Supplementary Information

Occurrence of nonylphenol and bisphenol A in household water pipes made of different materials

Y. C. Cheng, H. W. Chen, W. L. Chen, C. Y. Chen and G. S. Wang*

Institute of Environmental Health

National Taiwan University

Taipei, TAIWAN

1 NP and BPA analysis

1.1 sample pretreatments

The sample pretreatment procedures used to extract NP and BPA from water sample have been described previously (Chen et al., 2012), Figure S1 gives the flow chart of the pretreatment processes.

Figure S1 Flow chart of NP and BPA sample pretreatments.

1.2 UPLC analysis

Ultra performance liquid chromatography (UPLC, ACQUITY UPLC system, Waters, Milford, MA, U.S.A.) coupled with Quattro Premier triple quadrapole tandem mass spectrometer (Quattro Premier XE, Waters, MA, U.S.A.) was used to analyze the NP and BPA in water. A Waters BEH C18 UPLC column (2.1 × 100 mm, 1.7 μm) was used to separate the analytes at 60 ℃. The mobile phase was divided into organic phase and water phase which were acetonitrile and 10 mM of N-methylmorpholine individually. 10 μl of sample was injected and eluted off the column at a flow rate of 0.5 ml/min, using a gradient starting from 10％ of acetonitrile in Milli-Q water to 90％ acetonitrile at 3 min and then back to 10％ acetonitrile in 5.5 min. The gradient condition of chromatograph was shown in Table S1.

The analytes were ionized by electrospray ionization (ESI), and set the best spectrometer condition for individual compound to monitor quantifier ions and qualifier ions. According to the chromatographic time, analytes were separated into two regions for better resolution. Table S2 list the precursor ion, product ion, collision energy, cone and dwell time of target compounds.

Table S1 UPLC gradient conditions.

Time (min) / Organic phase (％) / Water phase (％)
0 / 10 / 90
0.2 / 10 / 90
3 / 90 / 10
4 / 90 / 10
5.5 / 10 / 90

Table S2 UPLC spectrometer parameters.

Analyte / Precursor ion (m/z) / First transition (quantifier ion) / Second transition (qualifier ion) / Cone
(V) / Dwell time (s)
Product ion (m/z) / Collision energy (eV) / Product ion (m/z) / Collision energy (eV)
NP / 219.3 / 133.0 / 25 / 147.0 / 30 / 35 / 0.15
4-n-OP
(IS) / 205.2 / 105.8 / 30 / - / - / 35 / 0.005
BPA / 227.0 / 133.0 / 30 / 211.0 / 30 / 40 / 0.04
BPA-D16
(IS) / 241.0 / 142.0 / 30 / - / - / 40 / 0.04

2 Regressions of NP and BPA concentrations in PVC and SS pipes: effects of temperature

Table S3 Results of multiple liner regressions of concentrations of NP and BPA in two types of water (Milli-Q and tap) contained in PVC and stainless steel (SS) pipes: effects of temperature.

Intercept* / Days* / Temp. * / P-value
PVC_NP / Milli-Q / 125.08 / –1.11 / 14.61 / 0.1592
tap / –539.1 / 0.1 / 42.59 / 0.366
PVC_BPA / Milli-Q / 30.9 / –0.07 / 2.03 / 0.744
tap / 53.15 / 0.8 / –6.09 / 0.0463*
SS_NP / Milli-Q / 89.73 / –0.03 / –1.64 / 0.0433*
tap / –26.04 / 0.24 / 2.88 / 0.7156
SS_BPA / Milli-Q / 46.94 / 0.03 / –1.01 / 0.5468
tap / 5.38 / 0.16 / 0.59 / 0.7424

*Significant at P0.05.

Reference:

Chen, W. L., Wang, G. S., Gwo, J. C., Chen, C. Y. (2012). Ultra-high performance liquid chromatography/tandem mass spectrometry determination of feminizing chemicals in river water, sediment and tissue pretreated using disk-type solid-phase extraction and matrix solid-phase dispersion. Talanta, 89(1), 237-245.