Environmental Sciences Group, Royal Military College of Canada, Kingston, Ontario, Canada K7K 7B4.
Sci Total Environ. 2010 Jan 15;408(4):829-35. doi: 10.1016/j.scitotenv.2009.11.006. Epub 2009 Nov 27.
Arsenic is one of the most widely encountered environmental contaminants because of a number of anthropogenic sources; in Canada the main anthropogenic release of arsenic is from mine tailings ponds. The present study is part of a series of studies to measure chemical and biological effects of exposure for meadow voles (Microtus pennsylvanicus) living on arsenic contaminated sites. Two additional objectives were addressed in the present study: the effect of higher arsenic concentrations compared with previous studies, and the comparison of chemical speciation and biological effects. To obtain the higher environmental concentrations, specimens were collected from a former gold mining site in Montague, NS that contains highly elevated concentrations of arsenic in soils and plants. Meadow voles were collected and their tissues were analyzed for total arsenic to measure uptake, and arsenic speciation to examine the chemical effects of the high arsenic exposure. In addition to the arsenic analysis, a biomonitoring study was undertaken to examine the sub-cellular effects in meadow voles resulting from the elevated arsenic exposure. Meadow voles living on the contaminated site had substantially higher concentrations of total arsenic than animals from the background (reference) location. The extractable arsenic in internal tissues was present mainly as monomethylarsonic acid (up to 14% of total arsenic). A statistically significant relationship was observed between the reduction of glutathione in vole livers and the increase in liver arsenic concentrations, and micronucleated monochromatic red blood cells were also significantly elevated in voles from the arsenic contaminated site. This is one of the few field studies where sub-cellular effects were observed, and the first to show a co-existence of such effects with relatively high proportions of monomethylarsonic acid in voles living near mine tailings.
砷是一种广泛存在于环境中的污染物，因为它有多种人为来源；在加拿大，人为释放砷的主要来源是尾矿池。本研究是一系列研究的一部分，旨在测量生活在受砷污染地区的草原田鼠（Microtus pennsylvanicus）的暴露的化学和生物学效应。本研究还解决了另外两个目标：与以前的研究相比，更高浓度的砷的影响，以及化学形态和生物效应的比较。为了获得更高的环境浓度，从新斯科舍省蒙塔古的一个以前的金矿中采集了标本，该矿的土壤和植物中砷的浓度非常高。采集了草原田鼠并分析其组织中的总砷含量，以测量其吸收量，并分析砷形态，以检查高砷暴露的化学效应。除了砷分析外，还进行了生物监测研究，以检查受砷升高暴露影响的草原田鼠的亚细胞效应。与来自背景（参考）地点的动物相比，生活在污染地点的草原田鼠的总砷浓度要高得多。内部组织中的可提取砷主要以一甲基砷酸（高达总砷的 14%）的形式存在。在田鼠肝脏中谷胱甘肽的减少与肝脏砷浓度的增加之间观察到了统计学上的显著关系，并且来自受砷污染地点的田鼠中单核红细胞的微核也显著升高。这是少数观察到亚细胞效应的实地研究之一，也是第一个显示出在生活在尾矿附近的田鼠中存在这种效应与相对较高比例的一甲基砷酸共存的研究。
