Evaluating the Effects of Diet on the Sensitivity of Hyalella azteca to an "Eco-friendly" Deicing Agent.

Salting of roadways contaminates local waterways via snowmelt and precipitation runoff, eliciting various toxicological impacts on aquatic ecosystems. Recently, "eco-friendly" deicing alternatives have been introduced in hopes of mitigating environmental impacts of deicing agents, while maintaining human safety. These "eco-friendly" alternatives may pose their own set of environmental concerns that require further study. While the potential toxicity of road salts has been evaluated for various aquatic species, the environmental factors that may influence this toxicity are less understood; and for emerging deicing alternatives, there is a lack of literature documenting these potential implications. For aquatic organisms, the highest exposure to road salts may coincide with reduced food availability, namely during the winter months. The present study evaluates the effect of a conditioning diet on the sensitivity of adult Hyalella azteca to an "eco-friendly"-labeled beet deicer (Snow Joe MELT Beet-IT). Various conditioning diets were examined, including TetraMinTM, TetraMin and diatom (Thalassiosira weissflogii) combinations, and TetraMin and conditioned Acer sacharum leaves. For each diet type, 48- and 96-h water-only toxicity bioassays were conducted with adult H. azteca. These results were compared to organisms which experienced a 96-h starvation period prior to exposure and culture organisms. Diet types representing excess quality and quantity of food significantly decreased the toxicity of beet deicer to the organisms. However, starvation likely increases the toxicity of road salts to H. azteca. Therefore, the quantity and quality of food available to H. azteca may influence their sensitivity to deicing agents. Environ Toxicol Chem 2024;00:1-8. © 2024 SETAC.

Alternating water sources to minimize contaminant accumulation in food plants from treated wastewater irrigation.

The use of treated wastewater (TWW) for agricultural irrigation is a critical measure in advancing sustainable water management and agricultural production. However, TWW irrigation in agriculture serves as a conduit to introduce many contaminants of emerging concern (CECs) into the soil-plant-food continuum, posing potential environmental and human health risks. Currently, there are few practical options to mitigate the potential risk while promoting the safe reuse of TWW. In this greenhouse study, the accumulation of 11 commonly occurring CECs was evaluated in three vegetables (radish, lettuce, and tomato) subjected to two different irrigation schemes: whole-season irrigation with CEC-spiked water (FULL), and half-season irrigation with CEC-spiked water, followed by irrigation with clean water for the remaining season (HALF). Significant decreases (57.0-99.8 %, p < 0.05) in the accumulation of meprobamate, carbamazepine, PFBS, PFBA, and PFHxA in edible tissues were found for the HALF treatment with the alternating irrigation scheme. The CEC accumulation reduction was attributed to reduced chemical input, soil degradation, plant metabolism, and plant growth dilution. The structural equation modeling showed that this mitigation strategy was particularly effective for CECs with a high bioaccumulation potential and short half-life in soil, while less effective for those that are more persistent. The study findings demonstrate the effectiveness of this simple and on-farm applicable management strategy that can be used to minimize the potential contamination of food crops from the use of TWW and other marginal water sources in agriculture, while promoting safe reuse and contributing to environmental sustainability.

Does Activated Carbon Used for Soil Remediation Impact Eisenia fetida?

Because granular activated carbon can sequester organic pollutants, a potential strategy for reducing the bioavailability of organic contaminants in soil is through its application to the soil's surface. It is well understood that activated carbon is effective in the remediation of air, water, sediment, and soil, but less information is available on the potential toxicity of activated carbon to native wildlife following in situ remedial applications. Several studies have evaluated the effects of activated carbon on aquatic species; however, less is known about its toxicity to terrestrial species. The present study aimed to evaluate the potential lethal and sublethal effects of activated carbon on adult and juvenile Eisenia fetida, which are earthworms in the family Lumbricidae. The percentage of mortality, initial weight, and pre- and postdepuration weights of the worms were observed following exposure to a range of activated carbon concentrations, from 0.5% to 10% based on the soil's wet weight. These concentrations exceeded the 2%-4% activated carbon typically applied in the field. Activated carbon had no statistically significant effects on E. fetida survival; however, significant although inconsistent effects were observed on earthworm biomass. Although some statistical significance in biomass was observed, the biological significance of these effects is unclear. Overall, the concentrations of activated carbon applied in the field for soil remediation are unlikely to impact earthworm survival, although further testing, specifically on potential sublethal toxic effects, is required. Environ Toxicol Chem 2023;42:1420-1430. © 2023 SETAC.

Adrenocortical development, maintenance, and disease.

The adrenal gland controls a plethora of crucial physiological functions, and dysfunction is associated with severe morbidity. Because of the vital importance of appropriate adrenal function, the development and function of the gland have been intensively studied, and these investigations have revealed fascinating developmental origins and a remarkable remodeling and regenerative capacity in the adult. This chapter, focusing on the adrenal cortex, will describe our current understanding of the development and maintenance of the adrenal gland, which has been advanced over recent years by the use of sophisticated genetic models in the study of both normal function and disease. This work has shed light on the transcriptional networks and signaling pathways involved in development and maintenance of the gland and in its pathology; these are discussed in the light of the wealth of physiological information gathered in studies of human and rodent adrenal development and function.

Treatment of a sole abscess in an Asian elephant (Elephas maximus) using regional digital intravenous perfusion.

Regional digital i.v. perfusion was used to treat a severe sole abscess associated with a wire foreign body in a 19-yr-old female Asian elephant (Elephas maximus) housed at the Paris Zoo. The cow presented with acute right forelimb lameness and swelling that persisted despite 4 days of anti-inflammatory therapy. Under anesthesia, a 10- x 0.5- x 0.5-cm wire was extracted from the sole of the right foot. There was a 2-cm-deep, 7-cm-diameter abscess pocket that was subsequently debrided. Regional digital i.v. perfusion was performed and repeated 15 days later, using cefoxitin and gentamicin on both occasions. Between treatments, the cow received trimethoprim-sulfamethoxazole and phenylbutazone orally. Within 2 days of administering anesthesia and the first perfusion treatment, the lameness improved dramatically. When phenylbutazone was discontinued 1 wk after the first treatment, the lameness had completely resolved. At the second treatment, there was no evidence of further soft tissue infection, and the abscess pocket had resolved.