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Titolo:
MERCURY IN PRECIPITATION AND ITS RELATION TO BIOACCUMULATION IN FISH - A LITERATURE-REVIEW
Autore:
DOWNS SG; MACLEOD CL; LESTER JN;
Indirizzi:
UNIV LONDON IMPERIAL COLL SCI TECHNOL & MED,CTR ENVIRONM TECHNOL LONDON SW7 2PE ENGLAND
Titolo Testata:
Water, air and soil pollution
fascicolo: 1-2, volume: 108, anno: 1998,
pagine: 149 - 187
SICI:
0049-6979(1998)108:1-2<149:MIPAIR>2.0.ZU;2-4
Fonte:
ISI
Lingua:
ENG
Soggetto:
TROUT ONCORHYNCHUS-MYKISS; WALLEYE STIZOSTEDION-VITREUM; PRECAMBRIAN SHIELD LAKES; NORTHERN QUEBEC CANADA; FRESH-WATER ECOSYSTEMS; WABIGOON RIVER SYSTEM; PERCA-FLUVIATILIS L; PIKE ESOX-LUCIUS; EAST IRISH SEA; ATMOSPHERIC MERCURY;
Tipo documento:
Review
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
250
Recensione:
Indirizzi per estratti:
Citazione:
S.G. Downs et al., "MERCURY IN PRECIPITATION AND ITS RELATION TO BIOACCUMULATION IN FISH - A LITERATURE-REVIEW", Water, air and soil pollution, 108(1-2), 1998, pp. 149-187

Abstract

Increases in industrial mercury (HE) emissions in recent years have led many researchers to believe that Hg from the atmosphere constitutesa main source of Hg to aquatic biota in the absence of point source discharges. Established background levels for fish (0.2-1.0 mg kg(-1)) now exceed the pre industrial level of 0.15 mg kg(-1), suggesting an anthropogenic origin. This review of recent literature illustrates how levels of mercury (Hg) species in the atmosphere are effectively transported into the aquatic arena, where chemical parameters combine to determine bioaccumulation rates in fish. Limited studies on methyl mercury (MeHg) in precipitation shown that concentrations average from 5% of total-I-Ig (T-Hg), to 1% in industrial regions. Observations of increased Hg is snow and precipitation from the Arctic Circle, related to poleward atmospheric circulation patterns, also demonstrate a spring maximum accompanying ozone depletion. Increases in oxidants and soil derived Hg in the atmosphere during the summer best explain summer Hg maximums observed in precipitation, while increased temperatures raise fish metabolism increasing Hg uptake through respiration and ingestion rate. The major route of entry for MeHg to fish appears to be biomagnification, after input from precipitation, runoff and inlake methylation. Regions buffered against acid precipitation maintain low fish-Hg levels by reduced MeHg production and maintaining gill function. When considering the bioaccumulation of Hg in fish this study shows that there are many variables to consider, not all of which originate from inside the aquatic arena. Both catchment and atmospheric processes combinewith aquatic variables to dictate the overall levels of MeHg observedin fish tissue. There now appears to be sufficient knowledge to develop an axiom for the identification of aquatic systems likely to be susceptible to bioaccumulation from atmospheric derived Hg.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 04/12/20 alle ore 18:39:42