Identification and quantification of chlorinated bisphenol A in wastewater from wastepaper recycling plants

Article abstract of DOI:10.1016/S0045-6535(00)00507-5

Chlorinated derivatives of bisphenol A were detected in the final effluents of eight paper manufacturing plants in Shizuoka, Japan, where thermal paper and/or other printed paper is used as the raw material. Their amounts were determined by gas chromatography/mass spectrometry (GC/MS) after treatment with N, O-bis(trimethylsilyl) trifluoroacetamide, and ranged from traces to 2.0 μg/1. They are likely produced by chlorination of bisphenol A, which was released into the effluents from the pulping process of wastepaper, during or after bleaching with chlorine.

Full text of DOI:10.1016/S0045-6535(00)00507-5

Chemosphere 44 02001) 973±979
www.elsevier.com/locate/chemosphere
Identi®cation and quanti®cation of chlorinated bisphenol A in
wastewater from wastepaper recycling plants
a
a
Hitoshi Fukazawa a,b, Kentaro Hoshino , Tatsushi Shiozawa ,
b
Hidetsuru Matsushita , Yoshiyasu Terao
a,
*
a
Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
b
Shizuoka Institute of Environment and Hygiene, 4-27-2 Kitaando, Shizuoka 420-8637, Japan
Received 23 June 2000; accepted 5 September 2000
Abstract
Chlorinated derivatives of bisphenol A were detected in the ®nal e‚uents of eight paper manufacturing plants in
Shizuoka, Japan, where thermal paper and/or other printed paper is used as the raw material. Their amounts were
determined by gas chromatography/mass spectrometry 0GC/MS) after treatment with N, O-bis0trimethylsilyl)tri¯uo-
roacetamide, and ranged from traces to 2:0 lg=l. They are likely produced by chlorination of bisphenol A, which was
released into the e‚uents from the pulping process of wastepaper, during or after bleaching with chlorine. Ó 2001
Elsevier Science Ltd. All rights reserved.
Keywords: Bisphenol A; Sodium hypochlorite; Wastepaper recycling; GC/MS
1. Introduction
factories as well as a disinfection agent in sewage treat-
ment plants. Thus it is important to investigate the re-
lease of chlorinated bisphenol A into the environment
and its toxicity.
Bisphenol A 0BPA), 2,2-bis04-hydroxyphenyl)pro-
pane has been reported to interact with estrogen recep-
tors, suggesting that it may serve as endocrine disrupter
at environmental concentrations below acute toxic levels
0Alexander et al., 1988; Olea et al., 1996; Routledge and
Sumpter, 1996; Coldham et al., 1997; Steinmetz et al.,
1997). Bisphenol A is a common raw material used in
the polymer and plastics industries, and is also used to
produce paper, such as thermal paper and carbonless
copy paper. Therefore, many factories that recycle
wastepaper are thought to release bisphenol A into
wastewater.
There are more than 100 wastepaper recycling plants
in Shizuoka prefecture, Japan. If these plants incorpo-
rate a chlorine-bleaching process, chlorinated bisphenol
A may be produced and released into the wastewater. In
the present study, we have quantitatively analyzed the
chlorinated bisphenol A released from the wastepaper
recycling process.
2. Experimental
Bisphenol A is easily chlorinated by sodium hypo-
chlorite, which is used as a bleaching agent in paper
2.1. Materials and spectral measurement
Bisphenol A and bisphenol A-d16 were purchased
from Kanto Chemical, Japan. N,O-Bis0trimethylsi-
lyl)tri¯uoroacetamide 0BSTFA) 0GC grade) was ob-
tained from Wako Pure Chemicals Industry, Japan. All
* Corresponding author. Tel.: +81-54-264-5788; fax: +81-54-
264-5788.
E-mail address: terao@u-shizuoka-ken.ac.jp 0Y. Terao).
0045-6535/01/$ - see front matter Ó 2001 Elsevier Science Ltd. All rights reserved.
PII: S0 0 4 5 - 6 5 3 5 0 0 0 ) 0 0 5 0 7 - 5

974
H. Fukazawa et al. / Chemosphere 44 /2001) 973±979
solvents used were of pesticide analysis grade. Water
was treated by a Milli-Q Water Puri®cation System after
distillation and then puri®ed by an activated carbon
d, J ˆ 8:8 Hz, 2  ArH), 7.00 02H, dd, J ˆ 2:3, 8.8 Hz,
2  ArH), 7.16 02H, d, J ˆ 2:3 Hz, 2  ArH).
2-03-Chloro-4-hydroxyphenyl)-2-03,5-dichloro-4-hy-
droxyphenyl)propane 03,30,5-triClBPA); 2.3 g 012%), mp
74±75°C. HRMS m=z: 329.9974 0calcd for C15H13Cl3O2,
1
column. H-NMR and 13C-NMR spectra were taken of
solutions in chloroform-d with a JEOL JNM-GSX270
1H: 270 MHz, 13C: 67.5 MHz) or a JNM-GSX500 01H:
500 MHz , 13C: 125 MHz) Fourier-transform spec-
trometer. The following abbreviations are used: s ˆ
singlet, d ˆ doublet, t ˆ triplet, q ˆ quartet and br ˆ
broad. Chemical shifts are shown in ppm using tetra-
methylsilane as an internal standard. High-resolution
mass spectra were measured using a JEOL JMS-DX300
or a JEOL JMS-AX505w mass spectrometer.
1
329.9981). H-NMR 0CDCl3) d: 1.59 06H, s, 2 Â CH3),
5.51 01H, br, OH), 5.79 01H, br, OH), 6.93 01H, d,
J ˆ 8:5 Hz, ArH), 6.98 01H, dd, J ˆ 2:3, 8.5 Hz, ArH),
7.08 02H, s, 2  ArH), 7.16 01H, d, J ˆ 2:3 Hz, ArH).
2,2-Bis03,5-dichloro-4-hydroxyphenyl)propane 03,30,5,50-
tetraClBPA); 0.67 g 03%), mp 135±136°C. HRMS m=z:
363.9615 0calcd for C15H12Cl4O2, 363.9594). 1H-NMR
0CDCl3) d: 1.59 06H, s, 2 Â CH3), 5.78 02H, br, 2 Â OH),
7.07 04H, s, 4 Â ArH).
2.2. Synthesis of chlorinated bisphenol A
2.3. Synthesis of 2-/3,5-dichloro-4-hydroxyphenyl)-2-/4-
hydroxyphenyl) propane /3,5-diClBPA)
Sodium hypochlorite solution 0100 ml, available
chlorine >5%) was added dropwise to a stirred solution
of bisphenol A 013.7 g, 60 mmol) in methanol 0100 ml) at
room temperature, and the stirring was continued for
11 h. After adding 1 M-sodium sul®te solution 050 ml),
the mixture was condensed under reduced pressure to
one-half of the initial volume, acidi®ed with 10% hy-
drochloric acid and extracted with dichloromethane. The
organic layer was washed with brine, dried over anhy-
drous magnesium sulfate and evaporated to dryness. An
oily residue was subjected to chromatography on a silica
gel column 0eluent: chloroform and 1% methanol in
chloroform) to give the following crystalline products:
2-03-Chloro-4-hydroxyphenyl)-2-04-hydroxyphenyl)
propane 03-ClBPA); 4.9 g 031%), mp 111±112°C. HRMS
m=z: 262.0801 0calcd for C15H15ClO2, 262.0761).
1H-NMR 0CDCl3) d: 1.60 06H, s, 2 Â CH3), 5.24 01H,
br, OH), 5.54 01H, br, OH), 6.73 02H, dt, J ˆ 2:6, 8.9
Hz, 2  ArH), 6.89 01H, d, J ˆ 8:4 Hz, ArH), 7.00 01H,
dd, J ˆ 2:4, 8.4 Hz, ArH), 7.07 02H, dt, J ˆ 2:6, 8.9 Hz,
2  ArH), 7.17 01H, d, J ˆ 2:4 Hz, ArH).
A solution of pivaloyl chloride 011.1 ml, 90 mmol) in
dichloromethane 020 ml) was added to a stirred solution
of bisphenol A 013.7 g, 60 mmol) and triethylamine 018.2
ml, 130 mmol) in dichloromethane 0100 ml) at room
temperature. After stirring for 15 h, cold water was
added and the organic layer was separated, washed with
brine and dried over anhydrous magnesium sulfate.
Removal of the solvent under reduced pressure gave a
solid residue, which was subjected to chromatography
on a silica gel column 0eluent: 10% ethyl acetate in
hexane) to give crystals of 2-04-hydroxyphenyl)-2-04-
pivaloyloxyphenyl)propane 0BPA-monopivalate); 16.8 g
090%), mp 138±139°C. 1H-NMR 0CDCl3) d: 1.20 09H, s,
3 Â CH3), 1.50 06H, s, 2 Â CH3), 4.61 01H, br OH), 6.58
02H, dt, J ˆ 2:1, 8.7 Hz, 2  ArH), 6.81 02H, dt, J ˆ 2:1,
8.7 Hz, 2  ArH), 6.94 02H, dt, J ˆ 2:2, 8.8 Hz,
2  ArH), 7.07 02H, dt, J ˆ 2:2, 8.8 Hz, 2  ArH). So-
dium hypochlorite solution 035 ml, available chlorine
>0.05%) was added dropwise to a stirred solution of
BPA-monopivalate 015.2 g, 50 mmol) in methanol 0100
ml). After stirring for an additional hour, the reaction
was quenched by adding 1 M-sodium sul®te solution 020
ml). The reaction mixture was condensed under reduced
2,2-Bis03-chloro-4-hydroxyphenyl)propane 03,30-diC-
lBPA); 4.1 g 023%), mp 90±92°C. HRMS m=z: 296.0345
1
0calcd for C15H14Cl2O2, 296.0372) H-NMR 0CDCl3) d:
1.60 06H, s, 2 Â CH3), 5.47 02H, br, 2 Â OH), 6.91 02H,
Fig. 1. Chemical structures of bisphenol A and the chlorinated derivatives.

H. Fukazawa et al. / Chemosphere 44 /2001) 973±979
975
pressure to give an oily residue, which was extracted
with dichloromethane. The organic layer was washed
with brine and dried over anhydrous magnesium sulfate.
After removal of the solvent, the residue was subjected
to chromatography on a silica gel column 0eluent: 10%
of ethyl acetate in hexane) to give crystals of 2-03,5-di-
chloro-4-hydroxyphenyl)-2-04-pivaloyloxyphenyl)pro-
pane 03,5-diClBPA-monopivalate); 6.5 g 034%), mp 148±
149°C. 1H-NMR 0CDCl3) d: 1.23 09H, s, 3 Â CH3), 1.50
06H, s, 2 Â CH3), 5.82 01H, br, OH), 6.86 02H, dt,
J ˆ 2:2, 8.8 Hz, 2  ArH), 6.98 02H, s, 2  ArH), 7.07
02H, dt, J ˆ 2:2, 8.8 Hz, 2  ArH). To a solution of 3,
5-diClBPA-monopivalate described above 01.9 g, 10
mmol) in methanol 020 ml) a 10% aqueous solution of
potassium carbonate 020 ml) was added. The mixture
was stirred at room temperature for 2 h, and the
methanol was then evaporated under reduced pressure
to give an aqueous residue, which was acidi®ed with 10%
hydrochloric acid and extracted with dichloromethane.
The organic layer was washed with brine and dried over
Fig. 2. Mass spectra of bis0trimethylsilyl) ethers of BPA 01), 3-ClBPA 02), 3,5-diClBPA 03), 3,30-diClBPA 04), 3,30,5-triClBPA 05),
3,30,5,50-tetraClBPA 06).

976
H. Fukazawa et al. / Chemosphere 44 /2001) 973±979
anhydrous magnesium sulfate. Removal of the solvent
under reduced pressure gave a solid which was recrys-
tallized from hexane to give pure 3,5-diClBPA, 1.6 g
055%); mp 110±112°C. HRMS m=z: 296.0403 0calcd for
C15H14Cl2O2, 296.0372). 1H-NMR 0CDCl3) d: 1.60 06H,
s, 2 Â CH3), 4.95 01H, br, OH), 5.75 01H, br, OH), 6.75
02H, dt, J ˆ 2:2, 8.7 Hz, 2  ArH), 7.06 02H, dt, J ˆ 2:2,
8.7 Hz, 2 Â ArH), 7.09 02H, s, 2 Â ArH).
dried over anhydrous sodium sulfate and treated in the
same way as described above.
2.7. Biodegradation of bisphenol A and chlorinated
bisphenol A
In a 5-l glass ¯ask covered with aluminum foil, 2 l of
supernatant of activated sludge were diluted with the
same volume of pure water. The aqueous solution was
stirred slowly with a magnetic stirrer for 24 h. To the
solution an acetone solution containing 16 lg of bi-
sphenol A, 3-ClBPA, 3,30-diClBPA, 3,30,5-triClBPA and
3,30,5,50-tetraClBPA was added. After stirring for 30
min, two 100 ml samples were taken and immediately
extracted twice with 20 ml of dichloromethane. Each
extract was subjected to GC/MSanalysis as described
above. Samples taken after 1, 2, 3, 5 and 7 days of
stirring were treated as described above. The tempera-
ture was kept at 24±26°C during the test.
2.4. GC/MS apparatus and operating conditions
Gas chromatography/mass spectrometry 0GC/MS):
Hewlett Packard HP-5890 II gas chromatograph and
Hewlett Packard HP-5971A mass spectrometer. The
GC/MSconditions were as follows: column, HP-5 trace
analysis 05% diphenyl and 95% dimethylarylenesiloxane,
coating ®lm thickness 0:1 lm, 0:25 mm i:d: Â 30 m,
Hewlett Packard); injection mode, splitless; injection
temperature, 250°; column head pressure, 7 psi; column
temperature, 100±270°; program rate, 15°/min; ionizing
voltage, 70 eV. MSmeasurement was performed in scan
mode for a qualitative analysis and in the selected ion
monitoring 0SIM) mode for a quantitative analysis. The
chlorinated derivatives of bisphenol A were detected
after trimethylsilylation with BSTFA, and the ions
monitored were BPA, m=z 357, 372, 207; 3-ClBPA, m=z
392, 393, 406; 3,30- and 3,5-diClBPA, m=z 425, 427, 440;
3,30,5-triClBPA, m=z 459, 461, 474; 3,30,5,50-tetraClBPA,
m=z 493, 495, 510.
3. Results and discussion
3.1. Synthesis and structural determination of chlorinated
bisphenol A
Treatment of bisphenol A with an excess of sodium
hypochlorite gave mono-, di-, tri- and tetra-chlorinated
2.5. Detection of chlorinated bisphenol A formed by the
reaction with sodium hypochlorite in aqueous medium
An acetone solution of 20 lg of bisphenol A was
added to 20 ml of sodium hypochlorite solution 010 mg/l
of chlorine) adjusted to pH 11 with sodium hydroxide
solution. The solution was allowed to stand with occa-
sional shaking for an appropriate time at room tem-
perature. After adding 0.01 M-sodium thiosulfate
solution, the reaction mixture was acidi®ed with hy-
drochloric acid 0pH 4), and then extracted twice with 2
ml of dichloromethane. The dichloromethane solution
was dried over anhydrous sodium sulfate and concen-
trated on a rotary evaporator to about 1 ml, and ®nally
to 0.3 ml under a nitrogen stream. After adding 200 ll
of BSTFA solution, the solution was allowed to stand
for 30 min to complete the trimethylsilylation. The re-
action solution was concentrated again to 0.3 ml under a
nitrogen stream, diluted up to 1 ml with dichlorome-
thane and subjected to GC/MS0SIM) analysis.
2.6. Sample preparation
A water sample 0100 ml) was acidi®ed with hydro-
chloric acid 0pH 4) and extracted twice with 20 ml of
dichloromethane. The dichloromethane solution was
Fig. 3. Fragmentation of bis0trimethylsilyl) ethers of bisphenol
A and the chlorinated derivatives.

H. Fukazawa et al. / Chemosphere 44 /2001) 973±979
977
bisphenol A, which were separated by chromatographic
methods. Since 3,5-diClBPA was scarcely produced by
this reaction, it was synthesized via 2-04-hydroxyphe-
nyl)-2-04-pivaloyloxyphenyl)propane. Their structures
were determined on the basis of their high-resolution
3.2. Mass spectrometric fragmentation patterns of chlo-
rinated bisphenol A
Mass spectra of bis0trimethylsilyl) ethers of bisphenol
A and chlorinated bisphenol A are shown in Fig. 2. The
‡
1
mass and H-NMR spectra. Fig. 1 shows the chemical
structures of the chlorinated derivatives of bisphenol A
obtained.
molecular ion peaks 0M ) in the mass spectra of these
compounds are very small. However, the intense
‡
0M ±CH3) peaks can be used without diculty to
Fig. 4. Total ion chromatograms 0TIC) of the solution of bis0trimethylsilyl) ethers of bisphenol A and chlorinated derivatives: 0a) the
standard solution, 0b) the sample taken after the reaction of bisphenol A with NaClO for 5 min, and 0c) for 60 min, 0c0) expansion of
0c), 0d) the sample in plant 3. Peak number: 1 ˆ BPA, 2 ˆ 3-ClBPA, 3 ˆ 3,5-diClBPA, 4 ˆ 3,30-diClBPA, 5 ˆ 3,30,5-triClBPA, 6 ˆ
3,30,5,50-tetraClBPA.

978
H. Fukazawa et al. / Chemosphere 44 /2001) 973±979
Table 1
Concentrationa of BPA and chlorinated derivatives in ®nal e‚uents from paper recycling plants
Plant no.
BPA
3-Cl BPA
3,5-diCl BPA
0.4
3,30-diCl BPA
Trace
3,30,5-triCl BPA
3,30,5,50-tetraCl BPA
1
2
3
4
5
6
7
8
8
41
0.3
Trace
0.8
0.5
43
63
1.0
0.4
Trace
0.5
1.2
0.9
1.4
1.3
119
195
202
370
2.0
0.2
Trace
Trace
0.3
a lg=l, trace: <0:2 lg=l.
determine the molecular weights. The loss of a methyl
group was demonstrated to originate from the propyl
moiety on the basis of the spectrum of bis0trimethylsilyl)
lBPA and 3,30,5,50-tetraClBPA were observed in the TIC
of the extract 0c, in Fig. 4). These ®ndings suggest that
bisphenol A reacts easily with sodium hypochlorite in an
aqueous medium and chlorinated products are detected
in wastewater samples by these methods.
‡
ether of BPA-d14, in which a 0M ±CD3) peak was ob-
served at m=z 368. In the spectrum of bisphenol A, an-
other characteristic fragment peak at m=z 207 results
from the elimination of a trimethylsilyloxyphenyl radical
from the molecular ion. The mass spectra of chlorinated
bisphenol A show similar patterns, in which chlorine-
substituted trimethylsilyloxyphenyl groups are prefer-
3.4. Analysis of chlorinated bisphenol A in ®nal e‚uents
from wastepaper recycling plants
We investigated the presence of chlorinated bisphe-
nol A in the ®nal e‚uents of eight paper manufacturing
plants, where wastepaper is used as the raw material and
the bleaching process involves the use of sodium hypo-
chlorite. Bisphenol A was detected at high concentra-
tions, as shown in Table 1, and is believed to have
originated from waste containing thermal paper and/or
other printed paper.
‡
entially lost; m=z 207 0M ±ꢀClC6H3OSiꢀCH3†3) in
‡
3-ClBPA and ꢀM ±Cl2C6H2OSiꢀCH3† † in 3,5-diClBPA,
3
‡
m=z 241 ꢀM ±ClC6H3OSiꢀCH3† † in 3,30-diClBPA and
3
‡
ꢀM ±Cl2C6H2OSiꢀCH3† † in 3,30,5-triClBPA, and m=z
3
‡
275 ꢀM ±Cl2C6H2OSiꢀCH3† † in 3,30,5,50-tetraClBPA.
3
These fragment peaks are useful for identifying chlori-
nated bisphenol A in the GC/MSanalysis. In addition,
two peaks at m=z 93 and 95 were observed in the spec-
trum of each chlorinated bisphenol A. These peaks
correspond to a dimethylsilyl chloride ion, which might
be formed from the molecular ion by cleavage of a
methyl group of the trimethylsilyl moiety and simulta-
neous migration of an ortho chlorine 0Fig. 3). Similar
migration was reported to occur in the case of 2-chloro-
1-0trimethylsilyl)ethane 0Hill and Mokoto€, 1984).
Chlorinated derivatives of bisphenol A were detected
in concentrations ranging from traces to 2:0 lg=l in the
®nal e‚uents of these eight plants, as shown in Table 1.
Patterns of the chlorinated bisphenol A released into the
®nal e‚uents were classi®ed into three groups: 01) Only
mono-chlorinated bisphenol A was detected 0plant nos.
3.3. Chlorination of bisphenol A with sodium hypochlorite
in aqueous solution and GC/MS analysis of the chlori-
nated products
As a model experiment for the chlorination of bi-
sphenol A with sodium hypochlorite in an aqueous
medium, we carried out the reaction under alkaline
conditions, since wastepaper is treated with an alkaline
solution in the pulping process at paper recycling fac-
tories. Chlorinated bisphenol A was analyzed after
trimethylsilylation with BSTFA to avoid contamination
and improve the limits of detection. The total ion
chromatograms 0TIC) of the products obtained after 5
and 60 min are shown in Fig. 4.
After only 5 min, 3-ClBPA and a small amount of
3,3-diClBPA were produced 0b, in Fig. 4). After 60 min,
peaks of 3-ClBPA, 3,30- and 3,5-diClBPA, 3,30,5-triC-
Fig. 5. Biological degradation of bisphenol A and the chlori-
nated bisphenol A in the supernatant of the activated sludge in
plant 4.

H. Fukazawa et al. / Chemosphere 44 /2001) 973±979
979
2, 6, 7 and 8). 02) Mono-chlorinated bisphenol A and di-
chlorinated bisphenol A were detected 0plant nos. 1 and
5). 03) mono-, di-, tri- and tetra-chlorinated bisphenol A
were all detected 0plant nos. 3 and 4).
results is that sodium hypochlorite should not be used as
a bleaching agent in wastepaper recycling plants.
It seems likely that treatment with sodium hypo-
chlorite in the bleaching process causes the chlorination
of bisphenol A. The di€erences in chlorinated bisphenol
A detected in the e‚uents of these plants may be ex-
plained in terms of di€erences in the pulping process and
treatments applied to wastewater.
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