Methomyl is a broad spectrum insecticide that was first introduced in 1966. These days, this chemical is used for killing spiders. Furthermore, it is commonly used during the foliar treatment of field crops, fruit and vegetable crops, commercial ornamentals, cotton and above all in diaries and poultry farms. There are two main advantages of using methomyl. Firstly, it is used as contact insecticides as it kills target insects and secondly, it is used as a ‘systematic insecticide’. This is because once methomyl is transported and absorbed it can cause an overall ‘systematic’ poisoning in the targeted insects. The best part about this chemical is that it does not do any harm to the plants even if when they absorb the insecticide. This chemical falls in the group of ‘carbamates’.
Methomyl and Its Acute Toxicity
Methomyl is a very toxic material for humans. It can get really dangerous when it is absorbed through eyes and can be lower toxic if inhaled. The most common symptoms of anti-cholinesterase include blurred vision, weakness, nausea, headache, chest discomfort, abdominal cramps, sweating, constriction of pupils, decrease pulse and muscle tremors. In case of severe poisoning, there is giddiness, twitching, muscle incoordination, confusion, low blood pressure, slurred speech and heart irregularities. There have been many cases which turned to fatal because of paralysis of muscles of the respiratory system, discontinued breathing and severe constriction of the opening of lungs. When a person is severely affected by methomyl he can be recovered only when exposure ceases. This will give the victim sufficient time to attain normal level cholinesterase.
Chronic Toxicity with Methomyl
When an individual gets a repeated or prolong exposure to methomyl he may have the same adverse effects as listed above. Even if there is a repeated exposure of methomyl in small amount the victim can experience symptoms of muscle aches, lack of appetite and weakness. The problem of cholinesterase-inhibition can last for six weeks as well and is only reversible when the exposure is discontinued.
Ecological Effects of Methomyl
The tests have shown that methomyl is quite harmful for birds, fish and other wildlife. Birds are believed to be highly affected with this chemical. When the test was carried out on birds, clinical signs of salivation, tearing of the eyes, respiratory and occasional convulsions were quite evident. On the other hand, when the same test was carried out on fish, they were moderately affected as compared to the birds. However, it depends on the type of fish which was tested. When the effects of methomyl on other aquatic organs are discussed, bees are adversely affected.
Methomyl is highly soluble in water and has a soil-half life as well. This indicates that it has a potential for groundwater contamination. Overall, it tends to have a low persistence in the environment. Special take has to be taken when dealing with methomyl products. Specialists advise to wear protective clothing and eyewear and one should mix them from a distance. It must be kept in dry places where there is contact with water.