Active Ingredients in Malrin Fly Bait

Active Ingredients in Malrin Fly Bait
Malrin Fly Bait is a pesticide that is scattered in outdoor areas to get rid of flies. It is most commonly used by food processing plants, kennels, warehouses, bakeries, restaurants, supermarkets and dumpsters. The bait attracts insects to the area it was applied, and kills them quickly once they consume the pesticide. The active ingredients can be dangerous to adults, and are especially dangerous to children, pets or livestock. If you are thinking about using it around your camp area, you may want to familiarize yourself with the dangers first.


Methomyl is a pesticide. According to PAN pesticide database, methomyl is used on crops such as corn, onions, lettuce and alfalfa in California. Exposure to methomyl can cause dizziness, weakness, headache, nausea, salivation, vomiting, abdominal pain and diarrhea. It can also cause problems with coordination, slurred speech, muscle twitching or blurred vision. Methomyl can cause side effects through skin absorption, inhalation, or ingestion. The PAN pesticide database lists methomyl as highly acutely toxic. It is also a suspected endocrine disruptor, which means that exposure to the chemical could affect the development of an unborn child.


According to the Environmental Protection Agency, (Z)-9-Tricosene is considered to be safe for the environment, wildlife and humans. (Z)-9-Tricosene is the pheromone of the female fly. The pheromone is used because of its ability to attract male flies to the pesticide so that they are killed before they can mate. The EPA also notes that (Z)-9-Tricosene is harmful to bird reproduction and some aquatic invertebrates. However, the EPA asserts that it is unlikely to enter water bodies, and they only approve uses where bird exposure in unlikely, as well. PAN Pesticides Database lists the chemical as slightly toxic.


Muscamone is a chemical that is trademarked by Wellmark International, which is the company that manufactures Malrin Fly Bait. Muscamone attracts both male and female flies to the bait. The chemical is the manufactured form of (Z)-9-Tricosene. Originally, the (Z)-9-Tricosene pheromone was isolated in the female fly, and then it was manufactured and trademarked as Muscamone. Often, Marlin Fly Bait carries a front label that states, "With Muscamone".

Article Written By Robin Coe

Based in Ann Arbor, Mich., Robin Coe has reported on a variety of subjects for more than 15 years. Coe has worked on environmental health and safety issues in communities across Ohio and Michigan. Coe holds a Bachelor of Science in journalism with a double-major in international politics from Bowling Green State University. She has also received training and experience as a nurse aide.

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