Hyeon-Seo Cho1, Nguyen Hoang Lam1, Jung Sick Lee2 & Soon-Woo Seol1

1Department of Environmental Oceanography, Chonnam NationalUniversity, Yeosu 550-749, Korea2Department of Aqualife Medicine, Chonnam National University,Yeosu 550-749, KoreaCorrespondence and requests for materials should be addressedto H.-S. Cho (hscho@jnu.ac.kr)

Received 16 December 2013 / Received in revised form 24 February 2014Accepted 5 March 2014DOI 10.1007/s13530-014-0184-y©The Korean Society of Environmental Risk Assessment and Health Science and Springer 2014

AbstractSix organotins including monobutyltin, debutyltin, tri-butyltin (TBT), monophenyltin, dephenyltin (DBT), triph-enyltin were analyzed to investigate a status andeffects of a shipyard to organotins pollution in seawa-ter and sediment from 31 sampling sites, in total, inJinhae Bay. TBT (mean concentration==2.24 ng/L asCl) and DBT (mean concentration==3.69 ng/L as Cl)were found as two dominant organotins in water sam-ples. In sediment samples, TBT, which has mean con-centration of 53.4 ng/g wet weight as Cl and account-ed for 74% in total organotins concentration, in aver-age, was consistently found as the predominantorganotin. Phenyltins were not found or found as lowconcentrations comparing with butyltins. Remarkablegeographic distribution of TBT and butyltin com-pounds showed lower concentrations of those com-pounds in sampling sites located far from the ship-yard.

Keywords: Organotin compounds, Tributyltin, TBT, TPT,Seawater, Sediment, Shipyard

Introduction

Organotin compounds which are widely used asantifouling paint to prevent ship hull from bioincrusta-tion and other structural surfaces immersed in seawater,are one type of endocrine disrupting pollutant (e.g.,butyltin and phenyltin). Organotins are considered to

be dangerous chemicals because of their toxic on non-target marine organisms. These compounds cause anendocrine disruption syndrome called imposex in morethan 190 species of marine gastropods1. A malforma-tion in a bivalve of Pacific oyster (Crassostrea gigas)caused by organotins also reported2.

To be aware of impacts of organotins, the use of TBTwas banned in many countries. France was the firstcountry to ban the use of organotin-based antifoulingpaints on boat less than 25 m long in 19822. FollowingFrance, UK, Australia, New Zealand, Hongkong, NorthAmerica and most European countries have releaselegislation to ban the use of the organotins for smallboat3. South Korea government has banned the use oftributyltins (TBT) based antifouling paint on ships lessthan 400 tons since 2000 and has gradually regulatedTBT use on ships larger than 400 tons from 2001 andfinally on all ships, including ocean going vessels, inNovember 20034. The International Maritime Organi-zation (IMO) banned the use of TBT-based antifoulingpaint on a vessel from 1 January, 2003. However, by2005, the restrictions do not immediately removeorganotins from the marine environment since thesecompounds are retained in the sediments where theypersists3 and a completely alternative antifouling paintregarding both antifouling performance with lowestcost and environmentally friendly properties have notbeen determined5.

Ship building, repairing and antifouling paint appli-cations are conventional sources of TBT pollution6.Despite of this, organotin compounds of TBT contam-ination in shipyards have not been well documented7,8.In addition, available studies on effects of organotinsintroducing to nearby marine environment from a ship-yard are limited. Here, we carry out a seasonal studyduring 2002 and 2003 to evaluate effects of a shipyardto organotins pollution levels in sea water and sedi-ment.

Results and Discussion

Concentration of Organotin Compounds in Seawater

The overall concentration of organotins in seawatersample is shown in Table 1.

Concentrations of butyltin compounds (»BTs) and

Organotins Pollutions in Seawater and Sediment around a Shipyard

phenyltin compounds (»PTs) in seawater samplesranged from ⁄0.4 to 38.9 ng/L as Cl (mean==6.83 ng/L as Cl) and from ⁄0.4 to 2.44 ng/L as Cl (mean==0.08ng/L as Cl), respectively. Except for TBT, highest meanconcentrations of organotin compounds were all foundin fall season. A highest mean concentration of TBT(4.99 ng/L as Cl) was found in winter season. Thebutyltins concentrations found in the present studywere relatively lower than concentrations of butyltinsfrom Canada coast9 and Spain south west coast10.

DBT and TBT were found as two dominant organ-otins in seawater samples. Mean percentages of DBTand TBT concentrations in total organotins were 45%and 42%. The compositions (%) of DBT and TBT wide-ly varied among season (Figure 2). Dealkylation pro-cesses which are affected by light intensity, biodegra-dation, oxygenation of the water column are importantreasons for this seasonal fluctuation of DBT and TBTconcentrations11. In addition, variations of organotinsdischarge from a shipyard should be considered. Per-

centages of phenyltin compounds in total organotinwere 1.2% in fall season and 0% in winter and springseason.

A contour distribution of tributyltins and total butyltincompounds in seawater are described in Figure 3. Con-centrations of butyltins found in sampling sites locatedin inner bay were mostly higher than those located inouter bay. This result might be caused by the existenceof organotins sources and the limited water exchangerate inside the bay reducing dilution of released organ-otins12.

In winter, concentration of TBT and total butyltinswere highly distributed in sampling sites 7 and 12which are located nearby the shipyard floating dock.This result suggests a high input of TBT to seawaterduring sampling period from the floating dock of ship-yard such as shipping activities.

TBT concentrations found in sampling sites locatedin inner bay and nearby floating dock in the presentstudy were mostly higher than the UK environment

34 Toxicol. Environ. Health. Sci. Vol. 6(1), 33-40, 2014

Table 1. Concentration (ng/L as Cl) of organotin compounds in water showed in min-max (mean).

MBT DBT TBT »BTs* MPT DPT TPT »PTs**

Fall ND-3.78 2.67-9.56 ND-5.33 3.11-38.9 ND-0.67 ND-1.78 ND-2.44(1.64) (7.56) (1.26) (10.59) ND (0.4) (0.16) (0.20)

Winter ND-4.89 ND-20.2 ND-18.4 ND-30.4 ND-1.56 ND-1.56(1.40) (4.77) (4.99) (11.01) ND ND (0.09) (0.09)

Spring ND-5.33 ND-10.4 ND-9.11 ND-16.2(0.44) (0.75) (1.19) (2.20) ND ND ND ND

Total ND-5.33 ND-29.6 ND-18.4 ND-38.9 ND-0.67 ND-1.78 ND-2.44(1.01) (3.69) (2.24) (6.83) ND (0.01) (0.07) (0.08)

ND: not determined, below method detection limit for water of 0.4 ng/L as Cl*»BTs refer to sum of three butyltin compounds in each sampling site**»PTs refer to sum of three phenyltin compounds in each sampling site

Figure 1. Patterns showing relative concentrations of individual organotins (mean-%-composition) in water (left) and sediment(right).

Spring

Winter

Fall

Spring

Winter

Fall

0% 20% 40% 60% 80% 100%

Water

0% 20% 40% 60% 80% 100%

Sediment

MBT

DBT

TBT

MPT

DPT

TPT

quality target13 (2 ng/L) and the Canadian water qualityguideline14 (1 ng/L), whereas concentrations of TBTfound in sampling sites nearby the shipyear floatingdock exceeded the standard for TBT concentrationregulated by USEPA Aquatic Life Advisory15 of 10ng/L.

Out of butyltin compounds, TBT presents the high-est toxicity, by disturbing the function of mitochondria,DBT is less toxic and its toxicity action is by blockingthe absorption of oxygen in the mitochondria, whereasMBT has no obvious toxic effect on mammals16. TBThas been found to cause malformations of gastropodsnails and bivalve mollusks at low concentration inseawater as 1 ng/L17. It is worth to noting that, TBT israpidly absorbed by organic materials such as bacteriaand algae or adsorbed onto suspended particles in thewater18 and it is readily incorporated into the tissues ofmany aquatic organisms (e.g. filter-feeding ark shell).To evaluate potential effects of the high toxicity anddominant organotins of TBT in sampling sites of thepresent study to biota, Lee et al. (2009) conducted atransplantation study associated with the present studyon a bivalve of ark shell (Scaphacra broughtonii) dur-

ing 7 weeks. Lee et al. (2009)19 has showed a signifi-cant introduction (p⁄0.05) of TBT to soft tissues(whole body) of ark shell specimens transplanted froma control area to TBT polluted areas near the shipyard.After endpoint of the transplantation test, mean con-centration of TBT in ark shell from shipyard areas washigher than 126 ng/g w.w. as Cl comparing with meanconcentration of TBT in ark shell from the controlarea of 3.4 ng/g w.w. as Cl. Moreover, Lee et al. (2009)also determined that TBT induced from organotin pol-luted areas affected by a shipyard caused reproductivedisruption on ark shell specimens.

Based on immune function studies, a Tolerable DailyIntake (TDI) value for TBT of 0.25μg/kg bw/day wasestablished20. The public health risks associated withTBT from shellfish for the general population and fish-ermen of Taiwan indicated that people who are expos-ed to contaminated oyster presented potential healthrisks21. Based on the above assessments, it is neededemploying more study on composition of ark shell inKorean dietary and accumulation levels of organotincompounds in ark shell to evaluate potential publichealth risks associated with high TBT and other organ-

Organotins Pollutions in Seawater and Sediment around a Shipyard 35

Figure 2. Contour distribution of tributyltin compounds and total butyltin compounds in seawater (upper: tributytin compounds;lower, total butyltin compounds).

128�42′E 128�42′E 128�42′E

35�0

5′N

35�0

5′N

35�0

5′N

35�0

5′N

35�0

5′N

35�0

5′N

128�42′E 128�42′E 128�42′E

Fall Winter Spring

otins concentrations in ark shell body and to releaseadequate considerations in aquaculture area selectionsfor not only ark shell but also other shellfish, whichare popular in Korean dietary.

Concentration of Organotin Compounds in Sediment

The concentration of organotins in seawater sample

is described in Table 2. Concentrations of butyltin compounds ranged from

0.69 to 674 ng/g w.w. as Cl (mean==61.6 ng/g w.w. asCl), whereas a range concentration of phenyltin com-pounds was ⁄0.1-11.2 ng/g w.w. as Cl (mean==0.71ng/g w.w. as Cl). TBT was consistently found as dom-inant organotin in sediment samples (Figure 2). Thisresult was different from the seasonal fluctuation of

36 Toxicol. Environ. Health. Sci. Vol. 6(1), 33-40, 2014

Figure 3. Contour distribution of tributyltin compounds and total butyltin compounds in sediment (upper: tributytin compounds;lower, total butyltin compounds).

128�42′E 128�42′E 128�42′E

35�0

5′N

35�0

5′N

35�0

5′N

35�0

5′N

35�0

5′N

35�0

5′N

128�42′E 128�42′E 128�42′E

Fall Winter Spring

Table 2. Concentration (ng/g w.w. as Cl) of organotin compounds in sediment showed in min-max (mean).

MBT DBT TBT »BTs* MPT DPT TPT »PTs**

Fall 0.27-20.6 ND-37.2 1.30-505 3.08-563 ND-0.31 ND-1.85 ND-2.11(3.93) (3.32) (55.4) (62.7) ND (0.07) (0.54) (0.61)

Winter ND-12.9 ND-42.9 1.21-618 1.21-674 ND-0.40 ND-1.55 ND-1.70(2.89) (13.7) (94.0) (111) ND (0.10) (0.23) (0.36)

Spring ND-3.79 ND-18.4 0.69-364 0.69-382 ND-0.79 ND-10.4 ND-11.2(0.61) (1.75) (22.0) (24.4) ND (0.04) (0.60) (0.64)

Total ND-20.6 ND-49.9 0.69-618 0.69-674 ND-0.79 ND-10.4 ND-11.2(2.23) (5.91) (53.4) (61.6) ND (0.07) (0.47) (0.71)

ND: not determined, below method detection limit for sediment of 0.1 ng/g. w.w. as Cl*»BTs refer to sum of three butyltin compounds in each sampling site**»PTs refer to sum of three phenyltin compounds in each sampling site

organotins in seawater. Mean composition of TBT insediment sample in the present study was 74%. Follow-ing TBT, MBT was next predominant of organotins,which accounted for 9.8%, in average, in total concen-tration of analyzed organotin compounds. A compari-son of TBT in the present study with other studies wasshown in Table 3. The butyltins concentrations foundin sediment in the present study were relatively lowerthan those from Barcelona Harbor, Spain22, West and

east coast, Canada9 but higher than those from TorontoHarbor, Canada23.

A contour distribution of sediment concentration inFigure 4 showed a high accumulation of both trib-utyltins and butyltin compounds in the inner bay near-by the shipyard belonged to sampling site 1, 2, 3, 4and 5. TBT concentrations from sediment sample inthose sampling sites were mostly higher than 50 ng/gww as Cl. TBT and other butyltin compounds concen-tration were lower in sampling sites located far fromthe ship yard.

The entry of TBT into marine environment has beenknown through direct leaching from antifouling paintsinto water, and then adsorption and partitioning to sus-pended particulate matter with subsequent sedimenta-tion to sediment24. Thus, sediment results can providea time-average measure of the organotin species10.Results of TBT and butyltins concentrations from sed-iment core sample described in Figure 5 showed aremarkable geography difference in distributions ofTBT and butyltins concentration between inner bayincluding sampling site 2 and 4, where analyzed TBTconcentrations were mostly higher than 100 ng/g w.w.as Cl and outer bay of sampling site 16, where ana-lyzed TBT concentrations were all lower than 10 ng/gw.w. as Cl. In sampling site 2 located near a dry dockof shipyard, a gradually increasing of TBT and butyltinsfrom 8 cm depth layer to 2 cm depth layer was record-ed. This result suggests an increasing of input of butyl-tins into marine environments which might be associ-ated with a recent growth of producing capacity of theshipyard.

Organotins Pollutions in Seawater and Sediment around a Shipyard 37

Table 3. A comparison of butyltins concentration in the present study with other studies.

SamplingOrganotins concentration

ReferencesYearMBT DBT TBT

Asia Shipyard area, South Korea (31)* 2002-2003 ND-20.6 ND-42.9 0.7-673 This studya

Fishing harbor, Taiwan (21) 2001-2004 n.a. n.a. 2.4-8458 Lee et al.12 (2006)b

Osaka Port, Japan (8) 1995-1996 ND ND 10-2100 Harino et al.25 (1998)b

Coast of Kyoto, Japan (11) 2003 4.3-22 2.3-23 1.2-1.9 Ohji et al.26 (2007)b

Coast, Vietnam (7) 2003 3.9-30 8.1-42.7 8.3-51 Nhan et al.27 (2005)b

West coast, India (29) 2002-2003 n.a. ND-469 5-2384 Bhosle et al.28 (2004)b

EuropeanNorthwest Sicilian coast, Italy (5) 1999-2000 ND ND 3-27 Chiavarini et al.29 (2003)b

West coast, France (7) 1993 25-74 9-29 7-30 Ruiz et al.30 (1997)b

Barcelona Harbor, Spain (12) 2002 35-440 67-2607 98-4702 Diez et al.22 (2006)b

North American Toronto Harbor, Canada (8) 1983 ND-0.08 0.04-0.26 0.03-0.88 Maguire et al.23 (1985)b

Crystal Lake, US (50) 2001-2003 21.3-320 59-350 1.5-14,000 Landmeyer et al.31 (2004)a

West and east coast, Canada (37) 1995 ND-330 ND-1100 ND-5100 Chau et al.9 (1997)b

a: ng/g wet weight; b: ng/g dry weight; ND: not determined; n.a.: not analyzed; *: number of sampling sites

Figure 4. Vertical distribution of TBT and butyltins in sedi-ment core samples.

Conclusions

The distributing status of six organotins includingmonobutyltin, debutyltin, tributyltin (TBT), monoph-enyltin, dephenyltin (DBT), triphenyltin were foundin an area located nearby a shipyard in Jinhae Bay,South Korea. TBT and DBT were found as two domi-nant organotins in water samples. TBT was also foundas the predominant organotin in sediment samples.Phenyltins were not found or found as low concentra-tions comparing with butyltins in both water and sedi-ment samples. Noteworthy geographic distribution ofTBT and butyltin compounds showed lower concen-trations of those compounds in sampling sites locatedfar from the shipyard. More study is needed to evalu-ate potential public health risks associated with highTBT and other organotins concentrations in aquaticanimal which habitat is affected by a shipyard and torelease adequate considerations in aquaculture areaselections.

Materials and Methods

Sampling SitesSea water and surface layer (1-5 cm) of sediment

samples were collected in 3 seasons in Jinhae Bay,South Korea including fall (September 9, 2002; n==20);winter (December 21, 2002; n==20) and spring (March

8, 2003; n==31). 3 sediment core samples were collect-ed in sampling site 2, 4 and 16. Map of sampling sitesis shown in Figure 1.

Extraction and AnalysisSix organotin compounds including monobutyltin

(MBT), dibutyltin (DBT), tributyltin (TBT), monoph-enyltin (MPT), diphenyltin (DPT) and triphenyltin(TPT) were target analytes in the present study. Watersamples and sediment samples were analyzed basedon the methods described by National Institute ofEnvironmental Research (NIER, 2002)32 and Ministryof Marine Affairs and Fisheries of Korea (MOMAF,1998)33, respectively, with some slight modifications.NaCl, HBr 0.1 N, 0.1% troporone/benzene and surro-gate material of tripentyltin chloride (AccuStandard,USA) were added to 1 L seawater sample. The samplewas then shaken vigorously for thirty minute, the upperlayer of benzene was taken into a flask and was con-centrated to 1 mL by a rotary vacuum evaporator(Eyela, Japan). 12 N HCl, ethyl acetate/ethanol (1 : 1)and surrogate material of tripentyltin chloride wereadded to 5g wet weight homogenized sediment sample.The sample was ultrasonically extracted and centri-fuged. The extracting procedure was performed oncemore with the suspension layer. The sample was thenremoved ethanol and concentrated under a rotary vac-uum evaporator. The extracted water and sedimentsamples were then loaded through a silica gel columnfor clean-up step. The samples were allowed to join a

38 Toxicol. Environ. Health. Sci. Vol. 6(1), 33-40, 2014

Figure 5. Map showing 20 sampling sites in fall, winter and 31 sampling sites in spring.

Fall and winter Spring

128�42′E 128�42′E

Study area

Korea

35�0

5′N

35�0

5′N

Grignard coupling reaction with 2 N n-propylmagne-sium bromide and were loaded through a silica gelcolumn again. The solutions were then added with aninternal standard of tetrapentyltin chloride (AccuStan-dard) and were concentrated to 0.2 mL under a purenitrogen gas purging system. Concentration of organ-otin compounds were determined by a Shimadzu GC-MSD QP550A.

Quality Assurance and Quality ControlMethod detection limit for seawater was 0.4 ng/L

and for sediment was 0.1 ng/g wet weight (ww). Therecovery rates of surrogate standards spiked into eachseawater samples and sediment samples ranged from70-130% and from 80 to 110%, respectively. All non-detected observations which below the method detec-tion limit were assigned a value of zero for further cal-culations.

Acknowledgements

This study was funded by the Chonnam NationalUniversity.

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