Ongoing soil arsenic exposure of children living in an historical gold mining area in regional Victoria, Australia: Identifying risk factors associated with uptake
- Authors: Martin, Rachael , Dowling, Kim , Pearce, Dora , Bennett, John , Stopic, Attila
- Date: 2013
- Type: Text , Journal article
- Relation: Journal of Asian Earth Sciences Vol. 77, no. (2013), p. 256-261
- Full Text: false
- Reviewed:
- Description: Elevated levels of arsenic have been observed in some mine wastes and soils around historical gold mining areas in regional Victoria, Australia. Arsenic uptake from soil by children living in these areas has been demonstrated using toenail arsenic concentration as a biomarker, with evidence of some systemic absorption associated with periodic exposures. We conducted a follow-up study to ascertain if toenail arsenic concentrations, and risk factors for exposure, had changed over a five year period in an historical gold mining region in western regional Victoria, Australia. Residential soil samples (N= 14) and toenail clippings (N= 24) were analyzed for total arsenic using instrumental neutron activation analysis, including 19 toenail clippings samples that were obtained from the same study cohort in 2006. Toenail arsenic concentrations in 2011 (geometric mean, 0.171. μg/g; range, 0.030-0.540. μg/g) were significantly lower than those in 2006 (geometric mean, 0.464. μg/g; range, 0.150-2.10. μg/g; p<. 0.001). However, toenail arsenic concentrations were again correlated with soil arsenic levels (Spearman's rho= 0.630; p= 0.001). Spending time outdoors more often and for longer periods correlates with increased arsenic uptake (p< 0.05). Mining-influenced residential soils represent a long-term continuing source for potential arsenic exposure for children living in this historical mining region. © 2013.
- Description: C1
Size-dependent characterisation of historical gold mine wastes to examine human pathways of exposure to arsenic and other potentially toxic elements
- Authors: Martin, Rachael , Dowling, Kim , Pearce, Dora , Florentine, Singarayer , Bennett, John , Stopic, Attila
- Date: 2016
- Type: Text , Journal article
- Relation: Environmental Geochemistry and Health Vol. 38, no. 5 (2016), p. 1097-1114
- Full Text: false
- Reviewed:
- Description: Abandoned historical gold mining wastes often exist as geographically extensive, unremediated, and poorly contained deposits that contain elevated levels of As and other potentially toxic elements (PTEs). One of the key variables governing human exposure to PTEs in mine waste is particle size. By applying a size-resolved approach to mine waste characterisation, this study reports on the proportions of mine waste relevant to human exposure and mobility, as well as their corresponding PTE concentrations, in four distinct historical mine wastes from the gold province in Central Victoria, Australia. To the best of our knowledge, such a detailed investigation and comparison of historical mining wastes has not been conducted in this mining-affected region. Mass distribution analysis revealed notable proportions of waste material in the readily ingestible size fraction (aecurrency sign250 A mu m; 36.1-75.6 %) and the dust size fraction (aecurrency sign100 A mu m; 5.9-45.6 %), suggesting a high potential for human exposure and dust mobilisation. Common to all mine waste types were statistically significant inverse trends between particle size and levels of As and Zn. Enrichment of As in the finest investigated size fraction (aecurrency sign53 A mu m) is of particular concern as these particles are highly susceptible to long-distance atmospheric transport. Human populations that reside in the prevailing wind direction from a mine waste deposit may be at risk of As exposure via inhalation and/or ingestion pathways. Enrichment of PTEs in the finer size fractions indicates that human health risk assessments based on bulk contaminant concentrations may underestimate potential exposure intensities.