Multielement Analysis of Soft Drinks by X-ray Fluorescence Spectrometry ORGHE ˆ DA L. A. D. ZUCCHI,* ,² SILVANA MOREIRA, ‡ MARCOS J. SALVADOR, §,| AND LEANDRO L. SANTOS ² Departamento de Fı ´sica e Quı ´mica, Faculdade de Cie ˆncias Farmace ˆuticas de Ribeira ˜o Preto, Universidade de Sa ˜o Paulo, Av. Cafe ´, s/n, CEP 14040-903, Ribeira ˜o Preto-SP, Brasil, Departamento de Recursos Hı ´dricos, Faculdade de Engenharia Civil, Universidade Estadual de Campinas, Caixa Postal 6021, CEP 13083-970, Campinas-SP, Brasil, and Departamento de Quı ´mica, Facultade de Filosofia, Cie ˆncias e Letras de Ribeira ˜o Preto, Universidade de Sa ˜o Paulo, Av. Bandeirantes, 3900, CEP 14040-901, Ribeira ˜o Preto-SP, Brasil Several commercial soft drinks and respective plastic bottles were analyzed for their multielement contents employing the synchrotron radiation total reflection X-ray fluorescence spectrometry technique (SRTXRF). The SRTXRF method has been developed and validated, and about 20 elements were detected in the investigated samples, including some trace elements, which can be toxic for human beings, such as Ti, Cr, Sb, As, and Pb in soft drinks and Al, Sb, As, and Pb in poly(ethylene terephthalate) (PET) containers. Statistical analysis was performed using chemometric techniques (principal component analysis and cluster analysis), and similarities were verified in the multielement contents of the samples. The results demonstrated that the SRTXRF offers a good multielemental approach for the quality control of food products. Moreover, on the basis of enrichment factors, the possibility of the trace elements in the PET container may be leached to the beverages under normal commercial situations and other results were discussed. KEYWORDS: Synchrotron radiation total reflection X-ray fluorescence spectrometry; trace elements; heavy metals; soft drinks; PET bottles; quality control INTRODUCTION Soft drinks are constituted mainly of water, carbon dioxide, and a syrup, whose composition characterizes the beverage flavor. In the mid-1800s, the soft drink forerunner was useful for other purposes: The beverage, made from sparkling water and ginger ale, lemon, or strawberry extracts, was sold in pharm- acies to treat several diseases, from arthritis to indigestion. After 1830, soft drinks had their industrial production initiated (1). In recent years, there has been an increase in consumption, which could be related with the use of poly(ethylene tereph- thalate) (PET) bottles as soft drink containers (2). Thus, because of the high consumption of soft drinks, quality control is particularly important in this case, inasmuch as this kind of food makes up a significant proportion of trace element daily intake (3); furthermore, trace element concentrations are subject to legislation (4). Trace elements in beverages may originate from natural sources, such as soil and water; environmental contamination, including fertilizers and pesticides; industrial processing and containers, such as aluminum cans and, maybe, PET bottles (5, 6). Hence, multielement analysis can be a very valuable tool in the authentication and characterization of beverages as fruit juices (7), teas (8), and alcoholic distillates (9). Moreover, soft drink bottle analyses give information about the polymer additives (allowing to the characterization, constitution, and quality of polymer matrix, indirectly) (10) and trace elements that can be toxic to the human beings (11). Total-reflection X-ray fluorescence (TXRF) is suitable for this kind of work, because of its advantageous features, namely, multielemental capability, high sensitivity and precision, and short time of analysis (12). Other analytical techniques such as atomic absorption spectrometry (AAS), inductively coupled plasma (ICP) atomic emission spectrometry, and neutron activation analysis also can be used for heavy metal determi- nation; however, all need extensive sample preparation, which is usually troublesome and time consuming and prevents in situ analysis (13, 14). In the present paper, the analysis of 17 soft drink samples and the respective PET bottles was carried out by synchrotron radiation TXRF (SRTXRF). The obtained data and its inter- pretation through the statistical tools were used to establish the differences among samples and allowed us to conclude that the technique is feasible for trace element analysis. * To whom correspondence should be addressed. Tel: ++55-16-602- 4244. Fax: ++55-16-633-2960. E-mail: mjsalvador1531@yahoo.com.br or olzucchi@fcfrp.usp.br. ² Departamento de Fı ´sica e Quı ´mica, Universidade de Sa ˜o Paulo. ‡ Universidade Estadual de Campinas. § Departamento de Quı ´mica, Universidade de Sa ˜o Paulo. | Current address: Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi, 2911, 122444-000, Sa ˜o Jose ´ dos Campos, SP, Brasil. J. Agric. Food Chem. 2005, 53, 7863-7869 7863 10.1021/jf0510945 CCC: $30.25 © 2005 American Chemical Society Published on Web 09/10/2005