1. Japan’s recent activities on mercury
Exposures and health research on mercury
MoE, Minamata research center
New development on the comprehensive strategy of toxic metal control (including mercury)
Up-to-date material flow analysis
Mercury and Pb, Cd
Input/output to/from and within Japan
Emission estimation
Industrial sectors
Municipal/industrial incinerators
Products
Measurement of consumer products
Review of new/existing mercury reduction technologies
Environmental monitoring
Fate modeling

2. Status of multimedia modeling efforts of mercury fate and transport
Noriyuki Suzuki, Yoshitaka Imaizumi, Takeo Sakurai, Kiyoshi Tanabe, Hiroaki Shiraishi and Yasuyuki Shibata
National Institute for Environmental Studies, Japan

3. General understanding of the fate of mercury : taken from UNEP Global Assessment report

4. Multimedia fate model/concept of trace chemicals
Cowan, et al. (1995)

5. General structure of G-CIEMS multimedia model
LAND
AIR
RIVER
SEA
MULTIMEDIA
Multimedia fate process on geo-referenced environment
Advective and inter-media transport processes
Transformation from parent to daughter products

6. Global G-CIEMS: preliminary case study
Model domain
Global, 2.5 x 2.5 degrees (in general)
Single Arctic and Antarctic region
Target compound and emission estimation
PCB #153 and Hg
Emission estimation is based on Breivik, et al.
Environmental media
Air grids: 2.5 x 2.5 degree
Soil compartment with essential same resolution of air
Single generic sea compartment
Meteorological data
Yearly average meteorological data
Needs to be incorporate more detailed temporal resolution
Model used
G-CIEMS multimedia fate model
Global expansion of spatially-resolved regional multimedia fate model

7. Emission pattern and air concentration of PCB#153 simulated by G-CIEMS model
10-6
10-11
10-15
(kg/s)
Air concentration
101
10-8
10-18
(pg/m3)

8. Model intercomparison study
Fig. 8. Particulate dry deposition flux from the atmosphere to different types of underlying surface, ng/m2/h
POP model intercomparison study (MSC-E/EMEP)

9. Simplified mercury speciation for multimedia model simulation by our model
Hg(0)
Hg(p)
Hg2+
MeHg
Air
Water
Soil
Sediment
・Hg(0), Hg2+, Hg(p)
・Dry/wet depositions and other inter-media processes for each species
・In soil, water and sediment, Hg(0), Hg2+, MeHg
・Methylation to MeHg tentatively assumed
- Inter-media processes among air, water, soil and sediment

10. Mercury emission data for preliminary calculation (Pachyna, Y. , et al
10-3
10-7
10-11

11. Concentration of total Hg in air
10-10
10-15
10-20
Simulated air concentration at cape Hedo in Okinawa, Japan
Hg0 (ng/m3)
Hg2+ (pg/m3)
Hg(p) (pg/m3)
Total (ng/m3)
Conc.
1.1
0.83

12. Working issues
Need for the improvement of the air compartments to be compared to the atmospheric transport models
Development of the mercury-specific fate processes in other media when necessary
Extensive validation to the measured data in air and possible other media