Officials in Boston have launched a new program using dry ice to suffocate rats burrowing in the city.
Researchers from Harvard and MIT were tapped by the city’s Inspectional Service Department to help devise the program, which relies on the carbon dioxide released by melting dry ice to asphyxiate the rats, USA Today reported. The method has proven to be effective and less dangerous to humans and other animals than poison.
"We’re seeing tremendous, tremendous success," William Christopher, commissioner of the city’s Inspectional Services Department, was quoted by the Boston Globe. “The simplicity of this process is one of the things that most intrigues me … and the success is what has me very excited."
Supercold dry ice is placed by workers using steel scoops into known trouble spots, the Globe stated. As it melts, carbon dioxide fills the burrow, suffocating any rats.
"It has not hurt anyone or any other wildlife or plant life. Based on everything we’ve seen so far, it’s been excellent," Christopher said to the Globe.
Complaints about rats tripled in Boston in the first quarter of 2016, USA Today stated, adding that the increase could be due to last year’s launch of a 311 system that makes it easier for residents to report rats.
Officials in Chicago and San Francisco have shown interest in adopting the new method, The Associated Press reported in a related article, adding that the dry ice technique is less expensive than conventional poison.
The new method would not eradicate rats in unconfined spaces, according to the Globe, which added that officials would still use bait, traps and poison in those settings.