BSEP116B Biodiversity in the Baltic Sea - Helcom

Heavy metals
Heavy metals, such as mercury and cadmium
which are specifically addressed by the BSAP, are
widely used in industrial products and processes.
As an example, mercury is extensively used in the
chlor-alkali industry and cadmium in metal industries.
Significant amounts of atmospherically transported
heavy metals originate from distant sources outside
the Baltic Sea catchment area. For cadmium, lead
and mercury, the proportion of distant sources
located outside the HELCOM area was larger than
half of the total emissions in 1996–2000 (HELCOM
2005b). A large part of the waterborne inputs of
heavy metals also originates from non-HELCOM
countries in the catchment area (HELCOM 2007f).
For cadmium, lead and mercury, non-HELCOM
countries accounted for 5% to 13% of total riverine
transboundary inputs (HELCOM 2007f).
Annual emissions of heavy metals from HELCOM
countries to air have decreased during the period
from 1990 to 2006 by 47% for cadmium, 45% for
mercury, and 86% for lead (Gusev 2008a) (Figure
6.6.1). Since the mid-1990s, riverine heavy metal
loads, especially those of cadmium and lead, have
also decreased in several countries (Knuuttila in
prep.).
The total atmospheric deposition of heavy metals
into the Baltic Sea during 2006 was 7.1 tonnes of
cadmium, 3.4 tonnes of mercury and about 234
tonnes of lead (Gusev 2008b). The Belt Sea and
Kattegat were the sub-basins receiving the highest
amounts of heavy metal deposition. The reported
waterborne loads to the Baltic Sea in 2006
amounted to 47.5 tonnes of cadmium, 10.8 tonnes
of mercury and 274.2 tonnes of lead (Knuuttila in
prep.).
Organic pollutants
The main source or pathway to the Baltic marine
environment of tributyltin (TBT) and triphenyltin
(TPhT) is their use as anti-foulants on ship hulls
and subsequent direct release to seawater. On
the other hand, the main pathways of pentabromodiphenyl
ether (pentaBDE), octabromodiphenyl
ether (octaBDE) and decabromodiphenyl ether
(decaBDE), hexabromocyclododecane (HBCDD),
perfluorooctane sulfonate (PFOS), perfluoroocta-
HELCOM countries emissions,% of 1990
120
100
80
60
40
20
0
1990
1991
Cadmium Lead Mercury
1992
1993
1994
1995
1996
1997
1998
Figure 6.6.1. Total annual emissions (as % of 1990 emissions) of
cadmium (Cd), mercury (Hg), and lead (Pb) to air from HELCOM
countries in 1990–2006 (Gusev 2008a).
noic acid (PFOA), short-chain chlorinated paraffins
(SCCP), and medium-chain chlorinated paraffins
(MCCP) to the Baltic Sea are via municipal
and industrial wastewaters and the atmosphere.
Municipal and industrial wastewaters are also the
main sources of nonylphenols (NP), nonylphenol
ethoxylates (NPE), octylphenols (OP), and octylphenol
ethoxylates (OPE). The main pathways
of endosulfan are via rivers receiving losses from
agricultural land and from atmospheric deposition
due to the application of agricultural pesticides
containing endosulfan. Discharges from landfills
and via storm water can be significant for some of
the substances mentioned above (HELCOM 2007a,
2007g, HELCOM 2009b).
The net annual atmospheric deposition of polychlorinated
dibenzo-p-dioxins/polychlorinated
dibenzofurans (PCDD/Fs) to the surface of the
Baltic Sea has decreased by 59% during the period
1990–2006. At the sub-basin level, the most significant
decrease in PCDD/F deposition has been
observed in the Belt Sea (73%) and Kattegat
(65%). Currently, the highest levels of PCDD/F
deposition over the Baltic Sea have been observed
for the Belt Sea and the lowest deposition fluxes
for the Gulf of Bothnia (Gusev 2008c).
6.6.2 Occurrence and impacts of
hazardous substances on Baltic
biodiversity
For many organic contaminants, a full assessment
of their levels and effects in Baltic marine biota is
not possible owing to the lack of monitoring and
ecotoxicological data.
1999
2000
2001
2002
2003
2004
2005
2006
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