Pesticides in Urban Runoff & Waterways Nan Singhasemanon Staff Environmental Scientist CA Department of Pesticide Regulation Alliance Conference, San Jose 2009 1
Overview of Urban Pesticide Use 2
Urban Pesticide Use Settings 3
4 Pesticide Use in Urban Areas Is there really that much use in urban areas? DPR s PUR is great for tracking Ag. use but urban? How much urban use compared to Ag. use? Retail sales = total sales total reported use Urban Use = retail sales + reported urban use As much as ½ of pesticide use in CA occurs in urban areas Urban pesticide use = small but countless applications
5 Urban Users/Sources Many user groups generally divided into: Licensed/Certified users Pest control businesses Other users that hold a QAL or QAC Private applicators Home owners Other users of general use pesticide in various settings
User Groups Relevant to Urban W.Q. Urban outdoor applicators: Home owners/tenants Small business owners & employees Pest control businesses Maintenance gardeners Groundskeepers & maintenance workers (municipal, private, industrial, institutional) Home & Garden store, nursery workers Vector control district & pest eradication program workers Ag. applicators in urban areas 6
A Look Back 7
8 Organophosphorus Pesticides (OPs) Monitoring in 1990 s & early 2000 s Early work in Alameda Co. on diazinon & chlorpyrifos Creek levels > W.Q. standards for protection of aquatic life Toxicity to aquatic invertebrates (Ceriodaphnia dubia) Suspected cause: outdoor residential use of OPs Regional Boards began regulating discharges of OPs to urban waterways (Waters of the State) Registrants voluntarily canceled outdoor residential uses Diazinon & chlorpyrifos levels dropped Water column toxicity subsided
9 Replacing the OPs However need to control pests remained Integrated pest management (IPM) to fill void? Replacement insecticides? Water quality problems from replacements? Herbicides, fungicides & antimicrobial products are also used What are the potential impacts of the current crop of pesticides?
DPR Urban Pesticide Monitoring Project 10
Urban Pesticide Monitoring Project 2008 DPR monitoring study to assess the occurrence & magnitude of pesticides in urban runoff & waterways Need for ongoing & comprehensive surveillance monitoring Which pesticides? What concentrations? How frequent? Storm runoff vs. baseflow (drool)? Receiving water vs. storm drain? Are pesticides @ levels that are toxic to aquatic organisms? 11
12 Urban Pesticide Monitoring Project Areas of focus: Sacramento, East Bay, Orange Co. & San Diego Co. 7 receiving water & 18 storm drain sites So far, 3 storm events, 3 baseflow events, & one sediment collection 64 insecticides, herbicides & degradates (7 groups)
Lots of Urban Products & A.I. s What active ingredients are used? PUR s reported urban use Residential use surveys Retail shelf surveys How do we determine which pesticides could be a concern for urban water quality? Use Amount Number of Products Application Rate Site of Application Formulation Toxicity Physico-Chemical Characteristics 13
Urban Areas w/ Ag. Sources Omitted 14
15 Types of Sampling Sites Dublin Storm Drain MCC010 Martin Canyon/Big Canyon Cr. & 680
16 Water Results Preliminary data Detection frequencies: wet-weather > dryweather (but there in drool) Concentrations: storm drain sites > receiving water sites Frequency of detection: Orange Co. > Sacramento Co. > S.F. Bay > San Diego
Overall Detection Frequencies Insecticides Total Samples % Detects Bifenthrin 11 100 Desulfinyl fipronil 138 76 Fipronil sulfone 138 74 Fipronil 138 70 Fipronil amide 138 60 Fipronil sulfide 138 48 Permethrin 11 45 Desulfinyl fipronil amide 138 42 Carbaryl 134 26 Malathion 105 19 Chlorpyrifos 105 7 Diazinon 105 7 17
Overall Detection Frequencies Herbicides Total Samples % Detects 2,4-D 114 67 Triclopyr 114 58 Diuron 117 53 Dicamba 114 42 MCPA 113 28 Pendimethalin 126 26 Simazine 117 21 Prodiamine 127 20 Oryzalin 126 12 Prometon 117 8 18
Orange Co. vs. San Diego Co. 120 100 80 60 57 OC N = 21 100 100 100 95 100 100 67 90 86 95 40 40 29 43 20 0 5 5 5 19 Carbaryl Pendimethalin Prodiamine Desulfinyl fipronil Fipronil sulfone Fipronil Fipronil amide Fipronil sulfide Desulfinyl fipronil amide Malathion 2,4-D Triclopyr Dicamba MCPA Diuron Simazine Prometon DN FP Pesticides PX TR 120 Credit: Li-Ming He, Environmental Monitoring Branch, DPR 2008 100 80 60 40 20 0 7 0 0 20 13 0 0 0 0 0 13 7 0 0 0 27 7 Carbaryl Pendimethalin Prodiamine Desulfinyl fipronil Fipronil sulfone Fipronil Fipronil amide Fipronil sulfide Desulfinyl fipronil amide Malathion 2,4-D Triclopyr Dicamba MCPA Diuron Simazine Prometon Pesticides %Detects %Detects DN SD N = 15 FP PX TR
Pyrethroids in Urban Sediment: Bifenthrin > cyfluthrin = permethrin > deltamethrin/tralomethrin > λ-cyhalothrin > cypermethrin 100 80 87 78 N = 23 78 60 40 57 43 36 20 17 0 0 0 20 %Detects Bifenthrin Cyfluthrin Cypermethrin Deltamethrin/tralomethrin Fenopropathrin Fenvalerate/esfenvalerate Lambda-cyhalothrin Permethrin Resmethrin Pyrethroids Credit: Li-Ming He, Environmental Monitoring Branch, DPR 2008
21 Comparison w/ Toxicity Thresholds Water (some samples) Bifenthrin above Hyalella azteca LC 50 Fipronil above Mysidopsis bahia LC 50 Diuron above EC 50 for a green alga Sediment (some samples) Bifenthrin above Hyalella azteca LC 50 What do these exceedences mean??? Threat to beneficial uses & violation of WQOs? Potential population or ecological-level impact? Impacts to endangered species?
Key Findings from Other Studies Urban runoff contains a pesticide soup Pesticides do not just run off from residential areas! (just most investigated) Other urban land uses Ants! Ants! Ants! Ant control drives much of urban insecticide demand & use in CA Pyrethroids (e.g., bifenthrin) are frequently found: Source investigations point to Outdoor uses by both licensed & non-licensed applicators Wastewater Treatment Concern 22
Why is All This Important & What is Being Done? 23
24 Why is this Important? State & Regional Boards have legal mandate to protect W.Q. Could initiate regulations & discharge permitting process based on toxicity linked to pesticides Municipal stormwater programs are responsible dischargers Problem they cannot control use or users Face fines & vulnerable to litigation (i.e., law$uit$) DPR also has legal mandate to prevent significant adverse effects to the environment
25 Current Mitigation Existing environmental protection regs. & court rulings DPR's Pyrethroid Reevaluation Work w/ registrants to better define sources & identify potential mitigation Management practices being studied & evaluated e.g., application methods/amounts, wash off from dif. surfaces, lawn irrigation management Urban user outreach projects by DPR, UCIPM & others Industry-led IPM-based pest control services U.S. EPA label changes (e.g., pre-construction termiticide treatments)
Why is Urban Mitigation Such a Challenge? Traditional W.Q. mitigation tools for Ag. not suited for urban setting Impractical? Impossible? How do you effectively control or enforce so many small applications? Still does not take much to be problematic parts per billion or trillion Should we fix a.i. or use pattern? 26
27 Future Mitigation DPR to release new draft S.W. regulations to address urban (& Ag.) W.Q. issues Contains basic requirements to address a variety of urban sources (will likely focus on commercial structural & landscape uses) Formal rulemaking in 2010/2011? Adopted regs. 2011/2012? Other stewardship & regulatory activities
Thank You... Nan Singhasemanon Staff Environmental Scientist/MAA Coordinator Environmental Monitoring Branch Surface Water Protection Program 1001 I St., Sacramento, CA 95812 nsinghasemanon@cdpr.ca.gov (916) 324-4122 28