FLUCTUATING ASYMMETRY IN ISOPODS AS INDICATOR OF HAZARDOUS METALS IN URBAN AREA

有害金属是全世界高度工业化城市地区的一个重大人类健康问题。不幸的是，人类的疾病往往只有在长时间接触后才会出现，而延迟发现在经济上和生活质量方面都是昂贵的。此外。直接监测人体中的金属（例如，通过血液样本）在后勤上是复杂和侵入性的，因此难以确定有风险的人群。作为污染监测的有吸引力的替代方案，“哨兵”动物物种最近受到了相当大的关注。作为监测仪，“哨兵”必须在生物健康和环境质量之间表现出可预测的关系。健康决定因素应具有可重复性并易于测量。对双侧对称的细微偏差（如波动不对称）提供了这样一种测量方法。在实验室和对各种压力源的实地研究中，生物体对对称的平均偏差随着压力水平的增加而增加（即，完美的双边对称的发展被破坏）。陆地等足类动物的波动不对称性为城市环境中有害金属的监测提供了一种新的、可能广泛应用的系统。这些食腐甲壳类动物在世界各地的城市和农村地区都很丰富，很容易通过主动或被动取样收集，并积累高水平的金属（包括铜、锌、镉和铅），这些金属将在它们的整个生命中保留下来。一项对等足类动物Armadillidium vulgare左右眼复眼“晶状体”（小眼）数量的初步研究显示，与工业化程度较低地区的等足类动物相比，在芝加哥南部金属污染地区收集的等足类动物中，小眼数量的不对称性明显更大。动物体内的平均不对称性与铍、铬、锰、铁、铜、锌、镉、钡、汞和铅的总浓度呈近似线性的剂量反应关系（r2=0.89）。这一建议是评估波动不对称等足类作为衡量危险金属污染的六个城市社区在芝加哥南部，伊利诺伊州卡吕梅特湖地区。该地区的居民区周围有大量的金属污染源，大部分是在金属污染的填充物上建造的，包括：钢铁工业和工业废料、煤/焦炭灰和污泥。如果成功，我们的方法作为一种方便、廉价和广泛适用的早期预警系统，对于识别有毒金属对人类健康的长期威胁具有极大的价值。

Hazardous metals are a significant human health problem in heavily industrialized urban areas worldwide. Unfortunately, human pathologies often appear only after prolonged exposure, and delayed detection is costly both financially and in terms of quality of life. Furthermore. direct monitoring of metals in humans (e.g., through blood samples) is logistically complex and intrusive, making it difficult to identify populations at risk. 'Sentinel' animal species have received considerable recent attention as attractive alternatives for pollution monitoring. For use as a monitor, 'sentinels' must exhibit a predictable relationship between organism health and environmental quality. The health determinant should be reproducible and easily measured. Subtle deviations from bilateral symmetry (e.g., fluctuating asymmetries) offer such a measure. In both laboratory and field studies of a wide range of stressors, the average deviation from symmetry in organisms increases with increased stress levels (i.e., the development of perfect bilateral symmetry is disrupted). Fluctuating asymmetry in terrestrial isopods offers a new and potentially widely-applicable system for monitoring hazardous metals in urban environments. These detritivorous crustaceans are abundant in urban and rural areas worldwide, are easily collected by active or passive sampling, and accumulate high levels of metals (including copper, zinc, cadmium, and lead), which they retain for their entire lives. A pilot study of the numbers of compound eye 'lenses' (ommatidia) in the right and left eyes of the isopod Armadillidium vulgare revealed that asymmetry in ommatidia number was significantly greater in isopods collected from metal-contaminated sites in south Chicago, compared to isopods in less industrialized areas. Average asymmetry increased in a nearly linear dose- response relationship with total concentrations of beryllium, chromium, manganese, iron, copper, zinc, cadmium, barium, mercury, and lead in the animals (r2=0.89). This proposal is to evaluate fluctuation asymmetry in isopods as a measure of hazardous metal contamination in six urban neighborhoods in the Lake Calumet district of south Chicago, Illinois. Residential areas in this region are surrounded by numerous sources of metal pollution, and the majority are constructed atop metal-contaminated fill material, including: steel industry and industrial waste, coal/coke ash, and sludge. If successful, our approach could prove extremely valuable as a convenient, inexpensive and widely-applicable early warning system for identifying long-term threats to human health from toxic metals.