Environmental Research Laboratory, School of Civil Engineering, Iran University of Science and Technology, Narmak, Tehran, 16846, Iran.
School of Environment, College of Engineering, University of Tehran, Tehran, Iran.
Ecotoxicol Environ Saf. 2020 Jan 15;187:109838. doi: 10.1016/j.ecoenv.2019.109838. Epub 2019 Oct 31.
Due to population growth and the considerable increase in usage of the resources, Human environment quality has been highly threatened by pollutants in recent decades. Polycyclic aromatic hydrocarbons (PAHs) are widespread, persistent organic pollutants which are of great concern due to their carcinogenicity. The present study is the first investigation that assesses contamination, sources and cancer risk of 16 priority PAHs proposed by US EPA in urban dust samples (n = 80) taken in different land-uses of Tehran metropolis, the capital of Iran. Gas chromatography-mass spectrometry (GC-MS) is used to measure PAHs concentrations. The results showed that the average concentration of the total 16 PAHs and the average Benzo[a]pyrene total potency equivalency were 566 μg kg dry weight and 36.4 μg kg, respectively. In the commercial and residential land-uses high molecular weight (HMW) PAHs were dominated, whereas in green lands, light molecular weight (LMW) PAHs showed maximum contribution. The highest concentration of total PAHs were observed in the commercial areas due to limited air circulation and heavy traffic loads. Incremental Lifetime Cancer Risk (ILCR) model was applied to evaluate the cancer risk of exposure to PAHs contaminated dust. Based on the results, Tehran's residents (children and adults) in various land-uses except for green lands, are in high potential cancer risk of PAHs via ingestion and dermal contact exposure routs. Ace, Chr, Pyr, and BghiP which are indicators of traffic emissions, were found to be predominant PAH contributors in urban dust of commercial areas. Also, Ace, Fl, Phe, and BghiP which are derived from fossil fuel combustion, were mainly observed in the industrial land-use. Based on the results of factor analysis and diagnostic ratios, Diesel/gasoline engine vehicular emissions and combustion were found to be the main sources of PAHs in urban dust of Tehran.
由于人口增长和资源使用量的大幅增加，近几十年来，污染物对人类环境质量造成了严重威胁。多环芳烃（PAHs）是广泛存在的持久性有机污染物，由于其致癌性而备受关注。本研究首次评估了伊朗首都德黑兰不同土地利用类型的城市灰尘样本（n=80）中，美国环保署（EPA）提出的 16 种优先 PAHs 的污染程度、来源和致癌风险。采用气相色谱-质谱联用仪（GC-MS）测量 PAHs 浓度。结果表明，16 种 PAHs 总量和苯并[a]芘总效价当量的平均值分别为 566μg/kg 干重和 36.4μg/kg。在商业和住宅用地中，高分子量（HMW）PAHs 占主导地位，而在绿地中，低分子量（LMW）PAHs 贡献最大。由于空气流通受限和交通负荷较重，商业区域的总 PAHs 浓度最高。采用增量终生癌症风险（ILCR）模型评估了 PAHs 污染灰尘暴露的致癌风险。根据结果，除绿地外，德黑兰不同土地利用类型的居民（儿童和成人），通过摄入和皮肤接触途径接触 PAHs，具有较高的潜在致癌风险。Ace、Chr、Pyr 和 BghiP 是交通排放的指标，被发现是商业区域城市灰尘中主要的 PAH 贡献者。此外，Ace、Fl、Phe 和 BghiP 源自化石燃料燃烧，主要存在于工业区。基于因子分析和诊断比的结果，柴油/汽油发动机车辆排放和燃烧被认为是德黑兰城市灰尘中 PAHs 的主要来源。
