Reply
Thread Tools Display Modes
#1
Old 01-30-2008, 12:38 AM
Charter Member
Join Date: Aug 2002
Location: Portland, Oregon
Posts: 1,775
Does semen show up under a black light?

A friend and I were indoors at a place...it was dark, but "black lit." He said the glowing spots on my t-shirt were semen stains. I say no way, I washed it.

What say you?
#2
Old 01-30-2008, 12:44 AM
Guest
Join Date: Nov 2004
Location: Left of spleen
Posts: 2,662
So...you haven't found the answer to this experimentally yet?

Pullet
*A girl*
#3
Old 01-30-2008, 12:44 AM
Charter Member
Join Date: Aug 2002
Location: Portland, Oregon
Posts: 1,775
Aaargh...took too long to edit...

It should read like this:

A friend and I were indoors at a place...it was dark, but "black lit." He said the glowing spots on my t-shirt were semen stains. I say no way; I washed it.

And that's the main question...does semen wash out of t-shirts after one typical wash in a washing machine?

What other (common) things might have caused the "blacklighted" stains?

Inquiring minds
#4
Old 01-30-2008, 12:46 AM
Charter Member
Join Date: Aug 2002
Location: Portland, Oregon
Posts: 1,775
Quote:
Originally Posted by Pullet
So...you haven't found the answer to this experimentally yet?

Pullet
*A girl*

I *would* but 1978 called and asked for my black light back

Seriously, though, if I had one I'd perform the test...all in the name of science
#5
Old 01-30-2008, 12:51 AM
Guest
Join Date: Nov 2004
Location: Left of spleen
Posts: 2,662
You can get a new blacklight for like $12 at Walmart.

It's all in the name of science! Do it!
#6
Old 01-30-2008, 12:52 AM
Charter Member
Join Date: Oct 2002
Location: N.J.
Posts: 5,133
Quote:
What other substances glow under a black light?

Urine, porphyrin, semen, sperm and saliva fluoresce under a blacklight.
http://ratbehavior.org/BlackLight.htm
#7
Old 01-30-2008, 12:57 AM
Charter Member
Join Date: Jun 1999
Location: Milwaukee, WI
Posts: 26,587
I'd like to reiterate something I've mentioned over and over. People always think all the stains on the comforter/tshirts/walls etc etc that glow under a black light are seman. Well, laundry detergent glows also. The stains on your tshirt or probably just left over laundry detergent.
#8
Old 01-30-2008, 01:01 AM
Charter Member
Moderator
Join Date: Jan 2000
Location: The Land of Cleves
Posts: 73,145
Almost any organic material will glow, to some extent, under a black light. The stains on your shirt could equally well have been drool, or food, or blood, or possibly sweat (I'm not sure about that one). You know better than we would how recently you would have been in contact with any of those substances.
__________________
Time travels in divers paces with divers persons.
--As You Like It, III:ii:328
Check out my dice in the Marketplace
#9
Old 01-30-2008, 01:16 AM
Guest
Join Date: Mar 2003
Location: Florida
Posts: 11,853
I heard club soda glows, too. Did you have something with club soda that you spilled on yourself? Was this a club that stamps your hand so you can get back in if you leave? Because they usually use a fluorescent ink and if you rubbed it on your shirt then it would glow. Highlighter ink also glows.
#10
Old 01-30-2008, 05:38 AM
Guest
Join Date: Nov 2002
Location: San Francisco, Ca
Posts: 1,731
I second the laundry detergent Idea.

Too lazy to find a cite right now, but I believe Modern Laundry detergent contains phosphorous to 'make your whites whiter and your colors brighter'. It shows up under a black light as glowing specks on your shirt.
#11
Old 01-30-2008, 05:53 AM
Guest
Join Date: Mar 2007
Location: Dublin, Ireland
Posts: 10,130
Also, jip stains are nearly impossible to get rid of.
#12
Old 01-30-2008, 07:41 AM
Guest
Join Date: Jan 2008
Location: Franfurt am Main, Germany
Posts: 125
A little off topic but I encountered a bathroom in a Dublin pub that was heavily black-lit, and urine certainly flouresces.
#13
Old 01-30-2008, 07:52 AM
Guest
Join Date: Apr 2001
Location: Wisconsin
Posts: 3,385
[Mitch Hedberg]
I was under the impression that that mustard stain came out.
[/MH]
#14
Old 01-30-2008, 09:05 AM
Guest
Join Date: Mar 2007
Location: Pittsburghish
Posts: 1,256
Many detergents contain additives that are UV active. They enhance the whiteness of your whites.
Without having actual experimental evidence, I'd wager that most *ahem* protein based stains should come out under normal washing conditions.
#15
Old 01-30-2008, 09:06 AM
Guest
Join Date: Feb 2003
Posts: 845
Do you have any reason to believe that they ARE semen stains on your shirt?
#16
Old 01-30-2008, 09:10 AM
Voodoo Adult (Slight Return)
Charter Member
Join Date: Jul 2000
Location: Charlotte, NC, USA
Posts: 24,875
Quote:
Originally Posted by flurb
Do you have any reason to believe that they ARE semen stains on your shirt?
I took the statement "No way, I washed it" as evidence to support a "yes" answer to that question.
#17
Old 01-30-2008, 09:23 AM
Member
Join Date: Aug 2001
Location: Bedrock
Posts: 26,079
Nevermind.

Last edited by lieu; 01-30-2008 at 09:28 AM.
#18
Old 01-30-2008, 09:36 AM
Guest
Join Date: Jul 2004
Location: Sweet Home Chicago
Posts: 33,496
Quote:
Originally Posted by Wile E
I heard club soda glows, too.
I don't think it's club soda, but tonic water that you're thinking of. The quinine in tonic water glows under black light. Club soda's just water and CO2, sometimes with salt or baking soda.
Quote:
Originally Posted by brewha
[Mitch Hedberg]
I was under the impression that that mustard stain came out.
[/MH]
[Once More, With Feeling]
♫They got
the mustard
OOOOOUUUUUUT!♫

♫(They got the mu-stard out!) ♫
[/Once More, With Feeling]

My vote is also for detergent. Sounds like you're packing your washing machine too full for a good rinse cycle, and it's leaving stuff behind.
#19
Old 01-30-2008, 11:23 AM
Guest
Join Date: Mar 1999
Location: underpants
Posts: 19,743
Maybe the cat is humping your laundry.
#20
Old 01-30-2008, 11:25 AM
Guest
Join Date: Nov 2001
Location: Akron, OH
Posts: 5,482
There was a nice Youtube video along these lines.
A young lady was at a party, dancing as you please... one of her girlfriends pulled her aside and she left.
The young lady had a bright spot spreading beneath her skirt... and glowing on the left side of her mouth...
#21
Old 01-30-2008, 11:37 AM
Voodoo Adult (Slight Return)
Charter Member
Join Date: Jul 2000
Location: Charlotte, NC, USA
Posts: 24,875
Quote:
Originally Posted by Mr. Slant
There was a nice Youtube video along these lines.
A young lady was at a party, dancing as you please... one of her girlfriends pulled her aside and she left.
The young lady had a bright spot spreading beneath her skirt... and glowing on the left side of her mouth...
There's also an episode of ER where Dr. Chen (IIRC) is found to have tell-tale stains on her sweater (IIRC). She's so dignified and indignant about the snickering, pointing out all the other things it could be, that you feel guilty about snickering along with the characters. Then at the end she throws the sweater (IIRC) away with the most guilt-ridden and ashamed expression on her face you can imagine, putting the lie to her proclamations.

It was actually very touching. And hawt, because you know ... Dr. Chen. Dirty hawt.

Last edited by KneadToKnow; 01-30-2008 at 11:38 AM.
#22
Old 01-30-2008, 11:45 AM
Charter Member
Join Date: Jun 1999
Location: Milwaukee, WI
Posts: 26,587
Quote:
Originally Posted by Mr. Slant
There was a nice Youtube video along these lines.
A young lady was at a party, dancing as you please... one of her girlfriends pulled her aside and she left.
The young lady had a bright spot spreading beneath her skirt... and glowing on the left side of her mouth...
Similar to this one
http://youtube.com/watch?v=H9md6x7JKnk
#23
Old 01-30-2008, 04:00 PM
Guest
Join Date: Feb 2000
Location: Montréal, Québec
Posts: 8,772
I agree with the suggestion that it is probably laundry detergent. You'd be surprised at how much organic stuff glows under UV/Black light; in fact, the fact that many things DO fluoresce is the basis for UV/Vis spectroscopy and the most common detectors for HPLC analyses. Entire fields of chemistry/entire analytical jobs rely upon the ability of things to glow under UV, down to the point of being able to tell different molecules apart based upon it!

My diamond from my engagement ring also fluoresces blue. Very pretty!
#24
Old 01-30-2008, 04:33 PM
Guest
Join Date: Dec 2005
Location: Van Nuys, CA
Posts: 11,663
Cigarettes look pretty cool under black light too.
#25
Old 01-30-2008, 06:04 PM
Charter Member
Join Date: Apr 2002
Location: Vegas, baby!
Posts: 3,641
Just to add a data point, I'll say: none of the black lights I've ever tried (four of them, from stores like Wal-Mart) have caused semen to visibly fluoresce at all. Lots of other stuff, including laundry detergent, but not semen. I always wondered if the CSI-types used some kind of special black light, or if it only glows very faintly and the purple glow from the light washes it out, or something.
#26
Old 01-30-2008, 06:25 PM
Voodoo Adult (Slight Return)
Charter Member
Join Date: Jul 2000
Location: Charlotte, NC, USA
Posts: 24,875
Quote:
Originally Posted by chorpler
Just to add a data point, I'll say: none of the black lights I've ever tried (four of them, from stores like Wal-Mart) have caused semen to visibly fluoresce at all. Lots of other stuff, including laundry detergent, but not semen. I always wondered if the CSI-types used some kind of special black light, or if it only glows very faintly and the purple glow from the light washes it out, or something.
The first time I ever heard of this forensics technique was in one of Patricia Cornwell's Kay Scarpetta novels. In that one, the light had a special name, but I don't remember it now. I'll check tomorrow at work if nobody beats me to it.
#27
Old 01-30-2008, 09:13 PM
Charter Member
Join Date: Aug 2002
Location: Portland, Oregon
Posts: 1,775
Quote:
Originally Posted by flurb
Do you have any reason to believe that they ARE semen stains on your shirt?
That stuff gets everywhere. It's worse than ice cream in a car.
#28
Old 01-31-2008, 12:04 AM
Guest
Join Date: Nov 2000
Location: Olympia, Washington
Posts: 5,632
I'm going to chime in here, as somebody who has been carrying around a UV-light keychain for the better part of a year: yes, it does, but so do a ton of other things, including:

Coca-Cola
white paper
some detergents
some antibacterial soaps
some Chap Stik
motor oil
antifreeze
bacteria scum in the sink

...the list goes on. Try a black light and see!
#29
Old 01-31-2008, 02:05 AM
Guest
Join Date: Jul 2001
Location: NY
Posts: 478
OK some real experimental data: I tested it and it didn't glow under fluorescent black lights, either fresh or dried. However, I'd wager that the UV lights they presumably use for crime scenes probably utilize the more dangerous, cancer-causing UV wavelengths, which would be forbidden for general use in bars, etc, due to the fact that they easily cause sunburn, cataracts, and damage DNA.

Oh, and laundry detergents definitely glow very strongly.
#30
Old 01-31-2008, 03:20 AM
Guest
Join Date: Jul 2002
Location: UK
Posts: 4,893
This would indicate that the appropriate wavelengths are not even UV

Crime-lite
Quote:
* Violet Crime-lite® with a wavelength peak of 425nm (10% bandwidth
400-430nm) for detecting blood stains and gunshot residues.
* Blue Crime-lite® with a wavelength peak of 450nm (10% bandwidth
430-470nm) for general search for body fluids.
* Blue/Green Crime-lite® with a wavelength peak of 485nm (10% bandwidth
460-510nm) for treated superglue fingerprints.
* Green Crime-lite® with a wavelength peak of 520nm (10% bandwidth
500-550nm) for DFO treated fingerprints.
The orange goggles/filters just increase contrast for the fluorescence.

Although longwave UV also seem to be used for forensic lights.

Si
#31
Old 01-31-2008, 06:46 AM
Guest
Join Date: May 2003
Location: Southampton
Posts: 1,003
LSD fluoresces under a black light.........
#32
Old 01-31-2008, 11:08 AM
Guest
Join Date: Nov 2003
Posts: 1,735
Quote:
Originally Posted by WILLASS
LSD fluoresces under a black light.........
It also makes the wallpaper inhale and exhale.
#33
Old 01-31-2008, 11:50 AM
Guest
Join Date: Aug 2001
Location: Ass end of Alberta
Posts: 17,897
Quote:
Originally Posted by WILLASS
LSD fluoresces under a black light.........
So does coffee.

Back in the eighties and nineties, when I sometimes found myself in blacklit situations where LSD was being used, I used to amuse myself by using a q-tip to apply cryptic symbols to my face in coffee. Dries invisible, and then later, under black light, you trip the hell out of your fellow heads.

Good times.
#34
Old 01-31-2008, 01:04 PM
Guest
Join Date: Mar 1999
Location: underpants
Posts: 19,743
Quote:
Originally Posted by MaceMan
OK some real experimental data: I tested it and it didn't glow under fluorescent black lights, either fresh or dried.
How about pan-fried?
#35
Old 01-31-2008, 02:35 PM
Guest
Join Date: Nov 2004
Location: Left of spleen
Posts: 2,662
Quote:
Originally Posted by KneadToKnow
The first time I ever heard of this forensics technique was in one of Patricia Cornwell's Kay Scarpetta novels. In that one, the light had a special name, but I don't remember it now. I'll check tomorrow at work if nobody beats me to it.
Are you thinking of a Wood's lamp?
#36
Old 01-31-2008, 03:46 PM
Voodoo Adult (Slight Return)
Charter Member
Join Date: Jul 2000
Location: Charlotte, NC, USA
Posts: 24,875
Quote:
Originally Posted by Pullet
Are you thinking of a Wood's lamp?
At this point in my day, it will be Saturday before I can verify with the text itself, but that sounds very, very, very right.
#37
Old 01-31-2008, 03:59 PM
Moderator
Moderator
Join Date: Dec 2003
Location: Detroit
Posts: 9,490
http://labino.com/pdf/Crime%20-%...y%20fluids.pdf

Page 2 shows examples of semen stains under UV light.

And see: http://abcnews.go.com/GMA/Health/story?id=1507794

Last edited by Gfactor; 01-31-2008 at 04:00 PM.
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 09:53 PM.

Copyright © 2017
Best Topics: bookworm games lol feline clavamox canned chili medival drawings puffy butthole straight guys experimenting simpsons boot bactrim ds alcohol brown lettuce 1950s background music deadliest catch scripted poland black death bijou drains jumbo eggs fried turkey giblets pup babylon young poets collection temporary website hosting broham definition infrasound ghost eat your wheaties coke lite 7mm allen wrench philson ahn 2 stroke supercharger paramax audio mrs cintron snow blowing adirondack pronunciation viagra priapism counterfeit stamp nun hats drive thru etiquette left arm hurts when i sneeze lemmy i ain't no nice guy sanding drywall without dust use speaker wire for power get cat to gain weight weight loss contest names teachers and students dating dialing 1 before area code a correlation demonstrates a cause of behavior. automatic fails on driving test california average gpm for a well sell a mink coat guy passes out from dab purple shirt with blue jeans oil based paint for bathroom surgical tubing for slingshot alternative to bose wave music system getting pregnant 2 months after c section reading glasses for laying on your side how long to trickle charge a 12 volt battery how does dick taste teeth drifting after extraction why won't pizza hut deliver to me my milkshake brings all the boys to the yard meaning schlage keys cut to code foods that begin with e .577 t-rex vs 50 bmg why do dogs sit on each other how do land surveys work how to make pigeon poison how to dress for a part time job interview why wont my debit card work on ebay how to remove lamination from social security card how to clean an afghan blanket can you keep bats as pets gfci reset won't stay in when pushed