Carbaryl, Carbofuran, and Methomyl - National Marine Fisheries ...

Table 73. Predicted AChE inhibition and mortality from estimated and measured exposure to
carbaryl, carbofuran, and methomyl.
Concentration (µg/L) % AChE Inhibition % Mortality
Modeling: PRZM-EXAMS 60-day averages 1 (from Table 49)
Carbaryl 12 8.34 0.00
Carbofuran 19 25.39 0.04
Methomyl 81 28.33 0.09
Additive response 44.30 1.38
Modeling: GENEEC 90-day averages (from Table 50)
Sweet Corn
Carbaryl 229 60.67 42.10
Carbofuran 53 47.67 1.63
Methomyl 49 19.61 0.01
Additive response 72.24 73.62
Potatoes
Carbaryl 101 41.28 3.59
Carbofuran 106 63.93 17.02
Methomyl 34 14.66 0.00
Additive response 71.95 59.44
Citrus
Carbaryl 280 65.25 60.14
Methomyl 21 9.76 0.00
Additive response 66.25 62.97
Monitoring: NAWQA maxima in 4 states (from Table 54)
Carbaryl 33.5 19.59 0.07
Carbofuran 32.2 36.02 0.27
Methomyl 0.82 0.48 0.00
Additive response 44.22 1.79
Monitoring: California CDPR database maxima (from Table 55)
Carbaryl 8.4 6.07 0.00
Carbofuran 5.2 8.93 0.00
Methomyl 5.4 2.85 0.00
Additive response 15.58 0.01
Monitoring: Washington EIM database maxima (from Table 56)
Carbaryl 10 7.09 0.00
Carbofuran 2.3 4.29 0.00
Methomyl 0.17 0.11 0.00
Additive response 10.60 0.00
1
PRZM-EXAMS estimates for carbaryl in California peaches (2 applications at 7 lb a.i./acre), carbofuran in
California artichokes (1 application at 2 lb a.i./acre), and methomyl in lettuce (10 applications at 0.9 lb
a.i./acre). Although current labeling may not be consistent for these uses (peaches, artichokes, and
lettuce), the use rate and number of applications are consistent with other labeled uses within the action
area.
The GENEEC estimates are 90 d, time-weighted averages that were based on labeled uses of the
three compounds in sweet corn, potatoes, and citrus. We found no restrictions that would
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