By Steven Voser

Bongs are a staple piece of equipment among cannabis lovers, and it’s not hard to see why. The water inside, and the design that allows for it, helps to make hits smooth by cooling down the smoke and filtering out tar and ash that would otherwise get in your airways.

Once in a while, though, you’ll need to get up and replace the water in your bong. Why is that? Doesn’t the water keep doing its job regardless? Well, as we’ll explain in detail later, regular replacement is key if you want to get the most out of your bong water.

What's the Point of Bong Water

Bongs come in all shapes and sizes, but regardless of what they look like (or how much they cost you), all bongs have one thing in common. That, of course, is the fact that they have at least one large chamber dedicated to water.

And, besides creating that reassuring bubbling sound that lets you know your bong’s working, the water that you use to fill the chamber(s) of your bong plays two very important roles.

First and foremost, the water in your bong works as a filter. When we combust cannabis, we actually change the chemical composition of the plant, turning THCA (a non-intoxicating acid) into THC, the cannabinoid that gets us high. However, the act of combustion also creates hundreds of secondary toxic and carcinogenic compounds that are often grouped together and simply called “tar”.

For example, studies[1] show that cannabis smoke is qualitatively very similar to tobacco smoke, both being particularly rich in polycyclic aromatic hydrocarbons (naturally present in coal, crude oil, and gasoline), which are infamous for their carcinogenic and mutagenic properties.

Bong water helps to trap at least some of these compounds from the smoke, as well as filter out any ash or plant material before it reaches your mouth and airways. Is it a perfect filter? No—but it does the job well enough to make it cleaner than other smoking methods in the long run.

Second, the water in your bong also cools the smoke before it hits your mouth, making for a smoother hit that’s less irritating on the lungs.

How Does Bong Water Filter Smoke?

So, considering it just sits at the bottom of your piece, how exactly does bong water filter smoke? To figure this out, studies have explored the difference in chemical composition between regular tobacco smoke and tobacco smoked from a water pipe, and the results are very promising.

Studies[2] dating back to the 1960s, for example, show that the water in a water pipe works as a very effective filter, trapping up to 90% of phenols (which are cardiovascular toxins, act as tumour co-promoters, and show genotoxic activity), as well as up to 50% of particulate matter and benzo(a)pyrene (a highly carcinogenic polycyclic aromatic hydrocarbon).

Other studies have also compared the carcinogenic properties[3] of bong water to that of water-filtered smoke. The results from this research found that the water left in a bong was far richer in carcinogens than the smoke that it filtered.

More recently, researchers from the University of Texas and the Harvard School of Public Health conducted cellular toxicity tests[4] on both cannabis and tobacco smoke.

They found that filtering both types of smoke through water helped remove acrolein and acetaldehyde, two toxins that attack alveolar macrophages, one of the main defense cells of the lung. When exposed to unfiltered tobacco or cannabis smoke, the ability of these cells to kill bacteria was strongly impaired.

How Does Bong Water Filter Smoke?

Does Bong Water Filter Out THC?

So, there’s solid research to show how bong water filters out toxins from cannabis smoke. But, the fact that water makes for such an efficient filter also raises one very important question; can the water from your bong also filter out cannabinoids (like THC and CBD) and terpenes?

The short answer is yes. Just how many cannabinoids or terpenes your bong water filters, however, is negligible compared to its ability to filter toxins and irritating particles (like ash and plant matter). That’s because most of the active cannabinoids, terpenes, and flavonoids in cannabis smoke aren’t water-soluble (which is also why, for example, dunking cannabis buds in tea won’t get you high).

Studies have shown, however, that between 20–40% of the THC in cannabis smoke can bind to the glass[5] in your bong, with even more getting lost if your bong is plastic. To fix that problem, however, just store around for glassware that has been silyl-treated and doesn’t contain any rubber or plastic components.

What is arguably more concerning than THC trapped in your bong water, though, is how compounds in your water might alter the smoke passing through it. If you use highly chlorinated tap water in your bong, for example, the chlorine will carry into the smoke.

Will Drinking Bong Water Get You High?

So, since THC gets absorbed into it, could you get high by drinking bong water?

No. Please don’t let your friend (or whoever else gave you this brilliant idea) trick you into drinking bong water.

Cannabinoids, as we mentioned earlier, aren’t water-soluble. If you want to get high from eating or drinking cannabis, you need to heat and mix it with some kind of fat. If you really want to drink your own cannabis, consider mixing some cannabutter or oil with honey and use it to sweeten your warm drink of choice, or use cannabis-infused chocolate to make yourself a hot chocolate!

The Benefits of Changing Bong Water Regularly

So, to break things down clearly, these are the main benefits of changing your bong water on a regular basis:

  • Better flavor: Tar, resin, and ash trapped in your bong or bong water have a massive impact on the flavor of your weed. If you want to preserve the flavors of your kush, make sure you clean your bong water regularly and fill it with natural spring water.
  • Better filtration: Clean water is more effective at filtering toxins and irritating compounds (like ash and leftover plant matter) from smoke. Make sure to change your bong water regularly to enjoy the best filtration from your bong.
  • Longer-lasting glassware: Bongs and glass pipes simply last longer when they’re properly cared for. Cleaning your bong regularly per the instructions below will help keep your glassware free of stains and imperfections for as long as possible.
The Benefits of Changing Bong Water Regularly

How Often Should You Change Your Bong Water?

How often you change your bong water or clean your bong comes down to personal preference. But, ultimately, the more often you do so, the better.

At RQS, we’re keen on preserving the flavor of our weed and having the best smoking experience possible. Hence, we recommend you clean your bong before each use, and make a point to change your bong water for each session.

How To Tell if Your Bong Water Needs Changing

Here are a few tips to help you spot when your bong might be in need of a clean or fresh water:

Foul Odour
If your bong reeks, that’s a telltale sign it’s in need of a clean and a change of water. If your bong smells off, make sure to give it a deep clean with detergent or saltwater and sterilise it with alcohol.
Brown Water
Brown bong water is another sign that it’s time to clean your piece. The resin and tar present in cannabis smoke will, over time, stain the water in your bong, as well as the glass. Regularly cleaning your bong can help your glassware look its best for longer.
Resin Buildup
No matter what people tell you, don’t get tricked into scraping resin off your bong and packing it into a bowl. If you notice brown or black resin building up around any part of your bong, it’s time to give it a clean.
This is pretty obvious, but if your bong has trapped mold, give it a solid clean and sterilise it before your next session. Stagnant water provides a breeding ground for fungi and bad bacteria that should be nowhere near your mouth or lungs.

Can Bong Water Make You Sick?

If it gets dirty enough, can bong water make you sick? As it turns out, yes. As we saw earlier, the water in your bong serves as a filter that traps toxins, ash, and tar. Drinking it would be like eating the filter tip of a cigarette, and would likely make you very, very sick.

Is Bong Water Good for Plants?

You still may not want to waste the water, however, and may be wondering whether you could give it to your plants. Again, it helps to think of the water in your bong like the filter tip of a cigarette; just like cigarette butts have no place in your garden, nor does bong water. Unfortunately, there is no real practical use for bong water other than flushing it down the drain.

How To Keep Your Bong Clean

Cleaning and preparing your bong isn’t rocket science. For best results, simply dismantle your bong and soak all of its components in warm, soapy water for about 15 minutes. Next, use a soft brush to scrub the glassware and bowl. Finally, rinse all parts of your bong under warm water to remove any of the soap, and let them dry separately before you reassemble your piece. Fill it with water before your next session, and voilà!

External Resources:
  1. Polycyclic Aromatic Hydrocarbons in the Mainstream Smoke of Popular U.S. Cigarettes
  2. Comparison of the yields of several selected components in the smoke from different tobacco products
  3. UKCIA Research Library
  4. Marijuana and tobacco smoke gas-phase cytotoxins - ScienceDirect
This content is for educational purposes only. The information provided is derived from research gathered from external sources.

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