Polybrominated diphenyl ethers (PBDEs) and organochlorines in small cetaceans from Hong Kong waters: levels, profiles and distribution.

Abstract

Polybrominated diphenyl ethers (PBDEs) and organochlorine compounds (OCs) were determined in the blubber, liver and kidney of Indo-Pacific humpback dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides) stranded in Hong Kong coastal waters during 1995-2001. Among the organohalogen compounds analyzed, DDTs were the most dominant contaminants with concentrations ranging from 9.9 to 470 microg/g lipid wt. PBDEs in Hong Kong cetaceans, which are reported for the first time, were detected in all the samples with values ranging from 0.23 to 6.0 microg/g lipid wt., with a predominance of BDE-47. Results from this study suggest PBDEs should be classified as priority pollutants in Asia. Higher concentrations were found in humpback dolphins than in finless porpoises, and this was attributed mainly to differences in habitat. Elevated residues of PCBs and DDTs in some cetaceans suggest these species may be at risk.

Full text

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Polybrominated diphenyl ethers (PBDEs) and organochlorines
in small cetaceans from Hong Kong waters:
Levels, profiles and distribution
Karri Ramua, Natsuko Kajiwaraa, Shinsuke Tanabea,*,
Paul K.S. Lamb, Thomas A. Jeffersonc
aCenter for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan
bCenter for Coastal Pollution and Conservation, Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue,
Kowloon, HKSAR, China
cSouthwest Fisheries Science Center, NOAA, Fisheries, 8604 La Jolla Shores Drive, La Jolla, CA 92037, USA
Abstract
Polybrominated diphenyl ethers (PBDEs) and organochlorine compounds (OCs) were determined in the blubber, liver and kid-
ney of Indo-Pacific humpback dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides) stranded in Hong Kong
coastal waters during 1995–2001. Among the organohalogen compounds analyzed, DDTs were the most dominant contaminants
with concentrations ranging from 9.9 to 470 lg/g lipid wt. PBDEs in Hong Kong cetaceans, which are reported for the first time,
were detected in all the samples with values ranging from 0.23 to 6.0 lg/g lipid wt., with a predominance of BDE-47. Results from
this study suggest PBDEs should be classified as priority pollutants in Asia. Higher concentrations were found in humpback
dolphins than in finless porpoises, and this was attributed mainly to differences in habitat. Elevated residues of PCBs and DDTs
in some cetaceans suggest these species may be at risk.
? 2005 Elsevier Ltd. All rights reserved.
Keywords: Hong Kong; Finless porpoises; Humpback dolphins; PBDEs; Organochlorines; DDTs
1. Introduction
Hong Kong, with a land area of 1042 km2and a popu-
lation of 6.8 million people, is located at the mouth of
the Pearl River in the South China Sea (Richardson et
al., 2001). Large scale coastal development, coupled
with sewage, shipping and industrial discharge ensure
that local waters receive a considerable load of trace
organic contaminants (Zheng and Richardson, 1999).
Numerous investigations conducted in our laboratory
have indicated contamination by persistent organochlo-
rines (OCs) in various environmental compartments of
Hong Kong, such as sediments (Kannan et al., 1989),
mussels (Tanabe et al., 1987; Kannan et al., 1989; Mon-
irith et al., 2003) and cetaceans (Minh et al., 1999).
These findings indicate a serious environmental situ-
ation in Hong Kong, which is believed to be a conse-
quence of recent urbanization and industrialization.
There have been no reports on the widely used flame
retardants, polybrominated diphenyl ethers (PBDEs)
in Hong Kong ecosystems. Given that high PBDE con-
centrations are generally found in marine mammals
located at the top of the food chain (Boon et al.,
2002), it is imperative to investigate the presence of these
emerging, bioaccumulative, and possibly deleterious
chemicals in Hong Kong cetacean populations. Finless
porpoises (Neophocaena phocaenoides) and Indo-Pacific
humpback dolphins (Sousa chinensis) are residents of
Hong Kong coastal waters, and as such they may be
0025-326X/$ - see front matter ? 2005 Elsevier Ltd. All rights reserved.
doi:10.1016/j.marpolbul.2005.02.041
*Corresponding author. Tel./fax: +81 89 927 8171.
E-mail address: shinsuke@agr.ehime-u.ac.jp (S. Tanabe).
www.elsevier.com/locate/marpolbul
Marine Pollution Bulletin 51 (2005) 669–676

Page 2

considered indicators of coastal pollution in Hong
Kong.
The present study is aimed at understanding contam-
ination by persistent organohalogen compounds in ceta-
ceans found stranded in Hong Kong coastal waters
during 1995–2001. Residue levels and accumulation
characteristics of PBDEs in the Hong Kong environ-
ment are discussed for the first time in comparison to
OCs, such as DDTs (dichlorodiphenyl trichloroethane
and its metabolites), PCBs (polychlorinated biphenyls),
HCHs (hexachlorocyclohexane isomers), HCB (hexa-
chlorobenzene), CHLs (chlordane related compounds),
TCPMe [tris (4-chlorophenyl) methane] and TCPMOH
[tris (4-chlorophenyl) methanol]. The data may shed
light on the levels of organohalogen pollution in Hong
Kong waters and their potential impacts on cetaceans.
2. Materials and methods
2.1. Samples
The fifteen Indo-Pacific humpback dolphin (S. chin-
ensis) and seven finless porpoise (N. phocaenoides) spe-
cimens used in the present study were found dead in
several locations in Hong Kong from 1995 to 2001. Bio-
logical data of the animals analyzed are given in Table 1.
Blubber, liver and kidney samples were excised from
dead animals, wrapped in aluminum foil, and kept in
a deep freezer at ?20 ?C until analysis.
2.2. Chemical analysis
Analysis of PBDEs was performed following the pro-
cedure described by Ueno et al. (2004) with slight modi-
fication. Briefly, 2–8 g of the target sample was ground
with anhydrous sodium sulfate and extracted in a Soxh-
let apparatus with a mixture of diethyl ether and hexane
for 7–8 h. An aliquot of the extract, after adding 5 ng of
internal standards(13C12-labeled BDE-3,
BDE-28, BDE-47, BDE-99,
BDE-183, and BDE-209), was added to a gel perme-
ation chromatography column (GPC; Bio-Beads S-X3,
Bio-Rad Laboratories, CA, 2-cm i.d. and 50 cm length)
for lipid removal. The GPC fraction containing organo-
halogens was concentrated and passed through 1.5 g of
activated silica gel S-1 (Wako Pure Chemical Industries
Ltd., Japan) column with 5% dichloromethane in hex-
ane for cleanup.
the final solution prior to GC-MSD analysis. Quantifi-
cation was performed using a GC (Agilent 6980N)
equipped with MSD (Agilent 5973N) for mono- to
hepta-BDEs, and GC (Agilent 6980N) coupled with
MSD (JEOL GCmate II) for deca-BDE, having an elec-
tron impact with selective ion monitoring mode (EI-
SIM). GC columns used for quantification were DB-1
fused silica capillary (J&W Scientific Inc.) having
30 m · 0.25 mm i.d. · 0.25 lm film thickness for mono-
to hepta-BDEs, and 15 m · 0.25 mm i.d. · 0.1 lm film
thickness for deca-BDE. Ten major congeners of
PBDEs (BDE-3, BDE-15, BDE-28, BDE-47, BDE-99,
BDE-15,
BDE-154, BDE-153,
13C12-labled BDE-139 was added to
Table 1
Concentrations of organohalogens (lg/g lipid wt.) in the blubber of cetaceans collected from Hong Kong coastal waters
ID YearSexBL (cm)Lipid (%)PBDEsPCBsDDTs CHLsHCHsHCBTCPMeTCPMOH
Finless porpoise
NP00-28/12
NP00-26/12
NP00-25/12
NP01-20/03
NP01-24/05
NP01- 12/04
NP01-15/06
2000
2000
2000
2001
2001
2001
2001
M
M
F
M
M
M
UK
>123
152
145
121
159
163
123
40
34
28
63
65
32
27
na
0.78
0.47
0.23
0.98
0.84
0.28
4.7
7.2
18
1.4
28
22
1.9
63
51
110
26
260
260
9.9
0.34
0.40
0.43
0.14
1.4
1.9
0.15
0.27
0.17
0.10
0.034
0.86
0.31
0.032
0.21
0.11
0.28
0.087
0.16
0.25
0.075
0.076
0.055
0.099
0.024
0.15
0.082
0.019
0.066
0.063
0.044
0.034
0.058
0.066
0.015
Humpback dolphin
SC95-2/9
SC97-10/9
SC97-3/9
SC97-2/5
SC98-7/8
SC98-3/5
SC98-17/1
SC98-17/4
SC00-30/11
SC00-14/2
SC01-06/5
SC01-03/6
SC01-06/02
SC01-28/06
SC01-11/2
1995
1997
1997
1997
1998
1998
1998
1998
2000
2000
2001
2001
2001
2001
2001
UK
M
M
UK
M
UK
UK
UK
M
F
M
M
M
M
F
189
110
265
105
221
112
238
>233
231
252
106
107
160
247
234
10
41
53
51
13
38
9.2
51
34
18
29
32
17
18
75
na
na
0.35
na
1.8
na
na
na
2.6
0.67
0.28
na
na
6.0
1.6
39
5.2
15
12
3.7
2.8
22
18
78
9.4
72
56
38
83
17
380
27
62
82
200
19
49
68
470
51
150
160
280
290
76
1.4
0.19
0.29
0.49
1.1
0.21
0.53
0.41
3.8
1.2
1.7
2.0
6.5
5.9
1.4
0.49
0.18
0.12
1.2
0.57
0.21
0.16
0.18
1.0
0.11
2.2
1.7
0.68
0.69
0.36
0.36
0.21
0.26
0.11
0.16
0.098
0.13
0.23
0.43
0.15
0.35
0.29
0.86
0.36
0.24
0.55
0.017
0.089
0.037
0.19
0.0067
0.099
0.069
0.26
0.087
0.074
0.082
0.20
0.45
0.086
0.23
0.015
0.027
0.053
0.089
0.014
0.024
0.037
0.25
0.032
0.058
0.12
0.16
0.15
0.042
UK: unknown; M: Male; F: Female; na: no data available; BL: body length.
670
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Page 3

BDE-100, BDE-153, BDE-154, BDE-183 and BDE-209)
were quantified in this study. All the congeners were
quantified using the isotope dilution method to the
corresponding
13C12-labeled BDE ranged between 60% and 120%.
OCs including PCBs, DDTs, HCHs, CHLs, HCB,
TCPMe and TCPMOH were analyzed following the
method described by Kajiwara et al. (2003). Another ali-
quot of the extract was subjected to GPC for lipid
removal. The GPC fraction containing OCs was concen-
trated and passed through an activated Florisil column
for clean-up and fractionation. Quantification of PCBs
and most of organochlorine pesticides was performed
using a GC (Agilent 6980N) equipped with a microelec-
tron capture detector (micro-ECD) and an auto-
injection system (Agilent 7683 Series Injector). The
GC column used for OC analysis was a fused silica cap-
illary (DB-1; 30 m · 0.25 mm i.d. · 0.25 lm film thick-
ness,J&W Scientific Inc.).
quantification of TCPMe and TCPMOH were per-
formed using a GC-MSD (Agilent 5973N) in SIM mode
equipped with an autoinjection system (Agilent 7683
series injector). The concentration of individual OCs
was quantified from the peak area of the sample com-
pared to that of the corresponding external standard.
The PCB standard used for quantification was a mixture
of 62 PCB isomers and congeners (BP-MS) obtained
from Wellington Laboratories Inc., Ontario, Canada.
Concentrations of individually resolved peaks of PCB
isomers and congeners were summed to obtain total
PCB concentrations.
Procedural blanks were analyzed simultaneously with
every batch of five samples to check for interferences or
contamination from solvents and glassware. Lipid con-
tents were determined by measuring the total nonvola-
tile solvent extractable material on subsamples taken
from the original extracts. The concentration of organo-
halogens are expressed on a lipid weight basis unless
otherwise specified.
13C12-labeled congener. Recovery of
Identification and
3. Results and discussion
3.1. Contamination status
Concentrations of PBDEs and OCs detected in the
blubber of finless porpoises and Indo-Pacific humpback
dolphins from Hong Kong coastal waters are shown in
Table 1. Among the organohalogens analyzed, DDTs
ranked first followed by PCBs > CHLs > PBDEs >
HCHs > HCB > TCPMe > TCPMOH. This is the first
assessment of PBDE contamination in the Hong Kong
environment. For all the contaminants, higher concen-
trations were found in humpback dolphins when com-
pared to finless porpoises. This difference can be
accounted for by differences in habitat. Humpback dol-
phins inhabit the western waters of Hong Kong, which
are close to the Shenzhen economic zone, and their hab-
itat is estuarine (Jefferson, 2000). However, finless por-
poise inhabit southern and eastern waters of Hong
Kong which are more oceanic-influenced (Jefferson
et al., 2002a). Similarly, significantly higher concentra-
tions of OCs were observed in Little Egret (Egretta garz-
etta) eggs from Mai Po in the western part of Hong
Kong when compared to Night Heron (Nycticorax nyc-
ticorax) eggs from A Chau in the eastern part of Hong
Kong (Connell et al., 2003).
Summed concentrations of PBDE congeners mea-
sured in the blubber of finless porpoises and humpback
dolphins ranged from 230 to 980 ng/g lipid wt. and 280
to 6000 ng/g lipid wt., respectively (Table 1). It is note-
worthy that PBDE residues in cetaceans from Hong
Kong were apparently higher when compared to north-
ern fur seals (Callorhinus ursinus) from the Pacific coast
of Japan (Kajiwara et al., 2004), and bottlenose dol-
phins (Tursiops truncatus) from the South Atlantic US
coast (Kuehl et al., 1991). The levels observed in this
study were comparable to harbor seals (Phoca vitulina)
from San Francisco Bay (She et al., 2000) and harbor
porpoises (Phocoena phocoena) from British Columbia
(Ikonomou et al., 2002). The results confirm that devel-
oping countries can also be a source for PBDE contam-
ination. Our previous study to elucidate geographical
distribution of PBDEs using skipjack tuna showed high-
est concentrations of PBDEs in samples from the East
China Sea (Ueno et al., 2004). The plausible reasons
for the high levels of PBDEs observed in this study
may be the daily discharge of large quantities of un-
treated sewage into coastal waters of Hong Kong (Chan
and Yung, 1995) as well as export of waste electric prod-
ucts (computers, televisions etc.) used in developed
nations to Asian developing countries such as China
as trash (Hileman, 2002). These findings are consistent
with studies associating high PBDE concentrations with
point-sources such as wastewater treatment plant
outfalls (Hale et al., 2001).
In Hong Kong cetaceans, DDTs and PCBs were the
predominant contaminants. DDT levels were high when
compared to Dall?s porpoises (Phocoenoides dalli) from
Japan (Kajiwara et al., 2002) and spinner dolphins (Ste-
nella longirostris) from the Philippines and India (Pru-
dente et al., 1997), but were lower than some highly
polluted areas in the Mediterranean (Kannan et al.,
1993). High DDT levels found in Hong Kong cetaceans
are related to DDT utilization in this country until 1989
(Phillips and Tanabe, 1989), and possible continued use
in surrounding waters of China. As for PCBs, concen-
trations were higher than in humpback dolphins from
Bay of Bengal, India (Prudente et al., 1997) but lower
than in diseased cetaceans from the Mediterranean Sea
(Kannan et al., 1993; Corsolini et al., 1995). A large
proportion of PCBs still remain in transformers and
K. Ramu et al. / Marine Pollution Bulletin 51 (2005) 669–676
671

Page 4

capacitors in China (Zhou et al., 2001) and this may be
one of the contributing factors to the high levels of PCBs
observed in this study.
3.2. PBDE congener profiles
Of the 10 congeners analyzed, a total of eight congen-
ers from di- to hepta-BDE were identified in Hong Kong
cetaceans (Fig. 1). BDE-3 (mono-BDE) and BDE-209
(deca-BDE) were not found above the detection limits
of the analysis, which were 0.01 and 0.5 ng/g on lipid
wt., respectively. Similar PBDE congener patterns for
humpback dolphin and finless porpoise were found.
BDE-47, BDE-99 and BDE-100 made up 90% on
average of the total PBDE load. These results are in
agreement with the general PBDE congener pattern
reported in biological samples (Ikonomou et al., 2002).
It is not known whether China uses OctaBDE and/or
DecaBDE. In the present study, BDE-183 could be
detected in trace amounts only in a few individuals.
Debromination of BDE-183 to lower congeners may
be the reason, as experimental studies in fish have shown
debromination of BDE-183 to BDE-154 (Stapleton
et al., 2004). BDE-209, the major congener of DecaBDE
formulation, was not detected in any of the samples,
suggesting its relatively low bioaccumulation potential.
As of now, the type of commercial PBDE mixture used
in and around Hong Kong is not known. Hence, infor-
mation on this aspect is vital to compare the congener
profiles in the present study to that of the commercial
mixtures.
3.3. Residue composition pattern of organochlorine
pesticides
The residue composition pattern of the various orga-
nochlorine pesticides is shown in Fig. 2. Percentages of
the main components of DDTs varied between the spec-
imens. The major constituent of DDTs was p,p0-DDE,
accounting for more than 40% in both humpback dol-
phins and finless porpoises. Concentrations and propor-
tions of p,p0-DDT in both the cetaceans were higher in
the present study when compared to finless porpoises
from Japan (Arakane et al., 2002), suggesting that
DDT is still being used in and around Hong Kong.
The wide range of DDT concentrations, and DDT com-
position in waters and sediments in Daya Bay, Southern
China, also suggest recent inputs to the coastal waters
(Zhou et al., 2001). The Pearl River Estuary, just west
of Hong Kong, drains a vast area of agricultural lands
in southern China, and the continuing use of DDT in
this area is therefore very much possible. Overall, in
all the samples of humpback dolphins and finless por-
poises analyzed, the percentage of p,p0-DDD was rela-
tively high. Harbour porpoises from the Black Sea,
which has a reductive environment also had high
proportions of p,p0-DDD (Tanabe et al., 1997). The
anaerobic conditions prevalent due to the large quanti-
ties of sewage discharged as mentioned before may be
0
10
20
30
40
50
60
70
BDE-15
Contribution to the total PBDEs (%)
Finless Porpoise
Humpback Dolphin
BDE-28BDE-47
BDE-99BDE-100
BDE-153
BDE-154
BDE-183
Fig. 1. PBDE congener patterns in finless porpoises and humpback
dolphins from Hong Kong coastal waters. Vertical bars represent
contribution of each congener to total PBDEs concentration.
Finless Porpoise
Humpback Dolphin
Finless Porpoise
Humpback Dolphin
0
50
100
Finless Porpoise
Humpback Dolphin
Composition (%)
α -HCH
p,p’- DDE
cis-chlordane
DDTs
HCHs
CHLs
p,p’-DDD
p,p’-DDT
cis-nonachlor
trans-nonachlor
oxychlordane
β -HCH
γ -HCH
Fig. 2. Percentage compositions of organochlorine pesticides in the blubber of cetaceans from Hong Kong coastal waters.
672
K. Ramu et al. / Marine Pollution Bulletin 51 (2005) 669–676

Page 5

responsible for high p,p0-DDD levels in cetaceans. Sedi-
ments and fish analyzed from inland water systems of
Hong Kong also showed high p,p0-DDD levels (Zhou
et al., 1999).
For CHLs, trans-nonachlor was the dominant com-
pound, followed by oxychlordane, cis-nonachlor and
cis-chlordane. This pattern is similar to previous studies
dealing with marine mammals (Minh et al., 1999;
Watanabe et al., 1999). The proportion of cis-chlordane
in humpback dolphins was more than in finless por-
poises, perhaps because humpback dolphins are a coast-
al species and there might have been fresh inputs of
CHLsintothecoastal
environments.
For HCH isomers, b-HCH was the most predomi-
nant isomer in both the cetacean samples. Minh et al.
(1999) suggested that the predominance of b-HCH
among HCH isomers reflects its persistence towards
enzymatic degradation.
watersfromterrestrial
3.4. Contaminant distribution between tissues
To understand contaminant distribution between tis-
sues, blubber, liver and kidney samples from some indi-
viduals of finless porpoises and humpback dolphins
were analyzed. Concentrations of organohalogens in
the three different tissues of both species are shown in
Table 2. The lipid normalized PBDE and OC concentra-
tions in various tissues were highest in blubber when
compared to the other tissues, consistent with the previ-
ous data reported for OCs (Watanabe et al., 1999).
PBDE congener profiles in all three tissue samples ana-
lyzed were similar. BDE-47 was the dominant congener
and accounted for 70% of the total PBDE load. Simi-
larly, no tissue preference for BDE-47 was found for
marine mammals from the North Sea (Boon et al.,
2002). For fishes from the lakes of Europe, higher
BDE-47 was found in the liver when compared to the
muscle (Vives et al., 2004). In the case of DDTs, the pro-
portions of metabolites were higher in the liver and kid-
ney when compared to blubber. p,p0-DDT percentage in
the liver of both finless porpoise and humpback dolphin
was less than 1% (Fig. 3). The liver is the main center for
detoxification of xenobiotics and this may be the reason
for the lower percentage of p,p0-DDT. Secondly, the
liver of striped dolphins (Stenella coeruleoalba), which
comprise mainly phospholipids, had lower proportions
of p,p0-DDT (Fukushima and Kawai, 1981). Thus the
nature and levels of total lipids in a tissue is an impor-
tant factor influencing the uptake of lipophilic sub-
stances. No distinct trend could be found for CHLs
and HCHs among the three tissues. For two immature
finless porpoise samples, concentrations of organochlo-
rines were higher in liver when compared to blubber.
The lipid percentage in liver was also high, which sug-
gests that mobilization of lipids from blubber had taken
place. When mobilization of lipids occurs, both lipids
and liphophilic pollutants are drawn to the liver for
catabolism; therefore an increased concentration of
both lipids and xenobiotic compounds is expected. The
Table 2
Concentrations of organohalogens (lg/g lipid wt.) in blubber, liver and kidney of cetaceans collected from Hong Kong coastal waters
IDYearSex BL (cm)Tissue Lipid (%)PBDEsPCBs DDTs CHLsHCHs HCB TCPMeTCPMOH
Finless porpoise
NP00-25/12 2000F 145Blubber
Liver
Kidney
Blubber
Liver
Kidney
Blubber
Liver
Kidney
Blubber
Liver
Kidney
28
7.1
3.7
32
4.3
2.1
63
11
3.2
27
12
10
0.47
0.38
0.22
0.84
0.29
0.29
0.23
0.25
0.089
0.28
0.071
na
18
14
6.7
22
9.3
7.8
1.4
2.7
1.4
1.9
2.1
1.1
110
95
43
260
73
61
26
60
25
10
19
9.4
0.43
1.4
0.21
1.9
0.44
0.41
0.14
0.32
0.15
0.15
0.16
0.29
0.10
0.12
0.077
0.31
0.13
0.11
0.034
0.066
0.036
0.032
0.067
0.041
0.28
0.57
0.19
0.25
0.36
0.19
0.087
0.17
0.11
0.075
0.13
0.057
0.099
0.27
0.078
0.082
0.061
0.061
0.024
0.096
0.048
0.019
0.55
0.35
0.044
0.16
0.052
0.066
0.22
0.089
0.034
0.10
0.048
0.019
0.033
0.027
NP01-12/4 2001M 163
NP01-20/3 2001M121
NP01-15/62001UK 123
Humpback dolphin
SC00-30/11 2000M231 Blubber
Liver
Kidney
Blubber
Liver
Kidney
Blubber
Liver
Kidney
34
6.3
3.6
25
11
5.3
29
3.4
5.6
2.6
0.79
1.0
1.6
0.34
0.33
0.28
0.25
0.26
78
27
18
17
0.61
4.6
72
30
18
470
230
83
76
67
28
160
150
91
3.8
2.3
0.88
1.4
1.1
0.73
1.7
1.6
0.98
1.0
1.3
0.46
0.36
0.60
0.32
2.2
2.4
1.5
0.43
0.85
0.24
0.24
0.55
0.16
0.35
0.52
0.27
0.26
0.19
0.12
0.086
0.058
0.062
0.074
0.056
0.053
0.25
0.33
0.0046
0.042
0.14
0.055
0.058
0.16
0.051
SC01-11/22001F234
SC01-6/52001M 106
UK: unknown; M: Male; F: Female; na: no data available; BL: body length.
K. Ramu et al. / Marine Pollution Bulletin 51 (2005) 669–676
673