Case-Control Study of Pesticides and Childhood Leukemia

This study has been completed.
Sponsor:
Information provided by:
National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier:
NCT00342888
First received: June 19, 2006
Last updated: June 21, 2014
Last verified: May 2014
  Purpose

Childhood leukemia is the most common type of childhood cancer and its etiology is largely unknown. Most case-control studies of childhood leukemia have reported elevated risks among children whose parents were occupationally exposed to pesticides or who used pesticides in the home or garden. Investigators at the University of California at Berkeley (UCB) conducted a case-control study of childhood leukemia in 35 counties in the San Francisco Bay area and the agricultural Central Valley of California. A major focus of the UCB study is to evaluate whether household or occupational exposure to pesticides increases the risk of childhood leukemia. Our collaboration provided additional funding to collect carpet dust samples for the measurement of pesticides and other chemicals. For 470 participants, we attempted to collect carpet dust using a special high volume small surface sampler (HVS3) vacuum and by taking dust from participants vacuum cleaner. As of July 2006, dust samples will be collected only from participant's vacuum cleaner. Samples were collected at a home visit approximately 3-6 months after the first in-person interview. We will also provide support for mapping of the crops (i.e., determining crop field boundaries and crop species) within 1200 meters (3/4 mile) of residences so that the residential proximity to agricultural fields treated with pesticides can be determined. We will conduct the epidemiologic analysis of pesticide and other chemical levels in carpet dust and risk of childhood leukemia. We will also evaluate whether residential proximity to agricultural pesticide use is associated with risk of leukemia. Further, we will conduct an Exposure Pilot Study that will include a subset of the study population. Two components of the Pilot Study will evaluate how well a used vacuum bag and a window sill wipe predict pesticide and other chemical concentrations in carpet dust samples collected with the more complicated HVS3 vacuum method. The third component will compare pesticides detected in carpet dust with pesticides predicted by geographic proximity to agriculture.


Condition
Leukemia

Study Type: Observational
Study Design: Time Perspective: Retrospective
Official Title: A Case-Control Study of Pesticides and Childhood Leukemia

Resource links provided by NLM:


Further study details as provided by National Institutes of Health Clinical Center (CC):

Primary Outcome Measures:
  • Risk factors for childhood leukemia. [ Time Frame: Data analysis still ongoing ] [ Designated as safety issue: No ]

Estimated Enrollment: 629
Study Start Date: October 2001
Detailed Description:

Childhood leukemia is the most common type of childhood cancer and its etiology is largely unknown. Most case-control studies of childhood leukemia have reported elevated risks among children whose parents were occupationally exposed to pesticides or who used pesticides in the home or garden. Investigators at the University of California at Berkeley (UCB) conducted a case-control study of childhood leukemia in 35 counties in the San Francisco Bay area and the agricultural Central Valley of California. A major focus of the UCB study was to evaluate whether household or occupational exposure to pesticides increases the risk of childhood leukemia. Our collaboration provided additional funding to collect carpet dust samples for the measurement of pesticides and other chemicals. For 470 participants, we attempted to collect carpet dust using a special high volume small surface sampler (HVS3) vacuum and by taking dust from participants vacuum cleaner. As of July 2006, dust samples were collected only from participant's vacuum cleaner. Samples were collected at a home visit approximately 3-6 months after the first in-person interview. We also provided support for mapping of the crops (i.e., determining crop field boundaries and crop species) within 1200 meters (3/4 mile) of residences so that the residential proximity to agricultural fields treated with pesticides can be determined. We will conduct the epidemiologic analysis of pesticide and other chemical levels in carpet dust and risk of childhood leukemia. We will also evaluate whether residential proximity to agricultural pesticide use is associated with risk of leukemia. Further, we will conduct an Exposure Pilot Study that will include a subset of the study population. Two components of the Pilot Study will evaluate how well a used vacuum bag and a window sill wipe predict pesticide and other chemical concentrations in carpet dust samples collected with the more complicated HVS3 vacuum method. The third component will compare pesticides detected in carpet dust with pesticides predicted by geographic proximity to agriculture.

  Eligibility

Ages Eligible for Study:   up to 8 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria
  • INCLUSION CRITERIA:

All cases and controls were selected from participants in the UCB case-control study who have completed the Tier I interview.

Study population is limited to children.

All races and ethnicities will be included in the study.

Tier I:

The cases eligible for participation in Tier I of the UCB study of all newly diagnosed cases of childhood leukemia 0-14 years old resident in 35 counties in San Francisco Bay Area and the Central Valley

Further inclusion criteria are no prior cancer diagnosis and at least one English or Spanish speaking parent.

Tier II:

Tier II participants will be selected from cases and controls that complete the Tier I interview. Cases (and their match controls), aged 0-7, diagnosed from December 1, 1999 through 2003, and who still reside at the home where they were living ate the diagnosis date, will be eligible for the Tier II interview.

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00342888

Locations
United States, California
University of California, Berkeley
Berkeley, California, United States, 94720-0001
Sponsors and Collaborators
Investigators
Principal Investigator: Mary Ward, Ph.D. National Cancer Institute (NCI)
  More Information

Publications:
ClinicalTrials.gov Identifier: NCT00342888     History of Changes
Obsolete Identifiers: NCT00556985
Other Study ID Numbers: 999902030, 02-C-N030
Study First Received: June 19, 2006
Last Updated: June 21, 2014
Health Authority: United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):
Childhood Cancer
Pesticides
Polychlorinated Biphenyls
Organochlorines
Polybrominated Diphenyl Ethers

Additional relevant MeSH terms:
Leukemia
Neoplasms by Histologic Type
Neoplasms

ClinicalTrials.gov processed this record on July 22, 2014