Anna Brzezińska, Teresa Bogacka, Regina Taylor, Anna Trzosińska

OCEANOLOGY NO 11 (1979)
85
ANNA BRZEZIŃSKA
TERESA BOGACKA
REGINA TAYLOR
A N N A TRZOSINSKA
Institute of M eteorology and W ater M anagem ent
Marine Branch — Gdynia
INPUT OF MERCURY COMPOUNDS WITH THE VISTULA WATERS
C o n t e n t s : 1. Introduction. 2. M aterials and m ethods of investigations, 3. R esults
and discussion; Streszczenie; references.
1. INTRODUCTION
M ercury, particu larly in the form of organic compounds, is one of the
m ost hazardous com ponents of the aquatic environm ent, m ainly because
of its toxicity and progressing accum ulation in th e consecutive links of
the food-webs of aquatic organism s [8], According to bibliographic sources
[10, 16], the n atu ral level of m ercury in the m arine environm ent varies
from 0.01 to 0.1 m icrogram s per litre.
M an’s activities, m ostly th e increasing application of chem ical sub­
stances have given rise to a higher level of m ercury in the environm ent
[13], The principal sources of m ercury in th e hydrosphere are sewage
from the chem ical in d u stry (electrolytic production of chlorine), electrical,
cellulose, pharm aceutical, as w ell as other industries, and th e products of
coal and oil combustion. The p resen t pollution of some E uropean and
A m erican surface w aters am ounts to several m icrogram s of m ercury per
litre, while the am ounts of m ercury accum ulated in fish often exceed
those perm itted by the standards for purposes of consum ption (0.5 mg
per kg in the Anglosaxon countries and 1 mg per kg in Sweden); bottom
sedim ents a t the sewage outfalls can reach as m uch as hundreds of m illi­
gram s per kg [10],
So far, inform ation about th e m ercury contents in Polish surface
w aters is very lim ited [3, 4], This paper presents the first system atic
studies of the m ercury contents in the V istula w ater. The results obtained
give a certain insight into th e level as well as variation of m ercury con­
centrations in four cross-sections of the V istula during the years 1974
to 1976.
2. MATERIALS AND METHODS OF INVESTIGATIONS
W ater was taken from the V istula in the period from Septem ber
1974 through October 1976 in the following cross-sections:
K raków (Cracow)
— 69 km dow nstream from source
W arszawa (Warsaw) — 509 km dow nstream from source
K ieżm ark
— 926 km dow nstream from source
Świbno
— 941 km dow nstream from source.
The sam ples w ere taken once a week in the th ree first cross-sections
and th ree tim es a week in the Swibno cross-section, about 20 cm below
the surface. They w ere preserved w ith concentrated nitric acid [7] and
were stored at 0—4°C u n til the tim e of analysis. D uring the first year of
the study several series of d ifferent fish species w ere also sam pled from
the low er Vistula.
M ercury compounds in u n filtered w ater samples w ere determ ined by
cold vapour flam eless atom ic-absorption spectrophotom etry. The inorganic
m ercury compounds w ere determ ined directly, while the total m ercury
contents w ere found afte r m ineralization at room tem p eratu re w ith a
concentrated nitric and sulphuric acids, potassium perm anganate solution
an d potassium persulphate solution [1— 3], The reagents w ere commercial
m ercury-free or w ere purified in the laboratory. Blanks w ere determ ined
in each case. M ercury concentrations w ere m easured by m eans of a
P erkin-E lm er Coleman MAS-50 analyser or Beckm an atom ic-absorption
spectrophotom eter, model 1272. The detection lim it calculated for both
instrum ents as the standard deviation of ten m easurem ents in the re­
agents taken as a blank was respectively 10 ng and 2 ng for total m ercury
and 5 ng and 1 ng for inorganic m ercury. The precision of the m easure­
m ents was evaluated from separate series of ten determ inations in the
V istula w aters w ith different m ercury concentrations. The coefficient of
variation, com puted for the 0.95 confidence level was 5 to 10 per cent
for concentrations range of 0.1— 1 ixg Hg/1 and approached 50 per cent
for concentrations around the detection limit. The accuracy of the m eas­
urem ents was found from m ercury determ inations in seven samples
used as references at the U.S. Envirom ental Protection Agency laboratories.
In all cases the relative erro r did not exceed 5 per cent.
The same procedures and equipm ent w ere used for determ ination
of total m ercury in fish. The m ean sample of the whole fish body was
hot-m ineralized using a m ixture of nitric and sulphuric acids w ith the
addition of hydrogen peroxide, and processed by the Jeffus m ethod [11].
T he results w ere calculated for the w et mass.
3. RESULTS AND DISCUSSION
In the period of 1974— 1976 the concentration of total m ercury in the
cross-sections of the V istula River varied from 0.09 to 5.60 ng p er litre.
The m ean concentrations w ere 1.01, 0.89, 0.83 and 0.85 ixg per litre for
th e upper, central, lower and estu ary cross-sections respectively. The
average concentrations decreased w ith th e distance from the riv e r’s
source. The decrease was small, how ever, so th e statistical analysis has
not indicated any essential differences in m ercury contents a t th e various
cross-sections (Table 1). The average concentrations in the upper (Cracow)
an d low er V istula (K ieżm ark and Swibno) w ere five to six tim es lower
th a n those perm itted for the p u rity class II w aters, assum ed for the riv er
Table 1
Tabela
1
Statistical evaluation of m ercury concentration (¡xg/1) in the Vistula, 1974 to 1976
Statystyczna ocena w yników pom iarów stężeń rtęci (ng/1) w wodach W isły w la ­
tach 1974—1976
Concentration
w eighted
m ean
R iver cross-section
and m ercury form
Number
of sam ples
Przekrój rzeki i
form a rtęci
Liczba
prób
X
Stężenie
średnie
w ażone
X
Kraków (Cracow)
total m ercury
inorganic m ercury
79
79
1.02
0.31
organic m ercury
79
0.68
74
74
74
W arszawa (Warsaw)
total m ercury
inorganic m ercury
organic mercury
Kieżmark
total m ercury
inorganic m ercury
organic m ercury
Swibno
total m ercury
inorganic m ercury
organic m ercury
m odal or
(most
frequent)*
m odalne
lub (naj­
częściej
w ystęp u ­
jące)*
Standard
deviation
°x
Percent of
data in the
rangę
x ± °x
O dchylenie Liczba da­
standar­
nych w za­
kresie
dow e
x ±
°x
1)1
/o
0.57
0.28
/ 0.30 \
\ 0.70 /
0.74
0.30
80
95
0.69
91
0.89
0.28
0.60
0.63
0.24
0.36
0.59
0.30
0.57
85
96
92
90
90
90
0.83
0.28
0.57
0.64
0.29
0.37
0.48
0.28
0.42
77
100
83
216
216
0.84
0.42
0.71
0.55
87
72
216
0.42
0.77
0.13
/M0\
\0.50 /
0.33
92
» V a rian ts of tw o m ost n u m ero u s classes.
W arian ty dw óch n a jlicz n ie jsz y ch klas.
Fig. 1. Histogram s of total m ercury concentration in the V istula in the years 1974
through 1976 (the broken line denotes the w eighted m ean, the solid line — the
perm issible concentration along the given river section)
Rye. 1. Histogram stężeń rtęci całkow itej w W iśle w latach 1974—1976 (linią przery­
w aną zaznaczono w artość średnią, linią ciągłą — stężenie dopuszczalne na danym
odcinku rzeki)
sections studied (Fig. 1). The predom inant concentrations w ere seven to
ten tim es low er th a n the quantities accepted by Polish standards *. The
m ean concentration of total m ercury in the V istula River a t W arszawa
(Warsaw) was slightly low er th a n th a t perm issible for th e class I w aters,
th a t this section belongs to. The m ost freq u en t concentrations w ere lower
th a n the perm issible by a factor of alm ost two.
High, m ercury concentrations, of up to 5 M-g per litre, have been
noted in the V istula R iver occasionally. They w ere m ostly due to organic
compounds in the upper and m iddle V istula while the ionic form prevailed
* Rozp. Rady Min. of 29th Novem ber 1975, Dziennik U staw 41 of 13th Decem ber 1975,
par. 214 and Zarz. Prez. CUGW of 15th February 1972, Monitor P olski 15/1972.
Fig. 2. Histogram s of organic m ercury concentration in the V istula in the years 1974
through 1976 (the broken lin e denotes the w eighted mean)
Rys. 2. Histogram stężeń organicznych zw iązków rtęci w W iśle w latach 1974— 1076
(linią przerywaną zaznaczono w artość średnią)
in the estuary (Figs 2 an d 3). These outbreaks w ere short-lasting and
th eir instantaneous character can be observed in m easurm ent results
carried out daily a t the Swibno cross-section (Fig. 4). It should be taken
into account th a t m ercury was determ ined in w ater samples containing
suspended m atter. From bibliographical sources [18] and our studies [9] on
0 020406OS10
0 020406OS10
0 020406
0 0204OSOS10121416162022242628JO 3234/g/yt
Fig. 3. Histogram s o£ inorganic m ercury concentration in the V istula in the years
1974 through 1976 (the broken lin e denotes the w eighted mean)
Rye. 3. Histogram stężeń nieorganicznych form rtęci w W iśle w latach 1974—1976
(linią przerywaną zaznaczono wartość średnią)
the m ercury contents in estuarine w aters it follows th a t the quantities ab­
sorbed on the suspended m a tter can v ary from several to about fo rty per
cent.
The present average level of m ercury in the V istula R iver does not
seem to endanger the aquatic ecosystems. However, the tw o-year research
does not enable long-term tren d s to be defined, so th a t continuous m oni­
toring of m ercury contents in the V istula is necessary, especially along
the sections which constitute sources of w ater supply for hum an con­
sumption.
Fig. 4. D aily fluctuations in m ercury concentration and flo w rate at the V istula
m outh during the period 15th March through 31st May, 1975
Rye. 4. Codzienne zm iany stężenia zw iązków rtęci w wodach ujściow ych W isły w
okresie od 15 m arca do 31 m aja 1975
The average am ount of organie m ercury compounds was about 70
per cent of the to tal m ercury in all riv er sections, except the estuarine
section, w here a decrease to about 55 per cent was found (Table 2). The
m easurem ents conducted sim ultaneously in the Gulf of Gdańsk [9] show­
ed th a t the ratio of organic-to-inorganic m ercury was about 1 : 1. A sys­
tem atic decrease of m ean organic m ercury concentrations tow ards the
m outh of the riv er was also noted (Table 1, Fig. 2).
From the analysis of m ean loads of total m ercury transported into
the sea daily (Table 2) one is unable to find a reg u lar relationship w ith
flow ra te and tim e of year, this featu re being characteristic for m icro­
com ponents of riv er runoff p articu larly for those which depend strongly
Tabela 2
Mean concentrations and daily loads of m ercury compounds in the V istula
Średnie stężenie i ładunki dobowe zw iązków rtęci w W iśle
Total *
Inorga­ Orga­
Total
m ercu- Total
nic
nie Flow ry load
Year m er­
m er­
m ercury m erraxe
kg/day cury
and
cury
¡xgHg/1
cury
m 3/s
month HgHg/1
i'-gHg/l
Ładu­
%
Rtęć
Rok i Rtęć
Prze­
nek *
Rtęć
Rtęć pływ
m ie­ całko­ nieor­
rtęci
całko­
ganicz­ orga­ m 3/s
siąc
całko­ w ita
w ita
niczna
na
w itej HgHg/1
(.igHg/1
HgHg/1
%
kg/doba
1
2
3
4
5
6
7
K r a k ó w (Cracow)
Inorga­ Orga­
nie
nic
Flow
m ercury m errate
¡xgHg/l
cury m 3/s
%
Rtęć
P rze­
nieor­
Rtęć
pływ
ganicz­ orga­
m 3/s
na
niczna
HgHg/1
%
8
9
Total *
m ercury load
kg/day
Ładu­
nek *
rtęci
całko­
w itej
kg/doba
10
11
W a r s z a w a (Warsaw)
1974
09.74
10
11
12
0.94
0.88
0.73
1.08
0.28
0.26
0.22
0.17
70.2
70.5
69.9
84.3
54
220
97
136
4.2
17.5
5.9
12.0
1.22
0.65
0.25
0.09
79.5
86.2
407
1778
41.5
101.2
0.75
0.15
80.0
1068
71.3
1975
01.75
02
03
04
05
06
07
08
09
10
11
12
2.87
1.54
1.19
1.43
1.81
0.55
0.85
0.59
0.65
0.55
0.40
0.58
0.51
0.47
0.49
0.34
0.58
0.17
0.57
0.17
0.31
0.26
0.18
0.22
82.2
69.5
58.8
76.2
67.9
69.1
32.9
71.2
52.3
52.7
55.0
62.1
172
61
68
179
79
126
135
115
74
79
72
97
37.3
8.0
6.3
15.3
12.2
5.7
6.9
6.3
4.2
9.7
2.6
5.6
2.41
1.36
1.15
0.81
0.72
0.94
0.69
0.65
0.68
0.47
0.38
0.45
0.53
0.41
0.43
0.26
0.29
0.31
0.26
0.23
0.33
0.23
0.18
0.20
78.0
69.9
62.6
67.9
59.7
67.0
62.3
64.6
51.5
51.1
52.6
55.6
1241
588
546
1037
650
781
837
784
463
594
449
420
283.0
66.8
53.8
81.5
42.5
64.9
47.2
44.5
28.5
25.8
14.8
17.5
1976
01.76
02
03
04
05
06
07
08
0.68
1.52
1.49
1.39
1.42
0.76
0.56
0.85
0.32
0.47
0.34
0.47
0.45
0.39
0.22
0.40
52.9
69.1
77.2
66.2
68.3
48.7
60.7
52.9
299
92
106
136
107
52
50
76
17.6
12.1
13.5
16.4
12.1
6.3
2.4
5.7
0.59
1.54
1.58
1.33
0.83
0.77
0.66
0.75
0.23
0.35
0.46
0.46
0.38
0.42
0.42
0.41
61.0
77.3
70.9
65.4
54.2
45.6
36.4
45.3
859
543
610
1470
610
835
385
302
24.7
72.1
83.2
168.4
43.4
58.3
16.8
19.4
1.01
0.30
70.3
103
9.5
0.89
0.28
68.5
739
59.4
w hole
period
1
2
3
4
5
6
7
8
Kiezmark
10
11
Św ibno
1974
10.74
11
12
0.51
0.51
0.63
0.10
0.08
0.16
80.4
84.3
58.7
2208
3420
2837
83.9
143.4
125.3
1975
01.74
02
03
04
05
06
07
08
09
10
11
12
1.95
1.38
0.84
0.66
1.01
0.70
0.64
0.66
0.65
0.46
0.37
0.34
0.49
0.46
0.46
0.24
0.43
0.10
0.21
0.28
0.34
0.19
0.24
0.24
74.9
66.7
45.2
63.6
57.4
85.7
82.8
57.6
47.7
58.7
35.1
29.4
2730
1615
1343
1668
1404
1270
1919
1406
766
720
803
735
372.4
192.6
96.6
113.9
120.7
78.7
78.3
76.4
42.5
29.2
26.0
26.7
1976
01.76
02
03
04
05
06
07
08
0.56
0.94
1.49
1.35
1.14
0.88
0.62
0.66
0.27
0.28
0.37
0.31
0.35
0.37
0.18
0.29
51.8
70.2
75.2
77.0
69.3
58.0
71.0
56.1
1435
1012
1285
2419
1112
1119
530
525
0.83
0.27
67.4
1444
whole
period
9
1.10
0.73
0.76
0.46
0.24
0.31
58.8
66.2
61.1
1265
1690
1398
120.5
99.7
88.9
0.70
0.77
1.05
2.40
0.64
2.12
0.66
0.39
0.62
1.86
0.25
1.25
5.5
40.0
42.2
22.5
62.8
43.3
1087
1289
809
687
805
790
62.9
82.0
72.1
150.8
44.8
143.0
67.6
63.1
165.7
275.8
113.0
81.4
27.9
29.6
0.35
0.78
0.19
0.39
0.57
0.47
0.15
0.44
0.08
0.09
0.11
0.07
54.7
47.1
60.8
62.7
79.8
80.6
1499
959
1298
2218
1111
1177
46.8
55.3
21.6
68.4
53.1
44.0
105.3
0.85
0.43
54.5
1201
80.8
» T he av erag e d a ily loads w ere co m p u ted using th e flow ra te s m ea su re d on th e days of w a te r
sam pling.
Ś red n ie ła d u n k i dobow e obliczono n a p odstaw ie p rzepływ ów w d n iac h pom iarów .
on hum an activities. The m onthly m ean daily load varied g reatly from
22 to 372 kg of m ercury. The m axim um values w ere rarely recorded,
usually in the w inter m onths, accompanied by extrem e high w ater levels.
Based on m easurem ents carried out in the period from M arch 1975
u n til the end of Ju n e 1976 a t K iezm ark and Swibno, th e total annual
input of m ercury (dissolved and particulate) into the G ulf of G dansk by
the V istula w aters was 29.6 an d 32.9 tons respectively. For comparison,
the annual m ercu ry discharge of the Rhine is assessed as 100 tons [17].
The m ean annual runoff of th e Rhine is 2.5 tim es th a t of the Vistula,
although the drainage area of the Raine is only 14 per cent greater.
7 — O ceanologia N r 11
Table
3
Tabela
3
M ercury contents in V istula fish
Zawartość rtęci w ciele ryb z W isły
Date
caught
Data
połowu
2.09.74
26.09.74
17.10.74
4.11.74
18.11.74
2.12.74
9.12.74
11.08.75
18.08.75
1.09.75
Fish species
Gatunek ryby
pike: Esox lucius
bream: A bram is bram a
roach: R u tilus rutilus
roach
roach
Eur. w hitefish: Coregonus albula
Eur. w hitefish
Eur. w hitefish
lam prey: P etrom yzon flu via tilis
V im ba vim ba
V im ba vim ba
carp: C yprin us carpio
bream
bream
bream
eel: A nguilla anguilla
bream
roach
roach
bream
bream
roach
bream
V im ba vim b a
Total
length of
fish, cm
C ałkowita
dł. ryby, cm
30
20
22
13
19
20
18
18
38
31
32
18
22
21.5
23.5
52
19
24
24
19
25
24
32
32.5
M ercury contents
m g/kg, w et w eight
Zawartość rtęci
m g/kg mokrej m asy
0.955
0.304
0.202
0.446
0.270
0.363
0.370
0.376
0.650
2.866
2.133
0.506
0.420
0.473
0.423
0.443
0.413
0.305
0.175
0.483
0.676
0.215
0.393
1.600
The data on m ercury in fish indicate th a t th e level depends on the
fish species, th e q u an tity increasing w ith th e age of the fish w ithin the
same species (Table 3). The highest m ercury level, of 2.8 mg p er kg, was
found in Vim ba vim ba, w hich feeds on th e benthic fauna. The direct
source of m ercury can thus be attrib u ted to bottom sediments. For other
fish species (bream , roach, E uropean w hitefish, lam prey, eel and pike) the
m ercury contents varied from 0.18 to 0.96 mg per kg and was 0.42 mg
per kg on average. The m ercury levels in fish caught in th e low est section
of the V istula w ere found to agree w ith those given in w orld data [6, 12,
15], although th e y sometimes exceeded the concentrations generally
accepted as critical for consum ption standards. It should be pointed out
th a t our analyses of the V istula fish w ere random ; m uch more on this
m a tter was done by N abrzyski and G ajew ska [14]. They found among
other things th a t the flesh of the fish caught in the lower V istula early
in the spring of 1972 contained relatively high am ounts of m ercury,
nam ely 0.48, 0.58 and 0.38 mg per kg for pike, bream , and Cyprinidae,
respectively.
Chodyniecki et al. [5] found th a t the m ercury levels of various fish
species caught in the G ulf of Pom erania and th e lower sections of the
Oder w ere low er and varied from 0.00 to 0.37 mg per kg. H erring and
cod displayed a tendency to accum ulate m ercury in the liver, w hile pike
— both in the liver and in the tissue. The highest contents w ere noted in
eel and pike.
The results of studies h ith erto point to the necessity for system atic
m onitoring of m ercury contents in the environm ent and fish of our
rivers, particularly th e Vistula.
ACKNOWLEDGEMENT
This study was perform ed at the In stitu te of M eteorology and W ater
M anagement, M arine Branch, Gdynia, and partially supported by the
U.S. Environm ental Protection Agency under the Project No PR.05-532-13.
OCEANOLOGIA N r 11 (1979)
96
A N NA BRZEZIŃSKA
TERESA BOGACKA
REGINA TAYLOR
A NNA TRZOSINSKA
Instytut M eteorologii i Gospodarki Wodnej
Oddział Morski — Gdynia
SPŁYW ZWIĄZKÓW RTĘCI Z WODAMI WISŁY
STRESZCZENIE
W pracy przedstaw iono w yniki dw uletnich (1974— 1976) system atycznych badań
nad zaw artością zw iązków rtęci w W iśle, na 69., 509., 926. i 941. km biegu rzeki.
Oznacźenia zostały w ykonane w dwóch różnych lobaratoriach techniką absorpcyjnej
spektrofotom etrii atom owej m etodą zim nych par, w niesączonych próbkach wody.
Dodatkowo uwzględniono ryby w yłow ion e w dolnej W iśle, analizując średnią próbkę
z całego ciała osobnika.
Stężenie rtęci całkow itej w w odzie w ynosiło średnio: 1.01 ¡j.g/1 w Krakowie,
0,89 ng/1 w W arszawie, 0,83 ug/1 w Kieżm arku i 0,85 (ig/1 w Swibnie. Przeciętna
zawartość organicznych zw iązków rtęci stanow iła około 70% całkow itej ilości tego
imetalu w e w szystkich przekrojach rzeki, z w yjątk iem odcinka przyujściow ego, gdzie
w ystąpił spadek do 55%. N ie stw ierdzono regularnych zm ian poziomu rtęci w W iśle
w zależności od sezonu i w ielkości przepływu. Na podstaw ie pom iarów w ykonanych na
w ysokości Kiezm arka i Sw ibna ocenia się, że ilość rtęci całkow itej, wnoszonej rocz­
n ie do Zatoki G dańskiej, jest rzędu 30 ton.
W yniki oznaczania rtęci całkow itej w rybach w skazują na zależność m iędzy
ilością zakum ulow anego m etalu a gatunkiem i w iek iem osobników. N ajw ięcej rtęci
zaw ierały certy, które odżyw iają się fauną bentosową. W innych gatunkach (leszcz,
płoć, sielaw a, minoga, w ęgorz .i szczupak) zaw artość rtęci m ieściła się w granicach
od 0,18 do 0,96 mg/kg.
W yniki pracy w skazują na konieczność w prow adzenia kontroli nad zaw artością
rtęci w W iśle.
REFERENCES
LITERATUR A
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