Abstract

The study investigated the concentration of metals (Cd, Cr, Cu, Ni, Pb, and Zn) and S in urban dust samples of Cancun, Quintana Roo, Mexico. This is the first study about urban dust pollution in Cancun. Urban dust samples were collected and divided in three groups: high traffic densities (HT), low traffic densities (LT), and fixed sources (FS). A statistical analysis was performed using Pearson correlation, Principal Component Analysis, and k-means clustering, in order to classify the data according to each sampling site. The behaviour of the corresponding concentration distributions is shown in cartographic data using Geographic Information Systems. Results from highest to lowest concentration, are as follows: S > Zn > Pb > Cu > Cr > Ni > Cd. Concentrations were compared with NOM-147-SEMARNAT/SSA1-2004, USEPA guidelines, and atmospheric fallout in topsoil estimated by 100 years of accumulation. Almost all results meet the norm NOM-147-SEMARNAT/SSA1-2004 limit, and USEPA guideline, except Cr (two sites) and Pb (three sites). However, results at all sites are higher than the atmospheric fallout limit. The geo-accumulation index (I-geo) class presents the order: Pb > Cu > Cd > Zn > S>Cr > Ni. The research revealed that urban dust from sites with heavy traffic had the highest S, Zn and Pb concentrations, while sites considered as low traffic and fixed sources showed significantly high levels of S, Cr and Pb. The results indicate two major sources contributing to metals and sulfur in road dust: (1) traffic and emissions from vehicles, and (2) vehicular parts. Finally, the results reported in this work could be useful to the authorities in order to select priority sites to install emissions monitoring systems.

摘要

该研究调查了墨西哥金塔纳罗奥州坎昆市城市尘埃样品中金属（镉，铬，铜，镍，铅，锌和铅）和硫的浓度。这是坎昆市关于城市粉尘污染的第一项研究。收集城市灰尘样本并将其分为三类：高交通密度（HT），低交通密度（LT）和固定污染源（FS）。使用Pearson相关，主成分分析和k-均值聚类进行统计分析，以便根据每个采样点对数据进行分类。使用地理信息系统在制图数据中显示了相应浓度分布的行为。从最高浓度到最低浓度的结果如下：S> Zn> Pb> Cu> Cr> Ni> Cd。将浓度与USEPA准则NOM-147-SEMARNAT / SSA1-2004进行了比较，和通过累积100年估算出的表层土壤中的大气沉降。除铬（两个位点）和铅（三个位点）外，几乎所有结果均符合NOM-147-SEMARNAT / SSA1-2004限值和USEPA准则。但是，所有站点的结果均高于大气沉降极限。地积累指数（I-geo）类的顺序为：Pb> Cu> Cd> Zn> S> Cr> Ni。研究表明，交通繁忙的地点的城市灰尘中S，Zn和Pb的浓度最高，而交通少且固定来源的地点的S，Cr和Pb含量却很高。结果表明，造成道路灰尘中的金属和硫的两个主要来源：（1）交通和车辆排放，以及（2）车辆零件。最后，