A 700-year record of mercury in avian eggshells of Guangjin Island, South China Sea

• Published in: Environmental pollution (1987) 2011-04, Vol.159 (4), p.889-896
• Main Authors: Xu, Li-Qiang, Liu, Xiao-Dong, Sun, Li-guang, Chen, Qian-Qian, Yan, Hong, Liu, Yi, Luo, Yu-Han, Huang, Jing
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Animals; Anthropogenic pollution; Applied ecology; Aves; Biological and medical sciences; Birds - metabolism; China; Deposition; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Egg Shell - chemistry; Egg Shell - metabolism; Eggshell; Environmental Monitoring; Environmental Pollution - history; Fundamental and applied biological sciences. Psychology; Geologic Sediments; Guangjin Island; History, 17th Century; History, 18th Century; History, Medieval; Human; Islands; Marine environments; Markers; Mercury; Mercury - analysis; Mercury - metabolism; Microscopy, Electron, Scanning; Nitrogen Isotopes - analysis; Nitrogen Isotopes - metabolism; Pollution abatement; South China Sea; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - metabolism
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2010.12.021

Ancient eggshells over the past 700 years were extracted from an ornithogenic sediment profile on Guangjin Island, South China Sea. Based on SEM and nitrogen isotope analyses, we determined that neither post-depositional processes nor seabirds’ dietary changes had a large influence on eggshell Hg levels. The historical change of Hg in these eggshells was reconstructed. Eggshell Hg was a marker for past Hg deposition in marine environment. The eggshell Hg showed three small peaks at around 1300AD, 1600 AD and 1700–1750AD and rapid increase since 1800 AD. Before 1970 AD the Hg deposition in the Xisha area had global distribution characteristics, with increased Hg emissions due to global anthropogenic activities in industrial times. However, after 1970 AD, a further sharp increase up to present day occurred, implying that the Hg production center had gradually shifted from Europe and America to Asia. ► Eggshell Hg is a marker for past mercury deposition in marine environment. ► This is a Hg record from ancient sequential eggshell samples. ► The 700-year record of eggshell Hg is closely related to human activities. ► Eggshell Hg suggests the increase of Hg production in Asia over the past decades. Our work provides a potential use of ancient sequential eggshells to reconstruct past mercury deposition in marine ecosystems.