High Levels Of Contamination Research Articles

Nanopore sequencing for identification and characterization of antimicrobial-resistant Escherichia coli and Salmonella spp. from tilapia and shrimp sold at wet markets in Dhaka, Bangladesh.

Wet markets in low-and middle-income countries are often reported to have inadequate sanitation resulting in fecal contamination of sold produce. Consumption of contaminated wet market-sourced foods has been linked to individual illness and disease outbreaks. This pilot study, conducted in two major wet markets in Dhaka city, Bangladesh during a 4-month period in 2021 aimed to assess the occurrence and characteristics of Escherichia coli and non-typhoidal Salmonella spp. (NTS) from tilapia (Oreochromis niloticus) and shrimp (Penaeus monodon). Fifty-four individuals of each species were collected. The identity of the bacterial isolates was confirmed by PCR and their susceptibility toward 15 antimicrobials was tested by disk diffusion. The whole genome of 15 E. coli and nine Salmonella spp. were sequenced using Oxford Nanopore Technology. E. coli was present in 60-74% of tilapia muscle tissue and 41-44% of shrimp muscle tissue. Salmonella spp. was found in skin (29%) and gills (26%) of tilapia, and occasionally in muscle and intestinal samples of shrimp. The E. coli had several Multilocus sequence typing and serotypes and limited antimicrobial resistance (AMR) determinants, such as point mutations on glpT and pmrB. One E. coli (BD17) from tilapia carried resistance genes for beta-lactams, quinolones, and tetracycline. All the E. coli belonged to commensal phylogroups B1 and A and showed no Shiga-toxin and other virulence genes, confirming their commensal non-pathogenic status. Among the Salmonella isolates, five belonged to Kentucky serovar and had similar AMR genes and phenotypic resistance patterns. Three strains of this serovar were ST198, often associated with human disease, carried the same resistance genes, and were genetically related to strains from the region. The two undetermined sequence types of S. Kentucky were distantly related and positioned in a separate phylogenetic clade. Two Brunei serovar isolates, one Augustenborg isolate, and one Hartford isolate showed different resistance profiles. This study revealed high fecal contamination levels in tilapia and shrimp sold at two main wet markets in Dhaka. Together with the occurrence of Salmonella spp., including S. Kentucky ST198, a well-known human pathogen, these results stress the need to improve hygienic practices and sanitation standards at markets to improve food safety and protect consumer health.

Identification of toxic metal contamination in surface sediments of the Xiaoqing River under a long-term perspective (1996–2020): Risks, sources and driving factors

The contamination of sediments by toxic metals poses a significant threat to both river ecosystems and human health. In this study, the geo-accumulation index (Igeo), biotoxicity evaluation method, and potential ecological risk index (RI) were employed to analyze the contamination level, biotoxicity risk, and potential ecological risk of toxic metals in surface sediments of the Xiaoqing River. To identify toxic metal sources, Spearman correlation and principal component analysis with multiple linear regression analysis (PCA−MLR) were employed. Additionally, redundancy analysis (RDA) was utilized to investigate potential driving factors affecting toxic metal accumulation in sediments. The results revealed that the levels of the five investigated metals (Cr, Pb, As, Hg, and Cd) showed constant fluctuations during the period 1996–2020. The midstream was found to be more polluted than the upstream and downstream. In the research area, Hg was identified as the primary contaminant with high levels of contamination, posing a biotoxicity risk and potential ecological risk. Pollution sources were identified for two periods: A (1996–2010) and B (2011–2020), with industrial, agricultural, traffic, and natural sources being the main contributors. During period A, industrial sources accounted for the highest proportion (40.8%), followed by agricultural sources (36.6%), and geological natural sources (22.6%). During period B, agricultural sources accounted for the highest proportion (42%), followed by industrial and traffic sources (32.4%), and geological natural sources (25.6%). The distribution of toxic metals in the basin was significantly influenced by water pH, sediment organic matter, population density, and per capita GDP. The study results provide fundamental data for preventing pollution and managing water resources contaminated with toxic metals in the sediments of the Xiaoqing River in Jinan. Additionally, it serves as a reference for analyzing related ecological and environmental issues in the basin.

Impact of lead and zinc heavy metal pollution on the growth and phytoremediation potential of Sulla carnosa in Sebkha el Kalbia, Tunisia.

Heavy metal pollution from human and natural activities poses significant environmental and health concerns for wildlife and humans, with lead and zinc being particularly threatening. This study focuses on Sebkha el Kalbia in Tunisia, highlighting the challenges faced by local communities in addressing heavy metal pollution. The area is prone to contamination through rivers and streams that transport pollutants from industrial zones and rural areas into the salt pan. The recent establishment of an industrial zone has worsened pollution levels, calling for strict regulatory measures and clean technologies to limit heavy metal pollution and protect human health and the environment. The study assesses the impact of lead and zinc pollution on the growth of Sulla carnosa and its potential for phytoremediation. Soil and plant samples from contaminated areas were analyzed, revealing high levels of heavy metal contamination. The growth parameters of Sulla carnosa, such as plant height, weight, and enzymatic activity, were examined, showing a significant reduction in plant growth when exposed to high metal concentrations. Specifically, in the presence of 100ppm of lead (Pb), net photosynthetic assimilation (An) decreased by 52%, while the amount of Pb increased by 78%. At 800ppm of Pb, An decreased by 87%, and the amount of Pb increased by over 800%. Furthermore, the relationship between net photosynthetic assimilation and lead (Pb) content remained significant but negative. At high doses (800ppm), the biomass produced decreases by 64%, while the amount of Zn increases 2.7 times. These results suggest that at low doses, zinc is not toxic. These findings highlight Sulla carnosa as a potential candidate for phytoremediation with preferential metal accumulation in the roots and improved enzymatic activity, underscoring the urgency of addressing heavy metal pollution in Sebkha el Kalbia.

The effect of parica seed water immersion time on the success of parica seed initiation (Schizolobium amazonicum Huber ex Ducke)

Parica culture has the potential to overcome problems in parica seed germination. One factor that influences the successful initiation of parica culture is the process of sterilization and pre-treatment in the form of breaking seed dormancy. This paper aims to analyze the effect of the immersion time of parica seeds on the germination rate of parica seeds. The explants used were parica seeds with a size of ± 2 cm. Seeds are given pre-treatment, the seeds are immersed in hot water at around 70°C for 10 minutes, the immersion time in hot water is 3, 6, 12, and 24 hours according to treatment. The variables observed were the first time the parica seeds germinated, the percentage of germinated seeds, the percentage of contamination (fungi, bacteria), and the percentage of browning. The results showed that the immersion time for pre-treatment affected the success of parica seed initiation, especially seed germination. The 3-hour immersion treatment used resulted in the highest germination of parica seeds (55%) and significantly differed from the germination rates in other immersion times. Based on the high germination rate and low level of contamination, this becomes prospectively to provide optimal in vitro parica germination.

Assessing the role of individual foxes in environmental contamination with Echinococcus multilocularis through faecal samples

Key parasite transmission parameters are difficult to obtain from elusive wild animals. For Echinococcus multilocularis, the causative agent of alveolar echinococcosis (AE), the red fox is responsible for most of the environmental contamination in Europe. The identification of individual spreaders of E. multilocularis environmental contamination is crucial to improving our understanding of the ecology of parasite transmission in areas of high endemicity and optimising the effectiveness of prevention and control measures in the field. Genetic faecal sampling appears to be a feasible method to gain information about the faecal deposition of individual animals. We conducted a 4 year faecal sampling study in a village that is highly endemic for E. multilocularis, to assess the feasibility of individual identification and sexing of foxes to describe individual infection patterns. Individual fox identification from faecal samples was performed by obtaining reliable genotypes from 14 microsatellites and one sex locus, coupled with the detection of E. multilocularis DNA, first using captive foxes and then by environmental sampling. From a collection of 386 fox stools collected between 2017 and 2020, tested for the presence of E. multilocularis DNA, 180 were selected and 124 samples were successfully genotyped (68.9%). In total, 45 unique individual foxes were identified and 26 associated with at least one sample which tested positive for E. multilocularis (Em(+)). Estimation of the population size showed the fox population to be between 29 and 34 individuals for a given year and 67 individuals over 4 years. One-third of infected individuals (9/26 Em(+) foxes) deposited 2/3 of the faeces which tested positive for E. multilocularis (36/60 Em(+) stools). Genetic investigation showed a significantly higher average number of multiple stools for females than males, suggesting that the two sexes potentially defecated unequally in the studied area. Three partially overlapping clusters of fox faeces were found, with one cluster concentrating 2/3 of the total E. multilocularis-positive faeces. Based on these findings, we estimated that 12.5 million E. multilocularis eggs were produced during the study period, emphasizing the high contamination level of the environment and the risk of exposure faced by the parasite hosts.

Antimicrobial Resistance and Sports: The Scope of the Problem, Implications for Athletes' Health and Avenues for Collaborative Public Health Action.

Antimicrobial resistance (AMR) poses a global threat, leading to increased mortality and necessitating urgent action-however, its impact on athletes and the world of sports has hitherto been neglected. Sports environments (including athletic and aquatic) exhibit high levels of microbial contamination, potentially contributing to the spread of resistant microorganisms during physical activities. Moreover, the literature suggests that travel for sports events may lead to changes in athletes' gut microbiomes and potentially impact their antibiotic resistance profiles, raising questions about the broader implications for individual and public/global health. The prevalence of Staphylococcus aureus (S. aureus) among athletes (particularly those engaged in contact or collision sports) ranges between 22.4% and 68.6%, with MRSA strains being isolated in up to 34.9% of tested individuals. Factors such as training frequency, equipment sharing, delayed post-training showers, and a history of certain medical conditions are linked to higher colonization rates. Moreover, MRSA outbreaks have been documented in sports teams previously, highlighting the importance of implementing preventive measures and hygiene protocols in athletic settings. In light of the growing threat of AMR, there is a critical need for evidence-based treatment guidelines tailored to athletes' unique physiological demands to ensure responsible antibiotic use and mitigate potential health risks. While various initiatives-such as incorporating AMR awareness into major sporting events-aim to leverage the broad audience of sports to communicate the importance of addressing AMR, proactive measures (including improved AMR surveillance during large sporting events) will be indispensable for enhancing preparedness and safeguarding both athletes' and the general public's health. This narrative review thoroughly assesses the existing literature on AMR and antibiotic usage in the context of sports, aiming to illuminate areas where information may be lacking and underscoring the significance of promoting global awareness about AMR through sports.

Effects of carboxymethyl starch as a papermaking additive

Carboxymethyl starch (CMS) is a bio-based, anionic polymer that has potential as part of a dry-strength additive program for papermaking. Due to its negative charge, its effects can be expected to depend on its interactions with various cationic agents. In this work, the effects of CMS were observed following its sequential addition after one of three selected cationic strength agents at different dosage levels. In selected tests, the furnish was pretreated at the 1% level by a dispersant, sodium polyacrylate, which might represent a high level of anionic contaminants in a paper mill system. Laboratory tests were conducted to show the effects on dewatering, fine-particle retention, and flocculation. These tests were supplemented with measurements of charge demand, zeta potential, and handsheet properties. Sequential addition of cationic glyoxylated acrylamide copolymers (gPAM) and CMS were found to strongly promote dewatering. Two gPAM products and a poly(vinylamine) product in sequential addition with CMS were very effective for promoting fine-particle retention. These same sequential treatments of the stock contributed to moderate fiber flocculation, though severe flocculation was caused by further treatment of the furnish with colloidal silica. Handsheet strength results were mixed. In the default recycled copy paper furnish, the average breaking length for the sheets made with cationic additives followed by CMS was not greatly different from the blank condition. Superior strength resulted when the default furnish was treated with a dispersant alone. When the dispersant-contaminated furnish was treated with the same combinations of cationic additives and CMS, the strength returned to the baseline achieved in the absence of the dispersant. The results were discussed in terms of the charged character of the different additives and their interactions not only with the fiber surfaces but also with each other.

Risk assessment and pollution loads of potentially toxic elements in water of four rivers flowing into the Mediterranean Sea

One of the main sources of metal accumulation in the marine environment is transport by rivers. Using data from 2014 to 2017 for various stations, this study analysed the distribution of potential toxic element (PTE) concentrations in surface waters, the pollution loads and the water quality index of the large rivers flowing into the Mediterranean Sea (Manavgat, Göksu, Seyhan and Ceyhan). 13 different elements (As, Cd, Cr, Co, Cu, Fe,Pb, Li, Mn, Ni, Se, Zn, Al) were determined within the scope of the study. While the estimation of risk assessments for both adults and children via dermal and ingestion pathways using the United States Environmental Agency (USEPA) formulas. Pollution indexes such as Chronic daily intake (CDI), hazard quotient (HQ), hazard index (HI) and carcinogenic risk (CR) were calculated. Additionally, water quality index (WQI), pollution load ındex (PLI) and contamination factors (CF) were also determined. Since it is a detailed monitoring study of three years, all findings are evaluated using average values for each river. The highest mean PTE concentrations across all rivers were found at stations S4 (Seyhan), S1 and M1 (Manavgat) with Ni (0.1895) > Se (0.0618) > Al (0.0598), respectively. The values of PLI were found to be generally high (3−6) and very high (>6) in all studied rivers. Additionally, these rivers are subject to significant contamination with Pb, as CF>5, indicating very high levels of contamination, was found as a minimum of 166 for Pb in all rivers. Considering all risk assessments, it is concluded that children are more sensitive to ingestion and dermal exposure pathways than adults, and their carcinogenic risk is 4.5 times greater than adults. Besides, according to the statistical analysis, the strong and weak correlation of Al with other elements indicates that the source of the pollution is natural and anthropogenic processes, respectively.

Determinants of Performance for Robotics Teleoperated Activities: From Emergency Response to Decommissioning

After the nuclear accidents of Chernobyl and Fukushima, several countries concerned with nuclear energy production set up robotic accident intervention groups with the aim to intervene in place of humans in hostile environments with high levels of contamination or irradiation. It is the case of France. The operational feedback of such robotic groups may be of interest for teams performing decommissioning on nuclear facilities. In this aim, a comparative analysis of robotic intervention contexts was undertaken between training contexts and a real operating situation. This allowed us to confirm determinants of performance already identified in the literature and highlighted new determinants of performance for intervention in nuclear environments.

Contamination levels of potentially toxic elements within the Ogun River estuary sediments, southwest Nigeria: Ecological and human health risk assessments

BackgroundThe Ogun River estuary is located at the northwestern corner of the Lagos Lagoon in southwest Nigeria. Metal smelting, petroleum products transport, sewage disposal and chemical production are activities within this region, which could lead to the release of potentially toxic elements (PTEs) into the immediate environment. This study investigates the contamination levels of PTEs in the Ogun River estuary sediments, with emphasis on ecological and human health risks. MethodsFourteen sediment samples were collected from the estuary through the Ogun River and Majidun environments. These samples were analyzed for PTEs including Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). The contamination levels of sedimented PTEs from selected sample sites in the estuary were documented for ecological and health risk assessments. ResultsThe analysis revealed bulk concentrations of PTEs across the sampling stations. The contamination factor (CF) showed high contamination levels for Cd and Zn at sample sites 2, 14 and 16; while the other metals revealed moderate pollution indices across all the sites. The risk factor (Er) values of Cd at stations 2, 15 and 16 showed potential contamination. The canonical correspondence analysis (CCA) signified that the distribution of the PTEs is independent of the environmental factors, exposing significant anthropogenic input. Evaluations of the sediment quality revealed that PTEs such as Cd, Cu, Ni, Pb, and Zn, whose concentrations are above their TECs and ERLs, have little to no detrimental effects on sediment living organisms. The health risk assessment has shown that HI values for the elements fall within the non-carcinogenic risk range. The effects of the mean concentrations of these metals on the non-carcinogenic risk (HQ) for adults and children in decreasing order of impact are Co > Pb > Mn > Ni > Cd > Cu > Zn > Fe for both ingestion and dermal pathways. The human health risk index varies from low cancer risk in adult (LCR = 4.4 × 10−5) to moderate cancer risk in children (LCR = 4.1 × 10−4). ConclusionThis study has revealed the significance of anthropogenic input of PTEs into the environment. The sedimented PTEs are within permissible range, but monitoring and assessment activities should be focused on the Majidun axis since most metals show high concentration in this region.

EFFECT OF 137CS ON FATTY ACID COMPOSITION IN COW`S MILK

Lipid composition of raw milk is a key factor determining the nutritional value and technological suitability of the milk. Monitoring the level of contamination of cow’s milk is often not available for farmers, living in the zone of radioactive contamination. 137Cs activity concentration was higher than permissible level of 100 Bq/kg in all the studied milk samples from all the experimental groups of animals from the studied settlements. The highest value of the 137Cs activity concentration of 600 Bk/kg in cow’s milk was found in Stare Selo village of Rokytne district. According to our study, local animals have partially adapted to the seasonal increase in background radiation, and the milk of these cows, in accordance with existing quality standards, is conditionally suitable for consumption. The only factor prohibiting the consumption of this milk is the level of cesium-137 contamination. An increase in the 137Cs activity concentration of more than 100 Bq/kg in cow’s milk causes a sharp decrease in the relative content of polyunsaturated fatty acids (mostly of omega-6 fatty acids) and changes in the omega-3/omega-6 ratio downward omega-3 relative content. Relative adaptation of the lactating cows to the contamination was revealed; however, metabolism of lipids in the mammary gland and the level of lipids secretion are found to be sensitive to the level of 137Cs contamination of milk. Thus, a violation of the secretory function of the mammary gland was revealed, in particular, metabolism of lipids with 18 carbon atoms in the chain. Relative content of linoleic acid immediately decreases by several times with the increasing the contamination level. Concentration of the stearic acid immediately exceeds the physiological limits at the value of 137Cs activity concentration in milk about 110–130 Bq/kg. It gradually increases with the increasing the 137Cs activity concentration up to 270–330 Bq/kg. And then it is being plateaued with the increasing the 137Cs activity concentration up to 600 Bq/kg. On the base of the study of effect of 137Cs on fatty acid ratio in cow’s milk, the C18-coefficient is being proposed to be used as the parameter of damage to the mammary gland of cows in response to a high level of 137Cs contamination, which is calculated as follows: C18c = (C18:0–C18:2)/100). Determination of the C18-coefficient indicates the dose-dependent effect of the 137Cs contamination on lipid metabolism in the mammary gland and catabolism of polyunsaturated fatty acids, particularly linoleic acid. Duration of the affecting contamination is obviously decisive factor of damage effect to the mammary gland, defining the level of biochemical transformations and initiating of peroxide processes.

High Levels of Fungal and Aflatoxin Contamination of the Production Stages of the Local Brew (Ajono) consumed in Uganda

Local brew commonly known as Ajono is a widely consumed alcoholic beverage in Uganda. Handling practices along the production stages of the local brews may create a conducive environment for fungal colonization. This study aimed to assess fungal and aflatoxin contamination along the different production stages of Ajono from Soroti District in Eastern Uganda. A total of 180 samples were collected from the different stages along Ajono production. An interview guide was used to assess the processing practices while fungal contamination was assessed using standard microbiological methods. The study found that there are three main stages during Ajono production, namely; millet grain, fermented paste, and the liquid (Ajono) stages. During the paste fermentation stage, brewers used plastic drums (50%), pits (47%) or pots (3%) as fermentation vessels. Samples from plastic drum fermentation vessels had higher levels of fungal contamination than those from the pits and pots. Furthermore, several moulds genera including Aspergillus spp., Fusarium spp., Alternaria spp., Rhizopus spp., Penicillium spp., Cladosporium spp., and Acremonium spp. were identified along the production stages, with Aspergillus spp. as the most prevalent moulds at all stages of Ajono production. Two yeast genera; Saccharomyces spp. and Candida spp. were also isolated. Total Aflatoxin B and G group was detected along the production stages of Ajono with the highest prevalence (78.6%) seen in the liquid Ajono from pit fermenters and 68.8% in drum fermenters. Overall, all three stages of Ajono production; millet grain, fermented paste, and the liquid Ajono stages were highly contaminated with aflatoxigenic fungi which may cause adverse health effects under continued and sustained consumption of the brew

Indication of Phages and Their Role in the Regulation of the Purification Process at the Govsany Aeration Station in Baku

Due to the epidemic situation and the emergence of enteroviral diseases, we set ourselves the task of conducting comprehensive virological and bacteriological studies of the wastewater, its sludge and contaminated soil from the Govsany aeration station. The fact of constant detection of enteroviruses in samples of wastewater and soil in combination with bacteriophages is considered by us as a possibility of detection of bacteriophages at WWTP sites. The 26 wastewater samples contain enteroviruses at various stages of treatment, 18 of which were characterised by high levels of faecal contamination (thermoletarian coliforms), C. perfringens and Enterococcus faecalis. In samples with high contamination (TCB up to 106 per 100 ml of wastewater), which are potentially dangerous in terms of the content of infectious disease pathogens, both bacterial and viral, the number of coliphages was below the norm. Consequently, coliphages cannot be used as a sanitary indicator of microorganisms of viral contamination. Intestinal phages are common where humans and animals live and therefore intestinal bacteria are present. Coliphages (bacteriophages) can be formed from lysogenic enterobacteria during the process of stepwise wastewater treatment at the Govsany WWTP.

Soil quality in the urban gardens of Barcelona (Spain)

PurposeUrban agriculture is expanding worldwide and is being promoted by the FAO as a strategic activity because of its environmental, socio-economic, and educational benefits for citizens. In Spain, it is estimated that there are more than 20,000 urban gardens. There are many variables to take into account when starting to cultivate an urban garden, among which the quality of the soil is crucial. Nevertheless, some studies have shown high levels of contamination in soils dedicated to urban horticulture. The sources of contamination can be various, such as previous unrecognized management and irrigation with poor quality water, or the addition of polluted compost and other soil improvers. Soil contamination can migrate to vegetables and fruits, thus entering the food chain.Materials and methodsIn this study, we analyzed the soils from ten urban gardens in the city of Barcelona, with a special focus on possible contaminants. Based on the possibility that irrigation water is a source of pollution, this was also analyzed in all investigated gardens.Results and discussionSome of the waters analyzed for irrigation have a high concentration of salts, and a few of them contain nitrites, which are listed as a pollutant. The dominant texture of the soils was sandy clay loam and loamy sand, the pH was generally high, between 7.87 and 8.41, clearly carbonated, with Ca generally being the dominant exchangeable cation, but without the risk of a high percentage of active carbonates that could make it difficult to grow vegetables. The content in organic matter was very variable, but in all cases it appeared to be potentially incrementable. The three tests used to check possible soil contamination from heavy metals, do not attest to significant pollution.ConclusionsThe soil quality overall is suitable for growing vegetables and allowing growers to work in these areas in complete safety. Although it would be necessary to analyze also other toxic elements, not considered in this study, some of the measured ones could come from the gases of road transport or even from the port of Barcelona.

Higher heavy metal contamination indoors than outdoors during COVID-19 in Mexico City

People spend most of their time indoors, especially during the coronavirus disease. Prolonged exposure to heavy metal-contaminated dust can be harmful to human health. The objectives of this study were to identify the contamination level in outdoor and indoor dust, compare contamination in both environments, and assess the human health risk. Two-hundred thirty-nine samples of dust were taken by Mexico City citizens in 38 homes on the weekends of May 2020. Heavy metal concentrations were measured through XRF. The contamination level was set using the contamination factor with a local and global background value, mixed linear models were used to identify indoor and outdoor differences, and USEPA human health risk methodology was used. Pb, Zn, and Cu had the highest contamination levels, followed by Sr and Mn, using both the local and global background values. The Pb, Zn, and Cu contamination was greater indoors, while higher Mn, Sr, and Fe were detected outdoors. According to the outdoor/indoor ratios, the main sources of Ca, Pb, Zn, and Cu must be indoors, while the main sources of Fe, Mn, Sr, Y, and Ti are outdoors. A human health risk was not detected, as the hazard index was lower than one. However, ailments can be developed due to exposure to Pb, Mn, and Fe in children (hazard index > 0.1). A higher risk due to Pb exposition was found indoors. Indoor environments in Mexico City were more contaminated by heavy metals and represented a higher risk to human health than outdoors during the pandemic isolation.

Effect of some physicochemical parameters on the decay rate of enteric bacteria isolated from River Owena, Nigeria

The significance of water in public health cannot be overemphasized. In Nigeria, many people living along the courses of water bodies still source and drink from the rivers and streams. There is, therefore, the need to determine the load of contamination and effect of pH and salinity on the decay rate of enteric bacteria in water samples from River Owena, Owena, Nigeria, in order to develop adequate water quality management. Water samples from River Owena were collected from three sampling points (inflow, middle course and the outflow) along the River Owena, Nigeria. The load of enteric bacteria in the water samples was enumerated using membrane filtration technique. The physicochemical parameters of the water samples were determined using standard methods. The incidence and prevalence of gastroenteritis in the community around River Owena was determined using a structured questionnaire. Microcosm studies were used to determine the decay rate of enteric bacteria at varying salinity and pH. Canonical correlation analysis was used to describe the relationship between the load of enteric bacteria and the incidence and prevalence of gastroenteritis in the community around River Owena. The incidence and prevalence of gastroenteritis in the community around River Owena were estimated to be 0.75 and 0.51, respectively. Escherichia coli had positive relationships with incidence (r = 0.76) and prevalence (r = 0.65). Similarly, faecal coliforms had positive relationships with incidence (r = 0.82) and prevalence of gastroenteritis (r = 0.67), while enterococci showed positive relationship with incidence (r = 0.59) and prevalence of gastroenteritis (r = 0.87). Increase in pH and salinity increased the decay rate of enteric bacteria thereby reducing the growth of enteric bacteria, the optimum pH for the growth and survival of enteric bacteria ranged between pH 5.0 and pH 7.0. The optimum salinity for the growth of enteric bacteria isolated in water samples from River Owena ranged between 10 and 50% salinity. Findings revealed high levels of faecal contamination at the different representative monitoring points on River Owena, pH and salinity influenced the load and decay rate of enteric bacteria in water from River Owena.

A Cross-sectional Study to Assess Bacteriological Quality of Fresh Vegetable Salads and Associated Risk Factors in Food Service Establishments in Mwanza City

This study examined the bacteriological quality of fresh vegetable salads and associated risk factors in restaurants and street food vendors in Nyamagana and Ilemela municipalities, Mwanza City, Tanzania. Thirty samples of vegetable salads (i.e., Kachumbari), along with 30 swabs from hands and chopping boards, were collected and analyzed. High contamination levels exceeding acceptable limits were observed with total bacterial counts, S. aureus, and E. coli ranging from 3.6 to 6.7 log CFU/g. All Kachumbari samples (100%) were unsatisfactory, and 17 (56.7%) had unsatisfactory E. coli levels. Moreover, 22 samples (73.3%) had unsatisfactory S. aureus levels, and 10 samples (33.3%) showed unsatisfactory Salmonella spp. contamination. Further, Kachumbari from street food vending sites had a significantly (p < 0.05) higher TBC mean value (6.5 ± 0.3 log CFU/g) than the one from restaurants (5.2 ± 0.6 log CFU/g). On the other hand, chopping boards and hands had high total counts ranging from 3.5 to 4.7 log CFU.cm-2. Also, the type of chopping board was significantly related to the S. aureus contamination levels in the Kachumbari salads (p < 0.05). The presence of both hygiene indicator microorganisms and pathogens indicates a potential public health risk associated with the consumption of Kachumbari. Urgent intervention measures are required to enhance handling practices, personal hygiene, and overall safety throughout the food value chain, thus ensuring the quality and safety of vegetable salads in food service establishments.

Contamination of Kazakhstan cheeses originating from Escherichia coli and its resistance to antimicrobial drugs

Background and Aim: Escherichia coli, a commensal intestine bacterium of vertebrates, is widely distributed in the environment and indicates the microbiological quality of food products in relation to coliforms. In addition, virulent strains, particularly E. coli O157:H7, cause outbreaks of toxic infections caused by consuming dairy products. Because food safety studies regarding E. coli have not been conducted in Central Asia, this research aimed to study the characteristics of contamination, microbiological and genotypic properties, and resistance to antimicrobial agents of E. coli strains that contaminate various types of commercialized cheeses originating from Kazakhstan. Materials and Methods: In retail outlets, 207 samples of three types of cheese produced by 22 industrial and eight small enterprises in the central, eastern, southern, and northern regions of Kazakhstan were selected in 2020–2023. E. coli contamination was examined using standard microbiological, mass spectrometric, and molecular genetic methods. The discodiffuse European Committee on Antimicrobial Susceptibility Testing method was used to test the resistance of the identified E. coli isolates (65/207; 31.4%) to 20 antibacterial drugs. The Shiga toxin-producing E. coli (VT1 and VT2) and E. coli O157:H7 (eae) genes were investigated in all E. coli isolates using multiplex polymerase chain reaction. Results: An average of 31.4% samples of commercial Kazakhstani cheeses of various types were found to be contaminated with E. coli in almost all geographical regions of Kazakhstan, regardless of the productivity of the dairy enterprises. Soft cheeses produced by small farms (80% of samples) packaged at the retail site (100%) were the most contaminated with E. coli. The microbiological index (colony-forming unit/g) was unsatisfactory and unsuitable in 6.2% of such cheese samples. For the first time in Central Asia, the enteropathogenic strain E. coli O157:H7 was detected in 0.5% of cheese samples. E. coli isolates from cheese samples were resistant to 65% of antibacterial drugs and contained resistance genes to β-lactams, sulfonamides, and quinolones groups. At the same time, 25% of the E. coli isolates were multi-resistant to three or more antimicrobial agents. Conclusion: The high level of contamination caused by multi-antibiotic resistant E. coli strains, including pathogenic pathogens, poses a risk to public health and highlights the need for further research on the monitoring and control of coliform enteropathogens in food products. Keywords: antibiotic resistance, Escherichia coli O157:H7, Kazakhstan cheese, microbial contamination.

Critical Review on Metal‐Based Cosmetic Products

AbstractMost people utilize cosmetics to enhance or improve their physical appearance, regardless of their gender, race, or age. Heavy metals (HMs) are impurities or ingredients in many cosmetic products. According to recent studies, these metals can result in a variety of skin and health issues. Numerous studies demonstrate that the mismanaged formulation of such products without sufficient standardization of toxic metals throughout the production process is the primary reason for the high level of HM contamination in the samples. In order to prevent human exposure to such dangerous HMs, it is vital to monitor and manage the fate of HMs in cosmetic items, especially unbranded ones. Due to the wasteful interest of producers in making extra profit, the standards are not being imposed. Moreover, consumers are also ready to compromise with the product due to their unawareness of its hazardous impact on their skin and bodies. Short‐term results on their looks may cause fatal effects on their health. Another significant issue that requires attention is the lack of safety regulations in the country for evaluating HMs in cosmetic products. Additionally, there is an urgent need to establish acceptable limits for potential impurities in cosmetic products that must be enforced at local levels. This review provides a comprehensive insight into the content of HMs in cosmetics and their effects on several organs and the site of application.

Bacteriological Contamination Level of Foods and Water Sold With Escherichia Coli, Salmonella spp, Staphylococcus Aureus, Coliforms and Vibrio Cholera in Food Establishments in Nairobi City Kenya

Purpose: Food borne illnesses are major health burden leading to high morbidity and mortality. It is a growing public health concerns worldwide resulting from food and water contaminated by pathogenic microorganism, toxins or chemical hazards. It is estimated that 10 to 20% of food borne illness are contracted from food establishments. The main aim was to determine bacteriological contamination levels of foods and water sold with Escherichia coli, Salmonella spp, Staphylococcus aureus, coliforms and Vibrio cholerae in food establishments in Embakasi South Nairobi City County Kenya.
 Methodology: The study design was descriptive analytical design. The Samples were collected in selected food establishments (Cafeteria, Hotels, Restaurants and food Kiosks) in Embakasi South Sub county Nairobi City County. The study collected 274 samples of food and water randomly sampled and collected using sterile food bags and water bottles within selected establishments and transported to the laboratory in cool boxes packed with ice packs. The samples were analyzed within 6 hours after collection. Microbiological analysis of food and water were borrowed from WHO and bacteriological analytical manual of foods to identify and isolate coliforms, Staphylococcus aureus, Vibrio cholera, Escherichia coli and Salmonella spp.
 Results: It was found that some foods and water sold and consumed in the selected food establishments was contaminated with food borne microorganisms. Escherichia coli isolated in 137 food samples were at 24.1%, Vibrio cholera at 23.4%, Staphylococcus aureus at 32.8%, and Salmonella spp at 4.4%. Total coliforms detected in 137 samples of water were at 43.8% where 32.8% of them were Escherichia coli.
 Unique Contribution to Theory, Practice and Policy: The study concluded there was high level of bacterial contamination of foods and water consumed in selected foods establishments. Nairobi City County health officers should enhance regular sampling of foods and water for microbial quality, health education on sources of food contamination at food eateries and establishments to prevent food and water contamination which later lead to food borne illness outbreak.