Residual Time to 25% Bee Mortality (RT25) Data
On this page:
- RT25 Data: What They are and Where They Come From
- About the RT25 Data Table
- OPP Residual Time to 25% Mortality (RT25)
- Footnotes
- Definitions
- References
RT25 Data: What They are and Where They Come From
The residual time to 25% mortality (referred to as the RT25) values provided in the table below were compiled from registrant-submitted data submitted in order to fulfill the data requirement for Honey Bee (Apis mellifera) Toxicity of Residues on Foliage study (OCSPP Guideline 850.3030a). This study may be conditionally required if the honey bee acute contact (or oral) median lethal dose (LD50) value (obtained from a honey bee acute toxicity test such as OCSPP Guideline 850.3020b) is less than 11 µg/bee1.
The honey bee toxicity of residues on foliage study is a laboratory test designed to determine the length of time over which field weathered foliar residues remain toxic to honey bees, or other species of terrestrial insects. The test substance (e.g., a representative end-use product) is applied to crop foliage, the foliage is harvested at predetermined post-application intervals (i.e., aged residues), and test adult bees are confined on foliage with aged residues for 24 hours. Three treatment intervals (different durations of time that residues are aged between application and harvest) are typically used (e.g., 3, 8 and 24 hours post-application). At a minimum, the test substance should be evaluated at the maximum application rate specified on the product label. If mortality of bees exposed to the foliage harvested 24 hours after the application is greater than 25%, bees should continue to be exposed to aged residues on foliage samples collected every 24 hours (i.e., 48, 72, 96, 120 hours, etc. after the application) until mortality is 25% or less.
About the RT25 Data Table
The table below represents all available RT25 values from studies submitted to the Agency which have undergone quality assurance reviews to ensure that the data are scientifically sound. Depending on the chemical tested, either the technical grade active ingredient or a specific formulation was tested using either the honey bee, alfalfa leaf cutting bee, or alkali bee; the table lists the test material and species tested. The table also denotes the plant species on which residues were aged.
RT25 values are a function of a number of factors including application rate, physical-chemical properties, dissipation, crop, and pesticide formulation. Thus, there is considerable variability in RT25 values within a single formulation, between formulations, between crops, and across application rates. The values included in the database are chemical and formulation specific. There are limited RT25 values available in the table below for the numerous pesticide/formulation/use combinations. This table shows all the data submitted to the Agency that meets the EPA’s quality assurance criteria. EPA plans to update this table as a more robust data set becomes available.
OPP Residual Time to 25% Mortality (RT25)
Active Ingredient |
Formulation 2 |
Application Rate |
Crop 3 |
Qualifier4 |
RT255 |
Test Species Name 6 |
---|---|---|---|---|---|---|
Abamectin (avermectin) |
L 676, 863-28W02 |
0.0016 lb a.i./tree |
citrus |
-- |
60 |
Honey bee |
0.0008 lb a.i./tree |
-- |
41.5 |
||||
0.0008 lb a.i./tree |
-- |
30 |
||||
0.0003 lb a.i./tree |
< |
8 |
||||
0.1 lb a.i./A |
seed alfalfa |
< |
48 |
|||
0.05 lb a.i./A |
-- |
15 |
||||
0.025 lb a.i./A |
< |
8 |
||||
0.0125 lb a.i./A |
< |
4 |
||||
Amitraz |
BTS 27419 EC (20) |
0.033 lb a.i./gal |
apple trees |
-- |
0 |
Honey bee |
Azinphos-methyl |
Guthion® 50 WP (50) |
3 lb a.i./A |
alfalfa |
> |
312 |
Honey bee |
Bifenazate |
Acramite® 50WS (48.8) |
0.733 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
Carbaryl |
80WP (80) |
2 lb a.i./A |
white clover |
> |
42 |
Honey bee |
1 lb a.i./A |
> |
42 |
||||
0.5 lb a.i./A |
> |
42 |
||||
0.25 lb a.i./A |
> |
42 |
||||
Chlorantraniliprole |
35WG (35) |
0.1 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
Chlorfenapyr |
PIRATE® 3 SC (29.8) |
0.34 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
Chlorpyrifos |
Dursban® 4 lb EC |
0.25 lb a.i./A |
alfalfa |
-- |
16 |
Honey bee |
0.5 lb a.i./A |
> |
24 |
||||
1 lb a.i./A |
> |
24 |
||||
0.25 lb a.i./A |
-- |
19 |
Alkali bee |
|||
0.5 lb a.i./A |
> |
24 |
||||
1 lb a.i./A |
> |
24 |
||||
0.25 lb a.i./A |
> |
24 |
Alfalfa Leafcutting bee |
|||
0.5 lb a.i./A |
> |
24 |
||||
1 lb a.i./A |
> |
24 |
||||
Clothianidin |
V-10066 (49.8) |
0.066 lb a.i./A |
alfalfa |
-- |
112 |
Honey bee |
0.132 lb a.i./A |
-- |
179 |
||||
0.198 lb a.i./A |
-- |
512 |
||||
Cymoxanil |
Cymoxanil/ Famoxadone 50WG (25/25) |
0.1875 lb a.i./A |
alfalfa |
< |
1 |
Honey bee |
Cypermethrin |
Cymbush® 3E (35.6) |
0.06 lb a.i./A |
oilseed rape |
> |
96 |
Honey bee |
0.14 lb a.i./A |
> |
96 |
||||
Deltamethrin |
Decis® EC (20) |
0.02 lb a.i./A |
alfalfa |
-- |
5.2 |
Honey bee |
Diazinon |
40 WP (40) |
1 lb a.i./A |
white clover |
> |
42 |
Honey bee |
0.5 lb a.i./A |
> |
42 |
||||
0.25 lb a.i./A |
< |
42 |
||||
0.125 lb a.i./A |
< |
42 |
||||
Dichlorvos |
50 EC (50) |
0.31 lb a.i./A |
white clover |
< |
3 |
Honey bee |
0.155 lb a.i./A |
< |
3 |
||||
0.077 lb a.i./A |
< |
3 |
||||
0.039 lb a.i./A |
< |
3 |
||||
0.019 lb a.i./A |
< |
3 |
||||
DDVP 4E (42.39) |
0.5 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
|
Dicrotophos |
9 lb EC |
0.5 lb a.i./A |
alfalfa |
< |
48 |
Honey bee |
0.5 lb a.i./A |
> |
48 |
Alfalfa Leafcutting bee |
|||
0.5 lb a.i./A |
> |
48 |
Alkali bee |
|||
Dimethoate |
2.67 lb EC |
0.5 lb a.i./A |
alfalfa |
< |
120 |
Honey bee |
0.5 lb a.i./A |
< |
120 |
Alfalfa Leafcutting bee |
|||
0.5 lb a.i./A |
> |
72 |
Alkali bee |
|||
Dinotefuran |
MTI-446 20 SG |
0.134 lb a.i./A |
alfalfa |
-- |
39 |
Honey bee |
Disulfoton |
Di-System® 8 EC |
1 lb a.i./A |
alfalfa |
-- |
5.5 |
Honey bee |
D-phenothrin |
Multicide® 2798 D-phenothrin/ Prallethrin/ PBO (5/1/5) |
0.0008 lbs a.i./A prallethrin; |
alfalfa |
< |
3 |
Honey bee |
Emamectin benzoate |
MK-244 (TGAI, 97.5) |
0.015 lb a.i./A |
alfalfa |
-- |
11 |
Honey bee |
Endosulfan |
35 EC (35) |
0.77 lb a.i./A |
clover blossoms |
< |
3 |
Honey bee |
Etofenprox |
RF2056 OL (20) |
0.007 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
Famoxadone |
Cymoxanil/ Famoxadone 50WG (1:1) (25/25) |
0.1875 lb a.i./A |
alfalfa |
< |
1 |
Honey bee |
Fenazaquin |
GWN-1708 (18.53) |
0.45 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
Fenbutatin oxide |
SD 14114 50WP (50) |
1.75 lb a.i./A |
cherry limbs |
< |
3 |
Honey bee |
0.4375 lb a.i./A |
< |
3 |
||||
Fenitrothion |
Sumithion® 8 EC |
0.5 lb a.i./A |
alfalfa |
< |
24 |
Honey bee |
1 lb a.i./A |
-- |
101 |
||||
0.5 lb a.i./A |
-- |
106 |
Alfalfa Leafcutting bee |
|||
1 lb a.i./A |
> |
120 |
||||
0.5 lb a.i./A |
-- |
98 |
Alkali bee |
|||
1 lb a.i./A |
> |
120 |
||||
Fenpropathrin |
Danitol® 2.4 EC |
0.1 lb a.i./200 gal/A |
Valencia Orange trees |
< |
192 |
Honey bee |
0.2 lb a.i./200 gal/A |
-- |
276 |
||||
0.4 lb a.i./200 gal/A |
< |
336 |
||||
Fenvalerate |
Pydrin® 2.4 lb/gal EC |
0.1 lb a.i./A |
alfalfa |
-- |
7 |
Honey bee |
0.4 lb a.i./A |
> |
8 |
||||
0.4 lb a.i./A |
alfalfa |
> |
8 |
Honey bee |
||
0.1 lb a.i./A |
-- |
7 |
||||
0.4 lb a.i./A |
> |
8 |
Alkali bee |
|||
0.1 lb a.i./A |
-- |
7 |
||||
0.4 lb a.i./A |
> |
8 |
Alfalfa Leafcutting bee |
|||
0.1 lb a.i./A |
> |
8 |
||||
Flutolanil |
Moncut® Dry Flowable (65) |
0.327 lb a.i./A |
rapeseed |
-- |
0 |
Honey bee |
Fonofos |
EC |
2 lb a.i./A |
alfalfa |
< |
8 |
Honey bee |
1 lb a.i./A |
< |
3 |
||||
Gamma cyhalothrin |
XR-225. GF-231 (14.7) |
0.015 lb a.i./A |
alfalfa |
> |
24 |
Honey bee |
Imidacloprid |
NTN 33893 240FS |
0.1 lb a.i./A |
alfalfa |
< |
2 |
Honey bee |
0.1 lb a.i./A |
< |
2 |
Alfalfa Leafcutting bee |
|||
0.1 lb a.i./A |
< |
8 |
Alkali bee |
|||
0.5 lb a.i./A |
alfalfa |
-- |
8 |
Honey bee |
||
0.167 lb a.i./A |
< |
2 |
||||
0.045 lb a.i./A |
< |
2 |
||||
Indoxacarb |
30WG (30.7) |
0.15 lb a.i./A |
alfalfa |
-- |
24 |
Honey bee |
Lambda-Cyhalothrin |
EC |
0.013 lb a.i./A |
alfalfa |
-- |
22 |
Honey bee |
0.031 lb a.i./A |
-- |
54 |
||||
Lindane |
20 EC (20) |
1.5 lb a.i./A |
alfalfa |
-- |
72 |
Honey bee |
1 lb a.i./A |
-- |
72 |
||||
0.5 lb a.i./A |
-- |
24 |
||||
25WP (25) |
1.5 lb a.i./A |
-- |
72 |
|||
1 lb a.i./A |
-- |
72 |
||||
0.5 lb a.i./A |
-- |
24 |
||||
40 F (40) |
1.5 lb a.i./A |
-- |
72 |
|||
1 lb a.i./A |
-- |
72 |
||||
0.5 lb a.i./A |
-- |
24 |
||||
Malathion |
57 EC (57) |
1.6 lb a.i./A |
alfalfa |
< |
24 |
Honey bee |
Methidathion |
Supracide® 2E (25.2) |
5 lb a.i./A |
alfalfa |
-- |
114 |
Honey bee |
Methyl parathion |
450g/L CS |
0.4 lb a.i./A |
alfalfa |
-- |
207 |
Honey bee |
0.4 lb a.i./A |
-- |
171 |
||||
Mevinphos |
SC (89.5) |
0.81 lb a.i./A |
alfalfa |
< |
4 |
Honey bee |
Oxamyl |
Vydate® L (24) |
1 lb a.i./A |
alfalfa |
> |
144 |
Honey bee |
24L (24) |
1 lb a.i./A |
alfalfa |
-- |
22 |
Honey bee |
|
2 lb a.i./A |
-- |
75 |
||||
Parathion |
4 lb E |
0.5 lb a.i./A |
clover |
> |
24 |
Honey bee |
Phosalone |
3 lb EC (NA) |
1.5 lb a.i./A |
alfalfa |
< |
3 |
Alkali bee |
1.5 lb a.i./A |
< |
3 |
Alfalfa Leafcutting bee |
|||
Phosmet |
50W (50) |
0.5 lb a.i./A |
alfalfa |
-- |
51 |
Honey bee |
1 lb a.i./A |
> |
24 |
||||
50WP (50) |
1 lb a.i./A |
alfalfa |
> |
3 |
Honey bee |
|
1 lb a.i./A |
> |
3 |
Alfalfa Leafcutting bee |
|||
1 lb a.i./A |
> |
3 |
Alkali bee |
|||
Piperonyl butoxide |
Multicide® 2798 D-phenothrin/ Prallethrin/ PBO (5/1/5) |
0.0008 lbs a.i./A prallethrin; 0.0036 lb a.i./A d-phenothrin; and 0.0038 lbs a.i./A PBO |
alfalfa |
< |
3 |
Honey bee |
Scourge® [Piperonyl butoxide/ Resmethrin mixture] (46/18) |
0.007 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
|
Prallethrin |
LX119-04 (ETOC) L (2.45) |
0.005 lb a.i./A |
alfalfa |
< |
8 |
Honey bee |
Multicide® 2798 D-phenothrin/ Prallethrin/PBO (5/1/5) |
0.0008 lbs a.i./A prallethrin; 0.0036 lb a.i./A d-phenothrin; and 0.0038 lbs a.i./A PBO |
alfalfa |
< |
3 |
Honey bee |
|
Propoxur |
50WP (50) |
0.75 lb a.i./A |
alfalfa |
> |
5 |
Honey bee |
Pyridaben |
BAS 300 WP (76.8) |
0.5 lb a.i./A |
alfalfa |
-- |
20 |
Honey bee |
Resmethrin |
Scourge® [Piperonyl butoxide/ Resmethrin mixture] (46/18) |
0.007 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
Spinetoram |
GF-1640 (24.7) |
0.109 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
Spinosad |
NAF-315 (23.5) |
0.16 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
0.16 lb a.i./A |
alfalfa |
< |
3 |
Honey bee |
||
Spiroxamine |
KWG 4168 300CS (32.4) |
0.54 lb a.i./A |
alfalfa |
< |
2 |
Honey bee |
Thiacloprid |
YRC 2894 (41.9) |
0.16 lb a.i./A |
alfalfa |
< |
2 |
Honey bee |
Thiamethoxam |
CGA-293343 (25.5) |
0.004 lb a.i./A |
alfalfa |
< |
24 |
Honey bee |
0.088 lb a.i./A |
> |
72 |
||||
Tralomethrin |
HAG-107 0.3 lb EC |
0.015 lb a.i./A |
alfalfa |
< |
0.5 |
Honey bee |
Footnotes
1 U.S. CFR 40 Part 158 Subpart G §158.630, Test Note no. 24: Data are required only when the formulation contains one or more active ingredients having an acute LD50 of <11 micrograms per bee as determined in the honey bee acute contact study [OCSPP 850.3020] and the use pattern(s) indicate(s) that honey bees may be exposed to the pesticide.
2 End use product tested. % active ingredient (a.i.) is provided where available. Product names where specified are listed; otherwise, product codes are listed
3 Agricultural commodity used in study.
4 Less than (<) value indicates that there was less than 25% mortality at the shortest aged foliage tested; greater than (>) value indicates that there was greater than 25% mortality at the longest aged residue tested; equal value (--) indicates that 25% mortality was reported at the time documented in the next column.
5 Residual Time to 25% mortality. This is the length of time post-application that residues of the test substance on foliage are toxic to 25% of honey bees tested.
6 Species tested in the submitted study. Apis mellifera (honey bee); Aphidius rhopalosiphi (parasitic wasp); Aphytis lignanensis (parasitic wasp); Aphytis melinus (parasitic wasp); Chrysoperla carnea (green lacewing); Copidosoma truncatellus (parasitic wasp); Diglyphus intermedius (parasitic wasp); Megachile pacifica (Alfalfa leafcutting bee); Megachile rotundata (Alfalfa leafcutting bee); Metaphycus luteolus (parasitic wasp); Nomia melanderi (alkali bee); Opius bruneipus (parasitic wasp); Stethorus punctum (ladybird beetle); Telenomus remus (parasitic wasp); Typhlodromus pyri (predatory mite).
Definitions
a.i. = active ingredient
CS = capsule suspension
E = emulsifiable
EC = emulsifiable concentrate
F = flowable
L = liquid
OL = liquid formulation
RT25 = residual time to 25% mortality
SC = soluble concentrate
SG = soluble granule
TGAI = technical grade active ingredient
W = wettable powder
WDG = water dispersible granular
WG = wettable granule
WP = wettable powder
WS = water soluble
Other letter/number combinations specified in the formulation column of the table refer to product codes and are not defined.
References
aUSEPA. 2012. Ecological Effects Test Guidelines: OCSPP 850.3030: Honey Bee Toxicity of Residues on Foliage. United States Environmental Protection Agency, Office of Chemical Safety and Pollution Prevention, EPA 712-C-018. January 2012.
bUSEPA. 2012. Ecological Effects Test Guidelines: OCSPP 850.3020: Honey Bee Acute Contact Toxicity Test. United States Environmental Protection Agency, Office of Chemical Safety and Pollution Prevention, EPA 712-C-019. January 2012.