Preliminary construction of a microecological evaluation model for uranium-contaminated soil.

With the extensive development of nuclear energy, soil uranium contamination has become an increasingly prominent problem. The development of evaluation systems for various uranium contamination levels and soil microhabitats is critical. In this study, the effects of uranium contamination on the carbon source metabolic capacity and microbial community structure of soil microbial communities were investigated using Biolog microplate technology and high-throughput sequencing, and the responses of soil biochemical properties to uranium were also analyzed. Then, ten key biological indicators as reliable input variables, including arylsulfatase, biomass nitrogen, metabolic entropy, microbial entropy, Simpson, Shannon, McIntosh, Nocardioides, Lysobacter, and Mycoleptodisus, were screened by random forest (RF), Boruta, and grey relational analysis (GRA). The optimal uranium-contaminated soil microbiological evaluation model was obtained by comparing the performance of three evaluation methods: partial least squares regression (PLS), support vector regression (SVR), and improved particle algorithm (IPSO-SVR). Consequently, partial least squares regression (PLS) has a higher R2 (0.932) and a lower RMSE value (0.214) compared to the other. This research provides a new evaluation method to describe the relationship between soil ecological effects and biological indicators under nuclear contamination.

Influence of bioaugmented fungi on tolerance, growth and phytoremediation ability of Prosopis juliflora Sw. DC in heavy metal-polluted landfill soil.

The research aimed to determine the influence of endophytic fungi on tolerance, growth and phytoremediation ability of Prosopis juliflora in heavy metal-polluted landfill soil. A consortium of 13 fungal isolates as well as Prosopis juliflora Sw. DC was used to decontaminate heavy metal-polluted landfill soil. Enhanced plant growth (biomass and root and shoot lengths) and production of carotenoids, chlorophyll and amino acids L-phenylalanine and L-leucine that are known to enhance growth were found in the treated P. juliflora. Better accumulations of heavy metals were observed in fungi-treated P. juliflora over the untreated one. An upregulated activity of peroxidase, catalase and ascorbate peroxidase was recorded in fungi-treated P. juliflora. Additionally, other metabolites, such as glutathione, 3,5,7,2',5'-pentahydroxyflavone, 5,2'-dihydroxyflavone and 5,7,2',3'-tetrahydroxyflavone, and small peptides, which include Lys Gln Ile, Ser Arg Ala, Asp Arg Gly, Arg Ser Ser, His His Arg, Arg Thr Glu, Thr Arg Asp and Ser Pro Arg, were also detected. These provide defence supports to P. juliflora against toxic metals. Inoculating the plant with the fungi improved its growth, metal accumulation as well as tolerance against heavy metal toxicity. Such a combination can be used as an effective strategy for the bioremediation of metal-polluted soil.

Multiresidue analysis of bat guano using GC-MS/MS.

Bats are the second largest mammalian order and are an endangered species group with a strong need for contamination monitoring. To facilitate non-invasive monitoring of the ecological burden in bat populations, a multiresidue method for the simultaneous quantification of 119 analytes including pesticides, persistent organic pollutants (POPs), active pharmaceutical ingredients (APIs), polycyclic aromatic hydrocarbons (PAHs), UV blockers, plasticizers, and other emerging pollutants in bat guano with gas chromatography tandem mass spectrometry (GC-MS/MS) was developed. Sample preparation and clean-up were performed with a modified QuEChERS approach based on DIN EN 15662. The method uses 1.00 g bat guano as sample with acetonitrile and water for liquid-liquid extraction. Phase separation is assisted by citrate-buffered salting out agent. For clean-up of the extract, primary secondary amine (PSA) was combined with graphitized carbon black (GCB). The lower limits of quantification (LLOQ) ranged between 2.5 and 250 µg kg-1. Linearity was shown in a concentration range from the respective LLOQs to 1250 µg kg-1. The median of the mean recovery was 102.4%. Precision was tested at three concentrations. Method and injection precision were adequate with a relative standard deviation (RSD) below 20%. Furthermore, the comparative analysis with LC-MS/MS demonstrated the reliability of the results and provided a valuable extension of the analytical scope. As proof of concept, three guano samples from a German nursery roost of Myotis myotis were analysed. The results show a time-dependent change in contaminant concentration, highlighting the strong need for non-invasive contamination monitoring of whole bat populations.

Biochar obtained from eucalyptus, rice hull, and native bamboo as an alternative to decrease mobility of hexazinone, metribuzin, and quinclorac in a tropical soil.

Mobile herbicides have a high potential for groundwater contamination. An alternative to decrease the mobility of herbicides is to apply materials with high sorbent capacity to the soil, such as biochars. The objective of this research was to evaluate the effect of eucalyptus, rice hull, and native bamboo biochar amendments on sorption and desorption of hexazinone, metribuzin, and quinclorac in a tropical soil. The sorption-desorption was evaluated using the batch equilibrium method at five concentrations of hexazinone, metribuzin, and quinclorac. Soil was amended with eucalyptus, rice hull, and native bamboo biochar at a rate of 0 (control-unamended) and 1% (w w-1), corresponding to 0 and 12 t ha-1, respectively. The amount of sorbed herbicides in the unamended soil followed the decreasing order: quinclorac (65.9%) > metribuzin (21.4%) > hexazinone (16.0%). Native bamboo biochar provided the highest sorption compared to rice hull and eucalyptus biochar-amended soils for the three herbicides. The amount of desorbed herbicides in the unamended soil followed the decreasing order: metribuzin (18.35%) > hexazinone (15.9%) > quinclorac (15.1%). Addition of native bamboo biochar provided the lowest desorption among the biochar amendments for the three herbicides. In conclusion, the biochars differently affect the sorption and desorption of hexazinone, metribuzin, and quinclorac mobile herbicides in a tropical soil. The addition of eucalyptus, rice hull, and native bamboo biochars is a good alternative to increase the sorption of hexazinone, metribuzin, and quinclorac, thus, reducing mobility and availability of these herbicides to nontarget organisms in soil.

Polycyclic aromatic hydrocarbons and their halogenated derivatives in soil from Yellow River Delta: Distribution, source apportionment, and risk assessment.

The distribution of polycyclic aromatic hydrocarbons (PAHs) and halogenated PAHs (HPAHs) in surface soils from the petroleum industrial area of the Yellow River Delta (YRD) in China were investigated. The total concentrations of 16 PAHs ranged from 19.6 to 1560 ng/g, while 22 HPAHs ranged from 2.44 to 14.9 ng/g. Moreover, a high degree of spatial distribution heterogeneity was observed for both PAHs and HPAHs, which is likely attributed to the distinct industrial activities in studied area. The combustion of biomass and petroleum were identified as primary sources of soil PAHs and HPAHs in the YRD. Furthermore, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[g,h,i]perylene exhibited high ecological risks (with risk quotients of 1.47, 1.44, and 1.02, respectively) in specific sites within the YRD. Considering the high toxicity of HPAHs and their potential joint environmental effects with PAHs, continuous attention should be directed towards the environmental risks associated with both PAHs and HPAHs.

Establishing effective interpretation criteria in hair analysis to distinguish between passive and active cocaine exposure: Insights from authentic hair samples collected from professional individuals exposed to cocaine.

Interpretation results of hair analysis, particularly for cocaine, can be challenging due to the need to differentiate between active use or passive contamination. Our study aimed to assess the impact of varying degrees of passive cocaine exposure hair analysis results and their interpretation. Hair samples (n = 25) were categorized based on the declared cocaine exposure of volunteers: (a) high, involving handling up to several kilograms of cocaine powder from dismantling illegal distribution sites; (b) medium, where staff dealt with cocaine blocks (up to kilograms); and (c) low, with staff in contact with up to grams of cocaine for laboratory analysis. Hair samples were decontaminated using dichloromethane, water, and methanol. The samples and final wash were analyzed for cocaine, benzoylecgonine, norcocaine, cocaethylene, m-OH-benzoylecgonine, and ecgonine methyl ester using a validated UPLC-MS/MS method. Cocaine hair concentrations ranges were as follows (pg/mg): high (n = 53 segments) < LLOQ(32)-7046; medium (n = 91) < LLOQ-939; and low (n = 54) < LLOQ-292. All hair samples had concentrations below the LLOQ for cocaethylene, ecgonine methyl ester, and m-OH-benzoylecgonine. Applying the SoHT cocaine cut-off in combination with a hair/wash ratio criterion identified 97% of the samples as contaminated. This study advocates for a comprehensive approach in evaluating cocaine hair concentrations. This involves integrating the 500 pg/mg decision limit for cocaine with a criterion comparing wash and hair concentration. Additionally, confirming the presence of specific metabolites is crucial. This multifaceted method effectively distinguishes between environmental contamination and active cocaine usage. The research contributes significantly to refining cocaine exposure assessment in professional contexts.

Antibiotic residues in pasteurised and Raw Cow's milk in Dhaka, Bangladesh.

This study aimed to investigate antibiotic residues such as oxytetracycline, ciprofloxacin, enrofloxacin and levofloxacin, in both pasteurised and raw cow's milk. A method using high-performance liquid chromatography with a UV detector (HPLC-UV) was developed and validated following International Conference on Harmonization (ICH) guidelines for simultaneous detection and quantification of these residues. The technique demonstrated linearity, with r2 values ranging from 0.999 to 1.00 within the 1.3-15.0 µg ml-1 range for each antibiotic. Thirty cow's milk samples, raw and pasteurised, from Dhaka's local markets were analysed, revealing the presence of enrofloxacin and levofloxacin, while oxytetracycline was absent in all samples. Notably, pasteurised milk samples contained enrofloxacin, levofloxacin and oxytetracycline, with groups P6 and P7 exceeding the Maximum Residue Limit for enrofloxacin, levofloxacin and ciprofloxacin (121 µg l-1). This study emphasises antibiotic residues in milk, with a validated method holding promise for routine analysis in industries requiring simultaneous quantitation of multiple antibiotics.

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 ß-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.

Animal Handling Practice Among Rural Households in Northwest Ethiopia Increases the Risk of Childhood Diarrhea and Exposure to Pathogens From Animal Sources.

Background: In Ethiopia, domestic animals and their feces are not properly contained. However, the risk of exposure to zoonotic pathogens is not well documented. This study was conducted to assess animal handling practices and the risk of childhood diarrhea among rural households in northwest Ethiopia. Methods: This study was done among 403 randomly selected households. Information on animal handling was collected using a questionnaire and spot-check observation. The occurrence of childhood diarrhea in 14 days prior to the survey was assessed based on the reports of female head of households. Multivariable binary logistic regression analysis was performed to identify the association between animal handling practices and childhood diarrhea. Results: All the female head of households had contact with animal feces when preparing fuel disks and plastering the house components with animal dung. Domestic animals shared a corral within the living space of the humans in 20% of the households. Animals entered the human living quarters and accessed foods in 32% of the households. Moreover, 24% of the children aged 24 to 59 months had diarrhea in a 2-week period prior to the survey. Childhood diarrhea was associated with domestic animals sharing the same house as humans (AOR: 3.3, 95% CI: 1.3, 8.6), presence of animal excreta in child playing areas (AOR: 2.4, 95% CI: 1.2, 4.6), contact of domestic animals with stored foods (AOR: 3.5, 95% CI: 2.0, 5.9), trapped dirt under fingernails of female heads (AOR: 3.7, 95% CI: 1.9, 7.5), open defecation (AOR: 3.24, 95% CI: 1.8, 5.9), and unprotected sources (AOR: 4.2, 95% CI: 1.1, 15.3). Conclusion: Domestic animals and their excreta are not hygienically contained in the area. Animal handling practices including their excreta and the hygiene behavior of female head of households (eg, handwashing and food handling practices) should be improved to prevent childhood diarrhea.

Using oral bioaccessibility measurements to refine risk assessment of potentially toxic elements in topsoils across an urban area.

Elevated concentrations of As, Cr, Cu, Ni, Pb, V and Zn in topsoils in Belfast, Northern Ireland have been found to exceed assessment criteria in the city and therefore may pose a risk to human health. Most generic assessment criteria (GAC) for potentially toxic elements (PTEs) in soils assume PTEs are 100% bioavailable to humans. Here we use in-vitro oral bioaccessibility testing using the Unified BARGE method (UBM) to measure what proportion of soil contamination dissolves in the digestive tract and therefore is available for absorption by the body. This study considers how PTE bioaccessibility in soils varies spatially across urban areas and refines human health risk assessment for these PTEs using site specific oral bioaccessibility results to present the first regional assessment of risk that incorporates bioaccessibility testing. A total of 103 urban soil samples were selected for UBM testing. Results showed low bioaccessible fraction (BAF) for the PTEs from geogenic sources: Cr (0.45-5.9%), Ni (1.1-46.3%) and V (2.2-23.9%). Higher BAF values were registered for PTEs from anthropogenic sources: As (8.0-86.9%), Cu (3.4-67.8%), Pb (9.1-106.2%) and Zn (2.4-77.5%). Graphs of bioaccessibility adjusted assessment criteria (BAAC) were derived for each urban land use type and PTE. These provide a visual representation of the significance of oral bioaccessibility when deriving BAAC and how this is affected by 1) dominant exposure pathways for each land use and 2) relative harm posed from exposure to PTEs via each pathway, allowing oral bioaccessibility research to be targeted to contaminants and pathways that most significantly impact risk assessment. Pb was the most widespread contaminant with 16.5% of sites exceeding the Pb GAC. Applying BAAC did not significantly change risk evaluation for these samples as many had Pb BAF>50%. In contrast, all samples that exceeded the As GAC were found to no longer exceed a minimal level of risk when oral bioaccessibility was considered. Oral bioaccessibility testing resulted in a 45% reduction in the number of sites identified as posing a potential risk to human health.

Vertical distribution of 241Am in the southern Baltic Sea sediment profiles.

The contamination of the Baltic Sea with radioactive substances occurred due to the global fallout of atmospheric nuclear weapon tests and the Chernobyl disaster. The knowledge of 241Am in the sediments of the Baltic Sea is limited. Thus, this study aimed to determine 241Am in sediment cores collected from the southern Baltic Sea. Time-based distributions were derived from age-depth profiles using the 210Pb dating method and further corroborated by 137Cs profiles. The activities of 241Am were measured by alpha spectrometry after radiochemical purification. The results show divergences in the concentrations of 241Am at the local level, varying from 0.017 ± 0.001 Bq·kg-1 at the Gotland Basin station to 3.19 ± 0.23 Bq·kg-1 in the Gdansk Basin. These findings enhance our understanding of the radioactive contamination levels in the Baltic Sea and serve as a crucial reference dataset for future assessments and management strategies to mitigate the environmental impact of radionuclides in the region.

Prediction of heavy metal lead contamination accident in Three Gorges Reservoir Area.

Water contamination incidents have become a significant ecological and environmental threat, particularly concerning the security of drinking water source areas (DWSAs). This research aimed to address this issue by integrating Geographic Information System (GIS) into bidimensional hydrodynamic water quality mathematical model developed using C + + and FORTRAN programming languages. The focus was on the Heshangshan drinking water source area (HDWSA), and the TECPLOT360 software was utilized for visualizing pollutant migration and dispersion processes. The study specifically considered a hypothetical lead (Pb) contamination accident, which is situated in the Three Gorges Reservoir Area (TGRA). The spatio-temporal variations in Pb concentration throughout the entire DWSA were analyzed, along with a comparison of Pb concentration changes during different water seasons. The results indicate that, during the accident, the Pb concentration at the water intake in the drought season, decline season, flood season, and impounding season reached the standard limits at 76, 58, 44, and 48 min, respectively. Moreover, the entire DWSA achieved standard levels of Pb concentration at 124, 89, 71, and 74 min during the respective seasons. The study also observed an expansion and subsequent contraction of the Pb contamination area in the DWSA, with the transfer rate of Pb concentration ranked as flood season > impounding season > decline season > drought season.

Element contamination of the Orange-Vaal River basin, South Africa: a One Health approach.

Numerous low-income groups and rural communities depend on fish as an inexpensive protein source worldwide, especially in developing countries. These communities are constantly exposed to various pollutants when they frequently consume polluted fish. The largest river basin in South Africa is the Orange-Vaal River basin, and several anthropogenic impacts, especially gold mining activities and industrial and urban effluents, affect this basin. The Department of Environment, Forestry and Fisheries in South Africa has approved the much-anticipated National Freshwater (Inland) Wild Capture Fisheries Policy in 2021. The aims of this study were (1) to analyze element concentrations in the widely distributed Clarias gariepinus from six sites from the Orange-Vaal River basin and (2) to determine the carcinogenic and non-carcinogenic human health risks associated with fish consumption. The bioaccumulation of eight potentially toxic elements (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn) was assessed in C. gariepinus from sites with different anthropogenic sources. The human health risks were determined to assess the potential risks posed by consuming contaminated C. gariepinus from these sites. Carcinogenic health risks were associated with fish consumption, where it ranged between 21 and 75 out of 10,000 people having the probability to develop cancer from As exposure. The cancer risk between the sites ranged between 1 and 7 out of 10,000 people to developing cancer from Cr exposure. A high probability of adverse non-carcinogenic health risks is expected if the hazard quotient (HQ) is higher than one. The HQ in C. gariepinus from the six sites ranged between 1.5 and 5.6 for As, while for Hg, it was between 1.8 and 5.1. These results highlight the need for monitoring programs of toxic pollutants in major river systems and impoundments in South Africa, especially with the new fisheries policy, as there are possible human health risks associated with the consumption of contaminated fish.

The virome of the kitome: small circular virus-like genomes in laboratory reagents.

In the course of studying the virome of protozoan parasites, we identified small circular genomes resembling viruses, which turned out to be contaminants from an RNA purification kit. We report their sequences here so others can detect possible contamination in their samples by aligning them to these targets.

Influence of a nanoscale coating on plucking fingers and stainless steel on attachment and detachment of Salmonella Enteritidis, Escherichia coli and Campylobacter jejuni.

Gastroenteritis caused by Campylobacter represents the most common reported foodborne bacterial illness worldwide, followed by salmonellosis. Both diseases are often caused by the consumption of contaminated, insufficiently heated poultry meat. This can result from contamination of the meat during the slaughtering processes. Food contact surfaces like stainless steel or plucking fingers contribute significantly to cross-contamination of poultry carcasses. Modification of these surfaces could lead to a reduction of the bacterial burden, as already proven by successful application in various food industry sectors, such as packaging.In this study, nanoscale silica-coated and uncoated stainless-steel surfaces and plucking fingers were compared on a pilot scale regarding attachment and detachment of Campylobacter jejuni, Salmonella Enteritidis and Escherichia coli.The bacteria did not adhere less to the coated plucking fingers or stainless-steel sections than to the uncoated ones. The coating also did not lead to a significant difference in detachment of Campylobacter jejuni, Salmonella Enteritidis and Escherichia coli from the investigated surfaces compared to the uncoated ones.Our study did not reveal any differences between the coated and uncoated surfaces with regard to the investigated bacteria. In order to achieve a better adaptation of the coating to slaughterhouse conditions, future studies should focus on its further development based on the investigation of specific coating parameters.

A realistic combined exposure scenario: effect of microplastics and atrazine on Piaractus mesopotamicus.

Microplastics, considered emerging environmental contaminants resulting from plastic degradation, are discovered in diverse aquatic ecosystems and can be unintentionally ingested by fish. Therefore, it is essential to characterize their interaction with other contaminants, such as agrochemicals, in aquatic environments. This study aimed to assess histological, enzymatic, and genotoxic biomarkers in juvenile pacú (Piaractus mesopotamicus) exposed to polyethylene (PE) microplastic particles and the herbicide atrazine, individually or combined, for 15 days. Four treatments were used: a negative control (CON), PE in the fish diet (0.1% w/w, FPE), atrazine through water (100 µg L-1, ATZ), and the mixture (ATZ+FPE). Results confirmed histological alterations in gills (edema and lamellar fusion) and liver (necrotic areas and congestion) of fish exposed to ATZ and ATZ+FPE. The number of goblet cells increased in the posterior intestine of fish under ATZ+FPE compared to CON and FPE. Enzyme activities (CAT, GST, AChE, and BChE) significantly increased in ATZ+FPE compared to CON. However, no genotoxic effect was demonstrated. These findings provide insights into the complex impacts of simultaneous exposure to atrazine and microplastics, emphasizing the need for continued research to guide effective environmental management strategies against these contaminants that represent a risk to aquatic organisms.

A comprehensive study of colisepticaemia progression in layer chickens applying novel tools elucidates pathogenesis and transmission of Escherichia coli into eggs.

Colisepticaemia caused by avian pathogenic Escherichia coli (APEC) is a challenging disease due to its high economic importance in poultry, dubious pathogenesis and potential link with zoonosis and food safety. The existing in vitro studies can't define hallmark traits of APEC isolates, suggesting a paradigm shift towards host response to understand pathogenesis. This study investigated the comprehensive pathological and microbial progression of colisepticaemia, and transmission of E. coli into eggs using novel tools. In total 48 hens were allocated into three groups and were inoculated intratracheally with ilux2-E. coli PA14/17480/5-/ovary (bioluminescent strain), E. coli PA14/17480/5-/ovary or phosphate buffered saline. Infection with both strains led to typical clinical signs and lesions of colibacillosis as in field outbreaks. Based on lung histopathology, colisepticaemia progression was divided into four disease stages as: stage I (1-3 days post infection (dpi)), stage II (6 dpi), stage III (9 dpi) and stage IV (16 dpi) that were histologically characterized by predominance of heterophils, mixed cells, pyogranuloma, and convalescence, respectively. As disease progressed, bacterial colonization in host organs also decreased, revealed by the quantification of bacterial bioluminescence, bacteriology, and quantitative immunohistochemistry. Furthermore, immunofluorescence, immunohistochemistry, and bacteria re-isolation showed that E. coli colonized the reproductive tract of infected hens and reached to egg yolk and albumen. In conclusion, the study provides novel insights into the pathogenesis of colisepticemia by characterizing microbial and pathological changes at different disease stages, and of the bacteria transmission to table eggs, which have serious consequences on poultry health and food safety.

Growth and Distribution of Bacteria in Contaminated Whole Blood and Derived Blood Components.

Introduction: Bacterial contamination of blood products presumably occurs mainly during blood collection, starting from low initial concentrations of 10-100 colony-forming units (CFUs) per bag. As little is known about bacterial growth behavior and distribution in stored whole blood (WB) and WB-derived blood products, this study aims to provide data on this subject. Methods: WB units were inoculated with transfusion-relevant bacterial species (Acinetobacter baumannii, Bacillus cereus, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Pseudomonas fluorescens, Serratia marcescens, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus dysgalactiae, Streptococcus pyogenes, Yersinia enterocolitica; n = 12 for each species), stored for 22-24 h at room temperature, and then centrifuged for separation into plasma, red blood cells (RBCs), and buffy coats (BCs). The latter were pooled with 3 random donor BCs and one unit of PAS-E each to yield plasma-reduced platelet concentrates (PCs). Samples for bacterial colony counting were collected after WB storage and immediately after blood component production. Sterility testing in PCs (n = 12 for each species) was performed by bacterial culture after 7 days of storage. Results: Bacterial growth in WB varied remarkably between donations and species. Streptococcus species produced the highest titers in WB, whereas Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas fluorescens did not multiply. Centrifugation resulted in preferential accumulation of bacteria in BCs, with titers of up to 3.5 × 103 CFU/mL in BCs and up to ≤0.9 × 103 CFU/mL in BC-derived PCs. Overall, 72/144 PCs (50%) tested positive for bacteria after storage. Sterility test results were species-dependent, ranging from 12 of 12 PCs tested positive for Streptococcus pyogenes to 1 of 12 PCs positive for Escherichia coli. Bacterial contamination of RBC and plasma units was much less common and was associated with higher initial bacterial counts in the parent WB units. Conclusions: Bacterial growth in WB is species-dependent and varies greatly between donations. Preferential accumulation of bacteria in BCs during manufacturing is a critical determinant of the contamination risk of BC-derived pooled PCs.

Does it matter who performs blood culture collection? Results of a survey assessing phlebotomist, nurse, and resident knowledge of blood culture collection protocols.

Blood cultures are the primary method for diagnosing bloodstream infections. However, blood culture contamination (BCC) can lead to unnecessary antibiotic treatment, additional tests, and extended patient time in the hospital. The aim of this quality improvement project was to evaluate healthcare workers' knowledge of blood culture collection protocols and evaluate the blood culture contamination rates of laboratory and non-laboratory staff. We performed a retrospective review of contaminated cultures between May 2021 and April 2022, and anonymous surveys were distributed to assess staff knowledge of proper blood culture collection protocols. Laboratory staff (phlebotomy) had an overall BCC rate of 4.6% compared to a non-laboratory staff (nurses, residents, and medical students) rate of 9.7% (p < 0.0001). On the survey, phlebotomists had the best score (89% correct), followed by nurses (76%) and residents and medical students (64%). These data suggest that blood culture protocol knowledge and BCC rates may be related, with phlebotomists scoring highest on the knowledge survey and demonstrating the lowest contamination rates.

Water contamination: A culprit of serum heavy metals concentration, oxidative stress and health risk among residents of a Nigerian crude oil-producing community.

Niger Delta has become popular for crude oil extraction for the past few decades. This uncoordinated activity has made it a hotspot for xenobiotics exposure and water bodies remain the environmental matrix significantly affected. One of the most deleterious components of crude oil is heavy metals (HMs). This study investigates HMs concentration in water and serum of humans residing in an oil-host community with the consideration of systemic effects, pollution status, carcinogenic and non-carcinogenic health risks and comparison made with residents from a non-oil-producing community. Heavy metal analysis, serum electrolytes, Urea, Creatinine, and liver enzymes were assessed using standard procedures; malondialdehyde, catalase, SOD, glutathione reductase, GPx and total antioxidant capacity (TAC) by spectrophotometry and TNF-α and 8-OHdG assessed via ELISA method. We found altered serum electrolytes; increased serum Pb and Cd levels; increased AST, ALT, ALP and lipid peroxidation; and decreased enzymes antioxidants including TAC among Ugbegugun community residents compared with control. We observed an association between environmental crude oil contamination, ecological and health risks in the community. We concluded that protracted exposure to HMs induces multi-systemic toxicities characterized by DNA damage, depletion of the antioxidant system, and increased free radical generation culminating lipo-peroxidation with significant ecological, carcinogenic, and non-carcinogenic risks characterize crude oil water contamination.