Environmental Quality Standards Research Articles

Landfill leachate treatment process is transforming and releasing banned per- and polyfluoroalkyl substances to UK water

Landfills are a known source of PFAS pollution. Many have environmental permits allowing the discharge of treated leachate to controlled waters. In this article we compared leachate data for 17 PFAS from 17 different landfill sites across the UK. The results show that the landfill leachate treatment process (designed to improve water quality) is generating the banned PFAS; PFOA and PFOS. Approximately 80% of locations tested showed an increase in PFOS, with an increase of 1,335% in one sample. The highest concentrations of PFOS and PFOA in treated leachate were 2,460 ng L−1 and 26,900 ng L−1, respectively. When compared against the environmental quality standard of 0.65 ng L−1 for PFOS this leachate could pose a significant concern. Landfill leachate treatment has proven effective for a wide range of different pollutants, but this research shows in several instances that it is not appropriate for PFAS remediation.

Evaluating the impact of residual low chlorine concentration on phytoplankton communities by flow cytometry

Chlorination is widely used to prevent biological fouling in power station cooling water systems. It may impact non-target organisms both within the cooling system and after discharge (primary and secondary entrainment). However, there is a lack of data on the impacts of the low chlorine concentrations that occur in the discharged plume on marine phytoplankton community structure and function.We examine the impacts on natural phytoplankton communities of single and multiple exposures to chlorination at concentrations between 0.02 and 0.1 mg/L total residual oxidants (TRO). Low-level chlorination causes limited changes in diversity and has no impact on total biomass. However, changes in size structure and functional diversity quantified using flow cytometry do show a reduction in smaller cells, particularly eukaryote picophytoplankton.These impacts are not detectable using chlorophyll a concentration alone, so flow cytometry provides important additional information over more standard ecotoxicological methods.The effects are likely to be localised in the vicinity of the discharges (mixing zone) where the environmental quality standard (EQS) of 10 μg/L for chlorine is exceeded, but impacts on coastal food webs and biogeochemical cycles should be further evaluated.

Effect of tunnel wash water treatment processes on trace elements, organic micropollutants, and biological effects

Tunnel wash water (TWW) contains high levels of trace elements and organic micropollutants, especially in the dissolved fraction. Discharge poses significant environmental risks. This field study aimed at improving conventional sedimentation treatment by addition of novel secondary treatments: bag filtration, ceramic microfiltration, or granular activated carbon (GAC) filtration. Removal of nine trace elements, 16 polycyclic aromatic hydrocarbons (PAHs), 38 per- and polyfluoroalkyl substances (PFASs), seven benzothiazoles (BTHs), seven benzotriazoles (BTRs), five bisphenols (BPs), and five benzophenones was investigated. Primary sedimentation significantly reduced particles and associated contaminants, achieving over 73 % average removal for trace elements, 65 % for PAHs, and 71 % for PFASs. Subsequent GAC removed over 70 % of dissolved Cr, Cu, Pb, and Zn and over 92 % of dissolved PFASs, BTHs, BTRs, and BPs, including several persistent, mobile and toxic compounds. Following GAC filtration, Cr, Ni, Pb, anthracene, fluoranthene, perfluorooctanesulfonic acid, and bisphenol-A were below environmental quality standards (EQS). GAC consistently reduced responses in in vitro bioassays with endpoints activation of the aryl hydrocarbon receptor, oxidative stress response, and neurotoxicity below effect-based trigger values for surface water. GAC filtration is thus recommended for future TWW treatment. Assessing water quality remains a challenging task due to lack of EQSs for many chemicals.

Pengaruh Waktu Aerasi terhadap Peningkatan Efisiensi Penghilangan Amonia di Air Lindi pada Sistem Ammonia Stripper

Talang Gulo Final Disposal Site (FDS) has a Leachate Treatment Plant (LTP) equipped with denitrification and nitrification facilities which function to reduce the concentration of ammonia (NH3) in leachate according to predetermined environmental quality standards. Research samples were taken in the form of leachate using the grab sampling method in accordance with SNI 6989.59:2008. The results of the research showed that the aeration time for the ammonia stripper of 3 hours, 6 hours and 12 hours both gave the highest value for the ammonia stripper efficiency percentage variable. The highest ammonia removal efficiency is aeration time of 12 hours. However, if we look at the operating efficiency of the ammonia stripper, the removal of ammonia by using an aeration time of 12 hours does not provide a significant improvement when compared to a treatment with an aeration time of 6 hours. This means that the operating time is 6 hours faster, the 6 hour variation can provide an ammonia removal efficiency of more than 90%

First full-scale application of barium carbonate as an effective dispersed alkaline substrate for sulfate removal from acid mine drainage

A full-scale passive treatment plant using barium carbonate (BaCO3), the mineral witherite, as a Dispersed Alkaline Substrate (DAS) for strongly contaminated acid mine drainage was implemented for the first time globally at Mina Concepción, located in the Iberian Pyrite Belt (SW Spain). The plant was monitored over a 105-day period, covering the wettest months of the hydrological year and with a mean flow around 4 L s−1. The AMD treated in the plant exhibits a high strength, with an average sulfate concentration around 1500 mg L−1 and net acidity close to 1000 mg L−1 as CaCO₃ equivalent. According to the above, the loading rate for SO4 and Fe was around 400 and 80 kg day−1, respectively. The treatment process produced an alkaline effluent with low metal content. Nearly complete removal of most metal(loid)s was achieved, with significant sulfate decrease to below 500 mg L−1 in the alkaline outflow of the barium carbonate tank. Barium carbonate demonstrated superior performance compared to magnesia, particularly in enhancing alkalinity and lowering net acidity and concentrations of sulfate and manganese. The high efficiency attained by the plant after the barium carbonate treatment is evidenced by compliance with environmental water quality standards for most contaminants.

Toxicokinetic of perfluorinated compounds - A study of liver sequestration in Baltic cod (Gadus morhua callarias) and human dietary exposure

This study assessed the concentrations and temporal trends of perfluorinated compounds (PFCs) in the muscle and liver tissues of Baltic cod (Gadus morhua) from 2017 to 2023. The Environmental Quality Standard (EQS) for biota and the Estimated Weekly Intake (EWI) for human consumers were calculated to evaluate potential health risks associated with PFC exposure. Significant variations in PFC concentrations were observed across different compounds and sampling years. Perfluorooctanoic acid (PFOA) had a mean concentration ranging from 0.03 ng g⁻1 wet weight (ww) to 0.17 ng g⁻1 ww (mean: 0.093 ng g⁻1 ww), while perfluorononanoic acid (PFNA) ranged from 0.05 ng g⁻1 ww to 0.97 ng g⁻1 ww (mean: 0.46 ng g⁻1 ww). Perfluorooctane sulfonate (PFOS) demonstrated mean concentrations between 1.98 ng g⁻1 ww and 9.03 ng g⁻1 ww (mean: 4.78 ng g⁻1 ww). PFOSA exhibited the lowest liver sequestration factor, indicating a higher elimination potential. The EQS for biota, expressed in PFOA-equivalents, ranged from 9.36 ng g⁻1 ww to 28.5 ng g⁻1 ww (mean: 18.5 ng g⁻1 ww), showing an overall increasing trend over the study period. The EWI for Baltic cod muscle (ΣPFAS-4) indicated an average exposure of 1.84 ng kg⁻1 body weight (bw) per week for adults, with a maximum of 3.46 ng kg⁻1 bw per week. For cod liver consumers, the maximum exposure reached 6.45 ng kg⁻1 bw per week, exceeding the Tolerable Weekly Intake (TWI) in some cases. The rising PFC concentrations in Baltic cod, especially in liver tissues, pose health risks to consumers. Ongoing monitoring and risk assessments are essential to reduce the impacts of PFC exposure from seafood.

Towards an environmental quality standard (EQS) for lithium in fresh water

Lithium (Li), because of its widespread and increasing use in Li-ion batteries, is an element of vital importance to the energy transition away from fossil fuels and toward clean, renewable energy (green energy). Extraction and refining operations, as well as utilisation in a growing number of applications, are expanding and thus increasing the environmental releases of Li. In order to evaluate consequences of such releases, and to risk assess the accumulation of Li in aquatic ecosystems, environmental quality standards (EQS) are needed so that measured concentrations can be evaluated. Satisfactory EQS for Li are yet to be established and therefore derivation of Predicted No Effect Concentrations (PNECs), or interim EQS, are vital for environmental protection. This study compiled Li freshwater ecotoxicology data from global literature, screened and evaluated it, and then employed it to derive PNECs for short term exposures (i.e. concentrations unlikely to cause harm if their duration is short) and PNECs for standard condition exposures (i.e. concentrations unlikely to cause harm if their duration is continuous) in freshwater ecosystems. The generated dataset comprised 194 individual ecotox endpoints from 31 reference sources, spanning 28 species from 10 separate taxonomic groups (broad organism types). The derived PNECs recommended for consideration in environmental regulation are 0.622 mg/L for short term exposures and 15.2 μg/L for standard condition exposures, but with potential adjustment for site specific water conditions incorporating water hardness, dissolved organic carbon concentration and pH.

Analysis of Biomass Co-firing Combustion Test using Corn Cobs at Punagaya CFPP as A Green Energy Alternative

Abstract Indonesia is determined to reduce fossil fuels by 2060 set a national renewable energy mix target of 23% by 2025 and be free of fossil fuels by 2060. One of the PLN’s (a national electrical company in Indonesia) efforts to increase carbon emissions reduction and strengthen local new renewable energy is co-firing biomass on CFPP. Indonesia, which is located in a tropical area, has a large potential for biomass resources. Corn cob, one of the biomass types, has a big potential to replace coal as fuel in CFPP especially in Jeneponto Region, South Sulawesi. By utilizing corn cobs as a fuel with a co-firing mechanism, it can generate green energy. The methodology for assessing the corn cob co-firing combustion test’s performance at Punagaya CFPP is presented in this paper. It is based on a multi-criteria assessment designed to examine the technical, financial, and environmental effects of operating parameters with a mixture composition of 95% coal and 5% corn cobs at 70 MW load for 10 hours. From the test results in terms of operational aspects, the parameters have changed but it still in the normal operating range; FEGT increased by 5.3°C, bed temperature increased by 8.9°C, air chamber pressure decreased by 0.05 kPa, and total airflow decreased by 4.5 T/h. From the financial aspect, it has benefited from a decrease in the value of Specific Fuel Consumption (SFC), which is 0.014 kg/kWh compared to 100% coal. From the environmental aspect, the overall results of emission parameters are still by environmental quality standards and have decreased for NOx and SO2 parameters.

Determination of soil environmental criteria for high-risk trace metals in urban park soils using improved CLEA model

The trace metals (TMs) accumulated in urban park soils can pose potential threats to human health, making the management of soil quality based on health risks critically important. Based on the human health risk assessment (HHRA) model coupled with Monte Carlo Simulation, this study improved the contaminated land exposure assessment (CLEA) model. Combined with local parameters, the Soil Environmental Criteria (SEC) for high-risk trace metals (TMs) in urban park soils were calculated. Results indicated that all the mean TCR (Total carcinogenic risk) values of seven TMs exceeded the risk threshold of 1E-06, suggesting a higher likelihood of carcinogenic risks for all populations. As and Cr presented the highest potential carcinogenic risks, and were identified as high-risk TMs in the study area. The traditional CLEA model was enhanced by incorporating region-specific data, optimizing exposure parameter calculations, and addressing parameter sensitivity and uncertainty. Using the improved CLEA model, the SEC values for high-risk TMs were calculated, revealing that the SEC values gradually increased from ages 1 to 18, while significantly decreased for individuals over 80 years old. This study effectively addresses issues of parameter uncertainty and sensitivity in the CLEA model, offering new insights for the development of soil environmental quality standards.

Derivation of environmental quality standards for free cyanide incorporating censored data into species sensitivity distributions

Free cyanide is considered to be the most toxic form of cyanides to aquatic life. Due to its broad range of uses and subsequent potential widespread emissions to surface water, the environmental effects of free cyanide have been extensively researched. Regulatory bodies have proposed water quality standards for free cyanide, but these are regularly debated and implementation has been inconsistent due to monitoring challenges. The aim of the present study was therefore to derive new environmental quality standards (EQS) for free cyanide according to the Water Framework Directive (WFD). Ecotoxicity data from previous derivations and an additional literature search were gathered and individually (re) evaluated on reliability. The pooled acute ecotoxicity dataset consisted of reliable results for 35 species, distributed over 8 taxonomic groups. The pooled chronic ecotoxicity dataset consisted of results for 13 species, distributed over 7 taxonomic groups. WFD criteria for deriving a species sensitivity distribution (SSD) were met, if censored data points were included. Using the R-package ETX 3.0, an SSD including censored data was constructed and acute and chronic HC5 values of 17 and 0.66 μg/L, respectively, were derived. Comparisons were made with alternative SSDs constructed by transforming or discarding the censored data. Applying a default assessment factor (AF) of 10 to the HC5 from the acute SSD resulted in a MAC-EQS of 1.7 μg CN/L for freshwater and marine water. Careful consideration was given to addressing the uncertainty around the chronic HC5 value for the selection of an AF of 3, resulting in an AA-EQS of 0.22 μg CN−/L for freshwater and 0.044 μg CN−/L for marine water by applying an additional AF of 5. It is concluded that the current environmental quality standards for free cyanide are the first to be derived according to the WFD guidance, using only reliable data and including censored values.

The ability of UWWTP to remove NSAIDs: Impact on water quality in the Odra River Czech Republic concerning incoming European legislation

Increased consumption of pharmaceuticals has resulted in their detection in wastewater. If wastewater treatment plants (WWTPs) fail to eliminate these substances adequately, they can seep into the environment, posing potential risks. As non-steroidal anti-inflammatory drugs (NSAIDs) belong to the pharmaceuticals most frequently examined in wastewater, this study aimed to monitor wastewater from the municipal wastewater treatment plant in Ostrava (UWWTP) over the course of a year, specifically assessing how the presence of these substances in discharged wastewater could contaminate the Odra River. To further understand the impact of NSAIDs, we evaluated the effectiveness of UWWTP technology in removing the following selected drugs: diclofenac (DCF), ibuprofen (IBU), naproxen (NAP) and ketoprofen (KET) - as well as their main metabolites: 4′-hydroxydiclofenac (hydroxyDCF), carboxyibuprofen (carboxyIBU), desmethylnaproxen (desmethylNAP), and ketoprofen glucuronide (glucuronideKET).Wastewater samples were collected at both the inflow and outflow of the urban wastewater treatment plant (UWWTP) Ostrava from October 2022 to September 2023. The analysis was performed using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The concentrations of the monitored substances at the UWWTP inflow varied significantly, ranging from 79 ng/L to 112,125 ng/L, with the highest levels detected for ibuprofen (IBU), diclofenac (DCF), and their metabolites. The UWWTP demonstrated impressive treatment efficiency for IBU, exceeding 98%, while for DCF, it ranged between 56% and 87%. Building on these findings, a monitoring campaign was initiated along the Odra River to evaluate the concentrations of IBU and DCF - substances that had not been measured before. Water samples were taken from various locations along the Odra River from October to November 2023 and analyzed using the same methodology as the wastewater samples. The results indicate that, in line with the proposed environmental quality standards (EQS), IBU and DCF do not pose a significant contamination risk to the Odra River.

Green and sensitive method combining ultrasonic solvent extraction, stir bar sorptive extraction and thermal desorption-gas chromatography–tandem mass spectrometry for determination of organotin compounds in sediment

A method integrating ultrasonic solvent extraction (USE) and stir bar sorptive extraction (SBSE) with thermal desorption-gas chromatography–tandem mass spectrometry (TD-GC–MS/MS) was developed and validated for determining critical organotin compounds (OTCs)—tributyltin (TBT) and triphenyltin (TPhT)—in sediment. In preparing a 0.5 g sediment sample, two 1-min cycles of US bath solvent extraction (using equal parts CH3COOH and MeOH), were followed by derivatization with NaBEt4 in the presence of a methanolic-aqueous solution of CH3COONa and SBSE for 1 h, achieving analyte recoveries of 64–94 %. Matrix-matched internal standard calibration and the use of an isotopically labelled recovery standard corrected for analyte losses and matrix effect (ME), ensuring accurate results for triorganotins. However, the method was not suitable for mono- and diorganotins due to low and anomalous recoveries caused by ME. Miniaturizing and optimizing the sample preparation reduced chemicals use and waste, contributing to the method being deemed ’an excellent green analysis’ by the Analytical Eco-Scale assessment. The method achieved a limit of quantification (LOQ) of 0.081 ng g−1 and an expanded uncertainty (U) value of 15 % for TBT, meeting the environmental quality standards (EQS) criteria of the European Union Water Framework Directive. Its applicability was demonstrated through the analysis of actual sediment samples and natural matrix certified reference materials.

Environmental risk of diclofenac in European groundwaters and implications for environmental quality standards

Groundwater harbours unique species adapted to perpetual darkness. Groundwater fauna plays a crucial role in global ecosystem services, but contamination poses a threat to this keystone ecosystem. Diclofenac is a common non-steroidal anti-inflammatory drug of particular concern, due to its presence in both surface and groundwater. We assess the environmental risk of diclofenac in European groundwaters using different scenarios, analyzing Measured Environmental Concentrations (MECs) of diclofenac and estimating the Predicted No Effect Concentration (PNECs) through two approaches: considering the sensitivity of the groundwater crustacean Proasellus lusitanicus (Isopoda: Asellidae), and using surface water species as proxies. Our results show that scenarios based on surrogate species predict that groundwater ecosystems are at risk due to diclofenac contamination. On the other hand, the MECs of diclofenac were consistently lower than the PNEC of P. lusitanicus, suggesting that the current MECs do not pose a significant threat to this groundwater-adapted species. However, risk scenarios differ considering the sensitivity of other groundwater species, emphasizing the importance of considering multiple species’ sensitivities in risk assessment. Therefore, we recommend establishing an environmental quality standard for diclofenac in groundwater at 5 ng/L, a value that accounts the need for precautionary measures to safeguard groundwater ecosystems, essential for preserving their unique biota and services.

Tracing nitrogen sources and transformation characteristics in a large basin with spatially heterogeneous pollution distribution

This study used dual stable isotopes to examine nitrate sources and geographical distribution in the Liao River Basin (LRB), one of China's seven major river basins. During a normal hydrological season in April 2021, water samples were taken from the main streams of the Liao River (MLR), Shuangtaizi River (STR), Hun River (HR), Taizi River (TZR), and Daliao River (DLR). Monitoring results indicated that 93% of the water samples had a total nitrogen level exceeding the Class IV limit (1.5 mg/L) of the ‘Environmental Quality Standards (EQS) for surface water’, indicating a serious nitrogen pollution status. 71.3% of the total nitrogen on average was in the form of nitrate. The scatterplots of δD-H2O and δ18O-H2O showed that water in TZR and DLR were mainly affected by precipitation, while MLR, STR and HR were additionally impacted by evaporation and groundwater. The overall δ15N and δ18O of NO3− varied from 7.7‰ to 17.9‰ and 0.6‰–11.2‰, respectively. The correlations between δ15N-NO3- and δ18O-NO3-, along with attribution results from the Bayesian isotopic mixing model, indicated a predominant role of manure/sewage (MS) pollution in affecting river nitrate, accounting for 78% of total nitrate in MLR and 72% in DLR. A positive correlation between δ15N-NO3- and δ18O-NO3- in MLR indicated the occurrence of denitrification process. Overall, attribution results showed that the primary nitrate sources varied in different river systems within such a large basin, mainly due to spatially varied land use and human activities. Tailored nitrogen management strategies should be implemented to address the main anthropogenic pressures.

Practical estimation and use of natural background concentrations in surface waters for nickel in Europe.

Estimates of ambient background concentrations in surface waters, referred to as natural background concentrations (NBCs) in European guidance documents, may be an important factor in determining whether a monitoring site meets the legally binding Environmental Quality Standard (EQS) when assessing naturally occurring substances. Here, we focus on utilizing routine regulatory surface water monitoring data to provide risk assessors and environmental practitioners with a transparent, implementable, repeatable, and resource-effective approach to estimate NBCs. The methodology does not use additional environmental sampling beyond that which is routine or require advanced statistical methods, or the incorporation of highly specialist, and not always readily accessible, local knowledge. It determines both whether a site is suitable for NBC assessment as well as the identification of suitable surrogate sites and local NBCs using 11 criteria: six for identifying if a site is suitable for NBC correction, and five for identifying suitable surrogate sites for local NBC values. The criteria consider both the extent of any EQS exceedance, after accounting for bioavailability in line with the European guidance and potential anthropogenic impacts at the site, and can be applied in a simple sequential procedure. The method has been applied to derive NBCs for nickel on three case-study countries-Cyprus, France, and Spain-to determine its useability and impact on compliance. The methodology presented addresses a gap in the current guidance regarding the practical and consistent implementation of NBCs and could be applied to other naturally occurring substances in an EQS or Water Quality Guideline compliance assessment process. Integr Environ Assess Manag 2024;00:1-14. © 2024 WCA Environment Ltd and NiPERA Inc. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Resistance to cephalosporins and quinolones in Escherichia coli isolated from irrigation water from the Rímac river in east Lima, Peru.

To evaluate the presence and sensitivity to antimicrobials of Escherichia coli strains isolated from 24 irrigation water samples from the Rimac river of East Lima, Peru. The E. coli strains were identified by PCR. Antibiotic susceptibility was processed by the disk diffusion method. Genes involved in extended spectrum beta-lactamases (BLEE), quinolones and virulence were determined by PCR. All samples exceeded the acceptable limits established in the Environmental Quality Standards for vegetable irrigation. Of the 94 isolates, 72.3% showed resistance to at least one antibiotic, 24.5% were multidrug resistant (MDR) and 2.1% were extremely resistant. The highest percentages of resistance were observed for ampicillin-sulbactam (57.1%), nalidixic acid (50%), trimethoprim-sulfamethoxazole (35.5%) and ciprofloxacin (20.4%). Among the isolates, 3.2% had a BLEE phenotype related to the bla CTX-M-15 gene. qnrB (20.4%) was the most frequent transferable mechanism of resistance to quinolones, and 2.04% had qnrS. It was estimated that 5.3% were diarrheagenic E. coli and of these, 60% were enterotoxigenic E. coli, 20% were enteropathogenic E. coli and 20% were enteroaggregative E. coli. The results show the existence of diarrheogenic pathotypes in the water used for irrigation of fresh produce and highlight the presence of BLEE- and MDR-producing E. coli, demonstrating the role played by irrigation water in the dissemination of resistance genes in Peru.

Enhancement of per- and Polyfluoroalkyl Substances (PFAS) quantification on surface waters from marinas in the douro river, Portugal

PFAS, known as "forever" compounds, are prevalent in various environments, including soils and aquatic systems, due to extensive usage. Surface waters in several European countries, especially marinas and ports with high boat traffic, require further study as potential contamination sources. Reliable methods for the extraction and quantification of these emergent compounds are essential. This study aimed to improve an existent solid phase extraction method to analyse marinas and ports’ surface waters with variable salinities (2, 9 and 17 PSU). The objectives were to: 1) optimise the solid phase extraction method, considering matrix salinity effects and cross-contaminations, 2) validate the extraction and quantification method of 18 EPA 537.1 PFAS in estuarine surface waters, using the Ultra-High Performance Liquid Chromatography – Quadrupole Time – Of – Flight – Tandem Mass spectrometry, and 3) apply the optimised method for PFAS quantification in three Portuguese marinas. All ICH criteria were successfully validated considering 9 PSU. Limits of quantification ranged from 117.80 ng/L to 385 ng/L, except for PFHpA (645.85 ng/L). PFAS levels (PFOA, HFPO-DA, PFBS, PFHxS and PFOS) were relatively low, reaching a maximum of 0.32 ng/L only for the PFOA. In Freixo marina, total average concentrations were slightly higher (∑PFAS = 1.02 ng/L) when compared to the ones found in Cais da Ribeira Port (∑PFAS = 0.94 ng/L) and Afurada marina (∑PFAS = 0.81 ng/L). PFOS concentrations are below the limit values set by the Environmental Quality Standards (36000 ng/L of PFOS for inland surface water, respectively), similar to other Portuguese river studies. This study enabled the development of a precise and reliable extraction and quantification method to quantify PFAS in estuarine surface waters, particularly from marinas. This method can be readily applied to analyse PFAS in other estuarine samples.

The Urgency of Setting Environmental Quality Standards by the Governor in the Context of Environmental Protection and Management in the Region

The environment is a crucial instrument in human life because it is where human life takes place. The environment is where humans develop and reproduce. Additionally, the environment is also a vital instrument in sustainable development within a country's region. The increasing critical land issues due to surpassing environmental quality standards indicate efforts towards environmental destruction, particularly in terms of wastewater standards. Humans fundamentally need natural resources such as land, water, and air. Therefore, if these components of natural resources are polluted or damaged, they can affect human life sustainability. Regarding wastewater quality standards, the Governor, as the government, is obliged to take action by establishing wastewater quality standards according to laws and regulations. However, if environmental quality standard parameters cannot adjust to the conditions of that region's environment, the Governor is obligated to tighten the determination of environmental quality standard parameters.

Cumulative characteristics and ecological risk source analysis of soil potentially toxic elements in the northern margin of the Tibetan Plateau.

To understand the soil toxic and hazardous elements content, pollution level, and ecological risk status in the northern margin of the Tibetan Plateau, we collected and analyzed 8273 sets of surface soil samples. Evaluations were conducted using the single-factor pollution index, geo-accumulation, pollution load, and potential ecological risk indices, and source identification correlation and principal component analysis. The results revealed that, compared with the background levels in China, the accumulation of soil arsenic, cadmium, nickel, and chromium was greater in the surface soil of the study area. Additionally, in comparison with Qinghai Province, more mercury accumulated in the surface soil of the study area and owing to the influence of anthropogenic activities. Benchmarking against soil environmental quality standards, the study area exhibited pollution control zones primarily dominated by arsenic and cadmium (3.9%). The spatial distribution revealed distinct zones: a ridge mountain type characterized by arsenic-cadmium-chromium-nickel, a Daban mountain type with solely cadmium presence, and a Longyangxia-Jianzha South type dominated by arsenic. Compared with the Qinghai Province soil background values, evaluations using the Pollution loading index, Geological Cumulative Index, and Potential Ecological Risk Index methods revealed varying degrees of potentially toxic element content exceedance. From an ecological risk perspective, the individual element with the highest potential ecological risk coefficients were mercury, followed by cadmium and arsenic; however, the region's overall ecological risk index was classified as low. Three distinct sources were identified: natural sources leading to high background levels of chromium, nickel, copper, zinc, and mercury; mixed natural and industrial/agricultural sources contributing to elevated cadmium levels; and human activity-related mercury enrichment. Based on the evaluation results, synergistic monitoring of soil and biota in naturally occurring risk zones is recommended to ensure the safety of agricultural and pastoral products. Additionally, ecological impact assessments and pollution source mitigation studies should be conducted in regions influenced by human activities to curb the further degradation of soil ecological quality.

Development of LC–MS/MS Method for the Simultaneous Detection of Emerging Contaminants in Aquatic Matrices

Emerging contaminants (ECs) are substances that have no defined environmental quality standards or regulations, and have the potential to pose major adverse impacts on the environment and human health. The detection of contaminants in the natural environment is the key step for establishing precise environmental risk assessment approach for ECs. However, ECs come from different origins with various physicochemical properties, making their detection a complicated process. Moreover, their presence in the aquatic environment at trace concentration range (ng/L-µg/L), requires an accurate detection at low concentration levels. This study aims to develop an efficient analytical method for simultaneous determination of 5 different ECs in aqueous solution based on solid phase extraction technique (SPE) followed by liquid chromatography-mass spectrometry (LC–MS/MS). High recovery rates (72% to 114%) were achieved for all targeted compounds. Ciprofloxacin (CIP), diuron (DIU), terbutryn (TER) and diclofenac (DIC) had a limit of detection (LOD) of 5 µg/L and a limit of quantification (LOQ) of 10 ng/L, while LOD and LOQ for EE2 were 25 µg/L and 50 ng/L, respectively. These results confirm that the optimized method can be applied for extraction and analysis of ECs from different classes in the aquatic environment.