Air Pollution and Environmental Justice in Latin America: Where Are We and How Can We Move Forward?

Particulate matter 2.5 accelerates aging: Exploring cellular senescence and age-related diseases

Exposure to Particulate matter 2.5 (PM2.5) accelerates aging, causing declines in tissue and organ function, and leading to diseases such as cardiovascular, neurodegenerative, and musculoskeletal disorders. PM2.5 is a major environmental pollutant and an exogenous pathogen in air pollution that is now recognized as an accelerator of human aging and a predisposing factor for several age-related diseases. In this paper, we seek to elucidate the mechanisms by which PM2.5 induces cellular senescence, such as genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, and mitochondrial dysfunction, and age-related diseases. Our goal is to increase awareness among researchers within the field of the toxicity of environmental pollutants and to advocate for personal and public health initiatives to curb their production and enhance population protection. Through these endeavors, we aim to promote longevity and health in older adults.

Critical Environmental Injustice: A Case Study Approach to Understanding Disproportionate Exposure to Toxic Emissions

Environmental justice research has focused on the distribution of environmental inequalities, such as proximity to landfills, across the U.S. and globally.

BACKGROUND

Public health research and environmental health research, specifically, have focused on toxic exposure-encompassing individuals or communities that are disproportionately exposed to contaminants that are harmful or potentially harmful to them. Yet, little research has applied critical environmental justice theory-characterized by the idea that marginalized communities need to be treated as indispensable rather than disposable-to the study of toxic exposure. To fill this gap, the current paper offers a case study approach applying critical environmental justice theory to the study of disproportionate and unequal exposure to toxic contaminants.

METHODS

This case study is of Kettleman City, a rural, unincorporated community in the heart of California's Central Valley (USA). This community experiences the co-location of environmental hazards, including residing at the intersection of two major highways and hosting a class I hazardous-waste landfill, which is one of the few licensed to accept PCBs. PCBs are a contaminant that has been linked with several adverse health outcomes, including cancers and low birthweight. Residents may also experience poor air quality from proximity to the highways.

RESULTS

This case highlights the uneven distribution of pollution and environmental degradation that may be shouldered by the community, along with their experiences of adverse health and social impacts. This analysis reveals the importance of incorporating a critical environmental justice perspective to unpack experiences of not only disproportionate exposure but also disproportionate procedural and recognitional inequality.

CONCLUSIONS

This research highlights the untapped potential of environmental justice to catalyze exposure science in challenging the unequal distribution of contaminants.

Air pollution and environmental epidemiological evidence in Chile: alerts for decision-makers and citizens

Air pollution in Chile presents unique challenges, exacerbated by inequalities and geographical and climatic diversity. Current policies have not succeeded in aligning air quality with international and national standards, nor have they significantly mitigated public health impacts, despite being more advanced than those in other Latin American countries. The evidence on the health damages caused by air pollution is compelling, showing harmful acute and chronic effects across various life stages. Yet, current measures do not effectively reduce exposure to pollutants. The monitoring network, which reports data from stationary and mobile sources, does not always detect early fugitive emissions and is limited to regulated pollutants, leaving areas without adequate monitoring coverage and without management plans for critical episodes outside of autumn and winter and for a reduced number of pollutants. In the context of climate change, which increases the frequency of forest fires, Chile is experiencing a deterioration of air quality, highlighting the need to expand critical episode management beyond the current Air Pollution Prevention and/or Atmospheric Decontamination Plans. Integrated intersectoral plans need to be improved and extended to address the high exposure to pollutants, due to the large number of people exposed, and a broad population health risks, including quality of life. Decarbonisation by 2040 based on the Sustainable Development Goals is an important pillar of the strategy, but a public debate is needed to establish additional actions for addressing environmental injustice, improving equity and reducing current exposure to air pollutants.

Ambient nitrogen dioxide in 47 187 neighbourhoods across 326 cities in eight Latin American countries: population exposures and associations with urban features

BACKGROUND

Health research on ambient nitrogen dioxide (NO2) is sparse in Latin America, despite the high prevalence of NO2-associated respiratory diseases in the region. This study describes within-city distributions of ambient NO2 concentrations at high spatial resolution and urban characteristics associated with neighbourhood ambient NO2 in 326 Latin American cities.

METHODS

We aggregated estimates of annual surface NO2 at 1 km2 spatial resolution for 2019, population counts, and urban characteristics compiled by the SALURBAL project to the neighbourhood level (ie, census tracts). We described the percentage of the urban population living with ambient NO2 concentrations exceeding WHO air quality guidelines. We used multilevel models to describe associations of neighbourhood ambient NO2 concentrations with population and urban characteristics at the neighbourhood and city levels.

FINDINGS

We examined 47 187 neighbourhoods in 326 cities from eight Latin American countries. Of the roughly 236 million urban residents observed, 85% lived in neighbourhoods with ambient annual NO2 above WHO guidelines. In adjusted models, higher neighbourhood-level educational attainment, closer proximity to the city centre, and lower neighbourhood-level greenness were associated with higher ambient NO2. At the city level, higher vehicle congestion, population size, and population density were associated with higher ambient NO2.

INTERPRETATION

Almost nine out of every ten residents of Latin American cities live with ambient NO2 concentrations above WHO guidelines. Increasing neighbourhood greenness and reducing reliance on fossil fuel-powered vehicles warrant further attention as potential actionable urban environmental interventions to reduce population exposure to ambient NO2.

FUNDING

Wellcome Trust, National Institutes of Health, Cotswold Foundation.

Methods in Public Health Environmental Justice Research: a Scoping Review from 2018 to 2021

PURPOSE OF REVIEW

The volume of public health environmental justice (EJ) research produced by academic institutions increased through 2022. However, the methods used for evaluating EJ in exposure science and epidemiologic studies have not been catalogued. Here, we completed a scoping review of EJ studies published in 19 environmental science and epidemiologic journals from 2018 to 2021 to summarize research types, frameworks, and methods.

RECENT FINDINGS

We identified 402 articles that included populations with health disparities as a part of EJ research question and met other inclusion criteria. Most studies (60%) evaluated EJ questions related to socioeconomic status (SES) or race/ethnicity. EJ studies took place in 69 countries, led by the US (n = 246 [61%]). Only 50% of studies explicitly described a theoretical EJ framework in the background, methods, or discussion and just 10% explicitly stated a framework in all three sections. Among exposure studies, the most common area-level exposure was air pollution (40%), whereas chemicals predominated personal exposure studies (35%). Overall, the most common method used for exposure-only EJ analyses was main effect regression modeling (50%); for epidemiologic studies the most common method was effect modification (58%), where an analysis evaluated a health disparity variable as an effect modifier. Based on the results of this scoping review, current methods in public health EJ studies could be bolstered by integrating expertise from other fields (e.g., sociology), conducting community-based participatory research and intervention studies, and using more rigorous, theory-based, and solution-oriented statistical research methods.

Assessing socioeconomic bias of exposure to urban air pollution: an autopsy-based study in São Paulo, Brazil

Background

The characterisation of individual exposure to air pollution in urban scenarios is a challenge in environmental epidemiological studies. We investigated if the city's pollution monitoring stations over or underestimate the exposure of individuals depending on their socioeconomic conditions and daily commuting times.

Methods

The amount of black carbon accumulated in the lungs of 604 deceased who underwent autopsy in São Paulo was considered as a proxy for PM₁₀. The concentrations of PM₁₀ in the residence of the deceased were estimated by interpolating an ordinary kriging model. These two-exposure metrics allowed us to construct an environmental exposure misclassification index ranging from -1 to 1. The association between the index and daily commuting, socioeconomic context index (GeoSES), and street density as predictors was assessed by means of a multilevel linear regression model.

Findings

With a decrease of 0^.1 units in GeoSES, the index increases, on average, by 0^.028 units and with an increase of 1 h in daily commuting, the index increases, on average, by 0^.022 units indicating that individual exposure to air pollution is underestimated in the lower GeoSES and in people with many hours spent in daily commuting.

Interpretation

Reduction of health consequences of air pollution demands not only alternative fuel and more efficient mobility strategies, but also should include profound rethink of cities.

Funding

São Paulo Research Foundation (FAPESP-13/21728-2) and National Council for Scientific and Technological Development (CNPq-304126/2015-2, 401825/2020-5).

Ambient nitrogen dioxide in 47,187 neighborhoods across 326 cities in eight Latin American countries: population exposures and associations with urban features

Background

Health research on ambient nitrogen dioxide (NO2) is sparse in Latin America, despite the high prevalence of NO2-associated respiratory diseases in the region. This study describes within-city distributions of ambient NO2 concentrations at high spatial resolution and urban characteristics associated with neighborhood ambient NO2 in 326 Latin American cities.

Methods

We aggregated estimates of annual surface NO2 at 1 km2 spatial resolution for 2019, population counts, and urban characteristics compiled by the SALURBAL project to the neighborhood level (i.e., census tracts). We described the percent of the urban population living with ambient NO2 levels exceeding WHO Air Quality Guidelines. We used multilevel models to describe associations of neighborhood ambient NO2 concentrations with population and urban characteristics at the neighborhood and city levels.

Findings

We examined 47,187 neighborhoods in 326 cities from eight Latin American countries. Of the ≈236 million urban residents observed, 85% lived in neighborhoods with ambient annual NO2 above WHO guidelines. In adjusted models, higher neighborhood-level educational attainment, closer proximity to the city center, and lower neighborhood-level greenness were associated with higher ambient NO2. At the city level, higher vehicle congestion, population size, and population density were associated with higher ambient NO2.

Interpretation

Almost nine out of every 10 residents of Latin American cities live with ambient NO2 concentrations above WHO guidelines. Increasing neighborhood greenness and reducing reliance on fossil fuel-powered vehicles warrant further attention as potential actionable urban environmental interventions to reduce population exposure to ambient NO2.

Funding

Wellcome Trust, National Institutes of Health, Cotswold Foundation.

Just Transition on air quality governance: a case study of heavy-duty diesel truck protests in Taiwan

Just Transitions are gaining attention in environmental research, and most studies have focused on climate change; however, the insights from this work may be usefully applied to the rarely discussed area in just transition studies. This article uses traditional dimensions of environmental and social justice, such as distributive, procedural, recognition, and restorative justice, to understand why heavy-duty diesel truck drivers fought back against stricter air pollution regulations while demanding destigmatization. The protest resulted in policy failure, and Taiwan's transition to cleaner, newer diesel trucks were halted. This study finds that the key social contextual factor in Taiwan's transportation industry was the labor relations of license-leasing. The drivers' protest began with a lack of procedural justice, and communication occurred only after the law was passed. There was insufficient regard for procedural justice, and although the drivers were concerned, the new rule would significantly impact their right to work and life. Furthermore, the drivers felt disrespected and even carried the stigma of creating environmental pollution. The article assumes that the results should be different if the governance mechanism can handle the key factor in a social context and make appropriate arrangements for the four dimensions of Just Transition. This argument may be relevant for other countries looking to transition from older diesel vehicles to cleaner vehicles through Just Transition.