Facile ultrasonication-assisted synthesis of Purpald-functionalized silver nanoparticles for the rapid spectrophotometric detection of acetamiprid pesticide in food and environmental samples

Dispersive solid-phase extraction using polyaniline-modified zeolite NaY as a new sorbent for multiresidue analysis of pesticides in food and environmental samples

Analytical improvements shown over four interlaboratory studies of perfluoroalkyl substances in environmental and food samples

Foodborne illness associated with food service establishments is an important food safety issue in Korea. In this study, foodborne pathogens (Bacillus cereus, Clostridium perfringens, Escherichia coli, pathogenic Escherichia coli, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Vibrio parahaemolyticus) and hygiene indicator organisms [total viable cell counts (TVC), coliforms] were analyzed for food and environmental samples from foodservice establishments at schools in Gyeonggi province. Virulence factors and antimicrobial resistance of detected foodborne pathogens were also characterized. A total of 179 samples, including food (n=66), utensil (n=68), and environmental samples (n=45), were collected from eight food service establishments at schools in Gyeonggi province. Average contamination levels of TVC for foods (including raw materials) and environmental samples were 4.7 and 4.0 log CFU/g, respectively. Average contamination levels of coliforms were 2.7 and 4.0 log CFU/g for foods and environmental swab samples, respectively. B. cereus contamination was detected in food samples with an average of 2.1 log CFU/g. E. coli was detected only in raw materials, and S. aureus was positive in raw materials as well as environmental swab samples. Other foodborne pathogens were not detected in all samples. The entire B. cereus isolates possessed at least one of the diarrheal toxin genes (hblACD, nheABC, entFM, and cytK enterotoxin gene). However, ces gene encoding emetic toxin was not detected in B. cereus isolates. S. aureus isolates (n=16) contained at least one or more of the tested enterotoxin genes, except for tst gene. For E. coli and S. aureus, 92.7% and 37.5% of the isolates were susceptible against 16 and 19 antimicrobials, respectively. The analyzed microbial hazards could provide useful information for quantitative microbial risk assessment and food safety management system to control foodborne illness outbreaks in food service establishments.

Pesticides have been widely applied in agricultural practices over the past decades to protect crops from pests and other harmful organisms. However, their extensive use results in the contamination of soil, water, and agricultural products, posing significant risks to human and environmental health. Exposure to pesticides can lead to skin irritation, respiratory disorders, and various chronic health problems. Moreover, pesticides frequently enter surface water bodies such as rivers and lakes through agricultural runoff and leaching processes. Therefore, developing effective analytical methods for the rapid and sensitive detection of pesticides in food and water is of great importance. Electrochemical sensing techniques have shown remarkable progress in pesticide analysis due to their high sensitivity, simplicity, and potential for on-site monitoring. Two-dimensional (2D) carbon nanomaterials have emerged as efficient electrocatalysts for the precise and selective detection of pesticides, owing to their large surface area, excellent electrical conductivity, and unique structural features. In this review, we summarize recent advancements in the electrochemical detection of pesticides using 2D carbon-based materials. Comprehensive information on electrode fabrication, sensing mechanisms, analytical performance—including sensing range and limit of detection—and the versatility of 2D carbon composites for pesticide detection is provided. Challenges and future perspectives in developing highly sensitive and selective electrochemical sensing platforms are also discussed, highlighting their potential for simultaneous pesticide monitoring in food and environmental samples. Carbon-based electrochemical sensors have been the subject of many investigations, but their practical application in actual environmental and food samples is still restricted because of matrix effects, operational instability, and repeatability issues. In order to close the gap between laboratory research and real-world applications, this review critically examines sensor performance in real-sample conditions and offers innovative approaches for in situ pesticide monitoring.

In September 2014, a small gastroenteritis outbreak occurred in a Greek restaurant. Primary investigations by official food surveillance revealed significant hygienic problems in the premises. Food samples and environmental samples were analyzed for the presence of bacterial and viral food pathogens. Norovirus genogroup I (GI) was detected in 2 environmental samples and in mixed salad. At the same time, stool samples from patients were analyzed and norovirus GI was detected. Further investigations revealed the presence of norovirus GI on some of the restaurant employees. Comparison of nucleic acid sequences revealed full sequence homology between norovirus RNA genotype 1.2 in food, environmental and stool samples, suggesting a common source of contamination and infection. Sequence analysis of food and environmental samples was facilitated by application of a system for total RNA amplification. Despite the fact that original source of contamination could be determined doubtlessly, observed weaknesses in the food production that caused this outbreak were discussed. The mixed salad could have been contaminated either by the lettuce contaminated at primary production or by one of the food-handlers. The investigation of the path of infection is necessary for the kind of legal consequences to be directed by authorities and may contribute to measures to eliminate possible sources of food contamination.

Supramolecular solvent-based micro-extraction of pesticides in food and environmental samples

Media for Aeromonas spp., Plesiomonas shigelloides and Pseudomonas spp. from food and environment

Human noroviruses (HuNoVs) are the major cause of non-bacterial acute gastroenteritis worldwide. RT-qPCR is a widely used method to detect HuNoVs. However, the method is unable to extract a virus from environmental samples and to discriminate between infectious and non-infectious viruses. In this study, we explored a new in situ capture RT-qPCR (ISC-RT-qPCR) methodology to estimate the infectivity of HuNoV in environmental and food samples. This assay was based on capturing encapsidated HuNoV by viral receptors, followed by in situ amplification of the captured viral genomes by RT-qPCR. We demonstrated that ISC-RT-qPCR did not capture and enable signal amplification of the heat-denatured Tulane virus (TV) and HuNoVs. Therefore, ISC-RT-qPCR provides better estimates for infectivity of HuNoV than RT-qPCT. We then utilized the ISC-RT-qPCR to detect HuNoV in environmental water samples and food samples, as compared to a conventional RT-qPCR procedure. The presence of HuNoV was examined in 36 oyster samples from retail markets using by both assays for detection. The detection rates of HuNoV in gill, digestive glands, and other tissues were 33.3%, 25%, and 19.4%, respectively, by ISC-RT-qPCR; and were 5.6%, 11.1%, and 11.1%, respectively, by RT-qPCR. ISC-RTqPCR is more sensitive than RT-qPCR for the detection of HuNoV in oysters. By contrast, the HuNoV detection rate by ISC-RTqPCR is lower for environmental samples. Of the 72 water samples that tested positive for HuNoV by RT-qPCR, only 20 (27.8%) of these tested positive by ISC-RT-qPCR, suggesting that 72.2% of RT-qPCR-positive samples were unlikely to be infectious. A better detection rate by ISC-RT-qPCR in oyster samples indicates the likelihood of infectious HuNoV that accumulated in oysters, and a lower detection rate of HuNoV in environmental water by ISC-RT-qPCR, indicating that the majority of RT-qPCR-positive samples were from non-infectious viral RNA.

Chapter 8 Media for Aeromonas spp., Plesiomonas shigelloides and Pseudomonas spp. from food and environment

The Reducing Enteropathy, Undernutrition, and Contamination in the Environment (REDUCE) program focuses on identifying exposure pathways to faecal pathogens for young children in the Democratic Republic of the Congo (DRC) and on developing scalable interventions to reduce faecal contamination from these pathways. A prospective cohort study of 690 participants was conducted to investigate the association between hand, food, and environmental faecal contamination and diarrhoeal disease prevalence among young children in Walungu Territory, South Kivu, DRC. A total of 1923 hand rinse, soil, food, object, surface, stored water and water source samples were collected during unannounced spot checks after baseline enrolment and analysed for Escherichia coli. Caregiver reports of diarrhoea were obtained from children<5years at a 6-month follow-up. E.coli was detected in 73% of child and caregiver hand-rinse samples, 69% of soil samples from child play spaces, 54% of child food samples, 38% of objects and surfaces children were observed putting in their mouths, 74% of stored water samples, and 40% of source water samples. Children<5years with E. coli on their hands had significantly higher odds of diarrhoea at the 6-month follow-up (odds ratio: 2.03 (95% confidence interval: 1.05, 3.92)). The cohort study findings from the REDUCE program have shown that child hand contamination is associated with diarrhoeal disease in rural DRC, and that there is high faecal contamination in child plays spaces and food. These findings provide evidence demonstrating the urgent need to provide clean play spaces for young children and interventions targeting hand hygiene to reduce paediatric exposure to faecal pathogens.

Enantioselective analysis of pesticides in food, biological, and environmental samples by chromatographic techniques and capillary electrophoresis

Recognition of carbendazim fungicide in environmental samples by using 4-aminobenzenethiol functionalized silver nanoparticles as a colorimetric sensor

ABSTRACTStaphylococcal enterotoxin B (SEB), toxic shock syndrome, the superantigens are responsible for diseases such as staphylococcal food poisoning and toxic shock syndrome. An easy and quick system is desirable to detect toxin‐producing strains. In this report, we described standardization of a novel multiplex‐polymerase chain reaction (PCR) assay for simultaneous detection of four important genes associated with the Staphylococcus aureus viz., SEB, Tsst, genus‐specific nuclease (nuc) and Fem genes along with an internal amplification control (IAC), which has now become mandatory in diagnostic PCRs, particularly when tested on environmental or food samples. This mPCR method is sensitive enough to detect cells as low as 103 cfu/mL or /g of the food samples. When evaluated on 136 food and environmental samples, the system detected 4 SEB‐positive S. aureus strains. The S. aureus strains that have been identified to contain the SEB gene in the mPCR were unequivocally detected for the toxin expression by the TECRA kit. mPCR produced a 100% correlation with conventional identification method. As SEB and Tsst are qualified as biowarfare molecules, this system is of immense help in detecting them during emergencies of biological war and suspected outbreaks of S. aureus food poisoning directly from the food and environmental samples.PRACTICAL APPLICATIONSThe virulence‐associated genes targeted in this study are super antigenic in nature and are responsible for diseases such as staphylococcal food poisoning and toxic shock syndrome, and these molecules are also qualified as biowarfare agents. The high throughput and cost‐effective multiplex PCR method reported here could identify all these genes successfully from both artificially spiked and natural food samples and may also find its application in detection of these toxin‐producing Staphylococcus aureus from clinical and environmental samples.

Neutron activation analysis has been applied for determination of selenium in environmental and food samples. Food and environmental samples from city, industrial and agricultural zones were collected with utmost care. Samples were activated in the flux 1·1013 n·cm−2·s−1 in the CIRUS reactor of BARC, Bombay, 75-Se was separated from 6.5N HCl solution using ethyl-α-isonitrosoacetoacetate (HEINA) reagent. The decontamination studies showed the method is very selective. Selenium contents of wheat, rice, vegetables, cereals pulses etc. and of soil, water, and deposits on plants and surface were determined by the procedure developed.

Improvement of an ultrasound assisted method for the analysis of total carbohydrate in environmental and food samples