The approach and methodology used in the determination of the type of cargo containing concealments of commercial quantities of narcotics such as cocaine and heroin is described. This high-risk cargo enters the United States through border crossings at land, seaports and airports. The volume and variety of cargos make it a complex and challenging task for the U.S. Customs Service.

New techniques and sensors to identify the molecular, chemical, or elemental structures unique to drugs are being developed under several national programs. However, the challenge faced by U.S. drug enforcement and Customs officials goes far beyond the simple technical capability to detect an illegal drug. Entry points into the U.S. include ports, border crossings, and airports where cargo ships, vehicles, and aircraft move huge volumes of freight. Current technology and personnel are able to physically inspect only a small fraction of the entering cargo containers. The complexities of how to best utilize new technology to aid the detection process and yet not adversely affect the processing of vehicles and time-sensitive cargo is the challenge faced by these officials. This paper describes an ARPA sponsored initiative to develop a simple, yet useful, method for examining the operational consequences of utilizing various procedures and technologies in combination to achieve an `acceptable' level of detection probability. Since Customs entry points into the U.S. vary from huge seaports to a one lane highway checkpoint between the U.S. and Canadian or Mexico border, no one system can possibly be right for all points. This approach can examine alternative concepts for using different techniques/systems for different types of entry points. Operational measures reported include the average time to process vehicles and containers, the average and maximum numbers in the system at any time, and the utilization of inspection teams. The method is implemented via a PC-based simulation written in GPSS-PC language. Input to the simulation model is (1) the individual detection probabilities and false positive rates for each detection technology or procedure, (2) the inspection time for each procedure, (3) the system configuration, and (4) the physical distance between inspection stations. The model offers on- line graphics to examine effects as the model runs.

Detection of trace quantities of illicit drugs residue is one method to indicate that a shipment of contraband drugs may be present aboard vessels, either concealed in various aspects within the vessel or in the cargo and containers being transported. The application of available high speed, ultra sensitive analytical technologies to detect trace quantities presents unique problems in their acceptance and use as operational tools. Based upon results of a nine month field trial, the U.S. Coast Guard Research and Development Center has developed guidelines, procedures and protocols for routine field use of two narcotic detection systems. Proper training coupled with strict adherence to these guidelines, procedures and protocols has resulted in the acceptance of the IONSCAN^TM and SENTOR^TM narcotic detection systems as evidence in three Federal court actions. This paper presents the results of our studies which guided the drafting of these procedures, protocols and guidelines. The resulting increased confidence in the analytical data obtained with the use of these two systems by operational personnel will also be discussed.

A study has been performed to determine the mass of RDX and the particle size distribution of composition 4 residue deposited by fingerprint transfer. Particle residues of composition 4 deposited on to smooth polyethylene films were studied. Six sample sets of fifty sequential prints were examined in the study. Mass of RDX was determined by gas chromatography with electron capture detection for give sample sets. The particle size distribution of composition 4 residues was determined by microscopic examination for the sixth set. Results indicated that although there was variability across the series in the amount of RDX for a particle sample sequence number, results corroborated well with preliminary studies conducted by NRC of Canada. In a series of successive thumb prints laid down sequentially after an initial imprint on to C-4 explosive, the residue RDX contamination ranged from milligram levels for the first few prints to nanogram levels for fortieth to fiftieth print. Moreover, a log-log correlation was established between fingerprint number and mass of RDX present. Microscopic results indicated that the measured particle size distribution appears bi-modal in nature and is lognormally distributed.

A method has been developed to study the adhesion of particles on a surface and the gas velocity needed to overcome the adhesion and dislodge the particle from the surface. Experiments have been performed to determine the minimum detachment velocity for particles deposited on a surface by gravitational settling and by finger print transfer. Particles of Arizona road dust and SiO₂ were deposited on smooth, and frosted glass for the study. In addition, composition-4 particles transferred via finger print onto polyethylene films were also studied. Results indicate that gas velocities in the 1 - 100 m/s range were needed to detach particles in the 10 - 300 micrometers range from these surfaces. Generally, the larger the particle size, the lower is the detachment velocity. Particles transferred via finger print were found to adhere to surfaces more tightly than similar particles deposited by gravitational settling, and surface roughness tend to decrease the detachment velocity.

Gaschromatography (GC) is a widespread method to separate components in complex mixtures. The separation in the gasphase follows three main principles: - separation by molecular sieves where the molecules are selected by their size - separation on solid phases using adsorption forces - separation on liquid films (stationary phases) using different solubilities of the molecules in the liquid phase. Normally the mixtures are injected as a vapour or liquid (which is vaporized in the injectorblock) on a GC-column. The components are transported by the mobile phase (carrier gas) through the column which is packed with solid carrier particles coated with a liquid film.

Two new instruments have been developed for the detection of explosives, the EVD-8000 and EVD-3000. The EVD-8000 is equipped with multi-capillary GC columns terminating to a sensitive electron-capture detector. The EVD-3000 is a novel approach for rapid detection of explosives. It is based on the specific thermal redox reaction of explosive molecules, resulting in a rapid response time of less than 8 seconds. Both instruments have facilities for processing vapor and swap samples.

We have developed an instrument based on Micro Gas Chromatography ((mu) GC) for rapid, handheld detection of vapor signatures from contraband drugs in cargo containers. For this application, a key requirement is the ability to distinguish the vapor signatures of contraband drugs against the highly variable chemical backgrounds encountered in cargo containers. To achieve this, we split the sample and run it simultaneously on two (mu) GCs with different stationary phases using correlated column chromatography. This effectively expands `detection space' and greatly enhances the chemical selectively. As part of this effort, we have also developed an extensive correlated chromatography database of chemical vapor signatures for both contraband drugs and representative backgrounds obtained by sampling incoming cargo containers under the supervision of U.S. Customs inspectors. Our experience shows that significant vapor buildup occurs in these containers resulting in strong and variable chemical backgrounds. Typical GC signatures observed have 10 - 20 strong components with a variable number of weaker components. The signatures reflect the very large variation in the contents and extent of packing of cargo containers, and show that vapor-based chemical detectors will require a large dynamic range to be effective. Gas chromatography is well suited for this. Furthermore it appears that a correlated (mu) GC instrument can provide rapid, handheld detection which fits into existing operational scenarios for the inspection of cargo containers for contraband.

The detection by chemical sensors of explosive devices in a terrorist or contraband scenario usually involves the acquisition of material in the vapor or solid form. Whether in the vapor form in ambient air or in solid form in a matrix of innocuous material, the chemical compounds may be present at very low concentrations or may be present in concentrations higher by orders of magnitude. In this study, a characterization of a tandem mass spectrometer detection system has been made to evaluate a variety of parameters as it relates to explosive chemicals in both the vapor and solid phases. In particular, a range of concentrations of standard solutions of RDX, PETN and TNT have been injected in determine the sensitivity, dynamic range, and lower level of detection of the SCIEX contraband tandem quadrupole mass spectrometer. Techniques for the introduction of samples include heated nebulization and direct injection/thermal desorption from a real time sampler belt. As well, explosive vapors produced by a special generator were injected in a 1 l/min stream of room air and used to characterize instrumental performance. Solid material was presented in a form simulating fingerprint material and then transferred to the detector using a real time sampling system and then thermally desorbed into the mass spectrometer ionization chamber.

Several Law Enforcement Agencies, especially the U.S. Coast Guard R&D Center, have conducted field tests and evaluations of the Thermedics Detection SENTOR drug detector during the past several years. The system has provided valuable information for interdiction operations and has been accepted as evidence in court. While it has been shown to be a highly selective detector, the field tests have revealed that a few specific interferences exist which cause some difficulties in data interpretation. Based on the results obtained from these numerous studies, several different gas chromatography columns with various coatings were evaluated to minimize the impact of these interferences on data interpretation. Gas chromatographic evaluations were conducted employing both laboratory and real world samples. During these column evaluations the SENTOR operating conditions were readjusted to improve the selectivity of the system and these improvements have increased the reliability of the system and reduced the impact of interferences on data interpretation. The improvement of SENTOR will be described. The development of the chromatography will be detailed with examples provided. Data from field and laboratory studies will be presented and discussed.

The techniques used to detect, measure and monitor chemicals in liquids, gases and solids are being developed in response to the demand for greater sensitivity and specificity needed to detect trace chemicals. Biosensors and immunoassays, due to their inherent sensitivity and specificity are excellent candidates for inclusion in inspection systems. This discussion will review the fundamentals of biosensors and immunoassays, their advantages and disadvantages, the current state-of-the-art as indicated by published research and how and where they can be included in cargo inspection technologies.

In a joint project of Deutsche Aerospace, Boehringer Mannheim and the University of Potsdam portable devices for the detection of illegal drugs, based on biosensor technology, are being developed. The concept enrichment of the drug from the gas phase and detection by immunological means. This publication covers the description of our objectives, preparatory work and results concerning enrichment of drugs from the gas phase. Vapor pressures of cocaine and cannabinoids have been determined. A test gas generator has been constructed which allows for reproducible preparation of cocaine concentrations between 2 ng/l and 2 pg/l. Coupling of a thermodesorption unit with GC/MS has been established for reference analysis. As another analytical tool, an ELISA with a lower detection limit of about 0,5 pg cocaine/assay has been developed. Applying fleece-type adsorbers, enrichment factors for cocaine in the range of 10⁵ have been realized. No significant interference was found with potentially disturbing substances.

In a joint project of Deutsche Aerospace, Boehringer Mannheim and the University of Potsdam portable devices for the detection of illegal drugs, based on biosensor technology, are being developed. The concept enrichment of the drug from the gas phase and detection by immunological means. This publication covers the development of specific antibodies and various detection procedures. Antibodies with a high affinity for cocaine have been developed with the aid of specially synthesized immunogens. A competitive detection procedure with biosensors based on optical grating couplers and applying particulate labels has been established, showing a lower detection limit of 10^-10 mol/l for cocaine. Additionally, a combination of a displacement-immunoreactor and an enzymatically amplified electrode was investigated, which at present still suffers from insufficient sensitivity of the immunoreactor. An alternative, fleece-matrix based test procedure, where enrichment and detection steps are integrated in a single unit, is promising in terms of simplicity and sensitivity. A simple swab-test for the detection of cocaine at surfaces has been developed, which has a lower detection limit of about 10 ng and which can be performed within one minute.

Pure nuclear quadrupole resonance (NQR) of ¹⁴N nuclei is quite promising as a method for detecting explosives such as RDX and contraband narcotics such as cocaine and heroin in quantities of interest. Pure NQR is conducted without an external applied magnetic field, so potential concerns about damage to magnetically encoded data or exposure of personnel to large magnetic fields are not relevant. Because NQR frequencies of different compounds are quite distinct, we do not encounter false alarms from the NQR signals of other benign materials. We have constructed a laboratory prototype NQR explosives detector which interrogates a volume of 300 liters (10 ft³). This paper presents abbreviated results from a demonstration of the laboratory prototype NQR explosives detector conducted at the Federal Aviation Administration Technical Center in May 1994 on RDX-based explosives.

Interest in non-invasive, non-hazardous, bulk detection technologies for narcotics interdiction has risen over the last few years. As part of our continuing research and development programs in detection of narcotics and explosives using sensitive magnetic measuring devices, we present the first commercially available prototype Quadrupole Resonance (QR) scanner for narcotics detection. The portable narcotics detection system was designed in modular form such that a single QR base system could be easily used with a variety of custom detection heads. The QR system presented in this paper is suitable for scanning items up to 61 X 35 X 13 cm in size, and was designed to scan mail packages and briefcase-sized items for the presence of narcotics. System tests have shown that detection sensitivity is comparable that obtained in laboratory systems.

This paper describes the plan for the assessment of the second generation X-ray inspection systems based on direct transmission, dual view, dual energy and backscatter technology. The purpose of this assessment is to determine the performance of each of these systems based on the analysis of the data on the detection of cocaine and heroin. The results of this assessment will be of immense value to law enforcement agencies in helping them select the type of X-ray inspection system best suited for their particular application.

The Non-intrusive Inspection Technology Testbed is a high-energy radiographic imaging system for the detection of contraband in intermodal containers. X-ray images are analyzed with a complement of computer-based enhancement tools so that a decision can be made whether to pass the container into the stream of commerce or recommend that it be opened and searched. This paper applies signal detection theory to the analyst's task and reports on a study that explored the relationship between the Embedded Figure Test (EFT) and performance in detecting contraband. It was found that the EFT score and the performance measure were correlated (r equals -0.58, p equals 0.023). A replication of this study using airport X-ray screeners and X-ray proficiency ratings by their supervisors also showed a correlation (r equals 0.44, p < 0.04). It was concluded that the EFT predicts the ability of an operator to find contraband in an X-ray image. Recommendations were made on the application of signal detection theory to the operation of the imaging system.

Cargo examination systems will integrate multiple sensors because single sensor systems can be defeated. Trials with multiple sensors have also resulted in both increased inspection accuracy and throughput. The traditional integration point for multiple sensor outputs is paper. Cargo inspection analysts must evaluate a file folder containing many interrelated pieces of paper within minutes. File folders with paper have proven to be an obsolete medium for complex data presentation. A computer-based system, ExamFolder Technology Integrator uses an open architecture to receive input from multiple sensors treating each input data set as a document. Documents from any sensor, even those yet to be developed, can be collected, structured, and displayed to the analyst. The documents include, but are not limited to: digital data, imagery, video and digitized voice. The system structures the documents for scrutinizing manifested cargo, shipper, shipping agent, carrier, broker, forwarder and consignee histories. This reduces pressure on the analyst for timely completion of the inspection. The ExamFolder Technology Integrator is an efficient, sensor-vendor independent, computer screen-based, cargo inspection system providing meaningful information to the cargo analyst.

A recently developed computer system is described which automatically analyzes X-ray images of carry-on baggage to identify potential threat-type objects for airport security. The system uses a PC front-end and a MIMD parallel processing unit for image processing and analysis. The system is capable of real-time operation and is capable of over 0.5 GFLOPS. The system is able to identify most threat with over 95% accuracy, and a false alarm rate of about 13%. This image analysis system could be relatively easily modified to be used for cargo inspection applications.

The Advanced Research Projects Agency (ARPA) Nonintrusive [Cargo] Inspection Technology Testbed, located in the port of Tacoma, Washington, began operation on 21 May 1993. The testbed is a part of the Department of Defense Counterdrug Research and Development Program. It is used to evaluate the ability of existing inspection technologies, as well as new technologies and prototype systems, to detect contraband, primarily drugs, hidden in large intermodal cargo containers and vehicles without the need to open them or manually remove the cargo. Currently, a dual-image, high-energy radiographic imaging system and an advanced information processing and display system are being evaluated at the testbed. Work is under way to install and begin testing of a pulsed fast neutron analysis cargo inspection system in early 1995. The testbed can also accommodate other sensors such as particle/vapor detection systems. The testbed was designed, constructed, and is now operated for ARPA by Analytical Systems Engineering Corporation. This paper provides a brief overview of the testbed, the high-energy radiographic imaging system, the information processing and display system, and the test program.

An x-ray-based cargo inspection system test program is being conducted at the Advanced Research Project Agency (ARPA)-sponsored Nonintrusive Inspection Technology Testbed (NITT) located in the Port of Tacoma, Washington. The test program seeks to determine the performance that can be expected from a dual, high-energy x-ray cargo inspection system when inspecting ISO cargo containers. This paper describes an intensive, three-month, system test involving two independent test groups, one representing the criminal smuggling element and the other representing the law enforcement community. The first group, the `Red Team', prepares ISO containers for inspection at an off-site facility. An algorithm randomly selects and indicates the positions and preparation of cargoes within a container. The prepared container is dispatched to the NITT for inspection by the `Blue Team'. After in-gate processing, it is queued for examination. The Blue Team inspects the container and decides whether or not to pass the container. The shipment undergoes out-gate processing and returns to the Red Team. The results of the inspection are recorded for subsequent analysis. The test process, including its governing protocol, the cargoes, container preparation, the examination and results available at the time of submission are presented.

Increasing world trade, besides others, means to take care for a continuous flow of cargo. This is important if politicians want to improve a country's economy. There are a lot of technical means assisting to speed up the handling of the huge amount of cargo. But, just taking care for a fast handling of merchandise means to support the fraudulent and often dangerous activities of criminal syndicates and organizations. Responsible governmental officials are now supported in fulfilling their difficult task.

A new, large-scale, very low dose cabinet X-ray system has been installed at the newly- completed commercial border crossing facility located at Otay Mesa, California, a few miles south of San Diego. The system has two separate 450 kV flying-spot X-ray sources, each with its own sets of transmission and backscatter detectors. The sources are located below grade, and are arranged to illuminate the undercarriage and the sides of the truck symmetrically from below. This geometry allows close proximity of the sources to the truck, resulting in improved imaging performance. The point-by-point mapping sequence of a flying-spot scan enables both transmission and backscatter images to be obtained simultaneously. The system is intended primarily for the inspection of empty trucks, but it can also be used to inspect loaded vehicles up to 80,000 pounds gross weight and 65' long. It will be operated by U.S. Customs Service personnel. The system and its planned operations are described. Key issues involve vehicle and driver logistics, vehicle handling within the X-ray facility, throughput, ease of use, and radiation safety. The results of radiation survey measurements and initial test images will be presented.

A portable hand held hidden substance detector has been developed and manufactured. Neutrons from a californium-252 source are emitted through the front face of the Compact Integrated Narcotics Detection Instrument (CINDI) and penetrate dense compartment materials with little change in energy, but are backscattered by hydrogen rich materials such as drugs. These backscattered neutrons can be readily detected. CINDI incorporates a highly sensitive detection scheme which permits the use of weak radioactive sources for safety without compromising detectability. CINDI is able to detect hydrogen-dense materials most effectively directly behind panels made of steel, wood, fiberglass, or even lead-lined materials. This makes it useful for inspecting marine vessels, ship bulkheads, automobiles, structure walls, or small sealed containers. The present CINDI version selectively detects hydrogen rich substances only. The new technique will detect both neutrons and gamma rays simultaneously. The backscatter mechanism of gamma rays and neutrons are sufficiently different that they complement each other and lead to a higher likelihood of identifying the concealed material.

In the area of security and surveillance technologies, the problem of the arrival in Canada of illegal and undesirable ship and truck cargo loads is steadily increasing. As the volumes of cargo arrivals increase so do the Immigration and Customs problems related to the determination of the validity of those cargo contents. Of special concern to Immigration Control Authorities around the world is the emerging and increasing trend of illegal smuggling of human beings hidden inside of shipping containers. Beginning in 1992, Immigration Control Authorities in Canada observed an escalation of alien people smuggling through the use of cargo shipping containers arriving in the Port of Montreal. This paper will present to the audience the recently completed Immigration Canada Human Occupancy Detection project by explaining the design, development and testing of human occupancy detectors. The devices are designed to electronically detect the presence of persons hiding inside of shipping containers, without the requirement of opening the container doors. The human occupancy detection concepts are based upon the presence of carbon dioxide or other human waste characteristics commonly found inside of shipping containers.

The IONSCAN^TM operating parameters for detection of benzoic acid and acetic acid have been optimized. Various materials and chromatographic coatings were investigated for the vapor preconcentration of benzoic acid, acetic acid and cocaine. Limited field trials indicated a possibility of detecting benzoic acid from seized cocaine shipment. From the laboratory investigation and some field tests it has been shown that cocaine free base is present in cocaine hydrochloride in sufficiently high concentration to provide constant supply of cocaine vapors in the headspace for a long period of time.

Three techniques (API, PFNA and PFTNA) are described and compared in this brief review of neutron based technologies for the detection of contraband in cargo containers. It appears that the role that these techniques can play in the detection of contraband in Customs, airline security and physical security applications remains to be demonstrated. However, their utilization in the fields of non-proliferation, arms control and disarmament, radwaste remediation and pollution control seems more straight forward since the issues of thruput and radiation safety are not so critical.

Non-invasive inspection systems based on the use of fast neutrons are being studied for the inspection of large cargo containers. A key advantage of fast neutrons is their sensitivity to low-Z elements such as carbon, nitrogen, and oxygen, which are the primary constituents of explosives and narcotics. The high energy allows penetration of relatively large containers. The pulsed fast-neutron analysis (PFNA) technique is currently the baseline system. A workshop on the PFNA technique involving industrial, government, and university participants was held at Argonne National Laboratory in January 1994. The purpose of this workshop was to review the status of research on the key technical issues involved in PFNA, and to develop a list of those areas where additional modeling and/or experimentation were needed. The workshop also focused on development of a near-term experimental assessment program using existing prototypes and on development of a long-term test program at the Tacoma Testbed, where a PFNA prototype will be installed in 1995. A summary of conclusions reached at this workshop is presented. Results from analytic and Monte Carlo modeling of simplified PFNA systems are also presented.

Compton scattering and photoelectric absorption of gamma rays are used as indicators of material electron density and mean atomic number, respectively. These indicators are shown to be adequate for discriminating explosive materials from other organic or polymer materials of similar mass densities. A transmission-scattering map is shown, experimentally and by Monte Carlo simulation, to provide a useful and simple indicator for the presence or absence of explosives.

An accelerator-based, active, pulsed, interrogation system capable of non-destructive, elemental analysis from secondary gamma-ray emissions is being developed for various inspection applications. The system consists of a very narrow pulsed, electron accelerator (> 8 MeV) for photoneutron production and a multiple channel, gamma-ray detection system capable of ultra-fast detection. This system has applicability to cargo container inspections. Advantages of the system include use of highly penetrative, energetic, interrogating X-rays, compatibility with existing X-ray inspection systems, capability of large neutron production yield from the pulsed accelerator, ability to induce a volumetric, tailored neutron source spectrum within or very near the containers, and most importantly, the spectrometry capability of a ultra-fast, gamma-ray detection system. The portable detection system is described which has been designed to acquire multiple, single gamma-ray events (up to 40 MHz between each accelerator pulse) from neutron inelastic scattering (starting from within 100 ns after an accelerator pulse) and neutron capture interactions. The system and its overall operational requirements are described. Experimental results, using a 50 ps electron accelerator pulse and selected inspected objects, are presented along with numerical predictions and system characterizations.

Useful detection of illegal cocaine shipments requires a means of performing rapid, on-site chemical analysis in a relatively non-intrusive manner. The sampling and analysis of the vapors emanating from the cocaine and cocaine hydrochloride may offer an attractive approach to detection. An immediate problem which makes this approach difficult is the very low vapor pressure of cocaine. The low vapor pressure of cocaine limits the available quantity for detection. There is the potential, however, for chemicals with higher vapor pressures to be present from the cocaine. If the presence of such chemicals is demonstrated to have a high correlation with the presence of cocaine and/or cocaine hydrochloride, their detection would offer a valuable tool for the detection of cocaine shipments. The chemicals that would have a high correlation with the presence of cocaine can be introduced from several sources, including the coca leaves from which naturally occurring alkaloids are extracted, cocaine purification processes, and cocaine degradation. Each of these sources has been examined in an effort to identify key compounds for cocaine detection. The purpose of this paper is to describe these efforts, and to summarize a program which is currently underway to accomplish the identification ofchemicals which may be useful for cocaine detection using headspace analyses.

Detection of illicit cocaine hydrochloride shipments can be improved if there is a greater understanding of the identity and quantity of volatile compounds present. This study provides preliminary data concerning the volatile organic compounds detected in a limited set of cocaine hydrochloride samples. In all cases, cocaine was one of the major volatile compounds detected. Other tropeines were detected in almost all samples. Low concentrations of compounds which may be residues of processing solvents were observed in some samples. The equilibrium emissivity of cocaine from cocaine hydrochloride was investigated and a value of 83 parts-per-trillion was determined.

An eight month trial of a system capable of checking every bag from a particular flight for the presence of narcotics has been carried out at a major UK airport. The British Aerospace CONDOR tandem mass-spectrometer system, fitted with a real-time sampler, was used to check in-coming baggage for a range of illegal drugs. Because of the rapid sampling and analysis capability of this instrument, it was possible to check every bag from a flight without delay to the passengers. During the trial a very large number of bags, from flights from various parts of the world, were sampled. A number of detections were made, which resulted in a number of seizures and the apprehension of a number of smugglers.

Measurements were made at the Otay Mesa, CA, border crossing between November 30 and December 4, 1992, to demonstrate proof of concept and the practicality of using potassium 40 (K40) gamma emissions to detect the presence of marijuana in vehicles. Lawrence Livermore National Laboratory personnel, with the assistance of the EPA, set up three large volume gamma ray detectors with lead brick shielding and collimation under a stationary trailer and pickup truck. Measurements were performed for various positions and quantities of marijuana. Also, small quantities of marijuana, cigarettes, and other materials were subjected to gamma counting measurements under controlled geometry conditions to determine their K40 concentration. Larger quantities of heroin and cocaine were subjected to undefined geometry gamma counts for significant K40 gamma emissions.

British Aerospace has established an analysis service for UK Police and Customs authorities based on its CONDOR contraband detection system. The service has been successfully used to detect drug traces in cars, buildings and on bank notes. Recent legislation in the UK allows for the confiscation of the proceeds of drug related crime. The service has been used to assist in the confiscation of large sums of money, presumably drug related, being taken out of the country. A range of drugs has been detected on suspect money, whereas money in general circulation, obtained from the Bank of England, has been shown to be free from contamination. The way in which samples are collected and analyzed, and typical results are discussed.

Current explosive material detection techniques are based solely on shape recognition, thus the explosive substances can easily be concealed and escape detection. Luggage detection/inspection system modifications are needed to allow for the chemical composition analysis of the luggage content. We report the design of a detection/inspection system which is based on both tomography and spectroscopy for the detection and measurement of Chlorine, Oxygen, Nitrogen and Carbon (CLONC-TOMOSCOP). Spectroscopy is used to determine exactly any explosive composition of CLONC species in the luggage content, while tomography combined with spectroscopy provides a unique detection capability in which explosive materials are both localized and detected.

We are investigating the issues involved in requirements definition for narcotics interdiction: how much of a particular signature is possible, how does this amount change for different conditions, and what is the temporal relationship in various scenarios. Our approach has been to simulate numerically the conditions that arise during vapor or particulate transport. The advantages of this approach are that (1) a broad range of scenarios can be rapidly and inexpensively analyzed by simulation, and (2) simulations can display quantities that are difficult or impossible to measure. The drawback of this approach is that simulations cannot include all of the phenomena present in a real measurement, and therefore the fidelity of the simulation results is always an issue. To address this limitation, we will ultimately combine the results of numerical simulations with measurements of physical parameters for inclusion in the simulation. In this paper, we discuss these issues and how they apply to the current problems in narcotics interdictions, especially cargo containers. We also show the results of 1D and 3D numerical simulations, and compare these results with analytical solutions. The results indicate that this approach is viable. We also present data from 3D simulations of vapor transport in a loaded cargo container and some of the issues present in this ongoing work.

A transmission quadrupole mass spectrometer has been incorporated in an integrated trace vapor detection system. The system includes high performance sample acquisition and inlet provisions to maximize detectability at very low levels. To characterize performance credibly, a precision sample generator with a down stream switching capability at levels below part per billion has been constructed. Construction and operation is reported.

A new patented Ion Trap Mobility Spectrometer (ITMS) design is presented. Conventional IMS designs typically operate below 0.1% efficiency. This is due primarily to electric field driven, sample ion discharge on a shutter grid. Since 99.9% of the sample ions generated in the reaction region are lost in this discharge process, the sensitivity of conventional systems is limited. The new design provides greater detection efficiency than conventional designs through the use of an `ion trap' concept. The paper describes the plasma and sample ion dynamics in the reaction region of the new detector and discusses the advantages of utilizing a `field-free' space to generate sample ions with high efficiency. Fast electronic switching is described which is used to perturb the field-free space and pulse the sample ions into the drift region for separation and subsequent detection using pseudo real-time software for analysis and display of the data. Many applications for this new detector are now being considered including the detection of narcotics and explosives. Preliminary ion spectra, reduced mobility data and sensitivity data are presented for fifteen narcotics, including cocaine, THC and LSD are reported.

Although canines are routinely used to search for both explosives and illicit drugs, little is actually known about the detection thresholds of dogs for these substances. Federally funded studies have been initiated at Auburn University to characterize these threshold levels and to determine which chemical substances canines are cueing on. As a part of this study, a specialized vapor generator has been designed to deliver odorants to canines. The study described herein characterizes the output of this vapor generator, called an Olfactometer, utilizing multiple sensitive detection methods. For this study, an independently calibrated ion mobility spectrometer and a SCIEX tandem quadrupole mass spectrometer were used to characterize the output of the Olfactometer with the explosive C-4 as a target substance. It was found that the primary chemical in the system was cyclohexanone, a solvent used in the purification process for C-4. No trace of RDX, the explosive compound, could be found in the system, expect in the generator reservoir itself. This study suggests several improvements that could be made to the Olfactometer, including the implementation of a new post use purging procedure to prevent cross contamination from study to study. Additionally, data suggest that dogs may in fact be cueing on the presence of cyclohexanone mixed with hydrocarbons rather than the explosive itself.

Pulsed Fast Neutron Analysis (PFNA) is a technique which uses a collimated pulsed beam of fast neutrons to excite the nuclei of common elements in bulk materials. Direct imaging of the elemental contents of the material is accomplished by using time-of-flight analysis to identify the position of the interactions and gamma-ray spectroscopy to identify the elemental gamma rays. From the ratios and absolute measurements of elemental abundances the identification of the material can be deduced. The PFNA Cargo Inspection System uses a volume type negative ion source and a double drift bunching system to create an intense beam of nano-second bunched negative deuterium ions which, after acceleration to around 6 MeV, impinge on a deuterium gas target producing pulsed neutrons. A unique high speed data acquisition system digitizes and analyzes the time-energy data in real time. Experimental studies and computer simulations were extensively employed to characterize and optimize the design parameters of the system. The system described is scheduled for full scale laboratory testing in the fall of 1994 and for field testing at a Government Testbed in Tacoma, WA in 1995.

Effective, routine field use of the K920B `Buster' Contraband Detector has been achieved as the result of a program of close cooperation between the development engineers and the field users wherein the field users were brought in as a part of the development process. Initial field application attempts were unsuccessful when single units, with only basic training, were shipped to a single port of entry for one or two months of experimental use and where then shipped on to another port. After review of the initial experience, the field application development concept was changed. The program prospered when multiple units, combined with comprehensive training, were shipped to a few selected ports on a permanent basis and assigned to interested and innovative field inspectors who were given the challenge and the opportunity to develop field application procedures. The field users, given freedom to experiment, have expanded the initial concept of the Buster Contraband Detector, developing unforseen techniques to achieve unexpected goals. As a result of the close cooperation between the development engineers and the field users, this new high technology device has now become a commonplace and effective field tool.

The Counterdrug Technology Assessment Center (CTAC) was established in 1990 within the Office of National Drug Control Policy to provide a central organization for overseeing research and development for drug law enforcement technology and for technology to support medical research programs in drug abuse treatment and rehabilitation research. One of the primary missions of CTAC from its inception was to transfer many of the United States technological developments for nuclear treaty verification, chemical weapons inspections and explosive ordnance detection and disposal to counterdrug interdiction operations. In this respect, CTAC coordinates the national effort to develop prototype technologies for an advanced generation, nonintrusive cargo inspection system. This paper provides the highlights of the United States technology prototype development program for nonintrusive inspection of cargo containers for illicit drugs.

A neutron transmission/attenuation spectrometer has been used to obtain the neutron attenuation signature of cocaine, heroin, hashish, methamphetamine, pipe tobacco and chewing tobacco. A pulsed `white neutron' source was created by bombarding a thick beryllium target with a 5 MeV pulsed deuteron beam. The neutron intensity was measured from about 0.75 MeV to about 4 MeV with the suitcase in and out of the neutron beam to determine the neutron attenuation. Experiments were performed for drugs and tobacco alone and when imbedded in an `average suitcase'. The experimentally determined neutron attenuation curves were used to determine the atomic ratios C/O, N/O, and H/C through the samples using measured neutron cross sections.

In six companion papers we discuss a capability for X-ray tomographic spectrophotometry at three energy ranges to observe defects (in a general sense) in various systems using a novel X- ray optical and photometric approach. We describe new types of thin-film X-ray reflecting filters to provide energy-specific optical trains, inserted into existing X-ray interrogation systems. That is complemented by performing tomographic imaging at a few, to several, energies in each case. That provides a full tomographic and spectrophotometric analysis. Defects and inclusions can then be detected, and localized, discriminated, and classified, so that they may be dealt with by excision, and replacement with benign system elements. We analyze the principles of the technique as it leads to the design of three systems: The first operates at X-ray energies of 1 - 10 KeV. It deals with defects in microelectronic integrated circuits, which destroy the devices' electronic functionality, while they are still at the wafer stage of microelectronic device manufacture. Repair techniques can then be directed to excise the defects in situ, restore the functionality of the I/C's, and bring the effective manufacturing wafer yield to 100%. The second operates at X-ray energies of 10 - 30 keV. It deals with the defects in human tissue called tumors, which destroy the biological functionality of the organs that they inhabit. The chemical specificity and image resolution of the system will allow identification, localization, and mensuration of tumors without the need of biopsy. Then all measures necessary to plan effective therapies for the tumors. The third operates at X-ray energies of 30 - 70 keV. It deals with the defects in transportation systems which are represented by the presence of lethal objects (i.e., explosive devices) and contraband materials and objects in luggage and cargo. Steps can then be taken, for the excision of those objects, from the transportation system to restore its full functionality, guaranteeing the safe and legal passage of only those objects expected (to support the normal functions of society).