In Situ Derivatization/Solid-Phase Microextraction: Determination of Polar Aromatic Amines Thomas Zimmermann, Wolfgang J. Ensinger, and Torsten C. Schmidt* Department of Chemistry, Philipps-University Marburg, Hans-Meerwein-Strasse, 35032 Marburg, Germany A solid-phase microextraction GC/ MS method for the trace determination of a wide variety of polar aromatic amines in aqueous samples was developed. Prior to extraction the analytes were derivatized directly in the aqueous solution by diazotation and subsequent iodina- tion in a one-pot reaction. The derivatives were extracted by direct-SPME using a PDMS/ DVB fiber and analyzed by GC/ MS in the full-scan mode. By diazotation/ iodina- tion, the polarity of the analytes was significantly de- creased and as a consequence extraction yields were dramatically improved. The derivatization proved to be suitable for strongly deactivated aromatic amines and even the very polar diamino compounds can efficiently be enriched after derivatization. We investigated 1 8 anilines comprising a wide range of functional groups, which could be determined simultaneously. The method was thor- oughly validated, and the precision at a concentration of 0.5 μg/ L was 3.8 -1 1 % relative standard deviation for nonnitrated analytes using aniline-d 5 as internal standard and 3.7 -1 0 % for nitroaromatic amines without internal standard. The in situ derivatization/ SPME/ GC/ MS method was calibrated over the whole analytical procedure and was linear over 2 orders of magnitude. Using 10-mL samples, detection limits of 2 -13 ng/ L were achieved for 15 of the 18 analytes. For two aminodinitrotoluene isomers and a diaminonitrotoluene, detection limits ranged from 2 7 to 3 8 ng/ L. By allowing quantification at the 0 .1 μg/ L level, analysis of all target compounds meets EU drinking water regulations. The method provides high sensitivity, robustness, and high sample throughput by automation. Finally, the method was applied to various real water samples and in wastewater from a former ammunition plant the contents of several aromatic amines were quantified. Aromatic amines are widespread chemicals in several indus- tries. They are used in the manufacture of rubber chemicals, pesticides, dyes, pharmaceuticals, and photographic chemicals. 1 Their major use, however, is in the production of rigid polyure- thanes and reaction-injection-molded parts for the construction, automotive, and durable goods industries. During production, use, and disposal of these goods, emissions of aromatic amines may occur. Of equal importance is the formation of aromatic amines in the environment due to degradation of precursors, e.g., by microbially mediated reduction of nitroaromatic compounds (NACs). 2,3 NACs are among the most widely used anthropogenic chemicals, and according to the OECD, ∼70 NACs currently are high-production-volume chemicals with a production of more than 1000 t per year in at least one country. Besides contami- nation due to their use, NACs are formed and released during incomplete combustion processes. 4-6 Furthermore, aromatic amines are released during hydrolysis of azo dyes 7 and pesticides. 8 Up to now, more than 30 aromatic amines have been identified in the environment as metabolites of anilides, carbamates, nitro- phenols, or phenylurea pesticides. 8-10 The global annual emis- sion of 4-chloroaniline alonesa compound that has been classified as possibly carcinogenic to humanssis estimated at 1000- 10 000 t. 11 The toxicological properties of arylamines are mainly charac- terized by their ability to form DNA adducts. Currently, the International Agency for Research on Cancer (IARC) has classified six aromatic amines as carcinogenic or probably carcinogenic to humans 12 (IARC list 1 and 2A), but several other anilines also have been found carcinogenic in animal experiments. 13 M any aromatic amines cause damage to DNA and reacted positive in mutagenicity tests. 13 As a consequence, these substances are suspected to be harmful to humans and need to be monitored regularly. * Corresponding author: (phone) + 49-7071-29-7 31 47; (fax) + 49-7071-29- 51 39; (e-mail) torsten.schmidt@ uni-tuebingen.de. Present address: Center for Applied Geosciences, Eberhard-Karls-University Tuebingen, Wilhelmstr. 56, D-72074 Tuebingen. (1) Vogt, P. F.; Geralis, J. J. In Ullmann’s Encyclopedia of Industrial Chemistry, 5 th ed.; Gerhartz, W., Yamamoto, Y. S., Campbell, F. T., Pfefferkorn, R., Rounsaville, J. F., Eds.; VCH: Weinheim, 1985; Vol. A2, p 35. (2) Spain, J. C., Ed. Biodegradation of Nitroaromatic Compounds; Plenum Press: New York, 1995. (3) Larson, R. A.; Weber, E. J. Reaction Mechanisms in Environmental Organic Chemistry; Lewis: Boca Raton, FL, 1994. (4) Gibson, T. L. Mutat. Res. 1983 , 121, 115-121. (5) Tokiwa, H.; Ohnishi, Y. Crit. Rev. Toxicol. 1986 , 17, 23-69. (6) Zwirner-Baier, I.; Neumann, H. G. Mutat. Res. 1999 , 441, 135-144. (7) Clarke, E. A.; Anliker, R. Organic Dyes and Pigments. In Handbook of Environmental Chemistry; Hutzinger, O., Ed.; Springer: Heidelberg, 1980; Vol. 3A. (8) Domsch, K. H. Pestizide im Boden; VCH: Weinheim, 1992. (9) Dorfler, U.; Scheunert, I. Verbleib von Pflanzenchutzmitteln in der Umwelt; Umweltbundesamt: Berlin, 1989. (10) Barcelo, D.; Hennion, M. C. Trace determination of pesticides and their degradation products in water; Elsevier: Amsterdam, 1997. (11) Rippen, G. Handbuch der Umweltchemikalien; Loseblattsammlung, eco- med: Landsberg, 1990. (12) See: http:/ / www.iarc.fr. (13) Gold, L. S.; Zeiger, E. Handbook of carcinogenic potency and genotoxicity databases; CRC Press: Boca Raton, 1997. Anal. Chem. 2004, 76, 1028-1038 1028 Analytical Chemistry, Vol. 76, No. 4, February 15, 2004 10.1021/ac035098p CCC: $27.50 © 2004 American Chemical Society Published on Web 01/15/2004