Science Inventory

MECHANISTIC INDICATORS OF CHILDHOOD ASTHMA (MICA)

Impact/Purpose:

Phase 1 of MICA includes an assessment gene expression data collected from rodent blood and respiratory tissues RNA produced by short-term controlled exposures to concentrated particulate matter. Mobile units housed with rodent exposure chambers (State University) were employed in Grand Rapids, Michigan and in the Detroit Metropolitan Area. Phase 1 will provide 1) information on the reliability of surrogate blood RNA samples to predict target tissues effects and 2) context for the human gene expression data, collected in phase 2 planned for the summer of 2006. Phase 2 is a children exposure assessment/biomarker study focusing on three broad classes of particulate associated chemicals: volatile organic compounds (VOCs), metals, and polycyclic aromatic hydrocarbons (PAHs). MICA will study 150 asthmatic and 50 non-asthmatic children. Blood and urinary measures of these chemicals will be compared to benchmark levels of these chemicals and metabolites from the Center for Disease Control and Prevention’s (CDC) National Exposure Report. MICA consists of clinical measurements including (a) a skin prick test for allergen sensitivity; (b) analysis of blood, urine, nail clippings, and DNA; (c) immunological markers, odor testing, lung function and breath analysis; (d) gene expression and protein tests, viewed in the context of environmental assessments and respiratory health history.

Description:

The US Environmental Protection Agency (EPA) is interested in the interplay of environmental and genetic factors on the development and exacerbation of asthma. The Mechanistic Indicators of Childhood Asthma (MICA) study will use exposure measurements and markers of environmental exposure and health effects. Based on epidemiological studies of air pollution and asthma, there is sufficient evidence to justify investigations that incorporate state-of-the art technologies including genomics and proteomics, to study how and which genes and environmental factors interact in a way that increases the risk of worsening asthmatic responses. EPA scientists will use collected markers of exposure and effects to analyze, characterize, and possibly quantify combined risk factors that relate to asthma severity from multiple agents/stressors. Our study will also provide information on some key molecular events associated with chemical exposures, giving risk assessors more reliable data to assist in defining exposure-response relationships and in making estimates on the range of risks expected in the population compared to data based on biological monitoring and/or screening level hazard data.

Record Details:

Record Type: PROJECT
Projected Completion Date: 09/30/2008
OMB Category: Other
Record ID: 149111

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL CENTER FOR COMPUTATIONAL TOXICOLOGY

IMMEDIATE OFFICE