Is Lysol Septic Safe? | Septic System Tank Maintenance Tips

Is Lysol Safe for your Septic System?

Since we started this blog and wrote about living in a home with a septic system, many of our readers have asked about specific brands of cleaning products, wondering if common household brand names like Comet is safe for their septic system or general recommendations on good septic-safe toilet bowl cleaners and laundry detergents.

Another common question is if Lysol is septic-safe so we’re written this short summary of what we’ve found out.

First of all, Lysol makes a wide range of products. While many people may be thinking of the Lysol® Disinfectant Spray that comes in an aerosol, Lysol also makes anti-bacterial wipes, toilet bowl cleaners (both automatic flush tablets and liquid bowl cleaner) as well as laundry sanitizer and hand soap. So there really isn’t just one Lysol product.

However most of products in the Lysol product line do have ingredients in common, most notably MIPA-BORATE (Boric Acid) which has been shown in studies to have negative effects on developmental/endocrine/reproductive systems and AMMONIUM HYDROXIDE which is found to be highly toxic to aquatic life and can cause skin irritation and damage to eyes in humans.

The Environmental Working Group gives LYSOL Disinfectant Spray as grade of D.

Some Lysol products are actually categorized as pesticides by the Environmental Protection Agency (EPA) (opens PDF).

As we explain below in more detail, septic tanks need a healthy population of bacteria in the tank for it to work efficiently and harsh chemicals are the most common cause of disrupting the delicate balance.

So that brings up the common question: is Lysol one of the harmful chemicals that is detrimental to your septic or is it safe enough to use? 

Seventh Generation Free & Clear All-Purpose Cleaner, 32 oz
Seventh Generation (Image: Amazon.com)

We don’t use Lysol products in our home. We prefer using a cleaner like this Seventh Generation Free & Clear All-Purpose Cleaner

While some people would argue that when used in moderation, the chemical ingredients in Lysol are not enough to kill off the bacteria in a large septic tank. And we understand that realistically the way disinfectant sprays are used (mostly sprayed on surfaces and wiped), a very small amount will probably end up directly in your septic system.

However, even small amounts of bleach and harsh chemicals like drain cleaner have been shown to kill off bacteria in septic tanks.

More importantly for us is that apart from maintaining a properly functioning septic tank, we try to keep a toxic free home as much as possible and see no need to use the kind of chemicals that are contained in Lysol Disinfectant,

Lysol Multi-Purpose Cleaner w/ Hydrogen Peroxide - Citrus Sparkle Zest - 22 oz - 2 pk
Lysol with Hydrogen Peroxide (Image Source: Amazon)

especially since there are other products on the market that do a very good job of keeping our house clean and smelling fresh without the use of such harsh chemicals. 

If you are used to using Lysol and like the product you may want to consider changing over to their LYSOL Power & Free Multi-Purpose Cleaner, which is a less toxic version and scores much better on health and safety ratings.

If you are living with a septic system, you may want to check out our recommendations for septic safe laundry detergents

Understanding your septic system and the importance of healthy bacteria:

example of septic system
Source: cleanseptictank.org

The important thing to know is that a septic system works by allowing the natural bacteria to break down the waste in the tank. The word “septic” in medical terms actually refers to being infected with bacterium. A healthy septic system only works efficiently when bacteria are allowed to thrive in the tank.

The bacteria feed on the solid human waste and other solids in the tank (toilet paper and cooking oil, small food particles that make it into the tank through the kitchen drain).

The liquid is then drained thru the leaching field where it goes through a final purification normally passing through multiple layers of filtering normally sand and peat before finally being allowed back into the ground.

When working properly almost all of the solid waste will be consumed with only a small sludge layer left at the bottom that will need to be pumped out.

The number one enemy to a properly functioning septic tank is the harsh, toxic chemicals found in many household cleaners. Bleach and other cleaners are powerful enough (even in relatively small amounts) of killing the healthy bacteria that keep your septic tank working.  If you put too many chemicals down the drain it could be enough to kill off the bacteria, turning your tank into a stagnant pool of waste that is not being broken down.

The end result will be a full tank of waste that needs to be pumped by a septic maintenance company = money. In our area, this costs around $300-$400 but may cost more in your area- especially if your tank is not easily accessible or you have a tank lid that is buried and needs to be excavated.

This all brings up another question…do you really need to buy septic tank treatments, enzymes or activators?

You may also be wondering if you can use a garbage disposal with a septic system – find out here.


Featured image: Barbara Wells on Flickr