Environmental
Monitoring and Governance in the East Asian Coastal Hydrosphere
Endocrine Disrupter Compounds (EDCs) in Water
2001 Report, China
Huang Yeru, Shi Junhui, Zhou Li, Di Yian, and Quan Hao
China-Japan Friendship Center for Environmental Protection
(No.1 Yuhuinanlu, Chaoyangqu, Beijing 100029, P. R. China)
Introduction
Recently, increased scientific and public attention has focused on
the potential effects of synthetic chemicals on the hormones, or endocrine,
systems of humans and wildlife. The endocrine system consists of the
glands and the hormones they produce that help guide the development,
growth, reproduction and behavior of humans and animals. The reported
abnormalities due to the hormone disrupting chemicals or endocrine
disrupting chemicals (EDC) are not only abnormalities of sex differentiation
and sex steroid hormone system synthesis, infertility and cancer,
but also death of infectious disease in various animals due to immunodeficiency
and behavioral abnormality due to brain disorder. Monitoring of pollution
levels and distributions of EDCs in various compartments of the environment
should be the first step for the problem of EDC contamination.
Since 1999, China-Japan Friendship Center for Environmental Protection
has been joining the United Nations University (UNU)'s project entitled
"EDC Pollution in the East Asian Coastal Hydrosphere-Endocrine
Disrupting Compounds in Water". The focus of this monitoring
in 2001 is on compounds that are suspected to be EDCs. The targeted
compounds include phthalates, adipate, bisphenol-A and alkyl phenols
(such as 4-t-butylphenol, 4-n-butylphenol, 4-n-pentylphenol, 4-n-hexylphenol,
4-n-heptylphenol, 4-t-octylphenol, 4-n-octylphenol and 4-nonylphenol,
etc.). As always, 2,4-dichlorophenols, Pentachlorophenol and organo-chlorinated
pesticides such as DDT, DDE and HCB were also monitored for the same
water samples.
Sampling
There are four sea areas, i.e. Bohai Sea, Yellow Sea, East Sea and
South Sea, are distributed along the coastline of China. For this
reason, different offshore areas belonging to Bohai Sea, South Sea,
East Sea, Huanghai Sea and Dalian Bay were selected as sampling sites
(Fig.1 and Table 1). The numbers labeled in the map represented the
sampling site in each coastal area. Samples from two different sites
in each coastal area were collected. Seawaters were sampled in 2001
both in summer and winter. At the same time, some of river water in
Beijing and Tianjin were sampled for the targeted EDC monitoring (Fig.2).
view Figure 1. Sampling Sites Map
view
Table 1. Sampling Sites Coordinates
Sample preparation and analysis
Samples collected in glass bottles were transported to the laboratory
within 24hr and stored at 4 in refrigerator. Extractions were carried
out within 24 48hrs generally. Final solutions were stored at -35?
in freezer. The samples were analyzed by gas chromatography with mass
spectrometric detection (GC-MS). The analysis was performed with a
Shimadzu QP-5000 GC-MS (Japan) equipped with a Shimadzu AOC-17A auto
injector (Japan). 30m 0.32mm i.d. DB-1 and DB-5 (film thickness 0.25
m)(J&W Scientific, CA, USA) fused-silica capillary columns were
used for the analysis of targeted EDCs.
Organochlorinated pesticides
1L of water sample added with 30g of NaCl was extracted twice with
50ml of hexane for 10min, respectively. The hexane layer was Transferred
and dehydrated with 3g of sodium sulfate. The dehydrated hexane solution
was concentrated to 1ml by rotary evaporator and N2 purge and transferred
into a pre-conditioned silica gel cartridge for cleanup. The cartridge
was eluted with 5ml of 5% acetone/n-hexane. This solution was further
condensed to 1ml by N2 purge. 2 l of final solution was injected into
GCMS for measurement.
The GC-MS analysis was performed with an oven temperature program
from 70 (hold for 2min) to 130°C at 20°C min-1, then to 200°C
at 5°C min-1 and finally to 300°C at 20°C min-1, injector
and interface temperatures of 280°C, and helium as carrier gas.
Data were acquired in the EI mode (70eV), scanning from 35 to 400
mass units at 0.5s. SIM was used for quantitative analysis. Sampling
rate was 0.2sec. Monitoring ions were listed in Table 2. The injector
was in the splitless mode, the split valve being closed for 2min.
Phenanthrene-d10 and pyrene-d10 were used as internal standards.
view
Table 2 Targeted organochlorine pesticides and their monitoring ions
Bisphenol-A, alkylphenols and chlorinated phenols
1L of water sample was adjusted to pH 2-3 with hydrochloric acid.
30g of NaCl and 100 l of surrogate compound (1ng/ml of bisphenol-A-d16
in acetone) was added into the acidified water sample and extracted
twice with 50ml of dichloromethane for 10min each. The organic layer
was dehydrated and concentrated to 0.5ml by rotary evaporator and
nitrogen purge. 100 l of BSTFA was added into the extract and derivated
for 1hr at room temperature. The final volume was adjusted to 1ml
by dichloromethane. 1ml of the final solution was injected for GCMS
analysis.
The GC-MS analysis was performed with an oven temperature program
from 50 (hold for 2min) to 100°C at 20°C min-1, then to 200°C
at 10°C min-1, and finally to 300°C at 20°C min-1, pressure
program from 40kPa (hold for 5min) to 70kPa at 2kPa/min and hold for
2.5min, injector and interface temperatures of 280°C, and helium
as carrier gas. Data were acquired in the EI mode (70eV), scanning
from 35 to 450 mass units at 0.5s. SIM was used for quantitative analysis.
Sampling rate was 0.2sec. Monitoring ions were listed in Table 3.
The injector was in the splitless mode, the split valve being closed
for 2min. Naphthalene-d8, phenanthrene-d10 and pyrene-d10 were used
as internal standards and Bisphenol-A d16 as a surrogate.
view
Table 3 Targeted phenolic compounds and their monitoring ions
Phthalates and adipate
100ml of water sample and 5ml of hexane were added into a 100ml volumetric
flask successively. Then 10 l of 10 g/ml internal standards, di-n-butylphthalate-d4
and di-2-ethylhexyl phthalate, and surrogate compound (di n-pentyl
phthalate-d4) were added. The volumetric flask was shook for 1min
for extraction purpose. 1ml of n-hexane layer was transferred into
a sample vial for auto sampler. 2 l of sample solution was injected.
The GC-MS analysis was performed with an oven temperature program
from 70 (hold for 2min) to 120°C at 20°C min-1, then to 200°C
at 10°C min-1, to 245°C at 5°C min-1 and finally to 320°C
at 20°C min-1, injector and interface temperatures of 320°C
and 300°C, respectively, and helium as carrier gas (46cm s-1).
Data were acquired in the EI mode (70eV), scanning from 35 to 400
mass units at 0.5s. SIM was used for quantitative analysis. Monitoring
ions were listed in Table 4. The injector was in the splitless mode,
the split valve being closed for 2min. Di n-pentyl phthalate-d4 was
used as a surrogate and di n-butyl phthalate-d4 and di 2-ethylhexyl
phthalate-d4 as internal standards.
view
Table 4 Targeted compounds and their monitoring ions
Results and Discussion
1. Reappearance test for 20ng/ml standard solution of phthalates and
adipate. Good precision of determination and low detection limits
for all target compounds of phthalates and adipate were obtained (Table
5). Relative standard deviations for all phthalates and adipate were
less than 4%. The detection limits defined as 3s were less than 30ng/L.
2. Analysis of recovery test (20ng/ml) for phthalates and adipate.
It was shown that 89-109% of recoveries for all target compounds cab
be achieved (Table 6).
3. Analysis of blank test for phthalates and adipate. Figure 3 and
Table 7 show that good blank test result was obtained in our laboratory.
4. Sample analysis. Samples collected for EDCs determination were
analyzed by the methods described in the manuals provided by the UNU.
view Figure 3.GC-MS chromatogram of blank
view Table 5. Reappearance of target compounds
(phthalates and adipate) ) (20ppb)
view
Table 6 Recoveries of phthalates and adipate (20ppb) in water
Table 7
Blank test of preparation (ng/ml)
Similar to the results of last two years, higher concentrations of
BHCs were detected in Bohai Sea, the most heavily polluted coastal
area in China. BHCs were the first major pollutants in this region.
In addition, DDE, DDD and DDT were found in some of seawater whenever
in summer and winter (Table 8 and Figure 4).
view
Figure 4. Distribution of organo-chlorinated pesticides in seawater,
2001
view Table
8 Concentrations of organo-chlorinated pesticides in water samples
(ng/L) in China, 2001
It was found that most of water samples were polluted by bisphenol-A,
alkylphenols (such as 4-t-butylphenol and 4-nonylphenol) and chlorinated
phenols (including 2,4-dichlorophenol and pentachlorophenol). The
polluting distribution of them in different water samples changes
significantly. 4-Nonylphenol had the highest concentration in all
samples (Table 9 and Figure 5). Meanwhile, there was no 4-n-butylphenol,
4-n-pentylphenol, 4-n-octylphenol that could be detected in all of
seawater. Some of alkylphenols, chlorophenols and bisphenol-A were
also detected in river water samples (Table 10).
view
Figure 5 Distribution of phenolic compounds in seawater
Seasonal changes of alkylphenols, chlorinated phenols and bisphenol-A
are shown in Fig.6 to Fig.8. Higher concentrations of alkylphenols
were distributed in most of summer samples. Samples from Bohai Sea
20, Dalian Bay 1 and Yellow Sea 2 had high concentrations of alkylphenols
in winter.
Samples from Bohai Sea 20, Yellow Sea 1 and East Sea presented higher
concentrations of chlorinated phenols in summer, while others with
higher concentrations in winter.
Higher concentrations of bisphenol-A were monitored in most of summer
samples. Only samples from Dalian Bay 2 and East 2 showed higher concentrations
of bisphenol-A in winter.
view Table
9 Determination of alkylphenols, chlorinated phenols and bisphenol-A
in seawater in China, 2001
view
Table 10 Determination of alkylphenols, chlorinated phenols and bisphenol-A
in river water
view
Figure 6 Changes of alkylphenol concentrations in seawater during
summer and winter
view
Figure 7 Changes of chlorinated phenol concentrations in seawater
during summer and winter
view
Figure 8 Changes of bisphenol-A concentrations in seawater during
summer and winter
Fig.9 illustrated that whenever in summer and winter, the concentrations
of total alkylphenols, chlorophenols and bisphenol-A distributed as
alkylphenols chlorophenols bisphenol-A.
view
Figure 9 Comparisons of concentrations of alkylphenols, chlorinated
phenols and
bisphenol-A in seawater during summer and winter
It was found that high contamination of phthalates always happened
with auto injection mode (Fig.10). For this reason, manual injection
was used for re-evaluation of QA&QC and analysis of winter samples,
some of summer samples and river samples.
view
Figure 10 Comparison of auto and manual injection in phthalate analysis
20ng/ml standard solution
As mentioned above, due to the injection contamination, problem data
(data with * mark) were found in some of summer samples, such as samples
from Bohai Sea, Yellow Sea and Dalian Bay.
Low concentrations of three of phthalates (i.e. diethyl phthalate,
dibutyl phthalate and di 2-ethylhexyl phthalate) were detected in
all of seawater samples with concentrations from 0.011 to 4.87mg/L(Table
11 and Figuer 11). Di 2-ethylhexyl adipate was only found in some
of seawater samples. The concentration distributed from N.D. to 0.094mg/L.
Pollution distribution of targeted phthalates and adipate in different
marine regions changes significantly.
Phthalates and adipated in three river water samples collected in
Beijing and one in Shenyang City were also determined (Table 12).
view
Figure 11 Distribution of phthalates and adipate in seawater, 2001
Conclusion
Endocrine disruptors are synthetic chemicals which have the potential
to disrupt the delicate balance of the endocrine system. Monitoring
of pollution levels and distributions of endocrine disrupting chemicals
(EDCs) in various compartments of the environment should be the first
step for the problem of EDC contamination. Pollution caused by organo-chlorinated
pesticides was serious in some of coastal regions in China. As same
as last two years, BHCs with high concentrations were still the first
major pollutants in Bohai Sea region. Among the phenolic compounds,
4-nonylphenol had the highest concentration in all seawater samples.
All of the seawater samples were polluted by bisphenol-A and 2,4-dichlorophenol.
Up to now, no obvious pollution caused by phthalates and adipate was
monitored.
view
Table 11 Concentrations of phthalates and adipate in seawater samples
( g/L) in China, 2001
view
Table 12 Concentrations of phthalates and adipate in river water (
g/L)
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