Ecotoxicological assessment of sanitary sewer overflows and rainfall dynamics offers insights into conditions for potential adverse ecological outcomes.

Sewer overflows are an environmental concern due to their potential to introduce contaminants that can adversely affect downstream aquatic ecosystems. As these overflows can occur during rainfall events, the influence of rainwater ingress from inflow and infiltration on raw untreated wastewater (influent) within the sewer is a critical factor influencing the dilution and toxicity of the contaminants. The Vineyard sewer carrier in the greater city of Sydney, Australia, was selected for an ecotoxicological investigation of a sanitary (separate from stormwater) sewerage system and a wet-weather overflow (WWO).

The influence of salinity on the chronic toxicity of shale gas flowback wastewater to freshwater organisms.

The potential environmental risk associated with flowback waters generated during hydraulic fracturing of target shale gas formations needs to be assessed to enable management decisions and actions that prevent adverse impacts on aquatic ecosystems. Using direct toxicity assessment (DTA), we determined that the shale gas flowback wastewater (FWW) from two exploration wells (Tanumbirini-1 and Kyalla 117 N2) in the Beetaloo Sub-basin, Northern Territory, Australia were chronically toxic to eight freshwater biota. Salinity in the respective FWWs contributed 16% and 55% of the chronic toxicity at the 50% effect level.

Combined toxicity of therapeutic pharmaceuticals to duckweed, Lemna minor.

Pharmaceuticals, which are designed to be biologically active at low concentrations, are found in surface waters, meaning aquatic organisms can be exposed to complex mixtures of pharmaceuticals. In this study, the adverse effects of four pharmaceuticals, 17α-ethynylestradiol (synthetic estrogen), methotrexate (anticancer drug), diclofenac (nonsteroidal anti-inflammatory drug) and fluoxetine (antidepressant), and their binary mixtures at mg/L concentrations were assessed using the 7-day Lemna minor test, with both apical and biochemical markers evaluated. The studied biochemical markers included chlorophyll a, chlorophyll b, carotenoids and oxidative stress enzymes catalase, glutathione-S-transferase and glutathione reductase, with effects compared to solvent controls.

Aquatic Phytotoxicity to Lemna minor of Three Commonly Used Drugs of Addiction in Australia.

The manufacturing and consumption of drugs of addiction has increased globally and their widespread occurrence in the environment is an emerging concern. This study evaluated the phytotoxicity of three compounds: methamphetamine, codeine and morphine; commonly reported in Australian urban water, to the aquatic plant Lemna minor under controlled conditions. L.

Effects of copper on the survival, hatching, and reproduction of a pulmonate snail (Physa acuta).

Acute and chronic bioassays provide essential basis for establishment of environmental quality standards. The effects of Cu on a pulmonate snail, Physa acuta, were investigated at a number of sublethal and lethal endpoints. Cu exposure suppressed movement and triggered an escape response in P.

Derivation of water quality guidelines for priority pharmaceuticals.

Pharmaceuticals can enter freshwater and affect aquatic ecosystem health. Although toxicity tests have been carried out for the commonly used pharmaceuticals, evidence-based water quality guidelines have not been derived. High-reliability water quality guideline values have been derived for 4 pharmaceuticals-carbamazepine, diclofenac, fluoxetine, and propranolol-in freshwaters using a Burr type III distribution applied to species sensitivity distributions of chronic toxicity data.