Median chlorpyrifos and diazinon dust concentrations in samples from farmworker homes in the city of Salinas, CA by year of collection and kilograms applied (trendline) at the county-level (Monterey County) for agricultural purposes from 1999-2007. † In December 2001 and 2002, residential products containing chlorpyrifos and diazinon, respectively were canceled. ‡Technical registrants were to buy back existing products from retailers by the end of December 2004. * Indicates that study had significantly higher dust concentrations compared to those observed in farmworker homes sampled in the present study (Wilcoxon Mann-Whitney tests, p < 0.05). ** CHAMACOS refers to the C enter for the H ealth A ssessment of M others a nd C hildren o f S alinas longitudinal birth cohort study (Harnly et al. 2009).