ClinicalTrials.gov
 Home    Search    Study Topics    Glossary  
 

  Full Text View  
  Tabular View  
  Contacts and Locations  
  Related Studies  
Biomarkers of Benzene Exposure in Inner City Residents

This study has been completed.
Information provided by National Institute of Environmental Health Sciences (NIEHS)

This Tabular View shows the required WHO registration data elements as marked by

Descriptive Information Fields
Brief Title  Biomarkers of Benzene Exposure in Inner City Residents
Official Title 
Brief Summary

This study compares air pollution exposures of residents in a South Baltimore community next to major industry with those in a comparison community with much less industry nearby. Parents and children as well as adults alone will be included. Air levels of 3 chemicals that have been found in increased amounts in the community as well as two urinary breakdown products of benzene will be measured. Participants will limit the amount of sorbate preserved foods they eat as this preservative interferes with one of the benzene breakdown products. Benzene air and urine exposure measurements will be compared in each community as well as between communities. By including children and parents we will gather exposure information on children who may be more sensitive that adults to these types of pollution. Lastly, by restricting the amount of food preserved with sorbates, we can decide if this improves the use of ttMA for people exposed to benzene from air pollution.

Detailed Description

The current study focuses on an environmental exposure assessment of a South Baltimore community residing near a heavily industrialized area. Exposure differences between this community and a reference community that is demographically similar to South Baltimore but has limited industrial impact will be assessed. Participants will include both parent child study pairs and adults. Outdoor, indoor and personal 72 hour badge monitoring for benzene, 1,3-butadiene and carbon tetrachloride will be performed. Two urinary biomarkers for benzene exposure, trans,trans-muconic acid (ttMA) and s-phenylmercapturic acid (S-PMA) will be measured at 3 daily time points over the 3 day period. Past work indicates that ingestion of sorbate preserved foods causes substantial interference with the benzene biomarker, ttMA. Therefore, participants will restrict their intake of sorbate preserved foods during the study. On the day of greatest dietary restriction, a 24 hour benzene personal air measurement will be obtained. Data analysis will include correlations of benzene badge exposure measurements and urinary biomarkers. Air and biomarker benzene exposure data will be compared between communities. Linear regression modeling will be used to determine important explanatory factors of the biomarkers. The inclusion of parent child study pairs will also allow correlation of benzene air levels and urinary biomarkers between parents and children. This will provide exposure information on a potentially susceptible subpopulation, e.g. children, and allow assessment of potential for age-related differences in benzene metabolism. Finally, we will be able to determine if dietary restriction is practical and results in greater specificity of ttMA as a benzene biomarker.

Study Phase
Study Type  Observational
Study Design  Screening, Cross-Sectional, Random Sample
Primary Outcome Measure 
Secondary Outcome Measure 
Condition  Lung Disease
Cancer
Intervention 
MEDLINE PMIDs 9646045,   8919771,   10919747
Links
Recruitment Information Fields
Recruitment Status  Completed
Enrollment  90
Start Date 
Completion Date
Eligibility Criteria 

residence in one of the study communities

Gender Both
Ages 3 Years and older
Accepts Healthy Volunteers Yes
Contacts ††
Location Countries  United States
Administrative Information Fields
NCT ID  NCT00014963
Organization ID 7780-CP-001
Secondary IDs ††
Study Sponsor  National Institute of Environmental Health Sciences (NIEHS)
Collaborators †† Mickey Leland National Urban Air Toxics Research Center
Environmental Protection Agency (EPA)
Investigators 
Information Provided By National Institute of Environmental Health Sciences (NIEHS)
Verification Date March 2006
First Received Date  April 16, 2001
Last Updated Date March 22, 2006

 †    Required WHO trial registration data element.
††   WHO trial registration data element that is required only if it exists.




Links to all studies - primarily for crawlers