Karthikeyan Sathrugnan, Perumal Sundararajan Venkatesa, Balasubramanian Rajasekhar, Zuraimi Mohammed Sultan, Tham Kwok Wai
Division of Environmental Science and Engineering, National University of Singapore, Singapore.
J Air Waste Manag Assoc. 2007 Aug;57(8):974-80. doi: 10.3155/1047-3289.57.8.974.
An improved ion chromatographic (IC) method has been developed for the separation of nitrate in filter extracts in the presence of high concentrations of nitrite. This analytical method was successfully used for an indirect measurement of ozone (O3) in outdoor and indoor air, following its collection using a nitrite-impregnated passive sampler. The limit of detection and the limit of quantification, using the modified IC method, were 6 microg l(-1) (3sigma) and 20 microg l(-1) (10sigma), respectively. Improved detection limits and low baseline noise were obtained with the use of eluent generator and high-capacity ion exchange column. The optimized method was used for assessing O3 concentration in both indoor and outdoor environments of 28 child care centers (CCCs) located in different parts of Singapore. The O3 concentrations ranged from 0.1 to 11.95 parts per billion (ppb) in indoor and from 3.2 to 21.7 ppb in outdoor environments during the study period. It was found that, among the CCCs investigated in this study, air-conditioned CCCs and those located in close proximity to traffic emissions had significantly lower O3 concentrations indoors.
已开发出一种改进的离子色谱（IC）方法，用于在高浓度亚硝酸盐存在下分离过滤器提取物中的硝酸盐。该分析方法成功用于通过亚硝酸盐浸渍的被动采样器收集室外和室内空气中的臭氧（O3）后进行间接测量。使用改进的IC方法，检测限和定量限分别为6微克/升（3σ）和20微克/升（10σ）。通过使用洗脱液发生器和高容量离子交换柱，获得了改进的检测限和低基线噪声。优化后的方法用于评估新加坡不同地区28个儿童保育中心（CCC）室内和室外环境中的O3浓度。在研究期间，室内O3浓度范围为0.1至11.95十亿分比（ppb），室外为3.2至21.7 ppb。研究发现，在本研究调查的CCC中，有空调的CCC以及那些靠近交通排放源的CCC室内O3浓度明显较低。
