Nov 1, 2012 ... Pesticides Pollutants. From Urban Landscapes ... aquatic food chain. Much of it is
coming .... Concentrations are in ng/L (ppt). 96 hr LC50.
Pesticides Pollutants From Urban Landscapes Why Landscape Runoff Matters Loren Oki CE Specialist, Landscape Horticulture Departments of Plant Sciences and Environmental Design Ant IPM Conference November 1, 2012
Photo: L.Oki
Sacramento Bee July 14, 2006
The Mayhew Drain in the Rancho Cordova area carries stormwater to the American River. A new study found enough pyrethroid pesticides in the American River to kill tiny shrimp – among the first links in the aquatic food chain. Much of it is coming from Sacramento’s runoff, the study found.
Pesticide Application About 50% of all pesticides purchased by homeowners are used to control ants
Irrigation Management
Photos: D. Haver
“Urban Drool”
Photos: D. Haver
Proper Design and Management
Photos: L. Oki
Proper Design and Management
Photo: L.Oki
Photo: D. Haver
Photos: L. Oki
Proper Design and Management
Photos: D. Haver
Photo: D. Haver
Photo: L. Oki
Photo: L. Oki
Pesticides in Urban Runoff Runoff Monitoring
• Continuous Data Collection – – – – –
Flows (depth & velocity) Temperature pH Electrical conductivity Rainfall
• Automated Stormwater Sampling • Remote Communication Photos: L.Oki
Pesticides in Urban Runoff Runoff Monitoring
• Continuous Data Collection – – – – –
Flows (depth & velocity) Temperature pH Electrical conductivity Rainfall
Photos: L.Oki
Dry season runoff patterns Daily Periodicity 8
7
Tue July 1
Wed July 2
Thu July 3
Fri July 4
Sat July 5
Sun July 6
Mon July 7
Water Depth (cm)
6
5
4
3
2
1
0 0:00
12:00
0:00
12:00
0:00
12:00
0:00
12:00
0:00
Time of Day
12:00
0:00
12:00
0:00
12:00
0:00
Dry season runoff patterns Daily Periodicity 8
7
Tue July 1
Wed July 2
Thu July 3
Fri July 4
Sat July 5
Sun July 6
Mon July 7
Water Depth (cm)
6
5
4
3
2
1
0 0:00
12:00
0:00
12:00
0:00
12:00
0:00
12:00
0:00
Time of Day
12:00
0:00
12:00
0:00
12:00
0:00
Water Sample Collection Sacramento County UC Master Gardeners
Photo: L.Oki
Photo: L.Oki
Water Sample Collection Sampling Schedule Q1
Q2
2006
Q3
Q4
Weekly*
Weekly
2007
Biweekly
Weekly
Weekly
Weekly
2008
Biweekly
Biweekly
Biweekly
Weekly
2009
Monthly
Monthly*
None
None
2010
None
Monthly
Monthly
Monthly
• Up to 5 early storms of each season
% Detection 80
80
70
70
60
60
50
50
40
40
30
30
20
20
10
10
0
0
Deltamethrin
Esfenvalerate
Cypermethrin
Cyfluthrin
trans-Permethrin
90
cis-Permethrin
L-Cyhalothrin
Fenpropathrin
Sacramento County
Bifenthrin
Fipronil
n=62
Chlorpyrifos
100
Diazinon
Deltamethrin
Esfenvalerate
Cypermethrin
Cyfluthrin
trans-Permethrin
90
cis-Permethrin
L-Cyhalothrin
Fenpropathrin
Bifenthrin
Fipronil
Chlorpyrifos
Diazinon
Pesticide Detection Rates Orange County
100
n=49
Pesticide Concentration Orange County neighborhoods Site A Max
Site B
Median
Max
Site C
Median
Max
Site D
Median
Max
Median
diazinon
2,086
2.8
63.9
1.2
344
4.3
253
2.6
fipronil
10,004
75.4
382
76.6
1,652
129
656
119
287
36.5
138
12.6
6,121
12.9
709
13.9
bifenthrin no. samples
49
52
53
Concentrations are in ng/L (ppt) 96 hr LC50
organism
diazinon
436
Ceriodaphnia dubnia
fipronil
140
Americamysis bahia
bifenthrin bifenthrin
50 1-3
Ceriodaphnia dubnia Hyalella azteca
44
The Metabolite Issue fipronil • Anaerobic conditions (reduction) → fipronil sulfide
• Aerobic conditions (oxidation) → fipronil sulfone
• Photochemical (photolysis) → desthiofipronil
Fipronil Toxicity Aquatic
LC50
Rainbow trout
248 ppb
Bluegill
85 ppb
Sheepshead minnow
130 ppb
Grass shrimp
0.32 ppb
Mysid shrimp
0.14 ppb
Daphnid Degradate
190 ppb Relative Toxicity Approx ½ life (d)
Fipronil sulfone
~6x
500-600
Fipronil sulfide
~2x
200-350
Desthiofipronil
~8x
200-500
The toxicity of pollutants is sometimes measured in parts per trillion (ppt). If Folsom Lake holds 1 million acre-feet at capacity, how much is 1ppt in that lake? 1. 2. 3. 4. 5.
A can of soda (12 oz.) A 2 liter soda bottle A 55 gallon drum A railcar (22,800 gal) The UC Davis water tower (200,000 gal) 6. An olympic-size swimming pool (660,000 gal)
The toxicity of pollutants is sometimes measured in parts per trillion (ppt). If Folsom Lake holds 1 million acre-feet at capacity, how much is 1ppt in that lake? • Convert acre-feet to liters 325,851 gal/acre-foot and 3.785 L/gal • Folsom Lake is 325,851,429,000 gals or 1,233,477,999,337 liters • That’s 1.2 trillion liters • So, 1ppt in Folsom Lake is 1.2 liter
Controlling Pollutants in Runoff Objectives • Coordinate applications with irrigation and rain • Prevent applications to irrigated locations that generate runoff • Don’t generate runoff Proper irrigation system design and management • Hold runoff on-site “Water that falls on the site, stays on the site”
Thank you
[email protected]
Basic Properties of Fipronil Property
Value
Ranking
Solubility
2 ppm
Moderate
Adsorption (Koc)
800
Low-Moderate
Hydrolysis T1/2
>100 days
Stable
Turf T1/2
12-15 days
Short
Bare soil T1/2
33-75 days
Moderate
* Sulfone and sulfide have higher Koc. Fate in sediment or water unknown.
