Volume23/1991/EMECS'90

ToxicE
ffectsofTriorganotinsonthe
AdhesionandGermination‑GrowthofConchosporeso
fPorphyrayezoensis,
RedArga
T.MARUYAMA*,D.SUNt,S.HASHIMOTO*andA.MIURA
キ*TokyoUniversityo
fFisheries,Departmentof
MarineScienceandTechnology,Konan4,Minato,Tokyo,108JapantNationalBureauo
fOceanography,Instituteof
MarineEnv
ironmentalProtection,P.0.B
ox303,Dalian,ChinaキTokyoUniv
ersityofFisheries,Departmentof
AquaticBiosciences,Kanan4,Minato,Tokyo,108Japan
Triorganotins (IDTs) havebeenwidelyuseda
santifoulantsfor ship
sandfishingnets, and the toxic effects ofTOTs onmarineorganisms arebecominga serious
problem. I
nt
hi
sstu
dy,nori(Poゆhyrayezoensis)w
asusedasanor
ganis
mforthebioassayofI
DTs. Norii
sunderst
oodt
obeoneoft
hemostsui
tableorganismsforthebioassayofhazardousc
hemicalsfo
rthefollowingr
easons:(1)Norii
swidely
cultivatedalongthecoastofJ
apan. (2) Eventhoughotherseaweedshavebecome
ext
i
nctd
u
etot
h
ep
ol
lut
i
o
nofc
oast
alw
at
er,nor
iha
ssur
v
iv
ed. (3)Thematerialofa
nyst
agei
nt
hel
ifec
ycl
ecanbeeasilyobtainedinthelabor
atory.
Theobjectives ofthis studyaretoclarifytheeffectiveconcentrations (EC) ofTOT
sdependingonther
atio
sofa
dhe
sio
nofconc
hosporesontheglassplateandt
hegermination (upperportiono
fconchos
por
e
sstan
di
n
gup‑rightandlowerportionof
conchosporesprojectingar
hizoidalfil暉 ent)
‑growth(commencingcelldivision)ofconchosporesofPoゆhyrayezoensis.
MaterialsandMethods(1) 限1aterials: Theconchosporeswereobtainedthroughthefree‑livingcon‑
chocelis ofPorohvra yezoensisUeda (strainZGRW) whichweremaintainedin
thelaboratory. A 1/20PES culturemedium (1/20 Provasoli'senrichedsea‑water) waspreparedusingagedseawaterautoclavedat 120°Cfor20min.
followedbyfilteringwith0.45μm阻 lliporefilter. Fourkindsof tributyl‑tin [bis(tri‑n‑butyltin) oxide ('17B'ID), tributyltinchloride ('IBTCl), tri‑
butyltinacetate (TBTAc) andtributyltinhydroxide (TBTH)] andtwokindsof
triphenyltin [triphenyltinchloride (TPTCl) andtriphenyltinacetate (TPTAc)]wereexamined. Prepared'IBTClandTPTCl solutionswereanalysedbythe
capillarygaschrrnatQCJraphyFPDmethod (HewlettPackard5980)• Theanalys‑edconcentrationsof'IBTCl andTPTClwere99%and 101%of thedesignedcon‑
centration, respectively.
(2) Methods: Adhesiontestsandge
皿 ination‑growthtestsof conchospores
wereconductedbymeansofa cultureofconchospores. Allcultureswere
区~rfo皿ed by incubationina growthchamberata light intensityof 7Klx,
at 15°Candwitha 10‑14hlight‑darkcycle.
(a) Adhesiontests: 0.04mlofTOI'solutionwasdropedontoa glassplateand 0.04mlof thecentrifugedconchosporesuspensioncontaining300‑500
conchosporeswasdroppedontotheTOI'solution. Theconcentrationsofeach
露andtheperiodexposingconchosporestoTOI'were fromOto1,600μg/l
and48h, respectively. Theglass platewasput insealec
1petridishescon‑taininga smallvolumeof 1/20P
認 culturemediumtopreventevaporation.
Thenumberofadl
1er
edconchosporeswascountedw
itl
1amicroscopeafterex‑
posingtheconchospores to'IDTfor 48h.
(b) Germination‑growthtests: Aftertheadhesiontest, theglassplateon
whichconchospores adhered碑 retransferredtot
l1
epetridishcontaining
1/20PESculturernediurnwithorwithoutT
OI's. ConcentrationsofTOI'andthe
periodexposingadheredconchosporestoa 衣 汀 werefr
叩0to280μg/l
MarinePollutionBulletin,Vol.23,pp.729‑731,1991.
PrintedinGreatBritain0025‑326X/91$3.00+0.00
c1991PergamonPres
spie729

MarinePollutionBulletin

and 96h, respectively. Theculturemediawerechangedeverytwodays. The
numberofgennlingswascountedwitha microscopeafterex:匹s
ingconcho‑
sporestoeach'lDTfor 48or 96h.
Resultsanddiscussion(1) Effectsof'IOTsonilieadhesionof conchos)Ores: Figure 1shows iliead‑
hesionratiosof conchosrぬreson比 eglass plateasa functionof rurcon‑centration. The 50%ECofTB'ID,TB'rcl,'I
B'l'
Ac,I'BTii, ~『PTClandTPTAconthea中 esionofconchosporeswasestimatedtobe 120,120,120,820, 30and60μg/1, respectively. TheminimumEC (48‑hECMin.,Ad. inTable 1) of thesix
TOTsontheadllesionof conchosporesonili
eglassplatewasestimatedtobe50,50,50, 500, 5and28μg/l, respectively.'I'here isa largedifference
betweenthe 50%ECandtl
1eminimumECvaluesdependingonthekindsofror.
When比 econchosporeswereculturedin 1/20PES culturem
edilllnwithTPTClof
28μg/l, theconchosporesweredeteriorated.
(2) Effectsof'IOTsoni
lie errnination‑ro叫土 of 比 econchos res: Figure 2
shows thegermination‑growthratiosof concl
1osf)
Oresadllerec
1onto比 eglass
plateasa functionofTOTconcentration. The 50%ECo
f'IBTO,'IB'l℃1,'l'BTAc,'IBTH,'I、
PTClandT四 'A
con廿1egennination‑growiliof conchos匹 reswasesti‑
matedtobe8.0, 27,33,90, 3.6and 6.3μg/l, respectively. Theminim
UinEC(48‑hECMin.,Ger.* inTable 1.
) on比 egermination‑gro砒 hofconchosporeswas
estimatedtobe 1‑2,9, 8‑16, 30‑5‑, 1‑1.6 and 2μg/l, resr.
:iectively. Figure
3 shows 比 egermination‑growthratiosofconchosporesadheredonto 比 eglass
plateasa functionof'IBIOand'rPTCl concentration.'rhe50%ECo
f'IB'IDandTPTCloniliegermination‑grov
たho
f conchosporeswasestimatedtobe 4.0and
1.3μg/l, respectively. Figure 4, whichwas obtained fron1the sarn
eexperi‑mentasFigure 3, showsilieratiosof thenumberof 2‑celledand 4‑celledgennlingsofconchosporesasa functiono
f'I
B'l'
Oa
nd'l'PTClconcentration.
When比 econchosporeswereculturedin 1/20PESwi廿1TB'I
DorTPTCl for 96h,theminimumEC (96‑hEC直 n.,Ger. inTable 1)of'IB'I
DandTPTClwasestimatedtobe 2and<1μg/l, respectively, fr
ornFigure 4. Theratiosof thenumberof 4‑celledgermlingsdecreasedand 比 oseof 2‑celledgermlings incr
easec.
1aCCCTtl
panying比 e increaseofconcentrationofT'B'l
Dor'l'P'rcl.
'l'hephenomena
shown inFigure 4 indicatetl
1atTB'I
DandTPTCl retarded血 egro
砒 ho
f con‑
chosporegennlings. Table 1shows 比 eminimumECof eachTCJl'onilieadlle‑
sionof conchosporesontotheglassplateandgennination‑growthof concho‑
sporesadlleredontotheglassplate. ToxiceffectsofTOTsweremuchmore
effective in凸 egennination‑grav
辻 ho
f conchospores (48‑hE屯 in.,Ger.) 比 aninilieadl
1esionof conchospores (48‑hECMin.,Ad.
), as showninTable 1.
NoriwasveryresistivetoTOTs in比 eadhesionofconchospores, butnot
resistiveto'IDl's ini
liegermination‑gro砒 ho
fa曲 eredconchospores. Theex
amined'l'PTs showedstrongertoxicitymanthe団:
fr
sto 比 eadhesionand廿1e9ern1ination‑growthofconchos匹 res. 曲 entheconchos区）reswerecultur‑
edin 1/20P
声 c
ulturemediumw
itl
1'l
1
PI'Clof 5μg/l, thegermlin9sbecamede‑
formed.
『「『Conclusions(a) Sixkindsof examined'IOI'shinderedtheadhesionof conchos匹 resontheylassplateandretardedt
l1egerrnir
四 tion‑growthofadheredconchos
匹 res.
(b) TheECof'.
邸 sonthegermination‑growthofadheredconchos匹 reswas
muchlowert
l1antheEContheadhesionof conchos区）res. (c) Thetoxicity
of'IOTs examinedwase
stirriatedtobeintl1eorderof TPI'C
l >TP
I
'Ac!
=.T
B
'I
O>
'I
B
TAc!
;
'I
BTCl >>'IBTHontl
1eadl
1esionof conchos区）resontotheglass plate
andthegermination‑growthofadl1eredconchospores. (d) TheminimumECof
TPI℃ 1andT
B'IOontheg
ennination‑g‑rrn,沈 hofadheredc
onchos1.
.
)()
reswasesti‑
matedtobe 1an~2µg/l, res
1::>
ectiv
el
y. (e) Nonobservableeffective concen‑
trationlevelofTPTClonthegermination‑growthofconchos区）resmaybe<O.1μg/1, whenthe safetyfactorof 1/10 isadopted. (f) Whent11econcentra‑
tionof衣JI'sinculturemediumincreased, theconchos1ぬresweredeterior
c1t‑
edandtheg
errnling
sweredeformed.
730

Volum
e2
3/
1991/
EM
ECS'
9080•

60
40

10100~1000
畑(uq/1)Fig. 1Effectsof両 sontheadhesionof
conchosporesofPorphyrayezoensis
ontotheglassplatewhenthecon‑
chosporeswereexposedtoeach両
for 48h.

゜゜螂一

゜

20

100806040200

o‑
i:
sa4
W
12.
:
xuon1?
.
1 qゼ8は51,H迷叩︶

゜rlP)

ーso-i:

10
両100(μg/1)

Fig. 2Effectso
f'lU
I'sonthegermination‑
growthofconchosporesofPorphyra
yezoensiswhentheconchospores
whichadheredontheglass plate
werecultured in1/20P
応 m
ediumfor48hwithouta'lUl'follc,,
妃 db
ye
xpos‑
ingtheconchospores toeach'lUl'for
48h.

叩︶

恥~100op‑e
1 qゼ8H51.Z皮)吼咎 80ーロ..-1•,-I料
甘NQ)

Uヽ

汀li‑
‑
l

40 "
20[ \ ~ - c e l l e d gennlin
<J乱↓。/
両1"~-.1o‑
L‑‑‑L‑LJ

I I1'1叩O

10(μg/1)

両10(μg/1)

Fig. 4EffectsofTI如 andTP'IClonthera‑Fig. 3EffectsofTBTOandT
P'K:
lonthegermination‑gr
四ofconchosp:>
restiosofnumberof 2‑cell改 1りermlingsand 4‑celledgennlingsofconcho‑
of Porphyrayezoensiswhenthecon‑
sporesofPorphyrayezoensiswhenthechosゃ reswerecultured in 1/20P芦mediumwithTBTOorTP'K:
l for96h.
conchosporeswerecultured in 1/20PES
rnediumwith血orTP'ICl for 96h.

Table 1The minimum effective concentrations of TOTs onthe adhesion andgermination‑growth of conchospores of Porphyra yezoensis
units: μg/L48‑h ECn1n,.Ad. 48‑h ECn1n.
.oor・. 48‑h ECn1n.,Uor.* 96‑h ECn1n.
.o(Exp.l)(Exp. 1)
(Exp.2)(Exp.3)

● , .

TBTO
↑BTClTBTAcTBTII

5050505002916301‑298‑16J0‑502=・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ー・・・.
.
.
.
.
.
.
.
.
.
.
.
.
.・・・・・・・・・.
.
.
↑PTC
lTPTAc52
8<1.6<2.8

1‑1.6
2<l48‑h ECn
1n.,uer.*: ECn,n.of TOTs ont
he germination‑growth of concho‑spores when the adhered conchospores ont
he glass plate were cul‑turedin l/20PES medium without a TOT followed liy exposing concho‑spores to each TOT for48h.

731