Host factors and genetic susceptibility: a paradigm of the conundrum of pesticide exposure and cancer associations.

Millions of people are exposed to pesticides in non-trivial ways though their work, their leisure and their home environment. Women and children are understudied populations. The mode and types of pesticides to which women and children are exposed are often different from exposures experienced by men. A relatively small proportion of exposed individuals develop the uncommon cancers that have been associated with exposure to specific pesticides. Host factors, including such variables as gender, age at exposure, previous personal and family history, medical history, and genetic susceptibility have been implicated as explanations. The challenges of designing and implementing studies of pesticide exposure and cancer are examined with a special focus on the complexities of studying the environmental and occupational exposure of women to pesticides of varying toxicity using gender-appropriate methodology.