The castor oil plant, which is used to make laxatives, now possibly holds the key to controlling the mosquito menace in a ‘green’ way.
A study conducted by the department of zoonosis at Haffkine Institute for Training, Research and Testing, Parel, has revealed that castor oil can be used to kill mosquito larvae.
“Among the various herbal plants that we tested, the oil extract from the seed of the castor plant showed the best results for larvicidal [killing larvae] activity as well as inhibiting growth of Aedes aegypti mosquito larvae,” said Dr Saroj Bapna, scientific officer of the department.
In laboratory tests, the castor seed oil extract was able to kill 50% of the larvae in 24 hours.
The institute plans to publish the study, which was conducted between January and March, in its journal, Haffkine Bulletin.
The best way to keep mosquitoes in check is to use effective larvicides at the larval stage, said Bapna.
“A variety of synthetic insecticides are used in chemicals used to control mosquito larvae. Although these insecticides are effective, they pose serious health and environmental hazards. Besides they develop insecticide resistance and undesirable effect on non-target organisms,” said Dr Abhay Chowdhary, director of the institute.
“We need to look at the short-term and long-term toxicity of the seed oil extract. If we get some good leads, we will definitely apply for a patent,” said Chowdhary.