Bull. Environm. Contam. Toxicol. 20, 715-720 (1978)

Organochlorines in Codfish From Harbours Along the Norwegian Coast E. M. Brevik, J. E. Bjerk, and N. J. Kveseth Veterinary College of Norway, Department of Pharmacology and Toxicology, Oslo, Norway

Levels of P C B s , H C B , a n d s u m - D D T in l i v e r f r o m c o d fish caught near major harbours along the coast of Norway were determined. Samples consisted mainly of w h i t i n g (Merlangus merlangus) and codling (Gadus morhua) from the southern and northern part of the coast,respectively. These species of codfish are present all along the coast and are considered to be s t a t i o n a r y . They have livers r i c h in fat, a n d a r e h e n c e suitable for monitoring organochlorines. The purpose o f t h i s s u r v e y w a s to s e e if any of the selected harbours were especially contaminated. Results were also compared with those from a previous survey on organochlorines in c o d l i v e r s from south western waters (KVESETH and BJERK 1976, BJERK 1973). MATERIALS

AND

METHODS

The sampling sites (Fig.l) were selected according to t h e i r i n d u s t r i a l structure, geographical location, and number of inhabitants. In J u n e 1 9 7 6 , a b o u t i0 c o d f i s h were caught at e a c h of the sampling sites. From Bergen, however, only three fish were obtained, and such a small number of s a m p l e s may not give a representative contamination picture for the area. The Bergen results should thus be regarded as being indicative only. all 1.3

The codfish weights varied between 0.i and 0.6 the localities except Mo where the mean weight kg.

kg for was

The fish were wrapped in a l u m i n u m foil and stored in a f r o z e n state until dispatched to t h e l a b o r a t o r y eith e r b y t r a i n o r air. A t t h e l a b o r a t o r y , the samples were stored at - 2 0 ~ until analyses could be carried out. Together with the samples, the laboratory information about the sampling sites including cription of industries in t h e v i c i n i t y .

received a des-

Analyses were carried out according to a m e t h o d described elsewhere (BJERK and SUNDBY 1970). The lipids were extracted with diethyl ether, and divided into two parts which were then treated with conc.sulphuric acid and potassium hydroxide in m e t h a n o l , respectively. The ~-hexane extracts obtained were analysed by gas liquid

0007-4861/78/0020-0715 $01.20 9 1978 Springer-Verlag New York Inc.

chromatography on t w o c o l u m n s , 4 p e r c e n t S F - 9 6 a n d I0 p e r c e n t Q F - 1 on C h r o m o s o r b W, 1 0 0 / 1 2 0 m e s h , r e s p e c t i v e l y . Wilcoxon's matched p a i r t e s t w a s u s e d in t h e s t a t i s t i c a l processing of t h e n u m e r i c a l d a t a ( H ~ Y L A N D and W A L L ~ E 1975). RESULTS The samples consisted m a i n l y of w h i t i n g from sampl i n g s i t e s in t h e s o u t h a n d c o d l i n g f r o m t h e n o r t h . A t three localities, saithe (Pollachius virens) and pollack (Pollachius pollachius) were caugt together with either c o d l i n g or w h i t i n g . As a n a l y s e s showed only small variat i o n s in l e v e l s b e t w e e n species from the same sampling s i t e , no r e g a r d is g i v e n to s p e c i e s i d e n t i f i c a t i o n in T a b l e 1 a n d F i g . l w h e r e all v a l u e s are s h o w n . T h e v a l u e s discussed in the p r e s e n t p a p e r are t h e m e a n l e v e l s c a l c u l a t e d on a w e t w e i g h t b a s i s . T h e s e , a n d t h e c o r r e s p o n d i n g fat per centages, a r e g i v e n in T a b l e i. TABLE P C B s , HCB, in N o r w a y .

and

sum-DDT

Nr.

Locality

N

i. 2. 3. 4. 5. 6. 7. 8. 9. I0. Ii. 12. 13. 14. 15. 16.

Fredrikstad Moss Dr~bak Oslo Larvik Kristiansand Lista(Farsund) Stavanger Bergen Molde ~ndalsnes Trondheim Mo Narvik Troms~ Vard~

13 23 i0 5 12 i0 9 12 3 9 l0 I0 6 8 i0 i0

I

in c o d f i s h

(liver)

from

Extr. L e v e l s in p p m , w e t (arithemetic mean fat % sum-DDT PCBs 35+12 0.5+0.3 4.8+2.2 40~15 0.8~0.9 2.7~2.5 53+13 1.9+1.0 7.5+6.4 50~iI 0.5~0.2 3.3~i.0 29+16 0.6+0.4 1.4+0.7 44~14 0.i~0.I 0.8~0.5 22~15 0.2~0.2 0.7~0.5 40~ii 0.3+0.2 1.0~0.6 51~ 5 14.5~4.7 5.9~1.6 20~14 0.2~0.1 2.4~0.8 39~I0 0.5~0.2 1.0~0.6 54~13 0.6~0.i 1.9~0.8 44+ 7 1.2+0.8 1.8+1.0 36~ 8 0.2~0.I i.9~0.6 25~14 0.3~0.2 1.6~I.0 34+ 7 0.2~0.I 0.8~0.3

harbours

w e i g h t basis + S.D.) HCB 0.73+0.44 0.07~0.06 0.24+0.06 0.14~0.05 0.08+0.07 2.29~1.78 0.02~0.03 0.04~0.02 0.06~0.01 0.02~0.02 0.04~0.01 0.08~0.04 0.05+0.01 0.02~0.01 0.02~0.02 0.06~0.02

s u m - D D T : The s u m - D D T in cod l i v e r f r o m B e r g e n (14.5 ppm) was w e l l a b o v e the l e v e l s f o u n d at the o t h e r s a m p l i n g sites. I n the O s l o f j o r d a r e a D r @ b a k (1.9 ppm) h a d a s i g n i f i c a n t l y higher (P~0.05) l e v e l t h a n O s l o a n d F r e d r i k s t a d . Results from the s a m p l i n g s i t e s f u r t h e r n o r t h i n d i c a t e a r e l a t i v e l y high l e v e l at Mo, b u t no s i g n i f i c a n t difference was found between this town and Trondheim and A n d a l s n e s . D D T w a s f o u n d in l i v e r t i s s u e s f r o m the d i f f e r e n t s a m p l i n g sites, e x c l u d i n g Bergen and D r ~ b a k , in c o n c e n t r a t i o n s b e t w e Q n I.i and 0.i ppm. 716

0

100

k

I

200 |

3 0 0 km I

F/J '

f ~Q"

B

-15

/ i

10

! A,~ODT B,

I.ICB

C : PCBs 5

ARC 1_...._

ppm

Fig.l.

Levels of sum-DDT, H C B , a n d P C B s in c o d f i s h (liver) from major harbours situated along the coast of Norway. The localities are numbered and the names a r e g i v e n in T a b l e i. T h e h i s t o g r a m s represent meaI levels calculated on a wet weight basis.

HCB: There were significant differences (P&0.05) in t h e lev e l s f o u n d at s o m e of t h e d i f f e r e n t localities, a n d t h e fo] lowing sequence o f levels w a s i n d i c a t e d : Kristiansand: 2.3 Fredrikstad: 0.73 > Dr~bak: 0.24 9 others: l e s s t h a n 0 . 1 5 pp~ HCB. PCBs:The results indicate that the concentration o f P C B s iz liver tissues was higher at B e r g e n a n d in t h e O s l o f j o r d a r e a , t h a n in t h e r e s t o f t h e s a m p l i n g material. The level

717

at Bergen was 5.9 ppm PCBs. In the Oslo fjord area, no consistent gradient of levels was found when moving from the head to the mouth of the fjord. This is i l l u s t r a t e d by the following levels: Oslo: 3.3, Dr~bak: 7.5, Moss: 2.7, and Fredrikstad: 4.8 ppm. Concerning between 2.4 ppm

the other localities, the (Molde) and 0.7 ppm (Lista)

levels .

varied

DISCUSSION While DDT has been exclusively used as an insecticide, the PCBs have had a widespread industrial use, especially in electroand chemical industries. HCB has been used as a fungicide, although not in Norway. QUINLIVAN et al. (1977) have reviewed it's use in industrial processes and they state that the main source of contamination by this compound is a s s u m e d to be due to it's synthesis as an industrial byproduct. The intention was to collect fish samples from the main harbours in a selected number of towns along the Norwegian coast. At Mo, Dr~bak and Fredrikstad,however, the sampling site was 2-3 km from the commercial harbour, while at Bergen the site was located 5 km from the harhour near to a suburb. sum-DDT: In the Oslo fjord area, a relatively high level of sum-DDT was found in whiting (liver) caught just south of Dr~bak. This locality was rather close to the mouth of the Drammens fjord, and the relative high level of sumDDT, HCB and PCBs (Tab.l) , may represent the sum of contamination from both the Oslo - and the Drammens fjord. The area north of Drammen is a t y p i c a l fruit growing district, but as the distance to Dr~bak is a b o u t 30 k m , a n d the contamination due to the fruit growing is k n o w n to be rather local (BJERK 1973) , the prior use of DDT in this district is n o t considered to be the source of the present level at Dr~bak. Concerning the northern part of the country, there seems to be a local high level of contamination at Mo, though this level was not significantly different from the levels found at Trondheim and ~ndalsnes. The fjords in the south western part of Norway have previously been monitored for sum-DDT residues. (BJERK 1973, KVESETH and BJERK 1976) . The background level in cod liver from Eivindvik was 1.8 ppm sum-DDT in 1971 (BJERK 1973) . Further north at Lofoten, the mean level in liver from seven cod (mean weight 5.0 kg) caught in 1976, was i. 1 + 0 . 5 p p m sum-DDT (unpublished data) . In 1972, good correlation was found between sum-DDT in cod liver and the amount of fruit growing in the surrounding districts (KVESETB and BJERK 1976) . Prior to the ban on the use of DDT in 1970, this insecticide had a widespread use. In t h e p r e s e n t study, all localities except Bergen showed levels similar to the "no fruit growing" group

718

(1.3+1.0 ppm sum-DDT) of 1972. The high levels found in the Bergen material, would have put this location in the "major fruit growing" group (16.3+9.0 ppm sum-DDT) of 1972, although no commercial fruit growing takens place at this locality. PCBs: The results indicate that levels were higher at Bergen and in the Oslo fjord area, than at the other sampling sites. The mean level at Bergen was 5.9 ppm PCBs and in the Oslo fjord area levels varied between 2.7 and 7.5 ppm PCBs. As for the Oslo fjord area, such a contamination picture could be expected, since the largest and most diversified industries in Norway are located in this district. The present data,however,does not seem to allow the further pinpointing of sources of contamination. Concerning the samples from Bergen, no explanation can be given for the high level found. Local "industrial" activities which may influence PCB-levels in fish,comprise a nearby Navy base and a yacht harbour, since PCBs have been used in boat bottom paints (Jensen et ai.1972) . As regards the other localities, special mention may be made of Molde and the nearby Andalsnes, as the respective levels found at these two sites differed significantly (P~0.01) . This could indicate a local contamination at Molde, but compared with most of the localities further north, no such difference could be seen between the levels at Molde and for example those at Mo and Narvik. Consequently, there seems to be no reason to further discuss the minor differences between these localities. On the basis of the data given by KVESETH and BJERK (1976), one can Conclude that cod from uncontaminated fjord areas in t h e s o u t h western part of Norway contain 1.6+1.1 ppm PCBs in their livers. The mean level in liver from seven cod (mean weight 5.0 kg) caught further north at Lofoten in 1976, was 1.0+0.6 ppm PCBs (unpublished data)~ Comparison of this data with the present results, showed that the sampling sites which appeared to be especially contaminated were the Oslo fjord area and Bergen. HCB: Since H C B is r e p o r t e d to be generated as a waste product in the manufacture of a number of chemicals and metals (QUINLIVAN et ai.1977) , the highest levels would be expected in the Oslo fjord area for the same reason as given for PCBs. The present study supports this assumption, as the mean level in codfish liver from the Oslo fjord area was seven times higher than the mean level for the other localities (excluding Kristiansand) 0.30 and 0.04 ppm HCB,respectively. The highest level was found in codfish (liver) from Kristiansand, followed by Fredrikstad, Dr~bak and Oslo. Levels at the remaining sites were below 0.i0 ppm HCB and are assumed to reflect the general contamination level in codfish (liver) from the harbours along the coast of Norwa~ Since this is t h e f i r s t report including HCB in the monito-

719

ring programme, at the moment.

it

is

impossible

to

discuss

any

trends

Fredrikstad is l o c a t e d at t h e e s t u a r y of G l o m m a , the largest r i v e r in N o r w a y . The district around the navigable 15 k m of t h e r i v e r is h e a v i l y industrialized and includes t w o t o w n s . T h e l e v e l o f 0 . 7 3 p p m H C B in c o d f i s h liver from theharbour of Fredrikstad was about ten times higher t h a n at t h e n e a r b y industrial t o w n of M o s s , i n d i cating a local contamination at t h e f o r m e r h a r b o u r . Kristiansand has a considerable metallurgic industry a n d is t h e l a r g e s t t o w n in t h e s o u t h e r n part of Norway. The present investigation revealed a relatively high level at t h i s l o c a t i o n , 2.3 ppm HCB. The present degree of contamination was of the same order of magnitude as t h a t f o u n d in c o d f i s h from the same harbour in 1 9 7 5 (BREVIK in p r e s s ) . These investigations indicate that the harbour of Kristiansand has been relatively heavily contaminated with HCB for several years. T h e l e v e l w a s of t h e s a m e o r der of magnitude as t h a t r e p o r t e d for cod (muscle) from the Frierfjord,Porsgrunn, during the period f r o m 1 9 7 2 to 1975 ( B ~ C K M A N et a i . 1 9 7 6 ) . CONCLUSIONS L e v e l s of P C B s , H C B a n d s u m - D D T f o u n d in c o d f i s h liver obtained near the harbours of s e v e r a l towns located a l o n g t h e c o a s t of N o r w a y , are generally low. The degree of contamination appeared to b e s o m e w h a t higher in t h e O s l o f j o r d a r e a t h a n at t h e o t h e r s a m p l i n g sites. Except i o n s to t h i s g e n e r a l picture were Bergen (high levels of sum-DDT and PCBs) and Kristiansand harbour (high lev e l s of H C B ) . REFERENCES BJERK,J.E.

,and

BJERK,J.E.

: Bull. Environ. Contam.Toxicol.9,89

BREVIK,E.M.

:

R.SUNDBY:

(In

Nor.Vet.-Tidsskr.82

,241

(1970)

(1973)

press)

B~CKMAN,O.C. , J.A.CROWO, S.T.FALCK and J.G.JOHANSEN: Organiske miljCgifter i vatten. 12.Nordiske symp.Visby, Sweden,1976 H~YLAND,A.and L.WALL~E: og b i o l o g i s t u d e n t e r . T a p i r JENSEN,S.,

L.RENBERG

KVESETH,N.J.and QUINLIVAN,S.C. ous Materials

Statistikk for medisin-, farmasitrykk,Trondheim,Norway,1975

and

J.E.BJERK:

M.OLSSON: Nord.Vet.

, M.GHASSEMI and i, 3 4 3 ( 1 9 7 7 )

720

Nature

240,358

Med.28,170

T.V.LESHENDOK:

(1972)

(1976) J.Hazard-