Glendale is set to swap a poison that parks maintenance workers use to kill mice and rats for one that’s less dangerous to other wildlife that may eat the rodents, following City Council review this week.

Councilwoman Laura Friedman’s concerns about the detrimental effect of the previous rodenticide, which prevents blood from clotting causing the animals to bleed to death, prompted the shift.

“The target of these poisons is not to kill the mountain lions and the owls and all of these other predators out there, it’s just to target the rats that can spread in the parks,” Friedman said at a Tuesday council meeting, adding that rat poisons faced greater scrutiny after a mountain lion in Griffith Park was sickened by the product.

The mountain lion, known as P-22, contracted mange, a skin disease, after being exposed to rodenticides, according to the National Park Service website. Two other mountain lions have died because of the rat poisoning. P-22 shot to stardom after National Geographic magazine featured a picture of him in front of the Hollywood sign last year.

Rodenticide’s secondary impact on other wildlife has been a controversial issue for years nationwide, with environmental activist groups acting as the loudest critics.

Glendale parks staff kill rodents in parks for public health reasons because they can spread diseases to humans, according to the city report, but poisons can still be an issue in parks near open spaces, where other wildlife live.

The new toxin, Fastrac, is a safer alternative because it does not kill the wildlife that eat poisoned rats or mice like the previously-used poison called Contrac Super Size Blox did, according to a city report.

Contrac causes rodents to bleed to death, said Community Services & Parks Director Jess Duran, but Fastrac attacks the rodent’s nervous system, instead. Rodents also need to eat less of it to die, which means if an animal up the food chain eats the rodent, it, too, consumes less poison.

Glendale stopped using the rodenticide that makes rats bleed to death in September. Crews have not been using any poison since then.

The new poison is more expensive, but the cost is nominal compared to big-ticket city expenses.

Fastrac costs almost four times more than the old poison. Over the past three years, the average amount of poison used was 75 pounds at a cost of about $386, according to a city report. By switching to the new poison, the city is expected to spend $1,433, a difference of $1,047, over that same time period.

The highest rat and mice populations are at Deukmejian Wilderness Park, Montrose Park, Verdugo Park and the Glendale Sports Complex.

Friedman said she hopes Glendale’s poison change prompts other cities to make the switch, too.