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Determination of endocrine-disrupting compounds in water by gas
chromatography with mass spectrometric detection
S. Rocha 1 , C. Pinho 1 , V.F. Domingues 2 , C. Mansilha 3,4 , P. Gameiro 1
1 REQUIMTE, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
2 REQUIMTE, Instituto Superior de Engenharia do Porto, Porto, Portugal
3 Instituto Nacional de Saúde Doutor Ricardo Jorge, Porto, Portugal
4 REQUIMTE, Universidade do Porto, Portugal
Chemical compounds such as bisphenol-A (BPA), estrone (E1), 17β-estradiol (E2) and 17βethinylestradiol
(EE2) are classified as “endocrine-disrupting compounds” (EDCs), that were
defined by the European Commission as “exogenous substances that cause adverse health
effects in an intact organism, or its progeny, consequent to changes in endocrine function” [1] .
The natural estrogens such as E1 and E2 are mainly derived from excreta of humans and
livestock. EE2 is a synthetic steroid and is the most common used as contraceptive and in
hormonal therapies. Environmental waters contamination is due to large volumes of municipal,
agricultural and industrial wastewater discharges. Apart from these steroids, BPA have been
mainly used for the production of epoxy resins and polycarbonates and it is also considered a
compound with estrogenic activity, with impact in environment and an incipient of concern in
bottled waters [2] .
The main objective of this work was to implement and validate a sensitive and selective
methodology to detect and quantify 4 EDCs, simultaneously, in environmental water samples
and bottled waters (analysis of BPA) using solid-phase extraction (SPE) and Gas
Chromatography tandem Mass Spectrometry (GC-MS), after derivatization with silylation
agent N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) [2] . The GC-MS determinations
were performed in parallel on a Thermo Polaris Q with an ion trap mass spectrophotometer and
a temperature-programmable injector (PTV) and on a Shimadzu GCMS-QP2010 Plus with a
single quadrupole mass spectrophotometer in injection splitless mode. Linear calibration
curves were obtained to the EDCs for concentrations ranging from 50 to 500 µg.L -1 .
The SPE optimization was done using different cartridges such as Grace Pure Fast, Grace Pure
Low, Strata TM -X, Strata TM SDB-L, LiChrolut ® RP-18 and LiChrolut ® EN/RP-18. All analytical
calibration curves, from direct injection of standard mixtures showed a coefficient correlation
level (R) higher than 0.996. Instrumental quantification limits for BPA, E1, E2 and EE2 were
54.4, 42.6, 50.1 and 91.9 μg.L -1 for Thermo Polaris Q and 62.8, 117.6, 180.0 and 68.0 μg.L -1
for Shimadzu GCMS-QP2010 Plus, respectively. SPE methodology shows recovery above
90% for all cartridges tested. The results suggest that with a single step of sample preparation it
is possible to achieve good recoveries for these four EDCs, allowing the analysis of different
water matrices.
References:
[1] Jeannot, R., Sabik, H., Sauvard, E., Dagnac, T. and Dohrendorf, K. (2002), Determination of
endocrine-disrupting compounds in environmental samples using gas and liquid chromatography with
mass spectrometry, Journal of Chromatography A, 974, 143-159.
[2] Quintana, J.B., Carpinteiro J., Rodriguez, I., Lorenzo, R.A., Carro, A.M. and Cela, R. (2004),
Determination of natural and synthetic estrogens in water by gas chromatography with mass
spectrometric detection, Journal of Chromatography A, 1024, 177-185.
252 3 rd meeting of young researchers at UP