Contamination Problems Research Articles

Development and application of a quadruple RT-qPCR assay for the simultaneous detection of NoV GI, NoV GII, and HAV in bivalve shellfish.

To achieve rapid and simultaneous detection of NoV GI, NoV GII, and HAV, a quadruple real-time fluorescence quantitative PCR (RT-qPCR) assay was developed using MS2 bacteriophage as a process control virus. The quadruple RT-qPCR assay effectively detected NoV GI, NoV GII, HAV, and MS2 RNA with detection limits of 102 copies/μL, 103 copies/μL, 102 copies/μL, and 103 copies/μL, respectively, within 1 hour 50 minutes. The quadruple RT-qPCR assay could specifically detect NoV GI, NoV GII, HAV, and MS2 without cross-reactions with other common pathogens, demonstrating good reproducibility with intra-assay and inter-assay coefficients of variation all below 2.11%. In this study, 337 bivalve shellfish samples collected from various regions of Hebei Province were pretreated using the proteinase K-PEG 8000 precipitation-chloroform method, and viral nucleic acids were enriched and extracted from a volume of viral solution that was doubled. The developed quadruple RT-qPCR assay was used to detect NoV GI, NoV GII, and HAV in bivalve shellfish samples, and the positive rates were 19.88% (67/337), 20.47% (69/337), and 4.75% (16/337), respectively. In addition, mixed infections of NoV GI and NoV GII (10.68%, 36/337) and NoV GI and HAV (0.89%, 3/337) were observed. In all, 200 bivalve shellfish samples were randomly selected for the assay, and it was found that the total, positive, negative coincidence rates, and Kappa values of the quadruple RT-qPCR assay were 98.3%, 99.1%, 98.2%, and 0.945, respectively, compared with the single RT-qPCR assay. These results show that the developed quadruple RT-qPCR assay has comparable performance to the single RT-qPCR assay.IMPORTANCEFood-borne diseases caused by viral contamination have become a growing concern, and bivalve shellfish is a crucial source of infection, with many outbreaks of non-bacterial acute gastroenteritis associated with raw food or the use of undercooked shellfish such as oysters. As food contamination problems caused by NoV and HAV become more severe, it is important to study and establish a sensitive and efficient assay to simultaneously detect NoV and HAV by applying the MS2 process control virus for the protection of bivalve shellfish food safety and the monitoring of the above food-borne viral contamination. In addition, bivalve shellfish samples contain a large number of PCR inhibitors such as polysaccharides, lipids, and proteins, so optimization of the virus enrichment and extraction method is essential and is expected to provide a research basis for subsequent related experiments.

Arsenic Contamination in Sludge and Sediment and Relationship with Microbial Resistance Genes: Interactions and Remediation

Arsenic contamination in sludge and sediment has emerged as a pressing environmental issue with far-reaching implications. This review delves into the multifaceted problem of arsenic contamination, focusing on its complex interactions with microbial resistance genes (MRGs). It explores the key role of microorganisms in the biogeochemical cycling of arsenic, including processes such as reduction, oxidation, methylation, and volatilization. It describes how microorganisms resist arsenic through resistance genes that encode proteins such as efflux pumps, enzymatic detoxification, and intracellular sequestration. Arsenic, a naturally occurring element, can enter sludge and sediment through various natural and anthropogenic pathways, leading to detrimental effects on environmental quality. Understanding the role of microorganisms in arsenic mobilization, transformation, and their ability to resist arsenic toxicity through MRGs is essential for effective mitigation and remediation strategies. This review discusses the sources and distribution of arsenic in sludge and sediment, the intricate mechanisms of microbial arsenic resistance, and the potential implications for environmental management and human health. It also examines current research trends and identifies areas requiring further investigation. By unraveling the interplay between arsenic contamination, microorganisms, and MRGs, this review aims to contribute to a deeper understanding of the issue and guide future research and environmental protection efforts.

Experimental Investigations for Assessment of Carbon Emissions and Tool Temperature in Dry Turning Operation Using Al1070 Alloy

Dry turning operations are required to be performed during production to achieve sustainable development goals as per environmental protection guidelines. In such machining operations, there is no need of supply of mineral based cutting fluids (MBCF) which creates problems of environment contamination and health risks to operators such as lung cancer, eye irritation and skin diseases etc. Al1070 alloys are currently used in construction industry, transport, communication cables and refrigerator cabinets as light weight structural material. The main objectives of the present study are to explore the dry turning operation (without use of MBCF) using Al1070 alloy. The X-ray fluorescence elemental analysis was performed to check composition of MBCF. Several harmful elements such as phosphorus, chlorine, and zinc dialkyl dithiophosphate were present which create high health risk to operators in turning operation with MBCF. The work piece, the cutting tool, the electricity consumption, and the recycling of the chips during the turning process contributed to the total carbon emissions. Significant positive impacts on environment have been achieved in dry turning operation as compared to tuning with MBCF. 19.85% reduction in carbon emissions and 37.12% reduction in tool temperature were achieved in dry turning operation with minimal tool wear and surface defects.

Your Clean Graphene is Still Not Clean

AbstractResearchers working with thin samples, such as monolayer graphene, are consistently struggling against contamination. Indeed, the problem of hydrocarbon contamination is known from the earliest days of electron microscopy and efforts to reduce this problem are ubiquitous to almost all high‐vacuum experiments. Accurate knowledge of the behavior of such contamination is essential for electron beam (e‐beam) based atomic fabrication, where it is aspired to select and control matter on an atom‐by‐atom basis. Here, the vexing question of hydrocarbon contamination on graphene is taken up. Image intensity is used to directly reveal the presence of diffusing hydrocarbons on ostensibly clean graphene. These diffusing hydrocarbons are previously inferred but not directly observed. Surprising dynamic variations of the concentration of these hydrocarbons impels questions about their origin. Here, some possible explanations are presented and some tentative conclusions are drawn. This work updates the conceptual model of “clean graphene” and offers refinements to the description of e‐beam induced hydrocarbon deposition.

Exploring of laccase-like nanozyme and membrane filters for efficient removal of tetracycline hydrochloride

Laccase is utilized as green catalyst in the environmental catalysis. Nevertheless, the drawbacks such as poor stability and difficulty in recycling have seriously restricted its application. Here, we simulated the binding pocket and catalytic active site of nature laccase, and designed a laccase-mimicking nanozyme (named as GA-Cu and the average diameter was 600 nm) with high activity and stability by using Cu2+ as the active center, 2-aminoimidazole as well as glutathione (GSH) as the ligand. Compared with natural laccase, the GA-Cu nanozymes showed excellent stability and reusability under extreme conditions. Furthermore, to overcome the problems of difficult recycling and easy secondary contamination, we innovatively proposed to load GA-Cu nanozymes onto nylon membranes (GA-Cu@CS/GA-Cu/nylon membranes) by vacuum-assisted filtration using chitosan (CS) as a binder to degrade tetracycline hydrochloride (TC) by filtration. Encouragingly, 50 mg/L of TC was almost completely removed by filtration once at 0.15 MPa pressure. The results have showed that the GA-Cu@CS/GA-Cu/nylon membrane removed TC mainly through degradation, and more than 80 % of TC was degraded through desorption experiments. Finally, some degradation products were identified by LC-MS and three possible degradation pathways were proposed. These findings demonstrate the potential of GA-Cu@CS/GA-Cu/nylon membrane for environmental remediation, and will be a general and important strategy for the design of membrane filters based on the excellent performance of nanozyme.

Https://agroecoinfo.ru/TEXT/RUSSIAN/nomer_2024_6.html

This article examines the problem of concomitant contamination of soils with heavy metals after long-standing oil spills in the Republic of Bashkortostan. The results of a study on changes in the gross content of heavy metals in different types of soils are presented. Studies have shown that among the studied gross forms of heavy metals (Zn, Cu, Pb, Ni) in areas with long-standing oil spills there is no correlation with the content of petroleum products. The content of all forms of the studied metals did not exceed the requirements of sanitary and hygienic standards and the geochemical background characteristic of the studied territory. Keywords: HEAVY METALS, GRAY FOREST SOIL, TYPICAL CHERNOZEM, ALLUVIAL MEADOW SOILS, OIL POLLUTION

Microplastics influence nutrient content and quality of salt-affected agricultural soil under plastic mulch

Northeast China is an important food production base and plays a crucial role in national food security. However, the increase in salt-affected soils poses a challenge to agricultural production in this region. Plastic mulching is an effective technique for saline cropland improvement, and although it has increased crop yields in the short term, its long-term application may have introduced the problem of contamination by microplastics (MPs). The distribution of MPs in salt-affected cropland, along with the effects on soil nutrients, remains largely unknown. Accordingly, the presented research selected salt-affected cropland as the research object, after which MPs were quantified from 46 soil samples from currently mulched and unmulched fields. MPs abundance in the sampled soils ranging from 4.10 × 103∼1.50 × 104 particles per kilogram of dry soil. The detected MP polymers were mainly high-density polyethylene (46%), polypropylene (22%) and polyvinyl chloride (20%). The MP particles most commonly fell under the size ranges of 50∼100 μm (35%) and 100–200 μm (28%), both of which are small particle sizes. The most commonly detected MP shapes were film (34%) and fragment (31%). The mulched samples from salt-affected cropland generally showed higher soil nutrient contents than the unmulched samples. Moreover, MP abundance, type, size, and shape all demonstrated strong correlations with soil organic carbon and total nitrogen. MP type is a major factor determining soil nutrient content. Plastic mulching serves as an important source of MPs in salt-affected cropland, with these contaminants affecting nutrient content. Future research should be broader in scope and include ecological benefits and policy implications, with a view to optimizing the problem of MPs contamination due to mulching.

A Two-Way Street: How Are Yeasts Impacted by Pesticides and How Can They Help Solve Agrochemical Contamination Problems?

Plant-associated yeasts play significant ecological roles within the microbiomes of soils and pollinating insects. In previous studies, we have shown that yeasts can assist pollinators in locating nectar, which is crucial for their nutrition and the reproduction of many angiosperms. Additionally, in soil, yeasts can also act as plant growth promoters. Given the importance of yeasts for plant development, this review first explores the biochemical processes underlying the ecological role of these microorganisms in soil, insects, and in direct association with plants. Based on this premise, we discuss the influence of these relationships on agricultural production, the biological mechanisms through which pesticides negatively affect yeast cells, and how these microorganisms can tolerate widely used agrochemicals. Finally, we address key studies in the literature that support the potential of these microorganisms as bioremediation agents. In this context, we emphasize different experiences with both indigenous and genetically engineered yeasts, which may display enzymes in their surfaces that convert pesticides into less harmful or nontoxic molecules. Our review indicates that yeasts can be effectively harnessed in organic agriculture to promote plant growth and bioremediate contaminated soil or food.

Understanding the Impact of Soil Characteristics and Field Management Strategies on the Degradation of a Sprayable, Biodegradable Polymeric Mulch

The use of non-degradable plastic mulch has become an essential agricultural practice for increasing crop yields, but continued use has led to contamination problems and in some cropping areas decreases in agricultural productivity. The subsequent emergence of biodegradable plastic mulches is a technological solution to these issues, so it is important to understand how different soil characteristics and field management strategies will affect the rate at which these new materials degrade in nature. In this work, a series of lab-scale hydrolytic degradation experiments were conducted to determine how different soil characteristics (type, pH, microbial community composition, and particle size) affected the degradation rate of a sprayable polyester–urethane–urea (PEUU) developed as a biodegradable mulch. The laboratory experiments were coupled with long-term, outdoor, soil degradation studies, carried out in Clayton, Victoria, to build a picture of important factors that can control the rate of PEUU degradation. It was found that temperature and acidity were the most important factors, with increasing temperature and decreasing pH leading to faster degradation. Other important factors affecting the rate of degradation were the composition of the soil microbial community, the mass loading of PEUU on soil, and the degree to which the PEUU was in contact with the soil.

Ozonation as an emerging technique for inactivating microorganisms and mitigating pesticides in apple juice

ABSTRACT Microorganisms and pesticide residues are among the major health concerns associated with food products. Although ozone (O3) is currently being employed in various applications in apple processing, there are few studies investigating the effects of O3 treatments on microorganisms and pesticides in apple juice. The purpose of this study was to investigate the effects of O3 treatment on microorganisms, pesticide residues, and physicochemical properties of apple juice and to compare with that of classical pasteurization. O3 was as effective as pasteurization against E. coli and coliform bacteria; the counts of these microorganisms were below the detectable level after a treatment for 15 min. O3 was also effective in reducing the counts of total aerobic mesophilic bacteria and yeast-mold, but longer treatments were required for total inactivation. All the pesticides investigated were degraded by O3, but at different rates. Reduction rates were quite high (75–100%) for methoxyfenozide, dimethoate, and pyrimethanil, however, acetamiprid and imidacloprid were degraded by only 7.1% and 14.5%, respectively. O3 treatment caused drastic decreases in color and turbidity values, total phenolic content, and antioxidant activity of apple juice. Results revealed that the use of ozone in juice processing has potential as a technological solution to product contamination problem.

Control of bacterial contamination in three types of fish selected from the coastal and inland regions of Tipaza (Algeria)

This study addresses the problem of microbiological contamination in fish sold in the region of Tipaza, where food safety is a growing concern. It aims to assess the contamination levels in three fish species: sardine, mackerel saurale, and bogue. To achieve this, samples were collected and analyzed for total aerobic mesophilic bacteria, thermotolerant coliforms, coagulase-positive Staphylococcus aureus, and Salmonella. The results revealed that all samples contained total aerobic mesophilic bacteria and thermotolerant coliforms within acceptable limits. However, high levels of coagulase-positive Staphylococcus aureus were detected in bogue and saurale samples, indicating unsatisfactory bacteriological quality, particularly in samples from the city of Tipaza. No Salmonella contamination was observed. These findings highlight significant hygiene issues during fish transport and sale, contributing to microbial contamination. The study concludes that improving handling practices is crucial to ensuring fish safety and reducing health risks to consumers.

Photocatalytic Degradation of Four Organic Dyes Present in Water Using ZnO Nanoparticles Synthesized with Green Synthesis Using Ambrosia ambrosioides Leaf and Root Extract

Currently, several organic dyes found in wastewater cause severe contamination problems for flora, fauna, and people in direct contact with them. This research proposes an alternative for the degradation of polluting dyes using ZnO nanoparticles (NPs) synthesized by an ecological route using leaf and root extracts of Ambrosia ambrosioides as a reducing agent (with a weight/volume ratio = 4%). Scanning Electron Microscopy (SEM) was used to determine the morphology, showing an agglomeration of cluster-shaped NPs. Using Transmission Electron Microscopy (TEM), different sizes of NPs ranging from 5 to 56 nm were observed for both synthesized NPs. The composition and structure of the nanomaterial were analyzed by infrared spectroscopy (FT-IR) and X-ray diffraction (XRD), showing as a result that the NPs have a wurtzite-like crystalline structure with crystallite sizes around 32–37 nm for both samples. Additionally, the bandgap of the NPs was calculated using Ultraviolet Visible Spectroscopy (UV–Vis), determining values of 2.82 and 2.70 eV for the NPs synthesized with leaf and root, respectively. Finally, thermogravimetric analysis demonstrated that the nanoparticles contained an organic part after the green synthesis process, with high thermal stability for both samples. Photocatalytic analysis showed that these nanomaterials can degrade four dyes under UV irradiation, reaching 90% degradation for methylene blue (MB), methyl orange (MO) and Congo red (CR) at 60, 100 and 60 min, respectively, while for methyl red (MR) almost 90% degradation was achieved at 140 min of UV irradiation. These results demonstrate that it is effective to use Ambrosia ambrosioides root and leaf extracts as a reducing agent for the formation of ZnO NPs, also evidencing their favorable application in the photocatalytic degradation of these four organic dyes.

Aromaticity of charged cyclocarbon radicals (Cn± = 6–30)

Aromaticity of charged cyclocarbon radicals (Сn±=6–30) have been studied computationally at density functional level of theory based on the magnetically induced ring-current calculations. It was found that the M06-2X functional correctly reproduces the radical structure of charged cyclocarbons, while the BHandHLYP and wB97XD functionals tend to have spin contamination problems. Charged cyclocarbons (n = 6–20) radicals have a pronounced difference in the BLA between n = 4 k/n = 4 k + 2 structures. Charged cyclocarbons (n = 6–22) are characterized by an alternating aromaticity satisfying the n = 4 k/4k + 2 rule. This rule breaks down in predicting the aromaticity of cyclocarbons with n ≥ 24, where the difference in the BLA between n = 4 k/4k + 2 structures disappears.

Sintered Clays: Application in the Removal of Arsenic from Water by Filter Beds

Objectives: The main objective of the research was to build a ceramic filter bed, using red clay and diatomite, for the removal of arsenic in aqueous media and to propose an environmentally friendly and low-cost technique for rural communities in Peru that consume water contaminated with arsenic. Theoretical framework: Arsenic is a common contaminant in the drinking water of many rural communities in Peru, exceeding the limits allowed by the WHO. Prolonged exposure to arsenic can cause serious health problems. The use of low-cost non-metallic materials, such as thermally activated clay and diatomite, is proposed for its adsorption. Method: A filter bed composed of 5 cm layers of red clay and diatomite with particle sizes of 0.81, 0.31 and 0.20 mm was used. Both materials were thermally activated at 900°C and placed on a stainless steel support. The arsenic removal process was evaluated by passing a synthetic solution with 13.99 ppm of arsenic through the bed. Material characterization analyses were performed before and after the adsorption process, using techniques such as ICP-OES, SEM, FTIR, among others. Results and discussion: The filter bed composed of diatomite (83.31% SiO2) and red clay (8.23% Fe2O3) achieved an arsenic removal of up to 99.99%, highlighting the efficiency of particles with a size of 0.20 mm. This shows that the combination of these materials can be highly effective in removing arsenic in water, which is promising for its implementation in rural areas. Research implications: This research has important implications for water treatment in rural communities facing arsenic contamination problems. The technique developed is low-cost and uses abundant resources, which facilitates its application at the local level and promotes sustainable solutions for access to safe drinking water. Originality/Value: The research provides a novel approach through the use of red clay and diatomite, accessible resources, thermally activated for the removal of arsenic in water. In addition, the high removal effectiveness achieved provides a potentially scalable and replicable solution in other rural communities with similar problems.

The Problem of Scale Contamination and Construct Validity in Mental Health, Social Science and Spirituality-Related Research

This article explores the pervasive issue of scale contamination and its impact on construct validity in mental health, social science, and spirituality-related research. Scale contamination occurs when measurement tools designed to assess one specific domain inadvertently incorporate elements from unrelated constructs, leading to confusion regarding what the scale is actually measuring. The blending of distinct psychological domains, such as depression, anxiety and well-being, undermines measurement precision, leading to skewed research conclusions and misguided clinical practices. The failure to detect or address contamination can perpetuate errors in treatment efficacy, particularly in areas such as mental health and spirituality, where precise measurement is crucial. This article emphasizes the importance of ensuring construct validity, which refers to the accurate measurement of specific concepts such as moral injury or posttraumatic stress disorder, and it highlights the risk of conflating distinct constructs. The widespread use of contaminated scales, often adopted without critical evaluation, poses a significant threat to the integrity of research outcomes. In order to address these challenges, this study advocates for rigorous scale development and validation processes, encouraging researchers, peer reviewers and journal editors to scrutinize the psychometric properties of scales. By ensuring that scales measure only the intended constructs, future research can produce more accurate and meaningful results, leading to improved clinical interventions and policy decisions.

Phytoremediation of Hg and chlorpyrifos contaminated soils using Phaseolus vulgaris L. with biochar, mycorrhizae, and compost amendments.

Anthropogenic activities, encompassing vast agricultural and industrial operations around the world, exert substantial pressure on the environment, culminating in profound ecological impacts. These activities exacerbate soil contamination problems with pollutants such as mercury (Hg) and chlorpyrifos (CPF) that are notable for their widespread presence and detrimental effects. The objective of this study is to evaluate the phytoremediation potential of Phaseolus vulgaris L., augmented with various combinations of biochar, mycorrhizal, and compost amendments, as a sustainable alternative for the remediation of soils contaminated with Hg and CPF. For this purpose, soil from a mining area with mercury contamination has been taken, to which CPF has been added in different concentrations. Then, previously germinated Phaseolus vulgaris L. seedlings with an average height of 10cm were planted. Electrical conductivity, pH, organic matter, CPF, and Hg, as well as seedling growth parameters, have been evaluated to determine the processes of absorption of soil contaminants into the plant. A combination of biochar with mycorrhiza has been found to be an optimal choice for CPF and Hg remediation. However, all amendments have proven to be efficient in the remediation processes of the tested contaminants.

Domestic and irrigation water quality on the southern slopes of Mount Kilimanjaro

This study assessed the water quality for drinking and irrigation purposes on the southern slopes of Mt. Kilimanjaro during the dry season under low flow conditions. Fifty-one samples covering eight different water sources (i.e., stream water from natural and anthropogenic impacted streams, domestic water, spring water, rainfall, groundwater, lake water and water from irrigation canals) were collected in a snapshot sampling campaign over 10 days in February 2023. First, physical, chemical and biological parameters were analysed and compared with Tanzanian and international drinking and irrigation water quality requirements. The samples were then ranked according to their suitability for drinking and/or irrigation using water quality indices (WQI). All drinking water quality parameters except for E. coli and turbidity were within the permissible limits. A generalised problem of faecal contamination was found in the study area, including in domestic water, highlighting the need to identify sources of contamination and remediate them before distribution. The drinking water quality index (DWQI) classified 89% of the samples as unsuitable and 11% as excellent for drinking. Irrigation water quality parameters were within the guidelines of restriction of use except for pH in 5 samples. In contrast to the DWQI, the vast majority of the water samples (88%) can be used for irrigation without restrictions according to the irrigation water quality index (IWQI). The suitability of water for irrigation was also assessed using three indices, i.e., Kelley’s Index, Soluble Sodium Percentage and Magnesium Ratio, which indicated potential problems with excess of sodium (about 30% of the samples) and magnesium (about 20%). Further studies combining suitability indices, soil characteristics and crop types are recommended to assess water quality for irrigation use.

Impact of high-speed nanodroplets on various pathogenic bacterial cell walls.

Although existing disinfection techniques demonstrate bactericidal effects through chemical reactions, concerns regarding human toxicity and environmental contamination have been raised. To the best of our knowledge, this study is the first in the world to reveal that the use of this technology, with nanodroplets of less than 100 nm, can destroy and sterilize bacterial cells by colliding with biofilm-forming bacteria at 75 MPa. Furthermore, because this technology uses only water, it can solve the problems of human toxicity and environmental contamination caused by existing disinfection techniques. Because of its minimal water usage, it can be employed for sanitation worldwide without being limited to specific regions. Our report proposes an unprecedented physical disinfection approach that utilizes a high-speed nanodroplet generation technology.

Inactivation kinetics of Bacillus cereus and Aspergillus niger spores in dehydrated onion shreds after pulsed light and infrared treatments

Fresh onions are dehydrated to increase their shelf-life. Primarily, open dehydration techniques like solar dehydration come with the problem of contamination through natural air convection. A solar conduction dryer that uses conduction, convection, and radiation for dehydration of food samples is exploited in this study. The food samples are often contaminated by Bacillus and Aspergillus species spores. As a remedy, pulsed light treatment as a non-thermal technology and infrared treatment as a thermal technology are studied and compared. Bacillus cereus and Aspergillus niger spores are chosen as a representative of bacterial and fungal contamination in onions. Dehydrated onion shreds with varying water activities (0.4, 0.5, 0.6) were treated. The spore inactivation was best described by Weibull model as compared with first-order model. Scanning electron microscopy images of the microbial cells showed surface distortions on the bacterial and fungal spores. The effect of the treatment technologies on the colour, flavour (thiosulphinate and pyruvic acid concentration), total phenolic and flavonoid content, and ascorbic acid concentration are compared. Overall, pulsed light treatment showed promising inactivation with a maximum log reduction of 4.5 log B. cereus spores·g−1 and 3.1 log A. niger spores·g−1 at 2.131 J·cm−2 in samples with water activity 0.6. The inactivation rate increased with an increase in water activity. The colour was better retained in pulsed light treated samples. The thiosulphinate content (9.24 μmol·g−1), total phenolics (0.268 mg GAE·g−1), and flavonoid content (0.344 mg QE·g−1) in the sample were improved upon pulsed light exposure.Graphical

Determination of Tetracycline Group Antibiotics Residues in the Tigris River and Agricultural Lands Fed by Tigris River and Reduction of Unconscious Use of Antibiotics

The recent increase in environmental pollutants is contaminating important natural resources and causing irreversible damage. Due to the limitations of traditional treatment techniques, studies on the problem of micro pollutant contamination of water resources have increased significantly. Antibiotics used in medicine and veterinary medicine cause significant pollution of water resources as residues of these contaminants remain unchanged in the aqueous environment. This has recently been recognised as a global environmental health threat. The ecosystem is vulnerable to residues of these contaminants from agriculture and aquaculture. In this study, the presence of tetracycline group antibiotics, the most commonly used in veterinary medicine, was determined in the Tigris river. This is the first study to date in which antibiotics from the tetracycline group have been identified in the Tigris river. Water samples were taken from 16 different points (80 samples) along the river. Sampling points were grouped as abattoirs, livestock markets, farmland, cafes and bridges near settlements. The samples were analysed for the presence of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC). With a concentration range of 0.037 to 1.756 ng/L, oxytetracycline was found in 14 of the 16 sites. A concentration of 0.004–0.014 ng/L of tetracycline was found in five samples. Chlortetracycline was found in six samples, with concentrations ranging from 0.015 to 0.097 ng/L. According to the study, the tetracycline family of antibiotics was found in the water samples, and oxytetracycline was present in the highest concentrations in most of them.