A type of volcanic glass, perlite is frequently used as building insulation or a potting soil additive. According to a new study, though, it also works quite well at killing malaria-causing mosquitoes.
Presently, people in malaria-prone regions regularly spray insecticides onto surfaces such as the mosquito-proof netting surrounding their beds. While this does kill many of the mozzies that land on those surfaces, the insecticides are toxic both to the people themselves and to the environment.
Seeking a more eco-friendly alternative, scientists from North Carolina State University and the Liverpool School of Tropical Medicine recently trialled a product known as Imergard WP. Manufactured by California-based company Imerys Filtration Minerals, it’s a spray made up mainly of water and powdered perlite.
The tests were conducted on four groups of huts in the West African Republic of Benin. The walls of one group were sprayed with Imergard, the walls of another were sprayed with a commonly-used insecticide (pyrethroid), and the walls of a third were sprayed with a combination of the two. The fourth group of huts served as a control, not being sprayed at all.