Why Does WD40 Kill Bugs?

Because of the solvents and other noxious things in it.

Material Safety Data Sheet (MSDS) - WD40.com

WD-40, although I wouldn't want to breathe or drink it, it is one of the few such fluids to be allowed into just about every country in the world.

WD-40. HMIS Hazard Rating: Health – 1 (slight hazard), Fire Hazard – 2 (moderate hazard), Reactivity – 0 (minimal hazard)

Marvel Magical Oil for example, used often in similar circumstances in the USA, due to its seriously carcinogenic nature, is naturally totally banned in most civilized countries.

Marvel_Mystery_Oil-MSDS.pdf

HAZARD CATEGORIES

Acute Health Yes, Chronic Health Yes, Fire Yes, Reactive No.

Just so you all know, its not meant as a competition!! But as information!!

There are other similar oils around with other names and ingredients.

I guess the US isn't civilized enough to have banned it, you can buy it anywhere. Its MSDS is similar to WD-40.

I just posted the health hazards from both MSDS, they are significantly different.

Furthermore the customs and excise in many countries, for the poisonous nature of MMO, will not allow it. But WD-40 IS allowed.

MMO damages many types of plastic, whereas WD-40 does not! This video mentions that! MMO Damages Plastics

The people who ban it are not stupid. If you look up some of the ingredients, it might raise the hair on the back of your neck....

I even found, a video on YouTube, with some Guy with his hands in a pool of MMO, saying just how great it was!!

Using MMO in aircraft engine fuel, allowed by the MMO company, brought that aircraft down at takeoff with MMO with catastrophic engine damage!!! They have NEVER lived that one down.....

The lubricant was used as a fuel additive in a Lycoming aircraft engine which was specifically cautioned against oil additives (Service Instruction No. 1014M, which also stated its use would void the warranty) which suffered catastrophic damage during take-off. The NTSB listed the probable cause of the accident as "The improper use of [a] fuel additive which resulted in a power loss."

See here:- Marvel_Mystery_Oil

Check the ingredients out carefully, they are listed on that weblink!

According to the company's 2015 safety data sheet Marvel Mystery Oil is composed of:^[2]

• Petroleum Distillates (Hydrotreated Heavy Naphthenic) also known as mineral oil, 60-100%^[2]
• Petroleum Distillates (Stoddard Solvent) also known as white spirit, 10-30%^[2]
• Tricresyl phosphate, an antiwear and extreme pressure additive in lubricants 0.1-1.0%^[2]
• Ortho Dichlorobenzene, a softening and removing agent for carbon-based contamination on metal surfaces, 0.1-1.0%^[2]
• Para Dichlorobenzene, a precursor used in the production of chemically and thermally resistant polymers, <0.1%^[2]

A Marvel Mystery Oil sample tested for an NTSB post aircraft accident investigation published in 2003 found it to be composed of 74 percent mineral oil, 25 percent stoddard solvent, and 1 percent lard.^[3]

This discrepancy has not been resolved.

Its best NOT to take risks with anyone's car engine either....

Remember, its a product designed after WW1. It has simply outlived its usefulness...

WD-40 was designed to protect Rockets from corrosion in the 1950s I believe. We RNers, used it to clean and protect all the equipment and the fuselage on our RN Helicopters...With amazing results.

I hope this clears up any misunderstanding. Naturally, its your personal choice to use it or not, I just wanted to give you an educated position from which to decide....

I was simply countering your argument that it is banned everywhere, especially since there is no published info to back that statement. It is banned in aircraft engines (just like Slick 50 was), but so are most additives that are not specifically designated by the manufacturer. Same for car engines, it's just the manufacturers' way of limiting their liability.

I used to use the recommended 1/4oz/gal mix as top oil in my GM and Jeep engines; they ran quiter with a small 1-2 mpg improvement on the highway, and no plug fouling (yes, I kept records).

I'm not a chemist/chemical/environmental engineer, so perhaps you can explain why you honed in on Stoddard solvent as a danger, since it's commonly found around the world in many paint products under its more common name, mineral spirits. In Europe 60% of its production goes into varnishes, lacquers, and paints.

Welcome back!

Which is great, I like a good discussion.

The original oil, after looking on ebay Germany, ebay UK and the ebay USA, only comes up as being located in the USA!

There are some later products with the same name that do come up though, but not the original....from 1923!

Sadly, I could not substantiate my findings to the standard I would wish myself....Google was uncooperative!

I showed all, but its not the Stoddard that is dangerous its some of the others.....

1,2-Dichlorobenzene

Safety

Data from human exposure to 1,2-dichlorobenzene shows that concentrations of 100 ppm have been reported to cause sporadic irritation of the eyes and respiratory tract.^[7] The Occupational Safety and Health Administration and the National Institute for Occupational Safety and Health have set occupational exposure limits at a ceiling of 50 ppm, over an eight-hour workday.

The United States Department of Health and Human Services (DHHS) and the International Agency for Research on Cancer(IARC) have determined that p-DCB may reasonably be anticipated to be a carcinogen.^[7] This has been indicated by animal studies, although a full-scale human study has not been done.^[8]

Tricresyl_phosphate

ricresyl phosphate, abbreviated TCP, is an organophosphate compound that is used as a plasticizer and diverse other applications. It is a toxic substance that causes neuropathy through ingestion, and has been the cause of several mass poisonings in history. It is a colourless, viscous liquid, although commercial samples are typically yellow. It is virtually insoluble in water.

Happy now?

Your example of an aircraft suffering engine failure after using MMO is in error. You state that MMO was used as a FUEL additive, then quote the service bulletin that warns against using it as an OIL additive. I followed your link, which led me to the NTSB acident report. Not really very convincing. The operator of the banner towing operation said that MMO had been used, but nobody actually admitted to adding MMO to the fuel. A one gallon can was found in the trash at the hangar. It was thought that a full gallon was added to one of the 18 gallon fuel tanks, which gives about a 6% concentration--far greater than MMO used to recommend. There was NO laboratory testing of the fuel to determine if MMO was actually present, only the color of the fuel was reported as 'pink' and it 'felt oily'. It should be noted that 80/87 octane avgas is color coded red or pink. The fuel in the other tanks was blue, indicative of 100 low lead fuel. It should also be noted that the pilot and the FAA investigator reported different fuel tanks had the red colored fuel. The engine did NOT fail during takeoff, rather the banner towing plane was in level flight at 1200 feet and the pilot switched fuel tanks prior to the engine gradually losing power. Post-accident examination of the engine showed that all four exhaust valves and two intake valves were leaking. Piston damage indicated possible detonation. I don't know that MMO would cause valve failure or sticking, in fact, it's used to cure valve sticking. Likewise, I don't know that it would cause detonation, but at 6% concentration, it may.

Just so you know, my father used to sell barrels of MMO to the airlines. They were the largest user of MMO. This was some time ago, they used it in radial engines on DC-3s, etc. If an engine ran rough during the pre-takeoff run-up, they taxied back to the hangar and put in a couple of gallons of MMO. If it ran well, they flew the trip.

Since you bring up aircraft engines, I assume that you're aware of the fiasco that Mobil had when they introduced their full synthetic oil, AV-1. Turns out that it was not compatible with the leaded fuel used in airplanes and cause massive sludge build-up in oil galleys and a lot of engine failures. Mobil paid to overhaul thousands of engines and the FAA banned the use of synthetic oils in aircraft.

I've used MMO in my airplane on occasion, as well as in my cars, though not on a regular basis. It quiets hydraulic lifters.

While I appreciate your 'educated position from which to decide', I think you're an idiot. For some reason, you seem stuck on WD-40. I still have the first can of that crap I ever bought, about 40 years ago. It's not good for much, only displacing water and, now, killing bugs. It's a lousy lubricant, and it dries out causing a sticky mess if left in place.

I'll keep on using MMO, even if the 'smart people' of Europe have banned it. What do they know?

Apparently I neglected to post the link with all the full details that I based my post on, so here it is:-

Marvel_Mystery_Oil

That should answer all your queries and prevent any flare up on your side!

But if you have a "beef" with the quality of the details on Wiki, please take it up with them, not me.

On the can it says "add to gas and oil" by the way......!!

Add to Gas and Oil!!

Now if you REALLY love the stuff, try this:-

This link may be of further interest:-

National Transportation Safety Board

Remember, I would not touch the stuff with a barge pole, nor would I bring it into my household!!

Furthermore, some of the components, shown in the MSDS, supplied by the company, are considered dangerous and very carcinogenic, pointing out that in 1923 such dangers were probably largely not understood, and even if they were, laws protecting people were probably not in place or inadequate......

That alone, even if it was allowed to be imported (its a forbidden product in most civilized countries), would make me very wary about using it.

Do you yourself know what warnings are actually printed on the product itself?

As far as I can tell from online pictures, none! So apparently the company is a bit "fast and loose" with the health of families with the product in their homes and garages....To my mind, its a bit like a time bomb!! A child could find it in the family garage, incorrectly stored.

I do believe that the same company produces other products under almost the same name, which are of far less danger to human life.

Remember I am only talking about the original product, not the later one(s), but it would not be a problem to do that too if you feel its necessary!

I trust that we can consider the matter closed, as no "cross Atlantic" argument will change anything at all. Understood?

I wish you a pleasant day.

Other lnks of possible interest:-

https://www.pilotsofamerica.com/community/threads/marvel-mystery-oil.54533/

http://www.cessna172club.com/forum/ubbthreads.php?ubb=showflat&Number=6027

https://www.eng-tips.com/viewthread.cfm?qid=97440

https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2033099

https://backcountrypilot.org/forum/marvel-mystery-oil-is-people-1745

A different opinion is interesting and valid when restricted to technical comment and backed up by independent sources - but referring to Andy G as an 'idiot' for saying something you do not agree with is not helpful - and negates the GA you got.

.... and as for the OT to Andy G in #41 .... a bit of a coincidence.

He wants to have an argument about an oil that even in the MSDS is labelled dangerous.....

It was formulated in 1923, probably before "health and safety" was much regarded.....

Some of the constituents are regarded today in a very bad light, which explains why the original formulation is not allowed to be imported into many countries....

Many thanks for your pleasant post, his post not worry me in the least!!

As I always say, you can take a horse to water, but he must know how to drink!!

Have a great day everybody, I am!

It's mineral oil and fish oil. It's probably the safest bug spray ever made. I also use for cleaning the stainless in the kitchen because it won't harm the babies, fuzzy or otherwise.

I used to love wd40 for killing ants, it kills them instantly....It has saved me on many occasions...you can have thousands of ants and with one wave of the can, everything stops moving, it's amazing....and spray glue for wasps, it doesn't kill them instantly, but it stops them in mid flight and you can them stomp them....Facing a wasps nest on an electrical panel that you need to access is no longer a problem if you have a can of spray glue...Never really tried wd40 on roaches, I mean who cares if they die instantly, I actually prefer they crawl out of sight to die, Black Flag odorless is my choice in the house, I hate any noxious odors in the house...this rules the wd40 out for use indoors....and spray glue also for obvious reasons...bugs are best fought on the outside perimeter of the house...

Well I don't think you can kill anything that fast, unless you squash them, so it must paralyze them instantly, and then they die peacefully...

you should try it on ants.....

Reminds me of my ex-wife, she wanted to help when I rewired our first house. I set her to nailing down the floorboards on the first floor. There was a scream “a spider”, “you’ve got a hammer kill it”. She did kill it and also broke the floorboard for good measure.

It was well and truly dead!

LOL, with fear comes the strength of ten men....haha

Purity is a scourge to weakness...

get a room you guys!

did you spray your ex-wife? did it work? would you admit to it?

I often just reach for the nearest spray can of chemicals in my garage when I need to kill a critter. Brake parts cleaner, gunk engine cleaner, PB Blaster all kill bugs on contact better than the products designed to do the killing.

Remember, WD-40 is not a lubricant. It is a water displacement fluid.

Edited for clarity⇓

MSDS:- Composition/Information on Ingredients

Weight Percent Aliphatic Hydrocarbon 45-50%

Petroleum Base Oil <25%

LVP Aliphatic Hydrocarbon 12-18%

Surfactant Proprietary <2%

Non-Hazardous Ingredients Mixture <10%

10 Facts about Aliphatic Hydrocarbon Solvents | CCC Chemicals ...

Suggesting that WD-40 won't harm "plastics" is not exactly a statement I can support.

You are 100% correct.

It gets used to free stuff up and displace water, and then some people forget to lubricate correctly....

Bad news!!

Odd, it seems to work well as a lubricant in my locks at home. Every autumn I "winterize" the house and garage door locks by spraying in some WD-40 and then work the mechanism until everything moves smoothly. Not only does this seem to prevent the lock from icing up in the winter, but the insertion and turning resistance drops to near zero.

If reducing friction by application of a fluid is not "lubrication," than I literally do knot know the meaning of the word.

From their website: "...and lubricates almost anything..." If it smells like a lubricant, acts like a lubricant, and is advertised as a lubricant, then it must be a lubricant!

It does work for that, but not recommended. The proper lubrication for a cylinder door lock is a dry lubricant that does not let dust stick to it. Usually a spray that you shake to get the crystals whirling around, spray into lock, transport fluid evaporates, leaves the crystals stuck everywhere.

In 2007 I worked for a Lock company that also made new cylinders, they would never use WD-40 or anything that remained wet. Door locks, depending upon design and relative air pressures in and outside a house, can have a draft of air through a lock....bringing dust as well. Not good.

WD-40 works quite well on modern window mechanisms, I would recommend it for that. A bit of dust does not stop the mechanism working. First 3 years a new window here is lubricated from the factory, I either use WD-40, or synthetic Bike chain lubricant. Both work well. Once a year after year 3.....

I consider the lubrication to be a secondary effect when winterizing the exterior locks.

The primary purpose of the WD-40 is to keep water out of the mechanism so the lock does not ice up in the winter. Two minutes spent working WD-40 into the inner workings in "moderate to pleasantly cool" weather is much better than spending 10-15 minutes trying to thaw the lock with a propane torch-heated key, while working in a blizzard in -40 degree temperatures⁽¹⁾, and wearing winter gear that is made of flammable synthetics.

Notes:

1. "Do you mean Fahrenheit or Celsius?" "Take your pick."

Then its probably better to lubricate often with WD-40 as you need to wash away any collected dust which is a problem with wet lock lubes.

Also, that is often the reason for excessive wear in what is quite a "fine" mechanism.

If your door is liberally doused with rain or water, though the dry lubricants seem to repel water well too....

My front door, even though when its minus 25°C outside, the indoor part of the lock turns white as it is frozen from the outside and we have it warm in the house with around 55% RH, the outer part of the lock turns easily. The inner parts also turns easily....Never had any problems.

Nor with any of the locks I service, including many car doors....

The front door lock is about 12 years old and I expect at least a further 12 years minimal.

Here is a picture of just one of many good products for keeping locks clean, dry and lubricated, there are many. The label says it all:-

pe·tro·le·um pəˈtrōlēəm/ nouna liquid mixture of hydrocarbons that is present in certain rock strata and can be extracted and refined to produce fuels including gasoline, kerosene, and diesel oil; oil.

If oil is not a lubricant, then what is?

The point was that WD-40 was developed as a water displacement fluid, NOT as a lubricant.

It is misused every day, apparently by those unaware of its primary function, such as yourself!

You're primarily a husband, but you do other things, don't you?

When I was a kid all I needed was a bic lighter and I had handheld bug killing 20 foot radius mini flame thrower.

Way more fun than today's perfumed bug sprays.

"Snap, crackle and pop" maybe?

(Rice Krispies Breakfast cereal TV Ad "Jingle" from the 50s and 60s!)

https://www.youtube.com/watch?v=q6TIsxTdrCU

For completeness, here's a list of over 2,000 uses for WD-40. The allegedly verboten words like lubricant, rubber, plastic, pvc, lock, etc. appear multiple times. I guess other people aren't afraid to find odd uses for it.

don't see.. Kills all known bugs and flying things!

2001 uses for WD40!

Let us all agree that its only temporary, short term lubricant. Not long term.

I know someone that freed a seized Knitting machine with it, but she forgot to use the right oil afterwards and it seized again a few weeks later.....

The first seizure was dirt and grime, the second was physical damage to several needles....far more expensive.

I love WD-40 for many jobs, usually have a few cans as I buy a new can when its on offer!! Great stuff.

Interesting. Will try it. So many bugs in my garage.

At last....

Thank you!

If memory is correct the WD in WD40 means water displacement and the 40 was the 40th attempt to produce the product.

You are completely correct....I recent read a short article on the history and development of WD40 and all I can say is ditto.

The comments are really helpful. I now understand.

You spray it!

The cans are great for walloping the bugs but I'll probably get more use by spraying.

Got a box full of WD40 cans all with damaged spray thingys and other damage.

tee hee

So true it seems that wd cans go dead (no Spray) often. I recharge them and other spray cans using a valve stem (new not hard and old). Simply take you air compressor at about 100 psi max and remove the spray nozzle push down on the top of the can with air chuck and you will force air into the dead can, which acts as a propellent . Very satisfying to recharge dead cans.

I saw this on Youtube. I wondered if it would work.

WD-40 displaces water so it can possibly do a couple things to the bug. first off, it can "wet" the bug (bypassing the veneer hair) and filling the ventricles (what ever they are called) that process oxygen, thereby drowning it. Second thought; It may also pull the water that is in the bug desiccating it.

Disclaimer: uneducated guesses.

Could the reaction of WD40 on insects maybe also relate to the solvents or propellants in WD40 dissolving the exoskeleton of the insect?

Just like using alcohol and "shellac" insects to make old time varnish.

Again, just a guess.

The oiliness. It's tempting to look at microadditives like TCP, but WD40 is an oil and I know that ants (and roaches) are zapped instantly by contact with peppermint and rosemary oils, as in Ecosmart. Entomologists and bugkiller makers can figure out the details as there are many materials that can be called Oils and that lubricate.