Impact of agricultural runoff and domestic sewage discharge on the spatial-temporal occurrence of emerging contaminants in an urban stream in São Paulo, Brazil

Comprehensive review of emerging contaminants: Detection technologies, environmental impact, and management strategies

Emerging contaminants (ECs) are a diverse group of unregulated pollutants increasingly present in the environment. These contaminants, including pharmaceuticals, personal care products, endocrine disruptors, and industrial chemicals, can enter the environment through various pathways and persist, accumulating in the food chain and posing risks to ecosystems and human health. This comprehensive review examines the chemical characteristics, sources, and varieties of ECs. It critically evaluates the current understanding of their environmental and health impacts, highlighting recent advancements and challenges in detection and analysis. The review also assesses existing regulations and policies, identifying shortcomings and proposing potential enhancements. ECs pose significant risks to wildlife and ecosystems by disrupting animal hormones, causing genetic alterations that diminish diversity and resilience, and altering soil nutrient dynamics and the physical environment. Furthermore, ECs present increasing risks to human health, including hormonal disruptions, antibiotic resistance, endocrine disruption, neurological effects, carcinogenic effects, and other long-term impacts. To address these critical issues, the review offers recommendations for future research, emphasizing areas requiring further investigation to comprehend the full implications of these contaminants. It also suggests increased funding and support for research, development of advanced detection technologies, establishment of standardized methods, adoption of precautionary regulations, enhanced public awareness and education, cross-sectoral collaboration, and integration of scientific research into policy-making. By implementing these solutions, we can improve our ability to detect, monitor, and manage ECs, reducing environmental and public health risks.

Summary recommendations on "Analytical methods for substances in the Watch List under the Water Framework Directive"

The Watch List (WL) is a monitoring program under the European Water Framework Directive (WFD) to obtain high-quality Union-wide monitoring data on potential water pollutants for which scarce monitoring data or data of insufficient quality are available. The main purpose of the WL data collection is to determine if the substances pose a risk to the aquatic environment at EU level and subsequently to decide whether a threshold, the Environmental Quality Standards (EQS) should be set for them and, potentially to be listed as priority substance in the WFD. The first WL was established in 2015 and contained 10 individual or groups of substances while the 4th WL was launched in 2022. The results of monitoring the substances of the first WL showed that some countries had difficulties to reach an analytical Limit of Quantification (LOQ) below or equal to the Predicted No-Effect Concentrations (PNEC) or EQS. The Joint Research Centre (JRC) of the European Commission (EC) organised a series of workshops to support the EU Member States (MS) and their activities under the WFD. Sharing the knowledge among the Member States on the analytical methods is important to deliver good data quality. The outcome and the discussion engaged with the experts are described in this paper, and in addition a literature review of the most important publications on the analysis of 17-alpha-ethinylestradiol (EE2), amoxicillin, ciprofloxacin, metaflumizone, fipronil, metformin, and guanylurea from the last years is presented.

Integrated water quality dynamics in Wadi Hanifah: Physical, chemical, and biological perspectives

The Wadi Hanifah, a crucial aquatic ecosystem, has unfavorable consequences from natural occurrences and human activities. Recognizing the critical need for sustainable water management, this study provides an in-depth evaluation of wadi water quality. A comprehensive assessment was conducted, analyzing physical properties (temperature, pH, electrical conductivity, turbidity, color, and odor), chemical constituents (nitrogen compounds, ion concentrations, heavy metals), and bacterial diversity. The study found significant temperature fluctuations, particularly in sun-exposed or stagnant water areas. The water exhibited slight alkalinity and variable electrical conductivity and turbidity, indicating differing pollution levels. High ammonia and heavy metal concentrations suggested organic and industrial contamination, respectively. In addition, the prevalent fecal-indicator bacteria pointed to possible sewage or agricultural runoff. The research highlights the complex interplay of natural and anthropogenic factors affecting Wadi Hanifah's water quality. It emphasizes the need for location-specific environmental management strategies focusing on pollution control and conservation to safeguard the wadi's ecological health. This study provides vital insights for effective water resource management in Wadi Hanifah, serving as a model for similar ecosystems.

Atrazine and its degradation products in drinking water source and supply: Risk assessment for environmental and human health in Campinas, Brazil

Atrazine is a broad-spectrum herbicide widely used worldwide to control grassy and broadleaf weeds. Atrazine's popularity is attributable to its cost-effectiveness and reliable performance. Relatedly, it is also an important micropollutant with a potential negative impact on biodiversity and human health. Atrazine has long been regularly detected in several environmental compartments, and its widespread use has resulted in ubiquitous and unpreventable contamination. Among pesticides sold in Brazil, atrazine has remained among the top-ranked active ingredients for the last several years. Thus, this study aimed to evaluate the occurrence of atrazine and three degradation products (hydroxyatrazine, desisopropylatrazine, and desethylatrazine) in surface water (Capivari and Atibaia rivers) and treated water, monthly sampling from two drinking water treatment plants in Campinas (São Paulo, Brazil). An analytical method using solid-phase extraction (SPE) and liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to determine target compounds simultaneously. The method presented instrument quantification limits from 0.5 to 4.0 ng mL^-1 and recovery values from 80 to 112%, with a maximum relative standard deviation of 6%. All analytes had a detection frequency of 100% from 2 to 2744 ng L^-1. Statistical analysis showed no analyte removal after conventional water treatment. Also, the Capivari River showed greater analyte concentration than the Atibaia River. Performed risk assessments according to current Brazilian standards showed no human and environmental health risks. However, other risk assessment approaches may indicate potential risks, advocating for further research and ongoing surveillance.

Transcriptome analysis reveals the mechanisms of hepatic injury caused by long-term environmental exposure to atrazine in juvenile common carp (Cyprinus carpio L.)

Atrazine (ATZ) is the second most commonly used herbicide worldwide, resulting in the pollution of water bodies and affecting the economic benefits of aquaculture. ATZ is known to cause liver damage in the common carp, Cyprinus carpio L., one of the most widely cultivated fish in China, but the underlying mechanisms are poorly understood. In this study, juvenile common carp Cyprinus carpio L. were exposed to three different environmental levels (0.4, 0.8, and 1.2 μg/L) of ATZ for 12 weeks and changes in the liver transcriptomes between the high-dose group and the control group were analyzed. The data showed that different levels of ATZ exposure caused hepatotoxicity in juvenile carp, shown by biochemical parameters and histopathological changes. Comparative transcriptomics showed that high-dose ATZ exposure led to alterations in the expression of various lipid metabolism-related gene changes, including genes associated with metabolic pathways, fatty acid metabolism, and fatty acid elongation. Furthermore, a connection network analysis of the top 100 differentially expressed genes (DEGs) showed a variety of associations between high-dose ATZ-induced liver damage and the principal DEGs, indicating the complexity of hepatotoxicity induced by ATZ. In conclusion, the molecular mechanisms underlying ATZ-triggered hepatotoxicity in juvenile carp are primarily related to impaired lipid metabolism.

Spatial-temporal occurrence of contaminants of emerging concern in urban rivers in southern Brazil

The widespread use and misuse of antibiotics and pesticides has been linked with several risks to the environment and human health. In the present report, the results of the monitoring of 64 pharmaceuticals and 134 pesticides occurrence in an urban river in Southern Brazil are presented and discussed. Sampling campaigns have covered the period 2016-2018. The identification and determination of the analytes were achieved by high-resolution mass spectrometry. The data were analyzed using chemometric tools to obtain spatial-temporal models. Toxicological evaluation was achieved using acute toxicity (zebrafish standardized protocol), and determination of risk quotient. Within the 198 analytes included in the targeted analysis method for surface water, 33 were identified in an urban river during 2 years of monitoring, being 20 pharmaceuticals and 13 pesticides. Using high-resolution mass spectrometry, a suspect screening approach was established in an un-target analysis. The evaluation was carried out using a data bank built from consumption data of drugs and pesticides, in the metropolitan region of Porto Alegre - RS and their respective metabolites. The suspect screening analysis done with a data bank with more than 1450 compounds results in 27 suspect findings. The target analysis results showed a continuous prevalence of non-steroidal anti-inflammatories, analgesics, antipyretics, beta-blockers, corticoids, and antibiotics. Regarding the pesticides, the main classes were fungicides, especially those from triazol and strobilurin classes.