Environmental signature and health risk assessment of polybrominated diphenyl ethers (PBDEs) emitted from a landfill fire in Santiago de Chile.

Polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in building materials, electronics, furnishings, vehicles, airplanes, plastics, polyurethane foams, and textiles for many years. Currently, the primary commercial mixtures, penta-, octa-, and deca-BDE, are globally restricted. Still, products containing PBDEs are expected to impact waste management and the environment for many years. In January 2016, an open fire in the Santa Marta landfill close to Santiago de Chile affected the city and surroundings. The fire caused several acute health effects and an increase in emergency hospitalizations. We measured PBDE levels in the areas affected by the fire in the air (gaseous and particulate) and soil, and PBDE emissions were estimated using a dispersion model. The results showed an increase in PBDE concentrations by a factor of 2-4 one day after the start of the fire. However, PBDE concentrations measured after the fire in PM10 and the gas phase were considered low compared to other regions. Interestingly, PBDEs' patterns differed across the sites; however, BDE209 was the dominant congener for all environmental matrices. A preliminary risk assessment was conducted using the daily exposure dose (DED) by air inhalation estimation. The results showed low DED values for adults and children and suggested no direct health risk due to PBDE exposure. This study brings new data useful for future solid waste management initiatives in the country.

Aplicabilidad de la Predicción de Moyers 75% en pacientes Mapuche-Hulliche, Chile / Applicability of the Moyers prediction tables at 75% on Mapuche-Huilliche patients, Chile

Objetivo: determinar aplicabilidad del método Moyers 75% en población mapuche huilliche, Chile. Material y metodos: estudio descriptivo observacional se evaluó la predicción de Moyers nivel 75% en una población Mapuche Huilliche entre los 11 y 17 años de edad (25 hombres y 25 mujeres). Se determinó la suma de incisivos inferiores y la sumatoria de caninos y premolares de cada hemiarcada comparando con los valores predictivos. Resultados: Mayor número de casos en el rango 23.5 mm a 25.2 mm en la suma de incisivos inferiores, 60% de la muestra. La suma entre caninos y premolares presentó un promedio en el maxilar de 23.7 mm en hombres y 23.1 mm en mujeres y en la mandíbula un promedio de 22.9 mm en hombres y 22.1 mm en mujeres. Se encontró una discrepancia negativa de 60% en hombres y de un 40% en mujeres. En mujeres la discrepancia positiva superó a las negativas con porcentajes de 88% y 8%, significativamente. Conclusión:El método Moyers 75% es aplicable en hombres para ambos maxilares y parcialmente en mujeres huilliches.

Objective. To determine the applicability of the Moyers prediction tables at 75% on patients from the Mapuche-Huilliche population, Chile. Materials and Methods. A descriptive, observational study which evaluated the Moyers prediction tables at 75% in a Mapuche-Huilliche population aged between 11 and 17(25 men and 25 women). The sum of the lower incisors, and the sum of the canines and premolars of each quadrant was compared with each of the predictive values. Results. Increased number of cases in the range from 23.5 mm to 25.2 mm in the sum of lower incisors, which represent 60% of the sample. The sum of canines and premolars showed in maxilla a mean of 23.7 mm in men and 23.1 mm in women, and in mandiblea mean of 22.9 mm in men and 22.1 mm in women. A negative discrepancy of 60% was found in men and of 40% in women. For women, the positive discrepancysignificantly exceeded the negative discrepancies with percentages of 88% and 8%. Conclusions. The Moyers method at 75% was applicable in maxilla and mandible on Huilliche men, and partially applicable on women of the same ethnic group.

Estimating the health benefits from natural gas use in transport and heating in Santiago, Chile.

Chilean law requires the assessment of air pollution control strategies for their costs and benefits. Here we employ an online weather and chemical transport model, WRF-Chem, and a gridded population density map, LANDSCAN, to estimate changes in fine particle pollution exposure, health benefits, and economic valuation for two emission reduction strategies based on increasing the use of compressed natural gas (CNG) in Santiago, Chile. The first scenario, switching to a CNG public transportation system, would reduce urban PM2.5 emissions by 229 t/year. The second scenario would reduce wood burning emissions by 671 t/year, with unique hourly emission reductions distributed from daily heating demand. The CNG bus scenario reduces annual PM2.5 by 0.33 µg/m³ and up to 2 µg/m³ during winter months, while the residential heating scenario reduces annual PM2.5 by 2.07 µg/m³, with peaks exceeding 8 µg/m³ during strong air pollution episodes in winter months. These ambient pollution reductions lead to 36 avoided premature mortalities for the CNG bus scenario, and 229 for the CNG heating scenario. Both policies are shown to be cost-effective ways of reducing air pollution, as they target high-emitting area pollution sources and reduce concentrations over densely populated urban areas as well as less dense areas outside the city limits. Unlike the concentration rollback methods commonly used in public policy analyses, which assume homogeneous reductions across a whole city (including homogeneous population densities), and without accounting for the seasonality of certain emissions, this approach accounts for both seasonality and diurnal emission profiles for both the transportation and residential heating sectors.