Indoor exposures to air pollutants and allergens in the homes of asthmatic children in inner-city Baltimore.

This paper presents indoor air pollutant concentrations and allergen levels collected from the homes of 100 Baltimore city asthmatic children participating in an asthma intervention trial. Particulate matter (PM), NO2, and O3 samples were collected over 72 h in the child's sleeping room. Time-resolved PM was also assessed using a portable direct-reading nephelometer. Dust allergen samples were collected from the child's bedroom, the family room, and the kitchen. The mean PM10 concentration, 56.5+/-40.7 microg/m3, is 25% higher than the PM2.5 concentration (N=90), 45.1+/-37.5 microg/m3. PM concentrations measured using a nephelometer are consistent and highly correlated with gravimetric estimates. Smoking households' average PM2.5 and PM10 concentrations are 33-54 microg/m3 greater than those of nonsmoking houses, with each cigarette smoked adding 1.0 microm/m3 to indoor PM2.5 and PM10 concentrations. Large percentages of NO2 and O3 samples, 25% and 75%, respectively, were below the limit of detection. The mean NO2 indoor concentration is 31.6+/-40.2 ppb, while the mean indoor O3 concentration in the ozone season was 3.3+/-7.7 ppb. The levels of allergens are similar to those found in other inner cities. Results presented in this paper indicate that asthmatic children in Baltimore are exposed to elevated allergens and indoor air pollutants. Understanding this combined insult may help to explain the differential asthma burden between inner-city and non-inner-city children.

Methods and issues in conducting a community-based environmental randomized trial.

The environment is suspected to play an important role in the prevalence and severity of asthma in inner-city children. This paper describes the implementation and baseline data of an inner-city community-based participatory research clinical trial designed to test the effectiveness of a pollutant and allergen control strategy on children's asthma morbidity. Participants were 100 elementary-school-aged children with asthma, graduates of a school-based asthma education program in East Baltimore. The intervention for half of the randomly assigned families consisted of environmental control education, allergen-proof encasements, pest extermination, and a HEPA air cleaner at the beginning of the study. Controls received the same at the end of the study. Participants visited a clinic for questionnaires, allergy skin testing, spirometry, and blood sample at baseline and 12 months. Home environments, NO(2), O(3), airborne particulates, and allergens were evaluated at baseline and at 6 and 12 months. Asthma morbidity and adherence was assessed quarterly. Collaboration with the community proved very beneficial in creating a study design and procedures acceptable to an inner-city community.

Knowledge and practice of dust mite control by specialty care.

BACKGROUND: Dust mites are the primary indoor allergen risk for increasing asthma attacks and morbidity. Adherence to allergen avoidance recommendations decreases bronchial reactivity and asthma morbidity. OBJECTIVE: This study compared the knowledge and practice of environmental control advice of families of children with asthma seen by an allergist or a pediatrician. Studies suggest that knowledge and practice of environmental control recommendations is inconsistent. METHODS: Subjects were aged 6 to 17 years, diagnosed with asthma, and had positive skin test to dust mites. There were 114 eligible pediatric patients, and 69 had also seen an allergist before the study. An in-home evaluation was completed during which parents were asked about environmental control knowledge and practice. An environmental technician then completed a walk-through evaluation to observe which recommendations were implemented in the home. RESULTS: Families who saw an allergist demonstrated significantly greater awareness of environmental control recommendations for dust mite allergens than those who had not. Knowledge and placement of allergen-proof mattress and pillow covers was significantly higher in these families. However, 30% of families who saw an allergist reported no knowledge of any environmental control recommendations for dust mites. Less than half of the allergist families (48%) who were advised to use mattress encasements actually had encasements on their children's beds. CONCLUSIONS: The parents of dust mite-sensitive, asthmatic children who saw an allergist were more aware of dust mite allergen control recommendations and made more indoor environmental changes.