Scorching Excessive Heat + High Pollution Advisories > There Are Consequences

News about the weather recently started with words like 'Scorching heat' - completely omitting serious health consequences including death from dangerously high levels of ozone and particulate matter in the air, while advising people with respiratory issues to simply stay indoors and don't drive . . . the Arizona Department of Environmental Quality issues "alerts" for unhealthy air all the time and year-round while Maricopa County has consistently failed to meet federal requirements for clean air year-after-year. . . are we too dumb and happy living in Maricopa County?

Here are the conclusions from a somewhat detailed, technical, well-researched report from
2000-2008 by Environmental Health Perspectives, part of the National Institute for Health
Neighborhood Effects on Heat Deaths: Social and Environmental Predictors of Vulnerability in Maricopa County, Arizona
Research article volume 121 | Issue 2 | February 2013

Figure 1 – HVI scores (using a method modified from Reid et al. 2009) mapped for 2,081 census block groups (CGBs) in Maricopa County, Arizona. Higher scores represent higher vulnerability. The map inset in the lower right corner indicates the urbanized area of Maricopa County (red box) shown in the larger map. The county, which also contains a much larger area of uninhabited desert and sparse settlement, is outlined in blue. The urbanized area covers all the cities and all but one of the major towns in the county. Residences of only four people who died from heat exposure were located outside the urbanized area (green circles in inset).
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Figure 2 – Univariate analysis of the LISA-identified clusters of census block groups (CBGs) in Maricopa County, Arizona, with similar or dissimilar HVI scores (p-value ≤ 0.05). High/high areas in the map are clusters of neighboring CBGs with uniformly high vulnerability scores; low/low areas are clusters with low vulnerability scores; low/high areas represent a CBG with a low vulnerability score neighbored by high vulnerability CBGs; high/low areas represent a CBG with a high vulnerability score neighbored by low vulnerability CBGs. Entries in the legend (next to the colored boxes) also show the percentages of 2000–2008 heat-related decedents who were residents in each type of cluster.
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In the present study, we investigated neighborhood effects on heat exposure deaths in Maricopa County, Arizona, over a 9-year period (2000–2008). Extremely high temperatures occur almost daily for 6 months a year in this desert climate. The decedents were identified by the county health department using a surveillance system designed specifically to detect deaths caused by or related to environmental (weather-related) heat. Our question was “What characteristics of urban neighborhoods affect the risk of residents dying from extreme heat?”
Many studies on urban heat-related mortality examine individual-specific risk factors.
Commonly identified physiological risks include

• advanced or young age,
• underlying disease, disability, and pregnancy.
• Cardiovascular disease and several other illnesses are risk factors for heat-related death
• Deaths from heat exposure also occur among people who lack access to cool environments or are physically active in hot weather
• Living in poverty is a key individual risk factor for death related to heat because it decreases the odds of access to medical care and protective resources

Neighborhoods are “ecological units nested within successively larger communities” and neighborhood effects on human development and life cycle events, individual behavior, social outcomes, and health risks have long been studied in the social and health sciences

• Many indicators of poor health, such as low birth weight, obesity, and coronary heart disease are spatially clustered within neighborhoods.
• Socioeconomic context is important because many poor neighborhoods lack institutional capacities for education, health care, and employment and have poor quality housing.
• Many minorities live in low-income areas with high levels of social isolation and concentrated disadvantage

We estimated the neighborhood effects of population characteristics and features of the built and natural environments on deaths due to heat exposure in Maricopa County, Arizona (2000–2008).
Spatial patterns showed substantial variability between neighborhoods in vulnerability to heat, odds of residents dying from heat exposure, and locations of vulnerable neighborhood clusters.
Many inner-city neighborhoods had higher vulnerability scores and more deaths, whereas higher neighborhood income and education, younger white populations, greener landscapes, AC, and cooler microclimates in suburban neighborhoods were associated with reduced heat vulnerability and fewer deaths.
Heat deaths of homeless persons were reported primarily in the inner city. Many decedents, however, lived in neighborhoods with lower vulnerability scores and, therefore, place-based indicators of vulnerability are complements and not substitutes for person-level risk variables.
Surface temperature [from highways and "heat islands" like parking lots and unvegetated lands] might be used as a single indicator in Maricopa County to identify the most heat-vulnerable neighborhoods.
However, more attention to the socioecological complexities of climate mitigation and adaptation is a high public health priority.
There are major local challenges ahead in preventing heat-related deaths under global regimes of climate change and urbanization.