By Eamonn McGee, Senior Forensic Technologist, Centre of Forensic Sciences, Toronto, Ontario, Canada, and Technical Advisor, Ontario Provincial Police Provincial Emergency Response Team
ust over seven years ago, letters laced with anthrax spores killed five people in the United States, closed Congress and the Supreme Court, and crippled mail service for months. No other anthrax attacks have occurred since, but a flood of hoaxes and false alarms continues throughout North America. There are likely to be more white-powder events as a form of protest against the current economic recession. Mail threats are criminal events, and all white-powder calls may become police matters in the future.
Unknown powders, hazardous liquids, and gases are now routinely tested on-site using a wide range of portable instruments. The testing is usually performed by highly trained specialized teams, but not always, since portable instruments are marketed as easy to use, even for operators without a scientific background. However, many portable instruments are not good at identifying chemical mixtures despite the marketing claims.
Two operators using a portable GC-MS in a hot zone
Photo courtesy of the Centre of Forensic Sciences Toronto
The idea of placing portable equipment in the hands of specialized law enforcement teams or frontline police officers is appealing, but is it realistic to turn police officers into chemists? Placing sophisticated instruments that detect hazardous chemicals into the hands of law enforcement personnel is not without challenges and concerns.
One solution to the portable equipment problem is creating a mutually beneficial partnership between a forensic science laboratory and a specialized law enforcement team. Agencies that have a specialized response team, departments that are planning on forming a new team, or one that has frontline personnel who currently use portable instruments need to consider the advantages and limitations of field analysis.
Rapid Analysis for Rapid Response
Portable instruments such as Fourier Transform Infrared Spectroscopy (FTIR) and gas chromatography/mass spectrometry (GC/MS) deliver an analytical result, whereas a detector such as a gas monitor or a chemical agent monitor provides a presence or absence response. The post-9/11 years have seen unprecedented development in lightweight, sensitive, and fast portable detectors and instruments that are available to the military, first responder, and law enforcement communities. These technologies can be used to rapidly screen and identify a wide range of hazardous materials including white powders, explosives, drugs, toxic industrial chemicals, chemical warfare agents, biological agents, and radioactive substances.
These field technologies offer an attractive alternative to the traditional approach of collecting samples at a scene for subsequent laboratory analysis, thereby providing the data to make more rapid decisions regarding threat levels and health and safety. Law enforcement agencies are putting these new technologies to use at airports, public events, white powder calls, clandestine explosives and drug labs, and major emergency incidents.
Portable FTIR can give fast results that can be used to make critical decisions regarding health
Photo courtesy of the Centre of Forensic
Thinking Outside the Black Box
Field analysts may be tasked with detecting or identifying one of thousands of chemicals, in solid, liquid, and gaseous forms in the field; some are hazardous and some are not. There is no one magical “black box” instrument that can detect or identify all chemicals at all concentrations; a combination of complementary instruments with different purposes is required.
Two significant differences exist between the laboratory and the field analysis: the analysis and reporting time frames. The lab analyst usually has enough time to run enough tests to unambiguously identify a chemical or a mixture of chemicals, fully evaluate the results, confer with colleagues, consult the scientific literature, or repeat the tests.
In contrast, the field analyst is expected to generate results quickly, then interpret and explain them so that the decision maker can use the information to confidently make immediate decisions. Is the white powder cocaine or a homemade peroxide-based explosive? While cocaine does not pose an immediate danger, a peroxide-based explosive may require a building’s mass evacuation.
It is important to have a means of assessing the risk posed by unknown powders in the field. This amount of homemade peroxide-based explosive is enough to blow a
Photo courtesy of the Centre of Forensic Sciences Toronto
Lab-quality data may or may not be required on-site. But field operators must understand their instruments’ capabilities and limitations, so they can produce reliable, useful, and defensible results.
The performance and use of portable instruments in the emergency response field have been largely unregulated; however, this situation is changing. For example, the National Fire Protection Association (NFPA) 472 Standard for Competence of Responders to Hazardous Materials/Weapons of Mass Destruction Incidents includes minimum competency levels for awareness-level personnel (individuals who in the course of their normal duties might be first on the scene) and responders to emergencies involving hazardous materials and weapons of mass destruction.
Operator competency is the most important aspect of any field analysis; the NFPA standard states that responders with assigned chemical agent-specific tasks in an emergency should be able to identify the correct detection device to use based on observations, deploy the device, and interpret the readings. If the sample going into the portable instrument is incorrect, then the adage “garbage in, garbage out” applies.
Saving with Chemical Analysis
How can law enforcement agencies obtain the technical expertise and ongoing training required to competently perform chemical analysis in the field without spending large amounts of money? Many police agencies have collaborative relationships with forensic labs, and these labs make good partners. However, forensic labs are typically not equipped to receive or handle chemical, biological, radiological, nuclear, and explosive (CBRNE) samples, and useful forensic information may be lost if these samples cannot be accepted and analyzed. But a department can develop a partnership for CBRNE analysis.
Such a partnership was formed in Ontario in 2004 between the Ontario Provincial Police (OPP) Provincial Emergency Response Team (PERT) and the Centre of Forensic Sciences (CFS). The OPP is one of North America’s largest deployed police services, and the PERT team consists of 28 highly trained officers prepared to respond to CBRNE threats. PERT has a very broad mandate, expected to provide expertise in CBRNE response as well as policing. CFS supports PERT by providing ongoing training, reachback, scene attendance; evaluating existing and new technologies; and providing access to experts in different scientific disciplines. PERT screens potential CBRNE samples before they are submitted to CFS for analysis. Working together ensures that the partners know and trust each other’s abilities.
It is not realistic to expect that police officers can be trained to be chemists or that chemists can be trained to be emergency responders; however, the PERT-CFS partnership brings together the specialized skills of both worlds in a mutually beneficial and cost-effective partnership. ■