When loved ones go missing time is of the essence.
"The most important part of our searches is the start," said Officer Jim Pacetti, Cook County Sheriff's Office. "And to have a perfect start, we have to have an ideal scent article of the person we're looking for."
More than half a million people go missing in the United States each year. Often, bloodhounds are brought in to help with the search. But the first challenge law enforcement faces is providing the dogs with a clean scent item to follow, one that hasn't been contaminated by other people living in the same household.
Sheriff's departments around the country are now promoting the use of scent kits, particularly for those at higher risk of getting lost, such as people with autism, dementia and Alzheimer's.
"About half of this community wanders or they're prone to movement," said Colleen Shin of Autism Speaks. "They're going from a safe to an unsafe environment. They're drawn to water a lot of times. So having a proactive measure like this is just a wonderful thing to do."
"There's a swab inside the kit. What you do is you use it. You rub it on your body. You take it, you put it in a jar, you put it in the freezer and for 10 years that is good," said Cook County Sheriff Tom Dart.
The Cook County Sheriff's Office has purchased 800 of the scent kits to start, and will hand them out for free to anyone who puts in a request for one.