A multi-city study of indoor air quality in green vs non-green low-income housing

OBJECTIVES

The condition of the home is a strong predictor of exposure to environmental contaminants, with low-income households being particularly vulnerable. Therefore, improving housing standards is a priority. Housing built to "green" standards, with improved building methods and materials, has been suggested to reduce contaminants. However, evidence is limited as to which contaminants are reduced. The Green Housing Study was conducted to address this issue. The study hypothesis was that housing built using green components has lower concentrations of environmental contaminants compared to conventional housing.

METHODS

A repeated-measures, 12-month cohort study was performed in three U.S. cities. Data were collected in the home at three time points throughout a year. The level of contaminants were estimated using air samples for particulate matter and black carbon, dust samples for aeroallergens and pesticides, and resident or study staff reporting evidence of mold. To investigate source(s) of PM2.5 and black carbon, multivariable models using stepwise variable selection were developed.

RESULTS

In adjusted generalized estimating equations (GEE) models, black carbon concentration (μg/m3) (β = -0.22, 95% CI = -0.38 to -0.06, p = 0.01), permethrin (OR = 0.28, 95% CI = 0.15-0.49, p < 0.0001), and reported mold (OR = 0.29, 95% CI = 0.13-0.68, p = 0.003) were significantly lower in green homes. Cockroach antigen was also lower in green homes (OR = 0.59, 95% CI = 0.33-1.08, p = 0.09), although not statistically significant. We found that 68% of PM2.5 was explained by dwelling type and smoking and 42% of black carbon was explained by venting while cooking and use of a gas stove.

CONCLUSIONS

This study provides quantitative data suggesting benefits of incorporating green building practices on the level of numerous environmental contaminants known to be associated with health. Occupant behavior, particularly smoking, is an important contributor to indoor air pollution.

Pesticide exposure and asthma morbidity in children residing in urban, multi-family housing

BACKGROUND

Children are potentially more susceptible to the adverse effects of pesticides due to more sensitive organ systems and lower capacity to metabolize and eliminate chemicals compared to adults. The health risks are particularly concerning children with asthma, living in low-income neighborhoods in multi-family housing because of their impaired respiratory health, and factors associated with low-income, multi-family environments.

OBJECTIVE

To assess the association between pesticide exposure and asthma morbidity among children 7-12 years residing in low-income, multi-family housing.

METHODS

The concentrations of seven urinary pesticide biomarkers: 3,5,6-trichloro-2-pyridinol (TCPy), 2-isopropyl-4-methyl-6-hydroxypyrimidine, para-nitrophenol (PNP), 3-phenoxybenzoic acid (3-PBA), 4-fluoro-3-phenoxybenzoic acid, trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane-1-carboxylic acid, and 2,4-dichlorophenoxyacetic acid (2,4-D) were measured. Children (n = 162) were followed for one year with three measures of pesticides biomarkers. Associations between individual biomarkers and asthma attack, asthma related health care utilization, and fraction of exhaled nitric oxide (FeNO), adjusting for demographic and household factors were examined with Generalized Estimating Equations (GEE). Weighted Quantile Sum (WQS) regression was used to examine the effect of pesticide mixture on asthma attacks and asthma-related health care utilization (HCU).

RESULTS

In adjusted GEE models, positive non-significant associations were found between PNP and HCU (adjusted Odds Ratio(aOR):2.05 95% CI:0.76-5.52) and null associations for 3-PBA and HCU (aOR:1.07 95% CI: 0.88-1.29). Higher concentrations of PNP and 2,4-D were associated with significantly lower FeNO levels (PNP: -17.4%; 2,4-D:-19.74%). The mixture was positively associated with HCU in unadjusted (OR: 1.56 97.5% CI: 1.08-2.27) but not significant in adjusted models (aOR: 1.40 97.5% CI: .86-2.29). The non-specific pyrethroid biomarker 3-PBA at baseline contributed the greatest weight to the index (45%).

SIGNIFICANCE

There were non-significant associations between pesticide biomarkers and respiratory outcomes in children with asthma. There was a suggestive association between urinary pesticide biomarkers and HCU. Further studies with larger sample sizes could help to confirm these findings.

IMPACT STATEMENT

Pesticide exposure among children in the urban environment is ubiquitous and there is a dearth of information on the impact of low-level chronic exposure in vulnerable populations. This study suggested that pesticide exposure at concentrations below the national average may not affect asthma morbidity in children. However, different biomarkers of pesticides showed different effects, but the mixture suggested increasing pesticide exposure results in asthma related HCU. The results may show that children with asthma may be at risk for negative health outcomes due to pesticides and the need to further examine this relationship.

Associations of Emergency Department Visits for Asthma with Precipitation and Temperature on Thunderstorm Days: A Time-Series Analysis of Data from Louisiana, USA, 2010-2012

BACKGROUND

Studies of thunderstorm asthma to understand risk factors using high-resolution climate data and asthma outcomes on a large scale are scarce. Moreover, thunderstorm asthma is not well studied in the United States.

OBJECTIVES

We examined whether climate parameters involved in thunderstorms are associated with emergency department (ED) visits for acute asthma attacks in the United States.

METHODS

We analyzed 63,789 asthma-related, daily ED visits for all age groups, and thunderstorm-associated climate data in Louisiana during 2010 through 2012. We performed time-series analyses using quasi-Poisson regression models with natural cubic splines of date, parish, holiday, day of week, season, daily maximum concentrations of ozone (O3) and fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)], and daily mean pressure, precipitation, and temperature. Because of a significant interaction effect between temperature and lightning days on asthma-related visits, we performed stratified analyses by days with/without lightning or thunderstorm (defined by any lightning and precipitation).

RESULTS

On thunderstorm days, higher asthma-related ED visits were associated with higher daily mean precipitation [relative risk (RR)=1.145 per 1 g/m2/s (95% CI: 1.009, 1.300)] and lower daily mean temperature [RR=1.011 per 1°C change (1.000-1.021)] without carry-over effect to the next non-thunderstorm day. These higher risks were found mainly among children and adults <65 years of age. We observed similar results on lightning days. However, we did not find similar associations for non-thunderstorm or non-lightning days. Daily maximum O3 and PM2.5 levels were not significantly associated with asthma ED visits on thunderstorm days.

DISCUSSION

Higher precipitation and lower temperature on thunderstorm days appear to contribute to asthma attacks among people with asthma, suggesting they should consider taking precautions during thunderstorms. EDs should consider preparing for a potential increase of asthma-related visits and ensuring sufficient stock of emergency medication and supplies for forecasted severe thunderstorm days. https://doi.org/10.1289/EHP10440.

Side-by-side comparison of parent vs. technician-collected respiratory swabs in low-income, multilingual, urban communities in the United States

Background

Home-based swabbing has not been widely used. The objective of this analysis was to compare respiratory swabs collected by mothers of 7–12-year-olds living in low-income, multilingual communities in the United States with technician collected swabs.

Methods

Retrospective data analysis of respiratory samples collected at home by mothers compared to technicians. Anterior nasal and throat specimens collected using flocked swabs were combined in dry tubes. Test was done using TaqMan array cards for viral and bacterial pathogens. Cycle threshold (Ct) values of ribonuclease P (RNP) gene were used to assess specimen quality. Ct < 40 was interpreted as a positive result. Concordance of pathogen yield from mother versus technician collected swabs were analyzed using Cohen’s Kappa coefficients. Correlation analysis, paired t-test, and Wilcoxon signed-rank test for paired samples were used for RNP Ct values.

Results

We enrolled 36 households in Cincinnati (African American) and 44 (predominately Chinese or Latino) in Boston. In Cincinnati, eight of 32 (25%) mothers did not finish high school, and 11 (34%) had finished high school only. In Boston, 13 of 44 (30%) mothers had less than a high school diploma, 23 (52%) had finished high school only. Mother versus technician paired swabs (n = 62) had similar pathogen yield (paired t-test and Wilcoxon signed rank test p-values = 0.62 and 0.63, respectively; 95% confidence interval of the difference between the two measurements = − 0.45–0.75). Median Ct value for RNP was 22.6 (interquartile range, IQR = 2.04) for mother-collected and 22.4 (IQR = 2.39) for technician-collected swabs (p = 0.62). Agreement on pathogen yield between samples collected by mothers vs. technicians was higher for viruses than for bacterial pathogens, with high concordance for rhinovirus/enterovirus, human metapneumovirus, and adenovirus (Cohen’s kappa coefficients ≥80%, p < 0.0001). For bacterial pathogens, concordance was lower to moderate, except for Chlamydia pneumoniae, for which kappa coefficient indicated perfect agreement.

Conclusion

Mothers with a range of education levels from low-income communities were able to swab their children equally well as technicians. Home-swabbing using dry tubes, and less invasive collection procedures, could enhance respiratory disease surveillance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-12523-3.

Pyrethroid exposure among children residing in green versus non-green multi-family, low-income housing

BACKGROUND

There is growing concern about children's chronic low-level pesticide exposure and its impact on health. Green building practices (e.g., reducing leakage of the thermal and pressure barrier that surrounds the structure, integrated pest management, improved ventilation) have the potential to reduce pesticide exposure. However, the potential impact of living in green housing on children's pesticide exposure is unknown.

OBJECTIVE

To address this question, a longitudinal study of pyrethroid metabolites (3-phenoxybenzoic acid [3-PBA], 4-fluoro-3-phenoxybenzoic acid [4-F-3-PBA], trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid [trans-DCCA]) in first morning void urine, collected from 68 children from New Orleans, Louisiana residing in green and non-green housing was conducted.

METHODS

Children were followed for 1 year with three repeated measures of pesticide exposure. Generalized estimating equations examined associations between housing type (green vs. non-green) and urinary pyrethroid metabolite concentrations adjusting for demographic and household factors over the year.

RESULTS

Ninety-five percent of samples had detectable concentrations of 3-PBA (limit of detection [LOD]: 0.1 μg/L); 8% of 4-F-3-PBA (LOD: 0.1 μg/L), and 12% of trans-DCCA (LOD: 0.6 μg/L). In adjusted models, green housing was not associated with statistically significant differences in children's 3-PBA urinary concentrations compared to non-green housing.

Mold clean-up practices vary by sociodemographic and allergy factors

We examined mold clean-up practices in a general population (not selected on history of natural disaster). We used a population-based survey (n= 3,624) to assess associations between sociodemographic/ housing/ respiratory health variables and mold clean-up, PPE use, and cleaning agent use. Bleach was the most commonly used cleaning agent with approximately 90% of residents reporting using bleach alone or with other agents. More respondents used gloves (76%) than any other PPE. The use of PPE varied; 42% of bleach users wore a breathing mask/respirator compared with only 19% of soap and water users. Hispanic populations frequently reported mold clean-up. Bleach use was less likely in the West and among Asians. Although "Green" products were rarely used, Asians were more likely to use them. Bleach was the most commonly used cleaning agent for mold, and PPE use was common when using bleach, supporting the need for current CDC safe use recommendations.

Endotoxin, food allergen sensitization, and food allergy: A complementary epidemiologic and experimental study

BACKGROUND

Household endotoxin levels have been variably associated with risk for asthma and atopy.

METHODS

We studied participants from the 2005-2006 National Health and Nutrition Examination Survey (NHANES, n = 6963), a large cohort representative of the US population (aged 1-84 years). We built logistic regression models to test for associations between house dust endotoxin and sensitization to specific foods (milk, egg, and peanut). To experimentally explore the detected epidemiologic associations, peripheral blood mononuclear cells (PBMCs) were collected from 21 children (aged 1-19 years) mono-food allergic (ie, sensitized and clinically reactive) to milk, egg, or peanut and nonallergic controls for stimulation with endotoxin and secreted cytokine measurement. For each food allergy, linear mixed-effects models were built to test the association between endotoxin stimulation and cytokine level.

RESULTS

Among NHANES subjects, the geometric mean household endotoxin level was 15.5 EU/mg (GSE 0.5). Prevalence of food allergen sensitization (sIgE ≥ 0.35 kU_A /L) varied by food: milk 5.7%, egg 4.0%, and peanut 7.9%. In models adjusted for potential confounders (age, race, country of birth, total people per household, US region, and history of wheezing in the past year), household endotoxin level was associated with sensitization to milk (OR 1.7, 95% CI 1.2-2.1) and egg (OR 1.4, 95% CI 1.01-1.9), but not peanut (OR 0.98, 95% CI 0.8-1.2). Interferon-γ levels of endotoxin-stimulated PBMCs from children allergic to milk or egg, but not peanut, were significantly lower compared to controls in linear mixed-effects models adjusted for repeated measures, experimental variables, age, and inter-individual variability (P-values .007, .018, and .058, respectively).

CONCLUSION

Higher household endotoxin is associated with increased odds of milk and egg sensitization. Altered cytokine responsiveness to endotoxin is also observed in PBMCs from individuals with milk and egg allergy.

Assessing Indoor Environmental Control Practices by Race/Ethnicity Among Children With Asthma in 14 US States and Puerto Rico, 2013-2014

INTRODUCTION

In the United States, children in Puerto Rico and non-Hispanic black children in the mainland US have a higher burden of asthma than non-Hispanic white children in the mainland US. We examined indoor environmental control (IEC) practices that reduce asthma triggers, by race/ethnicity among children in the mainland US and Puerto Rico.

METHODS

We used 2013 and 2014 data from the Behavioral Risk Factor Surveillance System Asthma Call-back Survey Child Questionnaire from 14 states and Puerto Rico to measure the association between race/ethnicity and IEC practices, adjusting for sociodemographic covariates, among children identified as ever receiving an asthma diagnosis. Racial/ethnic groups were compared in 14 US states using aggregated data. Separate analyses compared IEC practices for children diagnosed with asthma in Puerto Rico with children of all races/ethnicities diagnosed with asthma in 14 states.

RESULTS

Among households in 14 US states that had a child with asthma, non-Hispanic black children were more likely than non-Hispanic white children to use an air purifier (36.8% vs 25.2%; adjusted odds ratio [aOR] = 2.0; 95% confidence interval [CI], 1.3-3.2) and avoid pets in the bedroom (87.9% vs 58.3%; aOR = 4.5; 95% CI, 2.3-8.8). Children in Puerto Rico were more likely than children in 14 states to use dust mite-impermeable pillow covers (53.7% vs 36.4%; aOR = 3.6; 95% CI, 1.8-7.1) and mattress encasements (60.3% vs 30.3%; aOR = 2.4; 95% CI, 1.2-4.8).

CONCLUSION

IEC practices such as using air purifiers, pillow covers, mattress encasements, and avoiding pets in the bedroom vary by race/ethnicity among children with asthma. These findings show that vulnerable populations are using IEC practices, but asthma prevention and control measures should continue to be assessed.

Hurricane-Associated Mold Exposures Among Patients at Risk for Invasive Mold Infections After Hurricane Harvey - Houston, Texas, 2017

In August 2017, Hurricane Harvey caused unprecedented flooding and devastation to the Houston metropolitan area (1). Mold exposure was a serious concern because investigations after Hurricanes Katrina and Rita (2005) had documented extensive mold growth in flood-damaged homes (2,3). Because mold exposure can cause serious illnesses known as invasive mold infections (4,5), and immunosuppressed persons are at high risk for these infections (6,7), several federal agencies recommend that immunosuppressed persons avoid mold-contaminated sites (8,9). To assess the extent of exposure to mold and flood-damaged areas among persons at high risk for invasive mold infections after Hurricane Harvey, CDC and Texas health officials conducted a survey among 103 immunosuppressed residents in Houston. Approximately half of the participants (50) engaged in cleanup of mold and water-damaged areas; these activities included heavy cleanup (23), such as removing furniture or removing drywall, or light cleanup (27), such as wiping down walls or retrieving personal items. Among immunosuppressed persons who performed heavy cleanup, 43% reported wearing a respirator, as did 8% who performed light cleanup. One participant reported wearing all personal protective equipment (PPE) recommended for otherwise healthy persons (i.e., respirator, boots, goggles, and gloves). Immunosuppressed residents who are at high risk for invasive mold infections were exposed to mold and flood-damaged areas after Hurricane Harvey; recommendations from health care providers to avoid exposure to mold and flood-damaged areas could mitigate the risk to immunosuppressed persons.

Complex relationships between vitamin D and allergic sensitization among Puerto Rican 2-year-old children

BACKGROUND

In the United States, Puerto Ricans have a higher prevalence of asthma than other Latino ethnicities. Low vitamin D levels for children living in northern climates could be a factor.

OBJECTIVE

To assess serum 25-hydroxyvitamin D [25(OH)D] distributions (a marker of vitamin D) and associations among vitamin D, allergic sensitization, early wheeze, and home/demographic factors.

METHODS

Puerto Rican infants born in New York City, with a maternal history of atopy, were enrolled in a birth cohort. Blood was collected at age 2 years (n = 154; 82 males and 72 females). Serum 25(OH)D and immunoglobulin E (IgE) (indoor allergen-specific and total) were determined using immunoassays. Home/demographic characteristics and respiratory symptoms were assessed by questionnaire.

RESULTS

The median concentration of 25(OH)D was 22.6 ng/mL; 32% were at risk of deficiency or inadequacy (<12 or 12-19 ng/mL). Serum 25(OH)D levels were lower in the heating (a surrogate for less sun exposure in colder months) compared with nonheating (26.1 vs 22.7 ng/mL, P = .02) season, but were not associated with allergen-specific IgE levels or with level of acculturation (measured by maternal birthplace). However, low 25(OH)D levels (below median) were associated with high total IgE >100 IU/mL (P = .01). Also, 25(OH)D concentrations differed between children who attended daycare and those who did not (21.8 vs 24.5 ng/mL; t test, P = .02). Serum 25(OH)D was not associated with wheeze or asthma by 2 years of age (P = .43).

CONCLUSION

Vitamin D deficiency, possibly linked with allergic pathways, may partially explain the trajectory for disproportionate asthma burden among Puerto Ricans, especially those born and raised in colder climates.

Variability of indoor fungal microbiome of green and non-green low-income homes in Cincinnati, Ohio

"Green" housing is designed to use low-impact materials, increase energy efficiency and improve occupant health. However, little is known about the indoor mycobiome of green homes. The current study is a subset of a multicenter study that aims to investigate the indoor environment of green homes and the respiratory health of asthmatic children. In the current study, the mycobiome in air, bed dust and floor dust was compared between green (study site) and non-green (control site), low-income homes in Cincinnati, Ohio. The samples were collected at baseline (within four months following renovation), and 12months after the baseline at the study site. Parallel sample collection was conducted in non-green control homes. Air samples were collected by PM2.5 samplers over 5-days. Bed and floor dust samples were vacuumed after the air sampling was completed. The DNA sample extracts were analyzed using ITS amplicon sequencing. Analysis indicated that there was no clear trend in the fungal communities between green and non-green homes. Instead, fungal community differences were greatest between sample types - air, bed, and floor. Microbial communities also changed substantially between sampling intervals in both green and non-green homes for all sample types, potentially indicating that there was very little stability in the mycobiomes. Research gaps remain regarding how indoor mycobiome fluctuates over time. Longer follow-up periods might elucidate the effect of green renovation on microbial load in buildings.

NIAID, NIEHS, NHLBI, and MCAN Workshop Report: The indoor environment and childhood asthma-implications for home environmental intervention in asthma prevention and management

Environmental exposures have been recognized as critical in the initiation and exacerbation of asthma, one of the most common chronic childhood diseases. The National Institute of Allergy and Infectious Diseases; National Institute of Environmental Health Sciences; National Heart, Lung, and Blood Institute; and Merck Childhood Asthma Network sponsored a joint workshop to discuss the current state of science with respect to the indoor environment and its effects on the development and morbidity of childhood asthma. The workshop included US and international experts with backgrounds in allergy/allergens, immunology, asthma, environmental health, environmental exposures and pollutants, epidemiology, public health, and bioinformatics. Workshop participants provided new insights into the biologic properties of indoor exposures, indoor exposure assessment, and exposure reduction techniques. This informed a primary focus of the workshop: to critically review trials and research relevant to the prevention or control of asthma through environmental intervention. The participants identified important limitations and gaps in scientific methodologies and knowledge and proposed and prioritized areas for future research. The group reviewed socioeconomic and structural challenges to changing environmental exposure and offered recommendations for creative study design to overcome these challenges in trials to improve asthma management. The recommendations of this workshop can serve as guidance for future research in the study of the indoor environment and on environmental interventions as they pertain to the prevention and management of asthma and airway allergies.

Exposure science in an age of rapidly changing climate: challenges and opportunities

Climate change is anticipated to alter the production, use, release, and fate of environmental chemicals, likely leading to increased uncertainty in exposure and human health risk predictions. Exposure science provides a key connection between changes in climate and associated health outcomes. The theme of the 2015 Annual Meeting of the International Society of Exposure Science-Exposures in an Evolving Environment-brought this issue to the fore. By directing attention to questions that may affect society in profound ways, exposure scientists have an opportunity to conduct "consequential science"-doing science that matters, using our tools for the greater good and to answer key policy questions, and identifying causes leading to implementation of solutions. Understanding the implications of changing exposures on public health may be one of the most consequential areas of study in which exposure scientists could currently be engaged. In this paper, we use a series of case studies to identify exposure data gaps and research paths that will enable us to capture the information necessary for understanding climate change-related human exposures and consequent health impacts. We hope that paper will focus attention on under-developed areas of exposure science that will likely have broad implications for public health.

Indoor air quality in green-renovated vs. non-green low-income homes of children living in a temperate region of US (Ohio)

Green eco-friendly housing includes approaches to reduce indoor air pollutant sources and to increase energy efficiency. Although sealing/tightening buildings can save energy and reduce the penetration of outdoor pollutants, an adverse outcome can be increased buildup of pollutants with indoor sources. The objective of this study was to determine the differences in the indoor air quality (IAQ) between green and non-green homes in low-income housing complexes. In one housing complex, apartments were renovated using green principles (n=28). Home visits were conducted immediately after the renovation, and subsequently at 6 months and at 12 months following the renovation. Of these homes, eight homes had pre-renovation home visits; this allowed pre- and post-renovation comparisons within the same homes. Parallel visits were conducted in non-green (control) apartments (n=14) in a nearby low-income housing complex. The IAQ assessments included PM2.5, black carbon, ultrafine particles, sulfur, total volatile organic compounds (VOCs), formaldehyde, and air exchange rate. Data were analyzed using linear mixed-effects models. None of the indoor pollutant concentrations were significantly different between green and non-green homes. However, we found differences when comparing the concentrations before and after renovation. Measured immediately after renovation, indoor black carbon concentrations were significantly lower averaging 682 ng/m(3) in post-renovation vs. 2364 ng/m(3) in pre-renovation home visits (p=0.01). In contrast, formaldehyde concentrations were significantly higher in post-renovated (0.03 ppm) than in pre-renovated homes (0.01 ppm) (p=0.004). Questionnaire data showed that opening of windows occurred less frequently in homes immediately post-renovation compared to pre-renovation; this factor likely affected the levels of indoor black carbon (from outdoor sources) and formaldehyde (from indoor sources) more than the renovation status itself. To reduce IAQ problems and potentially improve health, careful selection of indoor building materials and ensuring sufficient ventilation are important for green building designs.

Procedures to Assist Health Care Providers to Determine When Home Assessments for Potential Mold Exposure Are Warranted

Drawing evidence from epidemiology and exposure assessment studies and recommendations from expert practice, we describe a process to guide health care providers helping their patients who present with symptoms that might be associated with living in damp housing. We present the procedures in the form of a guided 2-part interview. The first part has 5 questions that triage the patient toward a more detailed questionnaire that reflects features of housing conditions known to be reliably associated with exposures to mold and dampness contaminants. We chose the questions based on the conditions associated with moisture problems in homes across the United States and Canada. The goal is to facilitate the clinician's effort to help patients reduce exposure to environmental triggers that elicit symptoms to better manage their disease.

Mold populations and dust mite allergen concentrations in house dust samples from across Puerto Rico

Lifetime childhood asthma prevalence (LCAP) percentages in Puerto Rico Health Regions (HR) are substantially higher in northeastern vs. southwestern HR. Higher average relative humidity in the northeast might promote mold and mite exposures and possibly asthma prevalence. To test this hypothesis, mold contamination, Environmental Relative Moldiness Index (ERMI) values were measured in floor dust (n = 26) and dust mite allergen concentrations in bed dust (n = 14). For this analysis, the eight HR were divided into those with LCAP > 30% (n = 3) and <  30% (n = 5). The average ERMI value was significantly greater (Wilcoxon Rank Sum, p < 0.001) in high than in low LCAP HR (14.5 vs. 9.3). The dust mite antigens Der p 1, Der f 1, and Blo t 5 were detected in 90% of bed samples, but the concentrations were not significantly different in high vs. low LCAP HR. Mold exposures might partially explain the differences in LCAP HR in Puerto Rico.

Asthma and allergy development: contrasting influences of yeasts and other fungal exposures

BACKGROUND

Infancy is a developmental stage with heightened susceptibility to environmental influences on the risk of chronic childhood disease. Few birth cohort studies have detailed measures of fungal diversity data in infants' bedrooms, limiting the potential to measure long-term associations of these complex exposures with development of asthma or allergy.

OBJECTIVE

We evaluated the relation of home fungal levels in infancy to repeated measures of wheeze and development of asthma and rhinitis by age 13, and sensitization by age 12 years.

METHODS

In the Epidemiology of Home Allergens and Asthma prospective birth cohort study, we recruited 408 children with family history of allergic disease or asthma. When children were aged 2-3 months, we measured culturable fungi in bedroom air and dust, and in outdoor air. Main outcomes included ascertainment of symptoms/disease onset by questionnaire from birth through age 13. We estimated hazard ratios and, for wheeze and sensitization, odds ratios for an interquartile increase in log-transformed fungal concentrations, adjusting for other outcome predictors and potential confounders.

RESULTS

Elevated levels of yeasts in bedroom floor dust were associated with reduced: i) wheeze at any age; ii) fungal sensitization; and iii) asthma development by age 13 (hazard ratio (HR) = 0.86; 95% confidence interval (CI), [0.75 to 0.98]). Outdoor airborne Cladosporium and dustborne Aspergillus predicted increased rhinitis. Risk of fungal sensitization by age 12, in response to environmental Alternaria and Aspergillus, was elevated in children with a maternal history of fungal sensitization.

CONCLUSIONS AND CLINICAL RELEVANCE

Despite the irritant and allergenic properties of fungi, early-life elevated dust yeast exposures or their components may be protective against allergy and asthma in children at risk for these outcomes. Ascertainment of fungal components associated with immunoprotective effects may have therapeutic relevance for asthma.

Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density

Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast cancer risk, and was increased in stromal cells in high MD tissues in one study. Our study assessed differential Cox-2 expression in epithelial and stromal cells in paired samples of high and low MD human breast tissue, and in a validated xenograft biochamber model of MD. We also examined the effects of endocrine treatment upon Cox-2 expression in high and low MD tissues in the MD xenograft model. Paired high and low MD human breast tissue samples were immunostained for Cox-2, then assessed for differential expression and staining intensity in epithelial and stromal cells. High and low MD human breast tissues were separately maintained in biochambers in mice treated with Tamoxifen, oestrogen or placebo implants, then assessed for percentage Cox-2 staining in epithelial and stromal cells. Percentage Cox-2 staining was greater for both epithelial (p = 0.01) and stromal cells (p < 0.0001) of high compared with low MD breast tissues. In high MD biochamber tissues, percentage Cox-2 staining was greater in stromal cells of oestrogen-treated versus placebo-treated tissues (p = 0.05).

A side-by-side comparison of three allergen sampling methods in settled house dust

Understanding allergen exposure and potential relationships with asthma requires allergen sampling methods, but methods have yet to be standardized. We compared allergen measurements from dust collected from 200 households with asthmatics and conducted a side-by-side vacuum sampling of settled dust in each home's kitchen, living room and subject's bedroom by three methods (EMM, HVS4 and AIHA). Each sample was analyzed for dust mite, cockroach, mouse, rat, cat and dog allergens. The number of samples with sufficient dust mass for allergen analysis was significantly higher for Eureka Mighty Mite (EMM) and high volume small surface sampler (HVS4) compared with American Industrial Hygiene Association (AIHA) in all rooms and surfaces tested (all P<0.05). The allergen concentration (weight of allergen divided by total weight of dust sampled) measured by the EMM and HVS4 methods was higher than that measured by the AIHA. Allergen loadings (weight of allergen divided by surface area sampled) were significantly higher for HVS4 than for AIHA and EMM. Cockroach and rat allergens were rarely detected via any method. The EMM method is most likely to collect sufficient dust from surfaces in the home and is relatively practical and easy. The AIHA and HVS4 methods suffer from insufficient dust collection and/or difficulty in use.

Incorporating community-based participatory research principles into environmental health research: challenges and lessons learned from a housing pilot study

In environmental health research, a community-based participatory research (CBPR) approach can effectively involve community members, researchers, and representatives from nonprofit, academic, and governmental agencies as equal partners throughout the research process. The authors sought to use CBPR principles in a pilot study; its purpose was to investigate how green construction practices might affect indoor exposures to chemicals and biological agents. Information from this pilot informed the development of a methodology for a nationwide study of low-income urban multifamily housing. The authors describe here 1) the incorporation of CBPR principles into a pilot study comparing green vs. conventionally built urban housing, 2) the resulting implementation and reporting challenges, and 3) lessons learned and implications for increased community participation in environmental health research.

Mammographic density-a review on the current understanding of its association with breast cancer

There has been considerable recent interest in the genetic, biological and epidemiological basis of mammographic density (MD), and the search for causative links between MD and breast cancer (BC) risk. This report will critically review the current literature on MD and summarize the current evidence for its association with BC. Keywords 'mammographic dens*', 'dense mammary tissue' or 'percent dens*' were used to search the existing literature in English on PubMed and Medline. All reports were critically analyzed. The data were assigned to one of the following aspects of MD: general association with BC, its relationship with the breast hormonal milieu, the cellular basis of MD, the generic variations of MD, and its significance in the clinical setting. MD adjusted for age, and BMI is associated with increased risk of BC diagnosis, advanced tumour stage at diagnosis and increased risk of both local recurrence and second primary cancers. The MD measures that predict BC risk have high heritability, and to date several genetic markers associated with BC risk have been found to also be associated with these MD risk predictors. Change in MD could be a predictor of the extent of chemoprevention with tamoxifen. Although the biological and genetic pathways that determine and perhaps modulate MD remain largely unresolved, significant inroads are being made into the understanding of MD, which may lead to benefits in clinical screening, assessment and treatment strategies. This review provides a timely update on the current understanding of MD's association with BC risk.

Association between birthplace and current asthma: the role of environment and acculturation

OBJECTIVES

We evaluated associations between current asthma and birthplace among major racial/ethnic groups in the United States.

METHODS

We used multivariate logistic regression methods to analyze data on 102,524 children and adolescents and 255,156 adults in the National Health Interview Survey (2001-2009).

RESULTS

We found significantly higher prevalence (P < .05) of current asthma among children and adolescents (9.3% vs 5.1%) and adults (7.6% vs 4.7%) born in the 50 states and Washington, DC (US-born), than among those born elsewhere. These differences were among all age groups of non-Hispanic Whites, non-Hispanic Blacks, and Hispanics (excluding Puerto Ricans) and among Chinese adults. Non-US-born adults with 10 or more years of residency in the United States had higher odds of current asthma (odds ratio = 1.55; 95% confidence interval = 1.25, 1.93) than did those who arrived more recently. Findings suggested a similar trend among non-US-born children.

CONCLUSIONS

Current asthma status was positively associated with being born in the United States and with duration of residency in the United States. Among other contributing factors, changes in environment and acculturation may explain some of the differences in asthma prevalence.

Environmental assessment and exposure reduction of cockroaches: a practice parameter

This parameter was developed by the Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma & Immunology (AAAAI); the American College of Allergy, Asthma & Immunology (ACAAI); and the Joint Council of Allergy, Asthma & Immunology. The AAAAI and the ACAAI have jointly accepted responsibility for establishing "Environmental assessment and remediation: a practice parameter." This is a complete and comprehensive document at the current time. The medical environment is a changing environment, and not all recommendations will be appropriate for all patients. Because this document incorporated the efforts of many participants, no single person, including those who served on the Joint Task Force, is authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information about or an interpretation of these practice parameters by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, the ACAAI, and the Joint Council of Allergy, Asthma & Immunology. These parameters are not designed for use by pharmaceutical companies in drug promotion. The findings and conclusions in this manuscript are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention (CDC).

Sociocultural characteristics, obesity and inflammatory biomarkers in Puerto Rican toddlers born in New York City

BACKGROUND

In the USA, Puerto Rican children have a higher prevalence of asthma than other Latino ethnicities, and acculturation is one of hypothesized reasons for this difference. We examined associations between sociocultural characteristics and serum leptin, high-sensitivity C-reactive protein (hsCRP), and body mass index (BMI), and further, among hsCRP, leptin levels, BMI percentiles, and allergic sensitization in 2-year-old children.

METHODS

IgE antibodies, leptin, and hsCRP concentrations were measured in serum from Puerto Rican toddlers (n = 143) born in New York City with a maternal history of allergy and/or asthma. Demographic and home characteristics questionnaires were administered to the mother, postpartum and two years later. Children's weight and height were measured to determine BMI percentiles.

RESULTS

More girls (60%) had leptin levels above the median compared with boys (37%) (p = 0.0063). Leptin was positively correlated with BMI (r = 0.25; p = 0.0042). Children in daycare were more likely to be obese (40% vs. 24% p < 0.06). Maternal birthplace was significantly associated with children's leptin but not with hsCRP. Leptin levels were lower for children whose mothers were born on the US mainland (GM = 2.5 ng/ml, 95% CI [2.2-2.7]) compared with those whose mothers were born in Puerto Rico or another country (GM = 3.2 ng/ml, 95% CI [2.2-3.9], t-test p = 0.01). Mothers born in another country were more likely than those born in the US mainland or Puerto Rico to have obese children (60% vs. 26% p < 0.02). Leptin, hsCRP, and BMI percentile were not associated with sensitization to any of the measured inhalant allergens or total IgE.

CONCLUSION

Even at a very young age, some acculturation factors were associated with biomarkers and anthropometric measures of obesity among this Puerto Rican pediatric population. To our knowledge, this is the first study demonstrating the association of mother's birth place with child BMI and leptin as early as 24 months.

Meteorological factors and ambient bacterial levels in a subtropical urban environment

We conducted a study to investigate the characteristics and determinants of ambient bacteria in Taipei, Taiwan from August 2004 to March 2005. We monitored ambient culturable bacteria in Shin-Jhuang City, an urban area in the Taipei metropolitan areas, using duplicate Burkard Portable Air Samplers with R2A agar. The average concentration of total bacteria was 1,986 colony-forming units per cubic meter of air (CFU/m(3)) (median = 780 CFU/m(3)) over the study period, with the highest level in autumn. Most bacterial taxa had similar seasonal variation, with higher concentrations in autumn and winter. During the study period, Gram negative rods and cocci were predominant. Multivariate analyses indicated that wind speed and wind direction significantly influenced ambient bacterial distribution. Temperature and relative humidity were also important environmental factors positively associated with ambient bacterial concentrations. We observed statistically significant relationships between ambient bacteria and air pollutants, including sulfur dioxide (SO(2)), ozone, particulate matter (aerodynamic diameter ≤10 μm (PM(10))), methane and total hydrocarbons. The concentrations of methane and total hydrocarbons during the previous day were positively associated with total bacteria and Gram negative rods, respectively. Ozone level on the previous day had a negative relationship with Gram negative cocci. SO(2) level with a 3-day lag was positively correlated with concentrations of both total bacteria and Gram negative cocci. In the future, more longitudinal studies are needed to confirm the relationships and possible mechanisms between ambient bacteria and meteorological factors, as well as to evaluate the ecological and health impacts of ambient bacteria.

Quantitative measurement of airborne cockroach allergen in New York City apartments

We designed and tested a sampling and analysis system for quantitative measurement of airborne cockroach allergen with sufficient sensitivity for residential exposure assessment. Integrated 1-week airborne particle samples were collected at 10-15 LPM in 19 New York City apartments in which an asthmatic child who was allergic to cockroach allergen resided. Four simultaneous air samples were collected in each home: at heights of 0.3 and 1 m in the child's bedroom and in the kitchen. Extracts of air samples were analyzed by ELISA for the cockroach allergen Bla g2, modified by amplifying the colorimetric signal generated via use of AMPLI-Q detection system (DAKO Corporation, Carpinteria, CA, USA). Settled dust samples were quantified by conventional ELISA. Of the homes where cockroach allergen was detected in settled dust, Bla g2 also was detected in 87% and 93% of air samples in the bedroom and kitchen, respectively. Airborne Bla g2 levels were highly correlated within and between the bedroom and kitchen locations (P < 0.001). Expressed as picogram per cubic meter, the room average geometric mean for Bla g2 concentrations was 1.9 pg/m³ (95% CI 0.63, 4.57) and 3.8 pg/m³ (95% CI 1.35, 9.25) in bedrooms and kitchens, respectively. This method offers an attractive supplement to settled dust sampling for cockroach allergen exposure health studies.

PRACTICAL IMPLICATIONS

Until now, cockroach allergen exposures have usually been assessed by collection and analysis of settled dust, on the assumption that airborne cockroach allergen cannot be reliably measured. In this study, a sensitive and quantitative method for measuring indoor airborne exposures to cockroach allergens involving a 7-day integrated total suspended particulate (TSP) sample collected at approximately 10-15 l/min was developed. Investigators are now empowered with an alternative exposure assessment method to supplement their studies and the understanding of allergen aerodynamics in the homes of children with asthma. We report airborne cockroach allergen in apartments, suggesting an ongoing burden of inhalation exposure.

Neighborhood differences in exposure and sensitization to cockroach, mouse, dust mite, cat, and dog allergens in New York City

BACKGROUND

Asthma prevalence varies widely among neighborhoods within New York City. Exposure to mouse and cockroach allergens has been suggested as a cause.

OBJECTIVE

To test the hypotheses that children living in high asthma prevalence neighborhoods (HAPNs) would have higher concentrations of cockroach and mouse allergens in their homes than children in low asthma prevalence neighborhoods (LAPNs), and that these exposures would be related to sensitization and asthma.

METHODS

In the New York City Neighborhood Asthma and Allergy Study, a case-control study of asthma, children 7 to 8 years old from HAPNs (n = 120) and LAPNs (n = 119) were recruited through the same middle-income health insurance plan. Children were classified as asthma cases (n = 128) or controls without asthma (n = 111) on the basis of reported symptoms or medication use. Allergens were measured in bed dust.

RESULTS

HAPN homes had higher Bla g 2 (P = .001), Mus m 1 (P = .003), and Fel d 1 (P = .003) and lower Der f 1 (P = .001) than LAPN homes. Sensitization to indoor allergens was associated with asthma, but relevant allergens differed between LAPNs and HAPNs. Sensitization to cockroach was more common among HAPN than LAPN children (23.7% vs 10.8%; P = .011). Increasing allergen exposure was associated with increased probability of sensitization (IgE) to cockroach (P < .001), dust mite (P = .009), and cat (P = .001), but not mouse (P = .58) or dog (P = .85).

CONCLUSION

These findings further demonstrate the relevance of exposure and sensitization to cockroach and mouse in an urban community and suggest that cockroach allergen exposure could contribute to the higher asthma prevalence observed in some compared with other New York City neighborhoods.

Exhaled NO among inner-city children in New York City

BACKGROUND

Fractional exhaled nitric oxide (FeNO) has been proposed as a biomarker of airway inflammation for cohort studies of asthma.

OBJECTIVES

To assess the association between FeNO and asthma symptoms among 7-year-old children living in an inner-city community. To test the association between environmental tobacco smoke (ETS) exposure (previous and current) and FeNO among these children.

METHODS

As part of a longitudinal study of asthma, children recruited in Head Start centers at age 4 had offline FeNO and lung function testing at age 7. Children with allergen-specific immunoglobulin E (IgE) (≥0.35 IU/mL) at age 7 were considered seroatopic. ETS exposure at ages 4 and 7 was assessed by questionnaire.

RESULTS

Of 144 participating children, 89 had complete questionnaire data and achieved valid FeNO and lung function tests. Children with reported wheeze in the previous 12 months (n = 19) had higher FeNO than those without wheeze (n = 70) (geometric means 17.0 vs. 11.0 ppb, p = .005). FeNO remained significantly associated with wheeze (p = .031), after adjusting for seroatopy and forced expiratory volume in 1 second (FEV₁) in multivariable regression. FeNO at age 7 was positively associated with domestic ETS exposure at age 4 (29%) (β = 0.36, p = .015) but inversely associated with ETS exposure at age 7 (16%) (β = -0.74, p < .001).

CONCLUSIONS

Given its association with current wheeze, independent of seroatopy and lung function, FeNO provides a relevant outcome measure for studies in inner-city communities. While compelling, the positive association between ETS exposure at age 4 and a marker of airway inflammation at age 7 should be confirmed in a larger study.

Exposure matrices of endotoxin, (1→3)-β-d-glucan, fungi, and dust mite allergens in flood-affected homes of New Orleans

This study examined: (i) biocontaminant levels in flooded homes of New Orleans two years after the flooding; (ii) seasonal changes in biocontaminant levels, and (iii) correlations between biocontaminant levels obtained by different environmental monitoring methods. Endotoxin, (1→3)-β-d-glucan, fungal spores, and dust mite allergens were measured in 35 homes during summer and winter. A combination of dust sampling, aerosolization-based microbial source assessment, and long-term inhalable bioaerosol sampling aided in understanding exposure matrices. On average, endotoxin found in the aerosolized fraction accounted for <2% of that measured in the floor dust, suggesting that vacuuming could overestimate inhalation exposures. In contrast, the (1→3)-β-d-glucan levels in the floor dust and aerosolized fractions were mostly comparable, and 25% of the homes showed aerosolizable levels even higher than the dust-borne levels. The seasonal patterns for endotoxin in dust and the aerosolizable fraction were different from those found for (1→3)-β-d-glucan, reflecting the temperature and humidity effects on bacterial and fungal contamination. While the concentration of airborne endotoxin followed the same seasonal trend as endotoxin aerosolized from surfaces, no significant seasonal difference was identified for the concentrations of airborne (1→3)-β-d-glucan and fungal spores. This was attributed to the difference in the particle size; smaller endotoxin-containing particles can remain airborne for longer time than larger fungal spores or (1→3)-β-d-glucan-containing particles. It is also possible that fungal aerosolization in home environments did not reach its full potential. Detectable dust mite allergens were found only in dust samples, and more commonly in occupied homes. Levels of endotoxin, (1→3)-β-d-glucan, and fungi in air had decreased during the two-year period following the flooding as compared to immediate measurements; however, the dust-borne endotoxin and (1→3)-β-d-glucan levels remained elevated. No conclusive correlations were found between the three environmental monitoring methods. The findings support the use of multiple methods when assessing exposure to microbial contaminants.

Cord blood versus age 5 mononuclear cell proliferation on IgE and asthma

BACKGROUND

Fetal immune responses following exposure of mothers to allergens during pregnancy may influence the subsequent risk of childhood asthma. However, the association of allergen-induced cord blood mononuclear cell (CBMC) proliferation and cytokine production with later allergic immune responses and asthma has been controversial. Our objective was to compare indoor allergen-induced CBMC with age 5 peripheral blood mononuclear cell (PBMC) proliferation and determine which may be associated with age 5 allergic immune responses and asthma in an inner city cohort.

METHODS

As part of an ongoing cohort study of the Columbia Center for Children's Environmental Health (CCCEH), CBMCs and age 5 PBMCs were cultured with cockroach, mouse, and dust mite protein extracts. CBMC proliferation and cytokine (IL-5 and IFN-gamma) responses, and age 5 PBMC proliferation responses, were compared to anti-cockroach, anti-mouse, and anti-dust mite IgE levels, wheeze, cough, eczema and asthma.

RESULTS

Correlations between CBMC and age 5 PBMC proliferation in response to cockroach, mouse, and dust mite antigens were nonsignificant. Cockroach-, mouse-, and dust mite-induced CBMC proliferation and cytokine responses were not associated with allergen-specific IgE at ages 2, 3, and 5, or with asthma and eczema at age 5. However, after adjusting for potential confounders, age 5 cockroach-induced PBMC proliferation was associated with anti-cockroach IgE, total IgE, and asthma (p < 0.05).

CONCLUSION

In contrast to allergen-induced CBMC proliferation, age 5 cockroach-induced PBMC proliferation was associated with age 5 specific and total IgE, and asthma, in an inner-city cohort where cockroach allergens are prevalent and exposure can be high.

Pest and allergen exposure and abatement in inner-city asthma: a work group report of the American Academy of Allergy, Asthma & Immunology Indoor Allergy/Air Pollution Committee

Our work group report details the importance of pest allergen exposure in inner-city asthma. We will focus specifically on mouse and cockroach exposure. We will discuss how exposure to these pests is common in the inner city and what conditions exist in urban areas that might lead to increased exposure. We will discuss how exposure is associated with allergen sensitization and asthma morbidity. Finally, we will discuss different methods of intervention and the effectiveness of these tactics.

Are neighborhood-level characteristics associated with indoor allergens in the household?

BACKGROUND

Individual home characteristics have been associated with indoor allergen exposure; however, the influence of neighborhood-level characteristics has not been well studied. We defined neighborhoods as community districts determined by the New York City Department of City Planning.

OBJECTIVE

We examined the relationship between neighborhood-level characteristics and the presence of dust mite (Der f 1), cat (Fel d 1), cockroach (Bla g 2), and mouse (MUP) allergens in the household.

METHODS

Using data from the Puerto Rican Asthma Project, a birth cohort of Puerto Rican children at risk of allergic sensitization (n = 261), we examined associations between neighborhood characteristics (percent tree canopy, asthma hospitalizations per 1,000 children, roadway length within 100 meters of buildings, serious housing code violations per 1000 rental units, poverty rates, and felony crime rates), and the presence of indoor allergens. Allergen cutpoints were used for categorical analyses and defined as follows: dust mite: >0.25 microg/g; cat: >1 microg/g; cockroach: >1 U/g; mouse: >1.6 microg/g.

RESULTS

Serious housing code violations were statistically significantly positively associated with dust mite, cat, and mouse allergens (continuous variables), adjusting for mother's income and education, and all neighborhood-level characteristics. In multivariable logistic regression analyses, medium levels of housing code violations were associated with higher dust mite and cat allergens (1.81, 95%CI: 1.08, 3.03 and 3.10, 95%CI: 1.22, 7.92, respectively). A high level of serious housing code violations was associated with higher mouse allergen (2.04, 95%CI: 1.15, 3.62). A medium level of housing code violations was associated with higher cockroach allergen (3.30, 95%CI: 1.11, 9.78).

CONCLUSIONS

Neighborhood-level characteristics, specifically housing code violations, appear to be related to indoor allergens, which may have implications for future research explorations and policy decisions.

Housing and allergens: a pooled analysis of nine US studies

BACKGROUND

Housing conditions can contribute to allergen exposures that are linked to asthma, but little is known about which of those conditions are most likely to predict high levels of allergens in settled house dust.

METHODS

We pooled allergen, housing condition, occupant behavior, demographic, and other data from nine asthma studies (n=950 homes in 6 US cities). Dust mite (Der f 1 or Der p 1), cockroach (Bla g 1 or Bla g 2), mouse (Mus m 1), cat (Fel d 1) and dog (Can f 1) allergens were measured in settled dust from kitchens or bedrooms, and concentrations were categorized according to previously published asthma symptom thresholds. We calculated odds ratios (OR) using logistic regression to identify those housing conditions and occupant behaviors that were associated with clinically significant allergen levels, after adjusting for numerous confounding variables.

RESULTS

The adjusted results show that high cockroach allergen was associated with cracks or holes in walls (OR=2.1), high dust mite allergen was associated with mold odor (OR=2.5), housing built before 1951 (OR=2.1), and single-family home with slab on grade (OR=1.9); and mouse allergen was associated with rodent control or signs of rodents (OR=3.62) and inversely associated with presence of a cat (OR=0.20). Water leaks and below average housekeeping had unadjusted high odds ratios for high cockroach allergen.

CONCLUSION

We have identified a number of housing conditions that are consistently associated with increased allergen dust concentrations. This study indicates that screening for housing-based asthma triggers should include presence of cats, dogs, cockroaches, or rodents; water leaks; mold or mold odor; holes or cracks in walls; and below average housekeeping. Single family houses that have basements or crawl spaces or are built before 1951 are also important predictors for increased allergens in housing.

Surveillance of Fungal Allergic Sensitization Using the Fluorescent Halogen Immunoassay

OBJECTIVE: Conidia derived from a small number of common fungal genera are widely accepted as the etiological agents responsible for fungal allergic sensitization. The contribution of fungal conidia, spores, airborne hyphae, and subcellular fragments from other uncharacterized fungal genera remains unclear. In this proof-of-concept study, we examined the composition of mycoaerosols that atopic women were exposed and sensitized to in their own indoor environment using the fluorescent halogen immunoassay (fHIA). PATIENTS AND METHODS: Mycoaerosols were collected onto mixed cellulose ester protein binding membranes (PBMs) for 30 minutes with volumetric air sampling pumps. The PBMs were laminated with an adhesive cover slip and indirectly immunostained with individual patient serum IgE using the fHIA. Samples were examined using confocal laser scanning microscopy and immunostained particles were expressed as a percentage of total particles. RESULTS: All air samples contained a broad spectrum of fungal spores, conidia, hyphae, and other fungal particulates. Airborne concentrations varied between individual study participant environments. Positively immunostained conidia belonging to moniliaceous amerospores, Cladosporium, Alternaria, and many unknown species were observed in the majority of air samples. Other fungal genera including Bipolaris, Curvularia, Pithomyces, and Stachybotrys, in addition to, ascospore genera and dematiaceous hyphal fragments released detectable allergen. Twelve percent of all fHIA haloes quantified in the analysis were directed towards fungal particles. No immunostaining was detected to conidia belonging to Epicoccum, Fusarium, and Spegazzinia species. CONCLUSION: In addition to characterized fungal aeroallergens, we observed a wider composition of fungi that bound human IgE. Field surveillance studies that utilize immunodiagnostic techniques such as the fHIA will provide further insight into the diversity of fungi that function as aeroallergen sources in individual study participant environments.

Prenatal acetaminophen exposure and risk of wheeze at age 5 years in an urban low-income cohort

BACKGROUND

Acetaminophen has been associated with asthma and is in part metabolised via the glutathione pathway. Inner-city minority children have high asthma morbidity and a relatively high frequency of a minor allele variant in the glutathione S transferase Pi gene (GSTP1). We hypothesised that prenatal acetaminophen exposure would predict wheeze at age 5 years in an inner-city minority cohort and examined whether this association was modified by common polymorphisms in genes related to the glutathione pathway.

METHODS

An ongoing population-based birth cohort study of Dominican Republic and African-American children in New York prospectively assessed the use of analgesics during pregnancy and current wheeze at age 5 years in 301 children. Genotyping was conducted for GST polymorphisms. Binomial regression was used to adjust for potential confounders including postnatal acetaminophen use.

RESULTS

34% of mothers reported acetaminophen use during pregnancy and 27% of children had current wheeze at 5 years. Prenatal exposure to acetaminophen predicted current wheeze (multivariate relative risk 1.71; 95% CI 1.20 to 2.42; p=0.003), and the risk increased monotonically with increasing number of days of prenatal acetaminophen exposure (p trend <0.001). 68% of children had at least one copy of the GSTP1 minor allele (Val). The risk of wheeze was modified by GSTP1 (additive interaction p=0.009) and was observed only among children with the GSTP1 minor allele.

CONCLUSIONS

Prenatal exposure to acetaminophen predicted wheeze at age 5 years in an inner-city minority cohort. The risk was modified by a functional polymorphism in GSTP1, suggesting a mechanism involving the glutathione pathway.

Prenatal acetaminophen exposure and risk of wheeze at age 5 years in an urban low-income cohort

BACKGROUND

Acetaminophen has been associated with asthma and is in part metabolised via the glutathione pathway. Inner-city minority children have high asthma morbidity and a relatively high frequency of a minor allele variant in the glutathione S transferase Pi gene (GSTP1). We hypothesised that prenatal acetaminophen exposure would predict wheeze at age 5 years in an inner-city minority cohort and examined whether this association was modified by common polymorphisms in genes related to the glutathione pathway.

METHODS

An ongoing population-based birth cohort study of Dominican Republic and African-American children in New York prospectively assessed the use of analgesics during pregnancy and current wheeze at age 5 years in 301 children. Genotyping was conducted for GST polymorphisms. Binomial regression was used to adjust for potential confounders including postnatal acetaminophen use.

RESULTS

34% of mothers reported acetaminophen use during pregnancy and 27% of children had current wheeze at 5 years. Prenatal exposure to acetaminophen predicted current wheeze (multivariate relative risk 1.71; 95% CI 1.20 to 2.42; p=0.003), and the risk increased monotonically with increasing number of days of prenatal acetaminophen exposure (p trend <0.001). 68% of children had at least one copy of the GSTP1 minor allele (Val). The risk of wheeze was modified by GSTP1 (additive interaction p=0.009) and was observed only among children with the GSTP1 minor allele.

CONCLUSIONS

Prenatal exposure to acetaminophen predicted wheeze at age 5 years in an inner-city minority cohort. The risk was modified by a functional polymorphism in GSTP1, suggesting a mechanism involving the glutathione pathway.

Mite sensitization among Latina women in New York, where dust-mite allergen levels are typically low

In New York (NY), Latinos often have greater asthma morbidity than other ethnicities, and dust-mite sensitization is common despite low allergen levels. We investigated mite allergen exposure and sensitization in atopic and/or asthmatic women, the majority being Puerto Rican. Women (n = 274) recruited for a birth cohort study were visited postnatally. Dust from their homes was analyzed for mite allergens (Der f 1, Der p 1, and Blo t 5). Serum was analyzed for total and allergen-specific IgE. Thirty-seven percent were sensitized to Dermatophagoides pteronyssinus, 34% to Dermatophagoides farinae, and 21% to Blomia tropicalis. Only 5% of NY homes had levels of Der f 1 >2 microg/g; none had Blo t 5 or Der p 1 above this level. Caribbean or Latin American birthplace (a proxy for childhood exposure) was not associated with mite sensitization. Sensitization to D. pteronyssinus and D. farinae was associated with a report of doctor-diagnosed asthma [Odds ratio (OR) = 3.27, P = 0.003; OR = 2.81, P = 0.010, respectively]; sensitization to any mite was associated with asthma medication use in the past 12 months (OR = 3.12, P = 0.004). These associations held even after adjustment for cockroach, mouse, and cat sensitization.

PRACTICAL IMPLICATIONS

Despite the low concentrations of mite allergen in our community, many of the women in the atopically enriched cohort were sensitized to mites, even Blomia tropicalis which is typically found only in tropical environments.

Aerosolization of fungi, (1-->3)-beta-D glucan, and endotoxin from flood-affected materials collected in New Orleans homes

Standing water and sediments remaining on flood-affected materials were the breeding ground for many microorganisms in flooded homes following Hurricane Katrina. The purpose of this laboratory study was to examine the aerosolization of culturable and total fungi, (1-->3)-beta-D glucan, and endotoxin from eight flood-affected floor and bedding materials collected in New Orleans homes, following Hurricane Katrina. Aerosolization was examined using the Fungal Spore Source Strength Tester (FSSST) connected to a BioSampler. Dust samples were collected by vacuuming. A two-stage cyclone sampler was used for size-selective analysis of aerosolized glucan and endotoxin. On average, levels of culturable fungi ranged from undetectable (lower limit=8.3 x 10(4)) to 2.6 x 10(5) CFU/m(2); total fungi ranged from 2.07 x 10(5) to 1.6 x 10(6) spores/m(2); (1-->3)-beta-D glucan and endotoxin were 2.0 x 10(3) - 2.9 x 10(4) ng/m(2) and 7.0 x 10(2) - 9.3 x 10(4) EU/m(2), respectively. The results showed that 5-15 min sampling is sufficient for detecting aerosolizable biocontaminants with the FSSST. Smaller particle size fractions (<1.0 and <1.8 microm) have levels of glucan and endotoxin comparable to larger (>1.8 microm) fractions, which raises additional exposure concerns. Vacuuming was found to overestimate inhalation exposure risks by a factor of approximately 10(2) for (1-->3)-beta-D glucan and by 10(3)-10(4) for endotoxin as detected by the FSSST. The information generated from this study is important with respect to restoration and rejuvenation of the flood-affected areas in New Orleans. We believe the findings will be significant during similar disasters in other regions of the world including major coastal floods from tsunamis.

Anti-cockroach and anti-mouse IgE are associated with early wheeze and atopy in an inner-city birth cohort

BACKGROUND

The relationships between cockroach and mouse allergen exposure, anti-cockroach and anti-mouse IgE, and wheeze, rhinitis, and atopic dermatitis in children as young as age 3 years are of public health importance but have not been thoroughly evaluated.

OBJECTIVE

We hypothesized that inner-city children might have anti-cockroach and anti-mouse IgE by age 3 years, and their presence would be associated with respiratory and atopic symptoms.

METHODS

Children were followed prospectively from birth through age 3 years (n = 404). Residential levels of cockroach and mouse allergens, sera levels of anti-cockroach and anti-mouse IgE, and parental report of wheeze, rhinitis, and atopic dermatitis were measured.

RESULTS

The odds of early wheeze were significantly higher among children who had IgE to cockroach (odds ratio [OR], 3.3; 95% CI, 1.8-6.2), mouse (OR, 4.6; 95% CI, 2.3-9.0), or both (OR, 9.7; 95% CI, 3.4-27.3). The odds of rhinitis or atopic dermatitis were also higher among children with IgE to cockroach, mouse, or both. Higher IgE class to cockroach and mouse was associated with wheeze and atopic dermatitis (tests for trend, P < .002).

CONCLUSIONS

Children age 2 to 3 years who have anti-cockroach and anti-mouse IgE are at increased risk of wheeze and atopy. Moreover, a dose-response relationship was found between higher IgE class and increased prevalence of wheeze, rhinitis, or atopic dermatitis. These findings indicate the importance of reducing exposure to cockroach and mouse allergens for susceptible children.

Effects of winter birth season and prenatal cockroach and mouse allergen exposure on indoor allergen-specific cord blood mononuclear cell proliferation and cytokine production

BACKGROUND

Season of birth has been associated with the development of atopy and asthma. Relationships among a particular birth season, maternal allergen exposure during the birth season, and childhood development of allergies to allergens in higher concentration during the birth season may be important.

OBJECTIVE

To investigate the effects of winter birth (January 1 to March 31) and prenatal cockroach and mouse allergens in settled dust on indoor allergen-specific cord blood mononuclear cell (CBMC) proliferation, TH2 production, and cord blood IgE concentration.

METHODS

As part of an ongoing prospective study, 350 cord blood samples were collected. The CBMCs were cultured with cockroach, dust mite, and mouse protein extracts, and proliferation was measured. Interleukin 5, interferon-delta, and total IgE levels were measured. Home dust samples were analyzed for cockroach and mouse allergens.

RESULTS

An isolated association was observed between winter birth and a greater mean (SD) cockroach interleukin 5 ratio (winter vs nonwinter birth: 26,043 [11,403] vs 11,344 [3,701]; P = .02). Other associations between winter birth and increased CBMC proliferation, T-helper cytokines, or cord blood IgE levels were not detected. Higher mouse allergen levels were associated with decreased mouse-induced proliferation (winter vs nonwinter birth: mean [SD] stimulation index, 1.72 [0.12] vs 2.02 [0.11]; P = .04).

CONCLUSIONS

Winter birth and increased cockroach or mouse allergen levels during pregnancy were not consistently associated with greater CBMC proliferation, T-helper cytokine production, or cord blood IgE levels. Greater indoor allergen exposure during pregnancy does not seem to affect the development of cockroach or mouse immune responses in utero.

Cat ownership is a risk factor for the development of anti-cat IgE but not current wheeze at age 5 years in an inner-city cohort

BACKGROUND

Cat ownership is inversely associated with atopy and asthma in some areas of the world, but the relevance of cat ownership to allergic disease in the inner city is less known.

OBJECTIVE

We sought to evaluate the relationship between cat ownership and the development of early sensitization and wheeze.

METHODS

By using a prospective birth cohort study, Dominican and African American mothers living in New York City underwent repeated questionnaires about their child from birth to age 5 years. Sera collected from children at ages 2 (n = 323), 3 (n = 336), and 5 (n = 242) years were assayed for anti-cat IgE and anti-Fel d 1 IgG antibodies.

RESULTS

Cat ownership was a significant risk factor for the development of anti-cat IgE by age 2 years (risk ratio [RR], 6.4; 95% CI, 1.9-22) but not for anti-cat IgE development between the ages of 2 and 5 years (RR, 0.88; 95% CI, 0.24-2.3). Current wheeze was significantly more common among those children with anti-cat IgE at ages 3 (RR, 3.5; 95% CI, 2.1-6.0) and 5 (RR, 3.4; 95% CI, 2.3-4.9) years. Cat ownership was inversely associated with current wheeze at age 5 years among children without anti-cat IgE (RR, 0.26; 95% CI, 0.083-0.81). Among children with anti-cat IgE, a similar trend was observed (RR, 0.57; P = .044, Fisher exact test), although one with borderline statistical significance.

CONCLUSIONS

Despite a positive association with sensitization, cat ownership in this inner-city cohort was inversely associated with wheeze, potentially suggesting an IgE-independent protective mechanism in this community.