When you see a mouse skittering around the floor of your kitchen tiles at midnight, your heart will definitely drop because there’s no way it could be an isolated incident. Sadly, it’s never just one. Spotting a single mouse is usually the “tip of the iceberg” moment and a signal that your home’s defenses have been breached, and you’ve likely got some uninvited roommates moving into your walls, chewing on your wires, and eyeing your pantry.
For generations, families and DIY enthusiasts have passed down a bit of “homestead wisdom” known as the “rice trick.”
Yes, I’m aware that this trick sounds too good to be true, but trust me, all you need is some rice along with a couple of household ingredients to get rid of the mice wandering around your home. So, despite seeming like something that your grandfather could have sworn was true, there is some very interesting science behind this process.
Given the concerns about the harmful substances present in many industrial rat poisons, the effectiveness of this technique in ensuring that your house is rodent-free without turning it into an unhealthy place for your pets and children has made it extremely popular. In this essay, we will learn more about the mechanics behind this effective and healthy alternative to poisons, its unique way of acting on a mouse’s physiology, and the tactics that work well here.
The Science of the Bait: Why Rice?
Rodents, specifically Mus musculus (the common house mouse), are characterized by high metabolic activity. Thus, they need to consume 10-15 percent of their body weight per day to survive. As foragers, rodents have a predisposition towards carbohydrate-rich food sources.
There are two reasons why rice is an ideal “carrier” for the bait.
Firstly, mice are very fond of rice; therefore, it makes it easier for the animals to either chew the substance on-site or transport it back to the nesting place to be shared with other members of the colony.
Secondly, dry rice acts as a substrate which helps to absorb any powdered materials such as baking soda or plaster.
The Chemical Mechanism: Baking Soda and Rodent Physiology
The most widely used form of this remedy uses a mixture of half dry rice and baking soda (sodium bicarbonate). In order to understand how this works, it is important to know about the biological peculiarities of a mouse’s body.
The “No-Burp” Biological Defect
Unlike humans, mice and rats have an anatomical limitation that prevents them from regurgitating anything they ingest. They lack an effective gag reflex and cannot vomit. In addition, a mouse’s stomach is divided in a way that restricts the movement of air or solid contents back into the esophagus.
When the mouse eats baking soda, it begins to interact with the hydrochloric acid (HCl) in the mouse’s stomach. This chemical reaction is identical to the one you see in a school science volcano.
In a human, the resulting carbon dioxide is simply expelled, while in mice, it accumulates in the digestive tract. Due to the inability to release the gas, the pressure mounts to the point where the insides are damaged or fatally blocked. It is a fast process but occurs out of sight of the baits as it takes some time for maximum pressure to be attained.