PM2.5 and PM10 samples were collected at 4 and 14 sampling sites, respectively, located in the Metropolitan area of Costa Rica (MACR), during 2010-2011. These sites were representative of commercial, industrial and residential zones of this region. Concentrations of elemental carbon (EC) and organic carbon (OC) were analyzed using the IMPROVE thermal-optical reflectance (TOR) method. OC and EC concentrations were higher in commercial and industrial sites and showed clear seasonal variations with higher concentrations observed in the rainy season (May-November) than in the dry season (December-April), due to wind patterns in the study area. Total carbonaceous aerosol accounted for 35% of PM10 and 56% of PM2.5 mass. Good correlation between OC and EC in PM10 (R=0.89-0.75) and PM2.5 (R=0.79-0.64) indicated that they had common dominant sources of combustion such as industrial activities and traffic emissions. The annual average concentrations of estimated SOC (Secondary Organic Carbon) in the MACR PM10 samples showed values between 0.65-8.49 mg/m3, accounting for 48% and 56% of the OC in PM10 and PM2.5 respectively. Positive Matrix Factorization (PMF) identified five principal sources for OC and EC in particles: gasoline vehicles, diesel vehicles, on road traffic, wood smoke and industrial combustion. The contribution of each of the source varied between the PM10 and PM2.5 size fractions. | Se recolectaron muestras de PM2.5 y PM10 en 4 y 14 sitios de muestreo, respectivamente, ubicados en el Área Metropolitana de Costa Rica (MACR), durante 2010-2011. Estos sitios eran representativos de zonas comerciales, industriales y residenciales de esta región. Las concentraciones de carbono elemental (CE) y carbono orgánico (OC) se analizaron utilizando el método IMPROVE termoóptica reflectancia (TOR). Las concentraciones de OC y CE fueron mayores en los sitios comerciales e industriales y mostraron claras variaciones estacionales con concentraciones más altas observadas en la temporada de lluvias (mayo-noviembre) que en la estación seca (diciembre-abril), debido a los patrones de viento en el área de estudio. El aerosol carbonoso total representó el 35% de PM10 y el 56% de la masa de PM2.5. La buena correlación entre OC y EC en PM10 (R = 0,89-0,75) y PM2,5 (R = 0,79-0,64) indicó que tenían fuentes de combustión dominantes comunes como las actividades industriales y las emisiones de tráfico. Las concentraciones medias anuales de SOC (Carbono Orgánico Secundario) estimado en las muestras MACR PM10 mostraron valores entre 0.65-8.49 mg / m3, representando el 48% y 56% de la OC en PM10 y PM2.5 respectivamente. La Factorización de Matriz Positiva (PMF) identificó cinco fuentes principales de OC y EC en partículas: vehículos de gasolina, vehículos diesel, en el tráfico rodado, humo de leña y combustión industrial. La contribución de cada una de las fuentes varió entre las fracciones de tamaño PM10 y PM2.5. | As amostras de PM2.5 e PM10 foram coletadas em 4 e 14 locais de amostragem, respectivamente, localizados na área metropolitana da Costa Rica (MACR), durante 2010-2011. Esses locais eram representativos das zonas comerciais, industriais e residenciais desta região. As concentrações de carbono elementar (CE) e carbono orgânico (OC) foram analisadas usando o método IMPROVE de refletância ótica-térmica (TOR). As concentrações de OC e EC foram maiores nos locais comerciais e industriais e mostraram claras variações sazonais com maiores concentrações observadas na estação chuvosa (maio-novembro) do que na estação seca (dezembro-abril), devido aos padrões de vento na área de estudo. O aerossol carbonáceo total foi responsável por 35% da massa de PM10 e 56% da massa de PM2,5. A boa correlação entre OC e EC em PM10 (R = 0,89-0,75) e PM2,5 (R = 0,79-0,64) indicou que eles tinham fontes dominantes comuns de combustão, como atividades industriais e emissões de tráfego. As concentrações médias anuais estimadas de SOC (Carbono Orgânico Secundário) nas amostras MACR PM10 apresentaram valores entre 0,65-8,49 mg / m3, representando 48% e 56% do OC em PM10 e PM2,5 respectivamente. A Fatoração de Matriz Positiva (PMF) identificou cinco fontes principais de CO e CE em partículas: veículos a gasolina, veículos a diesel, no tráfego rodoviário, fumaça de lenha e combustão industrial. A contribuição de cada uma das fontes variou entre as frações de tamanho PM10 e PM2,5. | Universidad Nacional, Costa Rica | Universidad de Costa Rica | Instituto Nacional de Ecología, Mexico | Universidad Nacional Autónoma de México, México | Escuela de Ciencias Ambientales

This manuscript evaluates spatial and temporal variations of source contributions to ambient fine particulate matter (PM2.5) in Israeli, Jordanian, and Palestinian cities. Twenty-four hour integrated PM2.5 samples were collected every six days over a 1-year period (January to December 2007) in four cities in Israel (West Jerusalem, Eilat, Tel Aviv, and Haifa), four cities in Jordan (Amman, Aqaba, Rahma, and Zarka), and three cities in Palestine (Nablus, East Jerusalem, and Hebron). The PM2.5 samples were analyzed for major chemical components, including organic carbon and elemental carbon, ions, and metals, and the results were used in a positive matrix factorization (PMF) model to estimate source contributions to PM2.5 mass. Nine sources, including secondary sulfate, secondary nitrate, mobile, industrial lead sources, dust, construction dust, biomass burning, fuel oil combustion and sea salt, were identified across the sampling sites. Secondary sulfate was the dominant source, contributing 35% of the total PM2.5 mass, and it showed relatively homogeneous temporal trends of daily source contribution in the study area. Mobile sources were found to be the second greatest contributor to PM2.5 mass in the large metropolitan cities, such as Tel Aviv, Hebron, and West and East Jerusalem. Other sources (i.e. industrial lead sources, construction dust, and fuel oil combustion) were closely related to local emissions within individual cities. This study demonstrates how international cooperation can facilitate air pollution studies that address regional air pollution issues and the incremental differences across cities in a common airshed. It also provides a model to study air pollution in regions with limited air quality monitoring capacity that have persistent and emerging air quality problems, such as Africa, South Asia and Central America.

Although plastic straws account for a small fraction of urban residue, they are also found in marine and coastal waste, raising concerns in the community and resulting in policies to curb or ban improper disposal. These policies are still little documented and discussed in the scientific literature. This review article aims at surveying, categorizing and analyzing existing regulations on the American continent (North, Central and South America and the Caribbean). The regulations were analyzed in terms of straw bans; obligations regarding the type of raw material used in manufacturing; accessibility-related exceptions to bans; and the adoption of environmental education measures. A total of 363 regulations enacted in 62.8% of American countries were examined, 37% of which need technical standards to support their requirements. In Central America and the Caribbean, it is primarily the regulations that provide environmental education. Locations with a strong beach tourism economy have enacted plastic straw regulations.

Since 2011, tropical beaches from Africa to Brazil, Central America, and the Caribbean have been inundated by tons of sargassum seaweed from a new equatorial source of pelagic sargassum in the Atlantic. In recent years the extraordinary accumulations of sargassum make this a nuisance algal bloom for tropical coasts. In 2018 satellite data indicated floating mats of sargassum that extended throughout the Caribbean to the northeast coast of Brazil with the highest percent coverage over the water yet recorded. A literature review suggests that Atlantic equatorial recirculation of seaweed mats combined with nutrients from several possible sources may be stimulating the growth and accumulations of sargassum. In the western equatorial recirculation area, new nutrient sources may include Amazon River floods and hurricanes; in the eastern equatorial recirculation area, nutrient sources that could sustain the sargassum blooms include coastal upwelling and Congo River freshwater and nutrients.

Concentrations of eight metals and metalloids (Pb, Cd, Cu, Zn, Mn, Se, Ni and As) were evaluated from 41 nesting females (blood) and 13 dead (tissues) Olive Ridley turtles (Lepidochelys olivacea), a species classified as vulnerable and also listed in Appendix I of the Convention of International Trade in Endangered Species (CITES). The mean blood, liver and kidney lead concentration were 0.02±0.01, 0.11±0.08 and 0.06±0.03μgg−1 ww respectively, values lower than other turtle species and locations, which it could be due to the gradual disuse of leaded gasoline in Mexico and Central America since the 1990s. Mean concentration of cadmium was 0.17±0.08 (blood), 82.88±36.65 (liver) and 150.88±110.99μgg−1 (kidney). To our knowledge, the mean renal cadmium levels found is the highest ever reported worldwide for any sea turtle species, while other six elements showed a concentration similar to other studies in sea turtles.

Chronic kidney disease of unknown etiology [CKDu] is a condition characterized by decline in kidney function and is not associated with diabetic nephropathy or hypertensive nephropathy. In this review, we have done a detailed literature analysis on CKDu in India, and then had a comparison with that of Mesoamerica and Sri Lanka. In India, CKDu became the second most common type of CKD after diabetic nephropathy. Silica was seen in the groundwater of both India and Sri Lanka, whereas in Mesoamerica silica exposure through particulate matter was seen among CKDu communities. DDE is a common agrochemical seen in both India and Sri Lanka. The risk factors vary from region to region and it is important to categorize CKDu population based on the risk factors to avoid misinterpretation of the condition as non-CKDu category and to evade further complications. More studies have to be conducted to reveal the detailed pathophysiological mechanisms and its relation with irrational exploitation of environmental resources.

Biomass burning from grassland, forests, and agricultural waste results in large amounts of gases and particles emitted to the atmosphere, which affect air quality, population health, crop development, and natural vegetation. Regional atmospheric circulations can transport those plumes of pollutants over hundreds of kilometers, affecting vulnerable environments such as those considered protected natural areas (PNAs). This study evaluates the spatiotemporal distribution of active fires detected, and associated emissions, in central and southern Mexico from satellite data between March and June 2017, to assess the impact of the smoke plumes on protected ecosystems. The arrival of smoke plumes to selected PNAs (both near large urban centers and in remote areas) is assessed using airmass forward trajectories from selected emission sources. The spatial distribution of the remotely derived aerosol optical depth confirms the regional impact of particle emissions from the observed fires on PNAs, particularly in central Mexico. The identified areas of high fire density are also associated with large coarse particle concentrations at the surface. Moreover, there is a significant contribution of organic carbon to the total coarse particle mass, 60% on average. Finally, while most of the impact in ambient pollution is observed in PNAs located close to the regions with active fires in southern Mexico and Central America, the long-range transport of smoke plumes reaching the USA was also confirmed.