"The
Project SEED summer program gave me a chance to learn about research first hand."
This summer, thanks to Project SEED, over 130 economically disadvantaged high school students like Angela Odom had a chance to work and learn in a number of academic research labs throughout the U.S. Your contributions, which are used 100% for student sti pends, are needed for SEED to continue helping students prepare for making vitally im portant decisions about their future education and work.
Project S E E D ACS, 1155 16th St., N.W. Washington, D.C. 20036 Y e s , I'd like to help these students learn what is required for success as college students. Name: Address:
Contribution: D $50 Π $20 D Other
46A
Π $10
Environ. Sci. Technol., Vol. 16, No. 1, 1982
Benzothiazole was, in fact, being emitted from a low-level stack, whereas the aniline emissions shown in Figure 9 were generally fugitive emissions and, consequently, no im pingement point would be anticipated. Another interesting feature of the plots in these two figures is the slight jog in the path of each plume. The industrial buildings are situated in the bottom of a river valley and the jog in the plume path is caused by the valley wall. There is, however, a potential problem with this pollutant mapping procedure. The wind direction must remain relatively constant over the course of the transits. If the transits can be completed in a relatively short period of time, the problem of wind direction fluctuation is minimized. For example, the plume maps shown in Figures 9 and 10 included transits along seven roads to a distance of sev eral kilometers, yet required only 20 min to complete. Prognosis What does the future hold for mo bile mass spectrometry? In a phrase: "Mobile Triple Quadrupole Mass Spectrometry." Within the past few years the TAGA family has grown to include a triple quadrupole mass spectrometer system that also uses APCI techniques. This system can analyze components in mixtures without having to separate them for analysis. The first quadrupole selects up to five compounds; quadrupole two breaks up the fragments; quadrupole three detects the individual frag ments. The triple quadrupole instrument resembles closely the instrument il lustrated in Figure l with the excep tion that between the quadrupole and the detector, there are two additional quadrupoles in tandem. The first and third quadrupoles are active (they can be made mass-selective), whereas the second quadrupole is an RF-only quadrupole that acts as a total ion fil ter. When the second quadrupole is pressurized with a neutral gas such as Argon, ions passing through the first quadrupole are fragmented through a process termed collision-induced dis sociation. The fragments may then be mass-scanned by the third quadrupole. The combination of the real time class separation inherent in the APCI ion source and the fragmentation capa bilities of the triple quadrupole system will greatly help to identify unknown species in complex environmental matrices. One of these systems is slated for installation on a mobile platform early in 1982. Both low pressure CI and el
emental sources (which also permit instantaneous analysis of samples) are being developed and have begun to expand the capabilities of the system. We have just begun to explore the real-time monitoring capabilities of the mobile mass spectrometer system to solve environmental problems, and we anticipate that the technique will re ceive increased interest and wider ap plication over the next few years. Acknowledgment
This article was read for technical accuracy by A. P. Altschuller, U.S. Environmental Protection Agency, Research Triangle Park, N.C. 27711, and William H. Glaze, University of Texas-Dallas, Richardson, Tex. 75080. References ( 1 ) Huertas, M. L.; Fontan, S. Atmos. Environ. 1975,9, 1018. (2) "A Case Study of a Spill of Industrial Chemicals—Polychlorinated Biphenyls and Chlorinated Benzenes," National Research Council of Canada, NRCC No. 17586, Ot tawa; 1980. (3) Thomson, Β. Α.; Roberts, J. R. intern. J. Environ. Anal. Chem., in press. (4) Thomson, Β. Α.; Sakuma, T.; Fulford, J.; Lane, D. Α.; Reid, Ν. Μ. Adv. Mass Spectrom. 1980, SB, 1422-1428. (5) Sakuma, T.; Fulford, J.; French, J. B.; Reid, N. M.; Thomson, Β. Α., presented at the 28th Ann. Conf. Mass Spectrom. Allied Top., New York, May 1980. (6) SCI EX, Summary Report prepared for the Ontario Ministry of the Environment, Air Resources Branch; 1980. (7) SCIEX, Report prepared for the Ontario Ministry of the Environment; ARB-TDA Report 05-80. (8) Lane, D. Α.; Thomson, B. A. J. Air Pollul. Control Assoc. 1980, 31(2), 122.
Douglas A. Lane is a senior research sci entist at SCIEX, Inc. His research at SCIEX has involved the development and application of atmospheric pressure chemical ionization mass spectrometric techniques to environmental problems. He was part of the design team that produced the mobile mass spectrometer system de scribed in this article; he subsequently field tested the unit for two and one-half years. He received his B.Sc. in chemistry from the University of Toronto in 1970 and his Ph.D. in analytical chemistry from York University in 1975.
