The first hypothesis we test is that study area facilities and pollution are distributed “inequitably” according to race, Hispanic ethnicity, and income. shows that neither black respondent nor percent black in the Census tract is significantly associated with average number of facilities or average waste generated. However, Hispanic respondent, percent Hispanic, percent poverty, and respondent’s family income are all weakly correlated with average number of facilities and average waste generated in the expected directions. Thus, respondents with higher incomes live in tracts with lower average facility and average waste levels than do respondents with lower incomes (r = −.044 and r = −.046; p < .05); Hispanic respondents live in tracts with higher average facility and average waste levels than do non-Hispanic respondents (r = .113 and r = .088, p < .001); and as the percentage of Hispanics in a Census tract increases, so too do the number of facilities and pounds of waste within a ¼-kilometer radius of the average tract cell (r = .151 and r = .128, p < .001). Finally, as the proportion of people in a tract living in poverty increases, so too do the number of facilities and pounds of waste within a ¼-kilometer radius of the average tract cell (r = .088 and r = .090, p < .001).
Bivariate Relationships between Outcome Measures, Facility Presence, Pounds of Waste, and Control Variables (N = 1,210)
Thus, while we find some evidence of differential proximity to facilities and waste, particularly according to Hispanic ethnicity and percent Hispanic in a tract, the significant relationships are relatively weak. This is typical of much, but by no means all, environmental inequality research, which finds consistently significant relationships between neighborhood income and environmental hazard presence, but inconsistent and often weak statistical associations between race, Hispanic ethnicity, and environmental hazard presence (Anderton et al. 1994
; Oakes, Anderton, and Anderson 1996
; Yandle and Burton 1996
; Szasz and Meuser 1997
; Sadd et al. 1999
also shows that industrial activity is weakly but consistently correlated with disorder, depressive symptoms, and powerlessness. Individuals who live in tracts with high average facility levels report more symptoms of depression (r = .051, p < .05), perceive their neighborhoods to have greater levels of disorder (r = .084, p < .01), and feel that they have less control over their lives (r = .069, p < .01) than do individuals who live in tracts with lower average facility levels. Likewise, individuals who live in Census tracts with high levels of average waste report higher levels of depression symptoms (r = .050, p < .05), higher levels of disorder (r = .071, p < .01), and lower levels of control (r = .068, p < .01) than do individuals who live in tracts with lower average waste levels.
Although these results support our hypothesis that industrial activity is positively associated with perceptions of disorder, feelings of personal powerlessness, and symptoms of depression, they may be spurious. In order to test the hypothesis that residential proximity to environmental hazards is positively associated with feelings of disorder, net of individual and other neighborhood characteristics, we regress disorder on our two measures of industrial threat, controlling for neighborhood poverty, neighborhood stability, the Chicago metropolitan area dummy, and a set of respondent characteristics listed at the bottom of . Model 1 presents the regression for average number of facilities, and model 2 presents a regression for average waste.
Ordinary Least Squares Regression Analyses of Disorder Regressed on Facility Presence, Pounds of Waste, and Control Variables (N = 1,210)
shows us that the relationship between disorder and industrial activity is curvilinear, regardless of which indicator of industrial activity we use. Average number of facilities and average waste are positively associated with perceptions of social disorder until the relationship plateaus, when the average number of facilities in a tract equals .482 in model 1, and average waste equals 3,087,541 pounds in model 2.9
Since less than 1 percent of the respondents in the study area lived in tracts with a higher average facility level than .482, and since only one respondent lived in a tract with a higher average waste level than 3 million pounds, it is safe to conclude that the relationship between industrial activity and perceptions of social disorder is positive for the vast majority of respondents. Moreover, standardized coefficients reveal that the industrial activity indicators are more strongly associated with disorder than are neighborhood stability and any of the individual-level controls (the standardized coefficients for the individual-level controls are available from the authors upon request). These results provide strong support for the hypothesis that residential proximity to industrial activity is positively associated with perceived disorder.
tests the hypothesis that residential proximity to industrial activity is positively associated with feelings of powerlessness and that this association is mediated by perceptions of disorder. Models 1 and 2 do this for average number of facilities, and models 3 and 4 do this for average waste. Model 1 demonstrates that controlling for individual and neighborhood characteristics, but not disorder, there is a positive linear
relationship between average number of facilities and perceived powerlessness (b = .339, p
The significant association between average waste and perceived powerlessness (model 3) is positive until average waste equals 2,847,000 pounds and becomes negative thereafter. Only one respondent in the study area lives in a tract with average waste levels greater than 2,847,000 pounds.
Ordinary Least Squares Regression Analyses of Powerlessness Regressed on Facility Presence, Pounds of Waste, and Control Variables (N = 1,210)
When we include perceived disorder in the regression equation, the association between average number of facilities and perceived powerlessness becomes only marginally significant (model 2), as does the association between average waste and perceived powerlessness (model 4). These findings are consistent with our prediction that the relationship between industrial activity and powerlessness is at least partially indirect, with industrial activity leading to perceptions of disorder that in turn lead individuals to feel powerless to control their lives.
tests the hypothesis that industrial activity is positively associated with depression and that this relationship is mediated by perceived powerlessness and disorder. Model 1 demonstrates that controlling for individual and neighborhood characteristics, but not perceived disorder and powerlessness, the relationship between average number of facilities and depressive symptoms is curvilinear, with the positive effect of facility presence tapering off at an average of .388 facilities in a tract. Only 1 percent of residents live in tracts with more than this level of exposure. This relationship is no longer significant, however, once perceived disorder and powerlessness are stepped into the equation (model 2). Results not reported here demonstrate that when powerlessness and disorder are stepped into the model individually, they each contribute about equally to explaining the relationship between average number of facilities and symptoms of depression.
Ordinary Least Squares Regression Analyses of Depression Regressed on Facility Presence, Pounds of Waste, and Control Variables (N = 1,210)
The results are quite different for average waste, which has a positive linear relationship with depressive symptoms both when perceived disorder and powerlessness are left out of the equation (model 3, b = .003, p < .05) and when they are included in the equation (model 4, b = .003, p < .05). Thus, as the average waste in a tract increases, so too do the number of depressive symptoms respondents report experiencing.
Finally, we test the hypothesis that the relationship between industrial activity and psychological well-being varies according to respondent income and minority status. To test this hypothesis, we calculated interaction terms between each of the two measures of industrial activity and the black respondent, Hispanic respondent, and respondent income variables. We then entered the interaction terms individually into the final models presented in through .
The interaction results show that high levels of waste production result in fewer depressive symptoms (b = −.0007, p < .01) and lower levels of powerlessness (b = −.0002, p < .05) among higher income respondents than among lower income respondents and in more depressive symptoms (b = .013, p < .001) and a greater sense of powerlessness (b = .005, p < .05) among Hispanic respondents than among non-Hispanic respondents. Hispanic respondents are also more likely than non-Hispanic respondents to describe neighborhoods with high average facility presence levels as being disorderly (b = 1.540, p < .01). Finally, high levels of waste production produce a greater sense of powerlessness among black respondents than white respondents (b = .073, p < .05).