Updated Winter 2024
Testing caulking and sealants was the hardest part of building my tiny house since I did this when I was highly sensitive.
This article will help you narrow in on the best caulking types. I cover the least toxic options which are low-VOC, low-odor, fast to offgas, and are suitable for chemically sensitive or anyone wanting to reduce VOCs.
You’re going to need them for repairs and renovations as well. I would suggest finding out which are non-toxic and which ones work for you before that urgent repair is needed.
I’m not interested in certifications like GreenGuard Gold here. I’m interested in the official VOC level and how fast it is to offgas. In this type of product, a high initial odor/VOC level could offgas faster than one that is lower VOC, and that can be better for the user.
There is no such thing as natural caulking though some materials like silicone are partially naturally derived.
Wood glues and white glues are now here.
Construction adhesives are now here.
This article contains affiliate links, upon purchase I make a small commission at no extra cost to you.
Top Non-Toxic Caulking/Sealant Brands
All caulks have a chemical odor when wet. I tested them at 24 hours, 48 hours, one week, and two weeks.
If you are chemically sensitive I would recommend having a non-sensitive person put a test amount into a jar and sniff then when it’s cured.
Which Caulks are Mildewcide Free?
Note that caulks labeled for bathrooms or as mildew-resistant contain a mildewcide. Currently GE I is mildewcide-free, GE II contains a mildewcide. Any caulk labeled aquarium safe is free of mildewcides, including DAP Aquarium caulk and others listed below. AFM Safecoat and Chemlink Durasil are also mildewcide-free.
1. Paintable Interior Caulk (White Polyether)
AFM Caulk is one of the top choices and is one of two main caulks to have on hand in every build and renovation.
I used this in my bathroom, you can use this around the shower and sink. It can be used around doors and windows and around baseboards and trim.
It’s used indoors anywhere where it interfaces with a paintable surface and is the non-toxic replacement for acrylic latex caulk.
My testing: Not the best when wet, not the best at 24 hours, but the best at one week.
Where to use AFM Caulk:
It can be used inside and outside. Around windows, cracks, tub and shower enclosures, backsplash, siding, walls and wood (like sealing molding), and general maintenance. It does not hold up as long in the bathroom as silicone with a mildewcide.
It is polyether resin (90-95%) with amino silane (1-3%) that does not contain solvents (it’s not acrylic, latex, silicone, or polyurethane). It is non-shrinking, and zero-VOC once cured.
Mildewcide: none. Elongation: 35%. Color: white. Paintable: yes
Where to buy: You can buy this online from Green Design Center.
Alternatives: ChemLink NovaLink 35 is a similar paintable elastomeric silane-modified polyether but comes in different colors (if that is needed) PSI of 145; Chemlink Durasil in white; 3M Marine Adhesive Sealant 4000 also seems very similar (polyether 15-40%, white pigments 35-70%, plasticizer 10-20%, silane 1%), PSI 220-240, and is paintable. (It retains its rubber-like odor for many months).
This video goes over the least toxic caulking options:
2. Non-Toxic Silicone Caulks
Silicone caulking is non-toxic and highly tolerable once cured. But if you are going to be around during the application (or even within two weeks of application for the super-sensitive) be sure to pick the least toxic option.
For most new builds and renos you want one paintable caulk (polyether, below) and one silicone caulk from this list. Silicone is generally for kitchens and bathrooms where you don’t need a paintable surface.
Neutral cure silicone is the least toxic type of silicone – specifically oxime or alkoxy neutral cure silicones – they offgasses alcohols or methyl ethyl ketoxime, not acetic acid. Oxime silicones have good adhesive strength and suitability on different materials.
Which of the two is better (chemically) depends on your specific sensitivities. There is also a small chance you could find an acetic acid cure better after waiting out the cure time, which I would say is 18 days.
Oxime or alkoxy-type neutral cure without added mildewcides are the least toxic types of silicone caulking.
Top Brands:
- ASI 388 – is neutral cure (oxime type) without a mildewcide from Amazon. Lowest odor when wet.
- DuraSil – is nuetral cure (oxime type) without mildewcide, from Green Design Center. It says not for use on tub and tile applications, this is because it has no mildewcide.
- GE 2 Advanced – is neutral cure (alkoxy type) for kitchens and bath, and it’s easy to get from the hardware store or Amazon. It does have a mildewcide. Very close second place to lowest odor when wet.
- Silco RTV 4500 – acetoxy cure silicone, more typical type for kitchens and bath. Very potent when wet. Though possibly preferable after 18 days of curing. No mildewcide (food safe).
Testing by the Chemically Sensitive:
Preferences between polyether caulk (like AFM Caulking, Eco-Bond, and Chemlink Clear) and silicone:
- It is possible to prefer polyether caulks (in the sections below) over silicone. You can easily have a different preference when it’s wet, compared to a few days and compared to a few weeks. Polyether can retain more of a rubber smell even after a few weeks compared to silicone.
Preferences between the two top choices of silicone:
- The choice between alkoxy and oxime would be very individual. Alkoxy (GE Advanced) smells more rubbery to me and oxime odor is difficult to describe, though it’s very subtle. Mild to moderately sensitive folks can probably choose oxime and be fine (ASI 388).
Preference between oxime and alkoxy and the more typical acetic cure silicone:
- Acetic acid/acetoxy cure silicone is VERY potent at first. It can be extremely challenging for the chemically sensitive when wet. However, if we want to get into the minute details, I found that at 18 days Silco RTV4500 food-safe acetoxy cure was totally odorless, better than the options like oxime cure (that are far less potent when wet).
Where to use 100% silicone: Windows, doors, siding, vents, around wires/pipes, in the bathroom, under countertops, around sinks, in the shower, and more.
Mildewcide: Some brands have mildewcide and others don’t. Color: Clear, white, black. Paintable: No.
Alternatives: GE 1 (not neutral cure but is mildewcide free) you can find it on Amazon and at Home Depot. Silco 7500 is neutral cure – oxime type (sometimes available on Amazon).
Where to buy:
Buy ASI 388 (the lowest odor option without mildewcide) from Amazon.
Buy Silco RTV 4500 (food-safe, strong odor at first, possibly preferable after curing) from Amazon.
What About Aquarium Caulk?
When I was building my tiny house I read that aquarium caulk (a type of silicone caulking) was the least toxic because fish are exposed to it and they can’t handle chemicals (especially biocides).
It turns out that fish are a little different than people. Aquarium caulk is usually an acetic acid cure, one of the strongest odor types when wet.
It’s priced higher only because it’s marketed differently, it’s not any different than other acetic acid cure silicone without mildewcide.
I tested two brands, Aquarium Silicone Caulker (acetic acid cure) and one called Marina. Extremely potent!
Though one super sensitive person preferred the Aquarium caulk Aqueon (even though it’s an acetic acid cure) to GE I or II and Eco-bond (clear polyether). And another did well with DAP aquarium-safe silicone (another acetic acid cure, too strong for me). It’s possible to prefer these when totally cured to the options that are less potent when wet.
Marine caulking is not the same as aquarium caulk (it’s for marine applications, not fish tanks). I tested GE Marine Silicone Sealer. It had that same pungent odor though. Acetic acid smells like vinegar times a million.
It did, however, offgas quite rapidly. After one week it was at the same point as GE 100% Silicone, and at two weeks it was just as good (virtually odorless).
3. Colored Interior Paintable Caulking (Polyether)
Chemlink makes an elastomeric caulk for sealing concrete and masonry called NovaLink35.
I haven’t tested this one, but it’s a great brand and many chemically sensitive folks do well with it.
This is a polyether that comes in various colors (white, beige, limestone, grey, and black) and can be used as a replacement for AFM Caulking Compound.
Where to buy: You can find it at Green Design Center and Amazon.
4. Clear Polyether Caulking
Clear polyether caulks can be a replacement for both clear silicone or paintable caulking like typical acrylic caulks (like ALEX brand) or white polyether.
The brand Eco-Bond (which went out of business for several years but now appears to have the website back up) was a top favorite among the chemically sensitive. It’s also a pet-safe formula.
The closest formula to Eco-Bond is Chemlink Clear, a similar clear polyether that is low odor.
Where to Buy: Green Building Supply.
Caulking Materials – What Caulks are Made of:
Polyurethane caulks – Usually contain isocyanates. This type smells strongly like typical fresh paint, and takes quite a long time to offgas. They can be made without solvents. If they do contain solvents it would typically be mineral oil, toluene, or xylene. I tried Loctite PL S40 which was really strong in my opinion. I also tested Sikaflex 1A which is probably the lowest VOC polyurethane caulk on paper but is slow to offgas (it took a full 3-4 months to really reach odorless to my nose).
Acrylic Latex caulk – They have the mildewcide octhilinone or carbendazim in them as well as a benzoate plasticizer (which has largely replaced phthalates) and naphtha (source). They are often water-based but still could contain mineral spirits, mineral oil, and propylene glycol (source). Painters caulk are usually acrylic latex and are sandable and paintable.
I tried DAP Dynoflex 230 latex caulk and DAP Alex Plus, an acrylic latex with some silicone. At one week they both had more offgassing than the silicones, though they had different chemicals offgassing. At two weeks Alex was still clearly offgassing (at three weeks I could still pick up the odor, at 5 weeks it was very mild), and Dynoflex was close to done at two weeks.
Silicone – While silicone itself is not toxic, the chemicals added to keep caulking in liquid form are. For silicone caulk, look for 100% silicone. There are different types listed below that offgas different chemicals. Once they are cured, you may find them to be essentially the same.
The chemical additives in “100% silicone” are not usually listed. Silicone doesn’t usually have a solvent but some have traces of benzene and toluene (source). Plasticizers are typically added. The biocide, if it has one, is likely to be Phenoxarsine oxide or Octhilinone according to Pharos.
Acoustical Caulk – this non-hardening sealant prevents sound leakage. They are mostly water-based acrylic. They are about 20% ethenylbenzene. In smaller amounts, they typically contain plasticizers, naphtha (as the solvent), ethylene glycol, and formaldehyde.
Sil-Terminated Polyether – specialty silicone replacement caulks are often polyether. My top pick is AFM Caulk. These are some of the most tolerable caulks but the polyether rubber does have an inherent rubber odor. They do contain phthalates.
Butyl Caulk – I tested C.R. LAURENCE White 777 Butyl Rubber Sealant. This was very potent at first (more potent than say Sikaflex 1A at first), but it offgassed faster. At 1-2 months it was really odorless to me.
Solvents common in caulking (of all types) include acetone, methyl ethyl acetone, toluene, xylene, and naphtha (Source).
Types of Silicone Caulk and What Chemicals They Offgas:
1. Typical silicone caulking is acetoxy silicone and it offgasses acetic acid. On the SDS you will see “odor: acetic acid”.
2. Neutral cure silicone, also called RTV, a less common type, is a lot more tolerable when wet. Look for oxime cure or alkoxy cure which offgas alcohols or methyl ethyl ketoxime.
3. Aquarium caulk is usually acetoxy silicone without mildewcide. It might be labeled aquarium caulk or you can just get GE 1 if you are avoiding mildewcide, which will be less expensive.
4. Paintable silicone caulk is a mix of silicone and acrylic latex.
Corinne Segura holds certificates in Building Biology, Healthier Materials and Sustainable Buildings, and more. She has 10 years of experience helping others create healthy homes.
Did you find this post helpful? If so you can buy me a coffee to support the research behind this blog. Thank you!
Gina
Should wood floor adhesives containing phthalates be avoided? Or would it be less of a concern since it’s covered by the flooring? I’m considering using a silane-based Bona adhesive for a glue down engineered wood flooring but the SDS is showing that it contains phthalates. Thanks!
Andrea
Do you know what would be a no voc mastic duct butter to use for air and heat system hvac unit were they seal the joints .
Corinne Segura
I don’t know
Lindy Hawthorne
Did you find something? How about Afm dynoflex?
PJ Rose
Hi Corinne,
I am having a kitchen sink faucet replaced tomorrow morning. I am asthmatic and extremely sensitive to caulking and environmental odors. I went to the hardware store today looking for a caulk with a list of chemicals to avoid. Left we with nothing. The sink is stainless in my apt. so probably need clear. I am only the night before finding your video so if you would kindly email back a couple brands labeled first and second choice that technician can find at Home Depot that would be a lifesaver. I have no door really to close that will help me if there’s a problem. Ace Hardware not too far but stock unreliable. Thank you for QUICK response.
Corinne Segura
the video fully explains that and the article goes into more detail
Gina
Hi Corrine! Green Building Supply is recommending Taylor Ironwood adhesive for glue down wood floors. Do you know if this is a good option or is Bostik Greenforce still the better choice? Thanks!
Corinne Segura
it’s a urethane so it might have a noticeable odor, it’s almost 0 VOC at < 0.1 g/L so should be fine for most people. They recommend what they are currently selling.
Susanna
Hello! We are having windows installed soon and not sure what they typically use in terms of sealant or what you would recommend?
Holly
Hello I am wondering if you have any recommendations for exterior caulking for a door installation? They came and installed the door and added caulking already on the bottom door sill… And it smelled so bad and came into the house that I have had to leave and have been at my parents the last two days… I came home and the smell is not as bad but it is still lingering through the house so I’ve open up all the windows for a couple of hours. But I can’t come home until the smell is gone as I am too sensitive. My question is do you recommend any sort of exterior white caulking that they can use as they are going to need to finish installing the capping on the door and I don’t wanna have to go through all of this again… Thank you so much in advance for your tip and advice
Corinne Segura
Ask them what kind of caulking they need and then see which caulking in this article corresponds to the type they need.
Kathy
I am extremely sensitive and have had no problems using GE all purpose silicone. I can apply it myself and even use it indoors when necessary. Readily available. It does have a smell, but not one that makes me dizzy/gives me symptoms and it cures quickly so you shouldn’t have to wait days. It’s not paintable but it is clear. Good luck!
AM
Our contractors are recommending Sashco Big Stretch caulk for the interior air seal of our Marvin Elevate windows. I’m tempted to use it, as performance (aka, keeping water out) is critical at this location. We are also using backer rod. Do you have any experience with this product, either performance wise or VOC wise?
Mari B
Hello, if I am reading your comments correctly, it seems that there is no less toxic or less off-gassing adhesive for plumbing? Does that include the adhesives needed for a furnace or air conditioner install or replacement?
Corinne
see the article on pipes, there is one safer adhesive though it might be impossible to track down
Katherine M
Hi! I am hoping you can suggest something my upholsterer can use when redoing my old couch. I’ve found tolerable foam but he says he needs some fast-bonding glue to stick the foam to the wood and various layers of foam to each other. Also we live in a very wet region so anything that would loosen in high humidity is a no-go. Since he’s doing the job in his shop I don’t care what awful chemicals the glue might offgas when fresh as long as it becomes inert after awhile. Any suggestions? Thanks a million!
Corinne
I don’t know the glue for that but I know there are water based options.
Axil
hoping you might help me figure out what the right adhesive for my application is.
I need to fix atone favors to what I believe to be resin for a lizard enclosure. I am not at all sensitive to chemicals and don’t have a strong sense of smell however lizards have rudimentary lungs and are incredibly sensitive. he will be in a sealed space with this adhesive for most of his life.
do you have a recommendation for a product that will do the job and a cure time that will allow me to be sure it has completely offgassed without having to trust my nose?
Axil
ugh, atone favors is meant to be stone pavers
Amazing Grace
This may be a silly question, but how toxic is the acetic acid that off-gases from silicone caulk?
If we can handle the intensity of the temporary vinegar-type smell, is it actually a toxicity problem or a smell tolerance problem?
Corinne
https://web.stanford.edu/dept/EHS/cgi-bin/lcst/lcss/lcss2.html#:~:text=Acetic%20acid%20is%20slightly%20toxic,or%20developmental%20toxicity%20in%20humans.
Amazing Grace
Yes, this document is somewhat helpful, but I could use some help to put it into layman’s terms, if you would be so willing??
Gaby Velasquez
There are large gaps around my fireplace where old tile was removed. I am told this should be filled with fire resisteant insulation- foam, caulk, etc. Sounds toxic to be heat proof. Any suggestions. The breeze coming through the gap is like having a window open.
Corinne
I don’t understand where the gap is so I don’t know if this is the right type of product. Id be cautious with that advice and make sure someone with building science expertise can advise. However fire stop caulk doesn’t look to have any flame retardants or anything out of the ordinary https://pharosproject.net/common-products/2251229
Rocky Gene Thies
what’s the best option for a PVC glue on drain pipes?
Corinne
see the article on pipes
Cindy
Thank you Corinne for posting a wonderful website that is highly informative!
Do you or anyone posting here know of good CPVC glue that is super low VC or better NON TOXIC?
We recently had a disaster with Oatey All Purpose Cement (red can) on fixing a Toliet Bathroom Shut-off Valve on the bottom area (generally used when a toliet overflows, etc).
Although it is stated that the fumes go away after ONE HOUR, that was not the case, And the fumed lasted beyond that time into days.
It also caused an inflammation in my lungs I was treated for Chemical Pneumonia, My husband, could not smell anything, but he’s hard of smelling and I got the wrath of the product,
Any and all suggestions would be appreciated.
Thank you!
Corinne
see the article on pipes
RA
Hi Corinne,
Do you know how long would it take for gorilla glue to offgas or cure? My contractor wants to use it for glueing millwork/wainscoting.
Thanks!
Corinne
I don’t know, it’s a long time since I used that.
RA
Actually I just read on their website that it takes 24 hours to fully cure, so I assume it would be perfectly safe after that…
Cheryl
Hello – I recently had my shower redone and the builder used a hybrid caulk in the corners. I think the caulk is off-gassing and was wondering whether there was something I could seal it with or to accelerate the off-gassing. It’s been 3 months and the smell is still strong.
Corinne
Heat and air the room is the best way to go. If the caulking is within the shower wet area there is no sealer that will hold up there.
Erica
Thanks for all the great info! As someone who has been chemically sensitive pretty much my entire life and has been through several remodeling projects, I wanted to encourage you to add Phenoseal to your list. It is mildly acetic smelling when wet, stops smelling within a day or two (to my nose), and works great for just about everything, as caulk or adhesive. Available in clear, black, white, gray and almond, and in different sizes. I have an indy hardware store where I can get the white, everything else I have to get on-line.
I think it was recently bought out by DAP, but so far the label (and as far as I can tell, the formulation) hasn’t changed.
Emily
Hi Corrine,
Based on the information above, would you say Bostik Greenforce is relatively safe for hardwood installation? Or is it toxic based on the fact that it’s a urethane adhesive? What is your recommendation for glue down engineered hardwood adhesive?
Thank you!
Emily
Corinne*
Sorry about the misspelling
Corinne
that’s what’s recommended
Gregory Corning
Do you know what caulks are safe to use in gardens? I am making watering wells to put around plants. I will join the ends together by overlapping and riveting. I need to water-seal the joint this creates.
I’m worried that even caulking compounds that are easier on humans might leach poisons into the soil. Do you know where I can find water-sealing caulking compounds that WON’T leach bad chemicals into soil?
The compound will also have to be able to withstand freezing in winter, and fairly warm temperatures in summer.
Thank you.
Corinne
Go with “food safe”
Ychaudhri
Hi,
Thank you for this site and information! My water purifier (jug) has a leak in it.. it’s made of clear plastic. What is the safest food safe glue to fix the leak with?
Corinne
I’m not sure, I would ask the company that makes it what type of glue is appropriate. Hopefully a food grade silicone then you can use the one on this list.
Kitty
I’m sorry but I can’t figure out how to send you a message. So I’m trying this way. Do you have any experience with eco bond adhesives. They claim no VOC’s and non toxic if I read it right.
Also I read about malting my own caulking with Portland cement but when I read about it it was really toxic. Does that mean before mixing it, while curing etc? Will it not be toxic after dried or omitting VOC’s. If so how long will it be omitting VOC’s? I sure hope you can help me. I would really appreciate it. Thank you so very much. And now I’m lost as to knowing when or if u respond all this is overwhelming.
Corinne
I mention Eco-bond on the post.
As for making your own, with Portland cement that would be grout. You can see the post on grout and thin set if that is what you are looking for.
Susan
I have to find an adhesive that is o voc or very low a water soluble to glue down cork flooring, can you help me please?
gerald aboud
What an amazing website! THANK YOU!
Ginny Plyler
I’ve really enjoyed your articles! I am chemically sensitive and we are building a Sprinter van into a camper. Are there any spray adhesives/glues that would work to create upholstered side panels in the van? The process would be gluing foam and upholstery fabric to birch plywood. The example we saw used an upholstery spray adhesive.
John Plyler
Guess what I am reading?
Mary Travis
Did you get an answer to this question elsewhere? We’re in the same boat- looking for spray adhesive to upholster a headboard! I’m also trying to find foam alternatives, but latex foam is so expensive!!
Katherine M
I’ve come here trying to find the same info, regarding reupholstering my couch. Did yall find something good?
Michelle
We just recaulked under our undermount sink, shower and backsplashes with the GE Silicone 2. I am highly sensitive so we left the house for two days. Only a very slight odor upon return. Voc sheet says 3% 31 g/l. Not crazy about the mildewicide in it but I am happy no smell. Did I ruin my home’’s air quality by using this caulk or am I ok once it is completely dry? Have several health problems. Someone else suggested I use Chemlink clear but I would hate to rip it all out aince I tolerated it well. Thanks for yiur work and help!
Bee
Hello I need to re-attach some rubber to the bottom of a metal guitar pedal. I am looking for a kind of non-toxic contact cement. It needs to be able to be pulled off again, (the rubber), and reattached, etc. Thanks!
Dalton Bourne
Used this caulk from Dicor to install a couple of fantastic vents on our camper. The stuff that came off the old vents looked like it was this and some other kind of tough caulk. The tough stuff was almost impossible to remove from the rubber roof. One tube was enough to sufficiently install and seal the vent holes for two new units. We did a seam around the bottom of the fan lip before installing, around the lip, and cover the screw holes of the new units.
Mitch S
Hi Corinne!
We are having new quartz countertops installed. The the glue we are using AFM Almighty and for the caulk we are using AFM Safecoat.
The installer is saying that he needs to finish by wiping the countertops with acetone. I assume to clean up caulk residue? How dangerous is this? Are there alternatives you might recommend?
Thank you for your help!
Mitch
Corinne
They don’t need to wipe the countertop with acetone, in fact they can damage the quartz.
Fred Christen
As a quartz fabricator for 22 years, we do use acetone at times to remove adhesive but denatured alcohol can also be used and we prefer it because it will not damage the finish on most cabinets if dripped. Neither acetone or denatured alcohol will damage your quartz countertops.
Susan
Hi. I can’t find a safe alternate to trim hold. Glue for a 4 way stretch material for a camper van
I’m scared as the tin says suspected of causing cancer
Please help
fridayrack
Ecobond is absolutely having a few issues right now with getting orders out and with their different providers. This has occurred previously, individuals habitually say or think they are leaving the business. I don’t know what’s going on.
dalebert MSEE
Have you researched PVC-E glue? It appears to be a thinned acrylic adhesive/caulk. It is recommended by the piano folks. They seldom mention the ingredients.
I use hide glue made from gelatin, but for quick and convenient wood repair I use Titebond. An amazingly strong bond is the thin CA over baking soda (or some other powders, even wood ash).
Excellent article.
Corinne
I’m not familiar with glues used in specialty items like instruments, art, crafts etc
Kristin
Thank you for the very helpful post. Wondering if you could tell me what you think about DAP silicone. I don’t have chemical sensitivities, but do have young kids and generally try to use non toxic products in my home. I need to have my bathroom tubs and sinks re-caulked as well as the caulk connecting my backsplash to my kitchen counters. AFM as well as Durasil are on backorder wherever I look. My handyman uses DAP. I see it has phthalates, but is allegedly low VOC. It seems to compare similarly to the GE sillicone caulk you recommend (which has petroleum distillates)? I know both have mildewicide. Would you recommend one over the other, or do you have other suggestions that are available now and would hold up well in humid conditions? Thank you.
Corinne
Check out the video that is in the post it gives the best overview with options available right now.
Adriana
Hi Corrine. I am new to the no toxic world. I was going to use AFM to caulk the area around my tub that meets the wall tile. However it seems to be on back order. Can Novolink 35 be used for this and do you know if they have pthalates in their product?
Thank you!
Dian
Do you know if this is a good product – did you test this one?
https://www.henkel-adhesives.com/us/en/industries/engineered-wood.html
Joanna
Thank you for your information. Could AFM safecoat be used for a kitchen sink in substitute of silicone?
SR
ASI388 vs DuraSil.
I appreciate your information greatly and was hoping for some further clarification.
ASI is an oxine cure caulk while DuraSil is neutral cure.
Do you have a preference for certain situations? Would Durasil be less toxic than wet than ASI, but overall ASI might be less toxic than Durasil in other situations?
Thanks
Corinne
Both are neutral cure.
Geneviève
DAP caulk is a godsend! It smelled only faintly while applying and the only time I smelled anything outside our bathroom was after a shower. I would not even be scared to use it in the middle of winter!
I looked through the data sheets of all the products you mentioned that I could buy locally and I found the one I wanted to try (DAP 3.0). The data sheet VOC number was 10 times lower than any other I’ve found. I still tried to check on the bottle before buying but I’m really happy I still bought it even though there is no VOC information on the bottle.
Corinne
Interesting, I wonder if that one is secretly a polyether! I have emailed them. thanks for the tip.
Shannon Buffo
Dear Corinne, Thank you for all your diligence in providing this much need website for us SMCS(severe multi chemical sensitive – ME) Quick question: Since I am at my most severe chemically sensitive, primarily effected by odor of any kind, I am looking for a baseboard caulk that when dried has absolutely no odor. I know there is offgassing for possibly one or two weeks. Can you please recommend the only one you would use in my situation. I am so severely sensitive everything I use is fragrance and scent free. Thank you! Shannon
Corinne
I responded on Facebook to your question, that you might not be able to go with one of the paintable caulks. Only you will know once you test them.
cari
Very interesting about DAP 3.0 – my contractor had been using DAP Kwik Seal in the
bathroom, and just used it (without my permission) on the bedroom baseboards. I
don’t smell anything, but really not happy that it’s in my bedroom. It’s showing 28.3
VOC on whatsinprodcuts.com. Corinne, should I make him rip this out of the
bedroom? It’s acrylic based? Thanks, love all your work and this website!!
Corinne
you don’t need to remove it if you’re not reacting to it
samie
what type of sealant could i use for installing plastic skylight on a mobile home with shingles that is talc and asbestos free
Corinne
Go over the installation instructions, there isn’t necessarily caulk involved. I would not avoid talc in caulk though which is not in powder form.
Robert Hogward
Great article! The sealant’s overall performance depends on its formulation to provide a durable and elastic bond for the needed cure. Each product is formulated for permanent results or temporary bonds to ease future use.
Alison
Do you have any experience with PL Premiim? It says “VOC compliant” whatever that means. See https://www.homehardware.ca/en/825ml-paintable-pl-premium-multi-purpose-construction-adhesive/p/2030590
Thanks
Corinne
That’s a polyurethane, those are high in offgassing compared to other types.
Mariana
Hi Corinne,
I went to the link for the Hide Glue because it was written that it was all natural and the California chemical warning was attached to it. Just thought you should know!
Corinne
That is not supposed to be there. It’s just something that they have on their product pages but it doesn’t apply to the hide glue flakes.
Jumana
Thank you so much for all your due dilligence Corrine! What brand of adhesive would you recomend for an entire solid wood-concrete floor? I saw your recomendation, but am wondering if there are any that would provide sound protection due to flooring being in a condo. Thank you so much for for your help.
Audrey
What do you recommend for an exterior caulk that can be painted? Itll be around a window, so needs to be very water resistant.
Corinne
There isn’t much choice there.
Devin Whatley
Hi Corrine, are you still available for consultations? I tried booking something through your website, but it doesn’t show any availability. Can you please contact me directly?
Corinne
I’ve updated the booking calendar https://app.acuityscheduling.com/schedule.php?owner=19257501&calendarID=4352774
Kathy
Thanks so much Corinne for helping MCS sufferers, builders and home renovators to be safer! I’m researching caulking/sealants for my 13 year old builder/maker (family history of allergies & asthma). Seems none of these products are risk free and while a sniff-test can help detect potentially harmful VOCs, little or no smell doesn’t mean something’s safe or no longer off-gassing!
This online guide to “building clean” lists POLYETHER sealants/caulks within the middle tier of those containing hazardous materials based on their inventory of typical products and their contents. Of course, not every product in a category will contain the chemical(s) of concern in them, so perhaps the AMF Safecoat Caulk is a safer version? https://buildingclean.org/sealants-and-their-toxins
The site says this about ms polyether sealants: “There is a common assumption put into product advertising that MS polyether sealants are healthier than polyurethane or butyl caulks because they are solvent- and isocyanate-free. However, most MS polyether sealants contain a lot of phthalate plasticizer—about 19 percent by weight. They also use UV absorbers and catalysts that are persistent bioaccumulative toxins.”
Kathy
Corinne
That article is a little bit misleading in a few ways. One part spray doesn’t usually have FR, only some lines do. Silica is only a health/cancer risk in dust form which is not the form it is ever in in a caulk or sealant. Same with titanium dioxide, you would have to breathe that in (or many ingest it though it is in many foods and pills too though that’s not ideal, we would not injest caulking).
Out of the paintable caulks used inside, both acrylic and polyether can have plasticizers. Phthalates are being phased out of most products now but you could ask AFM about that.
Polyurethane caulk and butyl are not a replacement for acrylic or polyether caulks (in the interior places you would need those) so the comparison is a bit confusing.
The offgassing from polyurethane and butyl is quite harsh, but they are usually used outside.
Cindy
I need to caulk the bottom of my tub surround. What product would you recommend for someone chemically sensitive? Thank you!
Corinne
Silicone is usually used if it’s not interfacing with a painted surface. AFM caulking for interface with painted surface.
J
Great article..do you know of any low voc glue that can used in jewelry making to attach to metal..e6000 glue is brutal..and alenes is awful doesnt work ..needs to dry clear..thanks…also..worth mentioning alot of the brands by chemical free companies caulk dries up much faster than others so it needs to be used right away once opened or even stored..i had multiple expensive ones go rock hard bad within couple months pf purchase..they have only several months from manufacture..thanks
Crystal Bryshun
Hi Corrine,
I am curious what you used on your tiny house, or have found a replacement for acoustical sealant for vapor barriers? some kind of a non toxic substitute ?
Corinne
I would intello plus in most conditions or similar product – depending on what the architect specifies. It’s installed with tapes.
Deborah Smart
Are these products Canadian, or available in Canada, other than the one where you listed the availability as a Canadian store?
Corinne
It depends on which product. Some are at the hardware store, some like AFM you have to order from Green Design Center.
Lee X C
Hi, Corinne. Thanks so much for your work! I am looking for information on no- or low-VOC expanding spray foams, preferably in a small aerosol can. Have you researched those products?
Corinne
Hi yes, they are in the insulation post. I use Greatstuff and I think they are all very similar. Though there is one that has some certifications
Heather Cook
My mom is having her basement redone and has been bed bound with copd and asthma for nine years. She is VERY sensitive to ANY smell. The basement will have a bathroom in it also. She is asking me to help her find out what kind of sealant or caulking would be Zero VOC and have no odor and not have titanium dioxide (which she thinks is harmful for asthma breathers) and can be used everywhere? Can you please help me!!!
Mike
Please note The Original Gorilla Glue is highly carcinogenic. I just found this out when diagnosed with a type of blood cancer that is only possible after exposure to toxins. I live and organic fed, wifi free toxin free life surrounded by fresh air. I just found out that the vapours from this glue are highly carcinogenic and I’ve been using it for years to build beehives for prolonged periods of time. If you read the small print; you are supposed to wear a mask (product info. doesn’t tell you which type will shield you), goggles, gloves, protective clothing etc etc. I have never worn a mask or goggles whilst using it for days on end. Non of this is obvious from the packaging and no one told me this at the store where I bought it. I just felt I should flag this up since it should NOT be listed on this site as non-toxic. It is highly toxic to the user, the environment and often kills dogs who eat it because it apparently tastes similar to peanut butter and maple syrup. It is activated by the water inside the animal and expands blocking the gut. Definitely one to avoid IMO.
Corinne
Wow. So sorry to hear that. This one is a polyurethane which will offgas isocyanates before it comes to a complete cure. Isocyanates are classified as potential human carcinogens and known to cause cancer in animals. They are in a lot of “non-toxic” products, like polyurethane wood finishes. They can be expected to cure within two weeks in many causes and stop offgassing. But working with the product all the time would definitely be an exposure.
Hanna Tatrzanska
Many thanks for your wisdom and noble comment. It is very sad that you are suffering from lack of warnings. In fact, this page should only contain products that are safe for us.
Corinne
Hanna, it is not possible to build a house with only all natural safe to sniff when wet glues, caulks and construction adhesive. I give information without judgement on what people should choose to use. You have to exercise your judgement.
Deborah Seely
Hi, I find myself in an emergency where I will have to have a bathroom sink replaced in my apartment, so I started researching caulking that is safe and came here. I wanted to let you know about a discrepancy I found on your information about the GE1 caulking. I noticed that both the GE 1 and the GE2 silicone caulking claim to have a “mold free warranty” on them. Curious, I looked up both products’ safety sheets and didn’t find any chemicals listed that are biocides of any kind. But the claim to have mold free warranties was disconcerting, so I called the company’s product question line. The man on the other end looked up both products and said that they both DO contain mildewcides in them and when I asked he checked all of their silicone sealants and they all contain mildewcides. I mentioned to him that the safety data sheet did not list anything like that, to which he replied that the product sheet might have listed the mildewcides on the consumer products, but that they don’t always have to list them. On the products that they sell to builders or contractors they list the mildewciteds but not on the stuff that regular folks like you or I buy. So, if you were going by the product safety sheet to determine the use of any kind of biocide, be aware that they may not list them. I ended up ordering the GE2 sealant because of its claim to off-gas sooner. Your review did help me, I just thought you would want to know about this issue.
Corinne
Thank you. I will check that again. It’s always been used as the aquarium safe one of the two. They might have changed it, or maybe they have more than one GE1. I will update that as soon as I can, thanks for letting me know!
Michael
While these products are all low in VOCs, there is another critical concern. Do any of these products NOT cause cancer? Do any of these caulks satisfy the California Proposition 65 certifications for not having cancer-causing materials?
I can’t even find – in many Google searches – any caulk that does not have the warning on the label:
CALIFORNIA PROP 65 WARNING: This product may contain chemicals known to the State of California to cause cancer, birth defects or other reproductive harm.
Thank you!
Corinne
yes you will find nuetral cure silicone like the chemlink durasil that don’t have any prop 65 chemicals. Between a neutral cure silicone and the less toxic polyether options you can get all interior caulking projects covered.
Michael
Thank you so much for your reply and your great article, Corinne. So just to make sure I’m clear, it sounds like for caulk, AFM Caulk and ChemLink DuraSil would meet Prop 65 as well as be low in VOCs. And in adhesives, AFM Almighty Adhesive. Much appreciated!
Unknown
You sound brilliant! How about a non toxic sealant for a 120 sq ft butterfly house?
Harry
The white adhesive caulking made by Eco Bond did not perform well for me in outdoor applications. It broke down and disintegrated after a few months! The clear adhesive sealant was amazing! The best product I have ever used. Unfortunately this company is out of business but is still taking orders but not sending out products. If you order from them they will charge your credit card but you will receive no product. You can verify this via the Better Business Bureau. I hope this helps someone.
Tina Marie
Did the EcoBond mold quickly? I've heard complaints it didn't last more than a few months.
Kristen Killebrew
thanks so much! will try the safe coat adhesive too!
Meri Rohaman
If you are accomplishing wood on the concrete slab attempt to find a formaldyde-free plywood.
Frank Lange
The safest toxic free adhesives and sealants are ECO-BOND http://www.ecobondit.com
They make a toxic free alternative to every product for caulking, adhesives, and silicone
mark1spot
I agree with Frank, and I suffer mightily from MCS. I did a side-by-side simultaneous comparison between Almighty and another AFM Safecoat product vs. ECO-BOND Multi-Purpose and Kitchen-Bath-Plumbing. For me, ECO-BOND products were less offensive, both initially and after 24 and 48 hours and beyond. Both companies' products worked fine in terms of their intended use.
Corinne
thanks for the info!
Antonio Chiarenza
where did you get eco-bond? I have tried to order it, repeatedly, through homedepot.com and it doesn't come. they and I have followed up with the manufacturer, who never answers the phone and doesn't return messages. very frustrating. looks like a good product but we can't keep waiting: you don't want to know how long it's been since I've had a shower! with summer coming baths just have no appeal. would like to try it but if we can't get it soon will probably go with one of the 100% silicone caulks.
wondering if anyone has tried gorilla adhesive and or gorilla 100% silicone sealant/caulk? they may be newer than this article. I thought of them because I was ok with the original gorilla glue. I actually found your excellent reviews here by searching for more information on the voc content of those gorilla products.
thank you for sharing your test results.
Paul
Antonio, I just ordered directly from eco-bond. All the other places I checked didn't have it for sale anymore.
Jt
I saw on the better business bureau that ecobond is commuting fraud… charging people for orders, printing/preparing shipping label but then not mailing product. They are also overcharging people by hundreds. Makes me so sad because we love their product!:(
The Multiple Chemical Survivor
I think I found my answer in your blog…on another post you mention RCD #6 Mastic. This is less toxic than what they would normally use?
Thank you so much for all your expertise on safe construction!! You are a life saver!
The Multiple Chemical Survivor
Hi Corinne…Did you by any chance test mastic sealant? I need to have my heating ducts inspected and sealed and they say it's required by law to use this stuff, but there must be a safer alternative. It is supposedly best because it's flexible, but it also offgases methanol, ethylene glycol, and ammonia. I fear I'd be homeless if they use it…You have so much experience with all your experimentation I thought you might know.
The Multiple Chemical Survivor
Holy Toledo you are a brave soul! Thank you for your sacrifice and for your information.
Corinne
ooooh god…yeah you know how it is! not a sacrifice though…I had to do it, the builders needed answers and NOW!
mark1spot
Corinne: Thank you so much for the specific product reviews and recommendations for MCS sufferers (like me) and builders!!!
Unknown
You are a brave lady for doing all that testing. I have to have two window panes installed and it has to be caulked and I couldn't find any at all. I will be able to now have those windows fixed and keep out the cold air.
Michael
While these products are all low in VOCs, there is another critical concern. Do any of these products NOT cause cancer? Do any of these caulks satisfy the California Proposition 65 certifications for not having cancer-causing materials?
I can’t even find – in many Google searches – any caulk that does not have the warning on the label:
CALIFORNIA PROP 65 WARNING: This product may contain chemicals known to the State of California to cause cancer, birth defects or other reproductive harm.
Thank you!