title: Farm-related exposures and childhood brain tumours in seven countries: results from the SEARCH International Brain Tumour Study.
abstract: A total of 1218 cases of childhood brain tumours (CBT) and 2223 control subjects from the general population were included in a population-based case-control study conducted in nine centres in seven countries. Mothers were asked about farm- or agriculture-related exposures. Significantly elevated odds ratios (OR) for CBT were associated with children's personal and maternal prenatal exposure while living on a farm with pigs (child OR = 1.7, mother OR = 2.3), horses (child OR = 1.6, mother OR = 1.8), dogs (child OR = 1.5, mother OR = 1.5) and cats (child OR = 1.5, mother OR = 1.7). Children who were exposed to pigs, horses and cats combined, while living on a farm, had a threefold elevated OR for CBT. Increased ORs for primitive neuroectodermal tumours (PNET) were associated with children's farm exposure to dogs (OR = 1.9) and cats (OR = 2.2), and maternal farm exposure to pigs (OR = 4.2). The OR for CBT was elevated (OR = 2.3) for children of mothers who had preconception/prenatal farm- or agriculture-related employment involving potential contact with animals, relative to no farm- or agriculture-related employment. In particular, increased ORs for CBT were observed for children of mothers who were employed as general farmers (OR = 4.1) or general farm workers (OR = 3.8). During the 5 years preceding the index child's birth, maternal exposures were related to CBT, relative to no maternal exposure to agricultural chemicals or animal products: fertilisers (OR = 1.8), pesticides (OR = 2.0), animal manure (OR = 2.0) and unprocessed wool (OR = 3.0). Our findings suggest that various farm-related exposures are positively associated with CBT and warrant further investigation into the public health importance of these associations.
authors.affiliation: Department of Epidemiology and Biostatistics, University of California, San Francisco, California 94118, USA.
authors.forename: Jimmy T
authors.initials: JT
authors.lastname: Efird
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Holly
authors.forename: Susan
authors.initials: S
authors.lastname: Preston-Martin
authors.forename: Beth A
authors.initials: BA
authors.lastname: Mueller
authors.forename: Flora
authors.initials: F
authors.lastname: Lubin
authors.forename: G
authors.initials: G
authors.lastname: Filippini
authors.forename: Rafael
authors.initials: R
authors.lastname: Peris-Bonet
authors.forename: Margaret
authors.initials: M
authors.lastname: McCredie
authors.forename: Sylvaine
authors.initials: S
authors.lastname: Cordier
authors.forename: Annie
authors.initials: A
authors.lastname: Arslan
authors.forename: Paige M
authors.initials: PM
authors.lastname: Bracci
mesh_terms: D000293:Adolescent; D000328:Adult; D000383:Agriculture; D016573:Agrochemicals / Q000009:adverse effects; D000818:Animals; D000829:Animals, Domestic / Q000821:virology; D001932:Brain Neoplasms / Q000209:etiology*; D016022:Case-Control Studies; D002415:Cats; D002417:Cattle; D002648:Child; D002675:Child, Preschool; D004285:Dogs; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006736:Horses; D006801:Humans; D008297:Male; D018242:Neuroectodermal Tumors, Primitive / Q000209:etiology; D016017:Odds Ratio; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D013552:Swine
chemical_list: D016573:Agrochemicals