Acquisition of Instruments for Environmental Science Laboratory

马里蒙特大学的杰森·W·凯尔西博士获得了一笔赠款，用于购买高效液相色谱化学站和保护器通风柜。该设备将用于研究土壤老化有机污染物的生物有效性和毒性。这项研究的重要组成部分是从土壤和暴露在受污染土壤中的有机体中检测和提取化合物。马里蒙特环境科学实验室使用高效液相色谱(HPLC)来量化从土壤中回收该化合物以及生物吸收。化学站将极大地加强对高效液相数据的分析。目前，数据是通过积分器打印到纸上的，这使得复杂的分析变得困难。通风柜将允许对多种挥发性有机污染物进行处理，否则这些污染物很难处理。环境科学实验室没有通风柜，这使得对挥发性化合物的调查变得困难和危险。该设备也将用于综合高级环境实验室的教学，在这门课程中，高年级的生物学本科生将学习多项用于实验环境科学的分析技术，并将评估石油成分菲和广泛使用的除草剂阿特拉津对蚯蚓和龟蛋的生物有效性。令人感兴趣的是物种差异对土壤老化污染物的生物有效性的影响。无菌土壤样本将用菲或阿特拉津进行修改，并允许老化预定天数。这些实验将被设计成产生其中化合物已经老化了不同长度的时间(例如，120、60、30和0天)的样品。生物将被添加到样本中，然后提取以确定化合物的组织浓度。平行样品将被提取，以确认老化后土壤中存在未改变的母体化合物(即添加的菲或阿特拉津)。萃取物将用高效液相色谱(与化学站一起)进行分析，以量化土壤对污染物的吸收和回收。这项工作对于准确评估土壤中污染物的风险非常重要。尽管调查者和其他人报告的数据表明，许多污染物在土壤中老化后，可供吸收的物质逐渐减少，但对污染场地的风险估计通常基于土壤中存在的化合物总量(即可从土壤中提取)，而不是生物可获得性。因此，与土壤中的特定污染物相关的风险往往被高估。这种不正确的风险计算可能会导致资源被误用，以试图实现不切实际和可能不必要的清理目标。此外，污染水平最高的地点可能不是对人类和生态受体风险最高的地点。以适当反映生物可获得性的方式对环境和人类健康风险进行排序的暴露评估将导致更准确的风险评估，并最终更有效地分配有限的财政和自然资源。有关物种差异的信息将改善对土壤中污染物风险的预测，并进一步加深我们对影响生物有效性的因素的理解。

A grant has been awarded to Dr. Jason W. Kelsey at Marymount University to purchase an HPLC Chemstation and a Protector fume hood. The equipment will be used to study the bioavailability and toxicity of soil-aged organic pollutants. Important components of the research are the detection and extraction of compounds from soil and organisms that have been exposed to contaminated soil. High Performance Liquid Chromatography (HPLC) is used in the Marymount environmental science laboratory to quantify both recovery of the compound from soil as well as biological uptake. The Chemstation will greatly enhance the analysis of HPLC data. Currently, data are printed onto paper by means of an integrator, making complex analysis difficult. The fume hood will allow work on a wide range of volatile organic pollutants that are otherwise difficult to handle. The absence of a fume hood in the environmental science laboratory makes investigation of volatile compounds difficult and dangerous. The equipment will also be used in the teaching of Integrated Advanced Environmental Laboratory, a course in which upper-division biology undergraduates learn a number of analytical techniques used in experimental environmental science.The bioavailability of phenanthrene, a constituent of petroleum, and atrazine, a widely used herbicide, to earthworms and turtle eggs will be assessed. Of interest is the effect of species differences on the bioavailability of soil-aged pollutants. Sterile soil samples will be amended with phenanthrene or atrazine and allowed to age for a predetermined number of days. The experiments will be designed to yield samples in which the compounds have been aged for different lengths of time (e.g., 120, 60, 30, and 0 days). Organisms will be added to the samples and then extracted to determine the tissue concentration of the compounds. Parallel samples will be extracted to confirm that the unaltered parent compounds (i.e., the added phenanthrene or atrazine) are present in the soil after aging. Extracts will be analyzed using HPLC (with the Chemstation) to quantify uptake and recovery from soil.This work is important for the accurate assessment of the risk of pollutants in soil. Although data reported by the investigator and others demonstrate that many contaminants become progressively less available for uptake as they are aged in soil, estimations of risk of polluted sites are typically based on the total amount of compound present in (i.e., extractable from) soil and not biological availability. Consequently, the risk associated with a particular contaminant in soil is frequently overestimated. This incorrect calculation of risk could lead to the misdirection of resources in an attempt to meet unrealistic and possibly unnecessary clean-up goals. In addition, sites with the highest levels of contamination may not be the sites of highest risk to human and ecological receptors. Exposure assessments that rank environmental and human health risks in a way that appropriately reflects bioavailability will lead to more accurate risk assessments and, ultimately, to more efficient allocation of limited financial and natural resources. Information about species differences will improve predictions of the risk of pollutants in soils as well as further our understanding of the factors that influence bioavailability.