Associations between socio-demographic characteristics and chemical concentrations contributing to cumulative exposures in the United States

Abstract

Association rule mining (ARM) has been widely used to identify associations between various entities in many fields. Although some studies have utilized it to analyze the relationship between chemicals and human health effects, fewer have used this technique to identify and quantify associations between environmental and social stressors. Socio-demographic variables were generated based on U.S. Census tract-level income, race/ethnicity population percentage, education level, and age information from the 2010-2014, 5-Year Summary files in the American Community Survey (ACS) database, and chemical variables were generated by utilizing the 2011 National-Scale Air Toxics Assessment (NATA) census tract-level air pollutant exposure concentration data. Six mobile- and industrial-source pollutants were chosen for analysis, including acetaldehyde, benzene, cyanide, particulate matter components of diesel engine emissions (namely, diesel PM), toluene, and 1,3-butadiene. ARM was then applied to quantify and visualize the associations between the chemical and socio-demographic variables. Census tracts with a high percentage of racial/ethnic minorities and populations with low income tended to have higher estimated chemical exposure concentrations (fourth quartile), especially for diesel PM, 1,3-butadiene, and toluene. In contrast, census tracts with an average population age of 40-50 years, a low percentage of racial/ethnic minorities, and moderate-income levels were more likely to have lower estimated chemical exposure concentrations (first quartile). Unsupervised data mining methods can be used to evaluate potential associations between environmental inequalities and social disparities, while providing support in public health decision-making contexts.

Environmental Justice in Industrially Contaminated Sites. A Review of Scientific Evidence in the WHO European Region

“…The analysis of abstracts of studies focusing on distributive justice worldwide showed that U.S. is the country with the largest number of published studies (N. 24, including two studies in the U.S.-Mexico borderlands), as expected [59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82]. Among the studies published outside the WHO European Region and not in the U.S., two were carried out in Australia [83,84], three in China [85,86,87], two in Latin America [88,89], and one in Canada [90], Ghana [91], India [92], and South Korea [93].…”

A Scoping Review of Capacity-Building Efforts to Address Environmental Justice Concerns

“…As articulated by Dr. Robert Bullard and other prominent scholars and leaders in the environmental justice (EJ) movement, "everyone is entitled to equal protection and equal enforcement of our environmental health, housing, land use, transportation, energy and civil rights laws and regulations" [1], in all the places "where we live, work, play, worship, and go to school" [1]. In the United States, the EJ movement has grown in response to systematic inequities in exposures to lead and air pollution; groundwater contamination and drinking water safety; close proximity to noxious facilities and nuclear plants; location of landfills, incinerators, and abandoned toxic waste sites; placement of transportation thoroughfares; illegal dumping; superfund sites; and unequal enforcement of environmental laws [2][3][4][5][6][7]. Today, EJ also includes issues of immigrant and indigenous rights [8], climate change [9], green space [10], refurbishment of brownfields [11], and food justice [12].…”

“…The patterning of environmental inequity has received great attention and many studies have highlighted the pervasive nature of race as one of the most critically important predictors of exposure to environmental hazards [13][14][15]. Numerous research disciplines including American studies [16], economics [13], environmental health [5,6], epidemiology [4], sociology [1,17], philosophy [18], and politics [19,20] have documented discriminatory practices and the inequities of toxic waste distribution among low-income communities and communities of color. The explicit and implicit discrimination in environmental policymaking-the targeting of communities of color for toxic waste facilities, and the systematic under-resourcing and overburdening of marginalized communities-have been collectively termed environmental racism [21] and have plagued the United States for decades [3].…”

Cumulative Risk and Impact Modeling on Environmental Chemical and Social Stressors

“…To account for non-chemical stressors in the process of exposure and dose estimates, the Average Daily Dose model [27], was linked to multiple social indicators and applied to examine dose estimates on both the U.S. nationwide census tract-level and community-wise local scale [28]. In addition, association rule mining [29], an unsupervised machine learning method, was also utilized to evaluate associations between social factors and environmental chemical concentrations relevant to cumulative impacts in the U.S. [30]. …”