1
Concentration and Aquatic Toxicity of RIFA Insecticides and Other
Organophosphates in Surface WaterMarch 1999-June 2000
Dave Kim, Johanna Walters, Kean S. GohDepartment of Pesticide Regulation
September 14, 2000UC Riverside, CA
Outline
• Introduction • Monitoring • Irrigation Runoff vs. Storm Runoff • Urban vs. Nurseries• Regulatory Approach • Runoff mitigations• Conclusions
The Insecticides
• Bifenthrin (Talstar®)• Chlorpyrifos (Dursban®)• Fenoxycarb (Award®)• Hydramethylnon (Amdro®)• Pyriproxyfen (Distance®)• Diazinon
Aquatic Toxicity (LC50 ppb)
1.141.8170Malathion
na 400>325Pyriproxyfen
na 1140160Hydramethylnon
na4001600Fenoxycarb
0.510.962600Diazinon
0.131.73Chlorpyrifos
na0.160.15Bifenthrin
C. dubia D. magna
R. TroutChemical
San Joaquin Marsh Preserve
Newport Bay Ecological Reserve
2
Irrigation Runoff
Bee Canyon
0123456789
Jun-99
Sep-99
Oct-99
Dec-99
Jan-00
Feb-00
Mar-00
Apr-00
May-00
Jun-00
Month
Con
cent
rati
on (
ppb)
bifenthrinfenoxycarbchlorpyrifosdiazinonmalathion
Bee Canyon
0123456789
10
Jun-99Sep-99Oct-99 Dec-99
Jan-00Feb-00 Mar-00
Apr-00 May-00
Jun-00
Month
Con
cent
rati
on (
ppb)
0102030405060708090100
Mor
talit
y of
C. d
ubia
(%
)
diazinonchlorpyrifosfenoxycarbbifenthrin% mortality
Central Irvine/ Hines Channel
0
1
2
3
4
5
May-99
Jun-99
Sep-99
Oct-99
Dec-99
Jan-00
Feb-00
Mar-00
Apr-00
May-00
Jun-00
Month
Con
cent
rati
on (
ppb)
bifenthrinfenoxycarbchlorpyrifosdiazinondimethoatemalathion
Central Irvine/ Hines Channel
0
1
2
3
4
5
May-99
Jun-99
Sep-99
Oct-99
Dec-99
Jan-00
Feb-00
Mar-00
Apr-00
May-00
Jun-00
Month
Con
cent
rati
on (
ppb)
0102030405060708090100
Mor
talit
y of
C. d
ubia
(%
)
malathiondimethoatediazinonchlorpyrifosfenoxycarbbifenthrin% mortality
Bordier's
0
1
2
3
4
5
Jun-99
Sep-99
Oct-99
Dec-99
Jan-00
Feb-00
Mar-00
Apr-00
May-00
Jun-00
Con
cent
rati
on (
ppb)
bifenthrinchlorpyrifosdiazinonmalathion
3
San Diego Creek
0
1
2
Mar
-99
Apr
-99
May
-99
Jun-
99Se
p-99
Oct
-99
Dec
-99
Jan-
00Fe
b-00
Mar
-00
Apr
-00
May
-00
Jun-
00
Con
cen
trat
ion
(p
pb
) chlorpyrifosdiazinondimethoatemalathion
San Diego Creek
0
1
2
Mar
-99
Apr
-99
May
-99
Jun-
99Se
p-99
Oct
-99
Dec
-99
Jan-
00Fe
b-00
Mar
-00
Apr
-00
May
-00
Jun-
00
Con
cen
trat
ion
(p
pb
)
0102030405060708090100
Mor
tali
ty o
f C. d
ubia
(%
)
malathiondimethoatediazinonchlorpyrifos% mortality
Westcliff Park
0
1
2
3
Dec-99 Jan-00 Feb-00 Apr-00 May-00 Jun-00
Con
cent
ratio
n (p
pb)
chlorpyrifos
diazinon
malathion
Westcliff Park
0
1
2
3
Dec-99 Jan-00 Feb-00 Apr-00 May-00 Jun-00
Con
cent
rati
on (
ppb)
0102030405060708090100
Mor
talit
y of
C. d
ubia
(%
)
malathion
diazinon
chlorpyrifos
% mortality
Storm Runoff
Marshburn Slough
0
0.5
1
1.5
1 2 3 4 5 6
Sampling Interval
Conc
entra
tion (
ppb)
0
1
2
3
4
5
6
Bifen
thrin
conc
entra
tion
(ppb)
feno xycarb hydramethylno n pyripro xyfenchlo pyrifo s diazino n mala thio n
bifenthrin
4
San Diego Creek
0
0.5
1
1.5
1 2 3 4 5 6
Sampling Interval
Conc
entra
tion (
ppb)
0
1
2
3
4
5
6
feno xycarb hydramethylno n pyripro xyfenchlo pyrifo s diazino n mala thio n
bifenthrin
Westcliff Park
0
0.5
1
1.5
1 2 3 4 5 6
Sampling Interval
Conc
entra
tion (
ppb)
0
1
2
3
4
5
6
feno xycarb hydramethylno n pyripro xyfenchlo pyrifo s diazino n mala thio n
bifenthrin
Regulatory MAA
• Preventive (outreach and education)• Self-regulatory (voluntary programs)• Regulatory (DPR)• Regulatory (Federal and Regional Boards)
Mitigation
Application Runoff
6
Canna Filter Strip (June 2000)
00.10.20.30.40.50.60.70.80.9
bife
nthr
in
diaz
inon
met
hida
thio
n
Co
nce
ntr
atio
n (p
pb
)
Inflow Outflow
Conclusions
Detections: Irrigation Runoff
• Single detect: hydramethylnon, pyriproxyfen
• Nursery: Bifenthrin, Diazinon, Chlorpyrifos, Malathion, Dimethoate <8 ppb
• Urban: Diazinon, Malathion, Chlorpyrifos, Dimethoate <1.5 ppb
Detections: Storm Runoff
• Nursery–bifenthrin, diazinon, malathion,
chlorpyrifos, fenoxycarb <6 ppb• Urban
–diazinon, malathion, chlorpyrifos <1.5 ppb
Toxicity: Irrigation Runoff• Nursery sites:
– 18: Bifenthrin, Diazinon, Chlorpyrifos, Malathion– 1 unknown– 2 non toxic
• Urban and integrated sites:– 27:Diazinon, Malathion, Chlorpyrifos – 27 unknown – 21 non toxic
7
Toxicity: Storm Runoff
• Nursery– All 18 samples 100% mortality
• Bifenthrin, Diazinon, Malathion, Chlorpyrifos
• Urban– All 18 samples 100% mortality
• Diazinon, Malathion, Chlorpyrifos • Unknown
Prevention & MitigationInsecticide Application Irrigation ManagementWater RecoveryHolding Pond Buffer Strip
Acknowledgments
California Dept of Food and Agriculture Center for Analytical Chemistry Department of Fish and Game
Orange County Dept of AgricultureRegional Water Quality Control Board
UC Cooperative ExtensionBordiers Nursery
el modeno GardensHines Nursery