Activity

The essential cause of phosphorus scarcity and phosphorus-induced risks, i.e. phosphorus dilemma, mainly lies in current low phosphorus flow efficiency (PFE) in agricultural systems. Improving PFE largely depends on secondary phosphorus retention along the phosphorus flow chain from phosphate mining to terrestrial agricultural systems, to aquatic systems, and ultimately to seabed deposition. Our review found that aquatic systems will have the opportunity and growing capacity to retain seaward secondary phosphorus carried by the runoff, due to its location between land and water systems, its ability of converting secondary phosphorus from both land and aquatic systems into aquatic products, and its rapid expansion with low PFE. However, a knowledge gap exists in secondary phosphorus retention in aquatic systems compared to in terrestrial systems. Although the phosphorus retention literature continues to grow in environmental and agricultural & biological sciences, only 8.8% of the documents are related to aquatic systems with few quantification studies. Based on the literature with phosphorus retention quantification since 1979, we divided the reported phosphorus interceptors into abiotic and biotic groups, further into 7 categories and more subcategories. By 2020, eight categories of interceptors had been reported, increased from only one interceptor in 1979. However, most of them focused on wetlands, only a few studies on aquatic organisms which concentrated in 8 countries before 2000. Thus, it is urgent to emphasize aquatic systems’ secondary phosphorus retention capacity and its systemic benefits for a sustainable phosphorus use.The persistent organic pollutants (POPs) are environmentally stable and highly toxic chemicals that accumulate in living adipose tissue and have a very destructive effect on aquatic ecosystems. To analyze the evolution of the concentration and prevalence of POPs such as α-HCH, β-HCH, γ-HCH, ∑-HCH, Heptachlor, Aldrin, p,p’-DDE, p,p’-DDT, ∑-DDT, and ∑-OCP in water resources, a search between January 01, 1970, to February 10, 2020, was followed using a systematic review and meta-analysis prevalence. Among the 2306 explored articles in the reconnaissance step, 311 articles with 5315 exemplars, 56 countries, and 4 types of water were included in the meta-analysis study. Among all studied POPs, the concentration of p,p’-DDT in water resources was the highest, especially in drinking water resources. The overall rank order based on the concentration and prevalence of POPs were surface water > drinking water > seawater > groundwater. check details To identify POPs-contaminated areas, the distance from the mean relative to their distribution was considered. The most to the least polluted areas included South Africa, India, Turkey, Pakistan, Canada, Hong Kong, and China. The highest carcinogenic risk was observed for β-HCH (Turkey and China), followed by α-HCH (Mexico). The highest non-carcinogenic risk was identified for Aldrin (all analyzed countries), followed by Dieldrin (Turkey) and γ-HCH (Mexico). The Monte Carlo analysis (under the assumption that γ-HCH has a normal distribution), the mean obtained was 8.22E-07 for children and 3.83E-07 for adults. This is in accordance with the standard risk assessment approach. In terms of percentiles, the Monte-Carlo approach indicates that 75% of child population is under the 1.07E-06 risk and 95% of adults under 7.35E-06.There is a growing concern on the fate and the consequent ecological or health risks of antibiotics and antibiotic resistance genes (ARGs) in natural or artificial water environment. The effluent of wastewater treatment plants (WWTPs) has been reported to be an important source of antibiotics and ARGs in the environment. WWTP effluent could be discharged into surface water bodies or recycled, either of which could lead to different exposure risks. The impact of WWTP effluents on the levels of antibiotics and ARGs in effluent-receiving water bodies and the removal efficiency of antibiotics and ARGs in reclaimed wastewater treatment plants (RWTPs) were seldom simultaneously investigated. Thus, in this study, we investigated the occurrence of antibiotics and ARGs in four WWTP effluents, and their downstream effluent-receiving water bodies and RWTPs in seasons of low-water-level. The total concentrations of ofloxacin, norfloxacin, ciprofloxacin, roxithromycin, azithromycin, erythromycin, tetracycline, oxytetracycline, chlortetracycline, and sulfamethoxazole in the secondary effluents were 1441.6-4917.6 ng L-1. Ofloxacin had the highest concentration. The absolute and relative abundances of total ARGs (qnrD, qnrS, ermA, ermB, tetA, tetQ, sul1, and sul2) in the secondary effluents were 103-104 copies mL-1 and 10-4-10-2 ARG/16S rRNA. Sul1 and sul2 were the major species with the highest detection frequencies and levels. In most cases, WWTP effluents were not the major contributors to the levels and species of antibiotics and ARGs in the surface water bodies. Four RWTPs removed 43.5-98.9% of antibiotics and – 0.19-2.91 log of ARGs. Antibiotics and ARGs increased in chlorination, ozonation and filtration units. Antibiotics had significantly positive correlations with ARGs, biological oxygen demands, total phosphorus, total nitrogen, and ammonia nitrogen in the four effluent-receiving water bodies. In RWTPs, the total concentrations of antibiotics showed a significant positive correlation with the total abundance of ARGs.Coral reefs are impacted by a variety of anthropogenic stressors including inputs of chemical contaminants. Although data is currently limited, sunscreens containing ultraviolet (UV) filters have recently been suggested as an emerging class of chemical contaminants. To provide further data on the toxicity of the UV filter oxybenzone (benzophenone-3 or BP-3) to corals, we conducted three independent acute toxicity tests exposing the colonial stony coral Galaxea fascicularis to BP-3 (0.31 to 10 mg/L nominal concentrations). Assessments included daily analytical verification of the exposure concentrations, calculation of the lethal concentration to result in 50% mortality (LC50) and numerous biological endpoints to further investigate the potential impact to both the coral and symbiont. LC50s for the three tests were similar and averaged 6.53 ± 0.47 mg/L nominal concentration BP-3 (4.45 mg/L measured dissolved BP-3). BP-3 did not initiate coral bleaching or show a significant loss of symbionts from the coral tissue in this species as reductions in measurements used for bleaching (i.