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Could acid be destroying my family's lives and home?


An ongoing discussion beginning back in 2006 ...


Hello, I am a homeowner. We hired a contractor to put a gray cement stain and poly coat on our garage floor. He first had to treat the cement with some type of acid to make it rough. My husband believes that he used Muriatic Acid [affil. link to info/product on Amazon] . At some point he also used a cleaning solution with a power sprayer to clean the floor. He did one coat of paint. I think when he returned to do the second coat, he washed it off again to make sure that it was clean. He may have done this three times. We had some problems with it peeling up where the vehicles were so he came back to work on things a couple more times. In hindsight, we should have hired someone who specialized in this type of job.

The painting of the garage floor included a cutout storage area that is really the underside of our stairway inside the house. It is an open stairway that is open to our two story high formal living room that we do not use often. The laundry room is also on the other side of our garage wall.

We live in Texas. Like most people here, we have a cement slab foundation level with the cement in the garage (no basement). Rarely do people open their windows here. It is usually too hot to be comfortable and you don't want to let in humidity. It is a short time span in spring or fall that is appropriate.

The contractor was there several times between November 2004 and March 2005. My husband began noticing a strange smell on and off in his office (near the staircase)and in our laundry room. He asked me if I was using any new cleaning products or furniture polish.

In April, 2005 on a windy day I noticed a strange smell. It was a rare perfect temp day so I decided to air out the house....threw open a bunch of windows including some in the formal living room directly opposite that staircase/garage wall. I left and when I returned.....the smell was so strong. If you walked up the stairs it seemed to be hanging in the air in the middle of that 2 story high room. But, it wasn't just there. We have a separate staircase at the rear of the house that goes to a separate guest room/bath. It seemed equally as bad or worse there. It was confusing where it may be coming from. My oldest son and I could not be in the house for ten minutes without headache, my ear would swell shut and congested. My oldest son and I ended up on antibiotics later. It didn't bother my husband as badly but after repeated exposure it began to give him headaches. We tried to keep our youngest two children away. It was extremely strong for 2 days and slightly strong for an additional 2 days. It was strongest on the lower levels and half way up the stairs. Less upstairs. We went up into the attic and it was not noticeable there.

OK, we do not know for certain what this was from. First let me share people's descriptions of it. We had many neighbors and relatives come over to help us figure it out. People described it as medicinal, chemical, cleaning product, ammonia, and one kid said it smelled like his amoxycillin medicine. Others asked if it was natural gas or sewer gas.

We had sewer people come....didn't think it smelled like sewer gas. Put citrus in the city portion of our line outside house but we couldn't smell it. We made sure every drain in the house had water in it. Months later we did have plumbers perform a smoke test and there was a toilet that had a seal leaking but not sure that was really the problem. I had more plumbers come again....they raised a sewer vent pipe to make sure it wasn't coming back into the attic vents and they put a scope into my outlets but couldn't see any cracks or problems. Plumbers are not cheap.

We had the fire department come one of the first days while it was still really bad. They said no it wasn't natural gas. Their oxygen meter said the oxygen levels were good. They said we shouldn't stay here because whatever it was burned their eyes.

We had terminix come....they said it didn't smell like any dead animal they had ever seen.

I had a mold guy come. He performed air tests. Some but not unusually high levels of mold but the one odd thing was RUST/SMUT which can indicate that you have bacteria growing in your HVAC system. So, we had our coils disinfected and our ducts cleaned and UV lights put into each of our HVAC units (we have 3 because in Texas you have zones for controlling A/C) Between that and his air test....cost almost $3,000 total.

We moved out for those first four days or so. Then it seemed to go away after the HVAC cleanings so we went back. We concluded that it must really have been the HVAC coils.

In September, I had someone steam clean the carpet on those steps. Not sure that is related but several days later the smell rose up again but not quite as bad this time. Before I thought about this muriatic acid...the possible connection to the steam cleaning to the stairs didn't occur to me. So, I had another mold person look all over my house for signs of a problem. I talked to my home builder, he sent plumbers. I had people who painted our house put new vents on the eaves because they looked clogged with paint. My husband resealed all of the other toilets in our house in case there was a sewer gas leak that we missed.

Later, still searching...we ripped out our master bathroom shower because we were concerned that maybe moisture back there was causing a smell and that the air currents from opening doors etc was pulling it out to those other areas. We do not think that was the problem

To this day, when we open windows in our house....a tiny bit of that familiar smell comes out. A stranger may not notice. But, my family....my sister...people familiar with it can recognize it.

The past couple of months, that spare guest room at the back of the house now has a musty smell but it might be in the HVAC system. It is hard to tell for sure.

Health ISSUES at our house during this entire saga:
After the garage work, but before the big smell in April: One night in January 2005 my middle son (12 years) awoke during the night with a huge lump on the side of his neck. He is allergies to various things so it was concerning but it went away after I gave him Benedryl. But, that same night while I was helping him....I fainted (which I have never done before). In April after the big smell for 4 days...my oldest son (15) and I had to be on antibiotics to recover from the congestion in our heads that started when this big smell entered our house. In September 2005 I became very ill for 3 weeks (could not even fathom taking a bite of food, loose stools, thirsty, tested for hyperthyroid and the doctor said I had mono which is inflammation in your body). My lymph nodes and abdominals were swollen, my legs had fluid swelling my ankles. My feet and hands were numb/tingling off and on. I would awake from a dead sleep and suddenly zoom to a panic like something just zoomed into my brain. My vision seemed blurrier than usual.

I decided that it must be something (whatever this smell was on and off) that was causing me to be sick since I was the only one that was at home day and night and slept on the bottom floor level. My kids slept upstairs and went to school during the day. My husband was at work during the day and traveled alot at that time. I decided to leave with my youngest two kids for a week while my husband opened all of the windows and tried to get the smell to come out strong again so that someone could come help us figure it out. It seems to be bigger when it is windy outside or when the wind is from a certain direction. It has not come out strong again.

I had someone inspect our slab foundation. He could not find a crack or any reason to believe that our foundation is cracked.

My daughter (9) seems to have tummy aches several times per week but it is hard to say that it is from our house. My 16 year old son has bad acne but it is hard to say that is not normal for him....his room upstairs shares that garage side wall with the staircase.

I recently came up with the theory that maybe it had something to do with that acid and the cleaning solution and power sprayer used by the garage contractor. Maybe some of it went under the wall and/or under the carpet and we just didn't notice it was wet. I think it makes sense that if the windows in the house are open and maybe the garage door is up....a draft would come into the house underneath that wall. The carpet is cream color and is 7 years old...but the strip along the staircase wall is darker than everywhere else and if I peel up a corner of it, it dark all the way to the edge instead of being clean where it was tucked down under...the tack strip looks darker there than in other places and the nails in the tack strip are a bit rusty. But, I can't see anything else wrong. When I show that dark strip along the wall to people though....they say it is normal as carpet ages and it is probably just filtering out the dust there because of how the air comes down from the air vents.

Please help me.....MY QUESTION: Is it reasonable to think that the acid or chemicals used to treat the cement floor in my garage would get underneath the wall or carpet? Could it cause the reactions that I described? Why wouldn't we have smelled it immediately after they did the work in the garage? Would the odor change with temps and humidity? It couldn't have been in big enough doses to get the carpet soaking wet or else we would have noticed that. If so, would it eventually dissipate so that we can't smell it anymore....and so that it is not harmful any longer? Would it just make the carpet look darker? I can't see that anything is wrong with the carpet padding below. I would like to bust open the walls but my husband thinks that may just be a waste of money. We really thought it was the HVAC when we spent money on that. We really thought it was plumbing when we spent money on that. We are not made of money. I want to know if this is a reasonable idea before I tear my house apart. Is there a blood test or something that would show that we have been inhaling muriatic acid fumes?

Thank you for your help. I have asked everyone that I can think of. I am running out of theories to investigate.

[last name deleted for privacy by Editor]
homemaker/mom - McKinney, Texas


The muriatic acid was probably gone the day it was used -- it is quickly neutralized to salt water by contact with concrete or metals. Serious exposure to fumes would have been immediately obvious. Blood tests cannot reveal muriatic (hydrochloric) acid exposure, as blood is naturally salty.

Check for containers of cleanser, bleach, ammonia, swimming pool chemicals, windshield washer fluid, etc. Dry cleansers with bleach powder react with humidity to give a chlorine smell.
Did the paint harden properly? Sometimes, two-part epoxy smells if not properly mixed (doesn't fully cure).
Moldy carpets are beyond the scope of this venue. Consider tile floors.
Good luck.

Ken Vlach [dec]
- Goleta, California

contributor of the year Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.



Just as a guess, I think that two-part epoxy thing may be the issue. Which raises the question of what happens if you now wash an epoxied floor with hardener?

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


The Acid would not be a problem. It is known as HCl, when mixed with the concrete NaOH it forms simple NaCl or table salt. Many Epoxies will never cure if not mixed properly and leave the smell around forever. Mold related issues are outside the scope, but every smell you mentioned could could be mold related, and would come and go with each bloom. It will never come out of carpeting.

Ron McKenzie CEF
Quality Chemistry Consultants - Huntington Beach, California, USA



OK, acid may evaporate the same day off cement and metal...but, what if it went underneath my wall and was absorbed into the wood?

The paint on the garage floor has not stayed well. It has peeled up where we park the cars and even where the kids bicycle kickstands hit it. Would that indicate that it was mixed incorrectly? I am a very unhappy customer.

How do I determine whether it is a two part epoxy?

[last name deleted for privacy by Editor]
- McKinney, Texas


The peeling paint (non-sticky) suggests that it cured OK , so no two-part epoxy mixing problem. More likely it was lifted off by moisture coming through the concrete or else, oil stains weren't adequately cleaned from the concrete.

Both peeling paint and mold could be from excessive moisture coming through the concrete slab.
Do this test, per ASTM D4263: Duct tape an 18 by 18 inch square of clear polyethylene sheeting to the bare concrete, sealing the 4 sides. Wait at least 16 hours. Check for visible moisture on the underside of the plastic and on the concrete surface.

Moisture may indicate the absence of a vapor barrier (e.g., plastic sheeting) beneath the concrete slab. Check whether a vapor barrier is required by law (your local building code) if the builder is still around.
Possibly, a waterproofing seal could be used on the concrete.

P.S. The wood (& concrete, plaster, steel, soil, etc.) would have neutralized any residual HCl a long, long time ago.

Ken Vlach [dec]
- Goleta, California

contributor of the year Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.


First of two simultaneous responses -- 2006

In reference to the garage I had a similar paint peeling problem with my garage floor. I determined from a tape test (put 2 pieces duct tape on floor forming an X and pull tape off quickly) which revealed the floor under the paint was sealed, thus paint was peeling. Went to home depot and rented a surface grinder and took about 2 hours to grind off the paint and seal in my two car garage. Then I mixed the product per instructions and coated the floor. No acid was needed and the floor looks great. This may be the problem with your floor peeling

In regards to the smell, I feel terrible for your family. Let me offer one possible source, look behind the walls. We had an office near Waco, Texas which was poorly built years ago. On occasion we would get an awful smell in the office that came and went just as you have described. After looking everywhere we pulled a wall panel back and found a dead rat. Well, this happened a few times after with field mice and rats before we finally moved out. I must say that this went on for months just as you had described.

Perhaps someone with a small flexible camera system (like plumbers use to find cracks in pipes) can punch a small hole between your wall studs and look for rodents or heck anything that may be the problem. That way you would know what, if anything, is in the wall and it would be easy to patch and touch-up the walls without ripping them out.

Best of luck.

Rick Hall
- Hickory, North Carolina

Second of two simultaneous responses -- 2006

Muriatic Acid, as was mentioned earlier, is the old, historical name for hydrochloric acid. Hydrochloric acid is the acid produced by your body, often called stomach acid, to help in digestion. The chances of someone being allergic to hydrochloric acid are very near zero. Hydrochloric acid is also a very common industrial chemical. The symptoms of Hydrochloric acid vapor exposure are very well known, and have been known for many decades. They include coughing, choking and inflammation, but not the symptoms you mention in the way that you describe them. Hydrochloric acid fumes would have produced an immediate burning sensation in your mouth and nose - it's very irritating. Again, as has been mentioned in other responses, hydrochloric acid is very reactive, and would have entirely turned to salt water by reacting with the chemicals in the concrete, wood, carpeting, and/or dry wall in your house within hours of being applied.

You describe a recurring smell, one that can be cleaned out of the house, but that comes back under certain conditions. This smell was not apparent until several months after the work had been done on your floor. This behavior is not typical of a chemical spill, but is extremely typical of mold growth. While it's possible that the acid could have decomposed some of the chemicals used to make your carpet, the chemical release would have been a one-time event, occurring the same day or a few days after the acid was used. A chemical spill would not be able to "replenish" itself.

The chances of there being mold in your carpets and walls is much, much higher than there being a chemical exposure causing your problems. Again, as has been mentioned before, once mold has gotten into your carpets, there is no way to eradicate it completely. The only thing that will get rid of the mold is to replace the carpets, tack strips and padding, after washing your floors with bleach. If the mold is in the walls, you'll probably need to replace the drywall also. (You can check the walls by cutting out a small square of drywall and looking at the inside of the wall - no need for major demolition). Please note that if there is moisture coming up through your foundation, that has to be fixed before you even consider replacing anything, or you'll have exactly the same problem with your new walls and carpet in a year or two.

Just to be thorough, the other issue you might look into is called Multiple Chemical Sensitivity. This is a DSM IV diagnosis, however, so you'd need to find a competent specialist.

To summarize:
1) Muriatic acid is not a strange, little known chemical. It has been used in industrial processing for more than a hundred years, and the effects of exposure to it are very well known.
2)Chemicals react, and then are depleted - they do not hang around in your house for months continuing to make you sick.
3)The problems you mention are typical of mold exposure.

Robert Zonis
Product Development Chemist - Shelbyville, Tennessee, USA

Ozone Generator

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April 20, 2012

I have the same issue. I detect an odor that suggests gas leak. I first became aware of the odor when I removed a telephone jack cover on a wall to change the wiring. A tech from the gas company could not detect a gas leak. He said the smell was lumber. Well, there is a hint of lumber in that odor, but the lumber in a house isn't supposed to give off an odor that suggests a gas leak. I suspect the odor is from mold growing on lumber. In the past, I'd had roof leaks, but the roof has supposedly been fixed. The smell gets worse if (1) I open windows, as this creates a negative pressure in the rooms that sucks the air out of the walls and attic into the rooms or (2) if it's windy, as this pushes air from inside the walls and attic into the rooms.

Since the concentration of this bad air can vary with the air flow, it's quite possible that air samples taken at a time when the air flow is low will not disclose a mold problem. Don't believe the negative mold tests. Your nose is a much better mold detector. Another problem with mold tests is that only detect the types of molds that tests were designed to detect.

The odor and health problems you describe strongly suggest a mold problem. Investigate whether you have mold in the attic and roof. Mold spores in the attic could be entering the walls and getting sucked into your rooms when it's windy or when you create negative room pressure by opening windows.

Bob Anderson
- dana point, California

May 18, 2016

Hello. Did you ever find the cause? I also have a similar issue but found no resolution. This is the second May that it started. First starts in garage and then moves to the rest of the house. Ac has not been on all year. House is on a slab, with upstairs above garage with a loft. It started last year. We have epoxy garage floors that are chipping too, but they have been installed for 10 years since the house was first built. We had all the same people come out, fire department, health department, plumbers with camera, gas and water company, all which could smell and taste a metallic type taste. I also have low blood pressure, during this time when I always run average. Low, like 15-20 low. 108-115. I have woken up in a panic like you and grasped for air within the first week of smelling it again. It's extremely odd. I also have more liquid in my ears and I almost threw up several times the first two weeks. I have even tore up drywall and no luck. Last year was the first year and there was no change, other than a week before we had a company out to spray for weeds and they burnt up the lawn in a few areas. We thought it was related to that, but obviously since it came back this year it, so likely not. The smell is almost like a metallic dirty trash and thought that was what it was in the garage. It makes you mouth very dry. Even my dog has dry mouth. More so in the beginning. What could it be in May that could cause it to start? It does seem when it's hotter outside it's more noticeable. Like 70-80 degrees I notice it. Always strong in the garage. I live in a brick home with small siding on the top sides. One thing I did notice is that I had chairs hanging in the garage on a rack, I came home in May and the chairs were on the ground and the brackets ripped from tbe walls. It had been up for about 8 months, but I did it myself and didn't hit the studs, but did use 100 lb screw anchors. The same time, my front door wreath was on the ground. Not sure if its coincidental or not. Thanks for your help.

Chrissy House
- Indianapolis, Indiana USA

December 5, 2017

! I read this thread and thought "Chinese drywall." After Hurricane Katrina 2005, many people here in NOLA had to repair or rebuild their homes. Many used a then-new drywall from China. Turned out, the drywall had a high sulfur content that corroded metals and caused health problems. I noticed the original post is from 2006 and the second post describing the same problem states the house was built in 2006. Perhaps this is merely coincidence. But it's worth consideration: Is an unsafe building material the source of the problem?

D Morgan
Homeowner - New Orleans, Louisiana, USA

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