I know I've seen cases before where blood was found in a sink or drain. Can someone who has forensic knowledge tell me how you would test to find that? If Gannon was bleeding, coughed up blood, or vomited and tried to clean himself up would they have to remove the sink, bathtub, or shower stall base along with plumbing drain to test for blood or fluid?
How would they test a washing machine? Luminol, swabs?
I've seen forensics dismantle u bends and pipes.
I suppose the question is whether fabrics can be tested for blood following a machine wash.
Here's a brief synopsis of a recent paper
Quickenden and colleagues [8] investigated the effectiveness of Luminol for the detection of blood in cars after having been cleaned with water, soap, or multi-purpose car cleaner. They found out that washing decreased the detectability of blood up to 50% when warm water was applied and up to 90% when soap or car cleaner was used. Interestingly, they also discovered that the heat inside the car converted hemoglobin to methemoglobin, which increased the detectability of stains by the Luminol reaction. Grifford [9] conducted research about bloodstain preservation in water. He prepared his sample by depositing blood on pants and discovered that stains would not remain on clothing after 30 min in moving or 3 h in stagnant water. Thus, it is reasonable to expect that machine washing would probably remove blood even faster. This hypothesis was tested by Adair and Shaw [10]. Their study focused on the enhancement of bloodstains on washed clothing by Luminol and LCV (Leuco-crystal violet). Thereto, they covered white cotton undershirts with different bloodstains (using horse blood), both direct spatters (projected bloodstains and misting bloodstains), and contact bloodstains (footwear impressions). After drying for 1 h, the shirts were washed for one to five times in a washing machine with liquid laundry detergent. All shirts showed a significant diffusion of
Detectability of bloodstains after machine washing - ProQuest (it stopped there)
but I found another bit here
Bloodstains on textiles can provide useful information for the forensic reconstruction of a crime. Surprisingly, little is known about the applicability of bloodstain traces after a textile was machine washed. In this study, we investigated the effect of machine washing on bloodstains on both cotton and polyester cloths. The influence of the washing detergent, the type of washing machine, the washing temperature, and the duration of drying of the bloodstain prior to washing as well as the drying temperature was investigated. Additionally, the molecular analyses of a subsample of the experiments were conducted. We found that although the primary morphology of the traces is often blurred, the presence of blood on the textiles can still be detected in many cases. Blood can also be transmitted to previously blood-free textiles during the washing process, leading to a positive Luminol or Combur® reaction of these samples. When traces of blood can be detected via the Luminol reaction, a molecular identification of the blood donor was successful in 28% of the cases.
Detectability of bloodstains after machine washing
This 2017 article
... For example, DNA profiles from semen stains were found to still be retrievable after washing and also retrievable from other co-washed clothing as well as the washing machine drum [161,189]. Similarly, reportable and/or informative DNA profiles from blood tended to be obtained from washed blood-stained cloths and from co-washed clean cloths [190][191][192]. In contrast, van den Berge et al. [104] found that the average persistence rates of DNA from both blood and saliva-stained cloths after washing were less than 0.001%, and the transfer of DNA from these stains onto the co-washed items was found to be extremely limited with only a very few alleles, if any, being detected. ...
... Further studies have started to address the transfer and persistence of skin derived biological material on washed clothing. DNA deposited onto cotton cloths via rubbing on the neck for 5 s gave full DNA profiles from 40% of cloths held under a running tap (with cold or hot water at different time points up to 10 min) and 56% of cloths submerged in water in a bathtub (with or without soap and at different time points up to one week) [193], but gave only partial profiles from 13% of cloths that were machine washed [192]. Kamphausen et al. [192] observed few alleles, if any, on the remaining cloths that were machine washed and similarly few alleles were recovered from co-washed clean cloths. ...
https://www.researchgate.net/public...of_DNA_traces_between_textiles_in_the_washtub
Conclusion- it can actually be isolated from washing drum. A tad long winded but better hitting scholarly literature for accuracy.
Washing machines are large, just sayin'
