Does Bleach Kill Mold?
(Feb. 8, 2012). I’m confused, first I read that bleach is not to be used for
mold , then I read that its good for non porous surfaces?
ANYTHING can remove mold from a non-porous surface (like a counter top or
tiled surface)---anything includes plain soap and water or bleach. It is
mold growing on porous surfaces like drywall, wood, carpeting, padding, etc.
that is the mold cleaning and mold removing challenge. Bleach is very
ineffective in killing mold for the many reasons explained in detail at the
bleach education website
http://www.bleach-mold-myth.com. For effectiveness in killing and
removing mold, consider using one of these two non-toxic sodium borate
product: (1) EPA-fungicide-registered
Tim-Bor (hard to buy without a pesticide operator license) or (2)
boric acid powder (readily available with a license from several
internet businesses including http://www.moldmart.net.
Another category of effective mold-killers is the ammonium chloride family.
Most EPA-registered fungicides like contain one or more chemical members of
the ammonium chloride family. The strongest mold killer in the ammonium
family is benzylkonium chloride.
Be trained and certified as a Professional
Industrial Hygienist and receive extensive on-the-job
training during your
industrial hygienist training from
Phillip Fry and Divine Montero.
Bleach Mold Myth
Ineffective to Kill Mold on Porous Surfaces (Most Building Materials)
Below are actual reports from bleach
users worldwide about the failure of bleach to kill mold growth,
as reported to mold victims to
consultant Phillip Fry.
---"I live in a half double and I recently discovered mold in my
home. In my downstairs living room and in my upstairs bedroom. I cleaned the area with
bleach and within a few days the white hairs were growing back."---D.W. on Nov. 17, 2004.
---"I can forward you
pics of the walls, which by the way I scrubbed with a bleach mixture, then sealed & repainted,
the black & fuzzy grey mold is growing back. I know it is the mold making me sick, I never
suffered from any of this before in my life."---R.K. on Nov. 21, 2004.
---"Mold grows all over the baseboards of the downstairs. In the
closets and on all the contents in the closets. It grows on the sofas and the pillows on the
sofas. It actually grows on any and everything down stairs. I have cleaned everything with
lysol and bleach and yet it returns."---K. in Tennessee on Nov. 22, 2004.
---"My air conditioner was leaking this
summer and caused water to run down my apt. wall, I now have mold on the wall, carpet, and
surrounding woodwork despite trying to treat it with bleach."---D.M. on Nov. 23, 2004.
---"My mother called the landlord and told him that there was
brown stuff growing on the walls, and he said clean it with bleach and water. My mother
is constantly cleaning the walls with bleach because it keeps coming back."---J.O. on Nov. 24,
---"The apartment manager sent a maintenance
man up and he wiped off it off with bleach. Well, it keeps coming back, just
noticed that in our bedroom where we all sleep mold started develop on the walls near the
floor."---L.D. on Nov. 29, 2004
---"We tried bleach on the
mold in our bathroom, but other than emit a nasty smell throughout the condo, it did
nothing."---E.T, Florida on Dec. 1, 2004.
every single window seal in my house, we have mold that appears every week. I have been
cleaning it off with bleach, but I want to know how to make it stop. All the windows are only
2-3 years old."---A.M., on Dec. 5, 2004.
---"Bleach works for a while but the mold keeps coming back." D.W.
on Dec. 8, 2004, from eastern North Carolina.
---"There was also mold growing on the walls behind my mirrors.
This has been noted to my land lord. The landlord's maintenance employees sprayed it with
bleach, and now the mold is back . My family's health has not been the best from living with
mold."--G.S., on Dec. 10, 2004.
---"We have used
clorox and Kilz on the growing mold on wall and baseboards and windows, but it keeps coming
Bleach and Kilz don't help stop mold."---H.M., on December 10, 2004
is mold growing on my basement walls a little at a time. I always wipe it off with bleach but
it eventually grows back (the walls are dry wall)."---D.M., on December 11, 2004.
had a lot of mold on my walls. It probably was about 20 inches high from base board. I always
cleaned it with bleach and it took it off for a while but always came back."---B.N., on Dec.
---"A month ago the apartment maintenance men cleaned the mold on
the wall by our daughters crib with bleach. Since then, we have found, 4 more spots of
mold, on the same wall."---K.O., on Dec. 29, 2004.
---"I have a really gross
looking mold (I think it’s a mold) growing in the corner of my shower, I believe originating
from the tile grout. It looks like two pale yellow macaroni noodles stuck together. They are
hollow and about 1 inch each. They appeared literally overnight, for the second time,
despite heavy cleaning and bleaching."---M.S., Los Angeles, California, on Dec. 29, 2004.
am 7 months pregnant and also have a 2 year old son and all of us have seemed to be sick since
we moved here. The manager has only wiped the mold away with bleach and told us to do so also
if it comes back..... which I have been doing every 3-5 days, that’s how long it usually takes
to reappear."---R.C., on Jan. 3, 2005
scrubbed several times with straight bleach and the mold just keeps returning."---D.D., on
Jan. 4, 2005.
have a severe mold problem growing in the basement. We have washed the walls time and time
again with bleach and water, but it never seems to do any good."---S.P., on Jan. 5, 2005.
---"I have tons of mold in my classroom. During the summer,
I scraped it off, bleached it, and painted it. It grew back within 3 days."---C.B. on
January 5, 2005.
---"We soon noticed one of the climbing vine houseplants had a
fluffy white mold growing atop it's "climbing pole." We've noticed that the surface of some of
the bricks were covered with a white powder, and unfortunately doused the bricks with bleach
after removing the plants. This caused a fluffy white overgrowth that was much worse than the
first."---R.L. on January 5, 2005.
---"We have a window mold problem. We have cleaned the tracks with
bleach and it comes back."---K.S. on Jan. 6, 2005.
---"Bleach seems to help control the mold only for a month or
so."---P.R., on Jan. 7, 2005.
---"The landlord recommended bleach which didn't get rid of the
mold---it's growing back."---A.M. on Jan. 11, 2005.
---"I have been bleaching the mold and scrubbing the effected
areas (the entire attic!) on a daily basis. But it keeps coming back."
---R.B. on Jan. 12, 2005
---"The mold spread over time and my wife tried to clean it with
bleach having no success."---J.A., on Jan. 12, 2005.
---"There is black mold in the shower at all
times. I bleach it and it goes away for a day or so and then reappears."---C.H. on Jan. 12,
---"I occasionally spray
the moldy basement cement walls with clorox bleach. The clorox only seems to work for a
month or two."--- A.B. on Jan. 13, 2005
---"I have mold
in my bathroom (ceiling and upper wall) and have tried bleach water and repainted with Kilz.
The mold is returning."
--- T.L. on Jan. 13, 2005.
walls are covered pretty much floor to ceiling along with the ceiling. Like many others, I
have cleaned with bleach only to have the mold return."---D.C. on Jan. 14, 2005.
with bleach but there is still mold in the house. I have been very nauseus and throwing up
every morning."---L.O. on
Jan. 14, 2005
spray will take it away but the mold comes back."---T.T. on Jan. 14, 2005.
---"A black powdery mold, growing in circle clusters keeps growing
and growing. bleach doesn't work. I want to be able to kill it for good."---K.M.
on Jan. 15, 2005.
who is a nurse and here on vacation, came over to our apartment and freaked out, saying that
she smelled and detected mold in our window ledges, after I had just bleached it less than a
month ago. So the mold has grown back since then."--M.P. on Jan.16, 2005.
---"On the front porch of my daughter's home, there was mold all
over. She cleaned with bleach and it came back."---A.C. in North Carolina on Jan. 16, 2005.
the building there are now several areas as large as 2 to 3 feet in diameter of what appears
to be a white mold substance coming up through the concrete. This substance cakes up 2 to 3
inches high. My rental manager has tried treating this with bleach and it has not stopped it
from re-occurring."---J.C. on Jan. 17, 2005.
---"My cement garage floor (1st time
ever) has white fuzzy mold all over it. First I washed it with diluted bleach, the next
day it came back. I just poured straight bleach on it but it still is coming back."---S.H.
in California on Jan. 18, 2005.
---"I have plaster walls throughout the
home, and have been cleaning the mold with vinegar, bleach and water -- the mold seems to
disappear, but within weeks it is back again." T.L. in Canada on Jan. 18, 2005.
tried the bleach method, and it didn't work."---H.B. on Jan. 25, 2005.
---The maintenance man comes and cleans the
mold off with bleach water, but as of yet nothing is being done to fix this 'growing'
---L.C. on Jan. 29, 2004.
---"I have tried bleach and the
mold killers from Home Depot. I sealed the moldy walls with a deep penetrating oil primer on
the cinder blocks after using the mold killer...None of these things have stopped the
mold."---S.H. on Feb. 3, 2005.
maintenance men for my building were the ones who pointed it out to me as mold. They did this
in December,. 2003. They said to treat the mold with bleach and I did but it keeps coming
back."---J.L. in Massachusetts on Feb. 3, 2005.
---"We are able to completely remove the
black spots when we clean the ceiling with Lysol Bathroom Cleaner (with bleach) but it’s only
a matter of a week or two before it’s back again."---K.O. on Feb. 4, 2005.
---"I tried bleach and wire brush. It looked fairly well but after 24 hours
the mold on the front wall is starting to grow back."---J.K. on Feb. 4, 2005
---"I spray the wood walls with bleach, but as I
have learned via the web, bleach is a myth. Please give me some advice as to how I can
kill mold effectively. It is such a shame to live in Hawaii and have to spend my days cleaning
mold off the inside walls."---D.K. in Hawaii on Feb. 7, 2005.
to notice mold growing on the window casings and the window sills. I would wipe it down with
bleach water, but it soon would return."---A.S. on February 8, 2005
tried to kill the mold in my house with bleach but it didn't seem to help at all."---J.D. on
Feb. 14, 2005.
husband washed the walls and windows with bleach (which obviously doesn't work because the
mold is of course growing back
now)."---D.L. in Florida on Feb. 15, 2005.
have cleaned the wall mold up with diluted bleach, but it has returned worse."--J.P. on Feb.
have a tenant that has a problem with grey mold in one room, They would bleach and then
the next day its back."---B.W. on
Feb. 17, 2005
need to know how to remove mold from the outside of my house. I have used bleach and Kilz and
it keeps returning every year."--E.H. on Feb. 22, 2005.
i noticed the mold, I washed it off with bleach. I also used a product called 'stopz'--- its
an oil based paint which stops stains from bleeding though the paint. I painted the wall about
the first week of Nov and I though that the bleach would get rid of the mold. About 3 weeks
later it came back even blacker and fuller than before."---L.F. on March 1, 2005.
---"We are finding mold all
over our house. Is it safe to live here? We have just finally decided to check into it,
because most of us are sick with many of the mold symptoms. I have cleaned it when it has
popped up with bleach, but it seems to be getting worse."---C.B. on March 2, 2005.
black and repeatedly grows back after being sprayed every few months with bleach."---E.K. on
March 5, 2005
am very concerned about this mildew that I have in my apartment. Almost every week I
clean it off with bleach and hot water and it still returns."---N.B. on March 12, 2005.
have have an ongoing problem with all of our outside walls getting black I don’t have a
picture but I can describe it as being like black soot I clean the walls with bleach but it
returns."---C.B.on March 12, 2005.
---"I live in an apartment and
my bedroom wall consistently grows mildew the owner tells me to clean it off with bleach but
it continues to grows. Of course I called and complained finally they sent out a painter to
spray paint over the walls and guess what the mildew came back!"---C.A. on March 15, 2005
---"We have tried bleach water
and it temporarily removes some of the mold but it grows back."---J.J. on March 21, 2005
started seeing MOLD little black/Brown patches in my shower...looks like it was also
underneath the tile caulking!! like the landlord was trying to cover it up!!!! I
scrubbed with bleach and sprayed Lysol ... it was back with in a week..."---S.S. on March 26,
---"In my room I have black mold that grows about six inches up
some of the walls. We bleach it and we have painted over it but it always returns."---D.P. on
March 30, 2005
live in the
Sacramento area of California and I have a problem with mold growing on the outside of my
home. Last year I talked to
the paint company (Sherwin Williams) that supplied the paint for our homes and they said use a
bleach water solution to get rid of the mold. I washed by hand last year about 1/3 of my home
with this bleach/water solution. This year it is back bigger than ever. I would have to wash
2/3's to 4/5’s on my home now."---S.H., Sacramento, California, on April 13, 2005.
cleaned the mold with Clorox and a toothbrush. Within 3 days, the mold reappeared about 4
inches away, I did the same thing and it reappeared about 3 days later."--K.N. on April 17,
year we have a black mold returning on the siding in all areas---North-South-East-and West
sides. We have washed it with bleach and then re stained. But that didn't
work."---A.K. on April 17, 2005.
---"We would spray bleach on
the mold and every other day it would grow back."---L.M. on April 17, 2005.
---"I found some mold in a
corner about 2 months ago and the maintenance man told me to clean it with bleach water so i
did but it came back worse."---C.S. on May 1, 2005
---- "No matter how much bleach I use, it keeps coming back," ---
S.B. on May 18, 2005
some black mold on the ceiling of my carport. It is a
open one facing the west side. What's the best way to get rid of it? I
have tried bleach that did not work. I bough a special paint, but the mold
came back.''---J.V. on May 30, 2005
--"I have a little black mildew and a bit of white fuzzy mold in my
basement. The white stuff has broken right through the Kilz paint that
was applied after cleaning with bleach."---L.H. on June 14, 2005
white and tan fungi (not mold) on the joists and flooring under the
house, possibly Serpula lacrimans, which we sprayed with full
strength household bleach last year before closing the place up. I had
also placed a layer of clear plastic sheeting over the entire crawlspace
sand floor. Of course this was a huge mistake because the water
component of the bleach was standing in puddles over the whole plastic
liner when we opened the place up this year, and the encrustation by
fungi is way worse."---B.M. [Michigan] on August 17, 2005.
---"About a month ago I noticed mold growing inside a kitchen cupboard and on
the surrounding drawers , I took everything out and cleaned the mold with a bleach
mix, (which I have no read might not have been a good idea), dried everything,
and left the cupboard open for a week. The mold is now back."---L.K. on August
---"I was under the
impression that bleach was supposed to kill mold, so we cleaned the bottoms of
all the furniture with bleach that was slightly diluted with water. I thought
that would kill the mold and keep it from coming back, at least for a while.
Apparently not, because its back again."
---D.K. on August 23, 2005.
---"I have tried to clean some wood paneling in a basement. Mold seems to
grow back in a couple of days. I cleaned it with straight bleach. I
have also tried polish and Mop and Glow floor cleaner. It seems to come
back every time." ---R.G. on August 30, 2005
---"There is a huge mold problem in the bathroom and in September of 2004 the
owner brought over some sort of bleach solution. After using the solution for
almost a year the mold continues to come back. I use the solution at least once
every three weeks and the mold seems to be getting worse."---T.S. on Sept. 3,
---"Mould is present on my furniture (mainly on the wooden furniture) caused by
the flat where I live being damp. I have tried to remove it with warm water and
bleach and have purchased a dehumidifier to combat the damp but it keeps coming
back."---C.B. in the United Kingdom on Sept. 3, 2005.
maintenance guy came with a small bucket of bleach. When he took the cabinets
off the wall, I looked up into the wall. The patch of black mold went all the
way up into the second floor. I was extremely skeptical that he could fix this
with a bucket of bleach, but he *insisted* he could. Well, of course, the mold
is back, worse than ever. It has invaded the a/c ducts (you can see it), the
kitchen, and both bathrooms."---J.D. on Sept. 4, 2005
Chlorine Bleach is ineffective in killing mold for
It is too diluted and thus too weak to permanently kill mold unless
the mold is simply sitting on top of a hard surface like a counter top
What little killing power chlorine bleach does have is diminished significantly as the
bleach sits in warehouses and on grocery store shelves or inside your home or business
[50% loss in killing power in just the first 90 days inside a never opened jug or
container] Chlorine ions constantly escapes through the plastic walls of its containers.
ion structure also prevents chlorine from penetrating into porous
materials such as dry wall and wood--- It just stays on the outside
surface, whereas mold has protected enzyme roots growing inside the
porous construction materials. When you spray porous surface molds
with bleach, the water in the water solution soaks into the wood while
the bleach chemical sits atop the surface, gasses off, and thus only
partially kills the surface layer of mold while the water penetration
of the building materials fosters further mold growth.
Chlorine Bleach is NOT registered with the EPA as a disinfectant to
kill mold. You can verify that important fact yourself
when you are unable to find an EPA registration number for killing mold on the label of
any brand of chlorine bleach.
New University Study Discovers That Bleach
is Ineffective In
Killing Mold on Wood
"While bleach is often recommended for
remediation of surface mold on wood, our [university research study]
results illustrate that the treatment does not eliminate the surface
microflora," is the conclusion of the Oregon State University
study of the effects of chlorine bleach on mold growth on Douglas fir
wood [an important timber crop in the state of Oregon]. The research
study was conducted by Professor Jeffrey Morrell, Dept. of Wood
Science, Oregon State University, as assisted by Adam Taylor [graduate
research assistant] and Camille Freitag [Senior Research Associate],
as published in Forest Products Journal, 54:4, 2004.
To prevent mold effectively, you can use a low-cost Mold Home Remedy
Recipes and other Mold Killing and protective products available at
Bleach as a mold disinfectant is
best used in the kitchen and bathroom for countertops, tubs and shower
glass, and other hard surfaces.
Often people choose to use home-made alternatives to commercial
cleaning products because they believe that naturally occurring or
naturally derived substances are less toxic and better for the
environment than commercial products. However, scientists have not
found a correlation between naturalness, toxicity, or environmental
compatibility. In fact, some of the most toxic substances in existence
are naturally occurring substances. Furthermore, commercial products
are tested in terms of effectiveness, safety, and environmental
compatibility. Nonetheless, if you choose to use a homemade cleaning
solution, you MUST use precautions.
In addition to the factors listed in the following table, there are
safety factors that should be considered before making or using a
homemade cleaning product. For instance, you should NEVER mix
cleaning solutions. This is especially important because products that
are safe when used separately can become hazardous if mixed with
another product. An example of this type of product is chlorine
bleach. NEVER mix chlorine bleach or a product containing
chlorine bleach with ammonia or any product containing ammonia or with
any acidic products such as toilet bowl cleaners. If these products
are mixed, toxic gases can be released. Furthermore, mixing household
chemicals can also result in heat or explosion or household chemicals
can become less effective if mixed with another chemical. Still yet,
some household solutions simply do not work well or at all. This is of
particular concern when individuals are trying to disinfect a surface,
or kill disease causing microorganisms.
The following table outlines some of the advantages and
disadvantages of commercial products and homemade alternatives.
|Meet Federal Safety Regulations
||Not Subject to Federal Regulations
|Proper Precautionary Labeling
||No Precautionary Labeling
|Ingredients Known to Poison Control Centers
||Ingredients May Not be Known to Poison Control Centers
|Child-Resistant Closures Where Needed
||Usually No Child-Resistant Closures
|Packaging Compatible with Formulation
||Packaging May Not Be Compatible
||Product May Degrade in Package
|Won't Grow Harmful Bacteria
||May Grow Harmful Bacteria
|Won't Harm Goods When Used as Directed
||May Harm Valuable Possessions
|Careful Quality Control
||Varies By Consumer Skill
|Evaluated for Safety and Environmental Compatibility
||Not Evaluated for Safety or Environmental Compatibility
Source: The Consumer Products Handbook: A Comprehensive Guide to
Today's Household Chemical Products. (1992) Chemical Specialties
Manufacturers Association, Inc
Disadvantages of Using Chlorine Bleach
The following disadvantages of using chlorine
bleach were published "Bleach Usage" on Facility-maintenance.com---
1. Chlorine bleach lacks the ability to
cut through dirt. A surface or object being cleaned and
disinfected must first be cleaned if bleach is going to be used as
disinfectant, adding time and labor costs to any project. “Organic
material readily inactivates these disinfectants, so the surface must
be cleaned first,” said one industry consultant. “You have to
essentially double the time that it should take to clean and disinfect
a soiled surface.” [In a
2004 study of five different household products to try to clean a
moldy shower curtain, The Wall Street Journal recently reported
that the least effective product was chlorine bleach.]
More disadvantages of chlorine bleach are as
· Bleach loses strength rapidly: Carol Bush, area manager
for contract cleaner Central Property Services, Pittsburgh, said a
bleach/water solution left on a shelf for any period of time will lose
its effectiveness. At the same time, said cleaning industry educator
William Griffin, Cleaning Consultant Services Inc, Seattle, bleach
loses its effectiveness quickly when being used, “gassing off” before
most disinfecting can be accomplished.
· Bleach can hide dirt: The bleach can make some soil
transparent, leading a cleaner to think he/she has actually cleaned a
surface when in fact the soil remains there, said Michael Smith,
academic custodial supervisor, Western Washington University,
· Bleach damages floor finishes: Bleach attacks floor
coatings, eating away at their effectiveness.
· Bleach damages fibers, carpets etc.
· Bleach corrodes hard surfaces: Metals and other surfaces
can not only be corroded, but discolored.
· Bleach causes health concerns: Improper use of bleach –
either using too much or mixing it with certain products – such as
those that contain ammonia hydrochloric acid, acetic acid and
phosphoric acid – can create hazardous health conditions.
health hazard: bleach can contaminate groundwater.]
What should you use to kill mold
Learn the 25 steps recommended for safe and effective