title: Mosquito control insecticides: a probabilistic ecological risk assessment on drift exposures of naled, dichlorvos (naled metabolite) and permethrin to adult butterflies.
abstract: A comprehensive probabilistic terrestrial ecological risk assessment (ERA) was conducted to characterize the potential risk of mosquito control insecticide (i.e., naled, it's metabolite dichlorvos, and permethrin) usage to adult butterflies in south Florida by comparing the probability distributions of environmental exposure concentrations following actual mosquito control applications at labeled rates from ten field monitoring studies with the probability distributions of butterfly species response (effects) data from our laboratory acute toxicity studies. The overlap of these distributions was used as a measure of risk to butterflies. The long-term viability (survival) of adult butterflies, following topical (thorax/wings) exposures was the environmental value we wanted to protect. Laboratory acute toxicity studies (24-h LD50) included topical exposures (thorax and wings) to five adult butterfly species and preparation of species sensitivity distributions (SSDs). The ERA indicated that the assessment endpoint of protection, of at least 90% of the species, 90% of the time (or the 10th percentile from the acute SSDs) from acute naled and permethrin exposures, is most likely not occurring when considering topical exposures to adults. Although the surface areas for adulticide exposures are greater for the wings, exposures to the thorax provide the highest potential for risk (i.e., SSD 10th percentile is lowest) for adult butterflies. Dichlorvos appeared to present no risk. The results of this ERA can be applied to other areas of the world, where these insecticides are used and where butterflies may be exposed. Since there are other sources (e.g., agriculture) of pesticides in the environment, where butterfly exposures will occur, the ERA may under-estimate the potential risks under real-world conditions.
authors.affiliation: Ecotoxicology and Risk Assessment, Southeast Environmental Research Center, Department of Earth and Environmental Sciences, Florida International University, Biscayne Bay Campus, 3000 N.E. 151st Street, N. Miami, FL 33181, United States; Department of Environmental Sciences, Institute of Environmental Sustainability, Loyola University Chicago, 1032 W. Sheridan Rd, Chicago, IL 60626, United States.
authors.forename: T C
authors.initials: TC
authors.lastname: Hoang
authors.affiliation: Ecotoxicology and Risk Assessment, Southeast Environmental Research Center, Department of Earth and Environmental Sciences, Florida International University, Biscayne Bay Campus, 3000 N.E. 151st Street, N. Miami, FL 33181, United States. Electronic address: randg@fiu.edu.
authors.forename: G M
authors.initials: GM
authors.lastname: Rand
mesh_terms: D000818:Animals; D002080:Butterflies / Q000187:drug effects*; D004006:Dichlorvos / Q000633:toxicity; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D004784:Environmental Monitoring; D005431:Florida; D007306:Insecticides / Q000633:toxicity*; D007928:Lethal Dose 50; D009032:Mosquito Control / Q000379:methods*; D009267:Naled / Q000633:toxicity; D026023:Permethrin / Q000633:toxicity; D018570:Risk Assessment / Q000379:methods
chemical_list: D007306:Insecticides; D026023:Permethrin; D004006:Dichlorvos; D009267:Naled
keywords: Butterflies; Dichlorvos; Ecological risk assessment; Mosquito control insecticides; Naled; Permethrin