Övervakning av metaller och organiska miljögifter i marin biota, 2012

• The environmental toxicants examined in this report can be classified into five groups –heavy metals, chlorinated compounds, brominated flame retardants, polyaromatichydrocarbons and perfluorinated compounds. Each of these contaminants has beenexamined from various sites for up to six different fish species, in blue mussels, and inguillemot eggs, for varying lengths of time. The following summary examines overalltrends, spatial and temporal, for the five groups.Condition and Fat ContentCondition and fat content in different species tended to follow the same pattern at the samesites, with a few exceptions. Most of the fish species generally displayed a decreasing trendin both condition and fat content at most sites examined. Exceptions to this were increasesin fat content and condition factor seen in cod liver at both sites; an increase in conditionfor herring at Ängskärsklubb in spring; and in perch and eelpout, a decrease in fat content atKvädöfjärden (perch) and Väderöarna (eelpout) but no trend in condition for the same site.Heavy MetalsDue to a change in methods for metal analysis (not Hg) in 2004, values between 2003 and2007 should be interpreted with care. From 2009 metals are analyzed at ITM, StockholmUniversity.The longer time series in guillemot egg and spring-caught herring from the southernBothnian Sea and southern Baltic Proper show significant decreases of mercury. Theherring site in the southern Bothnain Sea indicates a local Hg-source. The rest of the timeseries show varying concentrations over the study period, and even increasing trends in e.g.cod muscle and eelpout muscle from Väderöarna, but the concentrations are fairly lowcompared to measured concentrations in perch from fresh water and coastal sites. However,in most cases, these concentrations are above the newly suggested EU-target level of 20ng/g wet weight.Lead is generally decreasing over the study period (in time series of sufficient length),supposedly due to the elimination of lead in gasoline. Elevated lead concentrationsbetween 2003 and 2007 (e.g. Harufjärden) should be viewed with caution (see aboveregarding change in analysis methods).Cadmium concentrations show varying non-linear trends over the monitored period. It isworth noting that despite several measures taken to reduce discharges of cadmium,generally the most recent concentrations are similar to concentrations measured 30 yearsago in the longer time series.The reported nickel concentrations show no consistent decreasing trends. Some series beginwith two elevated values that exert a strong leverage effect on the regression line and maygive a false impression of decreasing trends. Chromium generally shows decreasing trends,possibly explained by a shift in analytical method. The essential trace metals, copper andzinc, show no consistent trends during the monitored period.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Environmental Sciences (hsv//eng)

Nyckelord

Nationellt finansierad miljöövervakning

National

Kust och hav

Coast and sea

Metaller och organiska miljögifter i biologiskt material

Metaller och organiska miljögifter i biologiskt material

Hav i balans samt levande kust och skärgård

A Balanced Marine Environ­ment, Flourishing Coastal Areas and Archipelagos

A Non-Toxic Environment

Giftfri miljö

Publikations- och innehållstyp

vet (ämneskategori)

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