Document 4Q4deNnvo7EVaaDJnq29nMXx1
DDT and PCB in Marine Animals from Swedish Waters
S. JENSEN
Inultute of Aostytlcsl Chemistry, ttockholm
A. G. JOHNELS M. OLSSON Swedish HuMum of Natural History,
Stockholm
Analyses of pesticide residues In a wide range of marine organisms from the coastal waters of Sweden show that there Is a marked contamination In the Baltic. There are signs of an increase In polychlorinated biphenyls (PCB) from north to south in this srea. Exceptionally large amounts of residues were found In white tilled eagles from the archipelago of Stockholm.
G. OTTERLIND Imdiuu of Marine Research, lysskll
.
Cblosjnatxd pestioidos ean spread in living matter, extracted from fish from the southern Baltic proper.
and they are now present all over tho world. In 1906 This was unseporated.
(ref. 1), it waa discovered that aome previously unknown Horaogonatos of one or more mussels were analysed.
rubstannos isolated in analyse* of peetioide residuea woro In tho fish, axial muscle tissue extracted from the dorsal
polychlorinated biphenyls (PCB). In Sweden, they occur side above the lateral line, approximately a third of the
in tho natural environment in the some amounts as the length from the tail was analysod. In nino out of eleven
chlorinated pesticides''*. Rooently, PCB has been found salmon, the samples had to be token immediately behind
in organisms in the Netherlands, Great Britain*-* and the the head (only heads were available). Host of tho samples
United States*. PCB is used almost exclusively in Indus, _. from the seals ware taken from the blubber in the tail.
try, and It seems to be more persistent than DDT. Wo In two seal pups from the Gulf of Finland, the samples
have assessed PCB and DDT (including metabolites) were from the fore leg, and in one grey seal from the
contamination in Swedish marine ecosystems by analysing Baltio proper, the sample was liver. It is reported',
176 samples. The hydrographical conditions along tho however, that in seals the ohlorinsted hydrocarbon con
8wodith coasts are not uniform so the residues are classi tent in the fat is approximately oonstent throughout the
fied aooording to tho four regional subdivisions shown in different ports of tho body. As a rulo, tho spocinvons.
Kig, 1. Fow sompios woro taken from tho Sound and so or parts of tho spooimons, woro eont to tho 8wcdish
this oroe hot been included in the Baltic proper.
Musoum of Natural History immediately aftor oapture
Tho spocioe studied woro: (1) tnussol (Mytihu edulu); and wore stored at -- S0 C. Throo seal toils from tho
(3) herring (Olupeo Harmfut)i (3) plaice (PUuronecU* archipelago of Stockholm and ono from tho Ouif of
pfolura) i (4) picked dogfish (Sgualur aoan&ias}; (6) Bothnia were, however, kept by the hunter for six montlis
cod (Oadu* *torhsM)i (6) salmon (Salmo talar) j (7) grey in a non-hooted room. In the homogenised eggs of the
scot (Halichoenu fryjrvr) j oommon seal (PAoea vitulina) guillemot the fat varied from 3-6 to 11 per cent probably
and ringed seal (Kim kitpida); (8) guillemot (Uria because homogenisation before aliquotation was not
Beige); (9) whits hailed eagle (Haliaoeiu* tShioilla); (10) quite perfeot. Samples were taken from both tho pectoral
egg* of white tailed eagle) (11) heron {ArxUa oinrrta). muscle and brain of the white tailod eagle. All the eagles
Three sample* of separated fish oil were also analysed. were found dead and in some cases in a state of decay,
Two were taken from the Norway pout (Borooffadut and all the eggs were either addled, rotten or dry. In
umarln) and one from-herring* from the northern part of the heron, pectoral muscle only was analysod.
the west ooast. One cample (largely herring oil) was also DDE was ths principal metabolite of DDT found.
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NATURE VOL- 224 OCTOBER 18 i9t,
FI*. 1.
DDD wu foimd in small oonoeotratioos, not usually more than 10 per oent of the * DDT, in most samples, (t DDT stands for the sum of DDT and DDEr-DDE was multiplied by 1-11 to oorreepond to the original DDT.) For seals from the archipelago of Stookholm and for salmon from the Baltio proper whion had relatively large amount* of DDD, s DDT stands for the sum of DDT, DDE and
DDD. We analysed all the samples using gas ohromatogrsphy
and electron oaptme detection. Confirmations were carried out with double column systems combined with ' treatment* with sulphurio acid and potassium hydroxide*.
We found that the principal PCB components were POB numbers 7-U (low npmbe? is equal to a low chlorination degree), but the mussels also oontained the lower number* (the POB Composition being similar to elophen A SO). Tim POB amounts given in Table 1 are, neverthe less, the sura of all PCB oomponenW found in the samples although the relative"amounts of the different numbers vary. The results suggest that the low PCB numbers are metabolised or exoreted fester than the higher number*, so that there is an inoroaeo of the latter as it passes through a food chain.
An attempt to quantitate PCB has been made in Sweden', but because the method is still rather rough tho values may be oorreot only within a factor of I. The method is indirect beoause all the PCB oompononts have not been isolated yet, and it is based on a combination of mass spnotroroetry, mioro-oolorimetrio and electron cap ture detection. For each twenty samples a blank on the solvent and a residue-free plaioe sample with added pestioides (lindane, aldrin, ppDDE, dieldrin, pp'-DDD
mid p/i'-DDT) \vi>ro also iinulywil, It. iovriv
80 por cont , Init its normal in residim analysis' wu ihhi^ .
oornolinii.
1
Tho lutMiii figures in Tnhlo ) uro ntlculni i-d frnn,
nvorago vuliia of each locality within Ilia four ri-gjr>,,
'J'ho residue valium nro bimud both on fresh tissue nn<)
hoxano oxtruclublo fut. Tho linures for fresh tjMUt) l('
comparablo with roportod values from other <ountrit
Wo believe, however, that tho fat vnlue^ uro of purlicul*,
intoroat from an ooologicul point of view. Fat u import,,,,,
in tho transport of onorgy ond os a onrrior of (ho residue,
botweon tho spooioe in the food ohain. Furthermore, thci,
is n great seasonal variation in fat content within ib
populations. Tito dilTi'ronre Is.i woon the grntle .t uad il,,
smallest rewidue lovol in thn extractable fut of i,,thvi<lu*|,
of ono spooics at a given time, in a givon place, m less than
in fresh tissue. Tho fat content of herring munch, fw
oxample, varied from about 1 per eont in the spring
about 10 per oent in tho autumn. Our discussion tr,li thorefore be basod largely on residue levels m oxt rnetaRj,.
fat.
Mussels from tho wost coast of Swodon liavo lo*f,
' average values of s DDT and PCB than from the Baltic
proper and the archipelago of Stockholm The level
s DDT in mussoU from the Dutch, Wost German and
British ooaate''' lias an upper limit similar to Out u,
mussels from the Baltio proper and thn archipelago of
Stookholm.
DDT contamination in individual plaice, cod and j*
fish oil is greater in tho Baltio proper than off the wen
coast of Swodon, and there is little or no overlapping
tho residue values. In the oaso of PCB, a plaico from th,.
vory polluted Idefjord in tho west oonst increases tl
avorugo value for tho west ooust samples from 0 00 to i
p.p.m. Other individual samples of fish front tho uc-i
ooast contain PCB rcsiduoe of the same magnitude ,
residues in speoimous from the Baltio. This may lx- tfy
result of coastal contamination. The piokod dogfish,
which lives more in the open seo, scorns to have the sany
amount of c DDT, but aamallor amount of PCB than other
fish from the west coast of 8woden.
Tho samples of herring from the Baltio proper, the
archipelago of Stookholm and the QuJf of Bothnia hd
largo reeriaues of t DDT. No herring from the west ooast
of Sweden has been studied. Recently we analysed eight
herrings from the west ooast. On fat basis the mean
value werei t DDT, T9t DDT, 0-86| and PCB. 0 75, in
food agreement with the fish oil values (see Table 1) uvenile herring from the Dutoh Wadden Sea (ooasuii
waters)*'* oontained DDE residues in fresh tissue with ts
upper limit of the same magnitude as in herring from th*
Baltio area.
Residues of PCB and t DDT in one sample of fish od
from the southern Baltio proper were about five to ten
times greater than the three samples from the west ooatt
of Swoden. The figures for the latter are similar. Thi*
is in aooord with residue* in fat in fish from the respective
areas.
One herring from the Sound had a much tprgrr content
of PCB (23 p.p.m.) than the horring from the rest of the
Baltic aroa. This increased the average value In this arcs
from 4-6 to 0-8 p.p.m. Cod and plaice from the Sound aln
had a larger PCB content than specimens from the Baltic
proper and off tho west ooast. This suggests that there n
looal contamination of PCB in the 8ound. Furthermore,
tho mean levels of PCB noted in herring were smaller
in the Gulf of Bothnia then in the rest of the Baltic.
The vagrant Baltic salmon had about ten times more
ohlorinatod hydrocarbons residue than a sample reported
from Groat Britain*.
The seals from the Baltio proper, the archipelago of
Stockholm and the Gulf of Bothnia contained largo
amounts of residues of both t DDT and PCB, about ten
times greater than amounts found in Great Britain'.
Canada* and the Netherlands". One specimen from
DSW 029723
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' ATDfE VOL M4 OCTOBER IB I6B0
249
4, /irohipolngo of tkooklMilm ImwI UIO p.p.m, in fid, .^rc-iuiug (lie moon vehio for thin port of U10 oonat from ill p.p.m. to ITO p.p.m. Tho levels of PCI! decrease juxtt south to north. Thin fact, together with lower uc-mge valuoa of 1*C1I in herring front Mwtlulfof llolhuiii, indirsh'* decroiuijig 1KHJ rxnttoiniimtion from Month to i,,irili ii> the Ihillto, ft'iil ptipn, om> win'k ohl, also eonliiitnl large itmmiuU of 4 J1DT an<l It III ivmhIiioh, mid itl mill* from Ihe slianiuh of one of I-Ikso j*i(ih ImiI |.|n>
on* level.
OtoUrinot eggs fWmi U10 JtfolUc proper provided nddi. informsUoh on the eonlnmlnaticHi of tlio Baltic.
fU- menu* of DDT ottd PCD in egg* (wet weight) wore W p.p.m. and ltt p.p.m. rtw|x>otivoly, which for 4 Dm'
,. shout ton tillKw tlio lovrln roporUnl from Uront llrnftin*'*1"**. 'Jlte BaMic lovels. both for 1 nDTmut FtIII, yd about fmr to flvo timrw gt-nub* than htvok roporhxt front the neat coaat of tlio United fitahvi4, If tlw ftgnriw
(,-t nsklws in fat Arc compared. In gtllllomoi <xjg from the Baltii, as mitoh aa 87 pit* oont of t DDT wd* DDE.
The population of white tailed eagle* in Bsreden seems
. lu be on the decline. Only about two of ten pairs netting in the nrcliipelago of Stockholm succeeded in hatching .luring the pa*t few year* (E. Lorseon, personal com
; immiratirm)- All specimens of white tailed eagle atudied up 10 1 he present oontained at least three aooumulating iiibstanroa known to be toxio. These are DDT met*Mite*, PCB and mercury compound*14. Figure* for four birth nr.' reported in Table 1. A fifth specimen i* not
iimhidod bncnuHO l.lio lot cniilout win uni .(.1 . <,,,,... .t,
but tho pectoral imieclo noil brain timim .if Hih lord {wot woight) cmdnini'd I1H) nml Dl) p.p.m. ri-M|M all' v of DDT (nn DDK), ami 2110 nml Sf4 p.p.m. nf l'( II. Tun HinviiiHMiH fnmi Hurtlmrn Kwiilmi, nun nf wlm-li di.-d hv m-i'idmit, ooiduiinxl 211 p.p.m. (I-H 3-4) nf DD T (m 1)1 if;, nml 3-0 p.p.m. (1-8 M O) nf l*(JM in miiHclo tium, 1Jwx-uml having l-g p.p.m. DDT (nn 1 >|>Id> nml 12 p.p m. It511 ill hruiti tinmu>. T'lm figmxxi from tlm arrhi|H-liign nf BUmkHotm imi Hum n hundred tinnw Inrgur, miugi mI mg tliat tiioro n a strong cnnlatninutinn in thin unui.
It in wall known that nwHliMw nf chlnrinnh d hyiln.. civtImiiih tend toIxjgmulor in tlm higlior trophic Invrls limn Hi tl> lowor. 80100 nimplifiod food ulmiu rrlutimm i nn bo dndtKxxl from tho llguma in Table I. Tln-wi nr., lii.li in I*ail, (Ml to gtiillmiHit, (Ml to hofnu ami hull to wlnlo tail' d
oagto, In all eat**, lltn inoroonn in hwiildisi from pmy in
irodntor to at hwot PSl-fotil in both wlmtn Iihmiiu and lut.
11 U10 eftglo and boron, tlio incroonu u up to I On imu but for both of these peases some important food organ-
i*ma are mlaeing in thi* investigation. There are indica tion* (Table 1) that the percentage of DDE and of c DDT inareaaee as it progresses from lowor to higher trophic
lovols. Thi* may be the result of decomposition of 1)D T within the organism*. In alt the sample* from birxl-i,
the residues are almost exclusively DDE, while in seals and fishes there is up to 00 per oent of DDT. This differ ence may be the result of differences in metabolism14.
As previously mentioned, the seals from the archipelago
Tstd* 1. ooxcrairTXJ.no* or o***jocmlo*is oom-ouxw 1* avsciux 0ARIXK oaoixitKu I8S6-S8
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0084
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0008 (0-003-0 009)
0 005 (OS01-0-008)
015 (OStS-DU)
0004 (tr*t--0 008)
0003 (ad.--0 000)
0081 (0018-0*1)
0021 (0 001-0 055)
0 019 (0008-0 030)
0 16 (0054-010)
Pr rent fnl 13
Oft to 4-0 :>)
030 (0 lft-0 34)
90 (6 7-H) 100
milk i>fit proper loci, the Sotutd
f
Oft. 1M. Doc.
Dec. 1M7. J*D. IH*
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hrpt. t06T
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(7-4-58)
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ts (1-1-S-t)
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001 (0-000-4707)
0 88 (0 005-11)
0-014 (0-000-0-014)
0 081 (0017-011)
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0-40 (0011-1 1)
0011 (0001-0019)
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0 034 (0012-0 057)
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11.d. N.d. n.c. k.O.
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.DPT .UixtafiK DPT DDBeDDD. **)iaoas*dM*l. Un*MrwpsrUYat)r 41 ew <*t DDD In .ODT. Un nets Ifur* beln* K pe' rent s.r., Kot wtlmsled. a*.. Mot SHseted.
DSW 029724
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NATURE VOL. 224 OCTODCR la 1963
of SiiH-kln>lii>, Blurt'd in a unit-braird room for nix months, lunl A groutor proportion of DUO (n|> to 40 por cont of 1 >1X1*). <Wul imoitAunoiwIy nnmllor levels of DDT itself, thoh it i-kIhv erwtx, Thin ooutii Imvo boon cnuwd hy post mortem metabolism try microorganisms", On Uio oilier htiiMl, Uio ringed seal from tlie Qiilf of Bothnia, stored in Oto aamo way ns for na wo know, hod only about S jv-r rout of DDD, bt this low figure may bo oorreotod with tho uncertainty of DDD estimation At the time when
Uw other seal* were analysed. This riifleronoo botweon the nrrliipctngo IMk nnd tiro other seals, howover, oould be related to the faet that tho large amount of pollution and tho tond-untor rotation in tho arohipolago of Stockholm produce a higher mierobiokigiool Activity In tho water, transforming" DDT to DDD and possibly DDE.
Little i known about the toxicity of FOB in tho levols found by u. PCB haa, howover, boon proved to cause
williologicnl changes in loborntnry animali", and was found to bo among tho ten most potent chemicals among a hundred tested by injeotion in eggs". Some teratogenio efforts Iiavo boon noted". Effects of DDT, DDE and PCB on hepotio entymes whioh incroase tho metabolism of progesterone, testosterone nd oestradiol havo also been pnbhshrd'. It is worth noting that bald agios (HctHaulu* ieucocepholut), fed a diet containing DDT, had between 58-80 p.p.m. DDT and DDD in their brains when they dtod". Approximately tho tamo voluoo wore found in robins and house-sparrows11. Brain tissue in whito tailed eagles from tho Stockholm area oontainod on averago 100 p.p.m. (fresh tissue) of DDE. DDE, on the othor
Jioud, is less acutely toxic then DDT itsolf. The greatest value in North American bald eaglee oolleoted in tho fiold in 1005 was 118 p.pjn. (mainly DDE) in musole tissues". Tho greatest level for sampled wild whito tailed eagles from Swoden is 400 p.p.m. (mainly DDE) and tho mean
was 930 p.p.m. in musclo tissue (wet weight). Nothing is yot known about the PCB content in bald eagles from North America, but in eagles from our arohipelago the mean valuo in musole was 190 p.p.m. (brain 47 p.p.m.)
and tho greatest figure was 240 p.p.m. (brain 70
p.p.m.). Neither the fresh tissue nor tho original fat values were
estimated in the addled eggs from white tailed eagles. Sometimes tho water oontent was aa low as 8 per oent
(normally 70-75 per eent in fresh hen eggs). The values based on tho fat oontent of theeo eggs ore probably more
reliable and we only report such figures. Tho levels, although high, were only 1/25 of tiioso of tho oaglo fat. Tho residues of DDT and PCB in tho guillemot eggs woro about 50 por cent lowor titan thoeo in the whito tailod oaglo oggs. The guillomota are vagrant In winter but most
of tho oontral Baltic population is beliovod to remain in tho Baltic area the year round. It is not known whother tho population is decreasing, but no drastio decline has
been reported. All species mentioned here (exoept mussel) are more or
loss vagrant, thereby giving a pioture of the situation in a large water aroa. A relatively few analyses on a vagrant animal may not give a very aocurate pioture, but when different sj>ecies are shown to oontain more residues in the Baltio than in the North 8ea and the Atlantio, the
situation is more convincing. In the Baltic proper, the Gulf of Bothnia and in tho
archipelago of Stockholm, tho levels of chlorinated hydro carbons are approximately ten tiroes greater than the reported sparse figures for comparable spooies in tho North Son area and the Atlantio. This may be caused by several factors. The Baltio is surrounded by largo areas of land and ths water volume Is comparatively small. Further
more, the water sotohange with the North Sea is very limited ss a oonsequsnoe of the thresholds (18 and 8 ra deep) and the narrowness of the Danish sounds. Residues brought into the Baltio from the ooasts and from air pollution will accumulate here to a great extent. This dovolopmont is no doubt favoured by a gonerally low
niicrobioliigicnl activity
of very Inn ). ii.p.
of tlu> inlormtdiAle Boltin "winter wto.-r" dining
tho year, and nlwi of (lie deep water layer* m tin. noihtm
nri'Oit. As iv onnwHtntNro el the tillin'. .1.1 w.nt.,
thin i'k iiIho largely true lei the upper Nuii.it . Inyi-r.
'i
Tho brackish water diameter of tint Hull to nL.i fuvenr, a oonoentmtion of rtwitluos in living nrgeniKinH. Tl
sulietancos in rptnslion are preltaltly more moldy iratu ported in a horizontal direction by living nnti nr from
water to tho low milinity surfaoo vvatir (lii-<|tt*-ntjy .y_j por millo or loss) of tho archipelagos and at-am tin lln|lw
coasts, In tho North Sou, tlio disorepancy Ix-iwoen thf
salt soawaU'r nnd IivhIi water especially lirn conibineit ' with tho effect of tho tidal movementh cm result in ,
faster decomposition of froshwutor organism-t and of organic matter, including the ob)r>rir>ole,l hydrocarbons.
Tho Inoronaod atui more inumxlinto contort hero with tho
microbiological activity located In the bottom material
may be important. Furthermore, thorn ih in thn lisluc
proper a pronounoed stratification of tho water. A dmtmc.
halocline dolimits tho doep water of higher .salinity p
wards (usually in 60-70 m depth). In the warm nesson.
tho uppermost surfaco layer ia sopnroted from tho "winm
water*'by a very marked thormoclirm (usually in Ir>-2rj rr.
depth, somotimes supported by a snuimilnry hukrcluo. .
As a result of thoeo two ilisoontinuity layer* ami, cap*,, ally in coHtnl areas, of tho obwiicu <>f marU< .1 mi .
currents, tho vortical water oxrhnngo and movern- i.-.
aro more or leas blocked. Tho contact of sinking organ -
matter with tho bottom material ia thim to a grrnt ext*:.-,
delayed. In the discontinuity layors of the Bultic S'f.i,
living and dead plankton and othor organic matter art
oonoontrated, as a ooneoqucnco of differences in tU t
speoifio gravity of the water. Tho laycre mrntionrd ar.
important feeding areas for plankton nnd pelagic fish tuch
as herring and sprat. In tho Sound, in the archipelago of
Stockholm' and in the Idefjord, local sources of pollution
oan bo Important us tho rosiduo lovels indicato.
We thank Mrs Keratin Widinork, Mr Bruno Nucci, Mrs
Elsa Nucoi, Miss Gunnol Blomkvist and Miss Margarets Ostberg at the Institute of Analytical Chemistry, ths
University of Stockholm. We also thank Mr Weraar
Berg and Mr Bengt Wallin at the Museum of Natural I
History, Stockholm, for their help in this work.
Beceivtf May It, !M.
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