HOUSEHOLD PESTICIDES AND RISK OF PEDIATRIC BRAIN-TUMORS

A follow-up to a population-based case-control study of pediatric brai n rumors in Los Angeles County, California, involving mothers of 224 c ases and 218 controls, investigated the risk of household pesticide us e from pregnancy to diagnosis. Risk was significantly elevated for pre natal exposure to flea/tick pesticides [odds ratio (OR) = 1.7; 95% con fidence interval (CI), 1.1-2.6], particularly among subjects less than 5 years old at diagnosis (OR = 2.5; CI, 1.2-5.5). Prenatal risk was h ighest for mothers who prepared, applied, or cleaned up flea/tick prod ucts themselves (OR = 2.2; CI, 1.1-4.2; for subjects <5 years of age, OR = 5.4; CI, 1.3-22.3). A significant trend of increased risk with in creased exposure was observed for number of pets treated (p = 0.04). M ultivariate analysis of types of flea/tick products indicated that spr ays/foggers were the only products significantly related to risk (OR = 10.8; CI, 1.3-89.1). Elevated risks were not observed for termite or lice treatments, pesticides for nuisance pests, or yard and garden ins ecticides, herbicides, fungicides, or snail killer. Certain precaution s, if ignored, were associated with significant increased risk: evacua ting the house after spraying or dusting for pests (OR = 1.6; CI, 1.0- 2.6), delaying the harvest of food after pesticide treatment (OR = 3.6 ; CI, 1.0-13.7), and following instructions on pesticide labels (OR = 3.7; CI, 1.5-9.6). These findings indicate that chemicals used in flea /tick products may increase risk of pediatric brain tumors and suggest that further research be done to pinpoint specific chemicals involved .