How Toxic is Tea Tree Oil?

Tea tree oil can be toxic 

Just because it's natural, or an herb, or used in aromatherapy, or has potential health benefits, does not mean it's safe for all uses.

You can read more about the safety of eating or drinking tea tree oil here. Please don't do what this visitor to Tea Tree Wonders has reported.

With 100% pure tea tree oil there is almost no risk of an allergic reaction when used properly on your skin, in a mouthwash or toothpaste, or on your hair.

I'd like to share
this e-mail with you....

Hi Jim,

Just a note to tell you a story of mine about tea tree oil...I had a fungal infection a few years ago (intestinal) and couldn't get rid of it, and finally I thought I would try swallowing tea tree oil for a while and see if it helped.
It tasted dreadful and I ate it by putting a teaspoon on a bowl of ice cream, it was the only way I could get it down...after a few weeks of doing this,I read a green pharmacy book which said it was toxic to the liver and don't take it internally...well I am still here, but it scared me (and didn't cure the infection by the way,) but I thought I would just let you know about that.
A lot of people don't know it is poisonous to take by mouth. Well, only an idiot would force tea tree oil down by mouth anyway...but there you are.

There is a ton of misinformation out there, including a few videos about ingesting tea tree oil, available online, that are giving out dangerous suggestions.

The idea repeated in the above letter is just one of them.

What Tea Tree Oil Uses Are Safe?

One use for tea tree oil that is safe is in the removal of head lice. As a topical or cosmetic application, the tea tree oil is used externally to get rid of the unwanted pests from children and homes.

Tea Tree Oil is a safer alternative to many other chemical lice removers including the highly toxic Lindane, now banned in may countries.

There are lots of products that are sold over the counter that are dangerous to human health, and many everyday products are suspected of containing cancer causing chemicals. The best means of avoiding cancer is to avoid the products that contain known carcinogens.

Since these days it is becoming increasingly difficult to completely eliminate such products from our daily lives, we should take responsibility for the things we do have control over. Choosing natural alternatives could be just one such solution.

How poisonous is Tea Tree Oil?

(or, how much will it take to kill me?)

Tea Tree Oil poisonings are fairly rare, but they do occur. However, there are more common oils and home remedies that are even more toxic. The most common is menthol, found in pain rubs, vaporizer gels and drops, cough drops, mouthwash, chewing tobacco, and a host of other products.  I have not seen any information to suggest even one human death from tea tree oil. 

The facts are, tea tree oil, like menthol, other essential oils, and many other substances, is graded on an LD 50 basis. This means, when tested on laboratory animals, the lethal dose needed to kill 50% of the animals is measured, and the results reported as LD50 at a certain number of grams or milligrams by weight.

Tea tree oil toxicity is equal to 1.9 g per kilogram, or about 1/5 teaspoon per pound of body weight. This is considered a lethal dose in 50% of persons or animals administered this dose.

For a 150 pound person, the LD 50 would be about 4.5 ounces of tea tree oil.

This is why, it is common for folks who are overzealous and uninformed or who have received bad information to poison their own pets, particularly small cats and dogs.

Tea tree oil is toxic to cats. An average cat weighs seven to 12 pounds, or between 3 and 5.44 kg.  If toxicity were based solely on weight, all things being equal, somewhere around 1 to 2 teaspoons of tea tree oil would be lethal to 50% of cats given that dose. Before you go putting tea tree oil on your cat or dog, please read this...

Warning for dog and cat owners whose pets have been exposed to toxic amounts of tea tree oil

In cats all things are not equal, and their liver is not capable of processing even smaller amounts of tea tree oil. Poisonings are frequent.

Because of this cats should never be treated with anything more than about five drops of tea tree oil per teaspoon of carrier oil. The same thing applies to small, and some medium-sized dogs.

Remember, this is for topical application only. Using a cotton swab or cotton ball only.

What should you do if a person or pet has consumed too much tea tree oil?

Call poison control. In the USA the phone number is


For cats you can read this article "Australian tea tree (Melaleuca alternifolia) oil poisoning in three purebred cats" by
K. Bischoff and Fessesswork Guale. It's a PDF file so you can either right click and save it to your computer, or simply open it to read the file.

You may need to use a PDF reader, which you can download for free from Adobe.com.

The article describes the treatment used to help the cats that were poisoned by skin contact with the tea tree oil. Ask your doctor if the same methods would be used for people as well.

Feel free to print the article out to take to your physician or veterinarian.

Are you concerned about less toxic living?

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