| Correlating Agricultural Use of Organophosphates with Outdoor Air Concentrations: A Particular Concern for Children Martha Harnly,1 Robert McLaughlin,1 Asa Bradman,2 Meredith Anderson,3 and Robert Gunier1 1California Department of Health Services, Oakland, California, USA; 2University of California, Berkeley, California, USA; 3Impact Assessment Inc., Oakland, California, USA Abstract
For the organophosphate pesticide chlorpyrifos, median inhalation noncancer, acute children's exposures in agricultural communities are elevated above reference doses ; for diazinon, similar exposures are nearly elevated. We used multivariate linear regression analysis to examine the temporal and spatial associations between agricultural use and measured air concentrations of chlorpyrifos, chlorpyrifos oxon, diazinon, and malathion. Agricultural use within a 3-mile radius on the monitoring day and use on the 2-4 prior days were significantly associated with air concentrations (p < 0.01) for all analytes except malathion ; chlorpyrifos oxon showed the strongest association (p < 0.0001) . In the final models, which included weather parameters, the proportion of variance (r2, adjusted for the number of model variables) for all analytes ranged from 0.28 (p < 0.01) for malathion to 0.65 (p < 0.0001) for diazinon. Recent cellular, animal, and human evidence of toxicity, particularly in newborns, supports the public health concern indicated by initial risk estimates. Agricultural applications of organophosphates and their oxon products may have substantial volatization and off-field movement and are a probable source of exposures of public health concern. Key words: agriculture, air, chlorpyrifos, chlorpyrifos oxon, diazinon, inhalation exposure, malathion, organophosphates, pesticides, volatilization. Environ Health Perspect 113:1184-1189 (2005) . doi:10.1289/ehp.7493 available via http://dx.doi.org/ [Online 13 May 2005]
Address correspondence to M. Harnly, California Department of Health Services (CDHS) , Environmental Health Investigations Branch, 1515 Clay St., Suite 1700, Oakland, CA 94612 USA. Telephone: (510) 622-4484. Fax: (510) 622-4505. E-mail: mharnly@dhs.ca.gov We thank S. Lee, P. Reynolds, and M. Lipsett of CDHS, and B. Eskenazi for their technical assistance. This research was supported by U.S. Environmental Protection Agency Science to Achieve Results program grant R826709 and National Institute of Environmental Health Sciences grant 5P01 ES09605-04. This research was not subjected to federal peer review. Opinions are those of the authors and do not necessarily reflect the official position of the CDHS or the funding agencies. No official endorsement should be inferred. The authors declare they have no competing financial interests. Received 16 August 2004 ; accepted 5 May 2005.
The full version of this article is available for free in HTML or PDF formats. |
