How long does rat poison last? [Safe Storage Tips]

One of the most heated topics in rat poison forums is how long rat poison lasts. Rats are stubborn creatures that not only spoil our food but as well as carry diseases that are dangerous to humans. Luckily, various traps and poisons can be used to kill rats.

Unluckily, some people have rat infestation that doesn’t disappear completely. If you’re having a rat infestation and are wondering whether to use the rat poison that you used almost a year ago, you’re in the right place.

Summary of Contents

How long does rat poison really last?

Rat poison can last for an extended period if kept well. However, the poison will not be as effective as it could’ve been before expiring. The moment you open a pail of rodenticide, the bait can remain effective for at least one year. However, if it’s a block of mouse poison in a bait station, it should be thrown away in 30 days.

Since rodenticide is made from organic materials with a shelf life, it will expire and degrade after some time. Rodenticide, or rat poison as it’s popularly known, is made up of chemicals that are used to control the rat population. Most rodenticides usually are in the form of food bait and are not the kind of poison that can kill instantly.

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However, the chemicals in these baits have been created to kill rats a few days after ingesting to avoid becoming suspicious of the bait. But as expected, rat poison does not last forever, meaning it has an expiration date.

Irrespective, it would be best if you never were careless, even with an expired rodenticide. This is because the rodenticide may expire, but the poison inside it may still be useful. Therefore, you should never use your bare hands to clean up expired mouse poison bait. In case you have direct contact with it, you should wash your hands thoroughly with soap and running water. This is important because the chemical inside needs a small dose to be lethal even to humans.

Despite rat poison expiring, the organic toxins will degrade over time, but the chemical poisons will remain potent for many years to come. The only thing that will take place is that they will have a reduced concentration of their active ingredient. It’s also crucial to note that the rate of degradation will depend on particular compounds in the rat poison. You may note that some rodenticides will lose half of their concentration in a few years, while others may take longer.

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Is it okay to reuse expired rodenticides?

As stated above, most rat poisons go for at least a year when opened before going bad. After this period, the poison may become less effective and less appealing to rats. It’s vital to understand that the expiration date written on rodenticide is usually for the packaging and the materials used and not for the poison’s chemicals.

Nevertheless, even if the poison has expired, it can still be used, but it won’t be as effective as before. But with rats, you don’t have to worry as both excellent and spoiled food is still appealing to them. Some rats will even go to the extent of trying out the bait and having a taste of the expired bait. Of course, they will die, but don’t expect the numbers to be up.

Expired rat poison can kill half the number of rats that fresh rat poison can kill. For instance, if the mouse poison killed 20 rats last year, expect it to kill between 8 and 10 rats. This is exceptional considering the rat poison is expired.

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Is expired rat poison more dangerous?

This depends on the chemical make-up of the rat poison and how it’s kept. Poison may lose or gain potency after some time. However, since most mouse poisons come with chemicals, such as zinc phosphide and warfarin, these chemicals start to degrade faster after they are opened. Nonetheless, it would help if you did not let this fool you as they are still lethal to the rat and yourself.

For this reason, you should always be adequately rid of expired rat poison. On top of that, it should be out of reach for kids and pets. However, even though you can still use expired rat poison, keeping this rodenticide in your home is very risky if it gets into the wrong hands. That’s why you should discard it if you no longer need it.

What is the best way to keep Mouse poison?

After you open a poison pail, you should expect it to expire after around one year. The excellent news is that you can extend the lifespan of the rat poison by storing it properly. To slow down its expiration, you will have to keep your baits in an airtight sealed container. This will ensure that nothing speeds up the breakdown of the ingredients in the poison.

To avoid the wrong people accessing the container, you should lock it up in the cabinet. Besides, you should ensure that kids and pets cannot reach it. With such storage, expect your poisoned baits to last a little bit longer.

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Some areas have a widespread rat infestation, making complete elimination quite challenging. As a result, having rat poison throughout is very crucial to control their population. If you live in such an area, you can keep poison baits for over a year as long as you keep them properly.

Rat poison can last for a year or more if properly kept. However, baits in a bait station can last for 30 days after being left open. So, if you intend to reuse rodenticide, you should keep it in an airtight sealed container. However, it’s vital to know that expired rat poison will not be as effective as fresh mouse poison, but it will still kill these pesky creatures.

If you intend to keep rat poison for long, make sure it’s out of reach of kids and pets.

1 thought on “How long does rat poison last? [Safe Storage Tips]”

  1. My ex/ soninlaw randomly spread rat poison in a shed we would like to cleannout. It has been at least 4 years. How can we safely clean it out!

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