Pesticides used to control rodents are known as rodenticides. In instances when the presence of mice in a certain area is already causing both economic and health damages, the use of rodenticides can be considered as to most practical way to get rid of the mice. Products that are intended to poison and kill mice are already widely marketed nowadays. These products are classified according to their toxicity levels. Moreover, rodenticides do not poison pest mice alone. Rodenticides can also poison humans through repeated ingestion or through direct injection. The effects of rodenticides to both vermin and humans are almost very similar. In both cases, the poison targets the internal organs. Smaller animals receive the most damage from rodenticide ingestion primarily because of their size. This is also the reason why rodenticides cannot harm humans as fast as it can harm rodents.
There are three levels of rodenticides toxicity: High, Moderate and Low
High Toxicity
There are six types of compounds which are legal to us of high-level rodenticide, these are: Arsenic, Sodium Monoflouroacetate, Strychine, Thallium, Yellow phosphorus and Zinc Phosphide. Rodenticides having these types of compounds that are formulated to have a dosage that reaches up to 50 milligram per kilogram of the body weight of the target pest are regarded as very strong rodenticides and are usually not advisable for use because of its very lethal effects to the human body in case of accidental or incidental ingestion.
1. Arsenic
Arsenic can cause death through damaging the circulatory system of the body. It usually causes severe muscle cramps, vomiting and convulsions. High dosage of arsenic can cause bloody diarrhea and dysphasia, both of which are the early symptoms of a damaged circulatory system. Arsenic comes in the form of a white crystalline powder, close to the appearance of a very refined table sugar.
2. Sodium Monoflouroacetate
This compound is extremely toxic when ingested or absorbed by the body through open wounds and cuts. Sometimes, sodium monofluoroacetate gets mixed with dust and is accidentally inhaled by unsuspecting targets. The possible effects of sodium monoflouroacetate to humans have been studied by experts by testing it on primates. The researchers concluded that the compound can cause cardiac arrhythmias to humans, a heart condition which can possibly lead to comatose. Humans are also expected to experience seizures and respiratory failures after ingestion. Other possible effects to humans are bronchopneumonia and ventricular tachycardia. To pests like mice, a little amount of sodium monoflouroacetate can already lead to an instant death. Sodium monoflouroacetate looks like flour. It is white, tasteless and does not produce any odor. Sodium monoflouroacetate is simply a water-soluble salt compound.
3. Strychnine
This compound is used to stimulate the central nervous system of anyone (pest or human) who has ingested it. Through stimulation, Strychnine is able to cause recurrent motor seizures that are usually very painful. Pest usually end up dead after taking in this compound, on the other hand, humans will experience blurred vision and nausea. Eventually, a person who has ingested this compound will feel severe muscle spasms and diaphoresis.
4. Thallium
Thallium is probably the most dangerous high-toxic rodenticide compound known to mankind. No antidote for thallium has ever been developed ever since and experts are still in a constant search for solution to thallium ingestion. So far, thallium has already been strictly banned in all countries worldwide because of this harm. In small dosages, thallium can cause complete hair loss, bronchopneumonia, severe abdominal pains, parenthesias and pulmonary oedema. The effects of thallium are long-lasting that pests that died due to it can still carry the compound in their carcass. Other pests coming across these carcasses can also die because of second hand exposure to thallium. This compound is tasteless and odorless too just like sodium monoflouraoacetate, but unlike other compounds, thallium can penetrate through unbroken skins, making it very dangerous to humans.
5. Yellow Phosphorus
This compound is usually mixed with sticky food bait when used as a rodenticide. Its effects to the body are usually seen in the gastrointestinal tract and liver because these are the parts of the body where phosphorus is mostly stored. After ingestion, the rodent will experience vomiting. The vomit is usually glistening and smells like garlic, after which, the pest (or the human or pet) will be in a coma or die because of heart failure.
6. Zinc Phosphide
By nature, zinc phosphide is not a very dangerous compound, but when mixed with water, it releases a deadly gas called phosphine which is highly toxic. Poisoned rodents and people poisoned by accident usually experience vomiting, renal damage and circulatory collapse. Other effects of the phosphine gas released by zinc phosphide are convulsion and comatose. In other instances, it can also lead to leukopenia and death in as short as a week or two. In general, zinc phosphide is not attractive to pests because of its appearance and its "rotten fish" odor. This is the reason why it is usually mixed with food baits.
Moderate Toxicity
There are so many different compounds which can be used to develop moderately toxic rodenticides. In fact, any pesticide with alpha naphthyl thiourea (ANTU) ingredients that are formulated in a 500 milligram per kilogram of target's body weight can be classified as a moderately toxic rodenticide already. DDT is also very common is such kinds of rodenticides. The effects of ANTU to the body are not as harmful as those that are caused by high toxic rodenticides but these health effects still merit sufficient caution. While pests would definitely die after a few intakes of such kind of rodenticides, humans will experience hypothermia and pulmonary problems when exposed to these rodenticides. In many cases, those with suicidal tendencies can deliberately use this rodenticide and still achieve his or her desired result with a couple of doses.
Low Toxicity
Rodenticides with low toxicity levels are often advised for general usage. In fact, all of the rodenticides readily available to homeowners are of low toxicity. There are three kinds of low toxic rodenticides: Anticoagulant, Norbomide and Red Squill. Low toxic rodenticides are usually formulated to contain LD50 that amounts to 500 or 5000 milligram per kilogram of its target's body weight.
1. Anticoagulant
By restricting the production of white blood cells, anticoagulant rodenticides can cause severe damage to the pest mouse by making its body unable to clot whenever it is wounded. Internal bleeding is very possible and the in a couple of days, the mouse will suffer from de-coagulation and then die.
2. Norbomide
This compound is found to be the safest to use at home because it does not have any bad effects to humans. It is simply a smooth muscle constrictor, and since mice and rats have norbomide receptors embedded in its smooth muscles, they are directly affected by the compound. Its effect in a rodent's body is strong enough to lead to ishaemic necrosis and death.
3. Red Squill
This compound has very strong emetic properties causing excessive vomiting in pest mice. They would have difficulty in absorbing nutrients through their intestines and thus they end up starving or malnourished. In some cases, mice die because of severe damage to their internal organs caused by the vomiting.
If you are worried about using these toxic substances in places where your pets live, read this "Rodenticide Poisoning in Pets" right now!
All the best,
Sergiu Zburatoru