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Use of Mercury Isotopes to Quantify Mercury Exposure Sources in Inland Populations, China
journal contribution
posted on 2018-04-13, 00:00 authored by Buyun Du, Xinbin Feng, Ping Li, Runsheng Yin, Ben Yu, Jeroen E. Sonke, Benjamin Guinot, Christopher W.
N. Anderson, Laurence MauriceMercury
(Hg) isotopic compositions in hair and dietary sources
from Wanshan (WS) Hg mining area, Guiyang (GY) urban area, and Changshun
(CS) rural area were determined to identify the major Hg exposure
sources of local residents. Rice and vegetables displayed low δ202Hg and small negative to zero Δ199Hg, and
are isotopically distinguishable from fish which showed relatively
higher δ202Hg and positive Δ199Hg.
Distinct isotopic signatures were also observed for human hair from
the three areas. Shifts of 2 to 3‰ in δ202Hg between hair and dietary sources confirmed mass dependent fractionation
of Hg isotopes occurs during metabolic processes. Near zero Δ199Hg of hair from WS and CS suggested rice is the major exposure
source. Positive Δ199Hg of hair from GY was likely
caused by consumption of fish. A binary mixing model based on Δ199Hg showed that rice and fish consumption accounted for 59%
and 41% of dietary Hg source for GY residents, respectively, whereas
rice is the major source for WS and CS residents. The model output
was validated by calculation of probable daily intake of Hg. Our study
suggests that Hg isotopes can be a useful tracer for quantifying exposure
sources and understanding metabolic processes of Hg in humans.