B-1

Appendix B

RQ Calculations for Primary Exposure (Consumption of Bait) Scenarios
B-2

Table B-1 Acute Oral RQs for Generic and Passerine Birds Based on Consumption of Bait.

Taxa Weight 

(g)

Food 

intake

(g drywt/day)

Rodenticide 

intake

(mg 

a.i./kgbwt/day)

Unadjusted

LD50

(mg a.i./

kg-bwt)1

Adjusted LD50

(mg a.i./kg-bwt)2

RQ 

(unadjusted)3,4

RQ

(adjusted for 

weight)4,5

Brodifacoum—0.005% a.i. 

Passeriform 

Birds

20 5.1 12.70

0.25

0.65 0.40 50.79* 19.61* 31.56*

100 19.9 9.97 0.44 0.33 39.90* 22.67* 30.07*

1000 141.2 7.06 0.25 0.25 28.24* 27.89* 28.07*

Generic 

Birds

20 4.6 11.39 0.65 0.40 45.56* 17.59* 28.31*

100 13.0 6.49 0.44 0.33 25.98* 14.76* 19.58*

1000 58.2 2.91 0.25 0.25 11.63* 11.48* 11.56*

Difethialone—0.0025% 

Passeriform 

Birds

20 5.1 6.35

0.3

0.21 21.16* 29.80*

100 19.9 4.99 0.27 16.62* 18.39*

1000 141.2 3.53 0.38 11.77* 9.22*

Generic 

Birds

20 4.6 5.69 0.21 18.98* 26.73*

100 13.0 3.25 0.27 10.82* 11.97*

1000 58.2 1.45 0.38 4.85* 3.80*

Warfarin—0.025% a.i.

Passeriform 

Birds

20 5.1 63.49

540

272.6 0.12 0.23

100 19.9 49.87 347.0 0.10 0.14

1000 141.2 35.30 490.2 0.07 0.07

Generic 

Birds

20 4.6 56.95 272.6 0.11 0.21

100 13.0 32.47 347.0 0.06 0.09

1000 58.2 14.54 490.2 0.03 0.03

Warfarin—0.054% a.i. 

Passeriform 

Birds

20 5.1 137.13

540

272.6 0.26 0.50*

100 19.9 107.72 347.0 0.21 0.31

1000 141.2 76.26 490.2 0.15 0.16

Generic 

Birds

20 4.6 123.00 272.6 0.23 0.45

100 13.0 70.14 347.0 0.34 0.20

1000 58.2 31.40 490.2 0.06 0.06

Chlorophacinone--0.005% a.i. 

Passeriform 

Birds

20 5.1 12.70

258

182.4 8943.6 0.05 0.07 <0.01

100 19.9 9.97 232.2 762.2 0.04 0.04 0.01

1000 141.2 7.06 327.9 22.5 0.03 0.02 0.32

Generic 

Birds

20 4.6 11.39 182.4 8943.6 0.04 0.06 <0.01

100 13.0 6.49 232.2 762.2 0.03 0.03 0.01

1000 58.2 2.91 327.9 22.5 0.01 0.01 0.13

Diphacinone—0.005% a.i.

Passeriform 

Birds

20 5.1 12.70

1630

1163 0.01 0.01

100 19.9 9.97 1480 0.01 0.01

1000 141.2 7.06 2091 <0.01 <0.01

Generic 

Birds

20 4.6 11.39 1163 0.01 0.01

100 13.0 6.49 1480 <0.01 <0.01

1000 58.2 2.91 2091 <0.01 <0.01

Bromethalin—0.01%

Passeriform 20 5.1 25.39 4.6 3.27 5.52* 7.76*
B-3

Table B-1 Acute Oral RQs for Generic and Passerine Birds Based on Consumption of Bait.

Taxa Weight 

(g)

Food 

intake

(g drywt/day)

Rodenticide 

intake

(mg 

a.i./kgbwt/day)

Unadjusted

LD50

(mg a.i./

kg-bwt)1

Adjusted LD50

(mg a.i./kg-bwt)2

RQ 

(unadjusted)3,4

RQ

(adjusted for 

weight)4,5

Birds 100 19.9 19.95 4.16 4.34* 4.79*

1000 141.2 14.12 5.88 3.07* 2.40*

Generic 

Birds

20 4.6 22.78 3.27 4.95* 6.96*

100 13.0 12.99 4.16 2.82* 3.12*

1000 58.2 5.82 5.88 1.26* 0.99* 1

LD50 from most sensitive mallard duck or northern bobwhite quail acute oral study. 2

Split columns show LD50s adjusted using different scaling factors. For brodifacoum, the left and right columns give 

the adjusted LD50 using brodifacoum specific scaling factor from Mineau et al. (1996) and (2001), respectively. For 

chlorophacinone, the left and right columns gives the adjusted LD50 using the EFED default scaling factor from 

Mineau et al. (1996) and the chlorophacinone specific scaling factor from Mineau et al. (2001), respectively. For 

other chemicals, the single column gives the adjusted LD50 using the EFED default scaling factor from Mineau et al. 

(1996).

3 RQ calculated as daily rodenticide intake / LD50. 4

 * RQ exceeds Acute Risk LOC. 5 Split columns show RQs calculated from the respective adjusted LD50, see footnote #2.
B-4

Table B-2 Generic and Passerine Birds: Time to consume an LD50-dose of Bait and grams of bait needed to reach the 

LD50-dose.

Taxa Weight 

(g)

Unadjusted

LD50

(mg a.i./ kgbwt)1

Adjusted LD50

(mg a.i./kg-bwt)2

Days to 

consume an 

unadjusted 

LD50-dose of 

bait

Days to consume an 

adjusted LD50-dose of 

bait3

Grams of 

bait to 

consume an 

unadjusted 

LD50-dose

Grams of bait to 

consume an 

adjusted LD50-

dose4

Brodifacoum—0.005% 

Passeriform 

Birds

20

0.25

0.65 0.40 <1 <1 <1 0.1 0.3 0.3

100 0.44 0.33 <1 <1 <1 0.5 0.9 0.9

1000 0.25 0.25 <1 <1 <1 5 5 5

Generic 

Birds

20 0.65 0.40 <1 <1 <1 0.1 0.3 0.2

100 0.44 0.33 <1 <1 <1 0.5 0.9 0.7

1000 0.25 0.25 <1 <1 <1 5 5 5

Difethialone—0.0025%

Passeriform 

Birds

20

0.30

0.21 <1 <1 0.2 0.2

100 0.27 <1 <1 1.2 1.1

1000 0.38 <1 <1 12 15

Generic 

Birds

20 0.21 <1 <1 0.2 0.2

100 0.27 <1 <1 1.2 1.1

1000 0.38 <1 <1 12 15

Warfarin—0.025% a.i.

Passeriform 

Birds

20

525

272.6 8-9 4-5 46 25

100 347.0 11-12 7-8 239 160

1000 490.2 16-17 14-15 2400 2100

Generic 

Birds

20 272.6 9-10 4-5 46 23

100 347.0 18-19 11-12 247 156

1000 490.2 46-47 41-42 2733 2442

Warfarin—0.054% a.i.

Passeriform 

Birds

20

525

272.6 3-4 1-2 20 10

100 347.0 4-5 3-4 80 80

1000 490.2 7-8 6-7 140 990

Generic 

Birds

20 272.6 4-5 2-3 23 14

100 347.0 7-8 5-6 104 78

1000 490.2 18-19 16-17 1105 989

Chlorophacinone--0.005% a.i.

Passeriform 20 258 182.4 8876 25-26 16-17 >365 132 86 >1800
B-5

Table B-2 Generic and Passerine Birds: Time to consume an LD50-dose of Bait and grams of bait needed to reach the 

LD50-dose.

Taxa Weight 

(g)

Unadjusted

LD50

(mg a.i./ kgbwt)1

Adjusted LD50

(mg a.i./kg-bwt)2

Days to 

consume an 

unadjusted 

LD50-dose of 

bait

Days to consume an 

adjusted LD50-dose of 

bait3

Grams of 

bait to 

consume an 

unadjusted 

LD50-dose

Grams of bait to 

consume an 

adjusted LD50-

dose4

Birds 100 232.2 757 35-36 30-31 >365 718 620 >7300

1000 327.9 22.3 62-63 117-118 3-4 8897 17000 565

Generic 

Birds

20 182.4 8944 29-30 18-19 >365 136 87 >1663

100 232.2 757 75-76 60-61 >365 987 792 >4741

1000 327.9 22.3 >365 >365 8-9 >21200 >21200 523

Diphacinone—0.005% a.i.

Passeriform 

Birds

20

1630

1167 >365 >365 >1800 >1800

100 1485 >365 >365 >7300 >7300

1000 2098 >365 >365 >52000 >52000

Generic 

Birds

20 1167 >365 >365 >1660 >1660

100 1485 >365 >365 >4740 >4740

1000 2098 >365 >365 >21200 >21200

Bromethalin—0.01%

Passeriform 

Birds

20

4.6

3.27 <1 <1 0.9 0.7

100 4.16 <1 <1 4.6 4.2

1000 5.88 <1 <1 46 59

Generic 

Birds

20 3.27 <1 <1 0.9 0.7

100 4.16 <1 <1 4.6 4.2

1000 5.88 <1 <1 46 59 1

LD50 from most sensitive mallard duck or northern bobwhite quail acute oral study. 2

Split columns show LD50s adjusted using different scaling factors. For brodifacoum, the left and right columns give the adjusted LD50 using 

brodifacoum specific scaling factor from Mineau et al. (1996) and (2001), respectively. For chlorophacinone, the left and right columns gives the 

adjusted LD50 using the EFED default scaling factor from Mineau et al. (1996) and the chlorophacinone specific scaling factor from Mineau et al. 

(2001), respectively. For other chemicals, the single column gives the adjusted LD50 using the EFED default scaling factor from Mineau et al. (1996). 3

Split columns show days to consume sufficient bait to reach the LD50 calculated from the respective adjusted LD50, see footnote #2. 4

Split columns show bait (g) to consume to reach the LD50 calculated from the respective adjusted LD50, see footnote #2.
B-6

Table B-3 Acute Oral RQs for Passerine and Generic Birds Based on Consumption of 

Bait accumulated over a six day feeding exposure.

Taxa Weight 

(g)

Rodenticide 

six-day 

accumulati

on (mg 

a.i./kg-bwt)

LD50

(mg 

a.i./kg

-bwt)1

Adjusted LD50

(mg a.i./kg-bwt)2

RQ based 

on 

unadjusted 

LD50

3,4

RQ (adjusted for 

weight)4,5

Brodifacoum—0.005% a.i.

Passeriform 

Birds

20 76

0.25

0.65 0.40 303* 117* 188*

100 60 0.44 0.33 238* 135* 179*

1000 42 0.25 0.25 169* 166* 167*

Generic 

Birds

20 68 0.65 0.40 272* 105* 169*

100 39 0.44 0.33 155* 88* 117*

1000 17 0.25 0.25 69* 69* 69*

Difethialone—0.0025%

Passeriform 

Birds

20 36

0.3

0.21 119* 168*

100 28 0.27 94* 104*

1000 20 0.38 66* 52*

Generic 

Birds

20 32 0.21 107* 151*

100 18 0.27 61* 68*

1000 8 0.38 27* 21*

Warfarin—0.025% a.i.

Passeriform 

Birds

20 371

540

272.6 0.71* 1.36*

100 292 347.0 0.56* 0.84*

1000 206 490.2 0.39 0.42

Generic 

Birds

20 333 272.6 0.63* 1.22*

100 190 347.0 0.36 0.55*

1000 85 490.2 0.16 0.17

Warfarin—0.054% a.i.

Passeriform 

Birds

20 802

540

272.6 1.53* 2.94*

100 630 347.0 1.20* 1.81*

1000 446 490.2 0.85* 0.91*

Generic 

Birds

20 719 272.6 1.37* 2.64*

100 410 347.0 0.78* 1.18*

1000 184 490.2 0.45 0.37

Chlorophacinone--0.005% a.i.

Passeriform 

Birds

20 73

50

182.4 8943.6 0.28 0.40 0.01

100 57 232.2 762.2 0.22 0.25 0.08

1000 40 327.9 22.5 0.16 0.12 1.81*

Generic 

Birds

20 65 182.4 8943.6 0.25 0.36 0.01

100 37 232.2 762.2 0.14 0.16 0.05

1000 17 327.9 22.5 0.06 0.05 0.74*

Diphacinone—0.005% a.i.

Passeriform 

Birds

20 56

1630

1163 0.03 0.05

100 44 1480 0.03 0.03

1000 31 2091 0.02 0.01

Generic 

Birds

20 50 1163 0.03 0.04

100 29 1480 0.02 0.02

1000 13 2091 0.01 0.01

Bromethalin—0.01%

Passeriform 

Birds

20 112 4.6 3.27 NA6 NA

100 88 4.16 NA NA
B-7

Table B-3 Acute Oral RQs for Passerine and Generic Birds Based on Consumption of 

Bait accumulated over a six day feeding exposure.

Taxa Weight 

(g)

Rodenticide 

six-day 

accumulati

on (mg 

a.i./kg-bwt)

LD50

(mg 

a.i./kg

-bwt)1

Adjusted LD50

(mg a.i./kg-bwt)2

RQ based 

on 

unadjusted 

LD50

3,4

RQ (adjusted for 

weight)4,5

1000 62 5.88 NA NA

Generic 

Birds

20 101 3.27 NA NA

100 57 4.16 NA NA

1000 26 5.88 NA NA 1

LD50 from most sensitive mallard duck or northern bobwhite quail acute oral study. 2

Split columns show LD50s adjusted using different scaling factors. For brodifacoum, the left and right columns 

give the adjusted LD50 using brodifacoum specific scaling factor from Mineau et al. (1996) and (2001), 

respectively. For chlorophacinone, the left and right columns gives the adjusted LD50 using the EFED default 

scaling factor from Mineau et al. (1996) and the chlorophacinone specific scaling factor from Mineau et al. 

(2001), respectively. For other chemicals, the single column gives the adjusted LD50 using the EFED default 

scaling factor from Mineau et al. (1996).

3 RQ calculated as 60-day accumulated body burden / LD50. 4

 * RQ exceeds Acute Risk LOC. 5 Split columns show RQs calculated from the respective adjusted LD50, see footnote #2. 6 NA- not applicable. Animals consuming bromethalin are not expected to continue feeding on bromethalin bait 

for six days.
B-8

Table B-4 Acute Oral RQs for Generic and Rodent Mammals Based on Consumption of 

Bait.

Taxa Weight 

(g)

Food 

intake

(g drywt/day)

Rodenticide 

intake

(mg a.i./kgbwt/day)

LD50

(mg 

a.i./kgbwt)1

Adjusted 

LD50 (mg 

a.i./kg-bwt)2

RQ (unadjusted)3,4

RQ 

(adjusted for 

weight)3,4

Brodifacoum—0.005% a.i.

Rodent 

Mammals

15 2.9 9.53

0.48

0.96 19.86* 9.93*

35 4.6 6.59 0.78 13.73* 8.48*

1000 30.6 1.53 0.34 3.18* 4.55*

Generic 

Mammals

15 2.2 7.26 0.96 15.12* 7.56*

35 4.4 6.24 0.78 13.00* 8.03*

1000 68.7 3.44 0.34 7.16* 10.23*

Difethialone—0.0025%

Rodent 

Mammals

15 2.9 4.77

0.56

1.11 8.51* 4.30*

35 4.6 3.29 0.90 5.88* 3.67*

1000 30.6 0.76 0.39 1.36* 1.97*

Generic 

Mammals

15 2.2 3.63 1.11 6.48* 3.27*

35 4.4 3.12 0.90 5.57* 3.48*

1000 68.7 1.72 0.39 3.07* 4.43*

Warfarin—0.025% a.i.

Rodent 

Mammals

15 2.9 47.7

3

5.7 15.89* 8.36*

35 4.6 32.9 4.6 10.98* 7.14*

1000 30.6 7.6 2.0 2.55* 3.83*

Generic 

Mammals

15 2.2 36.3 5.7 12.09* 6.36*

35 4.4 31.2 4.6 10.40* 6.76*

1000 68.7 17.2 2.0 5.73* 8.61*

Warfarin – 0.054% a.i.

Rodent 

Mammals

15 2.9 102.97

3

5.7 34.32* 18.05*

35 4.6 71.17 4.6 23.72* 15.42*

1000 30.6 16.50 2.0 5.50* 8.27*

Generic 

Mammals

15 2.2 78.36 5.7 26.12* 13.74*

35 4.4 67.39 4.6 22.46* 14.60*

1000 68.7 37.11 2.0 12.37* 18.59*

Chlorophacinone--0.005% a.i.

Rodent 

Mammals

15 2.9 9.53

6.26

11.6 1.52* 0.82*

35 4.6 6.59 9.4 1.05* 0.70*

1000 30.6 1.53 4.1 0.24 0.38

Generic 

Mammals

15 2.2 7.26 11.6 1.16* 0.63*

35 4.4 6.24 9.4 1.00* 0.67*

1000 68.7 3.44 4.1 0.55* 0.85*

Diphacinone—0.005% a.i.

Rodent 

Mammals

15 2.9 9.53

2.46

4.8 4.13* 1.97*

35 4.6 6.59 3.9 2.83* 1.68*

1000 30.6 1.53 1.7 0.66* 0.90*

Generic 

Mammals

15 2.2 7.26 4.8 3.14* 1.50*

35 4.4 6.24 3.9 2.70* 1.59*

1000 68.7 3.44 1.7 1.49* 2.03*

Bromethalin—0.01%

Rodent 

Mammals

15 2.9 19.07

2.2

3.7 8.7* 5.1*

35 4.6 13.18 3.0 6.0* 4.4*

1000 30.6 3.06 1.3 1.4* 2.4*
B-9

Table B-4 Acute Oral RQs for Generic and Rodent Mammals Based on Consumption of 

Bait.

Taxa Weight 

(g)

Food 

intake

(g drywt/day)

Rodenticide 

intake

(mg a.i./kgbwt/day)

LD50

(mg 

a.i./kgbwt)1

Adjusted 

LD50 (mg 

a.i./kg-bwt)2

RQ (unadjusted)3,4

RQ 

(adjusted for 

weight)3,4

Generic 

Mammals

15 2.2 14.51 3.7 6.6* 3.9*

35 4.4 12.48 3.0 5.7* 4.1*

1000 68.7 6.87 1.3 3.1* 5.3* 1

LD50 from most sensitive laboratory rat acute oral study. 2 LD50 adjusted using the “body weight 3⁄4” adjustment (USEPA 1995, 2011). 3 RQ calculated as daily rodenticide intake / LD50. 4

 * RQ exceeds Acute Risk LOC.
B-10

Table B-5. Generic and Rodent Mammals: Time to consume an LD50-dose of Bait and grams of bait 

needed to reach the LD50-dose.

Taxa Weight 

(g)

Unadjusted

LD50

(mg a.i./ kgbwt)1

Adjusted 

LD50

(mg a.i./kgbwt)2

Days to 

consume an 

unadjusted 

LD50-dose of 

bait

Days to 

consume an 

adjusted 

LD50-dose of 

bait

Grams of 

bait to 

consume an 

unadjusted 

LD50-dose

Grams of bait 

to consume an 

adjusted 

LD50-dose

Brodifacoum—0.005% a.i.

Rodent 

mammals

15

0.48

0.96 <1 <1 0.1 0.3

35 0.78 <1 <1 0.3 0.5

1000 0.34 <1 <1 9.6 6.7

Generic 

mammals

15 0.96 <1 <1 0.1 0.3

35 0.78 <1 <1 0.3 0.5

1000 0.34 <1 <1 9.6 6.7

Difethialone—0.0025%

Rodent 

mammals

15

0.56

1.11 <1 <1 0.3 0.7

35 0.90 <1 <1 0.8 1.3

1000 0.39 <1 <1 22 16

Generic 

mammals

15 1.11 <1 <1 0.3 0.7

35 0.90 <1 <1 0.8 1.3

1000 0.39 <1 <1 22 16

Warfarin—0.025% a.i.

Rodent 

mammals

15

3.0

5.7 <1 <1 0.2 0.3

35 4.6 <1 <1 0.4 0.7

1000 2.0 <1 <1 12 8.0

Generic 

mammals

15 5.7 <1 <1 0.2 0.3

35 4.6 <1 <1 0.4 0.7

1000 2.0 <1 <1 12 8.0

Warfarin—0.054% a.i.

Rodent 

mammals

15

3.0

5.7 <1 <1 0.1 0.2

35 4.6 <1 <1 0.2 0.3

1000 2.0 <1 <1 5.6 3.7

Generic 

mammals

15 5.7 <1 <1 0.1 0.2

35 4.6 <1 <1 0.2 0.3

1000 2.0 <1 <1 5.6 3.7
B-11

Table B-5. Generic and Rodent Mammals: Time to consume an LD50-dose of Bait and grams of bait 

needed to reach the LD50-dose.

Taxa Weight 

(g)

Unadjusted

LD50

(mg a.i./ kgbwt)1

Adjusted 

LD50

(mg a.i./kgbwt)2

Days to 

consume an 

unadjusted 

LD50-dose of 

bait

Days to 

consume an 

adjusted 

LD50-dose of 

bait

Grams of 

bait to 

consume an 

unadjusted 

LD50-dose

Grams of bait 

to consume an 

adjusted 

LD50-dose

Chlorophacinone--0.005% a.i.

Rodent 

mammals

15

6.26

11.6 <1 1-2 1.9 6

35 9.4 <1 1-2 4.4 9

1000 4.1 1-2 1-2 61 61

Generic 

mammals

15 11.6 <1 <1 1.9 3.5

35 9.4 <1 1-2 4.4 9

1000 4.1 2-3 1-2 206 137

Diphacinone—0.005% a.i.

Rodent 

mammals

15

1.9

3.6 <1 <1 0.6 1.1

35 2.9 <1 <1 1.3 2.1

1000 1.3 <1 <1 38 25

Generic 

mammals

15 3.6 <1 <1 0.6 1.1

35 2.9 <1 <1 1.3 2.1

1000 1.3 <1 <1 38 25

Bromethalin—0.01%

Rodent 

mammals

15

2.2

3.7 <1 <1 0.3 0.6

35 3.0 <1 <1 0.8 1.1

1000 1.3 <1 <1 22 13

Generic 

mammals

15 3.7 <1 <1 0.3 0.6

35 3.0 <1 <1 0.8 1.1

1000 1.3 <1 <1 22 13 1

LD50 from most sensitive laboratory rat acute oral study. 2 LD50 adjusted using the “body weight 3⁄4” adjustment (USEPA 1995, 2011).
B-12

Table B-6. Acute Oral RQs for Rodent and Generic Mammals Based on Consumption of 

Bait accumulated over a six day feeding exposure.

Taxa Weight 

(g)

Rodenticide 

six-day 

accumulation 

(mg a.i./kgbwt)

LD50 (mg 

a.i./kg-bwt)1

Adjusted 

LD50 (mg 

a.i./kgbwt)2

RQ based on 

unadjusted 

LD50

3,4

RQ (adjusted 

for weight)3,4

Brodifacoum—0.005% a.i.

Rodent 

Mammals

15 57

0.48

0.96 119* 59*

35 39 0.78 82* 51*

1000 9 0.34 19* 27*

Generic 

Mammals

15 43 0.96 90* 45*

35 37 0.78 78* 48*

1000 20 0.34 43* 61*

Difethialone—0.0025%

Rodent 

Mammals

15 27

0.56

1.11 48* 24*

35 19 0.90 33* 21*

1000 4 0.39 8* 11*

Generic 

Mammals

15 20 1.11 37* 18*

35 18 0.90 31* 20*

1000 10 0.39 17* 25*

Warfarin—0.025% a.i.

Rodent 

Mammals

15 279

3

5.7 93* 49*

35 193 4.6 64* 42*

1000 45 2.0 15* 22*

Generic 

Mammals

15 212 5.7 71* 37*

35 182 4.6 61* 40*

1000 100 2.0 33* 50*

Warfarin—0.054% a.i.

Rodent 

Mammals

15 602

3

5.7 201* 106*

35 416 4.6 139* 90*

1000 96 2.0 32* 48*

Generic 

Mammals

15 458 5.7 153* 80*

35 394 4.6 131* 85*

1000 217 2.0 72* 109*

Chlorophacinone--0.005% a.i.

Rodent 

Mammals

15 54

6.26

11.6 8.70* 4.68*

35 38 9.4 6.02* 4.00*

1000 9 4.1 1.40* 2.14*

Generic 

Mammals

15 41 11.6 6.62* 3.56*

35 36 9.4 5.70* 3.79*

1000 20 4.1 3.14* 4.82*

Diphacinone—0.005% a.i.

Rodent 

Mammals

15 42

1.9

3.6 22.1* 11.6*

35 29 2.9 15.3* 9.9*

1000 7 1.3 3.5* 5.3*

Generic 

Mammals

15 32 3.6 16.8* 8.8*

35 27 2.9 14.4* 9.3*

1000 15 1.3 8.0* 11.9*

Bromethalin—0.01%

Rodent 

Mammals

15 84 2.2 3.7 NA5 NA

35 58 3.0 NA NA
B-13

Table B-6. Acute Oral RQs for Rodent and Generic Mammals Based on Consumption of 

Bait accumulated over a six day feeding exposure.

Taxa Weight 

(g)

Rodenticide 

six-day 

accumulation 

(mg a.i./kgbwt)

LD50 (mg 

a.i./kg-bwt)1

Adjusted 

LD50 (mg 

a.i./kgbwt)2

RQ based on 

unadjusted 

LD50

3,4

RQ (adjusted 

for weight)3,4

1000 14 1.3 NA NA

Generic 

Mammals

15 64 3.7 NA NA

35 55 3.0 NA NA

1000 30 1.3 NA NA 1

LD50 from most sensitive laboratory rat acute oral study. 2 LD50 adjusted using the “body weight 3⁄4” adjustment (USEPA 1995, 2011). 3 RQ calculated as accumulated body burden / LD50. 4

 * RQ exceeds Acute Risk LOC. 5 NA- not applicable. Animals consuming bromethalin are not expected to continue feeding on bromethalin bait 

for six days.