Concentration and Aquatic Toxicity of RIFA Insecticides and Other
Organophosphates in Surface Water March 1999-June 2000
Dave Kim, Johanna Walters, Kean S. Goh August 29, 2000
Irvine, CA
Outline
• Introduction
• Monitoring
• Concentration vs toxicity
• Urban vs. Nurseries
• Irrigation Runoff vs. Storm Runoff
• Runoff mitigations
• Conclusions
The Insecticides
• Bifenthrin (Talstar®)
• Chlorpyrifos (Dursban®)
• Fenoxycarb (Award®)
• Hydramethylnon (Amdro®)
• Pyriproxyfen (Distance®)
• Diazinon
Aquatic Toxicity (LC50 ppb)
Chemical R. Trout D. magna C. dubia
Bifenthrin 0.15 0.16 na
Chlorpyrifos 3 1.7 0.13
Diazinon 2600 0.96 0.51
Fenoxycarb 1600 400 na
Hydramethylnon 160 1140 na
Malathion 170 1.8 1.14
Pyriproxyfen >325 400 na
Newport Bay Watershed
• Bee Canyon (el modeno) @ Portola Pkwy
• Hines Channel (Hines)
• Marshburn (Bordiers) @ Irvine Blvd
• San Diego Creek @ Campus Dr.
• Bonita Creek @ San Diego Ck
• Westcliff Park Channel
Irrigation Runoff
Bee Canyon
0
12
34
56
78
9
Jun-99
Sep-99
Oct-99
Dec-99
Jan-00
Feb-00
Mar-00
Apr-00
May-00
Jun-00
Month
Con
cent
ratio
n (p
pb)
bifenthrin
fenoxycarb
chlorpyrifos
diazinon
malathion
Bee Canyon
0123456789
10
Jun-99Sep-99Oct-99 Dec-99
Jan-00Feb-00 Mar-00
Apr-00 May-00
Jun-00
Month
Con
cent
ratio
n (p
pb)
0
1020
30
40
5060
70
8090
100
Mor
talit
y of
C
. dub
ia (%
)
diazinon
chlorpyrifos
fenoxycarb
bifenthrin
% 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
ratio
n (p
pb)
bifenthrin
fenoxycarb
chlorpyrifos
diazinon
dimethoate
malathion
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
ratio
n (p
pb)
0
1020
30
40
5060
70
8090
100
Mor
talit
y of
C
. dub
ia (%
)
malathion
dimethoate
diazinon
chlorpyrifos
fenoxycarb
bifenthrin
% mortality
Marshburn Slough
0
1
2
3
Feb-00
Con
cent
rati
on (
ppb) bifenthrin
chlorpyrifos
diazinon
malathion
Marshburn Slough
0
1
2
3
4
Feb-00
Con
cent
rati
on (
ppb)
0
10
20
30
40
50
60
70
80
90
100
Mor
talit
y of
C
. dub
ia (%
)
malathion
diazinon
chlorpyrifos
bifenthrin
% mortality
San Diego Creek
0
1
2
Con
cent
ratio
n (p
pb)
chlorpyrifos
diazinon
dimethoate
fonofos
malathion
San Diego Creek
0
1
2
Con
cent
ratio
n (p
pb)
0102030405060708090100
Mor
talit
y of
C.
dub
ia (%
) malathion
fonofos
dimethoate
diazinon
chlorpyrifos
% mortality
Bonita Creek
0
1
2
Sep-99 Oct-99 Dec-99 Jan-00 Feb-00 Mar-00 Apr-00 May-00 Jun-00
Con
cent
ratio
n (p
pb)
diazinon
malathion
Bonita Creek
0
1
2
Sep-99
Oct-99
Dec-99
Jan-00
Feb-00
Mar-00
Apr-00
May-00
Jun-00
Con
cent
ratio
n (p
pb)
0102030405060708090100
Mor
talit
y of
C
. dub
ia (%
)
malathion
diazinon
% 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
ratio
n (p
pb)
0
10
20
30
40
5060
70
80
90
100
Mor
talit
y of
C
. dub
ia (%
)
malathion
diazinon
chlorpyrifos
% mortality
Storm Runoff
Hines Channel
0
0.5
1
1.5
1 2 3 4 5 6
Sampling Interval
Co
ncen
tratio
n (
pp
b)
0
1
2
3
4
5
6
Bif
en
th
rin
co
ncen
tratio
n
(p
pb
)
fenoxycarb hydramethylnon pyriproxyfen
chlopyrifos diazinon malathion
bifenthrin
Marshburn Slough
0
0.5
1
1.5
1 2 3 4 5 6
Sampling Interval
Co
ncen
tratio
n (
pp
b)
0
1
2
3
4
5
6
Bif
en
th
rin
co
ncen
tratio
n
(p
pb
)
fenoxycarb hydramethylnon pyriproxyfen
chlopyrifos diazinon malathion
bifenthrin
San Diego Creek
0
0.5
1
1.5
1 2 3 4 5 6
Sampling Interval
Co
ncen
tratio
n (
pp
b)
0
1
2
3
4
5
6
fenoxycarb hydramethylnon pyriproxyfen
chlopyrifos diazinon malathion
bifenthrin
Westcliff Park
0
0.5
1
1.5
1 2 3 4 5 6
Sampling Interval
Co
ncen
tratio
n (
pp
b)
0
1
2
3
4
5
6
fenoxycarb hydramethylnon pyriproxyfen
chlopyrifos diazinon malathion
bifenthrin
Mitigation
Application Runoff
Conclusions
Detections: Irrigation Runoff
• Single detect: hydramethylnon, pyriproxyfen
• Nursery: Bifenthrin, Diazinon, Chlorpyrifos, Malathion, Dimethoate <8 ppb
• Urban: Diazinon, Malathion, Chlorpyrifos <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
Toxicity: Storm Runoff
• Nursery– All 18 samples 100% mortality
• Bifenthrin, Diazinon, Malathion, Chlorpyrifos
• Urban– All 18 samples 100% mortality
• Diazinon, Malathion, Chlorpyrifos • Unknown
Prevention & Mitigation
Insecticide Formulation & Application
Irrigation Management
Tailwater Recovery
Buffer Strip
Acknowledgments
California Dept of Food and Agriculture Center for Analytical Chemistry Department of Fish and Game
UC Cooperative ExtensionCounty Dept of Agriculture
Nurseries
