Four out of 45 insect repellent products available in Hong Kong contain excessive DEET, which is unhealthy for children, Ming Pao Daily reported Tuesday, citing the Hong Kong Consumer Council.
The concentration of DEET (diethylmethylbenzamide) in the four products, which can be used by adults as well as children, ranged between 19 percent and 34.34 percent, far exceeding the 10 percent ceiling recommended by the Health Department for repellents used by children, it said.
Overuse of DEET could lead to spasms and neural paralysis, the council said.
It called for the government to tighten regulations.
Effectiveness in repelling mosquitoes varies among different ingredients, the council said.
It said the concentration of an ingredient affects not its effectiveness but the duration of protection.
For instance, DEET remains effective for one to two hours at a concentration of less than 10 percent, while the effect can last for as long as six hours when its concentration rises to between 30 percent and 35 percent.
However, the effectiveness of mosquito repellents can also be influenced by the rubbing of the skin, sweating and the user’s environment.
3M insect repellent, which says on the label that it is for children’s use, was one of the four brands with excessive DEET.
The company said such products have been sold in Hong Kong for 10 years, and no complaints of harm have been received.
It said repellents containing DEET are safe and effective as long as they are used appropriately, citing the US Centers for Disease Control and Prevention.
The DEET concentration of Johnson’s Off repellent lotion was found to be 25 percent, also exceeding the standard.
The Health Department recommends that babies under six months do not use repellents containing DEET.
– Contact us at [email protected]