Hi Kelly that is an interesting question - and to be honest I do not know the answer.

I performed a quick search on-line and the only reference to de-pigmentation I could find was in this link:

http://ntp.niehs.nih.gov/testing/status/chemid/hsdb-50-00-0.html

Under the section "LABORATORY ANIMALS" it states: "Acute Exposure: Hair depigmentation was observed in black mice at site of sc injection of 100 ug formaldehyde"

So I guess from what is mentioned in the link it seems this might be possible. I am quite tempted to take some dark hair and expose it to formaldehyde and see if it bleaches (although I don't think I'll wait 187 years for the answer).

If Alves had any living relatives the tissue could be examined and the DNA profile  compared to them.....

Sorry I can't be more help!

Gary

I was working with a corpses in formaldehyde a bit, they all very bleached, having grey appearance, and if you like, there is somewhere the video about Lenin, and actually when they exposed him out from the bath, without make up etc, his hairs are grey.

Dagmara that is very interesting - did you also notice if the eyes of the corpses became depigmented? That for me is the most surprising thing (if true). Once again I am tempted to get some eyes and try it (cow eyes that is)...

Cow eyes will already de-pigment  while in the fridge, especially will "cloud up" making grey- blue appearance. Yes I did observe heavy de-pigmentation , Gary, and its very quick. The oldest corpses i saw i think was + 20 years, formaldehyde and second one dried (Ukraine), dried was black in color and strain like appearance of tissues, where from formalin was "wash out", grayish, bluish, very pale, the deceased was normally in old age, but surprisingly(?) all corpses always had white/ grey hair. 

Dagmara and Gary, both of your responses help a lot! Thank you so much for the link and for engaging with me on this topic.

I've never dealt with human tissue.  However, I've found that almost any animal (from worms to vertebrates) loses pigment colors (as opposed to structural colors) with time in formaldehyde.  In most cases it doesn't seem to take very long (often less than a year).  I've also noticed that the eyes of many animals seem to turn bluish.  Don't have any references for you, just seems to be a common phenomenon.

Thanks, Jeff. I appreciate your input. When I saw the head in the jar, his eyes had definitely faded to a bluish color. I've dug around a little more and it seems like this phenomenon is pretty consistent across all tissue samples, so I'm going with to run with it in the article. This thread, and site, has been a great help to me! Thanks again to everyone who has helped out with my science question!! If you have grammar questions, you know I'm here for you.

Hi,

Read this article, it helps a lot and will clear up the relationship between menlocytes and chemicals.

The link is: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2084341/

Thank you

Dr.Mohsen

Thank you, Dr. Mohsen!

Hair can undergo an equivalent process in formaldehyde as what you would expect from 'peroxide bleaching' in human hair, just not as quickly or to the same extent. It undergoes an oxidation/alkaline reaction as it breaks down from formaldehyde into formic acid.

I have no experience with human hair but hairs on feet of red, fallow, and muntjac deer, fixed for several  decades in 10% formalin do not appear to have changed colour. .

From my internship in a pathology museum such discolouration and bleaching is quite common. Human hair will also bleach with exposure to sunlight over time. As for eyes, eyes typically do not preserve well with older methods and considering the age of the specimen discolouration would be likely.

Due to the very long exposure in formalin/formaldehyde solution such tissue discolouration may be explicable. Nevertheless, I did never see such changes in specimens which were exposed to such solutions for up to 15 years.

All right, your or above researchers familiarity is exact and in adding together asthma / respiratory, skin, eye vision etc. If long term exposure/ high dose etc.