MAKE IT!

Materials

• 12-15mL (3/4 tbsp. to 1 tbsp.) of bleach

• 3-4mL (1.5 tsp.) of distilled white vinegar

• Water (500mL)

Tools

• Unused container that can hold around 600mL+ of liquid

• Lone chopstick missing its partner

• Spray bottle or anything similar

• [OPTIONAL] Litmus paper

DIRECTIONS

1. Put the bleach in the unused container. Add in the water (any kind is fine, even tap water) and stir with your singular chopstick so that the solution is even.

2. Take the whole container (bleach and all) outside or somewhere you can vent it, then add the white vinegar in and mix everything together.

• Do not make any more than one batch at a time! Mixing bleach and vinegar produces chlorine gas; the more you mix, the more chlorine is produced, and the more dangerous it is for you!

3. If you have litmus paper, you can test your liquids for the correct pH.

• Dipping litmus paper in bleach should show it's basic (turn it blue).

• Dipping litmus paper in distilled vinegar should show it's acidic (turn it red)

• The correct pH for this solution is anywhere from pH 6 - 7, which in our case was green. Follow the instructions attached to your litmus paper.

4. Pour the solution into a spray bottle, and then mist whatever you want with it! We've tested it in skin and on our faces. The cat didn't like the smell very much.

• When spraying it over someone, do it from above so that the mist falls down all over them.

• Have them close their eyes as well when spraying.

Recipe adapted from Patient story: wound treatment success with a homemade dilute hypochlorous acid solution

BACKGROUND

As a new virus, the characteristics of COVID-19 were difficult to nail down and were all over the place. With the limited information that we had on this novel virus, communities fell back on general spectrum solutions that could tackle and eliminate microorganisms of any kind.

Of course, solutions like this tended to be harsh: if they could eliminate all microorganisms, then they were likely harmful to us humans as well. Existing disinfectants balancing these factors have been applied, but ran out in many places. As such, we began to explore the idea of a disinfectant that was easy to produce both at home and in communities worldwide.

We originally explored the idea of anolyte-based solutions when we chanced upon this article here, which details the deployment of a portable disinfectant chamber in Hanoi. Similar solutions popped up across India as well, but industries were secretive with their recipes, and what went into these anolyte solutions.

In essence, anolyte solutions are made via electrolysis - in short, anolytes are just the liquid surrounding the anode in an electrolytic setup. When you electrolyse salt water, compounds are split apart and new compounds are generated - in this case, the anolytes have a lot of microbicides, one of which is hypochlorous acid. Read up on the Wiki here - it explains the chemistry relatively well!

However, the biggest difficulty in using hypochlorous acid is the fact that it doesn't like to keep that form. Its components simply prefer the company of other stuff if it can get to it. To keep it in this form, we have to keep the pH neutral. There's a lot of conflicting information, but the chemistry is explained pretty well on the Wiki (and on the articles it references as well).

How we got here, and why hypochlorous acid?

Hypochlorous acid, although not a household name, has been touted in multiple industries as an effective microbicide. In very minute amounts, it has been used in cosmetics, baby products, food service, and water treatment across the world.

There are multiple scientific articles from reputed journals as well, describing the beneficial effects of hypochlorous acid. Unlike bleach, however, hypochlorous acid seems gentler on the skin, and it was theorised across multiple sources that hypochlorous acid ia actually a better microbicide than bleach (the idea is that microbial cells are negatively-charged, the active ingredient of bleach - hypochlorite ions - are negatively-charged, so they repel each other, but the neutral pH of hypochlorous acid allows it to get closer to microbial cells and destroy it).

Our difficulty, as mentioned, is to figure out a way to make hypochlorous acid at all. It's an industry secret, or you have to read a lot of papers. There are some instructions from laypeople, but they're also conflicting and the explanations they provided were just as confusing. In the end, we narrowed down on a specific article: Wound Treatment Success with a Homemade Dilute Hypochlorous Acid Dilution, written by Angela Nolan for Wounds International 2016.

The article outlined the struggles of a patient of hers aiming to keep a wound disinfected while balancing cost and effectiveness, and is an anecdote of success. Crucially, however, it provides the exact recipe we outlined above:

"by diluting food grade bleach containing 1% sodium hypochlorite in the ratio 1:40, and then modifying the pH to around 4.5 using ordinary white vinegar, I could achieve a 0.025% HOCl solution with a pH that is compatible for skin health."

We followed the recipe, made a few notes, and then tested it on ourselves to make sure it was safe. Regular skin? No problem. Very sensitive skin? No problem. Tested it a little bit on the inside of a lip? No problem. Sprayed, spread, patted it onto the face like a toner? No problem. We were tempted to drink a little bit just to prove a point but that was clearly a terrible idea, so we didn't do that.

No one was harmed while we were doing this, human or cat or otherwise :)

Isn't hypochlorous acid really bad?

Something that will wipe out microbes (like bleach) may almost certainly be bad for us. Hypochlorous acid is one of the safer alternatives to bleach, especially for front-line workers that may be exposed to the virus constantly. It's a matter of balance: what will kill the microbes but is still safe and healthy for us? In this case, we've tested hypochlorous acids even on sensitive skin, and have had no reactions thus far. We believe that it's safer for direct application to the skin than bleach is, and can be an effective replacement for the hand sanitiser that your local supermarket might not have anymore.

What's wrong with other disinfectants?

Strictly speaking? Nothing. Each disinfectant has its own set of pros and cons, but we'll outline a few of the issues we had here:

1. Hand sanitisers often went out of stock in various supermarkets during a pandemic situation. Plus, they tend to be costly even for smaller bottles, and they might come with added peripherals that add to the cost (e.g. scents) that don't do anything to kill microbes. Plus, we can't spray hand sanitiser. I can't wipe my entire body with hand sanitiser like it's a lotion.

2. Bleach is accessible and is very strong and is used as a cleaning product. We process diluted bleach for this recipe, so why not just spray regular bleach? Answer: because I don't want to put bleach on my skin. Bleach is toxic. It is a cleaning product. The recipe called for a 1:40 ratio and the solution still smelled strongly of bleach. It is very strong. Do not put it on your skin.

3. Salt water has a long list of medical uses and cleansing and an even longer list of personal anecdotes, and it's really cheap to make! As saline, for instance, it's often used for cleaning wounds. It's great, but it's still less effective than bleach - plus, there are quite a few microbes out there that can still tolerate salt water. Otherwise, we'd all be using salt water to clean our homes instead of bleach.

some LAST notes

If you're going to use the hypochlorous acid a lot on your skin, it's probably best to moisturise often too with a lotion.

The solution smells kind of like a swimming pool, which is nice if you miss the pool this summer because of lockdown.