Metaldehyde

Metaldehyde is a chemical that is commonly used as a pesticide against slugs, snails and other gastropods. Metaldehyde is a cyclic oligomer of acetaldehyde, with IUPAC name: r-2, c-4, c-6, c-8-tetramethyl-1,3,5,7-tetroxocane.

As a pesticide
It is sold under various trade names as a molluscicide, including Antimilice, Ariotox, Cekumeta, Deadline, Halizan, Limatox, Limeol, Meta, Metason, Mifaslug, Namekil, Slug Death, Slug Fest Colloidel 25, Slugit and  Slug-Tox. Typically it is applied in the form of slug pellets, which might include a protein bait, as well as dust foams.

Other uses
Metaldehyde is also used as a camping fuel. It may be purchased in a tablet form to be used in small stoves. It is sold under the trade name of "META" by Lonza Group of Switzerland.

Metaldehyde has been used in cloud seeding experiments, such as a project called “Experimental Seeding Tests," sponsored by the National Science Foundation at the University of Utah. The experiment was conducted during 1981-1982 and its stated purpose was to compare metaldehyde and silver iodide through airborne seeding tests in supercooled stratus clouds.

Safety
Metaldehyde is classed as a ‘moderately hazardous’ pesticide by the World Health Organization and is toxic to all animals that ingest it. Metaldehyde is highly toxic by inhalation, moderately toxic by ingestion and slightly toxic by dermal absorption. There is widespread concern that there have been an unacceptable number of poisoning incidents, especially involving domestic pets, wild animals and birds. Metaldehyde is also known to be carcinogenic in large quantities or through prolonged exposure.