The chronic toxicity of emamectin benzoate to three marine benthic species using microcosms

The commercial farming of Atlantic salmon, Salmo salar, may require the periodic application of emamectin benzoate (EB) treatments to reduce the effects of biological pests, such as sea lice. As a result, EB is detected in sediments beneath these fish farms at considerable levels. Literature sediment toxicity data for EB for marine benthic species is only available for 10-day sediment toxicity tests, which might be too short to assess field effects. Here, we present a sediment toxicity test to determine 28-day mortality and growth effect concentrations for the non-target polychaete worm Arenicola marina, the crustacean Corophium volutator and the mollusk Cerastoderma edule using a marine microcosm setup. Results indicate that no concentration-dependent increase of mortality and growth rate was apparent to A. marina and C. edule. But for C. volutator, a concentration-dependent increase in mortality was observed, resulting in a calculated 28-d LC50 of 316 μg/kg dry sediment (95% confidence interval: 267–373 μg/kg dry sediment). There were significant effects on C. volutator growth rate at concentrations of 100 μg/kg dry sediment and above (NOEC = 30 μg/kg dry sediment). These observations show that C. volutator is more sensitive to EB than A. marina, which differs from results reported in previous studies. Comparison to the most sensitive NOEC (30 μg/kg dry sediment) found for C. volutator (organisms of 8–11 mm length), shows that the Environmental Quality Standard, derived by the Scottish Environment Protection Agency in 2017 which based on freshwater species data (NOEC = 1.175 μg/kg dry sediment), are relatively strict and is sufficiently protective for the marine species tested in this paper.</p

Dataset underlying the publication Seasonal dynamics of the macrophyte test species Myriophyllum spicatum over two years in experimental ditches for population modelling application in risk assessment

The dataset covers biotic and abiotic data from the aquatic habitat of a population of the sediment-rooted macrophyte Myriophyllum spicatum in the temperate climate region (The Netherlands). The growth of M. spicatum was monitored in 0.2025 m2 plant baskets installed in an experimental ditch. Parameters monitored included biomass (fresh and dry weight), shoot length, seasonal short-term growth rates of shoots, relevant environmental parameters and weather data. This dataset includes the 2-year experimental biotic (macrophyte biomass and growth data) and environmental data (water quality data, sediment data). A second file includes the statistical data. A third file includes the weather data

Use, fate and ecological risks of antibiotics applied in tilapia cage farming in Thailand

The use, environmental fate and ecological risks of antibiotics applied in tilapia cage farming were investigated in the Tha Chin and Mun rivers in Thailand. Information on antibiotic use was collected through interviewing 29 farmers, and the concentrations of the most commonly used antibiotics, oxytetracycline (OTC) and enrofloxacin (ENR), were monitored in river water and sediment samples. Moreover, we assessed the toxicity of OTC and ENR on tropical freshwater invertebrates and performed a risk assessment for aquatic ecosystems. All interviewed tilapia farmers reported to routinely use antibiotics. Peak water concentrations for OTC and ENR were 49 and 1.6 μg/L, respectively. Antibiotics were most frequently detected in sediments with concentrations up to 6908 μg/kg d.w. for OTC, and 2339 μg/kg d.w. for ENR. The results of this study indicate insignificant short-term risks for primary producers and invertebrates, but suggest that the studied aquaculture farms constitute an important source of antibiotic pollution