Sciencemadness Discussion Board

Paraformaldehyde mildewcide safety

GammaFunction - 9-8-2013 at 13:58

Maybe this isn't a question for this forum, but this is probably the only place to get a rational science-based answer rather than old wive's tales.

I have a mold problem because of humidity. I'm using calcium chloride in my closet, but it's not enough. My shoes get fuzzy. Outside of my closet, my precious microscope gets fuzz around the eyepiece, and wherever a person has touched it. I shudder to think about what's happening with the balsam in the optics. My nice binoculars got spots on the lenses.

I caved in and bought some Paraformaldehyde 91% mildewcide, as 60g satchels to place in my closets. But formaldehyde is toxic and carcinogenic, with as little as 0.05 ppm causing irritation and 0.3ppm being the maximum permitted workplace value.

Some rough math: a satchel might last 1 year, my closet is 6 cubic meters (6 kg of air), and air in the closet might be replaced once per day, so the average concentration could be (60 g/yr)/(6m3/day x 1000 g/m3 x 365 days/yr)=0.000027=27 ppm, about 90 times the workplace limit. That makes sense: it has to kill mold.

How is this stuff even legal?

I guess I have to put my shoes in a sealed box with it. And my optical valuables too, or put them under a bell jar. But at that point, why not use a desiccant (once the mildew is killed)?

Does anyone know of a safer chemical to kill mold, particularly one that exists in vapor form?

edit: candidate for another safer substance - Thymol. Used as a fungicide, and to kill mold on books. Maybe putting some under microscope covers would work. Also a possible carcinogen, but less than formaldehyde.

[Edited on 10-8-2013 by GammaFunction]

smaerd - 9-8-2013 at 18:28

If it is 'cob-web' mold a spray bottle of dilute hydrogen peroxide makes quick work of it.

You may want to try to find the source of the mold itself and try a chemical eradication or removal and replacement. Mold is bad stuff, not good for your health or belongings in general! Dehumidifiers work better then desiccant. In the long run a small dehumidifier isn't much more expensive either.

Make sure you're laundry isn't damp when you are putting it in. It's might not be a bad idea to do a deep cycle rinse and a sanitize run with the clothes washer and dryer on basically everything.

[Edited on 10-8-2013 by smaerd]

S.C. Wack - 9-8-2013 at 22:02

Quote: Originally posted by GammaFunction  
How is this stuff even legal?


www.epa.gov/oppsrrd1/REDs/formaldehyde-red.pdf‎

So...you want it illegal? I wish Sun Pac was sold here. The problem is, you apparently live in the southeast...mold isn't very aggressive over here...formaldehyde is apparently what it takes; toxic material with appreciable vapor pressure sounds just like what you need.

GammaFunction - 10-8-2013 at 03:38

Quote: Originally posted by S.C. Wack  

www.epa.gov/oppsrrd1/REDs/formaldehyde-red.pdf‎



Great source. Thanks. So this stuff is meant for unoccupied houses, and closed drawers.

If you want it, it can be ordered over internet.

I just hope the mold gets a worse case of cancer than I do.

GammaFunction - 10-8-2013 at 12:18

Quote: Originally posted by smaerd  
If it is 'cob-web' mold a spray bottle of dilute hydrogen peroxide makes quick work of it.
[Edited on 10-8-2013 by smaerd]


The problem is that, with items like shoes, the mold is not necessarily superficial, and the filaments may extend into the leather. So a gas like formaldehyde vapor can kill the mild inside the leather, while a superficial treatment cannot.

And with optics, the mold can can exist inside the casing.

Adas - 10-8-2013 at 23:41

Ozone would be my choice