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 1996-2008 (mg.m-2.yr-1)

BD TF LF RWSE16, Gammtratten 0.77 0.71 0.46 0.10SE15, Kindla 1.22 1.06 0.92

0.20SE14, Aneboda 0.76 1.08 1.230.29FI03, Hietajärvi 0.57 0.53 0.04FI01, Valkea-Kotonen 0.65 0.12LV02, Zoseni 1.01 0.910.06LV01, Rucava 1.90 1.760.11LT01, Aukstatija 0.86 0.09LT03, Zematija 1.94 0.24CZ02, Lysina 0.62 0.67 0.88CZ01, Anenske Povodi 2.83 1.34 0.07DE01, Forellenbach 1.26 1.69 1.44

1.42AT01, Zöbelboden, beech 0.93 0.86 0.73 0.31AT01, Zöbelboden, spruce0.93 1.69 0.62 0.31

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

Precipitation deposi tion

DC

Interception deposi tion

(d ry an d occult) ID

Canopy in teractions

Throughfal l, TFStemflow, SF

Li tterfal l, LF

Soi l interactions

WeatheringAccumulation

Decomposition

Mineralisation

Leaching soil water zone, SW

Ground water transport, GW

Runoff stream, RW

Approximate estim ate of total deposition, TDTD TF + LF

Fig. 1.

Approximate estimate of total deposition, TD

TD = TF + LF

Swedish University of Agricultural Sceinces

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.

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Metal content in the humus layer during 1985-2010 in the IM site SE14

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Bulk deposition (µg.m-2) at SE04 Gårdsjön

Year Cd Pb

1996 48 1727

1997 53 1810

1998 34 1294

1999 54 1887

2000 55 1653

2001 29 921

2002 35 949

2003 36 857

2204 36 988

2005 35 898

2006 41 889

2007 32 787

2008 24 508

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: 537-541Bulk 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 1995 1996, mg.m-2

Aneboda GårdsjönPb humus layer 680 690

humus layer plus 20 cm 2800 3400

Cd humus layer 3.8 2.4humus layer plus 20 cm 19

Hg humus layer 2.3 2.2humus layer plus 20 cm 9.1 9.0

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 2004.

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 Cdexceedance 12% of land area for Pbexceedance 54% of land area for Hg

based on Hg in fish, 3 countries, 97-100% of area

CCE 2010. Critical loads of Heavy Metals and their Exceedances. CCE Status Report 2010, 91-100.

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 manual1) drinking water – human health2) terrestrial food quality – human health3) terrestrial eco-toxicological effects (mainly soils)4) aquatic food quality – human health (Hg in fish)

1-3, relation to metal concentration in soil solution4, 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 2010. Environmental Pollution 158:2465-2471

crit. limit 3.3 µg.g-1

Åkerblom et al. 2010. Ecotoxicology and Environ. Safety 73: 924-931

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 Hg2+ 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 - 0.5 µg.g-1 (organic mtrl)Tipping - 3.3 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, DE01 0.4-0.8 µg.g-1 ; (Steinkreutz, 0.16 µg.g-1)

Swedish University of Agricultural Sceinces

Hg accumulation is still ongoing

Thank You for attention