1.1. Memory and comics
1.1.1. Cultural memory studies
1.1.1.3. Personal memories: narrations of the self
The HS–GC–MS method was applied to determine the eleven LMMAs in genuine drinking water samples that were disinfected with different treatments, namely: chlorination/postchlorination (samples 1–3), chlorination/
postchloramination (samples 4 and 5) and ozonation/postchlorination (samples 6–
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8). Samples were analysed in quintuplicate and the results listed in Table 3. Fig. 4B shows the GC–MS chromatogram (SIM mode) obtained from ozonated water sample 7. EPA Method 556.1 was only applied to determine formaldehyde (C1) in all water samples and acetaldehyde (C2), glyoxal (G) and methylglyoxal (MG) in ozonated water samples because of the low sensitivity of this method (see Table 3, n = 3). As could be expected, aliphatic aldehydes were the compounds present in all types of analysed water, whereas benzaldehyde was the only aromatic aldehyde found. This can be due to the fact that aromatic ones need the presence of large amounts of disinfectants and organic matter for their occurrence; in these water samples the amounts of organic matter and residual chlorine were lower than 2.8 and 0.5 mg/L, respectively. From the results obtained using different disinfection treatments, the concentrations of the eight aldehydes found in ozonated water (samples 6–8) were the highest, with average values of 2.5 µg/L. With respect to treatment by chlorination or chloramination, the average concentrations of the eight LMMAs present were 0.8 and 1.2 µg/L; there is little difference between the two treatments. According to the literature, natural organic matter or pollutants in raw water are oxidised during ozonation, leading to the formation of by-products dominated by organic acids and aldehydes [47].
Due to the lack of sensitivity of EPA Method, a paired t-test was used to compare the results obtained by both methods for C1 in all waters and for C2, G and MG in ozonated waters. No systematic differences were found since the experimental t value was 0.23, being the corresponding t critical value of 2.12 (P = 0.05; df = 16; two-tailed), which corroborates the good performance of the proposed method.
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Table 3 Analysis of drinking water samples treated with different disinfectants by the proposed (HS–GC–MS) and the reference (EPA 556.1) methods (n = 5). Compound Concentration found ± expanded uncertainty (µg/L) Water (chlorination/postchlorination) Water (chlorination/postchloramination)Water (ozonation/postchlorination) 1 2 3 4 5 6 7 8 C12.2 ± 0.3 (1.9 ± 0.4)a1.8 ± 0.3 (2.3 ± 0.5)a1.6 ± 0.3 (2.0 ± 0.4)a2.5 ± 0.4 (2.2 ± 0.5)a3.1 ± 0.5 (2.9 ± 0.6)a4.5 ± 0.8 ( 4.8 ± 1.1)a5.1 ± 0.9 (5.4 ± 1.1) a4.3 ± 0.7 (3.9 ± 0.8)a C21.5 ± 0.3 1.4 ± 0.3 1.3 ± 0.2 1.8 ± 0.3 1.7 ± 0.3 3.8 ± 0.6 ( 3.6 ± 0.8)a3.4 ± 0.6 (3.1 ± 0.6)a3.7 ± 0.6 (4.0 ± 0.9)a C31.0 ± 0.2 0.8 ± 0.2 1.1 ± 0.2 1.4 ± 0.3 1.2 ± 0.2 2.2 ± 0.4 2.1 ± 0.3 1.9 ± 0.3 C40.9 ± 0.2 1.0 ± 0.2 0.8 ± 0.1 1.2 ± 0.2 1.5 ± 0.3 2.0 ± 0.3 1.6 ± 0.3 2.0 ± 0.3 C50.42 ± 0.080.54 ± 0.090.41 ± 0.080.8 ± 0.2 0.7 ± 0.1 1.6 ± 0.3 1.5 ± 0.3 1.3 ± 0.2 G0.07 ± 0.020.11 ± 0.020.08 ± 0.020.34 ± 0.070.21 ± 0.044.0 ± 0.7 (3.6 ± 0.8)a3.2 ± 0.6 (3.5 ± 0.8)a3.7 ± 0.7 (3.5 ± 0.8)a MG0.13 ± 0.020.31 ± 0.050.33 ± 0.060.52 ± 0.090.44 ± 0.081.2 ± 0.2 (1.5 ± 0.4)a1.5 ± 0.3 (1.2 ± 0.3)a1.3 ± 0.2 (1.7 ± 0.4)a BA0.34 ± 0.070.5 ± 0.1 0.43 ± 0.081.0 ± 0.2 0.7 ± 0.2 1.4 ± 0.3 1.2 ± 0.3 1.1 ± 0.3 3–MBAn.d.bn.d.n.d.n.d.n.d.n.d.n.d.n.d. 2–EBAn.d.n.d.n.d.n.d.n.d.n.d.n.d.n.d. 2,5–DMBAn.d.n.d.n.d.n.d.n.d.n.d.n.d.n.d. a values provided by EPA Method 556.1( n = 3). b n.d., not detected.
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4. Conclusions
The high volatility of fluorine-rich PFBHA-oxime derivatives enables the use of the static headspace technique with an efficiency of the whole analytical process which ranges from 80% (dicarbonyl aldehydes) to 95% (aliphatic aldehydes). The analysis of the data obtained from the proposed HS–GC–MS method led to the following conclusions: (i) for the first time, LMMAs derivatisation reaction with PFBHA is carried out in an alkaline medium (pH 8.4) by using sodium hydrogen carbonate, which also acts as a salting-out agent; (ii) the hydrogen carbonate ion exerts a positive significant effect on the derivatisation efficiency of the target aldehydes. Enhancement factors up to 20-fold can be achieved for aromatic LMMAs with respect to those obtained when derivatisation was carried out in a weak acid medium (pH 4.0) as recommended in EPA Method 556.1 [32]; and (iii) the addition of n-hexane aliquots favoured the volatilisation of all oximes; signals were increased between 30% and 50% in relation to those obtained without a modifier. It is expected that this approach could greatly simplify the determination of aldehydes in various types of water.
Acknowledgements
This work was funded in the frameworks of Projects CTQ2010-17008 (Spain’s Ministry of Education) and P09-FQM-4732 (Andalusian Regional Government). FEDER provided additional funding. María Serrano is grateful for the award of a pre-doctoral grant from Project CTQ2010-17008.
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References
[1] S.D. Richardson, M.J. Plewa, E.D. Wagner, R. Schoeny, D.M. DeMarini, Occurrence, genotoxicity, and carcinogenicity of regulated and emerging disinfection by-products in drinking water: a review and roadmap for research, Mutat. Res. 636 (2007) 178–242.
[2] D. Cutler, G. Miller, The role of public health improvements in health advances: the new twentieth-century United State, Demography 42 (2005) 1–22.
[3] G. Hua, D.A. Reckhow, Comparison of disinfection byproduct formation from chlorine and alternative disinfectants, Water Res. 41 (2007) 1667–1678.
[4] C. Blasco, Y. Picó, Prospects for combining chemical and biological methods for integrated environmental assessment, TrAC, Trends Anal.
Chem. 28 (2009) 745–757.
[5] S.D. Richardson, in: J.O. Nriagu (Ed.), Disinfection By-products: Formation and Occurrence in Drinking Water, Elsevier Science Inc., Massachusetts, 2011, pp. 110–136.
[6] S.D. Richardson, Environmental mass spectrometry: Emerging contaminants and current issues, Anal. Chem. 84 (2012) 747–778.
[7] S.D. Richardson, The role of GC-MS and LC-MS in the discovery of drinking water disinfection by-products, J. Environ. Monit. 4 (2002) 1–9.
[8] S.D. Richardson, A.D. Thruston Jr., T.V. Caughran, P.H. Chen, T.W.
Collette, K.M. Schenck, B.W. Lykins Jr., C. Rav-Acha, V. Glezer, Identification of new drinking water disinfection by-products from ozone, chlorine dioxide, chloramine, and chlorine, Water Air Soil Pollut. 123 (2000) 95–102.
[9] S.D. Richardson, A.D. Thruston Jr., T.V. Caughran, P.H. Chen, T.W.
Collette, T.L. Floyd, K.M. Schenck, B.W. Lykins Jr., G. Sun, G. Majetich, Identification of new ozone disinfection byproducts in drinking water, Environ. Sci. Technol. 33 (1999) 3368–3377.
132
[10] A. Hebert, D. Forestier, D. Lenes, D. Benanou, S. Jacob, C. Arfi, L.
Lambolez, Y. Levi, Innovative method for prioritizing emerging disinfection by-products (DBPs) in drinking water on the basis of their potential impact on public health, Water Res. 44 (2010) 3147–3165.
[11] M.J. Nieuwenhuijsen, R. Smith, S. Golfinopoulos, N. Best, J. Bennett, G.
Aggazzotti, E. Righi, G. Fantuzzi, L. Bucchini, S. Cordier, C.M. Villanueva, V. Moreno, C. La Vecchia, C. Bosetti, T. Vartiainen, R. Rautiu, M.
Toledano, N. Iszatt, R. Grazuleviciene, M. Kogevinas, Health impacts of long-term exposure to disinfection by-products in drinking water in Europe:
HIWATE, J. Water Health 7 (2009) 185–207.
[12] Y.T. Woo, D. Lai, J.L. McLain, M.K. Manibusan, V. Dellarco, Use of mechanism-based structure–activity relationships analysis in carcinogenic potential ranking for drinking water disinfection by-products, Environ.
Health Perspect. 110 (2002) 75–87.
[13] World Health Organisation, Guideline for Drinking-water Quality. First to Addendum to Third Edition, vol. 1: Recommendations, 2006, http://www.who.int/water sanitation health/dwq/gdwq0506.pdf (accessed 20.05.13).
[14] J.M. Fernández-Molina, M. Silva, Trace determination of low-molecular-mass substituted benzaldehydes in treated water using micro solid-phase extraction followed by liquid chromatography–mass spectrometric detection, J. Chromatogr. A 1300 (2013) 180–186.
[15] J.M. Fernández-Molina, M. Silva, Improved solid-phase extraction/micellar procedure for the derivatization/preconcentration of benzaldehyde and methyl derivatives from water samples, Talanta 85 (2011) 449–454.
[16] J.M. Fernández-Molina, M. Silva, Simple and sensitive determination of low-molecular-mass aromatic aldehydes in swimming pool water by LC-diode array detector, J. Sep. Sci. 34 (2011) 2732–2738.
[17] A.K.K.V. Pillai, K. Gautam, A. Jain, K.K. Verma, Headspace in-drop derivatization of carbonyl compounds for their analysis by
high-133 performance liquid chromatography-diode array detection, Anal. Chim. Acta 632 (2009) 208–215.
[18] C.E. Baños, M. Silva, Comparison of several sorbents for continuous in situ derivatization and preconcentration of low-molecular mass aldehydes prior to liquid chromatography–tandem mass spectrometric determination in water samples, J. Chromatogr. A 1216 (2009) 6554–6559.
[19] K. Takeda, S. Katoh, N. Nakatani, H. Sakugawa, Rapid and highly sensitive determination of low-molecular-weight carbonyl compounds in drinking water and natural water by preconcentration HPLC with 2,4-dinitrophenylhydrazine, Anal. Sci. 22 (2006) 1509–1514.
[20] C. Zwiener, T. Glauner, F.H. Frimmel, Method optimization for the determination of carbonyl compounds in disinfected water by DNPH derivatization and LC–ESI–MS–MS, Anal. Bioanal. Chem. 372 (2002) 615–
621.
[21] M. Serrano, M. Silva, M. Gallego, Development of an environment-friendly microextraction method for the determination of aliphatic and aromatic aldehydes in water, Anal. Chim. Acta 784 (2013) 77–84.
[22] Q. Ye, D. Zheng, L. Liu, L. Hong, Rapid analysis of aldehydes by simultaneous microextraction and derivatization followed by GC-MS, J. Sep.
Sci. 34 (2011) 1607–1612.
[23] J. Beránek, A. Kubátová, Evaluation of solid-phase microextraction methods for determination of trace concentration aldehydes in aqueous solution, J. Chromatogr. A 1209 (2008) 44–54.
[24] H.G. Schmarr, T. Potouridis, S. Ganß, W. Sang, B. Köpp, U. Bokuz, U.
Fischer, Analysis of carbonyl compounds via headspace solid-phase microextraction with on-fiber derivatization and gas chromatographic–ion trap tandem mass spectrometric determination of their o-(2,3,4,5,6-pentafluorobenzyl)oxime derivatives, Anal. Chim. Acta 617 (2008) 119–131.
[25] V. Ferreira, L. Culleré, N. Loscos, J. Cacho, Critical aspects of the determination of pentafluorobenzyl derivatives of aldehydes by gas
134
chromatography with electron-capture or mass spectrometric detection.
Validation of an optimized strategy for the determination of oxygen-related odor-active aldehydes in wine, J. Chromatogr. A 1122 (2006) 255–265.
[26] C. Deng, N. Yao, N. Li, X. Zhang, Headspace single-drop microextraction with in-drop derivatization for aldehyde analysis, J. Sep. Sci. 28 (2005) 2301–
2305.
[27] T. Gabrio, A. Bertsch, Determination of carbonyl compounds in pool water with o-(2,3,4,5,6-pentafluorobenzyl) hydroxyamine hydrochloride and gas chromatographic–tandem mass spectrometric analysis, J. Chromatogr. A 1046 (2004) 293–296.
[28] S.W. Tsai, C.M. Chang, Analysis of aldehydes in water by solid-phase microextraction with on-fiber derivatization, J. Chromatogr. A 1015 (2003) 143–150.
[29] N. Sugaya, T. Nakagawa, K. Sakurai, M. Morita, S. Onodera, Analysis of aldehydes in water by head space-GC/MS, J. Health Sci. 47 (2001) 21–27.
[30] B. Cancho, F. Ventura, M.T. Galceran, Determination of aldehydes in drinking water using pentafluorobenzylhydroxylamine derivatization and solid-phase microextraction, J. Chromatogr. A 943 (2001) 1–13.
[31] J. Beránek, D.A. Muggli, A. Kubátová, Detection limits of electron and electron capture negative ionization-mass spectrometry for aldehydes derivatized with o-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine hydrochloride, J. Am. Soc. Mass Spectrom. 21 (2010) 592–602.
[32] US EPA, Methods for the Determination of Carbonyl Compounds in Drinking Water by Fast Gas Chromatography Revision 1.0, National Exposure Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Cincinnati, OH, 1999.
[33] US EPA, Methods for the Determination of Carbonyl Compounds by High Performance Liquid Chromatography Revision 1.0, SW-846 Ch 4.3.3, National Exposure Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Cincinnati, OH, 1996.
135 [34] P.T. Anastas, Green chemistry and the role of analytical methodology
development, Crit. Rev. Anal. Chem. 29 (1999) 167–175.
[35] A. Galuszka, Z. Migaszewski, J. Namiesnik, The 12 principles of green analytical chemistry and the SIGNIFICANCE mnemonic of green analytical practices, TrAC, Trends Anal. Chem. 50 (2013) 78–84.
[36] E. Psillakis, N. Kalogerakis, Developments in single-drop microextraction, TrAC, Trends Anal. Chem. 21 (2002) 53–63.
[37] W.P. Jencks, Studies on the mechanism of oxime and semicarbazone formation, J. Am. Chem. Soc. 81 (1959) 475–481.
[38] S. Dayagi, Y. Degani, in: S. Patai (Ed.), The Chemistry of Carbon–Nitrogen Double Bond, Interscience, United Kingdom, 1970, pp. 69–71.
[39] G.L. Kad, M. Bhandari, J. Kaur, R. Rathee, J. Singh, Solventless preparation of oximes in the solid state and via microwave irradiation, Green Chem. 3 (2001) 275–277.
[40] U.P. Lad, M.A. Kulkarni, R.S. Patil, Synthesis of oximes in aqueous medium using hyamine as an eco-friendly catalyst at ambient temperature, Rasayan J.
Chem. 3 (2010) 425–428.
[41] S. Salahuddin, O. Renaudet, J.L. Reymond, Aldehyde detection by chromogenic/fluorogenic oxime bond fragmentation, Org. Biomol. Chem.
2 (2004) 1471–1475.
[42] S.K. Dewan, R. Singh, A. Kumar, One pot synthesis of nitriles from aldehydes and hydroxylamine hydrochloride using sodium sulphate (anhyd) and sodium bicarbonate in dry media under microwave irradiation, Arkivoc 2 (2006) 41–44.
[43] L.O. Krbechek, US Patent 5488161 A 19960130 (1996).
[44] M.J. Cardador, A. Serrano, M. Gallego, Simultaneous liquid–liquid microextraction/methylation for the determination of haloacetic acids in drinking waters by headspace gas chromatography, J. Chromatogr. A 1209 (2008) 61–69.
136
[45] N.J. Miller, J.C. Miller, Statistics and Chemometrics for Analytical Chemistry, 5th ed., Prentice Hall, New Jersey, 2005.
[46] S.L.R. Ellison, A. Williams, EURACHEM/CITAC guide: Quantifying Uncertainty in Analytical Measurement, 3rd ed., 2012, Available from http://www.eurachem.org
[47] S. Peldszus, in: L.M.L. Nollet (Ed.), Chromatographic Analysis of the Environment, CRC Press, Taylor & Francis Group, Florida, 2006, pp. 453–
511.