Detecting Deadly Chemicals

Source: http://www.sciencedaily.com/videos/2006-12-10/

Computer Scientists Develop Portable Evidence-Gathering Tool

Science Daily — Investigators on a crime scene can now use a new tool for collecting chemical or biological samples. The sampler gun collects samples on a cotton pad -- eliminating direct contact with anything harmful, as well as risk of contaminating evidence -- a GPS system to record the samples' location, a camera that snaps pictures for evidence, and a digital voice recorder and writing pad for taking notes.
LOS ALAMOS, N.M. -- Whether it's a murder, a break-in, or an anthrax scare, investigators trying to solve a crime are burdened with collecting delicate, sometimes toxic evidence.

Mention white powder and mail, and who can forget the deadly anthrax scare that swept America? Jennifer Greenamoyer remembers it well. "This is the building where they sort the mail, and this building was contaminated and was the first building to be closed," she says.

Greenamoyer was a congressional staffer during anthrax scare. "Even though I didn't necessarily feel like I was exposed or I was kind-of at risk -- you knew that other people in the building had been."

She was safe, but there's still danger to investigators going back inside to collect samples for analysis. A new device, called the Hands-Off Sampler Gun, eliminates the risk of collecting toxic materials.

"You don't get exposed yourself to the potential agent, anthrax, and you're also not contaminating the sample media," computer scientist Torsten Staab, of the Los Alamos National Laboratory in New Mexico, tells DBIS.

Traditional ways of gathering harmful chemicals use many gadgets. This device puts several technologies into one, easy-to-use gun.

Developed by computer scientists, the Hands-Off Sampler Gun has a cotton pad that grabs chemicals to eliminate direct contact with anything harmful. A GPS system tracks the location of a chemical and the investigator. It also includes a camera that snaps pictures for evidence and a voice recorder and writing pad to take digital notes. The all-in-one device is important to identify a chemical and its risk factor and make sure everything is safe for everyone.

The Sampler Gun could also be made useful for collecting evidence, like bloodstains at crimes scenes. "We have all the information at the end, electronically. It could be wirelessly transmitted from the field to the laboratory," Staab says.

The FBI plans on field testing the device with its Hazardous Response Unit early next year.

BACKGROUND: Researchers at Los Alamos National Laboratory are developing a Hands-Off Sampler Gun that would automate the otherwise expensive and time-consuming process of maintaining a proper chain of custody for forensic evidence collected at crime scenes. This will help keep evidence from being mishandled and ensure more credible evidence for jurors. The gun is being marketed initially for forensic biology applications, but could also prove valuable to counter-terrorism efforts.

HOW IT WORKS: When a crime scene investigator locates evidence such as a blood stain, the Hands-Off Sampler Gun collects the sample with its universal sample-media adaptor. Thee investigator never has to touch the sample directly, and thereby avoids the potential for contaminating that sample. Once the sample has been collected, the investigator can testify in court that it was collected properly.

PROVING IT: The investigator will have proof to back up his or her testimony, because an onboard, 3D accelerometer -- a type of sensor that detects force -- records the sampling pattern, which proves that the sample was blotted, wiped or scraped properly. The gun’s force detector measures and records the pressure the investigator applies and compares it to the force necessary for proper collection of, for example, certain biological (DNA) samples. The gun also automatically records the sample’s location with internal Global Positioning System (GPS), measures the ambient temperature and takes a digital picture of the sample being collected. And here is an incorporated barcode reader and audio recorder to further establish proper chain of custody. All this information can be easily downloaded to a desktop computer through standard interfaces.

WHAT ARE MEMS: Accelerometers are an example of microelectro-mechanical systems (MEMS), devices that integrate electronic and moving parts onto a microscopic silicon chip. This integration makes such devices ideal for sensor technology. The term MEMS was coined in the 1980s. A MEMS device is usually only a few micrometers wide; for comparison, a human hair is 50 micrometers wide. Among other everyday applications, MEMS-based sensors are used in cars to detect the sudden motion of a collision and trigger release of the airbag. They are also found in ink-jet printers, blood pressure monitors, and projection display systems.

For more information about this story, contact:

Torsten Staab
Los Alamos National Laboratory
Tel: 505-665-7345
staab@lanl.gov


Note: This story and accompanying video were originally produced for the American Institute of Physics series Discoveries and Breakthroughs in Science by Ivanhoe Broadcast News and are protected by copyright law. All rights reserved.

Fausto Intilla's web site: www.oloscience.com