Felicia A. Rabito

Housing Interventions and Control of Asthma-Related Indoor Biologic Agents: A Review of the Evidence

Subject matter experts systematically reviewed evidence on the effectiveness of housing interventions that affect health outcomes, primarily asthma, associated with exposure to moisture, mold, and allergens. Three of the 11 interventions reviewed had sufficient evidence for implementation: multifaceted, in-home, tailored interventions for reducing asthma morbidity; integrated pest management to reduce cockroach allergen; and combined elimination of moisture intrusion and leaks and removal of moldy items to reduce mold and respiratory symptoms. Four interventions needed more field evaluation, 1 needed formative research, and 3 either had no evidence of effectiveness or were ineffective. The 3 interventions with sufficient evidence all applied multiple, integrated strategies. This evidence review shows that selected interventions that improve housing conditions will reduce morbidity from asthma and respiratory allergies.

Mold and Endotoxin Levels in the Aftermath of Hurricane Katrina: A Pilot Project of Homes in New Orleans Undergoing Renovation

Background After Hurricane Katrina, many New Orleans homes remained flooded for weeks, promoting heavy microbial growth. Objectives A small demonstration project was conducted November 2005–January 2006 aiming to recommend safe remediation techniques and safe levels of worker protection, and to characterize airborne mold and endotoxin throughout cleanup. Methods Three houses with floodwater lines between 0.3 and 2 m underwent intervention, including disposal of damaged furnishings and drywall, cleaning surfaces, drying remaining structure, and treatment with a biostatic agent. We measured indoor and outdoor bioaerosols before, during, and after intervention. Samples were analyzed for fungi [culture, spore analysis, polymerase chain reaction (PCR)] and endotoxin. In one house, real-time particle counts were also assessed, and respirator-efficiency testing was performed to establish workplace protection factors (WPF). Results At baseline, culturable mold ranged from 22,000 to 515,000 colony-forming units/m3, spore counts ranged from 82,000 to 630,000 spores/m3, and endotoxin ranged from 17 to 139 endotoxin units/m3. Culture, spore analysis, and PCR indicated that Penicillium, Aspergillus, and Paecilomyces predominated. After intervention, levels of mold and endotoxin were generally lower (sometimes, orders of magnitude). The average WPF against fungal spores for elastomeric respirators was higher than for the N-95 respirators. Conclusions During baseline and intervention, mold and endotoxin levels were similar to those found in agricultural environments. We strongly recommend that those entering, cleaning, and repairing flood-damaged homes wear respirators at least as protective as elastomeric respirators. Recommendations based on this demonstration will benefit those involved in the current cleanup activities and will inform efforts to respond to future disasters.

Cockroach exposure independent of sensitization status and association with hospitalizations for asthma in inner-city children

BACKGROUND Children with asthma living in urban environments experience disproportionately high asthma hospitalization rates. Excessive exposure to perennial allergens, including cockroach and house dust mite (HDM), have been implicated, but data are limited. OBJECTIVE To examine the relation between cockroach and HDM exposure and measures of asthma morbidity and health care utilization. METHODS Participants included 86 atopic asthmatic children living in New Orleans, Louisiana. Sensitization status was determined by means of serum specific IgE testing, and vacuum dust samples were collected for allergen analysis. Logistic regression analysis was used to assess the odds of persistent wheezing, emergency department visits, and asthma hospitalization in those with high vs low levels of allergen exposure. RESULTS Approximately 44% and 40% of children were exposed to Bla g 1 levels greater than 2 U/g and HDM levels greater than 2 μg/g, respectively, and 24% reported at least 1 hospitalization in the previous 4 months. The median Bla g 1 level was significantly higher in the homes of children hospitalized compared with those with no hospital admissions (7.2 vs 0.8 U/g). In multivariable models, the odds of hospitalization were significantly higher in children exposed to Bla g 1 levels greater than 2 U/g (adjusted odds ratio, 4.2; 95% confidence interval, 1.24-14.17), independent of sensitization status. Exposure to HDMs was not associated with any measure of morbidity. CONCLUSIONS Exposure to cockroach allergen was strongly associated with increased hospitalization in children with asthma. This effect cannot be explained entirely by IgE-mediated inflammation. Controlled interventional trials are needed to determine whether isolated cockroach abatement improves asthma control.

Estimated burden of blood lead levels ⩾5μg/dl in 1999–2002 and declines from 1988 to 1994

In light of recent data suggesting adverse health effects at blood lead levels (PbB) <10 microg/dl, lowering the current definition of elevated blood lead (>or=10 microg/dl) has been recommended. To ascertain the population level impact of such a change, we calculated the prevalence of PbB >or=5 microg/dl in 1-21-year-old population in the United States. Furthermore, we characterized changes in PbB between 1988-1994 and 1999-2002. We analyzed data from the National Health and Nutrition Examination Survey (NHANES) III (n=10,755) and NHANES 1999-2002 (n=8013). In 1999-2002, about 91.7% of study children had detectable levels of lead in the blood. Among them, 7.3%, 2.8%, and 1.0% children and adolescents aged 1-5, 6-11, and 12-21 years, respectively, had PbB between 5 and 9.9 microg/dl. This number translates to approximately 2.4 million individuals. Between 1988-1994 and 1999-2002, the geometric mean PbB declined from 2.88 to 1.94 microg/dl in children 1-5 years, 1.80 to 1.36 microg/dl in children 6-11 years, and 1.24-1.02 microg/dl in children and adolescents 12-21 years of age. Also, the prevalence of PbB >or=5 microg/dl declined from 25.7% to 8.8%, 12.8% to 3.0%, and 7.5% to 1.2% in these age groups, respectively.A substantial proportion of children may be at risk for adverse health effects from lead exposure below 10 microg/dl and a large number of children will be classified as having elevated PbB if 5 microg/dl is considered the threshold. Significant public health resources will have to be mobilized for intervention, screening, and case management of these children.

Individual, Housing, and Neighborhood Correlates of Asthma among Young Urban Children

Using data from a large cohort of urban children, this study identified multilevel correlates of asthma to determine whether neighborhood attributes remain associated with asthma after adjustment for individual level and immediate housing characteristics. A cross-sectional analysis was conducted using data from the Fragile Families and Child Well-being Study and its substudy, the In-Home Longitudinal Study of Pre-Schooled Age Children (n = 1,784). The primary outcome was asthma diagnosis by age 5. Sociodemographic measures were assessed via telephone survey, housing and block conditions recorded via direct observation, and neighborhood characteristics came from geocoded census tract data. After multivariable adjustment, non-Hispanic Black, Puerto Rican, or other Hispanic race, child’s lack of insurance coverage, male gender, presence of allergies, the exterior condition of a child’s home, mother’s educational attainment, and the percent of the neighborhood population with a bachelor’s degree remained significantly associated with having received an asthma diagnosis by age 5. The authors identified sociodemographic and economic factors at the individual, household, and neighborhood level which are correlates of childhood asthma in urban areas. After adjustment for more proximal characteristics, the effects of all neighborhood markers were minimal, with the exception of neighborhood education.

Urinary triclosan concentrations are inversely associated with body mass index and waist circumference in the US general population: Experience in NHANES 2003–2010

BACKGROUND Humans are extensively exposed to triclosan, an antibacterial and antifungal agent. Triclosans effects on human health, however, have not been carefully investigated. OBJECTIVE To examine whether triclosan exposure is associated with obesity traits. METHODS This study included 2898 children (6-19 years old) and 5066 adults (20 years or older) who participated in the National Health and Nutrition Examination Surveys (NHANES) 2003-2010 and had a detectable level of urinary triclosan. Multiple linear regression models were used to examine the association between urinary triclosan and both body mass index (BMI) and waist circumference. RESULTS Each standard deviation increase in urinary triclosan was associated with a 0.34 (95% confidence interval, CI: 0.05, 0.64) kg/m² lower level of BMI (P=0.02) and 0.92 (95% CI: 0.09, 1.74)cm smaller waist circumference (P=0.03) in boys, and a 0.62 (95% CI: 0.31, 0.94) kg/m² lower level of BMI (P=0.0002) and 1.32 (95% CI: 0.54, 2.09) cm smaller waist circumference in girls (P=0.001); a 0.42 (95% CI: 0.06, 0.77) kg/m² lower level of BMI (P=0.02) and 1.35 (95% CI: 0.48, 2.22) cm smaller waist circumference (P=0.003) in men, and a 0.71 (95% CI: 0.34, 1.07) kg/m² lower level of BMI (P=0.0002) and 1.68 (95% CI: 0.86, 2.50) cm smaller waist circumference (P=0.0001) in women. In both children and adults, there was a consistent trend for lower levels of BMI and smaller waist circumference with increasing levels of urinary triclosan, from the lowest to the highest quartile of urinary triclosan (P ≤ 0.001 in all cases). CONCLUSION Triclosan exposure is inversely associated with BMI and waist circumference. The biological mechanisms linking triclosan exposure to obesity await further investigation.

A single intervention for cockroach control reduces cockroach exposure and asthma morbidity in children

Background Exposure to cockroaches is an important asthma trigger, particularly for children with asthma living in inner cities. Integrated pest management is the recommended approach to cockroach abatement; however, it is costly and difficult to implement. The impact of reducing cockroach exposure on asthma outcomes is not known. Objective We sought to test the use of a single intervention, insecticidal bait, to reduce cockroach exposure in the home of children with asthma in New Orleans and to examine the impact of cockroach reduction on asthma outcomes. Methods One hundred two children aged 5 to 17 years with moderate to severe asthma were enrolled in a 12‐month randomized controlled trial testing the use of insecticidal bait on cockroach counts and asthma morbidity. Homes were visited 6 times and asthma symptoms were assessed every 2 months. Results After adjustment, intervention homes had significantly fewer cockroaches than did control homes (mean change in cockroaches trapped, 13.14; 95% CI, 6.88‐19.39; P < .01). Children in control homes had more asthma symptoms and unscheduled health care utilization in the previous 2 weeks (1.82, 95% CI, 0.14‐3.50, P = .03; 1.17, 95% CI, 0.11‐2.24, P = .03, respectively) and a higher proportion of children with FEV1 of less than 80% predicted (odds ratio, 5.74; 95% CI, 1.60‐20.57; P = .01) compared with children living in intervention homes. Conclusions Previous research has demonstrated improvement in asthma health outcomes using multifaceted interventions. The strategic placement of insecticidal bait, which is inexpensive, has low toxicity, and is widely available, resulted in sustained cockroach elimination over 12 months and was associated with improved asthma outcomes. This single intervention may be an alternative to multifaceted interventions currently recommended to improve asthma morbidity.

Environmental Lead after Hurricane Katrina: Implications for Future Populations

Background: As a result of Hurricane Katrina, > 100,000 homes were destroyed or damaged and a significant amount of sediment was deposited throughout the city of New Orleans, Louisiana. Researchers have identified the potential for increased lead hazards from environmental lead contamination of soils. Objectives: We assessed the distribution of residential soil and dust lead 2 years poststorm and compared soil lead before and after the storm. Methods: We conducted a cross-sectional study in New Orleans in which households were selected by stratified random sampling. A standard residential questionnaire was administered, and lead testing was performed for both the interior and exterior of homes. Logistic regression was used to identify significant predictors of interior and exterior lead levels in excess of allowable levels. Results: One hundred nine households were enrolled; 61% had at least one lead measurement above federal standards. Of homes with bare soil, 47% had elevated lead and 27% had levels exceeding 1,200 ppm. Housing age was associated with soil lead, and housing age and soil lead were associated with interior lead. Race, income, and ownership status were not significantly associated with either interior or exterior lead levels. The median soil lead level of 560 ppm was significantly higher than the median level of samples collected before Hurricane Katrina. Conclusions: The high prevalence (61%) of lead above recommended levels in soil and dust samples in and around residences raises concern about potential health risks to the New Orleans population, most notably children. Steps should be taken to mitigate the risk of exposure to lead-contaminated soil and dust. Further research is needed to quantify the possible contribution of reconstruction activities to environmental lead levels.

Children's respiratory health and mold levels in New Orleans after Katrina: A preliminary look

BACKGROUND When the federal levee system broke after Hurricane Katrina, 80 percent of New Orleans, approximately 134,000 homes, flooded. As repopulation and revitalization activities continue, exposure to mold and other respiratory irritants has emerged as a major health concern; however, there has been no study examining childrens respiratory health and indoor mold levels in the post-Katrina environment. OBJECTIVE The Childrens Respiratory Health Study was designed as a preliminary examination of indoor air levels of mold, childrens lung function, and common indices of respiratory health in a select sample of children returning to live in New Orleans immediately after Hurricane Katrina. METHODS Children were recruited from a private primary school in the Garden District of New Orleans. Respiratory health questionnaire and spirometric data were collected on children 7 to 14 years of age, and mold air sampling was conducted at baseline and again after 2 months. CONCLUSIONS There was an overall decrease in mold levels and respiratory symptoms over the study period, and indoor mold levels were low despite reported hurricane damage.

The Relationship Between a Specific IgE Level and Asthma Outcomes: Results from the 2005-2006 National Health and Nutrition Examination Survey

BACKGROUND Allergen exposure is associated with increased specific IgE (sIgE), and allergen exposure plus sensitization is predictive of asthma outcomes. However, it is not known if sIgE is predictive of asthma outcomes in the absence of exposure data. OBJECTIVE To investigate whether IgE to indoor allergens is predictive of and has a dose-response relationship with asthma emergency department (ED) visits and wheeze. METHODS In the 2005-2006 National Health and Nutrition Examination Survey, 351 children and 390 adults reported current asthma. Continuous sIgE to 9 indoor allergens were considered. Asthma morbidity in the past year was measured by wheezing. Health care utilization was defined as any asthma ED visits in the past year. RESULTS Analyses were adjusted for race, age, education, poverty index ratio and (in adults) tobacco use. In children, ED visits were associated with cockroach (odds ratio [OR] 1.5 [95% CI, 1.1-2 .1), rat (OR 1.9 [95% CI, 1.2-2.8]), and Aspergillus (OR 1.6 [95% CI, 1.001-2.60]). Continuous Aspergillus (OR 1.5 [95% CI, 1.04-2.1), Alternaria (OR 1.4 [95% CI, 1.1-1.6]), and total IgE (OR 1.2 [95% CI, 1.1-1.4]) were associated with wheeze in children. Adult ED visits were associated with sIgE for dust mites (Dermatophagoides pteronyssinus OR 1.6 [95% CI, 1.3-2.1]; Dermatophagoides farinae OR 1.6 [95% CI, 1.3-1.9]), total IgE (OR 1.4 [95% CI, 1.04- 1.9]), and the sum of sIgEs (OR 1.6 [95% CI, 1.2-2.2]). CONCLUSIONS Sensitization to particular indoor environmental allergens was found to be a risk factor for wheeze and asthma ED visits. These outcomes increased as the concentration of sIgE to these allergens increased.