Swedish University of Agricultural Sceinces Updated heavy metal budgets and critical loads Lage Bringmark & Lars Lundin
Swedish University of Agricultural Sceinces Trace metal budgets and critical loads – update and discussion Priority metals: Pb, Cd, Hg Authors: Lage Bringmark (SE), Lars Lundin (SE), Helga Dieffenbach-Fries (DE), Buchard Beudert (DE), Maria Theresia Grabner (AT), Thomas Dirnböck, (AT), Tuija Ruoho-Airola (FI), Iraida Lyulka (LV), Milan Vana (CZ), Pavel Kram (CZ) and Algirdas Augustaitis (LT).
Swedish University of Agricultural Sceinces Sites and Flows of lead (Pb) in bulk deposition (BD), throughfall (TF) and steam water runoff (RW) at IMCP IM sites for one or more years during (mg.m -2.yr -1 ) BDTFLFRW SE16, Gammtratten SE15, Kindla SE14, Aneboda FI03, Hietajärvi FI01, Valkea-Kotonen LV02, Zoseni LV01, Rucava LT01, Aukstatija LT03, Zematija CZ02, Lysina CZ01, Anenske Povodi DE01, Forellenbach AT01, Zöbelboden, beech AT01, Zöbelboden, spruce
Swedish University of Agricultural Sceinces Lead balances for the Finnish FI03 catchment and the three Swedish catchments SE14, SE15, and SE16 with throughfall, TF, litterfall, LF, and runoff, RW included. TF+LF is also included
Input Approximate estimate of total deposition, TD TD = TF + LF Swedish University of Agricultural Sceinces
Mercury balances for the four Swedish catchments SE 04, SE 14, SE 15 and SE 16 showing throughfall, TF, litterfall, LF and runoff, RW.
Swedish University of Agricultural Sceinces Metal content in the humus layer during in the IM site SE14
Swedish University of Agricultural Sceinces Bulk deposition (µg.m -2 ) at SE04 Gårdsjön YearCdPb
Swedish University of Agricultural Sceinces Stream concentrations at SE14 Aneboda, Pb µg.L -1
Swedish University of Agricultural Sceinces Hovmand et al, 2008, Env. Pollution 155: Bulk deposition 50 yr – Pb (Pacyna) 430 mg.m -2 (TF+LF approx.1300 mg.m -2 ) Bulk deposition 50 yr – Cd (Pacyna) 6.7 mg.m -2 (TF+LF approx. 27 mg.m -2 ) Bulk deposition 50 yr – Hg (Bringmark) ≈ 2.0 mg.m -2 (TF+LF approx.16 mg.m -2 ) South Swedish soil stores , mg.m -2 AnebodaGårdsjön Pbhumus layer humus layer plus 20 cm Cd humus layer humus layer plus 20 cm 19 Hghumus layer humus layer plus 20 cm9.19.0
Swedish University of Agricultural Sceinces Critical loads Cd Pb Hg On request from WGE, Europe-wide task of calculating and mapping critical loads and exceedances. Call for data in EMEP grid cells. Deposition by EMEP modelling. Exceedance of 5th percentile of critical load in each grid cell. Results on soil ecotoxicological endpoints; exceedance 0.4% of land area for Cd exceedance 12% of land area for Pb exceedance 54% of land area for Hg based on Hg in fish, 3 countries, % of area CCE Critical loads of Heavy Metals and their Exceedances. CCE Status Report 2010,
Swedish University of Agricultural Sceinces Starting point for critical load calculation – critical limit Five possible endpoints for critical load calculation – critical limit Five possible endpoints in the manual 1)drinking water – human health 2) terrestrial food quality – human health 3) terrestrial eco-toxicological effects (mainly soils) 4)aquatic food quality – human health (Hg in fish) 1-3, relation to metal concentration in soil solution 4, empiric relation to concentration in rainfall (Hg)
Swedish University of Agricultural Sceinces Critical limit for Hg, most important point and most weak South Swedish concentrations of Hg in humus layer taken as critical limit at 0.5 µg.g -1 organic. Experimental effect conc ≈ 2 µg.g -1, field observations of metal effects not independent of Pb Two recent papers on critical effect concentrations for Hg: Tipping et al Environmental Pollution 158: crit. limit 3.3 µg.g -1 Åkerblom et al Ecotoxicology and Environ. Safety 73: EC5% 0.8 µg.g -1
Swedish University of Agricultural Sceinces 52 biological endpoints (plants, invertebrates and mainly microbes) collected from literature on experimental Hg additions. Harmonization of all experiments by recalculation to free Hg 2+ ion (WHAM). Critical limit derived from 5th percentile of species sensitivity distributions. Result: 0.13 µg.g -1 (soil) or 3.3 µg.g -1 (organic mtrl) Tipping et al., 2010 Critical limit estimations
Swedish University of Agricultural Sceinces Focus on most sensitive soil layer. Upper part of humus layer – high biological activity, site of metal accumulation. Lower part less sensitive, uppermost litter layer less sensitive. Effect concentration, EC5 at 0.8 g.g -1 (organic mtrl.) Correlation: Microbial activity – metal sensitivity. Northern sites more sensitive than southern ones. Åkerblom et al., 2010 Critical limit estimations in Sweden
Swedish University of Agricultural Sceinces Soil effect concentrations for mercury Current µg.g -1 (organic mtrl) Tipping µg.g -1 (organic mtrl) Åkerblom- 0.8 µg.g -1 (organic mtrl) Existing Hg concentrations in forest humus layers: North Sweden, general 0.2 µg.g -1, chloralcali industry 0.9 µg.g -1 South Sweden, general 0.35 µg.g -1 Czech Republic, general 0.7 µg.g -1, DE µg.g -1 ; (Steinkreutz, 0.16 µg.g -1 )
Swedish University of Agricultural Sceinces Hg accumulation is still ongoing Thank You for attention