1408 Research Article Quantification of heterocyclic amines from thermally processed meats selected from a small-scale population-based study Rosa Busquets, David Mitjans, Lluís Puignou and Maria Teresa Galceran Department of Analytical Chemistry, Chemistry Faculty, University of Barcelona, Barcelona, Spain Heterocyclic amines (HAs) are potent mutagens that form at high temperatures in cooked, protein- rich food. Due to their frequent intake, these compounds are considered a risk factor for human can- cer. Cooking conditions and eating habits strongly influence the level of HA exposure. Thus, it is difficult to assess the intake of HAs in a large population. Food-frequency questionnaires (FFQs), designed to provide data on parameters that affect HA formation, were used to survey a small popula- tion (459 persons) from Barcelona (NE Spain). Subsequently, the most-consumed food items named were cooked according to the preferences of the population surveyed and analyzed for HAs using SPE and LC-MS/MS. In the population studied, the estimated intake via consumption of 13 meat dishes was 285.6 ng of mutagenic HAs per capita and day. PhIP (2-amino-1-methyl-6-phenylimi- dazo[4,5-b]pyridine) was the HA to which the population was most exposed, mainly from fried chicken and griddled beef. When the co-mutagens norharman and harman are included, the mean daily intake of HAs rises to 475.6 ng per capita and day. A novel putative DMIP regioisomer was detected in the cooked meats, which was analyzed in the present study by multistage MS. Keywords: Food mutagens / Heterocyclic amines / Mass spectrometry / Spanish diet / Received: February 4, 2008; revised: May 13, 2008; accepted: May 16, 2008 1 Introduction During the last few decades, different sorts of mutagens have been identified in popular and apparently innocuous food items [1]. Heterocyclic amines (HAs) are a highly mutagenic class of compounds that have been investigated since the detection of mutagenic activity to Salmonella typhimurium TA98 in the smoke produced by broiling fish [2]. HAs are formed from the Maillard reaction, involving creatine, crea- tinine, carbohydrates and free amino acids present in raw protein-rich food [3]. Other sources of exposure to HAs include diesel-exhaust particles [4, 5], tobacco fumes [6] and cooking fumes [7 – 9]. Based on evidences from animal experiments, the International Agency for Research on Can- cer (IARC) classified eight HAs as possible human carcino- gens (class 2B) and 1 as a probable human carcinogen (class 2A) [10]. At present, more than 20 HAs have been character- ized in cooked food and in cooking residues [11]. Further- more, current research on HAs is revealing the presence of novel HAs in cooked food [12 – 15]. Many parameters affect the formation of toxicants in heating processes, which is thus difficult to control. For Correspondence: Professor Lluis Puignou. Department of Analytical Chemistry, Chemistry Faculty, University of Barcelona, c/ Martí Fran- qus 1-11, Barcelona 08028, Spain E-mail: lluis.puignou@ub.edu Fax: +34-93-402-1233 Abbreviations: 4,8-DiMeIQx, 2-amino-3,4,8-trimethylimidazo[4,5- f]quinoline, CAS no. 95896-78-9; 7,8-DiMeIQx, 2-amino-3,7,8-trime- thylimidazo[4,5-f]quinoxaline, CAS no. 92180-79-5; AaC, 2-amino- 9H-pyrido[2,3-b]indole, CAS no. 26148-68-5; D3-PhIP , 2-amino-1-tri- deuteromethyl-6-phenylimidazo[4,5-b]pyridine, CAS no. 210049-13- 1; DMIP , 2-amino-1,6-dimethylimidazo[4,5-b]pyridine, CAS no. 132898-04-5; FFQ, food-frequency questionnaire; Glu-P-1, 2-amino- 6-methyldipyrido[1,2-a:39,29-d]imidazole, CAS no. 67730-11-4; Glu- P-2, 2-aminodipyrido[1,2-a:39,29-d]imidazole, CAS no. 67730-10-3; Harman, 1-amino-9H-pyrido[3,4-b]indole, CAS no. 485-84-0; HA- s, heterocyclic amines; IQ, 2-amino-3-methylimidazo[4,5-f]quinoline, CAS no. 76180-98-6; IARC, International Agency for Research on Cancer; MeAaC, 2-amino-3-methyl-9H-pyrido[2,3-b]indole, CAS no. 68806-83-7; MeIQ, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline, CAS no. 77094-11-2; MeIQx, 2-amino-3,8-dimethylimidazo[4,5- f]quinoxaline, CAS no. 77500-04-0; NCE, Normalized Collision En- ergy; Norharman,9H-pyrido[3,4-b]indole, CAS no. 244-63-3; PhIP , 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, CAS no. 105650-23-5; Trp-P-1, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole, CAS no. 62450-06-0; Trp-P-2, 3-amino-1-methyl-1,4-dimethyl-5H- pyrido[4,3-b]indole, CAS no. 62450-07-1 i 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.mnf-journal.com DOI 10.1002/mnfr.200800048 Mol. Nutr. Food Res. 2008, 52, 1408 – 1420