Home Cleaning Tips Cross Contamination From a Moldy Home

Cross Contamination From a Moldy Home

by Catherine

Do We Really Have to Leave and Get Rid of EVERYTHING?

Mold cross contamination when you have to leave or remediate your home is a huge concern—and, if it is not, it should be. The stressful topic can begin with a large cross-contamination question, like if we have mold, does that also mean that all of our possessions have mold too? And, can scale down to more focused questions: Is my car also contaminated since I drove it while living in the moldy home? Is a mattress contaminated if it wasn’t in the same room in my house as the mold? Can some things be cleaned and taken with us immediately? Can one contaminated object infect my whole home? As you can see, the line of questioning, scrutiny, and intricacies of cross contamination can be totally endless and totally overwhelming. It doesn’t have to be, though. The matter of cross contamination can actually be broken down quite scientifically and methodically to help you with the whole ordeal.

To begin, I think it can benefit anyone dealing with mold to look at the cross-contamination issue from a macro-perspective and to understand how mold, mold spores, fragments and mycotoxins (gases emitted by some mold species) actually spread and contaminate an indoor space in the first place. With that knowledge, you can better approach dealing with your possessions and deciding which things to try to save or to take with you. There will always be unique situations or specifics that don’t fit this guide, but for the most part, it should help just about anyone dealing with a mold problem.

When the Mold Issue Is Small

Before I get into the nitty-gritty, I want to acknowledge that not every situation requires drastic action. There are many instances when a mold issue is confined and small. In these cases, simply containing, fixing and remediating the mold problem, and then washing, wiping down, or getting rid of items close to the source is enough. Also, if your immune system is robust and the mold hasn’t affected your health, you may be able to tolerate cleaned possessions better than others would. But, if you are ill, your family members are ill, and you have had to flee a moldy home, you should take the utmost caution in regards to your possessions and cross contamination.

What is Cross Contamination and Why Is It Such a Problem With Mold?

Cross-contamination is the process by which bacteria or other microorganisms are unintentionally transferred from one substance or object to another, with harmful effect. It is an issue in a “sick” indoor space, because mold spores, mycotoxins and the other pathogenic microbes in a water-damaged environment spread by way of central HVAC systems, disturbance, and contact to all surfaces and materials. Porous materials are especially vulnerable to mold. This is because the toxins produced by molds are basically free radicals. They have the ability to bind to fabrics and to release spores and additional mycotoxins over time. The finer spores and particles released by molds can permeate porous surfaces and are not easy to remove.

(Note: To put things in perspective, most mold spores range from 1 to 100 microns in size, with many types as small as 2 to 20 microns. You could actually place over 20 million 5-micron-size mold spores on a postage stamp. Further, a study published in 2009 by the Science of the Total Environment stated that buildings that had long-term mold damage showed increased amounts of sub-micrometer-sized fungal fragments. The health impact of those fragments was greater, because they could be inhaled much more deeply by occupants.)

If these particles and mycotoxins remain on surfaces and in fabrics, they can very easily contaminate a clean environment as soon as they are disturbed. Pathogenic bacteria that are commonly found in indoor environments that harbor dangerous mold species can also be aerosolized, giving them the same ability as the mold to contaminate furnishings and clothing. A double whammy for your immune system, and another reason why mold illness tends to ignite sleeping viruses and bacteria that may have never been a problem before.

As a matter of fact, you probably already recognize the dangers of potential cross-contamination and are already putting some protective practices into play in your home. For example, think about your kitchen: I’ll bet you are extremely careful not to use a knife that you used to cut raw chicken to also cut your vegetables without cleaning it very thoroughly first with soap and hot water. This is because you are doing all you can to avoid the possibility of cross contamination from Salmonella. The same precautions should be taken with mold and mycotoxins, and items that have been exposed to them should not be moved to or used in a mold-free environment unless they are properly cleaned.

Suffice it to say that there is much more going on than what you can actually see when mold has become a problem in your environment. Asking questions and being concerned about your possessions and the décor inside of your house is prudent and wise. I once read a quote from a mold specialist whom I consider a mentor that warned occupants of severely mold-damaged homes to “treat the home and the possessions in it as if the home was on fire.” In other words, as you would in a fire, leave with the clothes on your back, and quickly replace those. Priority one is to get out. That is what is MOST important at the immediate time. You can later figure out if and how you can salvage the home and the possessions. Although extreme, I like that line of thinking, because it doesn’t close the book on reclaiming your home and your things. It just supports removing yourself from the danger, so that you are able to deal with the details when you are safe.

When You Are Ill, Have or Have Had Mold Toxicity, Or Have a Severe Mold Infestation

The first and best choice is always to vacate the home, to bring nothing with you, and to make decisions about your belongings later. Once you are settled in your temporary environment, you can start planning your belongings removal and/or remediation strategy. I will also say that, from my experience, going through your possessions is SO much easier when you are out of the moldy environment. When you are in the mold, your thinking is cloudy and you feel terrible all of the time, so the desire to hold onto things is, for some reason, much greater. Out of the mold, with a clearer head, your desire to keep things will be less than your desire to continue healing and to let go of things that could interfere with recovery. I am not saying that it is easy. What I am saying is that you have already taken the enormous step of leaving, so getting rid of things that could bring you back to square one by contaminating your new space is far less daunting.

Finding Peace With the Process

You want and need to do this right the first time. (I actually have a previous post on this topic that you may want to also read.) Once you have successfully remediated your home and it has passed inspections and testing, or once you have moved to a permanent, safe environment, you can always bring more things in—once they are successfully cleaned, of course. But, it is much harder to remove a problematic item once it is in your new environment, so always keep that in mind throughout this process.

It was also my experience that totally getting away from our moldy belongings gave our bodies the separation that they needed, so that we knew immediately which things caused us problems with our health and which things were safe when we began reintroducing them. I liken this heightened sensibility to mold to times when you have given up things like caffeine. Maybe you drink and cup of coffee each morning as part of your routine, so over time, you have become less aware of its effects. If you give up caffeine for a month or so, when you finally have it again, you are acutely aware of how you feel when you drink it. Sometimes, the jolt is profound.

Getting Started: Making Order Out of Chaos

(Note: Cleaning mold- and mycotoxin-contaminated items is a whole, huge topic in and of itself. I am not going to address that specifically in this post, because it is just too vast to even begin to cover. There are already many posts about cleaning strategies for specific items on the blog, like shoes, purses, dry-clean-only items, clothing, upholstered items, your washing machine, stuffed animals, dishes. If you are looking for something in particular, just use the search tool at the top of the page.)

It is my suggestion and experience that removing, discarding, and/or cleaning belongings should occur prior to any mold remediation or demolition. Some people decide to leave items in the home, if the space to be remediated is small and contained. If that is the case, sometimes you can leave your belongings in other areas of the home without worry of contamination. In addition, there are ways of keeping your things safe with proper protections and equipment put into place. If you intend to do this, you should get professional help and advice with setting all of this up properly to make certain you are not allowing disturbed particulates to enter otherwise clean areas of your home. But, for severe cases where there is illness involved and for large-scale mold remediations, all belongings and contents that you would like to clean or save, must be removed PRIOR to any work on the home.

For the purposes of being methodical, you should start by listing the things that you will discard. These may include things you have been storing, but no longer need, porous items that were definitely exposed to the mold (like mattresses and pillows, for example), items that have visible mold growth, food and spices, any papers, magazines or books that are not of sentimental value, etc. There may be others, but you get the idea. This is usually a great way to begin, because these items are generally ones that are not as treasured and are easy to check off of your list. You can have these items bagged and thrown out or put by the curb for pick-up and disposal.

Once the discard list is complete, decide on where you are going to store the items that you are going to try to keep. This often means renting a storage facility for a period of time, storing the items in the garage, or moving the items to a friend or family member’s garage. This may also have to be a combination effort, where some things go in storage and some things stay in the garage. You just have to be realistic about the space available and the number of items you are trying to keep. To be honest, our lack of available space and funds ended up be quite liberating for me, because it forced me to go ahead and discard some items that I was trying to hold onto, even though I knew they were not going to be able to be saved.

Whatever you decide, you will also need to decide on how you will transport these items. We were able to store some things in our garage, and then had to put some things in storage. At this point, we had already decontaminated our cars, so we didn’t want to risk re-contaminating them. Thus, we rented a U-Haul trailer to load all of our bins into for storage transport. If you can afford to hire movers, this is obviously preferable, because it frees you up for other tasks.

For containing the items you want keep, you need to buy lots of plastic and/or rubber sealable bins of all shapes and sizes. Do not use cardboard boxes, because cardboard is almost impossible to decontaminate and mold grows like wildfire on it. It can also not be sealed. You need to be able to seal the contaminated items in the bins for storage, or for after cleaning, so that they are not re-contaminated or able to cross contaminate your new space or car. The bins are also very easy to clean, so they can be wiped down thoroughly and used again and again during this process. Boxes cannot be cleaned and reused, so although purchasing bins may seem expensive in the beginning, you will get much more use out of them than you ever would out of the boxes. There are many cheap options at Walmart, on Amazon, or at local home improvement stores.

To use the bins, you will be taking them one-by-one into the home (wearing proper protective gear—gloves, N95 Mask, Tyvek suit, and eye protection—as outlined by OSHA’s and the EPA’s websites for mold), or having someone do this for you, and going room by room, placing the items that you wish to keep inside of the bins.   Before exiting the home, you will close and seal each bin. Once outside of the home, you will wipe the outside of each bin off with hydrogen peroxide or EC3 Mold Solution Spray. This will prevent the bins from cross contaminating anything once removed from the home.

Making Decisions About Your Belongings

From a cross-contamination perspective, you need to be looking at your belongings like a remediation professional—easier said than done, I know. In other words, you need to be thinking about which items can be effectively cleaned for mold. Those are the items that you can try to keep. (Note: I also advocate testing things post-cleaning with EC3 Mold Screening Test Plates to make certain that the spore counts are safe BEFORE you bring those items inside.) This may sound like a tedious thought process, but as I said before, it is MUCH easier to bring more items in later, than it is to remove an item once it has contaminated your space. Thus, think about it this way: The key to successfully cleaning an item is to be able to eliminate the dust and particulates that carry the history of the “sick” home from it. For non-porous items this is usually a surface-cleaning issue. For porous items, it is much more complicated. Sometimes an successful cleaning can be achieved by washing the item with an additive that is proven effective against mold and mycotoxins, like EC3 Laundry Additive, sometimes by rinsing or wiping the item down, sometimes by using a HEPA vacuum (a vacuum with a High Efficiency Particulate Air or High Efficiency Particulate Arrestance Filter) and wiping or cleaning—whatever the case, think about whether or not any of these techniques could be feasibly used on the item you would like to keep. If not, it is best to discard it.

To make this process a little easier on you, here is a general list of mostly salvageable and a list problematic items to help you along in your decision-making process:

(Note: I have also included links to previous articles about cleaning these items, or brief suggestions on how to clean them. These are not all-inclusive lists, but just a way to get you started and to keep you organized.)

Salvageable Items

(These items can usually be successfully cleaned.)

Problematic Items

(These items are difficult to effectively clean. There are techniques that can be tried, but are not always successful. Keep these items with caution and with the knowledge that you may have to discard them later.)

  • Computers or Electronics with inner fans
  • Appliances (the coils and fans can harbor dust)
  • Mattresses, Pillows
  • Dry-Clean Only Clothing and Coats
  • Leather Purses and Shoes
  • Books, Papers, and Photos
  • Air Purifiers (even when filters are changed, they tend harbor contaminants)
  • Upholstered or “Filled” Furniture (anything that “inhales” and “exhales” when some sits on it is very difficult to clean)
  • Laminate or Wood Composite Furniture (these materials hold onto the mycotoxins and are difficult to clean)
  • Rugs

Getting on With Your Life

Once your belongings are sorted, removed from the home, and cleaned. You can begin reintroducing them to your body and your environment. I always liked going to the storage unit first, and seeing how I reacted to things there before trying to bring them into our home. It is a good strategy and one I recommend. Maybe it felt safer for me that way, but it definitely felt easier and less stressful. If for any reason, I felt itchy, anxious, or negative about something, I would either seal it back into a bin, try an additional cleaning method on it, or discard it. It got easier with time and as I went along. There were many things that, as I revisited them, I couldn’t remember why I had wanted to keep them in the first place. Belongings are curious that way, because when you are with them, you can’t imagine letting them go. But, after you live without them for a time, you can’t imagine why you needed them in the first place.

It took us about a year to get through everything in our storage unit. We actually moved the few bins that are still left (they contain pictures and books) to a very small unit recently. I don’t think I will ever get rid of those things, because they mean a lot to me, moldy or not. I even go visit them sometimes and take those bins outside and look through the books or pictures in the open air. It is not a negative experience, because I feel zero pressure to part with them. I don’t even feel sad that I cannot bring them into our home. I just enjoy the fact that I am healthy and able still have them with a new appreciation for what they mean to me and for how far I have come.

Did you find this post helpful? Are there specific cross-contamination questions that you would like for me to answer? Comment below or write to me at catherine@moldfreeliving.com.








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Kate - 4:40 am

I recently moved out of my apartment with mold after suffering for two years with neurological symptoms and inflammation. I left in a hurry, put things I didn’t need but thought I could save in storage, and brought with me plastic bins of clothes, books, and toiletries. I tried to be very careful in cleaning it all (laundry additive, sunshine, wiped everything down) but I’ve started reacting to the room where my things are kept and I fear I’ve contaminated my new space. How do I go about remediating now?

Catherine - 11:32 pm

I would remove all of those things and the bins from the space first. Then HEPA vacuum and fog with EC3 or wipe all surfaces, etc. with the EC3. I would also use air purification and filtration in that room until you feel your body not reacting. This could take multiple cleanings and a bit of time. Once you feel settled and like you are back to some sort of homeostasis healthwise, then reintroduce things slowly one at a time after cleaning. I would not bring the bins in, if possible. I had to do this with many things, but found that doing it more slowly was super helpful. Then, when one thing would still cause issues after cleaning it, I KNEW what it was and could just part with it more easily. It was slow, but so much less overwhelming than trying to bring lots in and wondering what exactly was causing my issues. Some fabrics are weird too and just do not come clean while others do and are fine. There is no rhyme or reason for a lot of it. Be patient and trust yourself. Take care.

Annette - 6:02 am

We have spices that have not been opened. Do these need to be thrown out?

Catherine - 7:19 pm

Hi, Annette,

If you have mold illness or had high mycotoxins as a result of the exposure, I would suggest throwing them out, even if unopened.

Erica - 10:14 pm

Did you take things like your sweeper or things like a carpet cleaner that you had used at the old home? I’m deciding what to do with those things since they were expensive and great quality. Plus deciding whether to just get a new air purifier or replace the filters in the current systems. Thank you so much for you post and opinions. It’s great to hear other people’s thoughts on these things.

Catherine - 11:10 pm

Hi, Erica,
We didn’t have a carpet cleaner, but I would recommend replacing things like that. Some vacuum’s like bagged HEPAs can have the rotating brush, filters, and bags changed and the inside and outside fully wiped down with peroxide or EC3 and be okay. The general rule of thumb is that if you can clean every inch and replace all porous pieces, it can be saved, otherwise, no. We have IQ Air Healthpros–all stages of filtration can be removed and replaced with new ones on those and the plastic shell can be completed opened and cleaned, so ours could be saved. Other air purification, filtration devices like our Molekule had to be replaced because it could not be sufficiently cleaned. I hope that helps to answer your questions.


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