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Kvetoslav R. Spurny Werner Stober Evelyn R. Ackerman J.P. Lodge Jr. Kvetoslav Spurny Jr. 《Journal of the Air & Waste Management Association (1995)》2013,63(5):496-498
Despite the fact that adverse health effects of asbestos have been known since shortly after the turn of the century,1 there has been little progress in techniques for determining the mineral in the airborne state. This absence of sampling and analysis methods appears to derive from two main sources: (1) In the environments of the asbestos using industries, asbestos concentrations tend to be high relative to other particulate species, and especially compared with other fibrous species, making estimation of concentration by microscopy relatively easy. (2) The term "asbestos" describes a crystal habit, not a chemical compound; therefore there is no unique chemical property of asbestos that can be used as the basis for its measurement. Interestingly, there appears to be no basis for distinguishing the health effects of one type of asbestos over another;2 the physiological response seems more dependent on crystal habit than on composition. 相似文献
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Peterson GS Axler RP Lodge KB Schuldt JA Crane JL 《Environmental monitoring and assessment》2002,78(2):111-129
A fluorometric screening method was used to estimate total polycyclic aromatic hydrocarbon (t-PAH) concentrations in sediments collected from the St. Louis River Area of Concern (AOC) in northeastern Minnesota. Sediments were collected as part of a Regional Environmental Monitoring and Assessment Program (R-EMAP) study to assess sediment quality in the AOC. The screening method was calibrated using a PAH surrogate standard consisting of eight PAHs commonly found in the St. LouisRiver system, at their approximate proportions. Estimated PAHconcentrations were compared to GC/MS measured `true' PAH concentrations to evaluate the overall predictive power of thescreening method. Regression analysis of log transformed estimated versus true PAH concentration yielded an r2 of 0.72 (n = 86). In addition, the rates of false positive and false negative predictions associated with the screening methodwere determined relative to different sediment effects concentrations (SECs) for total PAHs. In general, the rate of false positive predictions was shown to increase as the SEC criteria value decreased, while false negative rates remainedconsistently low (below 7%). Methodological recommendations which led to a three-fold reduction in false negatives, and theimproved prediction of both high and low PAH samples, are presented. 相似文献
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