First national-scale reconnaissance of neonicotinoid insecticides in streams across the USA

Abstract

Environmental context Neonicotinoids are under increased scrutiny because they have been implicated in pollinator declines and, more recently, as potential aquatic toxicants. Nevertheless, there is currently little information on concentrations of multiple neonicotinoids in surface water. This paper presents a summary of concentrations of six neonicotinoids in streams from across the United States in both urban and agricultural areas. These environmental data are important in determining the potential risk of neonicotinoids to non-target aquatic and terrestrial organisms. Abstract To better understand the fate and transport of neonicotinoid insecticides, water samples were collected from streams across the United States. In a nationwide study, at least one neonicotinoid was detected in 53% of the samples collected, with imidacloprid detected most frequently (37%), followed by clothianidin (24%), thiamethoxam (21%), dinotefuran (13%), acetamiprid (3%) and thiacloprid (0%). Clothianidin and thiamethoxam concentrations were positively related to the percentage of the land use in cultivated crop production and imidacloprid concentrations were positively related to the percentage of urban area within the basin. Additional sampling was also conducted in targeted research areas to complement these national-scale results, including determining: (1) neonicotinoid concentrations during elevated flow conditions in an intensely agricultural region; (2) temporal patterns of neonicotinoids in heavily urbanised basins; (3) neonicotinoid concentrations in agricultural basins in a nationally important ecosystem; and (4) in-stream transport of neonicotinoids near a wastewater treatment plant. Across all study areas, at least one neonicotinoid was detected in 63% of the 48 streams sampled.

Pesticides from the EU First and Second Watch Lists in the Water Environment

“…The Regulation provides two indicative analytical methods for each pesticide or group of pesticides: 1) liquid chromatography tandem mass spectrometry (LC‐MS/MS); and 2) gas chromatography‐mass spectrometry (GC‐MS) with solid‐phase extraction (SPE) or liquid‐liquid extraction (LLE) . The LC‐MS/MS method for determining pesticide concentrations in water samples was applied in countries such as: Germany, Canada, Switzerland, USA, Greece, Poland, and France . The GC‐MS or GC‐MS/MS methods were used in: China, Spain, Japan, Canada, and Burkina Faso to determine pesticides in water.…”

“…A mass balance showed an insignificant removal of imidacloprid and limited removal of acetamiprid, whereas in the wetland no removal of imidacloprid or acetamiprid was observed . To obtain the first nationwide data set on neonicotinoids, 38 streams across 24 US states and Puerto Rico were sampled once between November 2012 and June 2014 . These streams were specifically selected owing to a wide range of contaminant sources within their watersheds (e.g., agricultural and urban sources) or as biological reference sites.…”

An update of the Worldwide Integrated Assessment (WIA) on systemic insecticides. Part 1: new molecules, metabolism, fate, and transport

“…Eight out of the 10 most frequently detected chemicals were pesticides, including one metabolite of fipronil (desulfinylfipronil, 0.1-10 ng/L), which was detected at 84% of the sites, whereas fipronil parent compound was found in 45% of sites at concentrations in the range 7-110 ng/L. Among the neonicotinoids detected, imidacloprid was present in 37% of sites (5-100 ng/L), clothianidin in 24% (3-70 ng/L), dinotefuran in 13% (5-110 ng/L), and acetamiprid only at one site (30 ng/L) (Bradley et al 2017) and at least one neonicotinoid in 53% of the water samples collected from streams (Hladik et al 2014;Hladik and Kolpin 2016). Waterborne levels of clothianidin and thiamethoxam residues were correlated to the percentage of crop land in the regions surveyed, whereas imidacloprid levels were related to the percentage of urban area within the basin (Hladik and Kolpin 2016).…”

“…Among the neonicotinoids detected, imidacloprid was present in 37% of sites (5-100 ng/L), clothianidin in 24% (3-70 ng/L), dinotefuran in 13% (5-110 ng/L), and acetamiprid only at one site (30 ng/L) (Bradley et al 2017) and at least one neonicotinoid in 53% of the water samples collected from streams (Hladik et al 2014;Hladik and Kolpin 2016). Waterborne levels of clothianidin and thiamethoxam residues were correlated to the percentage of crop land in the regions surveyed, whereas imidacloprid levels were related to the percentage of urban area within the basin (Hladik and Kolpin 2016). In five urban creeks that discharge into a brackish marsh area of San Francisco Bay, peak concentrations of insecticides were 9.9 ng/L (bifenthrin), 27.4 ng/L (fipronil), 11.9 ng/L (fipronil sulfone), 1462 ng/L (imidacloprid), and 4.0 ng/L (chlorpyrifos) (Weston et al 2015).…”

Modeling the effects of thiamethoxam on Midwestern farm ponds and emergent wetlands

“…An additional ecological concern for neonicotinoids, including thiamethoxam, is leaching into nearby surface waters (Anderson et al 2015). Concentrations of thiamethoxam ranging from 11 to 73 ng/L have been reported for the Missouri River in Nebraska and selected rivers in Iowa (Hladik and Kolpin 2015). Ugurlu et al (2015) demonstrated the toxic effects (a 96-h LC50 of 3.75 mg/L) for amphipods exposed to thiamethoxam.…”