This work provides a comprehensive report on the chemical composition of 47 major and trace elements in Tillandsia recurvata (L.) L. and top soil samples from the cities of Cienfuegos and Santa Clara in Cuba. The main aims were to provide new information on the urban pollution degree in Caribbean urban regions where the availability of data of urban health indicators are very limited and to identify the main pollution sources. The abundance of the analyzed elements at both type of samples were different at each urban regions suggesting the influence of various sources. Top soils were slightly contaminated with Zn, V, Ba, Pb, Ni, Cr, Cu, Co and Hg and seriously contaminated with Ni and Cr in Santa Clara. These and other elements such as Se, S, P, Cd, Mo and Ca where highly enriched in T. recurvata indicating a significant impact of anthropogenic sources in the air quality of both urban areas. Cluster analysis helped us associate most of the elements with an anthropogenic origin with three main pollution sources: road traffic, industrial emissions and oil combustion. The spatial variability was particularly useful to identify some of these sources including the emissions from diesel and fuel oil combustion in power stations, biomass burning and metallurgic industries. The results also showed that V and Ni were strongly associated to the oil combustion and that V/Ni ratio indices in both indicators can be used to trace this type of sources. The results presented in this study co

Carbon and nitrogen stable isotope compositions (delta 13C and delta 15N) of organic matter (OM) and total organic carbon to total nitrogen ratio (Corg/TN) in a sediment core collected in Sagua estuary (Cuba), were investigated to elucidate the origin of the Sedimentary OM (SOM) and changes in its main sources, over the last 100 years. Results showed almost constant values in the elemental and isotope composition of SOM from 1908 to 1970 with an abrupt change after 1970. From 1970 to 2005, delta 13C increased from -21.2 up to -19.3 parts per thousand, while delta 15N declined from 1.5 to values close to 0 parts per thousand. The output of the mass-balance model for the identification of OM sources indicated that delta 13C and Corg/TN values are generally influenced by marine Particulate OM (POM) sources. Between 1900 and 1970, the main OM source in sediments was marine POM (>85 %), with freshwater POM contributing ca. 15%. Since 1970, the establishment of the Alacranes Dam determined drastic environmental changes influencing the OM sources in the area. Mixing models pointed to seagrasses (79 %) as the main contributors to SOM in the first period, while since 1973 onward, the contribution of human-derived sources such as fertilizers and urban discharges became greater. This information can provide baseline data for the environmental management of the Sagua watershed.

This study investigates the contents, distribution patterns, and sources of lanthanoid elements (La to Lu) in aerosols with an aerodynamic diameter <= 10 mu m (PM10) in a coastal Caribbean region in order to better constrain the origin of the atmospheric PM contamination. We sampled and analysed PM10 aerosols during 2015 simultaneously at a rural and an urban site in Cienfuegos (Cuba) as well as particles samples from regional contamination sources. Results showed that the sum of the studied lanthanoids concentrations ranged from 0.03 to 13.42 ng m(-3) and from 0.51 to 18.75 ng m(-3) at the rural and the urban site, respectively. Time variations for the lanthanoid concentrations displayed similar trends and showed that the highest concentrations corresponded to the influence of the African dust for both sites, but presented distinct variability and lower concentrations when dust intrusions were less frequent. The lanthanoid distribution patterns in the rural and urban sites were significantly different, due to the impact of different local combustion sources. Our results were comforted by comparing the degree of fractionation of the lighter and heavier lanthanoids and the delta Eu and delta Ce anomalies between our PM10 samples and those of the local sources of contamination. Ultimately, we highlight the added value of lanthanoid elements as reliable indicators for discriminating emission sources and for tracking the origin of atmospheric particulate matter.

In this study, PM10 aerosol samples were collected at 4 urban and 1 rural sites in the region of Cienfuegos (Cuba) and analyzed for their chemical compositions (total carbon (TC), total nitrogen (TN), NH4+, Cl-, NO3- and SO42-) and their stable carbon (delta C-13) and nitrogen (delta N-15), and radioactive (Pb-210, Be-7, Cs-137 and K-40) isotope systematics, in order to better constrain both their sources of pollution and their atmospheric dynamics. The average PMic, concentrations varied from 21.67 +/- 8.54 mu g.m(-3) at the rural site to 39.01 +/- 8.23 mu g m(-3) at an urban site characterized by high road traffic. Chemical compositions showed low variability and similar abundances of the ionic species, but we observed strong correlations between i) NH4+ and SO42- that indicates the formation of secondary ammonium bisulfate (NH4HSO4), and ii) between PM10, and TC highlighting the significant influence of carbonaceous aerosols. We are reporting here the first Pb-210 aerosol concentrations in this region and demonstrate that, coupled with the corresponding Be-7 concentrations, they allow characterizing the dynamics of the regional continental air masses. delta C-13 values in PM10, appear to be controlled by i) emissions from different types of combustion sources, including fossil fuel and biomass burning and ii) carbonate inputs from the industrial activities located around the limestone quarries, east of the city.

Road dust is an indicator widely used when monitoring contamination and evaluating environmental and health risks in urban ecosystems. We conducted an exhaustive characterization of road dust samples coupling their chemical characteristics and stable isotope compositions (C and N) with the aim of evaluating the levels and spatial distribution of local contamination as well as to identify its main source(s) in the coastal city of Cienfuegos (Cuba). Results indicate that the concentrations of several elements(total nitrogen, S, Ca, V, Cu, Zn, Mo, Sn, Hg, and Pb) exceed the background values reported for both Cuban soils and the upper continental crust (UCC) and showed high variability among the sampling sites. We show that road dust contamination in Cienfuegos induces high associated ecological risks. Among the studied elements, Cd and Hg are the major contributors to environmental contamination in the city, mainly along busy roads and downtown.¿13Cand¿15N, coupled to a multivariate statistical analysis, help associate the studied elements to several local sources of contamination: mineral matter derived from local soils, cement plant and related activities, road pavement alteration, power plant, road traffic, and resuspension of particulate organic matter (POM). Our results suggest that incorporating the chemical and isotope monitoring of road dust may help implement more effective environmental management measures in order to reduce their adverse impact on ecosystems.

Atmospheric deposition is considered to be the major pathway by which substances from the atmosphere enter to the terrestrial and aquatic ecosystems. This study constitutes the first exhaustive report on trace metal deposition in Cuba and is aimed to determine the monthly atmospheric flux of 47 major and trace elements in a Caribbean coastal site and investigate the main sources contributing to deposition.

The constant increase of anthropogenic emissions of aerosols, usually resulting from a complex mixture from various sources, leads to a deterioration of the ambient air quality. The stable isotope compositions (delta C-13 and delta N-15) of total carbon (TC) and nitrogen (TN) in both PM10 and emissions from potential sources were investigated for first time in a rural and an urban Caribbean costal sites in Cuba to better constrain the origin of the contamination. Emissions from road traffic, power plant and shipping emissions were discriminated by coupling their C and N contents and corresponding isotope signatures. Other sources (soil, road dust and cement plant), in contrast, presented large overlapping ranges for both C and N isotope compositions. delta C-13(PM10) isotope compositions in the rural (average of -25.4 +/- 1.2 parts per thousand) and urban (average of -24.8 +/- 1.2 parts per thousand) sites were interpreted as a mixture of contributions from two main contributors: i) fossil fuel combustion and ii) cement plant and quarries. Results also showed that this last source is impacting more air quality at the urban site. A strong influence from local wood burning was also identified at the rural site. These conclusions were comforted by a statistical analysis using a conditional bivariate probability function. TN and delta N-15 values from the urban site demonstrated that nitrogen in PM10 was generated by secondary processes through the formation of (NH4)(2)SO4.

The deterioration of the air quality is a global concern. Daily PM10 samples were simultaneously collected and chemically characterized at an urban and a rural site in Cienfuegos, Cuba between January 2015 and January 2016. A source apportionment study was conducted in order to identify and quantify the main contributions of both local and long-range sources. Concentrations of PM10 varied similarly at the urban and rural site, with annual averages of 35.4 and 24.8 ug m-3, respectively. The highest concentrations were observed between March and August at both sites, when a strong influence of Saharan dust was identified. The PM10 daily limit (50 ug m-3) established in the Cuban legislation for air quality was exceeded by 3 and 8 times in the rural and urban site, respectively. The chemical characterization of PM10 showed important contributions of mineral matter, total carbon and secondary inorganic compounds in the region, with the highest concentrations observed at the urban site. Marine contribution, by contrast, was higher at the rural site. The highest EFs were obtained for the typical road traffic tracers Mo and Cu. Positive matrix factorization (PMF) analysis coupled with conditional bivariate probability function (CBPF) and concentration weighted trajectory (CWT) identified 5 main sources in the studied sites: Saharan intrusions, marine aerosol, combustion sources and secondary aerosols, road traffic and cement plant.

This study assesses the level of background radiation for Cienfuegos Province, Cuba. Measurements of outdoor gamma radiation (of terrestrial and cosmic origin) in air were performed at 198 locations using a GPS navigator and a dose meter (SRP-68-01, 30 x 25 mm NaI detector). The average absorbed dose was found to be 73.9 nGy h(-1) (17.2-293.9 nGy h-1), corresponding to an annual effective dose of 74.7 mu Sv (21-324 mu Sv). When compared with the data available for other places, the absorbed gamma doses obtained in this study indicate a background radiation level that falls within natural limits for the Damuji, Salado and Caonao watersheds; however, the Arimao and Gavilanes watersheds present levels of the absorbed dose and annual effective dose comparable with high background radiation areas. An isodose map of the terrestrial gamma dose rate in Cienfuegos was drawn using the GIS application "Arc View". This study provides important baseline data of radiation exposure in the area.