Residues In Surface Water Research Articles

Agricultural Pesticide-Induced Physiological Stresses in Freshwater Fishes of Bangladesh

In Bangladesh, most croplands are situated in floodplains, enriched by numerous rivers and extensive freshwater wetlands. These areas also support productive open-water fisheries, crucial for supplying protein, generating income, creating jobs, and boosting the GDP. However, the widespread use of pesticides in these floodplains to protect crops and enhance food production leads to significant environmental issues. Agricultural pesticide residues enter water bodies through runoff, rainwater, drainage, seepage, and spray drift, contaminating natural water bodies and exerting continuous stress on aquatic life, including fish. Previous studies have detected pesticide residues in surface waters, sediments, and fish in Bangladesh, posing a major threat to wetland ecosystems. Research on freshwater fish species in Bangladesh has highlighted toxic effects on fish gonads, such as adhesion, inter-follicular space degeneration, ovigerous lamellae degeneration, necrosis, degenerated perinucleolar oocytes, cytoplasmic retraction in ovaries, and damage to sertoli cells. Additional observed effects include irregularly shaped seminiferous tubules, breakage of seminiferous tubules, and empty lumens in testes. Pesticides also inflict harm on other internal organs of fish, with gill effects like clubbing, reduction of gill filaments, telangiectasia of gill lamellae, hemorrhage, and damage to gill rakers. Kidney and liver damage include necrosis, cellular tissue degradation, acute cellular swelling, and irregular renal corpuscles, along with autolysis, vacuolation, and fatty changes in the liver. Developing embryos and larvae of freshwater fish are particularly vulnerable to the toxic effects of agro-pesticides. Studies reveal acute toxicity during early life stages, evidenced by deformities like edema, notochord deformity, caudal fin damage, yolk sac damage, posterior region damage, tissue fragmentation, black pigmentation on the yolk, body curvature, and lordosis in larvae. Exposed embryos exhibit deformities such as dark brown yolk sacs, notochord deformities, and broken eggshells. Mortality rates of fish embryos and larvae escalate with higher pesticide concentrations in water. Haemato-biochemical parameters serve as crucial indicators of pesticide exposure in fish studies, showing alterations in blood hemoglobin, glucose, RBC, WBC counts, and various erythrocytic abnormalities like twin cells, fusion, echinocyte formation, spindle-shaped, tear-drop, and elongated cells. Nuclear abnormalities include binucleated cells, nuclear buds, nuclear bridges, karyopyknosis, and notched nuclei. Research suggests that even at low concentrations, agro-pesticides disrupt physiological functions and life history traits of fish, adversely impacting the natural productivity and biodiversity of freshwater fish in Bangladesh.

A Wireless Network for Monitoring Pesticides in Groundwater: An Inclusive Approach for a Vulnerable Kenyan Population.

Safe drinking water is essential to a healthy lifestyle and has been recognised as a human right by numerous countries. However, the realisation of this right remains largely aspirational, particularly in impoverished nations that lack adequate resources for water quality testing. Kenya, a Sub-Saharan country, bears the brunt of this challenge. Pesticide imports in Kenya increased by 144% from 2015 to 2018, with sales data indicating that 76% of these pesticides are classified as highly hazardous. This trend continues to rise. Over 70% of Kenya's population resides in rural areas, with 75% of the rural population engaged in agriculture and using pesticides. Agriculture is the country's main economic activity, contributing over 30% of its gross domestic product (GDP). The situation is further exacerbated by the lack of monitoring for pesticide residues in surface water and groundwater, coupled with the absence of piped water infrastructure in rural areas. Consequently, contamination levels are high, as agricultural runoff is a major contaminant of surface water and groundwater. The increased use of pesticides to enhance agricultural productivity exacerbates environmental degradation and harms water ecosystems, adversely affecting public health. This study proposes the development of a wireless sensor system that utilizes radio-frequency identification (RFID), Long-range (LoRa) protocol and a global system for mobile communications (GSM) for monitoring pesticide prevalence in groundwater sources. From the system design, individuals with limited literacy skills, advanced age, or non-expert users can utilize it with ease. The reliability of the LoRa protocol in transmitting data packets is thoroughly investigated to ensure effective communication. The system features a user-friendly interface for straightforward data input and facilitates broader access to information by employing various remote wireless sensing methods.

Occurrence and ecological risks assessment of representative herbicides in a plateau alkali lake: Implications water management in prairie lakes

Herbicide residues in surface waters pose a potential hazard to aquatic ecosystems. Moreover, there is a scarcity of data regarding the occurrence of herbicide residues in lakes predominantly surrounded by non-agricultural land. This study aimed to monitor and assess seasonal variations in four commonly used herbicides (i.e., acetochlor, pretilachlor, butachlor, and atrazine) in the surface waters of the Hulun Lake Basin in China. The results indicated that the target herbicides were widely distributed throughout the study area.The residues of the four herbicides in surface water ranged from non-detectable levels to 1,978.60 ng L−1. Among the herbicides, atrazine had the highest detection rate (90.48 %). When considering the temporal factor, the median concentration of the selected herbicides in the lake was significantly higher during summer (102.68 ng L−1) than that during spring (97.59 ng L−1) and autumn (6.78 ng L−1). Furthermore, there were spatial variations in the surface waters of the Hulun Lake Basin. The residual levels in the lake exceeded those found in the inlet river, and the concentrations of herbicides in the estuary of the Kerulen River and central area of Hulun Lake were higher. The environmental risk assessment results indicated that the selected herbicides posed acceptable risks to fish in the aquatic environment of Hulun Lake. However, the risk quotient (RQ) values for acetochlor and atrazine in relation to algae exceeded 0.10. Similarly, the RQ values for butachlor in relation to algae and crustaceans exceeded 0.10 during the summer and autumn seasons and even surpassed 1.00 in certain samples. This can potentially endanger the survival of aquatic organisms. The findings of this study offer valuable insights to support efforts in pollution control, environmental safety assessments, and decision-making regarding water resource management in the Hulun Lake Basin.

Development and Validation of UFLC-MS/MS Analytical Method for the Simultaneous Quantification of Antibiotic Residues in Surface Water, Groundwater, and Pharmaceutical Waste Water Samples from South India.

Antibiotic residues in pharmaceutical wastewater pose a significant environmental concern due to their potential role in fostering antimicrobial resistance. South Indian pharmaceutical companies produce a wide range of antibiotics. As a result, the industries that discharge water may include antibiotic residues, which could be harmful to the environment. In this study, a novel, quick, accurate, and sensitive approach for the simultaneous detection of 11 antibiotics was established, and triple quadrupole mass spectrometry, ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS), and selective solid-phase extraction (SPE) were used for validation. Utilizing a mixed mode reversed-phase/cation-exchange cartridge (SPE using Strata X, 33 μm), the single-cartridge extraction procedure was performed and validated. Relative standard deviations for most of the antibiotics ranged from 3.5 to 0.56 with recoveries ranging from 57 to 85%. The samples were injected into the UFLC-MS/MS apparatus at a volume of 10 μL for analysis. The auto sampler cooler temperature was kept at 150 °C, while the column temperature was kept at 40 °C. After validation, the technique was determined to be linear in the range of 2.0-1000.0 ng/mL. The retention period for antibiotics was between 1.2 and 1.5 min. Antibiotics transitions for multiple reaction monitoring| were between 235.1/105.9 and 711.5/467.9 m/z. The method of analysis took 2.5 min to run completely. Antibiotic residues were efficiently analyzed using the established analytical approach in pharmaceutical wastewater (influent and effluent), surface, and groundwater. Eleven antibiotics were found in the water samples during examination with concentrations ranging between 2.313 and 95.744 ng/L. The procedure was shown to be much more environmentally friendly than other contemporary methods based on the green analytical procedure index's evaluation of greenness. Blue applicability grade index tool indicated the developed method's practicality in comparison with that of other reported method.

Pesticide screening of surface water and soil along the Mekong River in Cambodia

Widespread use of pesticides globally has led to serious concerns about environmental contamination, particularly with regard to aquatic and soil ecosystems. This work involved investigating concentrations of 64 pesticides in surface-water and soil samples collected in four provinces along the Mekong River in Cambodia during the dry and rainy seasons (276 samples in total), and conducting semi-structured interviews with local farmers about pesticide use. Furthermore, an ecological risk assessment of the detected pesticides was performed. In total, 56 pesticides were detected in surface water and 43 in soil, with individual pesticides reaching maximum concentrations of 1300 ng/L in the surface-water samples (tebufenozide) and 1100 ng/g dry weight in the soil samples (bromophos-ethyl). The semi-structured interviews made it quite evident that the instructions that farmers are provided regarding the use of pesticides are rudimentary, and that overuse is common. The perceived effect of pesticides was seen as an end-point, and there was a limited process of optimally matching pesticides to pests and crops. Several pesticides were used regularly on the same crop, and the period between application and harvest varied. Risk analysis showed that bromophos-ethyl, dichlorvos, and iprobenfos presented a very high risk to aquatic organisms in both the dry and rainy seasons, with risk quotient values of 850 for both seasons, and of 67 in the dry season and 78 in the rainy season for bromophos-ethyl, and 49 in the dry season and 16 in the rainy season for dichlorvos. Overall, this work highlights the occurrence of pesticide residues in surface water and soil along the Mekong River in Cambodia, and emphasizes the urgent need for monitoring and improving pesticide practices and regulations in the region.

Detection of Beta-Lactam residues in environmental and drinking water by immunoenzymatic assay

In recent decades, concern over emerging organic contaminants in the environment has grown considerably because of their potentially harmful effects on organisms and ecosystems. These synthetic compounds are widely used in modern life-style and due to improvements in analytical technologies, we are now able to identify and quantify them even in small concentrations. One of the most important pharmaceutical contaminants is antibiotics, of which more than half belong to the class of beta-lactams. This research aimed to determine the beta-lactam antibiotics residues in surface water (rivers) and groundwater, which serve as public or private sources of drinking water, as well as in urban wastewater. The samples were collected from different places throughout the Western part of Romania and analyzed using commercially available ELISA kits for the detection of beta-lactams in liquid samples. The results show that betalactam antibiotics are ubiquitous in all categories of water and establish the ELISA method as an acceptable screening tool for antibiotic residues.

Identification of point and nonpoint emission sources of neonicotinoid pollution in regional surface water

Neonicotinoid insecticides are widely applied in farmland, with high detection rates in soils and surface waters, posing potential risks to biodiversity and human health. As a nonpoint emission, surface runoff is widely regarded as the major source of neonicotinoid pollution in surface waters, but few studies have determined the point source contribution to rivers that may be primarily from wastewater treatment plants (WWTPs). Here, we collected the surface water from eight river basins in Zhejiang Province of China and quantified residual concentrations of eight widely commercialized neonicotinoids. Four of these were detected in all samples, with concentrations of dinotefuran and nitenpyram of 119 ± 166 and 87.6 ± 25.3 ng/L, respectively, representing more than 90 % of the total (282 ± 174 ng/L). Neonicotinoid residues were higher in tributaries due to nearby farmland and more dilution effects in the mainstream, and the residues were higher in lower reaches which can be explained by the water flow direction. Significant spatial differences in neonicotinoid distribution between surface water and agricultural soils result from environmental factors (e.g., water turbidity, precipitation, temperature) impacting migration and transport processes. Neonicotinoid residues in surface water showed a significant positive correlation with total WWTP emissions after adjusting for environmental factors. Conversely, no significant association was observed with cropland density (a nonpoint emission source), indicating that point emission source (contributing 20.6 %) predominantly influenced neonicotinoid residue spatial variation in river basin-scale surface water.

The photolytic breakdown of caffeine and paracetamol residues in surface water.

High concentrations of the most consumed pharmaceuticals, caffeine and paracetamol, have been observed globally in wastewater treatment plant discharge. Here, we assess the potential for photodegradation of caffeine and paracetamol residues at concentrations like those observed in treated wastewater discharges to the environment. Laboratory assays were used to measure rates of photodegradation of these two compounds both in distilled water and in natural river water with leaf litter leachate. When exposed to artificial light simulating natural sunlight, the half-life values of caffeine and paracetamol were significantly shorter than in the dark. The presence of organic matter increased caffeine and paracetamol half-life by lessening the photolytic effect. These results suggest that photolysis is a substantial contributor to the degradation of caffeine and paracetamol. The findings contribute to our understanding of persistence of pharmaceuticals in treated wastewater discharge. PRACTITIONER POINTS: The photodegradation of caffeine and paracetamol residues in surface water was examined. With leaf litter leachate, caffeine and paracetamol were photodegraded in distilled and natural river water in laboratory. Caffeine's half-life ranged from 2.3 to 16.2 days under artificial sunlight andparacetamols from 4.3 to 12.2 days. When incubated in the dark, the half-life for both compounds exceeded 4 weeks. Organic matter decreased the photolytic action of caffeine and paracetamol.

Development and validation of a GC × GC-ToFMS method for the quantification of pesticides in environmental waters

Water is a fundamental resource for living things, which is why its control is necessary. The widespread use of pesticides for agricultural and non-agricultural purposes has resulted in the presence of their residues in surface water and groundwater resources. Their presence in water is regulated through different directives, such as the Groundwater Directive, the Drinking Water Directive, and the Water Framework Directive, modified later several times, setting a maximum concentration of 0.1 µg.L−1 for individual pesticides and their degradation products, and 0.5 µg.L−1 for total pesticide residues present in a sample. There are different kinds of pesticides (e.g., organophosphorus and organochlorine pesticides, triazines, chloroacetamides, triazoles, (thio)carbamates) that have diverse chemical structures. Their determination and monitoring in a single analytical procedure are possible through multiresidue methods. In this study, 53 pesticides belonging to different chemical classes and their metabolites were selected based on their local occurrence and investigated in surface water and groundwater from agricultural areas susceptible to pesticide contamination. The methodology consisted of a classical solid-phase extraction (SPE) for the purification and enrichment of the pesticides, with a subsequent analysis in multidimensional gas chromatography coupled to mass spectrometry (GC×GC-MS). The quantification method was validated according to the Eurachem Guide in terms of linearity, precision, accuracy, limit of detection, and limit of quantification. After validation, the method was applied to 34 real-world water samples, and the results were compared with those obtained by a GC-QMS routine method.

Profiling of Antibiotic Residues in Surface Water of River Yamuna Stretch Passing through Delhi, India

The River Yamuna is one of the largest rivers in northern India. It serves as a major source of potable water to the National Capital Delhi. A study was carried out to monitor and quantify three common antibiotics in surface water, with the help of Ultra-Performance Liquid Chromatography (UPLC) coupled with the Mass spectrophotometer (MS/MS)-based method. All the major river water locations in the research area were sampled in triplicate to determine the significant presence of antibiotics from local areas, hospitals, drug manufacturing facilities, and residential areas. Using spiked, as well as actual samples, an optimized method for the detection and quantification of different concentrations of antibiotics was developed. Spatiotemporal variations in the physicochemical properties at the five sites, including reference site-6 (Jamia Millia Islamia), during the pre-monsoon and post-monsoon period, were also investigated. Maximum concentration was observed during the pre-monsoon season followed by the post-monsoon season. The highest detected antibiotic concentration from the river water samples was that of ofloxacin (145.3794 ng/mL), followed by amoxicillin (3.033 ng/mL) and erythromycin (2.171 ng/mL). An aquatic environment may be very vulnerable to dangers from these pharmaceutical residues, according to this risk assessment. Additionally, the levels and compositions of pharmaceutical residue in the aquatic ecosystem might be influenced by seasonal agricultural application, precipitation, and temperature. The findings revealed the existence of antibiotics because of their indiscriminate usage, which may have resulted in the development of resistant strains and ultimately contributed to the spread of antibiotic resistance among living organisms in the river. Thus, attention is required particularly to this section of river as it is the local lifeline source for urban consumers for the domestic water supply and farmers for cultivation.

Pharmaceuticals and personal care products (PPCPs) in surface water and fish from three Asian countries: Species-specific bioaccumulation and potential ecological risks

In Asian developing countries, undeveloped and ineffective sewer systems are causing surface water pollution by a lot of contaminants, especially pharmaceuticals and personal care products (PPCPs). Therefore, the risks for freshwater fauna need to be assessed. The present study aimed at: i) elucidating the contamination status; ii) evaluating the bioaccumulation; and iii) assessing the potential risks of PPCP residues in surface water and freshwater fish from three Asian countries. We measured 43 PPCPs in the plasma of several fish species as well as ambient water samples collected from India (Chennai and Bengaluru), Indonesia (Jakarta and Tangerang), and Vietnam (Hanoi and Hoa Binh). In addition, the validity of the existing fish blood–water partitioning model based solely on the lipophilicity of chemicals is assessed for ionizable and readily metabolizable PPCPs. When comparing bioaccumulation factors calculated from the PPCP concentrations measured in the fish and water (BAFmeasured) with bioconcentration factors predicted from their pH-dependent octanol–water partition coefficient (BCFpredicted), close values (within an order of magnitude) were observed for 58–91 % of the detected compounds. Nevertheless, up to 110 times higher plasma BAFmeasured than the BCFpredicted were found for the antihistamine chlorpheniramine in tilapia but not in other fish species. The plasma BAFmeasured values of the compound were significantly different in the three fish species (tilapia > carp > catfish), possibly due to species-specific differences in toxicokinetics (e.g., plasma protein binding and hepatic metabolism). Results of potential risk evaluation based on the PPCP concentrations measured in the fish plasma suggested that chlorpheniramine, triclosan, haloperidol, triclocarban, diclofenac, and diphenhydramine can pose potential adverse effects on wild fish. Results of potential risk evaluation based on the PPCP concentrations measured in the surface water indicated high ecological risks of carbamazepine, sulfamethoxazole, erythromycin, and triclosan on Asian freshwater ecosystems.

Comparison of ribavirin degradation in the UV/H2O2 and UV/PDS systems: Reaction mechanism, operational parameter and toxicity evaluation

Residues in surface water of ribavirin, which used extensively during the COVID-19 pandemic, have become an emerging issue due to its adverse impact on the environment and human health. UV/H2O2 and UV/peroxydisulfate (PDS) have different degradation effects on ribavirin, and the same operational parameter have different effects on the two processes. In this study, the reaction mechanism and degradation efficiency for ribavirin were studied to compare the differences under UV/H2O2 and UV/PDS processes. We calculated the total rate constants of ribavirin with HO• and SO4•- in the liquid phase as 2.73 × 108 and 9.39 × 105 M−1s−1. The density functional theory (DFT) calculation results showed that HO• and SO4•- react more readily with ribavirin via H-abstraction (HAA). The nitrogen-containing heterocyclic ring is difficult to undergo ring-opening degradation. The UV/PDS process was more stable and performed better than the UV/H2O2 for the ribavirin degradation when the same molar oxidant dosage was applied. HO• plays an extremely important role in the degradation of ribavirin by UV/PDS. The reason for this phenomenon is the combination of the higher yield of HO• produced in the UV/PDS process and the faster reaction rate of ribavirin with HO•. The UV/H2O2 process is more sensitive to pH than UV/PDS. Alkaline condition can significantly inhibit the ribavirin degradation. The effects of natural organic matter (NOM) and ribavirin concentration were also compared. Eventually, the toxicity prediction of the product showed that the opening-ring products were more toxic than the parent compound.

Occurrence of organochlorine residues in surface water and mussel Corbicula sumatrana from Lake Singkarak, West Sumatera

Organochlorine is a synthetic pesticide that has been banned in many countries because of its high persistence in the environment and can accumulate in animals. The goal of our study was to determine the level of organochlorine residues in surface water and in the mussel Corbicula sumatrana of Lake Singkarak. Water and mussel samples were collected from 10 sampling sites of Lake Singkarak, Batu Taba, Sumpur, Guguk Malalo, Ombilin, Tikalak, Sumani, Saniang Baka, Muaro Pingai, Paninggahan, and Tanjung Mutuih, respectively in June 2021. Water and mussel samples were extracted and analyzed with gas chromatography. The result of our study revealed the occurrence of Lindan (7 μg/L) in the surface water of Tikalak, and also Aldrin (3 μg/L) in the surface water of Tikalak, Sumani, and Ombilin. Organochlorine residue compounds were also detected in mussels of five sampling sites (Tikalak, Sumani, Muaro Pingai, Paninggahan, and Tanjung Mutuih). Mussels of Tikalak contain compounds namely Dieldrin, Dichlorodiphenyltrichloroethane (DDT), and Endosulfan with levels of 2 μg/kg, 6 μg/kg, and 3 μg/kg, respectively. Dieldrin was also detected at Sumani (2 μg/kg), Muaro Pingai (4 μg/kg), and Paninggahan (10 μg/kg). DDT was also detected at Tanjung Mutuih at a level of 3 μg/kg. Other compounds such as Heptachlor and Endrin were not detected both in surface water and in mussel from all sampling sites studied. The results indicate that organochlorine residue can still be found in the environment, with its level in mussels being higher than in surface water.

Accumulation of organochlorine pesticide (OCP) residues in surface water and sediment from the İznik Lake in Turkey.

This study was carried out to evaluate organochlorinated pesticide (OCPs) concentrations in the water column and sediments of İznik Lake. Water samples and sediment were collected in different regions (six sampling sites) of the lake between January and December 2019 and tested for OCPs by gas chromatography-mass spectrometry (GC-MS). The results revealed that OCP residues throughout the sites varied depending on the anthropogenic activities of the region. OCPs detected in surface waters ranged from 0.01 to 60.80μg/L and sediments from 0.06 to 14.21ng/g dw. Endrin ketone, endrin aldehyde, endosulfan II, endrin, heptachlor epoxy, beta-BHC, gamma-BHC, ppDDD, and ppDDT concentrations exceeded the maximum residue limits indicated by the World Health Organization (WHO) for surface waters. Of the 18 analyzed OCP components, 17 were detected in sediment samples, and it was noted that they reached the highest concentration in summer. The presence of relatively high OCP levels according to WHO regulations in the waters of İznik Lake, around which agricultural activities have been increasing rapidly in recent years, is a serious concern, and therefore, appropriate actions should be taken into consideration by the regulatory authorities.

Modified Peanut Shell as an Eco-Friendly Biosorbent for Effective Extraction of Triazole Fungicide Residues in Surface Water and Honey Samples before Their Determination by High-Performance Liquid Chromatography.

An eco-friendly sample preparation method that is based on the use of a modified peanut shell as an efficient biosorbent for the extraction of triazole residues before their analysis by high-performance liquid chromatography was reported. The four triazole fungicides were separated on a Purospher STAR RP-18 endcapped (4.6 × 150 mm, 5 μm) column with a mobile phase of 50% (v/v) acetonitrile at a flow rate of 1.0 mL min–1 and detection wavelength set at 220 nm. Peanut shells modified by didodecyldimethylammonium bromide were selected as an effective biosorbent material in the microextraction method. Scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy were used to characterize the biosorbent. The effect of dominant parameters on the proposed microextraction method including the amount of sorbent, kind and concentration of surfactant, sodium hydroxide concentration, kind and amount of salt, sample volume, adsorption time, kind and volume desorption solvent, and desorption time was studied. Under the optimum condition, a good analytical performance for the proposed microextraction method was obtained with a wide linear range within the range of 9–1000 μg L–1, and low limits of detection (0.03 μg L–1 for all analytes) were obtained. Enrichment factors were achieved within the range of 30–51. The intra and interday precision values were evaluated in terms of percentage relative standard deviations (%RSD) and were less than 0.09 and 5.34% for the retention time and peak area, respectively. The proposed microextraction methods were used for extraction and analysis of triazole fungicides in water and honey samples. The recoveries in a satisfactory range of 70.0–118.8% were obtained.

Ecological Risk Assessment of Pharmaceutical Residues in Surface Water.

Pharmaceutical compounds have been frequently detected in the aquatic environment globally and are suspected to have some negative health consequences. The present study evaluates the sources, occurrences, spatiotemporal variabilities, concentrations, and potential risks of some pharmaceutical residues in surface water of Isolo and Amuwo Odofin areas of Lagos Nigeria. surface water samples were collected bi-monthly for a period of twenty-four months. The samples were filtered with 0.45µm glass fiber and analyzed using HPLC with a UV detector. Solid-phase extraction was achieved with OASIS HLB cartridges C18 for pre-concentration of 500ml of the sample. The target analytes were acetaminophen, ibuprofen, diclofenac, metronidazole, amoxicillin, sulfadoxin, pyrimethamin, ofloxacin, ciprofloxacin and caffeine. Levels of pharmaceutical residues (PRs) in the water samples ranged from 1.261-5.035ng / L for ibuprofen, 0.484 - 2.366ng / L for diclofenac, nd -3.57 ng / L for sulfadoxin, 0.976 -3.440 for ofloxacin, 0.585 - 0.706 ng / L for ciprofloxacin, 0.187-1.228ng / L for caffeine, 0.395-1.329 ng / L for acetaminophen and 0.032 – 0.598 ng / L for metronidazole. Amoxicillin and pyrimethamine were not detected in all the samples. The order of concentration of the pollutants are Ibuprofen > diclofenac > ofloxacin > sulfadoxin > acetaminophen> caffeine > caffeine > ciprofloxacin > metronidazole .Measured sample concentrations were compared with the approved values in “European Committee on antimicrobial susceptibility (EAUCAST)” database and some of the detected pharmaceutical compounds were found to be of high concentrations. Ecological risk assessments of each pharmaceutical active ingredient was evaluated and Rist Quotients (RQ) > 1 were found for metronidazole, ofloxacin and ciprofloxacin, indicating high risk. The need for improved wastewater treatment technologies cannot be over emphasized. Continuous monitoring and better regulatory frameworks may be necessary.

Atrazine Residues in Surface Water from Various Agricultural Areas of El-Behera Governorate, Egypt

Atrazine Residues in Surface Water from Various Agricultural Areas of El-Behera Governorate, Egypt

A Simple Dispersive Micro-Solid Phase Extraction for Determination of Neonicotinoid Insecticides in Surface Water and Fruit Juice Samples

A dispersive micro-solid phase extraction (D-μ-SPE) has been investigated for simple microextraction and preconcentration of fi ve neonicotinoid insecticides residues followed by highperformance liquid chromatography. The neonicotinoid insecticides including thiamethoxam, clothianidin, imidacloprid, acetamiprid, and thiacloprid, were separated on LiChroprep® 100 RP-8 endcapped column using 25% (v/v) acetonitrile with a fl ow rate of 1.0 mL min−1. LiChroprep® RP-18 (C-18) was chosen as an effi cient adsorbent in d-μ-SPE. The experimental parameters affecting the extraction performance of D-μ-SPE were investigated including salt addition, amount of sorbent, sample volume, and kind and volume of desorption solvent. Under the selected conditions, linearity was found in the range of 0.003-0.1 μg mL−1. Low limit of detection and high enrichment factor (11 – 81) were obtained. The proposed method was successfully applied for the determination of neonicotinoid insecticide residues in surface water and fruit juice samples with high obtained recoveries.

Distribution of Organochlorine Pesticide Residues in Surface Water and Sediments of Ogun River at Kara Abattoir, Ogun State, Nigeria

In this study, the levels of organochlorine pesticide (OCPs) in Ogun River, at Kara abattoir were investigated to estimate the extent of pesticide pollution in the river. Two sets of water and sediment samples (A and B) were collected. Samples A were collected in April (during heavy downpour) and samples B in June (under dry weather condition). Most of the physico-chemical parameters in the water and sediment samples were within WHO limits, except the samples taken during heavy downpour. In the water samples, the DDT and metabolites (2.023±0.586 µg/L), endrin (0.671±0.256 µg/L) and aldrin and dieldrin (8.290±2.891 µg/L) exceeded 1 µg/L, 0.6 µg/L and 0.03 µg/L respectively in the WHO (2006) guideline, whereas lindane (0.046±0.034 µg/L) and methoxychlor (0.757±0.281 µg/L) were below 2 µg/L and 20 µg/L respectively in the guideline. OCP residual levels in samples A were much higher than in B. This could be attributed to the massive draining and heavy disturbance of the river during the heavy downpour when samples A were collected.

Comprehensive assessment of chemical residues in surface and wastewater using passive sampling, chemical, biological, and fish behavioral assays

Effluents from ten full-scale municipal wastewater treatment plants (WWTPs) that discharge into the Hudson River, surface waters, and wild-caught fish samples were analyzed using liquid chromatography with tandem mass spectrometry (LC/MS/MS) to examine the influence of wastewater discharge on the concentrations of contaminants of emerging concern (CECs) and their ecological impacts on fish. Analysis was based on targeted detection of 41 pharmaceuticals, and non-targeted analysis (suspect screening) of CECs. Biological effects of treated WWTP effluents were assessed using a larval zebrafish (Danio rerio) swimming behavior assay. Concentrations of residues in surface waters were determined in grab samples and polar organic chemical integrative samplers (POCIS). In addition, vitellogenin peptides, used as biomarkers of endocrine disruption, were quantified using LC/MS/MS in the wild-caught fish plasma samples. Overall, 94 chemical residues were identified, including 63 pharmaceuticals, 10 industrial chemicals, and 21 pesticides. Eight targeted pharmaceuticals were detected in 100% of effluent samples with median detections of: bupropion (194 ng/L), carbamazepine (91 ng/L), ciprofloxacin (190 ng/L), citalopram (172 ng/L), desvenlafaxine (667 ng/L), iopamidol (3790 ng/L), primidone (86 ng/L), and venlafaxine (231 ng/L). Over 30 chemical residues were detected in wild-caught fish tissues. Notably, zebrafish larvae exposed to chemical extracts of effluents from 9 of 10 WWTPs, in at least one season, were significantly hyperactive. Vitellogenin expression in male or immature fish occurred 2.8 times more frequently in fish collected from the Hudson River as compared to a reference site receiving no direct effluent input. Due to the low concentrations of pharmaceuticals detected in effluents, it is likely that chemicals other than pharmaceuticals measured are responsible for the behavioral changes observed. The combined use of POCIS and non-target analysis demonstrated significant increase in the chemical coverage for CEC detection, providing a better insight on the impacts of WWTP effluents and agricultural practices on surface water quality.