Potential Sources Of Contamination Research Articles

Anthropogenic particle abundance and characteristics in seawater and intertidal sediments of the Tonkin Bay Coast (North Vietnam).

Microplastics (MPs, plastic items from 1µm to 5mm in size) are present in all environmental compartments. The evaluation of their concentration, fate, and spatial distribution is still a challenge for the scientific community. This concern is just debuting in developing countries, (i.e., Asia, South America, and Africa). This study deals with the MP contamination in the abiotic marine compartments of Northern Vietnam: seawater and intertidal sediments. Four sites located in the intertidal zone or near the coastline in Tonkin Bay, Vietnam were studied. A total of 16 samples (eight for each compartment) were collected in July 2020 (rainy season) and January 2021 (dry season). Anthropogenic particles (total observed fibers and fragments) were found at levels ranging from 3 to 303 particles/m3 in seawater and from 63 to 955 particles/kg dry weight in sediments. Most of these were fibers less than 300-µm long. Higher levels of seawater at the Nam Dinh site were found in the rainy season compared to the dry one. As the river flow was estimated six times higher during the rainy season than during the dry season, these results suggest the river discharge is a potential source of contamination for the coastal zone. The temporal variability was lower for the sediments than for the seawater, suggesting the long-term integration of the anthropogenic particles in this compartment. A small portion of sorted particles were analyzed by µFTIR (8.35%), and this sub-sample was only composed of fragments. Still, fragments were mostly composed of polypropylene (PP, 82%), polyethylene (PE, 9%), and polystyrene (PS, 9%). The fragment size was similar in the two studied compartments, but it was dependent on polymer types since PS fragments (140 ± 17µm) were smaller than those made of PE (622 ± 123µm) and PP (869 ± 905µm). Future works should investigate the smallest fraction of MP (even nanoplastics) as well as find solutions in order to mitigate MP contamination in the marine environment.

Significance of the apiary location for the content of copper and zinc in the bee pollen

Bee pollen is one of the most valuable direct products of honey bees. Bees as well as humans use pollen in their nutrition as a high-quality supplement. Therefore, information about the mineral content of pollen is valuable. The aim of this study was to determine the amounts of copper (Cu) and zinc (Zn) in the bee pollen collected from the three locations (Kozarska Dubica, Petrovo, and Srbac). Quantification of copper and zinc was done by atomic absorption spectrophotometry after acid digestion (HNO3+HClO4) of pollen. The highest contents of both elements were found in the bee pollen from Kozarska Dubica (8.41 mg Cu/kg, 29.52 mg Zn/kg). The lowest Cu content was found in the samples from Petrovo (6.19 mg/kg), while the lowest Zn content was determined in the pollen from Srbac (22.06 mg/kg). Additionally, there were statistically significant differences in the content of both elements between pollen originating from different locations. As the location of the apiary was mainly determined by its proximity to potential sources of metal contamination, botanical origin of pollen and technology of pollen collection, it is important to investigate their impact in more detail on the elemental content of pollen in the future.

Estimation of potential health risks on metals and metalloids contaminants in black goby (Gobius niger) consumption in selected niger delta coast, nigeria

IntroductionThe Niger Delta in Nigeria is subject to anthropogenic influences, impacting the quality of its water bodies, including the Sombrero River. This study aims to investigate the concentrations of metals and metalloids in Gobius niger from the Sombrero River, as these contaminants can pose risks to human health through seafood consumption. Specifically, zinc (Zn), iron (Fe), copper (Cu), lead (Pb), arsenic (As), and cadmium (Cd) were analyzed using atomic absorption spectroscopy (AAS). Materials and MethodsSamples were collected from three different stations along the Sombrero River. The concentrations of Zn, Fe, Cu, Pb, As, and Cd were determined using AAS. Hazard Quotients (HQ), Chronic Daily Intake (CDI), Hazard Index (HI), and Individual Lifetime Cancer Risk (ILCR) values were calculated to assess the potential health risks associated with consuming fish contaminated with these metals and metalloids. ResultsStation 1 had the highest Zn concentration, followed by Fe, Cu, Pb, Cd, and As, with Zn reaching 104.8 ± 1.37 mg kg−1. Station 2 exhibited a similar trend, while Station 3 had Zn as the predominant metal and metalloid. Notably, Pb, As, and Cd levels were consistently low at all stations. While Pb was within permissible limits set by FAO/WHO for contaminants in the fish samples, Zn exceeded regulatory guidelines, suggesting a potential source of contamination. Hazard Quotients (HQ) highlighted a significant risk associated with zinc, especially for children. Chronic Daily Intake values showed metals in fish consumed by adults and children were generally within safe limits, except for Zn, which exceeded Maximum Tolerable Daily Intake (MTDI). Hazard Index values pointed to a substantial long-term health risk, particularly for children due to high zinc levels. However, Individual Lifetime Cancer Risk (ILCR) values were generally below 1, indicating relatively low cancer risks from G. niger consumption for both age groups. ConclusionThis study emphasizes the need for monitoring and managing metals and metalloid pollution in the Niger Delta region to ensure safe seafood consumption and community well-being. While certain metals pose minimal health risks, it highlights the necessity of specific interventions to reduce excessive zinc exposure and safeguard long-term health in the region.

Listeria monocytogenes Contamination Leads to Survival and Growth During Enoki Mushroom Cultivation

Two recent outbreaks of listeriosis have been linked to the consumption of enoki mushrooms. After the first outbreak, import sampling by the U.S. FDA identified that 43% of the samples evaluated were positive for Listeria monocytogenes (Lm). These observations raised questions about the potential sources of Lm contamination of enoki mushrooms. One potential source of contamination is during enoki mushroom cultivation, as growing conditions are comparatively cool and moist to induce mushroom germination, to which Lm is well adapted. Two varieties of enoki mushrooms were evaluated to determine the potential for Lm to contaminate enoki cultures when introduced at various points during cultivation (inoculation, scraping, pinning, and collaring). The results of two trials showed that Lm established contamination and grew to similar levels in the substrate regardless of when Lm was introduced and, with one exception, did not alter the rate of mushroom generation to below the control. Enumeration of Lm in enoki mushroom cultures at harvest found an average contamination of 103 cfu/g, though the results were variable. Refrigerated storage for six weeks was found to result in an increase in Lm. Additionally, no statistically significant difference in the levels of Lm was observed based on proximity to the substrate, though levels of Lm in the different enoki samples correlated with levels of Lm in the substrate at harvest, but not at scraping. The ability of Lm to grow independently in the media used to culture enoki was assessed, and Lm was found to be unable to grow but could sporadically survive in Masters Mix. No growth of Lm was observed in potato dextrose broth, though growth could occur on the agar. Overall, the data indicate a high potential for the establishment of Lm contamination at any point during enoki cultivation to result in Lm-contaminated mushrooms. These data indicate a need for active control mechanisms to prevent the introduction of Lm to enoki cultures.

Composting manure in the poultry farm harbours multidrug-resistance Salmonella

ABSTRACT Salmonella is one of the leading foodborne pathogens that cause gastroenteritis. It is imperative to monitor Salmonella contamination within poultry farms. This study focuses on the prevalence of Salmonella in composting manure at poultry farms a potential and persistent contamination sources. A batch of manure samples (n = 10) were collected from a local poultry farm, and half of the manure samples were detected to be Salmonella-positive. Serotyping results showed four serotypes among different isolated strains, including Typhimurium, Typhi, Newport, and Dublin. Isolates from manure generally demonstrated a high ciprofloxacin resistance and biofilm formation capacity. Multi-drug resistance was found in isolates from organic manure that had been fermented using high-temperature aerobic technology. Our study indicated that composting manure harboured Salmonella and might facilitate the transmission of Salmonella and the development of antimicrobial resistance. Proper composting strategies are needed to reduce the transmission of antimicrobial resistance and Salmonella.

Detection and Screening of Organic Contaminants in A Riverine System of Georgia Using Non-Targeted Analysis

Numerous organic chemicals exist within aquatic environments, yet effectively screening and prioritizing them is a huge challenge. This study provides a comprehensive investigation into the ecological dynamics of the North Oconee River within Athens-Clarke County, Georgia, with a specific focus on the distribution of 33 identified compounds, including a prominent pesticide. The research, conducted in the riverine ecosystems proximal to the Firefly trail, employs advanced analytical techniques to elucidate potential contamination sources arising from agricultural and urban runoff. Intriguingly, the study reveals North Oconee River near the Firefly Trail as a notable site for heightened pesticide contamination, warranting a meticulous exploration of its origins. Furthermore, the investigation unveils the intricate microbial degradation processes of malathion within the North Oconee River, elucidating the pivotal role played by microbial activity in river water. The detection of degradant byproducts prompts the considerations of bioavailability and toxicity, associating potential implications for the river’s overall ecological health. Ongoing research endeavors to precisely quantify environmental risks and unravel indigenous microbial degradation pathways, presenting pivotal contributions to the scientific community’s understanding of complex riverine ecosystems. This research serves as a foundational piece in informing sustainable environmental management practices and emphasizes the urgency of comprehensive stewardship in safeguarding aquatic ecosystems.

Resource utilization of gasified fine ash from entrained flow bed via thermal modification-melting combustion: A pilot study

China generates substantial quantities of gasified fine ash (GFA) annually through entrained flow bed coal gasification processes. These GFAs are laden with significant amounts of poorly reactive carbon and abundant ash resources, including silica, aluminum. Typically GFA represent not only a gross squandering of resources but also a potential source of environmental contamination. In order to use both ash and carbon of GFA, our team has developed the thermal modification -melting combustion method. The study conducted thermal modification-melting combustion experiments of GFA with auxiliary heating fuel and varying moisture content on a pilot-scale experimental platform. The aim was to ascertain the influence of operating conditions on the physical and chemical properties of GFA fuel, as well as the carbon conversion rate of GFA and the potential for reusing ash after melting combustion in the entire system. The results indicate that an increase in the moisture content of GFA allows the thermally modified fine ash (MFA) to possess smaller particle sizes and more reactive sites in carbon structures, along with higher combustible gas yield and calorific value. Post-melting combustion, the residual carbon conversion rate in GFA surpassed 96.88 %, indicative of a high recovery potential. Moreover, the ash slag, rich in inorganic non-metallic glassy phases, emerged as a promising candidate for material reuse and application.

Is paper bag plastic-free, without plastic in colourful logo area?

The concern over plastic contamination has led to bans on plastic shopping bags, often replaced by paper ones. However, logos painted or printed on paper bags may still contain plastics, as investigated herein. In some logos, for example, white pigment of titanium dioxide (TiO2) nanoparticles are bound with plastic binder onto the cellulose surface of the paper. This hybrid of plastic and nanoparticle is examined using scanning electron microscope (SEM) to characterise morphology physically, and Raman imaging to identify and visualise them chemically. Raman imaging scans the sample to separate images and identify not only plastic but also the co-formulated pigment. The scan generates a hyperspectral matrix containing hundreds to thousands of spectra, and subsequent analysis can enhance the signal-to-noise ratio. Decoding the hyperspectral matrix using chemometrics like principal component analysis (PCA) can effectively map plastic and pigment separately with increased certainty. The image can be further refined through 3-dimensional surface fitting for deconvolution, providing direct visualisation of the plastic-nanoparticle hybrid at a density of approximately 7.3 million particles per square millimetre. Overall, caution should be exercised when using paper bags, as they may not be entirely free of plastics. Raman imaging proves to be an effective method for identifying and visualising complex components, including plastics and nanoparticles. Environmental ImplicationThe concern over plastic contamination has led to bans on plastic shopping bags, replaced by paper alternatives. However, some logos on paper bags may still contain plastics, which is investigated to confirm the presence of plastic-nanoparticle hybrid using SEM and Raman imaging. By employing decoding algorithms such as PCA to separately map plastic and pigment, and utilising 3D surface fitting to deconvolute the image, the hybrid plastic-nanoparticle is estimated at a density of approximately 7.3 million particles per square millimetre. It's important to exercise caution and not assume these items are plastic-free. This aspect of plastics may have been overlooked as another potential source of contamination.

Emerging organophosphite and organophosphate esters in takeaway food and the implications for human exposure.

Takeaway food has become a prominent component of the diet in urban areas of China, especially for young people. Although dietary intake is a major pathway to contaminants for human exposure, studies on emerging organophosphite antioxidants (OPAs) and organophosphate esters (OPEs) in food are scarce. Here, we investigated four OPAs and 19 OPEs in takeaway foods (n = 99) and paired takeaway food packaging (n = 50) in China. AO168=O (mean: 14.9 ng/g ww), TPPO (mean: 1.05 ng/g ww), and TCIPP (mean: 0.579 ng/g ww) were dominant in the takeaway food. Some OPEs had significant correlations in takeaway food. Emerging OPAs and OPEs in takeaway food varied significantly depending on the packaging materials and food types. AO168 and AO168=O were widespread in the paired takeaway food packaging. The migration efficiencies of emerging OPAs and OPEs were low in takeaway food packaged in aluminum foil. Although the actual contamination of emerging OPAs and OPEs in takeaway food significantly differed from those of in food simulants migrated from paired takeaway food packaging, the results imply that food itself and takeaway food packaging are potential contamination sources of emerging OPAs and OPEs in takeaway food. The average estimated dietary intakes of emerging OPAs and OPEs were 465 ng/kg body weight (bw)/day and 91.9 ng/kg bw/day, respectively. The exposure risk of emerging OPAs and OPEs through takeaway food intake is low in China.

Dissemination of antibiotic resistance genes from aboveground sources to groundwater in livestock farms

Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are prevalent in various environments on livestock farms, including livestock waste, soil, and groundwater. Contamination of groundwater by ARB and ARGs in livestock farms is a growing concern as it may have potentially huge risks to human health. However, the source of groundwater-borne ARB and ARGs in animal farms remains largely unknown. In this study, different types of samples including groundwater and its potential contamination sources from aboveground (pig feces, wastewater, and soil) from both working and abandoned swine feedlots in southern China were collected and subjected to metagenomic sequencing and ARB isolation. The source tracking based on metagenomic analysis revealed that 56–95 % of ARGs in groundwater was attributable to aboveground sources. Using metagenomic assembly, we found that 45 ARGs predominantly conferring resistance to aminoglycosides, sulfonamides, and tetracyclines could be transferred from the aboveground sources to groundwater, mostly through plasmid-mediated horizontal gene transfer. Furthermore, the full-length nucleotide sequences of sul1, tetA, and TEM-1 detected in ARB isolates exhibited the close evolutionary relationships between aboveground sources and groundwater. Some isolated strains of antibiotic-resistant Pseudomonas spp. from aboveground sources and groundwater had the high similarity (average nucleotide identity > 99 %). Notably, the groundwater-borne ARGs were identified as mainly carried by bacterial pathogens, potentially posing risks to human and animal health. Overall, this study underscores the dissemination of ARGs from aboveground sources to groundwater in animal farms and associated risks.

Identifying Potential Sources of Phthalate Contamination in the Leaves of Stevia Rebaudiana (Bertoni) and the Development of Removal Technology.

Steviosides extracted from the leaves of the plant Stevia rebaudiana are increasingly used in the food industry as natural low-calorie sweeteners. Phthalates in food are often assumed to arise from food containers or packaging materials. Here, experiments were carried out to identify the potential sources of DMP, DBP, DIBP, and DEHP in the leaves of stevioside through investigation of their content in native stevioside tissues, soils, and associated agronomic materials. The results show that phthalate contamination was present in all the samples tested, and the influence of regional factors at the provincial level on the content of plasticizers in stevia leaves was not significant. Phthalates in stevia leaves can be absorbed into the plant body through leaves and roots. Using resin removal, the phthalate content in stevioside glycosides was reduced to less than 0.05 ppm, and some indicators were far lower than the limit standard in EU food.

Legacy and emerging per- and polyfluoroalkyl substances in tissue and toilet paper from China

Per- and polyfluoroalkyl substances (PFASs) have been found in toilet paper in Europe, the United States, and Africa; however, their presence in Chinese household paper has not been investigated. In this study, 21 legacy and 30 emerging PFASs were analyzed in tissue and toilet paper from China, including 48 samples of different origins and materials. Median concentrations of chlorinated polyfluorinated ether sulfonates (Cl-PFESAs), hexafluoropropylene oxide homologs (HFPOs), and p-perfluorous nonenoxybenzenesulfonate (OBS) were 0.32, 0.19, and 0.10 ng/g dry weight (dw), respectively. The detection frequencies (DFs) of Cl-PFESAs and OBS both were greater than 96%, followed by hexafluoropropylene oxide trimer acid (HFPO-TrA, DF: 85%). Notably, the level of HFPO-TrA in one sample was as high as 540 ng/g dw, indicating a potential environmental risk to humans. In addition, the concentrations of Cl-PFESAs in toilet paper were significantly higher than that in tissue (p < 0.05). However, no significant differences were observed in the concentrations of PFASs in tissue and toilet paper from different materials and origins. This suggests that PFASs, particularly emerging PFASs, are widely detected in tissue and toilet paper products across China, and their presence is a potential source of landfill contamination and human exposure.

Occurrence and Health Risk Assessment of Phthalates in Municipal Drinking Water Supply of a Central Indian City.

In this study, the occurrence of phthalates in the municipal water supply of Nagpur City, India, was studied for the first time. The study aimed to provide insights into the extent of phthalate contamination and identify potential sources of contamination in thecity's tap water. We analyzed fifteen phthalates and the total concentration (∑15phthalates) ranged from 0.27 to 76.36µgL-1. Prominent phthalates identified were di-n-butyl phthalate (DBP), di-isobutyl phthalate (DIBP), benzyl butyl phthalate (BBP), di (2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DNOP), and di-nonyl phthalate (DNP). Out of the fifteen phthalates analyzed, DEHP showed the highest concentration in all the samples with the median concentration of 2.27µgL-1, 1.39µgL-1, 1.83µgL-1, 2.02µgL-1, respectively in Butibori, Gandhibaag, Civil Lines, and Kalmeshwar areas of the city. In 30% of the tap water samples, DEHP was found higher than the EPA maximum contaminant level of 6µgL-1. The average daily intake (ADI) of phthalates via consumption of tap water was higher for adults (median: 0.25µgkg-1day-1) compared to children (median: 0.07µgkg-1day-1). The hazard index (HI) calculated for both adults and children was below the threshold level, indicating no significant health risks from chronic toxic risk. However, the maximum carcinogenic risk (CR) for adults (8.44 × 10-3) and children (7.73 × 10-3) was higher than the threshold level. Knowledge of the sources and distribution of phthalate contamination in municipal drinking water is crucial for effective contamination control and management strategies.

Assessment of carcinogenic and non-carcinogenic risk of exposure to potentially toxic elements in tea infusions: Determination by ICP-OES and multivariate statistical data analysis

BackgroundThe perennial evergreen tea (Camellia sinensis) plant is one of the most popular nonalcoholic drinks in the world. Fertilizers and industrial, agricultural, and municipal activities are the usual drivers of soil contamination, contaminating tea plants with potentially toxic elements (PTEs). These elements might potentially accumulate to larger amounts in the leaves of plants after being taken up from the soil. Thus, frequent monitoring of these elements is critically important. MethodsThe present study intended to determine PTEs (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in both tea leaves and infusions using ICP-OES. Various multivariate data analysis methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to elucidate the potential sources of PTEs contamination, whether from anthropogenic activities or natural origins. Additionally, Pearson's correlation coefficient (PCC) was calculated to assess the relationships between the variables under study. ResultsThe mean contents (mg/L) of all studied elements in tea infusions decreased in order Mn (150.59 ± 1.66) > Fe (11.39 ± 0.99) > Zn (6.62 ± 0.89) > Cu (5.86 ± 0.62) > Co (3.25 ± 0.64) > Ni (1.69 ± 0.23) > Pb (1.08 ± 0.16) > Cr (0.57 ± 0.09) > Cd (0.46 ± 0.09) > Al (0.05 ± 0.008), indicating that Mn exhibits the highest abundance. The mean concentration trend in tea leaf samples mirrored that of infusions, albeit with higher concentrations of PTEs in the former. The tolerable dietary intake (TDI) value for Ni and provisional tolerable monthly intake (PTMI) value for Cd surpassed the standards set by the WHO and EFSA. Calculated hazard index (HI < 1) and cumulative cancer risk (CCR) values suggest negligible exposure risk. ConclusionElevated levels of PTEs in commonly consumed tea products concern the public and regulatory agencies.

Adaptive Equipment Utilized in Rehabilitation as a Potential Source of Bacterial Contamination

Adaptive Equipment Utilized in Rehabilitation as a Potential Source of Bacterial Contamination

Impact of medical waste bin on contamination of patient’s environment: an experimental study

BackgroundMedical waste bins are potential source of microbial contamination in hospital environment, while there is no clear guidance for the management of them. We aimed to assess the impact of medical waste bins on patient’s environment. MethodsThis experimental study simulated microbial contamination by performing medical procedures on a patient model with fluorescent lotion. The waste bin was set as initially empty or two-thirds filled with waste, open or with a lid. The percentage of fluorescent contaminated area in designated patient’s environments was analyzed by two independent observers. ResultsAmong a total of 120 experiments, the sides of the bins were more contaminated in open-occupied bins compared to open-empty bins and in open-occupied bins compared to lid-occupied bins (median 1.9175% vs. 0.0916% [P=0.001] and 1.9175% vs. 0.0899% [P=0.003], respectively). The top of bedside equipment trolley for preparing medical procedure was more contaminated in lid-occupied bins than open-occupied bins (median 0.0080% vs. 0.0040%, P=0.013). DiscussionIn addition to reducing contamination of bin itself, the manually operated lid had potential risk of contributing microbial transmission by contaminating equipment trolley. ConclusionsMedical waste bin should be kept no more than two-thirds full, and cautions should be taken when using manually operated lid, to avoid cross-contamination.

Detecting contamination events during robotic total joint arthroplasty

Robot-assisted total joint arthroplasty (robotic-TJA) has become more widespread over the last 20 years due to higher patient satisfaction and reduced complications. However, robotic TJA may have longer operative times and increased operating room traffic, which are known risk factors for contamination events. Contamination of surgical instruments may be contact- or airborne-related with documented scalpel blade contamination rates up to 9%. The robot arm is a novel instrument that comes in and out of the surgical field, so our objective was to assess whether the robot arm is a source of contamination when used in robotic TJA compared to other surgical instruments. This was a prospective, single-institution, single-surgeon pilot study involving 103 robotic TJAs. The robot arm was swabbed prior to incision and after closure. Pre- and postoperative control swabs were also collected from the suction tip and scalpel blade. Swabs were incubated for 24hours on tryptic soy agar followed by inspection for growth of any contaminating bacteria. A contamination event was detected in 10 cases (10%). The scalpel blade was the most common site of contamination (8%) followed by the robot arm (2%) and suction tip (0%). Robotic TJA is contaminated with bacteria at a rate around 10%. Although the robot arm is an additional source of potential contamination, the robot arm accrues bacterial contamination infrequently compared to the scalpel blade. Contamination of the robot arm during robotic TJA is minimal when compared to contamination of the scalpel blade.

Spatiotemporal variations in the occurrence of Campylobacter species in the Bloukrans and Swartkops rivers, Eastern Cape, South Africa

An increase in the incidence of Campylobacter species in rivers raises concerns on the safety of river water for humans who get exposed to river water. This study examines the spatiotemporal dynamics of Campylobacter species in the Bloukrans and Swartkops rivers, analysing patterns of its occurrence in relation to meteorological conditions, physicochemical parameters, seasons, and sampling sites. Physico-chemical parameters and meteorological conditions were measured during water sampling from various sites along the rivers over a year, while Polymerase Chain Reaction (PCR) was utilised to detect Campylobacter genus-specific genes and selected antibiotic-resistant genes. Campylobacter was detected in 66.67% (Bloukrans River) and 58.33% (Swartkops River). In the Bloukrans River, multi-drug resistance genes cmeA (20%), cmeB (65%), cmeC (10%), were detected while and tetO was detected at 70%. In the Swartkops River, the corresponding prevalence were 28%, 66.67%, 28.56%, and 76%. The study indicates that sampling season did not significantly impact Campylobacter prevalence. However, variation in Campylobacter occurrence exists among different sites along the rivers, reflecting the influence of site proximity to potential contamination sources. The study suggests that Campylobacter infection may be endemic in South Africa, with rivers serving as potential sources of exposure to humans, thereby contributing to the epidemiology of campylobacteriosis.

Identification of microbial communities and multi-species biofilms contamination in seafood processing environments with different hygiene conditions

Biofilms formed by spoilage and pathogenic bacteria increase microbial persistence, causing an adverse influence on the quality of seafood. The mono-species biofilms are widely reported, however, the contamination of multi-species biofilms and their matrix in food environments are still not fully understood. Here, we assessed the contamination of multi-species biofilms in three seafood processing environments with different hygiene levels by detecting bacterial number and three biofilm matrix components (carbohydrates, extracellular DNA (eDNA), and proteins). Samples comprising seven food matrix surfaces and eight food processing equipment surfaces were collected from two seafood processing plants (XY and XC) and one seafood market (CC). The results showed that the bacterial counts ranged from 1.89 to 4.91 CFU/cm2 and 5.68 to 9.15 BCE/cm2 in these surfaces by cultivation and real-time PCR, respectively. Six biofilm hotspots were identified, including four in CC and two in XY. Among the three processing environments, the amplicon sequence variants (ASVs) of Proteobacteria, Bacteroidetes, and Actinobacteria decreased with improved processing hygiene, while Firmicutes showed a decrease in the four most abundant phyla. The most prevalent bacteria belonged to genera Psychrobacter, Acinetobacter, and Pseudomonas, demonstrating the significant differences and alteration in bacterial community composition during different environments. From the biofilm hotspots, 15 isolates with strong biofilm forming ability were identified, including 7 Pseudomonas, 7 Acinetobacter, and 1 Psychrobacter. The Pseudomonas isolates exhibited the highest production of EPS components and three strong motilities, whose characteristics were positively correlated. Thus, this study verified the presence of multi-species biofilms in seafood processing environments, offering preliminary insights into the diversity of microbial communities during processing. It highlights potential contamination sources and emphasizes the importance of understanding biofilms composition to control biofilms formation in seafood processing environments.

Investigation of Heavy Metals Contamination in Indian Aquaculture Shrimp -Litopenaeus vannamei

The expanding aquaculture industry in India has raised concerns about potential environmental contaminants, particularly heavy metals in seafood products. This study aims to assess the presence and levels of heavy metals in Indian aquaculture shrimp, focusing on the widely cultivated species Litopenaeus vannamei. Shrimp samples were collected from diverse aquaculture sites across India and rigorous analytical techniques were employed to quantify the concentrations of various heavy metals. Preliminary findings indicate the potential presence of mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), copper (Cu), zinc (Zn), chromium (Cr) and nickel (Ni) in the shrimp tissues. The study explores potential sources of contamination including water quality, sediments and feed to ascertain the pathways through which these heavy metals enter the shrimp cultivation environment.