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Impact and Efficacy of Aerial ULV Application of Permanone 30-30. Research Report. Objectives:. Measure permethrin residue ground deposition Determine permethrin airborne concentration Assess non-target impact using mosquito fish bioassay
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Impact and Efficacy of Aerial ULV Application of Permanone 30-30 Research Report FCCMC Meeting Oct 24, 2006
Objectives: • Measure permethrin residue ground deposition • Determine permethrin airborne concentration • Assess non-target impact using mosquito fish bioassay • Evaluate control efficacy against adult mosquitoes through bioassay • Correlate residue and bioassay FCCMC Meeting Oct 24, 2006
Materials and Methods • Study Site: Panama City Beach • 12 stations (9 treatments and 3 controls) • The 9 treatment stations include 6 open sites and 3 in woodland area • Beach MCD’s helicopter (Helo N91336) equipped with WingmanTM GX and AIMMS-20 (Adapco) was used for the Aerial ULV spray at 150ft attitude. • Residue sample collections: yarn, water and filter paper • Permethrin Analysis -GC with ECD detector FCCMC Meeting Oct 24, 2006
Materials and Methods • Bioassay: caged mosquitoes (+50 female mosquitoes / cage) (Ochlerotatus taeniorhynchus) 12-hrs post-treatment • Bioassay: caged mosquito fish (Gambusia holbrooki) in plastic pans (10/pan). The acute toxicity was checked 1 hr after the spray and the chronic toxicity was assessed daily for 5 days in the same plastic pan (108-hrs post-treatment --worst case scenario) FCCMC Meeting Oct 24, 2006
Result (1) Permethrin Residue on Filter Paper (µg/m2) and (Fish Mortality) FCCMC Meeting Oct 24, 2006
Result (2) Permethrin Residueon Yarn (µg/yarn) and (%Mosquito Mortality) FCCMC Meeting Oct 24, 2006
Discussion Permethrin Residue • Low level permethrin residue (2.14 ppb and 4.36 ppb) was detected in water samples from the fish tank from two separate spray events (6/27/2006 and 7/18/2006) and both samples collected from site 1 • The highest permethrin deposition on filter paper was on site 9 (151µg/m2). That matched up to low residue on yarn (6.0 µg/yarn) indicating it may have the large droplets fall out. In fact that many of higher ground deposition (>90 µg/m2) did not have good mosquito control efficacy • The range of ground deposition was about 37 – 151 µg/m2 • The highest permethrin residue found on yarn was 170 µg/m2 and the range was 3 – 170 µg/m2 • With few exceptions, the residue on yarn reached >40 µg/yarn, the control efficacy was greatly improved. FCCMC Meeting Oct 24, 2006
Discussion (2)fish and mosquito assay • PPB level permethrin residue was detected in tank water samples from two separate spray events on site 1 did not cause fish mortality at higher concentration (4.36 ppb). • There were no indication of acute toxic effect permethrin on fish from field bioassay even with the highest ground deposition (151 µg/m2). • Various fish mortality found during each trial and the reason is unknown or appears not correlated with permethrin concentration • We suspect the stressed fish were picked for the assay in trial 2 and 3 as the control fish mortality increasing. The fact of fish reservoir lost screen enclosure as a result from storm. • Only six stations in three spray evens reached >80% mosquito mortality. The low control efficacy in general a concern and the reasons need to be further investigated. FCCMC Meeting Oct 24, 2006
Acknowledgements The following personnel contributed to this project: • Florida A&M University • C. Brock, T. Quimet, T. Lian, R. Aarons, N. Sickerman, -participation • K. Shaffer and J. Petersen –Provide mosquito pupae • J. Smith, E. Cope and J. Walsh – Provide mosquito rearing room • Beach Mosquito Control Districts • E. Hunter, J. Shehee, Skip, Lee, and Cindy - participation • Florida Department of Agricultural and Consumer Services • Max Feken, James Clauson -participation • Bayer Environmental Science • Peter Connelly -participation, Jing Zhai (consultant) • Adapco, • Bill Reynolds –computer model and spray tech. • Lee County Mosquito Control District • J. Hornby –droplets analysis FCCMC Meeting Oct 24, 2006
Any Questions ? FCCMC Meeting Oct 24, 2006