Bifenthrin Causes Toxicity in Urban Stormwater Wetlands: Field and Laboratory Assessment Using Austrochiltonia (Amphipoda)

Abstract

Stormwater wetlands are engineered to accumulate sediment and pollutants from stormwater and provide environmental value to urban environments. Therefore, contaminated sediment risks causing toxicity to aquatic fauna. This research identifies contaminants of concern in urban wetland sediments by assessing sediment toxicity using the amphipod Austrochiltonia subtenuis. Sediments from 98 wetlands were analyzed for contaminants, and laboratory bioassays were performed with A. subtenuis. Wild Austrochiltonia spp. were also collected from wetlands to assess field populations. Random forest modeling was used to identify the most important variables predicting survival, growth, and field absence of Austrochiltonia spp. Bifenthrin was the most frequently detected pesticide and also the most important predictor of Austrochiltonia spp. responses. Copper, permethrin, chromium, triclosan, and lead were also important. The median lethal effect concentration (LC50) of bifenthrin to laboratory-based A. subtenuis (1.09 (±0.08) μg/gOC) exposed to wetland sediments was supported by a bifenthrin-spiked sediment experiment, indicating A. subtenuis is a suitable test species. Furthermore, Austrochiltonia spp. were absent from all sites that exceeded the calculated bifenthrin LC50, demonstrating the impact of this contaminant on wild populations. This research demonstrates the sensitivity of Austrochiltonia spp. to urban sediment contamination and identifies bifenthrin as a contaminant of concern in urban wetlands.

Metabolomic Profiles of a Midge (Procladius villosimanus, Kieffer) Are Associated with Sediment Contamination in Urban Wetlands

“…Aside from the general metal and hydrocarbon contamination, the widespread occurrence and elevated concentration of bifenthrin and triclosan are emerging concerns. Studies in Australia and elsewhere have reported environmental impacts of bifenthrin and other synthetic pyrethroids at similar concentrations to those observed here [ 36 , 37 , 38 , 39 , 40 ]. Triclosan, an antimicrobial used in many household products, has also recently been highlighted as a risk to environmental and human health [ 41 , 42 ].…”

“…Sediments were analyzed for metals, pesticides, total organic carbon, petroleum hydrocarbons, polycyclic aromatic hydrocarbons (PAHs). Experimental details for sediment analysis have been published previously [ 34 , 35 , 36 ]. Briefly, University of Melbourne Chemistry Department analyzed the sediments for organic contaminants by GC-MS, including personal care products and selected pesticides.…”

Unintentional exposure to terrestrial pesticides drives widespread and predictable evolution of resistance in freshwater crustaceans

“…Pyrethroids in surface waters and associated toxicity have been reported in many regions of the United States (Hintzen, Lydy, & Belden, ; Kuivila et al., ; Rogers et al., ). Internationally, they have been found in water bodies at concentrations of ecotoxicological concern in several South American countries (Hunt et al., ), England (Long, House, Parker, & Rae, ), Spain (Feo, Ginebreda, Eljarrat, & Barceló, ), China (Mehler, Li, Lydy, & You, ), and Australia (Jeppe et al., ). Additionally, while most studies documenting aquatic risk of pyrethroids in the United States have generally relied upon H. azteca , work elsewhere has reported toxicity to Chironomus dilutus (Mehler et al., ) and the amphipod, Austrochiltonia subtenuis (Jeppe et al., ).…”

“…Internationally, they have been found in water bodies at concentrations of ecotoxicological concern in several South American countries (Hunt et al., ), England (Long, House, Parker, & Rae, ), Spain (Feo, Ginebreda, Eljarrat, & Barceló, ), China (Mehler, Li, Lydy, & You, ), and Australia (Jeppe et al., ). Additionally, while most studies documenting aquatic risk of pyrethroids in the United States have generally relied upon H. azteca , work elsewhere has reported toxicity to Chironomus dilutus (Mehler et al., ) and the amphipod, Austrochiltonia subtenuis (Jeppe et al., ). Thus, it is possible, and even likely, that other species are exposed to the same pyrethroid‐related selective pressures we documented in H. azteca .…”

Using conservation behavior to manage ecological traps for a threatened freshwater fish

“…Levels of at least some organic pollutants likely differ between reference and stormwater sites, as the former receive water from direct rainfall and local runoff from adjacent paddocks, whereas runoff into the latter is predominantly from high-density residential and industrial areas. As an example, nearby sites in the upstream catchment have sediment concentrations of the insecticide bifenthrin above those that cause toxicity to crustacea (amphipods; Jeppe et al 2017). This could reduce zooplankton densities (predominantly crustacea) within contaminated sites, with flow-on effects to fish growth, reproduction, and survival.…”