Practical, inexpensive, and has many uses for your health and around the home — no wonder tea tree oil is hailed as a "jack of all trades" among nature's herbal oils. Here's what you need to know about tea tree oil.
What Is Tea Tree Oil?
Tea tree oil (TTO), also called melaleuca oil, is made from the leaves of the tea tree plant (Melaleuca alternifolia), a member of the myrtle tree family, which is native to Australia.
The name was coined by British explorer Lieutenant James Cook in the 1770s, when he saw native Australians brewing tea using the leaves from the tree. Later on, he brewed his own batch of tea, and gave it to his crew to prevent scurvy. 
The tea tree plant is highly prized by primitive Australian communities for its unique healing ability.
Numerous aboriginal communities along the east coast of Australia have a long historical use of tea tree as an antiseptic for skin conditions. They simply crushed the tea tree leaves and applied it to cuts, burns and infections.
It was only in the 1920s, after Arthur Penfold,  an Australian state government chemist, published a series of papers on tea tree oil's antiseptic properties that this oil's benefits became widely known.
Through modern distillation methods, manufacturers are now able to produce tea tree oil with a clear to very pale golden or yellow color, and a fresh, camphor-like scent. 
Uses of Tea Tree Oil
Tea tree oil has been long valued for its antifungal, antibacterial and antiviral properties. In the 1920s, it was used in dentistry and surgery to help clean wounds and prevent infections. 
Surgeons believed that it is more effective than carbolic acid, the commonly used antiseptic at that time. 
Tea tree oil's has become more popular within the last few years, and it is now added to soaps, shampoos, lotions and other personal care products. Tea tree oil has many uses around the home, too. An article in Mother Nature Network  lists nine home uses of tea tree oil, including:
- Toothbrush cleaner — A drop of tea tree oil can disinfect your toothbrush, which is a breeding ground for mold and bacteria.
- Mold treatment — Mix a drop with a cup of water, spray on moldy areas and then wipe clean. For an all-natural disinfectant, you can also sprinkle a few drops of tea tree oil along with baking soda on your bathroom or kitchen surfaces.
- Natural pest control — The strong smell of tea tree oil naturally repels ants and other insects. I recommend making a natural insect repellent by mixing a few drops of tea tree oil with coconut oil.
- Laundry freshener — Adding a few drops of this oil during the wash cycle will make your laundry smell crisper and kill organisms lurking in your washer.
There are over 100 components in tea tree oil, but it is mostly made up of terpene hydrocarbons: monoterpenes, sesquiterpenes and their alcohols.  Light, heat, exposure to air and moisture can affect TTO's stability, so make sure to place it in an airtight container and store it in a dark, cool and dry place.
Benefits of Tea Tree Oil
Tea tree oil has gained a reputation for being an all-around remedy, from removing makeup  to treating warts.  Numerous studies have been conducted to prove the potential benefits of tea tree oil for health ailments, such as:
- Acne — A comparative study published in the Medical Journal of Australia  found that TTO and benzoyl peroxide both had a significant effect in ameliorating patients' acne. Although the onset of action in tea tree oil was slower, it caused fewer side effects than benzoyl peroxide.
- Fungal infections — A study published in the journal Tropical Medicine and International Health found that treating toenail onychomycosis with 2 percent butenafine and 5 percent TTO in cream cured 80 percent of patients.
- Bacterial infections — A 2004 study  funded by the National Center for Complementary and Alternative Medicine (NCCAM) found that TTO may be used as an adjunctive treatment for wounds, and may even help treat severe infections like methicillin-resistant Staphylococcus aureus (MRSA). However, large, well-designed clinical trials are lacking, and the jury is still out on whether tea tree oil really has this potential.
Tea tree oil is said to be helpful in alleviating chest and head congestion, stuffy nose and other symptoms of colds and fluIn aromatherapy, tea tree oil is said to be helpful in alleviating chest and head congestion, stuffy nose  and other symptoms of colds and flu, especially when used in steam inhalation.
Steam inhalation clears the congested nasal passages and kills bacteria.
Adding an antiviral essential oil like TTO makes it that much more effective. Just add a few drops to a steaming bowl of hot (purified) water, cover your head with a towel and breathe in the vapors for five to 10 minutes. Adding a few drops of tea tree oil to your bathwater may also help stop a cold from developing. 
How to Make Tea Tree Oil
Large-scale tea tree oil manufacturers use steam distillation to extract the product.  But if you have fresh tea tree leaves on hand, you can easily make this oil. Here's a step-by-step process from OfftheGridNews.com: 
Put the leaves in a pot and cover with water. Place a vegetable steamer in the pot over the top of the leaves and water.How Does Tea Tree Oil Work?
Put a measuring cup inside the steamer.
Place the lid on the pot upside down, so that the handle nub in the center is pointing toward the measuring cup.
Boil the water to steam the leaves. The water will condense and evaporate, and the condensation will slide toward the handle and into the measuring cup.
Put about four ice cubes on top of the upside down pot lid to hasten the steam condensation.
Turn off the heat once all the ice has melted.
Take off the lid and pour the ice cube water into the sink, and then remove the glass measuring cup.
Pour the measuring cup contents into a separating funnel, but make sure the stopcock at the bottom of the funnel is closed. Close the top of the funnel and shake vigorously.
Invert the funnel and then open to release the pressure. The oil will float to the top of the water, effectively separating the two substances.
Put a glass bottle beneath the stopcock and release the water. Pour the oil into a tinted glass bottle.
Repeat the process up to three more times to pull more oil from the leaves.
The chemicals in tea tree oil may help kill bacteria and fungus and reduce allergic skin reactions. Experts believe the most beneficial component of tea tree oil is its high terpene content. According to Dr. Aurora DeJuliis, a dermatologist and aesthetician based in New Jersey, terpenes are a type of volatile oil that has been shown to destroy bacteria. 
However, I advise you to use tea tree oil with caution — it's meant to be used topically. Some mouthwash or toothpaste products contain tea tree oil but are generally safe, as they are not swallowed.
Using tea tree oil at full strength can cause skin irritation, which is why it is often diluted with other natural ingredients, like raw honey or coconut oil. Different treatment options also call for different percentages of tea tree oil. For example, acne treatments only require 5 to 15 percent TTO. For fungal infections, 70 to 100 percent TTO is used. 
Is Tea Tree Oil Safe?
The answer is yes, as long as it is applied topically in appropriate doses and NOT swallowed. This oil may irritate your skin, especially if used for the first time. I recommend starting with low concentrations until you figure out your tolerance.  It's also a good idea to determine if you have an allergy to tea tree oil before using it. Apply a small amount to your inner arm to see if any reaction occurs. 
The NCCAM recommends avoiding oxidized oil, which has been exposed to air, because it may trigger allergies more than fresh tea tree oil.  Avoid using undiluted tea tree oil to avoid irritation as well. Instead, use it in gel, cream or lotion form. Look for an all-natural topical product that incorporates tea tree oil in safe quantities.
Risks of Tea Tree Oil
Tea tree oil contains varying amounts of 1,8–cineole,  a skin irritant that may cause allergic reactions in some individuals. The rashes are usually mild and itchy, but may also lead to blistering. Serious allergic reactions may also occur. DO NOT swallow or ingest tea tree oil. It may cause severe reactions, such as rashes, blood cell abnormalities, diarrhea, stomachache, nausea, vomiting, drowsiness, hallucinations and ataxia (loss of muscle control in the arms and legs). 
Tea tree oil may also be toxic to pets if ingested. Veterinary toxicologists found that large amounts of undiluted tea tree oil applied to the skin of cats and dogs caused a hypersensitivity (allergic) reaction.  If you are allergic to eucalyptol, use TTO with caution, as many formulas are mixed with eucalyptol.