Lu et al. CPES-WA and CPES-GA children, respec- tively. Notably, we detected 11 OP and 3 pyre- throid insecticides in children’s food samples; levels ranged from 1 to 387 ng/g for OP and 2 to 1,133 ng/g for pyrethroid insecticides. In general, the pesticide residues that we measured in CPES were within the ranges reported by the national PDP in 2004 (for comparison with CPES-WA samples col- lected in 2004) and 2006 (for comparison with CPES-GA samples collected in 2006) (Table 5). However, there were some excep- tions. Several food samples collected from CPES-WA children contained higher residue levels than reported by the PDP, including a) a composite sample of cherries, a nectar- ine, and an apple with 387 ng/g phosmet and 1 ng/g chlorpyrifos; b) a nectarine with 252 ng/g phosmet; c) a composite sample of raspberries, blueberries, blackberries, baby carrots, and a peach with 4, 7, and 45 ng/g malathion, phosmet, and azinphos-methyl, respectively; d) an apple with 111 ng/g azin- phos-methyl; and e) a composite sample of lettuce, broccoli, and mushroom with 1,133 ng/g cypermethrin. In addition, two strawberry samples in the CPES-WA MBA (Table 6) contained 363 ng/g chlorpyrifos and 93 ng/g bifenthrin. Several food samples col- lected from CPES-GA children also contained higher residue levels than reported by the PDP (Table 5), including a) a composite sample of strawberries and spinach with 921 ng/g per- methrin; b) a composite sample of potato, yellow bell pepper, broccoli, and ketchup with 10 ng/g chlorpyrifos, 9 ng/g methamidophos, 90 ng/g acephate; and 8 ng/g cypermethrin; and c) a celery sample with 78 ng/g methami- dophos and 350 ng/g acephate. In addition, an apple sample provided by a CPES-WA child contained 111 ng/g azinphos-methyl, which exceeded the highest azinphos-methyl concen- tration reported by the PDP in 2004 (in pears, 42 ng/g). Similarly, a composite food sample with lettuce, broccoli, and mushroom con- tained cypermethrin levels that exceeded the highest levels reported by the PDP in 2004 (in lettuce and canned spinach, 90 ng/g). An MBA sample of strawberries contained 363 ng/g chlorpyrifos, which is close to the highest level that PDP reported in 2004 (in bell peppers, 470 ng/g). Commodities such as apples, bell peppers, celery, cherries, green beans, peaches, spinach, and strawberries that are frequently consumed by CPES children were often found by the PDP to have OP and pyrethroid pesticides in both 2004 and 2006 (Tables 1 and 5). Discussion Characterizing dietary pesticide exposures, par- ticularly for infants and children, has become an essential component of cumulative pesti- cide risk assessment, as mandated by the 1996 FQPA. Several reports (Lu et al. 2006a, 2006b, 2008, 2009; Schettgen et al. 2002) have clearly demonstrated the significant con- tribution of dietary intakes to the overall OP and pyrethroid pesticide exposure in children and highlighted the critical need to quantify the health risks associated with the low but chronic daily exposures to those pesticides. As the result of the 1993 NRC report, the U.S. Congress funded the PDP under the USDA to test pesticide residues annually in foods consumed most often by children and, to the extent possible, “as eaten.” Since its inception, PDP has tested > 200,000 food commod- ity samples for an extensive list of pesticides. When pesticide residues reported in the PDP database are combined with food consump- tion information, such as those surveyed in the Continuing Survey of Food Intakes by Individuals [now integrated in the National Health and Nutrition Examination Survey (NHANES) conducted by the Centers for Disease Control and Prevention] or the Total Diet Study conducted by the FDA (Egan et al. 2007), mathematical model simulations can be used to provide a basis for estimating pesticide dietary exposures and risks. In theory, those estimated pesticide intakes would reflect dietary exposures at the population level; however, it is often the consumption of so-called high-risk food commodities containing elevated pesticide residues that shapes the outcome of dietary risk assessment. Therefore, it is imperative to meas- ure pesticide residues in foods actually con- sumed by children as part of their customary diets. Direct measures remove many of the unknowns and assumptions that must be made when calculating dietary risk assessments from separately collected consumption surveys and pesticide residue databases. Before further interpreting the results obtained from the CPES, the limitations of this study should be acknowledged. First of all, many of the 24-hr duplicate food sam- ples that we analyzed were composite food samples, so it is not possible to link pesticide residues found in the composite samples to individual food commodities. Second, the reported pesticide residues for those com- posite food samples may be underestimated because of the nature of compositing multiple food items into one sample. It is likely that we combined foods containing no pesticide resi- dues with foods with pesticide residues, result- ing in a diluted composite sample. Third, the 24-hr duplicate food samples collected from Table 5. Comparison of pesticides, residue levels, and commodities reported in CPES and PDP. Detected concentration range (ng/g) and sample containing the highest pesticide level Pesticidea Acephate Azinphos methyl Bifenthrin Chlorpyrifos Cypermethrin Dimethoate Esfenvalerate Ethion Malathion Methamidophos Omethoate Permethrin Phosalone Phosmet 1628 CPES-WA Celery, onion, and corn (1–18)b Apple (8–111) Strawberries, green beans, raspberries, and blueberries (93–149)b Strawberries (1–363)c PDP 2004 Green beans (2–2,000) Pear (13–42) Strawberries (5–300) Bell peppers (1–470)c Lettuce, broccoli, and mushrooms Lettuce and canned spinach Spinach, tomato, spaghetti sauce Peach, apple sauce, pineapple, pea pod, Bell pepper (3–35) (1,133)b and corn (6–10)b Cherries (71)d Orange juice (4–24) Cantaloupe (4–11) Juice box (1)d and corn (12)b,d Peach, apple sauce, pineapple, pea pod, Spinach and cauliflower (90)b,d ND Cherries, nectarine, and apple (9–387)b (25–90) ND ND Lettuce (1–5,000) Green beans (2–560) Lettuce and bell pepper (4–97) Canned spinach (48–11,000) Apple (10–57) Pear (3–1,600) CPES-GA Strawberries, blueberries, and grape Potato, bell pepper, broccoli, and Celery (39–350) ND juice (2–28)b ketchup (2–10)b (8–18)b ND ND ND ND ND Celery (9–78) Spinach and strawberries (4–921)b Carrots and baby green lettuce (29–84)b Peach (25–86) PDP 2006 Green beans (3–2,100) Peach (2–620) Green beans (5–180) Collard greens (2–6,300)c Collard greens (50–5,000) Green beans (2–1,600) Tomato (14–120) ND Celery (3–610) Green beans (2–500) Kale greens (4–220) Kale greens (62–8,400) ND Peach (5–2,200) ND, not determined. CPES-WA data included samples from the MBA. PDP 2004 data are from USDA (2004). PDP 2006 data are from USDA (2006). aEntries in italics are pyrethrins; all other entries are OP pesticide. bSamples were composite food samples. cPesticide concentration exceeded the EPA tolerance level: 50 ppb chlor- pyrifos (U.S. EPA 1996). dOnly one sample analyzed. ovlume 118 | number 11 | November 2010 • Environmental Health Perspectives