The Institutional Care of Children. United Nations Department of Economic and Social Affairs

Ever growing populations in cities are associated with a major increase in road vehicles and air pollution. The overall high levels of urban air pollution have been shown to be of a significant risk to city dwellers. However, the impacts of very high but temporally and spatially restricted pollution, and thus exposure, are still poorly understood. Conventional approaches to air quality monitoring are based on networks of static and sparse measurement stations. However, these are prohibitively expensive to capture tempo-spatial heterogeneity and identify pollution hotspots, which is required for the development of robust real-time strategies for exposure control. Current progress in developing low-cost micro-scale sensing technology is radically changing the conventional approach to allow real-time information in a capillary form. But the question remains whether there is value in the less accurate data they generate. This article illustrates the drivers behind current rises in the use of low-cost sensors for air pollution management in cities, whilst addressing the major challenges for their effective implementation.

The rise of low-cost sensing for managing air pollution in cities

Most major cities around the world experience periods of elevated air pollution levels, which exceed international health-based air quality standards (Kumar et al., 2013). Although it is a global problem, some of the highest air pollution levels are found in rapidly expanding cities in India and China. The sources, emissions, transformations and broad effects of meteorology on air pollution are reasonably well accounted in air quality control strategies in many developed cities; however these key factors remain poorly constrained in the growing cities of countries with emerging economies. We focus here on Delhi, one of the largest global population centres, which faces particular air pollution challenges, now and in the future.

New directions: Air pollution challenges for developing megacities like Delhi

Urban river pollution in Bangladesh during last 40 years: potential public health and ecological risk, present policy, and future prospects toward smart water management.

We reviewed recent peer-reviewed literature on three categories of individual- and household-level interventions against air pollution: air purifiers, facemasks, and behavior change. High-efficiency particulate air/arresting (HEPA) filter air purifier use over days to weeks can substantially reduce fine particulate matter (PM2.5) concentrations indoors and improve subclinical cardiopulmonary health. Modeling studies suggest that the population-level benefits of HEPA filter air purification would often exceed costs. Well-fitting N95 and equivalent respirators can reduce PM2.5 exposure, with several randomized crossover studies also reporting improvements in subclinical cardiovascular health. The health benefits of other types of face coverings have not been tested and their effectiveness in reducing exposure is highly variable, depends largely on fit, and is unrelated to cost. Behavior modifications may reduce exposure, but there has been little research on health impacts. There is now substantial evidence that HEPA filter air purifiers reduce indoor PM2.5 concentrations and improve subclinical health indicators. As a result, their use is being recommended by a growing number of government and public health organizations. Several studies have also reported subclinical cardiovascular health benefits from well-fitting respirators, while evidence of health benefits from other types of facemasks and behavior changes remains very limited. In situations when emissions cannot be controlled at the source, such as during forest fires, individual- or household-level interventions may be the primary option. In most cases, however, such interventions should be supplemental to emission reduction efforts that benefit entire communities.

/pdf/individual-and-household-level-interventions-to-reduce-air-460738llfw.pdf

Individual- and Household-Level Interventions to Reduce Air Pollution Exposures and Health Risks: a Review of the Recent Literature.

https://cdn.sei.org/wp-content/uploads/2020/11/1-s2.0-s004896972034924x-main.pdf

In-car particulate matter exposure across ten global cities

The importance of water cannot be overstated. Not only it is essential for life, it is a vital resource for sustainable development. Water resource management is pivotal to ensure water security an...

Water, water, but not everywhere: analysis of shrinking water bodies using open access satellite data

Se estudio la concentracion de acido linoleico conjugado (CLA) de quince yogures de las marcas comerciales de mayor consumo y distribucion en el mercado colombiano, asi como su composicion en acidos grasos. La concentracion de CLA, expresada como mg de acido cis-9,trans-11 octadecadienoico/g de grasa y como mg de acido cis-9,trans-11 octadecadienoico/100 g de yogur oscilo entre 4,5 y 8,2 y entre 7,8 y 25,5, respectivamente. Los valores de CLA mas elevados (>6,0 mg/g de grasa) en los yogures evaluados, correspondieron a aquellos que contenian cultivo de yogur (Lactobacillus delbrueckii ssp. bulgaricus y Streptococcus salivarius ssp. thermophilus) y especies de Bifidobacterium y Lactobacillus. Los principales acidos grasos encontrados en las muestras estudiadas, fueron los acidos palmitico (10,7-21,2 mg/g de grasa), oleico (11,9-21,0 mg/g de grasa), estearico (16,1-37,4 mg/g de grasa), miristico (3,5-7,8 mg/g de grasa) y butirico (1,6-5,5 mg/g de grasa). Bajas relaciones de PUFA/SFA y de MUFA/SFA fueron encontradas, como es tipico en muestras de grasa lactea.

/pdf/contenido-de-acido-linoleico-conjugado-cla-y-composicion-de-2acxlulcey.pdf

Contenido de Ácido Linoleico Conjugado (CLA) y Composición de Ácidos Grasos en Algunos Yogures Comerciales de Colombia.

Resumen. Se estudió la concentración de ácido linoleico conjugado (CLA) de quince yogures de las marcas comerciales de mayor consumo y distribución en el mercado colombiano, así como su composición en ácidos grasos. La concentración de CLA, expresada como mg de ácido cis-9,trans-11 octadecadienoico/g de grasa y como mg de ácido cis-9,trans-11 octadecadienoico/100 g de yogur osciló entre 4,5 y 8,2 y entre 7,8 y 25,5, respectivamente. Los valores de CLA más elevados (>6,0 mg/g de grasa) en los yogures evaluados, correspondieron a aquellos que contenían cultivo de yogur (Lactobacillus delbrueckii ssp. bulgaricus y Streptococcus salivarius ssp. thermophilus) y especies de Bifidobacterium y Lactobacillus. Los principales ácidos grasos encontrados en las muestras estudiadas, fueron los ácidos palmítico (10,7-21,2 mg/g de grasa), oleico (11,9-21,0 mg/g de grasa), esteárico (16,1-37,4 mg/g de grasa), mirístico (3,5-7,8 mg/g de grasa) y butírico (1,6-5,5 mg/g de grasa). Bajas relaciones de PUFA/SFA y de MUFA/SFA fueron encontradas, como es típico en muestras de grasa láctea.

Jenny Carolina Martínez

Papers

In-car particulate matter exposure across ten global cities

Water, water, but not everywhere: analysis of shrinking water bodies using open access satellite data

Contenido de Ácido Linoleico Conjugado (CLA) y Composición de Ácidos Grasos en Algunos Yogures Comerciales de Colombia.

Conjugated linoleic acid (CLA) content and fatty acid composition of some commercial yogurts from Colombia.