title: Two Centuries of Coral Skeletons from the Northern South China Sea Record Mercury Emissions from Modern Chinese Wars.
abstract: The contemporary mercury (Hg) cycle in the world's oceans has been greatly affected by human activities. However, we are still lacking reliable, long-term, and continuous records of Hg in seawater. Here, we report for the first time on using annually banded Porites coral skeletons from the northern South China Sea (SCS) as an archive for recording changes of seawater dissolved Hg spanning the past two centuries. We developed a combustion-trapping method to preconcentrate ultratrace Hg concentrations from coral aragonitic skeletons for highly accurate total Hg measurements. Results show that Hg in the coral skeletons ranges from 0.3 to 5.1 pmol/g and is discriminated against Ca during coral skeletal calcification. Preindustrial (1798-1832) Hg levels in coral skeletons were found to be approximately 0.5 pmol/g. The highest Hg concentrations (3-5 pmol/g) were observed during the WWII period (1933-1942). Other distinct Hg maxima (∼3 pmol/g) are observed for the periods 1833-1847, 1858-1862, 1918-1927, 1978-1982, and 1988-1992, with the first four coinciding with contemporary Chinese wars. Our study suggests that the production and use of ammunitions in those wars likely account for the primary Hg emission sources in the northern SCS before 1950, and coral is potentially a robust indicator of historical, regional Hg contamination events.
authors.affiliation: CAS Key Laboratory of Crust-Mantle Materials and Environment, School of Earth and Space Sciences, University of Science and Technology of China , Hefei, Anhui 230026, China.|Water Quality Centre, Trent University , 1600 West Bank Drive, Peterborough, Ontario K9L 0G2, Canada.
authors.forename: Ruoyu
authors.initials: R
authors.lastname: Sun
authors.affiliation: Water Quality Centre, Trent University , 1600 West Bank Drive, Peterborough, Ontario K9L 0G2, Canada.
authors.forename: Holger
authors.initials: H
authors.lastname: Hintelmann
authors.affiliation: CAS Key Laboratory of Crust-Mantle Materials and Environment, School of Earth and Space Sciences, University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: CAS Key Laboratory of Crust-Mantle Materials and Environment, School of Earth and Space Sciences, University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Li
authors.affiliation: Water Quality Centre, Trent University , 1600 West Bank Drive, Peterborough, Ontario K9L 0G2, Canada.
authors.forename: Brian
authors.initials: B
authors.lastname: Dimock
mesh_terms: D000818:Animals; D037421:Anthozoa; D002681:China; D004784:Environmental Monitoring; D008628:Mercury; D012623:Seawater; D014857:Warfare
chemical_list: D008628:Mercury