From: Robina Suwol
Date: 14 May 2004
Time: 08:05:19
Remote Name: 68.116.132.26
Critical Windows of Exposure to Household Pesticides and Risk of Childhood
Leukemia
Xiaomei Ma,1 Patricia A. Buffler,1 Robert B. Gunier,2 Gary Dahl,3 Martyn T.
Smith,1 Kyndaron Reinier,1 and Peggy Reynolds21School of Public Health,
University of California, Berkeley, California, USA; 2Environmental Health
Investigations Branch, California Department of Health Services, Oakland,
California, USA; 3Stanford University School of Medicine, Stanford, California,
USA
Abstract
The potential etiologic role of household pesticide exposures was examined in
the Northern California Childhood Leukemia Study. A total of 162 patients (0-14
years old) with newly diagnosed leukemia were rapidly ascertained during
1995-1999, and 162 matched control subjects were randomly selected from the
birth registry. The use of professional pest control services at any time from 1
year before birth to 3 years after was associated with a significantly increased
risk of childhood leukemia [odds ratio (OR) = 2.8; 95% confidence interval (CI),
1.4-5.7], and the exposure during year 2 was associated with the highest risk
(OR = 3.6; 95% CI, 1.6-8.3). The ORs for exposure to insecticides during the 3
months before pregnancy, pregnancy, and years 1, 2, and 3 were 1.8 (95% CI,
1.1-3.1), 2.1 (95% CI, 1.3-3.5), 1.7 (95% CI, 1.0-2.9), 1.6 (95% CI, 1.0-2.7),
and 1.2 (95% CI, 0.7-2.1), respectively. Insecticide exposures early in life
appear to be more significant than later exposures, and the highest risk was
observed for exposure during pregnancy. Additionally, more frequent exposure to
insecticides was associated with a higher risk. In contrast to insecticides, the
association between herbicides and leukemia was weak and nonsignificant.
Pesticides were also grouped based on where they were applied. Exposure to
indoor pesticides was associated with an increased risk, whereas no significant
association was observed for exposure to outdoor pesticides. The findings
suggest that exposure to household pesticides is associated with an elevated
risk of childhood leukemia and further indicate the importance of the timing and
location of exposure. Key words: case-control studies, child, herbicides,
insecticides, leukemia, pesticides. Environ Health Perspect 110:955-960 (2002).
[Online 14 August 2002]
http://ehpnet1.niehs.nih.gov/docs/2002/110p955-960ma/ abstract.html
Address correspondence to X. Ma, School of Public Health, University of
California, Berkeley, CA 94720-7360 USA. Telephone: (510) 643-3958. Fax: (510)
643-1735. E-mail:
xmma@uclink4.berkeley.edu
We thank J. Feusner, K. Matthay, S. Month, V. Crouse, K. Leung, and V. Kiley for
assistance with recruiting patients and M. Does for supervising fieldwork.
The study was supported by grants from the National Institute of Environmental
Health Sciences (PS42 ES04705 and RO1 ES09137). X.M. was supported by a grant
from the Centers for Disease Control and Prevention (T01/CCT917644-01).
Received 14 November 2001; accepted 12 March 2002.
You can read this entire article in HTML or PDF.