Impacts of residential indoor air quality and environmental risk factors on adult asthma-related health outcomes in Chicago, IL.

BACKGROUND: Residential environments are known to contribute to asthma. OBJECTIVE: To examine the joint impacts of exposures to residential indoor and outdoor air pollutants and housing risk factors on adult asthma-related health outcomes. METHODS: We analyzed >1-year of data from 53 participants from 41 homes in the pre-intervention period of the Breathe Easy Project prior to ventilation and filtration retrofits. Health outcomes included surveys of asthma control, health-related quality of life, stress, and healthcare utilizations. Environmental assessments included quarterly measurements of indoor and outdoor pollutants (e.g., HCHO, CO, CO2, NO2, O3, and PM), home walk-throughs, and surveys of environmental risk factors. Indoor pollutant concentrations were also matched with surveys of time spent at home to estimate indoor pollutant exposures. RESULTS: Cross-sectional analyses using mixed-effects models indicated that lower annual average asthma control test (ACT) scores were associated (p < 0.05) with higher indoor NO2 (concentration/exposure: ß = -2.42/-1.57), indoor temperature (ß = -1.03 to -0.94), and mold/dampness (ß = -3.09 to -2.41). In longitudinal analysis, lower ACT scores were also associated (p < 0.05) with higher indoor NO2 concentrations (ß = -0.29), PM1 (concentration/exposure: ß = -0.12/-0.24), PM2.5 (concentration/exposure: ß = -0.12/-0.26), and PM10 (concentration/exposure: ß = 10.14/-0.28). Emergency department visits were associated with poorer asthma control [incidence rate ratio (IRR) = 0.84; p < 0.001], physical health (IRR = 0.95; p < 0.05), mental health (IRR = 0.95; p < 0.05), higher I/O NO2 ratios (IRR = 1.30; p < 0.05), and higher indoor temperatures (IRR = 1.41; p < 0.05). SIGNIFICANCE: Findings suggest that residential risk factors, including indoor air pollution (especially NO2 and particulate matter), higher indoor temperature, and mold/dampness, may contribute to poorer asthma control. IMPACT: This study highlights the importance of residential indoor air quality and environmental risk factors for asthma control, health-related quality of life, and emergency department visits for asthma. Two timescales of mixed models suggest that exposure to indoor NO2 and particulate matter, higher indoor temperature, and mold/dampness was associated with poorer asthma control. Additionally, emergency department visits were associated with poorer asthma control and health-related quality of life, as well as higher I/O NO2 ratios and indoor temperatures. These findings deepen our understanding of the interrelationships between housing, air quality, and health, and have important implications for programs and policy.

Indoor air quality impacts of residential mechanical ventilation system retrofits in existing homes in Chicago, IL.

Mechanical ventilation systems are used in residences to introduce ventilation air and dilute indoor-generated pollutants. A variety of ventilation system types can be used in home retrofits, influencing indoor air quality (IAQ) in different ways. Here we describe the Breathe Easy Project, a >2-year longitudinal, pseudo-randomized, crossover study designed to assess IAQ and adult asthma outcomes before and after installing residential mechanical ventilation systems in 40 existing homes in Chicago, IL. Each home received one of three types of ventilation systems: continuous exhaust-only, intermittent powered central-fan-integrated-supply (CFIS), or continuous balanced system with an energy recovery ventilator (ERV). Homes with central heating and/or cooling systems also received MERV 10 filter replacements. Approximately weeklong field measurements were conducted at each home on a quarterly basis throughout the study to monitor environmental conditions, ventilation operation, and indoor and outdoor pollutants, including size-resolved particles (0.3-10 µm), ozone (O3), nitrogen dioxide (NO2), carbon dioxide (CO2), carbon monoxide (CO), and indoor formaldehyde (HCHO). Mean reductions in indoor/outdoor (I/O) ratios across all systems after the intervention were approximately 12% (p = 0.001), 10% (p = 0.008), 42% (p < 0.001), 39% (p = 0.002), and 33% (p = 0.007), for CO2, NO2, and estimated PM1, PM2.5, and PM10, respectively. There was a reduction in I/O ratios for all measured constituents with each type of system, on average, but with varying magnitude and levels of statistical significance. The magnitudes of mean differences in I/O pollutant concentrations ratios were generally largest for most pollutants in the homes that received continuous balanced with ERV and smallest in the homes that received intermittent CFIS systems, with apparent benefits to providing ventilation continuously rather than intermittently. All ventilation system types maintained similar indoor temperatures during pre- and post-intervention periods.

The Impact of Low-Level Lead Toxicity on School Performance among Hispanic Subgroups in the Chicago Public Schools.

BACKGROUND: Environmental lead exposure detrimentally affects children's educational performance, even at very low blood lead levels (BLLs). Among children in Chicago Public Schools (CPS), the severity of the effects of BLL on reading and math vary by racial subgroup (White vs. Hispanic vs. non-Hispanic Black). We investigated the impact of BLL on standardized test performance by Hispanic subgroup (Mexican, Puerto Rican, and Other Hispanic). METHODS: We examined 12,319 Hispanic children born in Chicago between 1994 and 1998 who were tested for BLL between birth and 2006 and enrolled in the 3rd grade at a CPS school between 2003 and 2006. We linked the Chicago birth registry, the Chicago Blood Lead Registry, and 3rd grade Illinois Standard Achievement Test (ISAT) scores to examine associations between BLL and school performance. Primary analyses were restricted to children with BLL below 10 µg/dL (0.483 µmol/L). RESULTS: BLLs below 10 µg/dL (0.483 µmol/L) were inversely associated with reading and math scores in all Hispanic subgroups. Adjusted Relative Risks (RRadj) and 95% confidence intervals (CI) for reading and math failure were 1.34 (95% CI = 1.25, 1.63) and 1.53 (95% CI = 1.32, 1.78), respectively, per each additional 5 µg/dL of lead exposure for Hispanic children; RRadj did not differ across subgroups. We estimate that 7.0% (95% CI = 1.8, 11.9) of reading and 13.6% (95% CI = 7.7, 19.2) of math failure among Hispanic children can be attributed to exposure to BLLs of 5-9 µg/dL (0.242 to 0.435 µmol/L) vs. 0-4 µg/dL (0-0.193 µmol/L). The RRadj of math failure for each 5 µg/dL (0.242 µmol/L) increase in BLL was notably (p = 0.074) stronger among black Puerto Rican children (RRadj = 5.14; 95% CI = 1.65-15.94) compared to white Puerto Rican children (RRadj = 1.50; 95% CI = 1.12-2.02). CONCLUSIONS: Early childhood lead exposure is associated with poorer achievement on standardized reading and math tests in the 3rd grade for Mexican, Puerto Rican, and Other Hispanic children enrolled in Chicago Public Schools. While we did not see interactions between BLL and ISAT performance by Hispanic subgroup, the stronger association between BLL and math failure for Black Puerto Rican children is intriguing and warrants further study.

The impact of low-level lead toxicity on school performance among children in the Chicago Public Schools: a population-based retrospective cohort study.

BACKGROUND: Environmental lead exposure poses a risk to educational performance, especially among poor, urban children. Previous studies found low-level lead exposure was a risk factor for diminished academic abilities, however, this study is distinct because of the very large sample size and because it controlled for very low birth weight and early preterm birth-two factors closely associated with lower academic performance. In this study we examined the association between lead concentration in whole blood (B-Pb) of Chicago Public School (CPS) children and their performance on the 3(rd) grade Illinois Standard Achievement Tests (ISAT) reading and math scores. METHODS: We examined 58,650 children born in Chicago between 1994 and 1998 who were tested for blood lead concentration between birth and 2006 and enrolled in the 3(rd) grade at a CPS school between 2003 and 2006. We linked the Chicago birth registry, the Chicago Blood Lead Registry, and 3(rd) grade ISAT scores to examine associations between B-Pb and school performance. RESULTS: After adjusting for other predictors of school performance including poverty, race/ethnicity, gender, maternal education and very low birth weight or preterm-birth, we found that B-Pbs below 10 µg/dL were inversely associated with reading and math scores in 3(rd) grade children. For a 5 µg/dL increase in B-Pb, the risk of failing increased by 32% for reading (RR = 1.32, 95%CI = 1.26, 1.39) and math (RR = 1.32, 95%CI = 1.26, 1.39). The effect of lead on reading was non-linear with steeper failure rates at lower B-Pbs. We estimated that 13% of reading failure and 14.8% of math failure can be attributed to exposure to blood lead concentrations of 5 to 9 vs. 0 to 4 µg/dL in Chicago school children. CONCLUSIONS: Early childhood lead exposure is associated with poorer achievement on standardized reading and math tests in the third grade, even at very low B-Pbs. Preventing lead exposure in early childhood is critical to improving school performance.

Moving into green healthy housing.

BACKGROUND: Green building systems have proliferated but health outcomes and associated costs and benefits remain poorly understood. OBJECTIVE: To compare health before and after families moved into new green healthy housing with a control group in traditionally repaired housing. DESIGN AND SETTING: Mixed methods study in 3 Chicago housing developments. PARTICIPANTS: Public housing and low-income subsidized households (n = 325 apartments with 803 individuals). MAIN OUTCOME MEASURES: Self-reported health status, visual assessment of housing condition, indoor air sampling, and Medicaid expenditure and diagnostic data. Medicaid expenditures and International Classification of Diseases, Ninth Revision codes were modeled using a generalized linear model with γ distribution and log-link. RESULTS: Housing conditions and self-reported physical and mental health improved significantly in the green healthy housing study group compared with both the control group and the dilapidated public housing from which the residents moved, as did hay fever, headaches, sinusitis, angina, and respiratory allergy. Asthma severity measured by self-reported lost school/work days, disturbed sleep, and symptoms improved significantly, as did sadness, nervousness, restlessness, and child behavior. Medicaid data in this exploratory study were inconclusive and inconsistent with self-reported health outcomes and visual assessment data on housing quality but hold promise for future investigation. Possible sources of bias in the Medicaid data include older age in the study group, changes in Medicaid eligibility over time, controlling for Medicaid costs in an urban area, and the increased stress associated with moving, even if the move is into better housing. CONCLUSION: The mixed method approach employed here describes the complex relationships among self-reported health, housing conditions, environmental measures, and clinical data. Housing conditions and self-reported physical and mental health improved in green healthy housing. Health care cost savings in Medicaid due to improved housing could not be quantified here but hold promise for future investigations with larger cohorts over a longer follow-up period.

Lead and other heavy metals in dust fall from single-family housing demolition.

OBJECTIVE: We measured lead and other heavy metals in dust during older housing demolition and effectiveness of dust suppression. METHODS: We used American Public Housing Association Method 502 and U.S. Environmental Protection Agency Methods SW3050B and SW6020 at 97 single-family housing demolition events with intermittent (or no) use of water to suppress dust at perimeter, non-perimeter, and locations without demolition, with nested mixed modeling and tobit modeling with left censoring. RESULTS: The geometric mean (GM) lead dust fall during demolition was 6.01 micrograms of lead per square foot per hour (µg Pb/ft(2)/hour). GM lead dust fall was 14.18 µg Pb/ft(2)/hour without dust suppression, but declined to 5.48 µg Pb/ft(2)/hour (p=0.057) when buildings and debris were wetted. Significant predictors included distance, wind direction, and main street location. At 400 feet, lead dust fall was not significantly different from background. GM lead concentration at demolition (2,406 parts per million [ppm]) was significantly greater than background (GM=579 ppm, p=0.05). Arsenic, chromium, copper, iron, and manganese demolition dust fall was significantly higher than background (p<0.001). Demolition of approximately 400 old housing units elsewhere with more dust suppression was only 0.25 µg Pb/ft(2)/hour. CONCLUSIONS: Lead dust suppression is feasible and important in single-family housing demolition where distances between houses are smaller and community exposures are higher. Neighbor notification should be expanded to at least 400 feet away from single-family housing demolition, not just adjacent properties. Further research is needed on effects of distance, potential water contamination, occupational exposures, and water application.

The relationship of housing and population health: a 30-year retrospective analysis.

OBJECTIVE: We analyzed the relationship between health status and housing quality over time. METHODS: We combined data from two nationally representative longitudinal surveys of the U.S. population and its housing, the National Health and Nutrition Examination Survey and the American Housing Survey, respectively. We identified housing and health trends from approximately 1970 to 2000, after excluding those trends for which data were missing or where we found no plausible association or change in trend. RESULTS: Changes in housing include construction type, proportion of rental versus home ownership, age, density, size, moisture, pests, broken windows, ventilation and air conditioning, and water leaks. Changes in health measures include asthma, respiratory illness, obesity and diabetes, and lead poisoning, among others. The results suggest ecologic trends in childhood lead poisoning follow housing age, water leaks, and ventilation; asthma follows ventilation, windows, and age; overweight trends follow ventilation; blood pressure trends follow community measures; and health disparities have not changed greatly. CONCLUSIONS: Housing trends are consistent with certain health trends over time. Future national longitudinal surveys should include health, housing, and community metrics within a single integrated design, instead of separate surveys, in order to develop reliable indicators of how housing changes affect population health and how to best target resources. Little progress has been made in reducing the health and housing disparities of disadvantaged groups, with the notable exception of childhood lead poisoning caused by exposure to lead-based paint hazards. Use of these and other data sets to create reliable integrated indicators of health and housing quality are needed.

Lead dustfall from demolition of scattered site family housing: developing a sampling methodology.

BACKGROUND: Over 3000 older homes containing lead-based paint are demolished in Chicago each year. While previous studies investigating large multifamily housing demolitions have shown high levels of lead in dustfall, dispersed single-family housing demolition have yet to be assessed. Presently, no standards exist to regulate the extent of lead dustfall from housing demolition. OBJECTIVES: We studied ten residences in Chicago undergoing demolition and debris removal and compared dustfall rates to five standing homes from March to October 2006. METHODS: Dustfall was measured using a modification of APHA Method 502; samplers consisted of plastic buckets filled with 1l of deionized water, elevated to breathing zone height and placed around the demolition site perimeter. Laboratory analysis consisted of filtration, acid digestion and analysis by ICP/MS. RESULTS: During demolition, the geometric mean lead dustfall (n=43 at 10 locations) was 64.1 microgPb/m(2)/h (range: 1.3-3902.5), while the geometric mean lead dustfall for areas with no demolition (n=18 at 6 locations) was 12.9 microgPb/m(2)/h (range: 1.8-54.5). This difference was highly statistically significant (p=0.0004). When dust suppression measures were used, dustfall lead levels were lower, although the difference was not statistically significant. The geometric mean lead dustfall with dust suppression (n=25 at five locations) and without (n=22 at six locations) was 48 Pbmicrog/m(2)/h and 74.6 microgPb/m(2)/h, respectively. CONCLUSION: Demolition dustfall lead levels are much higher than background levels of lead during demolition of single-family housing and may constitute a yet uncharacterized but important source of lead exposure to nearby residents. Simple dust suppression methods are likely to reduce the contamination considerably.

Street corner hazard surveillance and health intervention among Chicago day laborers.

Day laborers in Chicago are often hired for hazardous jobs and have little access to basic health care. In this study, the researchers offered tetanus vaccinations and blood lead tests to workers waiting on street corners, who then completed a survey on hazardous job tasks (N = 92). All participants were male, 97% were foreign-born, and 93% had performed demolition and rehabilitation, window removal and installation, or paint removal in the previous month. Most were not current with tetanus immunization. The geometric mean blood lead level was 3.8 mug/dL. Nonparametric statistical analysis showed a significant association (p < .05) between blood lead level and country of origin. The results demonstrate the feasibility of hazard surveillance and health intervention at street corner hiring sites.

Identifying housing that poisons: a critical step in eliminating childhood lead poisoning.

The purpose of our study was to develop a method to identify and prioritize "high-risk" buildings in Chicago that could be targeted for childhood lead poisoning prevention activities. We defined "high-risk" buildings as those where multiple children younger than 6 years with elevated blood lead levels (BLLs) had lived and where lead hazards were previously identified on environmental inspection. By linking 1997-2003 Chicago elevated blood lead surveillance, environmental inspection, and building footprint data, we found that 49,362 children younger than 6 years with elevated BLLs lived at 30,742 buildings. Of those, 67 were "high-risk" buildings and these were associated with 994 children with elevated BLLs. On average, 15 children with elevated BLLs had lived in each building (range: 10-53, median: 13). Almost two thirds (n = 43) of the high-risk buildings had two or more referrals for inspection to the same apartment or housing unit; of those, 40 percent (n = 17) failed to maintain lead-safe status after compliance. Linking blood lead surveillance, environmental inspection, and building footprint databases allowed us to identify individual high-risk buildings. This approach prioritizes lead hazard control efforts and may help health, housing, and environmental agencies in targeting limited resources to increase lead-safe housing for children.

Measles immunization coverage determined by serology and immunization record from children in two Chicago communities.

OBJECTIVES: We compared the prevalence of measles immunization determined by serology with the prevalence of measles immunization determined by immunization records, and identified factors predictive of measles immunization among a sample of children from two Chicago communities. METHODS: We collected demographic information and blood specimens from a sample of children aged 12-71 months in two Chicago communities at risk for low measles immunization coverage levels. We collected immunization information from provider records, parent-held records, and the statewide immunization registry. We compared evidence of immunization determined by serology with evidence of immunization from these three sources of immunization records. RESULTS: The sample of children from the two communities had serologic measles immunity levels of 85% and 90%. Significantly fewer children had evidence of immunization by record in both communities (45% and 63%, respectively). CONCLUSIONS: Immunization coverage levels determined using immunization records were significantly lower than immunization coverage determined using serology. A fully populated immunization registry used by all immunization providers could prevent the problems of record loss and scatter.

High-intensity targeted screening for elevated blood lead levels among children in 2 inner-city Chicago communities.

OBJECTIVES: We assessed the prevalence of elevated blood lead levels (> or = 10 micrograms of lead per deciliter of blood), risk factors, and previous blood lead testing among children in 2 high-risk Chicago, Ill, communities. METHODS: Through high-intensity targeted screening, blood lead levels were tested and risks were assessed among a representative sample of children aged 1 to 5 years who were at risk for lead exposure. RESULTS: Of the 539 children who were tested, 27% had elevated blood lead levels, and 61% had never been tested previously. Elevated blood lead levels were associated with chipped exterior house paint. CONCLUSIONS: Most of the children who lived in these communities--where the prevalence for elevated blood lead levels among children was 12 times higher than the national prevalence--were not tested for lead poisoning. Our findings highlight the need for targeted community outreach that includes testing blood lead levels in accordance with the American Academy of Pediatrics' recommendations.