Table 5.
Summary statistics on the estimated intake and hazard quotients (HQ) for all study children.a
| Select Summary Statistics for HQs based on 54 dust samples from farmworker and urban children |
||||||||
|---|---|---|---|---|---|---|---|---|
| Analyte | RfD (mg/kg/dy)b |
# samples with concentration >LOD |
Range of Intake (mg/kg/day)c |
p50 | p75 | p95 | Max | |
| Organophosphates | Min | Max | ||||||
| diazinon | 0.0002 | 36 | -- | 7.0 × 10-07 | 2.5 × 10-04 | 4.3 × 10-04 | 1.6 × 10-03 | 3.5 × 10-03 |
| chlorpyrifos | 0.00003 | 25 | -- | 1.1 ×10-06 | -- | 4.9 × 10-03 | 2.3 × 10-02 | 3.8 × 10-02 |
| malathion | 0.07 | 5 | -- | 4.9 × 10-06 | -- | -- | 2.8 × 10-06 | 7.0 × 10-05 |
| tetrachlorvinphos | 0.04 | 4 | -- | 1.5 × 10-06 | -- | -- | 2.2 × 10-05 | 3.9 × 10-05 |
| Pyrethroids | ||||||||
| cis-permethrind | 0.25 | 54 | 5.4 × 10-08 | 1.3 × 10-04 | 9.7 × 10-06 | 2.0 × 10-05 | 8.4 × 10-05 | 5.1 × 10-04 |
| trans-permethrind | 0.25 | 54 | 8.6 × 10-08 | 2.2 × 10-04 | 1.7 × 10-05 | 3.2 × 10-05 | 1.6 × 10-04 | 8.9 × 10-04 |
| cypermethrin | 0.06 | 32 | -- | 6.4 × 10-05 | 2.5 ×10-05 | 8.4 × 10-05 | 4.8 × 10-04 | 1.1 × 10-03 |
| bifenthrin | 0.015 | 15 | -- | 1.1 × 10-05 | -- | 4.4 × 10-06 | 2.6 × 10-05 | 7.5 × 10-04 |
| sumithrin | 0.0007 | 9 | -- | 3.7 × 10-06 | -- | -- | 3.2 × 10-03 | 5.2 × 10-03 |
| deltamethrin | 0.0033 | 8 | -- | 9.0 × 10-05 | -- | -- | 6.7 × 10-03 | 2.7 × 10-02 |
| prallethrin | 0.025 | 1 | -- | 1.9 × 10-07 | -- | -- | -- | 7.4 × 10-06 |
| esfenvalerate | 0.02 | 1 | -- | 4.4 × 10-07 | -- | -- | -- | 2.2 × 10-05 |
| Others | ||||||||
| chlorthal-dimethyl | 0.01 | 28 | -- | 1.8 × 10-07 | 3.0 × 10-06 | 7.2 × 10-06 | 1.5 × 10-05 | 1.8 × 10-05 |
| piperonyl butoxide | 0.16 | 49 | -- | 2.2 × 10-04 | 5.0 × 10-06 | 1.7 × 10-05 | 2.5 × 10-04 | 1.4 × 10-03 |
a. A hazard quotient (HQ) was calculated as the ratio of the potential dust intake to the respective analyte reference dose (RfD). The HQ was only calculated for those analytes for which an RfD was available. b. Chronic population adjusted doses (cPADs) were used as the reference dose for chlorpyrifos (cPAD for children and females 13-50 years of age) and deltamethrin. Sources: IRIS database http://cfpub.epa.gov/ncea/iris/index.cfm?fuseaction=iris.showSubstanceList and EPA's Pesticide Registration Status: http://www.epa.gov/opp00001/reregistration/status.htm. c. Intake was calculated by multiplying the toxicant dust concentration by an ingestion rate of 0.10 g/day (100 mg/day) then dividing by the child-specific body weight (kg). d. The RfD available for "permethrin" was used for each individual isomer in our calculations. Notation: '--' Value is not reported since dust concentrations were less than the limit of detection.