. If there is semen inside the condom, it should definitely be submitted for DNA along with a swab from the external side of the condom. Condom lubricant analysis would also be able to be performed from just a swabbing of the external side of the condom to be compared to swabs from the victim.
- How do you consider the balance between potentially getting fingerprints from the condom and a profile from the outside or inside?
Typically, we just receive swabs as opposed to an entire condom. If we received a case where we knew fingerprinting was going to need to be performed, we would take efforts to swab as small of an area as possible so as not to disturb potential fingerprint evidence. Alternatively, the fingerprint analyst, or an investigator working with the fingerprint analyst could perform the swabbing in what was thought to be a “safe area” on the condom and keep it for further examination.
- What methods does your company use for submited forensic casework?
For condom lubricant analysis, we perform PLM and FTIR.