Low-level Contamination Research Articles

Dataset on heavy metal pollution assessment in freshwater ecosystems

Water quality degradation due to heavy metal contamination poses serious threats to both human health and aquatic ecosystems. The rise in the concentration of heavy metals in aquatic environments is largely attributable to anthropogenic activities. These metals accumulate over time in water bodies, necessitating rigorous monitoring to accurately assess pollution levels. The present study is concerned with the assessment of heavy metal pollution in the Styr River (Ukraine) before and after the discharge of water from a nuclear power plant. The assessment is based on three indices: the Heavy Metal Pollution Index, the Heavy Metal Evaluation Index, and the Degree of Contamination. Therefore, heavy metals, including zinc (Zn), cadmium (Cd), lead (Pb), copper (Cu), nickel (Ni), manganese (Mn), arsenic (As) and chromium (Cr), were analyzed in this study. Water samples were collected at two locations on a monthly basis over the course of five years (2018–2022) and subsequently analysed using inductively coupled plasma optical emission spectroscopy. The results indicates a low contamination level at both sampling sites, indicating stable and uniform concentrations of metals across the study area. Moreover, statistical analysis highlights significant associations between certain metals and pollution indices, supporting the indices’ utility in tracking pollution trends and assessing environmental impacts. This dataset underscores the importance of ongoing monitoring for effective water quality management.

Evaluation of Health Risk and Heavy Metal Pollution Caused by Dust Storms in Zabol City.

This study investigated the concentrations and compositions of specific elements in total suspended particulate (TSP) samples and the associated ecological, carcinogenic, and non-carcinogenic risks related to the inhalation, ingestion, and dermal absorption of heavy metals. The study focused on adult and pediatric populations in the highly dust-polluted city of Zabol, Iran, during 2022-2023. The samples were analyzed by using inductively coupled plasma optical emission spectrometry (ICP-OES). The concentration of metals in milligram per kilogram (mg/kg) was as follows: Al (75053) > Ca (8206) > Fe (5439) > Mg (5323) > Zn (15.27) > Pb (3.66) > Cr (3.38) > Cd (0.011); according to the results, the highest amount of metals related to aluminum and calcium in dust particles. The calculated individual indices, including the ecological risk index (ERI), pollution factor (Cfi), and geographic accumulation index (Igeo), indicated that calcium exhibited minimal pollution, while the metal samples (Al, Mg, Fe, Cd, Cr, Pb, and Zn) were categorized as uncontaminated. The results revealed that the ecological risk factor (Er) is below 40, indicating a low level of contamination. Additionally, the pollution level determined by the ecological risk potential (RI) was less than 150, suggesting a low probability of contamination. Ingestion posed the highest average hazard quotient (HQ) values for both children and adults in terms of non-carcinogenic risk assessment, while cutaneous and inhalation exposures showed lower values. Furthermore, the hazard index (HI) for heavy metals remained below the safe threshold of 1. The risk index (RI) values for lead, cadmium, and chromium were all below 1 × 10-6 in both adult and pediatric populations. The United States Environmental Protection Agency (USEPA) guidelines suggest an acceptable level of carcinogenicity for all heavy metals, indicating a potential risk of cancer associated with the presence of these metals in suspended particles in Zabol.

Low pharmaceutical pollution of epibenthic organisms from Admiralty Bay, Antarctica (King George Island, South Shetland Islands)

The presence of medicinal products has been reported in the Antarctic marine environment but still little is known about the bioaccumulation of these compounds. This study was set up to detect and quantify pharmaceutical residues in benthic biota from Admiralty Bay, King George Island (South Shetland Islands, Antarctica). Pharmaceuticals and stimulants were analysed using LC-MS/MS in dominant epibenthic macroorganisms that were collected at eight nearshore sublittoral sites (water depth 3–30 m) by a SCUBA diving team during austral summer (February 2023). Out of 22 analytes, only the stimulant caffeine (CAF) and the antiepileptic carbamazepine (CBZ) have been identified in the macrobenthic algae and invertebrates indicating a relatively low contamination level of the bay. The analytes were detected predominantly in the northern part of the bay (Mackellar Inlet and Martel Inlet) which reflects likely their elevated environmental concentrations in this area and suggests that local research stations represent the main source of pharmaceutical contamination. Irrespective of the sampling site, both compounds were found almost exclusively in brown and red macroalgae highlighting their potential for uptake and accumulation of CAF and CBZ. This study provided the first evidence of the presence of medicinal substances in the Antarctic macrobenthic organisms and can serve as a baseline for environmental risk assessment.

Wash-In Silver Nanoparticle Laundry Additive Was Not Effective in Reducing Bacterial Load on Wrestling Apparel.

The best practice for cleaning wrestling mats is using a residual disinfectant with continued antibacterial action. Recently available wash-in silver additives claim to confer a residual effect to fabric. To test the efficacy of laundering with a wash-in silver additive in reducing athletes' exposure to potentially infectious microbes on apparel. A 4-part controlled laboratory study/parallel group comparison study. (1) To test whether fabrics in athletic clothing would be affected differently, we applied bacteria to control fabrics washed in detergent alone and test counterparts washed in detergent plus wash-in silver additive. Bacteria were applied to fabrics, extracted, plated, incubated, and counted. (2) To see if wash-in silver affected various bacteria differently, we washed cotton t-shirts with detergent alone or with detergent plus wash-in silver. We applied 4 bacterial species commonly found in the wrestling environment. Bacteria were extracted, plated, incubated, and counted. (3) To see if wash-in silver was effective in reducing bacterial contamination during practice, 32 collegiate wrestlers paired off with one wearing a test silver-treated t-shirt and their partner wearing a control shirt. Wrestler rotations exposed shirts to 2, 4, or 8 wrestlers. Identical swatches of fabric were cut from the t-shirts. Bacteria were extracted, plated, incubated, and counted. (4) We simulated prolonged/repeated bacterial exposure as occurs during tournaments by applying bacteria directly to silver-treated and untreated singlet material repeatedly over time. Test samples were taken at regular intervals to see if bacterial growth was inhibited by the presence of the silver nanoparticles. Bacteria were extracted, plated, incubated, and counted. Laboratory and practice. Collegiate Division III wrestling team. Wash-in silver would be considered effective if a statistically significant reduction in bacterial count was observed at 95% confidence. Wash-in silver reduced bacterial growth at low levels of contamination but did not significantly reduce bacterial growth at levels seen during contact sport competitions. This was true for all bacterial species and all fabrics tested. The environmental and potential health risks in using a wash-in silver nanoparticle laundry additive in the wash cycle for clothing worn by wrestlers outweigh any potential infection control benefits to these athletes. We do not currently recommend adopting wash-in silver treatment as part of the laundering regimen for wrestling programs until further testing of alternate methods of silver impregnation into sports fabrics has been investigated.

Assessment of contamination levels, potential ecological and human health risks due to trace elements pollution in the vicinity of the Lolodorf uranium deposit, Southern Cameroon.

The current study assessed the contamination levels and associated ecological and health risks due to hazardous trace elements in soils from Awanda and Mvengue, located in the vicinity of the Lolodorf uranium deposit in Southern Cameroon. Qualitative and quantitative analyses of the soil samples were performed using energy-dispersive X-ray spectrometry. The results indicated that the mean concentrations of metallic and trace elements in soil samples increased in the following order: U < As < Th < Pb < Cu < Ni < Zn < Cr < Mn < Fe < Al. The average concentrations of U, As, Th, Pb, Cu, Ni, Zn, Cr, Mn, Fe, and Al ranged between 0.9-3, 2.9-3.8, 9.2-15, 13.1-20.3, 11.5-42.5, 31.1-60.7, 42.9-91.6, 94.50-170.9, 100.45-500.57, 4874.8-88340 and 226147.5-324240.0mg/kg, respectively. The contamination levels of trace elements were assessed and the human health risk of chemical elements was determined. The investigated elements' average contamination factors (CF) results showed the highest mean CF recorded for Al followed by Cr, Th, Pb, Zn, Cu, Ni, Fe, U, Mn, and As. Furthermore, the findings showed that 90% of soil samples can be classified as considerably contaminated with Al, 100%, and 60% as moderately contaminated with Cr and Th, respectively. The Geo-accumulation indices of Mn, Cr, Th, U, Ni, Zn, Cu, As, and Pb were lower than 1, suggesting low contamination levels for these elements. The ecological factors and risk indices indicated a low ecological risk in the investigated area. In terms of human health risk, ingestion was identified as the primary pathway for both carcinogenic and non-carcinogenic risks, with children found to be more exposed to both risks than adults. Al, Cr, and Fe were found to be the main contributors to non-carcinogenic health risks, while Cr and Ni were the main contributors to carcinogenic health risks.

Extraction of RNA from the fungus Moniliophthora Perniciosa (Stahel) Aime and Phillips-Mora cultivated in induction medium for characterization of chitininases

Chitin is considered the second most important biopolymer in nature, both for its physiological functions in different organisms and for its high availability in the biosphere. However, its natural accumulation does not occur in the environment, this demonstrates that there are natural mechanisms responsible for its degradation. The chitinolytic enzymes found in living beings are targets of great biotechnological interest because they degrade chitin into useful derivatives for various sectors of the economy. Given this, this study aimed to extract RNA for subsequent molecular characterization of chitinases from the fungus Moniliophthora perniciosa. To this end, the fungus was cultivated in WY medium, remaining in the greenhouse for 10-14 days. After growth, RNA was extracted using the traditional Trizol method and the Direct-zol commercial kit. The resulting samples were analyzed using the spectrophotometric technique and verified by photodocumentation after agarose electrophoresis. It was observed that the culture medium was considered satisfactory for RNA extraction and the ideal growth time was 8-10 days for the strain to present sufficient mycelial mass for extraction. Furthermore, the commercial kit used was more favorable than the traditional Trizol method, the product had a low level of contaminants and electrophoresis demonstrated high RNA quality due to the presence of intact rRNA bands. Therefore, as it was extracted from cultivation in a medium that induces chitinase production, the RNA extraction described becomes the most suitable method for the molecular characterization of chitinase production.

Operator-independent assessment of bread spoilage profiles caused by Bacillaceae reveals a high degree of inter- and intraspecies heterogeneity

Ropy bread spoilage caused by aerobic spore-forming bacteria (ASF) is characterized by discoloration, sticky and stringy crumb degradation, and a fruity odor due to the release of volatile organic compounds (VOCs). Previous studies employing model experiments have demonstrated strain-specific spoilage potential. However, to gain a deeper understanding, it is essential to study rope spoilage within baked bread. This study aimed to objectively evaluate the effect of different ASF strains on bread quality. 82 strains were subjected to a comprehensive evaluation, including proteotypic and genotypic fingerprinting, and 13 were selected for further analysis, where ASF endospore-spiked dough samples were baked and incubated. Physical changes in crumb texture, discoloration, and VOC production were quantified using texture analysis, color measurements, and headspace solid-phase microextraction gas chromatography-mass spectrometry. The high intraspecies diversity was reflected in strain-specific variations in rope spoilage profiles. A significant reduction in crumb firmness and increased discoloration, as well as the development of high levels of relative acetoin, were associated with rope spoilage. While color measurements could not detect early-stage spoilage, changes in crumb texture and VOC development were detectable 24 h after baking. Even low levels of contamination (101 spores/g) could cause potential spoilage detectable by texture analysis, although not visible to the naked eye. This study provides an unbiased framework for future research and may help develop early detection tools for improved bread spoilage management.

Free Chlorine Can Inhibit Lead Solder Corrosion via Electrochemical Reversal.

Galvanic corrosion of lead-tin solder in copper plumbing can be a major contributor to water lead contamination. Here, we report the electrochemical reversal of the copper-solder galvanic couple, in which the normally anodic solder becomes cathodic to copper via a reaction with free chlorine. This reversal occurred after a few months of exposure to continuously circulating water with relatively low pH and low alkalinity, causing dramatically decreased lead release and the formation of a Pb(IV) scale. Chloramine did not similarly inhibit solder corrosion over the 4-9 month test duration, resulting in up to 100 times more lead contamination of the water relative to free chlorine. These findings have major implications for corrosion control and public health and can help explain anomalously low levels of lead contamination in some waters with free chlorine that are normally considered corrosive to solder.

Contamination Assessment of Sediments and Bivalves in Estuaries of the Southern Iberian Peninsula

Human activities directly impact estuaries, where the biota is exposed to sediment contamination. A contamination assessment was carried out in several estuaries in the Southern Iberian Peninsula. Sediment samples were analyzed for the presence of metals/metalloids, and bioaccumulation tests were conducted with clams (Ruditapes philippinarum). Huelva Estuary had the highest contamination levels, while the inner bay of Cádiz and the outer stations of the estuaries from Guadiana, Guadalquivir, Palmones, and Guadarranque were the lesser contaminated. All sampling points (except Huelva) had low contamination levels of As and Cd, but they had high concentrations of Cu. The elements Pb, Cd, Zn, Cu, As, and Hg displayed correlations between the concentrations in sediments and the biota. High bioaccumulation of Zn, Cu, and As was observed in Huelva and Barbate. Important insights into the sediment contamination in Southern Iberian Peninsula estuaries suggest greater management and conservation efforts in these critical ecosystems.

Trace element contamination biomonitoring: A comparative study between the polychaetes Alitta virens and Hediste diversicolor

Trace elements (TEs) remain of significant toxicological concern as many are critical for global decarbonisation. TEs accumulate in sediments so benthic polychaetes (e.g. Hediste diversicolor and Alitta virens) are highly relevant for ecotoxicology. However, ecological/biological differences could influence TE accumulation and biomonitoring suitability. Exploiting multiple sympatric populations (Solent, UK), we measure sediment and tissue concentrations generating EFs (enrichment factors), AEIs (Adverse Effects Indexes) and tissue bioaccumulation factors. We also assess stable isotope compositions to elucidate diet influences. Despite diverse anthropogenic activity in the Solent, the majority of TEs present low levels of sediment contamination at the sites. For Ni, Pb and As, a combination of mean AEIs >1 and some sediment concentrations exceeding SQVs (Sediment Quality Values) indicate a slight toxicological risk. For Cu and Hg, high EFs and AEI scores confirm they are the greatest risk, thus requiring source identification/control. However, only mean As tissue concentrations reflect contaminated sites, therefore, identifying the As-source(s) is also a priority. Sediment and tissue concentration relationships were generally negative and not significant for both species. Although a significant negative relationship for Cd for A. virens requires further investigation, the lack of evidence for TE bioaccumulation from sediment may limit both species' biomonitoring suitability for low-contamination sites. Species differences in tissue concentration were also TE specific: H. diversicolor had significantly higher concentrations for Ag, Cu, Hg, Ni and Zn, whilst the reverse was true for Cd, Fe, Cr and As. Whilst ecological differences and that feeding sources are site and species-specific (as evidenced by C, N and S stable isotopes analysis) cannot be ignored, the diverse tissue concentrations strongly suggest different TE regulation strategies per species. Together these data will be important for ecotoxicologists and regulators to select the ‘best’ polychaete biomonitor and assess TE toxicity under future global decarbonisation trajectories for TE inputs.

Evaluation of methods for detection of Campylobacter in raw milk: A multi-country study

Raw milk is considered a high-risk source of Campylobacter due to faecal contamination from healthy cattle and farm environments, thus linking raw milk consumption to global outbreaks. Detection of Campylobacter in raw milk poses challenges due to low contamination levels and antibacterial properties of the milk. Culture-based protocols for Campylobacter detection in milk vary, mainly with regard to pH adjustment and the choice of enrichment broth.This European collaborative study was organised by the EU Reference Laboratory (EURL) for Campylobacter together with eight EU National Reference Laboratories (NRL) for Campylobacter with the purpose to evaluate methods for culture-based detection of Campylobacter in raw cow's milk. The study was divided into two parts, an interlaboratory part and an intralaboratory part, both organised around the same two protocols. The aim of protocol 1 was to evaluate the impact of pH adjustment and storage of the milk on the culturability of Campylobacter over time. Aliquots of the spiked milk were adjusted either to pH 7.0 or pH 7.6 or left unadjusted. The milk was stored up to 48 h at refrigerated temperature and Campylobacter was quantified according to ISO 10272-2 on day 0, 1 and 2. The aim of protocol 2 was to evaluate which enrichment broth, Bolton broth (BB) or Preston broth (PB), showed highest sensitivity in detection of Campylobacter. The spiked milk was enriched in BB and PB as described in ISO 10272-1:2017 or ISO 10272-1:2017/Amd1.2023. In the interlaboratory part, each milk batch was collected locally by each participating NRL/EURL and inoculated with the same Campylobacter strain. In the follow-up intralaboratory part, the EURL-Campylobacter repeated the tests in protocol 1 and 2 but used different Campylobacter strains and strains subjected to thermal stress prior to inoculation.The results show that pH adjustment of raw milk has a negligible impact on culture-based detection of Campylobacter, regardless of strain and level of environmental stress. The composition of milk and properties of the inoculated strain influence culture-based detection of Campylobacter over storage time, and strains subjected to additional stress prior to inoculation in milk are reduced in culturability much faster than the same strains prepared under normal conditions.Finally, the study showed that PB without Campylobacter growth supplement is less effective than BB in detecting Campylobacter in raw milk.

Ecotoxicological impacts of cadmium on soil microorganisms and earthworms Eisenia foetida: from gene regulation to physiological processes

Cadmium is a hazardous heavy metal that is commonly found in the soil and poses significant risks to soil organisms. The toxic effects of Cd on soil microorganisms and earthworms (Eisenia foetida) have been extensively studied, but most studies focused on high Cd pollution levels. Therefore, this study aims to investigate the different responses of soil organisms to moderate and low levels of Cd contamination. According to the study, the presence of 2.5 mg/kg of Cd had a significant impact on the microbial community’s composition and diversity. The relative abundance of most microbes decreased, while the abundance of Firmicutes and Actinobacteriota showed a considerable increase. The LEFSE analysis revealed that the Bacillus genus of the Firmicutes phylum can serve as a biomarker in soil contaminated with 2.5 mg/kg of Cd. At the same time, the functional analysis of PICRUSt 2 shows that microorganisms found in polluted soil have a noticeable decrease in their ability to metabolize lipids. On the other hand, our findings indicate that Cd has a detrimental effect on the biomass of earthworms and induces oxidative stress in these animals. The activation of superoxide dismutase (SOD) and catalase (CAT) enzymes in earthworms was carried out to mitigate oxidative stress. The study found a strong positive relationship between SOD and both time and Cd pollution. However, CAT exhibited inhibition throughout the later stages of the experiment, particularly when exposed to relatively higher levels of pollution. The analysis of RNA in earthworms revealed that soil Cd pollution at a concentration of 2.5 mg/kg primarily impacts the cellular structure and function of earthworms. This pollution disrupts the integrity of the cytoskeleton structure, hampers DNA replication, and compromises the precision of cell signaling. Simultaneously, when compared to the control group, several metabolic pathways exhibited abnormalities.

FS900284 Survey of the Microbiological Contamination of Cull Ewes and Prime Lamb at Slaughter in England and Wales

The aim of this FSA-funded survey was to determine microbial contamination on sheep carcases in abattoirs in England and Wales as the last survey of healthy sheep at slaughter in England and Wales was undertaken 20 years ago. This project was run in conjunction with surveys funded by Defra and the PATH-SAFE research programme aimed at determining prevalence of caecal carriage of pathogens and levels of antimicrobial resistance in sheep at slaughter. Twelve out of 132 abattoirs in England and Wales were recruited, covering 28% of the annual national sheep slaughterhouse throughput. In total,1282 carcase swab samples were collected over a 12-month period from February 2023 to January 2024. All samples were tested for the isolation and quantification of Salmonella, 366 were tested for Campylobacter and 103 were tested for Enterobacteriaceae and E. coli. Salmonella was only detected in 7 (0.55%) of carcase swabs. Five isolates were confirmed as S. enterica subsp. diarizonae serotype 61:k:1:5, a sheep-adapted type with no confirmed association with human disease. The other two isolates were confirmed as S. Typhimurium. Campylobacter contamination was detected on 76 (20.8%) of carcases tested. Prevalence of E. coli (88.4%) and Enterobacteriaceae (75%) was as expected in freshly slaughtered meat, with 81.6% and 84.5% of these samples, respectively, presenting low levels of contamination The contamination detected on sheep carcases was significantly lower than that found in caecal samples examined in the Defra study suggesting that slaughtering processes are effective in reducing carcases being contaminated with pathogens. Correct cooking and hygienic handling and preparation of sheep meat will reduce/eliminate surface microbiological contamination further and reduce the risk to consumers. These results provide valuable baseline data that will help inform risk assessments and risk modelling and will inform future decisions by Government and the meat industry.

Mobile Phase Contaminants Affect Neutral Lipid Analysis in LC-MS-Based Lipidomics Studies.

Lipidomics is a well-established field, enabled by modern liquid chromatography mass spectrometry (LC-MS) technology, rapidly generating large amounts of data. Lipid extracts derived from biological samples are complex, and most spectral features in LC-MS lipidomics data sets remain unidentified. In-depth analyses of commercial triacylglycerol, diacylglycerol, and cholesterol ester standards revealed the expected ammoniated and sodiated ions as well as five additional unidentified higher mass peaks with relatively high intensities. The identities and origin of these unknown peaks were investigated by modifying the chromatographic mobile-phase components and LC-MS source parameters. Tandem MS (MS/MS) of each unknown adduct peak yielded no lipid structural information, producing only an intense ion of the adducted species. The unknown adducts were identified as low-mass contaminants originating from methanol and isopropanol in the mobile phase. Each contaminant was determined to be an alkylated amine species using their monoisotopic masses to calculate molecular formulas. Analysis of bovine liver extract identified 33 neutral lipids with an additional 73 alkyl amine adducts. Analysis of LC-MS-grade methanol and isopropanol from different vendors revealed substantial alkylated amine contamination in one out of three different brands that were tested. Substituting solvents for ones with lower levels of alkyl amine contamination increased lipid annotations by 36.5% or 27.4%, depending on the vendor, and resulted in >2.5-fold increases in peak area for neutral lipid species without affecting polar lipid analysis. These findings demonstrate the importance of solvent selection and disclosure for lipidomics protocols and highlight some of the major challenges when comparing data between experiments.

Arsenic in Rice and Rice-Based Products with Regard to Consumer Health.

Most articles on the exposure to arsenic (As) associated with rice and rice products come from Asia where these products are consumed in the largest quantities; relatively few of the articles have focused on European consumers. Since rice products can represent a significant contribution to overall arsenic exposure, the aim of the study was to determine the total arsenic content (tAs) in rice and the most commonly-consumed rice products available on the Polish market. The tAs determination was performed by hydride generation coupled to inductively-coupled plasma optical emission spectrometry (HG-ICP-OES). Because an inorganic form of As (iAs) is mutagenic and carcinogenic and about 100-fold more toxic than the organic form, an additional aim of the study was to assess the risk of its ingestion, assuming that it constitutes 67.7%, 72.7%, or 90% of tAs. In all products tested, the calculated iAs content was below the maximum permissible levels, and no threat was found for any of the analyzed Polish consumers, based on the mean rice consumption in Poland and the mean calculated iAs content. However, a potential health risk was noted among infants and young children, assuming maximum iAs levels and threefold higher consumption (16.2 g d-1). To avoid a risk of developing cancer, infants up to one year of age should consume no more than 32.2 g of the studied products per week, children under three years of age up to 68.7 g, and adults 243 g. Consumers should strive to include a variety of cereals in their daily diet and choose products shown to have low arsenic contamination levels based on testing and inspection rankings.

Evaluation of the Efficacy of Disinfectants in Reducing Contamination of Bacterial and Viral Murine Pathogens on Gloved Hands

Disinfectant application to gloved hands before handling SPF mice is standard practice to minimize transmission of pathogens and microbial contamination between cages. The risk of contamination with murine pathogens on gloves as well as the efficacy of disinfectant application for this step is largely unknown. This study aimed to determine if murine norovirus (MNV), Helicobacter spp., and Rodentibacter spp. are detectable on gloved hands and, if they are, to evaluate how effective the application of a hydrogen peroxide-based disinfectant (Rescue) or 70% ethanol is in reducing the transfer of these pathogens while handling multiple cages of mice. Mice with natural infections of these pathogens were handled without the application of any disinfectant and the gloves were swabbed for PCR testing. All pathogens were detected via PCR with Helicobacter spp. the most frequently transferred in 83% of the cages handled. The mice were then divided into 4 treatment groups based on the product applied to gloves before handling: Rescue, 70% ethanol, sterile water, and no product. Mice in each cage were briefly handled, and the gloves were swabbed with ATP swabs after each cage and swabs for PCR testing after handling 4 and 9 cages, consecutively. All pathogens were detected via PCR in all treatment groups, and neither Rescue nor 70% ethanol was superior to water or no product in reducing contamination. Rescue and 70% ethanol were effective in maintaining lower levels of organic microbial contamination than water and no product for consecutive handling of up to 3 and 4 cages of mice, respectively. This study indicates that exposure to MNV, Helicobacter spp., and Rodentibacter spp. from handling mice is a risk and the application of Rescue or 70% ethanol is not completely effective in eliminating transfer of these pathogens.

Unveiling the dynamics of intraoperative contamination in total hip arthroplasty: the discrepancy between particulate and microbial contamination in surgical site infection risk

BackgroundSurgical site infection (SSI) is a major problem following total hip arthroplasty (THA). This study investigated the impact of a standard intraoperative routine where the surgical team wears full-body exhaust suits (space suits) within a laminar airflow (LAF)-ventilated operating room (OR) on environmental contamination. Our primary objective was to identify potential modifiable intraoperative factors that could be better controlled to minimize SSI risk.MethodsWe implemented an approach involving simultaneous and continuous air sampling throughout actual primary cementless THA procedures. This method concurrently monitored both airborne particle and microbial contamination levels from the time the patient entered the OR for surgery until extubation.ResultsAirborne particulate and microbial contamination significantly increased during the first and second patient repositionings (postural changes) when the surgical team was not wearing space suits. However, their concentration exhibited inconsistent changes during the core surgical procedures, between incision and suturing, when the surgeons wore space suits. The microbial biosensor detected zero median microbes from draping to suturing. In contrast, the particle counter indicated a significant level of airborne particles during head resection and cup press-fitting, suggesting these procedures might generate more non-viable particles.ConclusionsThis study identified a significant portion of airborne particles during the core surgical procedures as non-viable, suggesting that monitoring solely for particle counts might not suffice to estimate SSI risk. Our findings strongly support the use of space suits for surgeons to minimize intraoperative microbial contamination within LAF-ventilated ORs. Therefore, minimizing unnecessary traffic and movement of unsterile personnel is crucial. Additionally, since our data suggest increased contamination during patient repositioning, effectively controlling contamination during the first postural change plays a key role in maintaining low microbial contamination levels throughout the surgery. The use of sterile gowns during this initial maneuver might further reduce SSIs. Further research is warranted to investigate the impact of sterile attire on SSIs.

Study on reference material of heavy metals (lead, cadmium, arsenicic, and mercury) in mustard greens by natural infection method

Vegetables are an essential part of daily meals. Each type contains different nutrients and serves various functions, but all provide essential nutrients for human health. Many metal elements are known to play important roles in living organisms and humans. However, heavy metal contamination can be toxic to the body and impact the health of consumers. To ensure the quality of vegetable products, determining the levels of heavy metals (Pb, Cd, As, Hg) is crucial for food safety control in vegetables. Therefore, using heavy metal standard samples (Pb, Cd, As, and Hg) in vegetables provides reference values and accuracy benchmarks for testing results, aiding in precise and objective evaluation during sample testing. This study aims to develop a process for creating standard samples for analyzing heavy metals Pb, Cd, As, and Hg in vegetables using a natural contamination method. The produced samples demonstrated consistency and stability, with an estimated duration of 627 days from the production date. The measurement uncertainty ranges from 7,94% to 15,7%. The values of the standard samples align with the low contamination levels required for analysis, making them suitable for quality control in laboratories. Additionally, the results of this study lay the groundwork for further research into developing other standard samples with diverse matrices and analytical criteria using natural contamination methods.

Groundwater Quality and Potential Health Risk Assessment for Potable Use

The Ramganga River basin, comprising three rivers, the Dhela, Dhandi, and Ramganga, plays a vital role in groundwater recharge, sustaining numerous industries, urban areas, and rural communities reliant on these rivers for daily activities. The study’s primary purpose was to analyze the groundwater quality in the context of potability, irrigation, and health risks to the local inhabitants of the Ramganga River basin. In 2021–2022, 52 samples (26 × 2) were collected from 13 locations in two different seasons, i.e., pre-monsoon and post-monsoon, and 20 physico-chemical and heavy metal and metalloids were analyzed using the standard protocols. The result shows that heavy metal and metalloids and metalloid concentrations of Zn (0.309–1.787 and 0.613–1.633); Fe (0.290–0.965 and 0.253–1.720), Cd (0.001–0.002 and 0.001–0.002); As (0.001–0.002 and 0.001–0.002), Cr (0.009–0.027 and 0.011–0.029), and Pb (−0.001–0.010 and 0.00–0.010) values in mg/L are present in both seasons. The groundwater quality index (GWQI), heavy metal pollution Index (HPI), and heavy metal evaluation index (HEI) were used to assess the water quality and metal pollution in the basin area. As per GWQI values, water quality lies from excellent water quality (41.639 and 43.091) to good water quality (56.326 and 53.902); as per HPI values, it shows good (29.51 and 30.03) to poor quality (60.26 and 59.75) and HEI values show the low-level contamination (1.03–2.57 and 1.13–3.37) of heavy metal and metalloids in both seasons. According to the potential health risk assessment, infants show low risk in pre-monsoon and low risk to medium post-monsoon, while children and adults show low risk to high risk in both seasons. From the health risk perspective, it shows that children and adults have more concerns about non-carcinogenic effects, so adequate remedial measures and treatment are required to avoid the groundwater quality of the Ramganga River basin.

Assessing the Effects of Surgical Irrigation Solutions on Human Neutrophil Interactions with Nascent Staphylococcus aureus Biofilms.

Staphylococcus aureus (S. aureus) is the leading cause of surgical site infections (SSIs) and is capable of biofilm growth on implanted foreign devices. The use of surgical irrigation solutions has become a common strategy to combat bacterial contamination events that occur during surgery. Despite their antimicrobial activity, SSI rates remain consistent, suggesting that low-level contamination persists. In these cases, circulating neutrophils must traffic from the blood to contamination sites to aid in bacterial clearance. The influence of irrigation solutions on neutrophils' ability to engage with bacteria has not been explored. The effects of three commonly used irrigation solutions: Xperience (sodium lauryl sulfate), Irrisept (chlorhexidine gluconate), and Betadine® (povidone-iodine) on nascent S. aureus biofilms alone and in the presence of human neutrophils were assessed at manufactured and diluted concentrations. All three solutions, at a 10% dilution, inhibited bacterial growth as demonstrated by culture assays and confocal video microscopy of bacterial aggregate formation. The effects of 10% dilutions of each of these solutions on neutrophil membrane integrity (by flow cytometry and propidium iodide staining) and motility (by confocal video microscopy of neutrophil track length) were investigated with differing outcomes for each irrigation solution. At this concentration only Irrisept preserved neutrophil membrane integrity and motility. Together, this study examines an overlooked aspect of surgical irrigation solutions by investigating their impact on innate immunity and highlights the feasibility of formulations wherein solution effectiveness is complemented by neutrophil function to reduce risks of infection.