Optimized Antibiotic Resistance Genes Monitoring Scenarios Promote Sustainability of Urban Water Cycle.

Dissemination of antibiotic resistance genes (ARGs) in urban water bodies has become a significant environmental and health concern. Many approaches based on real-time quantitative PCR (qPCR) have been developed to offer rapid and highly specific detection of ARGs in water environments, but the complicated and time-consuming procedures have hindered their widespread use. Herein, we developed a facile one-step approach for rapid detection of ARGs by leveraging the trans-cleavage activity of Cas12a and recombinase polymerase amplification (RPA). This efficient method matches the sensitivity and specificity of qPCR and requires no complex equipment. The results show a strong correlation between the prevalence of four ARG markers (ARGs: sul1, qnrA-1, mcr-1, and class 1 integrons: intl1) in tap water, human urine, farm wastewater, hospital wastewater, municipal wastewater treatment plants (WWTPs), and proximate natural aquatic ecosystems, indicating the circulation of ARGs within the urban water cycle. Through monitoring the ARG markers in 18 WWTPs in 9 cities across China during both peak and declining stages of the COVID epidemic, we found an increased detection frequency of mcr-1 and qnrA-1 in wastewater during peak periods. The ARG detection method developed in this work may offer a useful tool for promoting a sustainable urban water cycle.

[Environmental Behaviors of Plant Growth Regulators in Soil: A Review].

At present, plant growth regulators play an increasingly important role in global agricultural production. The average growth rate of global sales of plant growth regulators has been above 14% in the past decade. For many years, most plant growth regulators have been considered low-toxicity or slight-toxicity pesticides. However, recent studies have found that many plant growth regulators and their degradation products in the environment are potentially harmful to humans, animals, and plants. As the key factors to control the entering of plant growth regulators into the environment, the environmental behaviors of plant growth regulators in soil could make a significant influence on the risk of plant growth regulators to environmental safety. Therefore, it is critical to investigate the environmental behaviors of plant growth regulators in soil. This study systematically summarizes the environmental behaviors of plant growth regulators in soil from recent research, including the adsorption, desorption, hydrolysis, photolysis, and microbial degradation. Additionally, the factors affecting the environmental behaviors of plant growth regulators in the soil are discussed in detail. Moreover, the future research focus and direction to plant growth regulators are suggested.