Tracking aerosolized mosquito control pesticides in an urban atmosphere.

Guberman VerPloeg, Sarah L., 1994-

Tracking aerosolized mosquito control pesticides in an urban atmosphere.

dc.contributor.advisor	Usenko, Sascha.
dc.creator	Guberman VerPloeg, Sarah L., 1994-
dc.creator.orcid	0000-0001-6312-1895
dc.date.accessioned	2024-07-30T12:41:24Z
dc.date.available	2024-07-30T12:41:24Z
dc.date.created	2023-12
dc.date.issued	2023-12
dc.date.submitted	December 2023
dc.date.updated	2024-07-30T12:41:29Z
dc.description.abstract	Public health authorities release aerosolized pesticides, “adulticides,” directly into the atmosphere to control adult mosquito populations and reduce the threat of diseases. Malathion and permethrin, both known neurotoxins, are the primary adulticides used for mosquito control in urban areas. Malathion and permethrin can undergo chemical degradation via atmospheric oxidants, which are present throughout typical urban atmospheres, especially during peak mosquito season (summer). Despite this, adulticides are routinely used in urban areas without fully understanding how atmospheric processes (oxidation) impact their environmental fate. Chamber-based studies have assessed the oxidation of adulticides for select oxidants. However, few studies have assessed the environmental fate and transport of adulticides within the context of urban-scale (multi- county) mosquito control. Described herein is a study specially designed to investigate the spatial and temporal variation, and aerosol size fraction distribution of adulticide transport and oxidation post-application throughout greater Houston across 3 summers. In 2013, atmospheric concentrations of malathion and permethrin at application sites closely reflected the alternating adulticide treatment schedule. Malaoxon, an oxidation product of malathion, was also frequently detected, indicating significant oxidation. The atmospheric half-life of malathion in Houston was estimated at <12 h, which was significantly shorter than previous estimates. These results raise concerns of health effects and adulticide efficacy since malaoxon is potentially less effective as an adulticide and more toxic to humans. In 2016, malathion, malaoxon, and permethrin were measured throughout the sampling campaign at a downwind site, despite the alternating adulticide treatment schedule. Confirmation from NOAA HYSPLIT backward trajectories indicates the downwind site is influenced by multiple county-level mosquito control programs. This cross-county contamination may impact adulticide effectiveness through development of pesticide resistance in mosquito populations, and highlights the need for collaboration between county-level mosquito control programs. In 2017, aggressive efforts to control mosquito population growth post-Harvey presented a unique opportunity to investigate adulticide oxidation with improved temporal resolution. Preliminary analysis highlights the potential for rapid adulticide oxidation (<2 h half-life) during high ozone events in an urban area. This research can be expanded by measuring adulticide oxidation in the gas phase, and observing the impacts of adulticide oxidation on mosquito control efficacy.
dc.format.mimetype	application/pdf
dc.identifier.uri
dc.identifier.uri	https://hdl.handle.net/2104/12854
dc.language.iso	English
dc.rights.accessrights	No access – contact librarywebmaster@baylor.edu
dc.title	Tracking aerosolized mosquito control pesticides in an urban atmosphere.
dc.type	Thesis
dc.type.material	text
local.embargo.lift	2025-12-01
local.embargo.terms	2025-12-01
thesis.degree.department	Baylor University. Dept. of Environmental Science.
thesis.degree.grantor	Baylor University
thesis.degree.name	Ph.D.
thesis.degree.program	Environmental Science
thesis.degree.school	Baylor University