What Is Metaldehyde?
Metaldehyde is an organic compound, specifically a tetramer of acetaldehyde. Its CAS registration number is 108-62-3, and it is commonly known as “metaacetaldehyde” or by its IUPAC name, “2,4,6,8-tetramethyl-1,3,5,7-tetraoxocane.” Classified under various regulations as both a poisonous and deleterious substance and as a designated combustible material, metaldehyde requires careful handling.
Uses of Metaldehyde
Metaldehyde’s primary application is as an insecticide, targeting slugs, snails, and certain other gastropods. It works by inducing paralysis and causing the pests to secrete mucus excessively, leading to dehydration and death. Metaldehyde is also used in camping and outdoor activities as a component of portable solid fuels.
Properties of Metaldehyde
With a molecular formula of C8H16O4 and a molecular weight of 176.2, metaldehyde is a white solid with a distinctive menthol odor at room temperature. It has a melting point of 246.2°C, a sublimation point of 112°C, a density of 1.27 g/mL, and a flash point of 36°C. Although it is insoluble in water, it dissolves easily in organic solvents like toluene, methanol, benzene, and chloroform.
Types of Metaldehyde
Available primarily for research and development, metaldehyde is sold as a pure substance or polymer with the molecular formula (CH3CHO)n, and CAS registration number 9002-91-9. It is offered in various quantities suitable for laboratory use and may require specific storage conditions, such as refrigeration or room temperature.
Other Information on Metaldehyde
1. Synthesis of Metaldehyde
Metaldehyde can be synthesized through reactions involving acetaldehyde with calcium bromide and hydrogen bromide at 0°C or with calcium chloride and hydrochloric acid.
2. Chemical Reaction of Metaldehyde
As a colorless, needle-like crystal, metaldehyde can gradually convert to paraldehyde upon heating, decomposing to produce irritating smoke and gases starting at 80°C.
3. Basic Information on Metaldehyde With Degree of Polymerization N
As a polymer, metaldehyde is handled as a white crystalline powder with a melting point of 246.2°C and a flash point of 55°C. It is a flammable solid, soluble in hot chloroform, and mostly insoluble in water, ethanol, and acetone.
4. Toxicological Information on Metaldehyde
Metaldehyde poses risks of oral toxicity, eye irritation, and potential damage to the nervous system, liver, and testes upon long-term or repeated exposure. Ingestion can lead to a range of symptoms from mild to severe, including drooling, vomiting, diarrhea, high fever, and convulsions, necessitating cautious handling in compliance with safety regulations.