Accidental Contamination Research Articles

Estimation of the activity median aerodynamic diameter of plutonium particles using image analysis

ABSTRACT The aerodynamic radioactive median diameter (AMAD) and the absorption type are necessary information for internal exposure assessment. In 2017, at a plutonium-handling facility in the Oarai site of the Japan Atomic Energy Agency, an accidental contamination occurred, and five workers were contaminated with radioactive materials, including plutonium. In this study, some smear papers and a dust sampling filter were measured with the imaging plate, and some particles were observed with an electron microscope. The minimum AMADs for the two absorption types of plutonium were estimated for the conservative dose assessment. Two AMADs were calculated for Type M as plutonium nitrate and Type S as plutonium dioxide. Excluding the extremely large particle found in a smear sample, the AMAD estimation results showed that the minimum AMADs of plutonium nitrate from smear papers were 4.3–11.3 μm, while those of plutonium dioxide were 5.6–14.4 μm. Moreover, the minimum AMAD of plutonium nitrate from a dust sampling filter was 3.0 μm, while that of plutonium dioxide was 3.9 μm.

Antibiotic Resistance of Staphylococcus Sp. Isolated from Air, Surface, Food and Clinical samples Collected from Baghdad Hospital

Staphylococcus Sp.is the most common type of bacteria found in contamination place, we design this study to compare the contamination accident between two hospitals in Baghdad.One of them isthe Burns Specialist Hospital in the Medical CityinRusafa and another one is Al-Karama Hospital in Karkh. The samples were collected fromOperativeWard No1 (OW1), Operative Ward No2 (OW2), Consulting Pharmacy (CP), Emergency Room (ER), Reception Room (RR), Women's Ward (WW) and Men's Ward (MW).The samples were taken from inside each clinical unit, surfaces, food, and air. The results showed that the number of samples containing Staphylococcus sp. bacteria is 81, including 45 belonging to Al-Karama Burns Ward Hospital and 36 belonging to the Medical City Hospital, Burns Special Hospital. The results of Medical City Hospital showed that Staphylococcus sp.isolates resist many antibiotics, 99.99% of the isolatesfrom patient samples were resistant to(CLR, P, AMP); 92.30% of the isolates from air samples were resistant to(P, MET) and 85.71%of isolates from surfaces and food samples were resist for (AMP, MET). Also the results of Al-KaramaHospital showed that the highest resistance in the staphylococcus sp.isolateswere in patient samplesfor (AMP, SXT), in surface samples for (E), in food samples for (E,P) and in air samples for (P) and the resistance rates were 100% to all these antibiotics.

Preliminary study on species authentication in poultry meat products by next-generation sequencing

The growing demand for poultry meat and the complexity of the supply chain affect traceability. Therefore, the aim of this study was to apply DNA metabarcoding to verify the labelling compliance of multi-species poultry meat commercial products. Overall, the molecular identifications conducted in this study confirm that all products contain the species declared in the label and all the non-conformities regard the presence of one or more undeclared meat species. In particular, undeclared species, such as pig and cattle, were highlighted in 8/13 of the samples. Such pattern could be due to technological purposes or accidental contamination linked to inappropriate sanitation practices during processing. However, the presence of undeclared species can affect the ability to choose for consumers with of specific needs (e.g., ethic, religious) or health risk and should be not neglected. Results of this study show that metabarcoding is a promising tool to identify meat species in mixtures. Therefore, its application by food industry and competent institutions, could help to innovate the food management system with the creation of a favorable environment for the protection and respect of the consumer needs. • NGS Metabarcoding is powerful tool to authenticate multi-species meat products. • The presence of unexpected species was highlighted. • Undeclared species have ethic and religious implications. • Metabarcoding could trace environmental and hygienic-sanitary conditions. • Food management system can be improved by the application of advanced approaches.

High sensitivity on-site early warning system monitoring of pesticides by photo-induced fluorescence

This paper describes the prototype of an on-site High Sensitivity Early Warning Monitoring System, using Photo-Induced Fluorescence, for pesticide monitoring in natural waters (HSEWPIF). To obtain a high sensitivity, the prototype was designed with four main features. Four UV LEDs are used to excite the photoproducts at different wavelengths and select the most efficient one. Two UV LEDs are used simultaneously at each wavelength to increase the excitation power and then the fluorescence emission of the photoproducts. High-pass filters are used to avoid the saturation of the spectrophotometer and to increase the signal-to-noise ratio. The HSEWPIF prototype also employs UV absorption to detect any occasional increase of suspended and dissolved organic matter, which could disrupt the fluorescence measurement. The conception of this new experimental set-up is explained and described, then analytical applications are carried out online for the determination of fipronil and monolinuron. We obtained a linear calibration range from 0 to 3 μg mL−1 with limits of detection of 1.24 ng mL−1 for fipronil and 0.32 ng mL−1 for monolinuron. A mean recovery of 99.2% for fipronil and 100.9% for monolinuron show that the method is accurate, moreover a standard deviation of 1.96% for fipronil and 2.49% for monolinuron show that the method is repeatable. Compared to other methods for the determination of pesticides by photo-induced fluorescence, the HSEWPIF prototype has good sensitivity with better limits of detection, and good analytical performances. These results show that HSEWPIF can be used for monitoring pesticide in natural waters to protect industrial facilities against accidental contamination.

Review of Urban Drinking Water Contamination Source Identification Methods

When drinking water flows into the water distribution network from a reservoir, it is exposed to the risk of accidental or deliberate contamination. Serious drinking water pollution events can endanger public health, bring about economic losses, and be detrimental to social stability. Therefore, it is obviously crucial to research the water contamination source identification problem, for which scholars have made considerable efforts and achieved many advances. This paper provides a comprehensive review of this problem. Firstly, some basic theoretical knowledge of the problem is introduced, including the water distribution network, sensor system, and simulation model. Then, this paper puts forward a new classification method to classify water contamination source identification methods into three categories according to the algorithms or methods used: solutions with traditional methods, heuristic methods, and machine learning methods. This paper focuses on the new approaches proposed in the past 5 years and summarizes their main work and technical challenges. Lastly, this paper suggests the future development directions of this problem.

<p><strong>Tropane alkaloids and the potential for accidental or non-accidental mass outbreaks of anti-cholinergic toxidrome</strong></p>

In December 2022 a large outbreak of anti-cholinergic toxidrome was reported in Australia associated with contamination of baby spinach leaves with Datura stramonium. Over 100 individuals around Australia experienced symptoms consistent with intoxication with the primary plant derived tropane alkaloids scopolamine, hyoscyamine and atropine. Tropane alkaloids are part of a wider group of incapacitating chemical substances that includes the chemical weapon BZ that results in the characteristic anti-cholinergic toxidrome. Human food production and manufacturing processes are prone to accidental and non-accidental contamination with tropane alkaloids, and food quality standards and measures are essential to protecting food security where incorporation of tropane alkaloids is possible. While mass non-accidental contamination of human food production and manufacture is a possibility, historically exposure scenarios involving tropane alkaloids have usually been limited to small scale poisoning events dating back to antiquity. This article summarises the risks of accidental and non-accidental exposure to tropane alkaloids with particular focus on the potential for mass exposure events.

Blister Beetle Induced Keratoconjunctivitis

Blister beetle-induced keratoconjunctivitis is the rarest presentation. Blister beetle also known as Rove beetle, belongs to the class insecta and order – coleoptera.[1] The species paedrussabeus which is also called as Nairobi fly is easily recognized by its characteristic red, black and dark green colour.[1] This paedrus genus produces the chemical toxin called paedrin which is responsible for characteristic dermatological and rare ocular manifestations. Dermatitis in the form of violaceus painful blisters with intense itching is its most commonest manifestation. Ocular manifestations are very rare and occur only secondary to accidental contamination of eyes with the fingers which had contact with toxic chemicals from the blister site. Here, in this case report we will be discussing one such rare case of keratoconjunctivitis due to blister beetle.

Doping control in horses in the Czech Republic in 2010-2019

The aim of this study was to evaluate data on doping controls in racehorses over a given ten-year period, primarily to identify positive findings and to summarise recommendations for the prevention of accidental contamination with prohibited substances, where appropriate. Data on doping controls of racehorses in the Czech Republic from 2010 to 2019 were obtained from the archives of the Jockey Club of the Czech Republic. For each year, the total number of horses starting at races held in the Czech Republic, the number of horses tested, and the results of the doping controls were determined. Data on the type of samples, positive findings and statements from responsible persons about the cause of the positive finding were recorded. During the monitoring period, 11,852 horses competed in races in the Czech Republic and 641 of them underwent a doping control. Blood was taken from 356 horses as the sample for testing and urine was collected from 285 horses. A total of 13 positive findings (2.03% of the 641 tested) were found during the period, namely of morphine, caffeine, theobromine, omeprazole sulphide, furosemide, clenbuterol, norketamine, ritalinic acid, dexamethasone, flunixin, hydroxylidocaine and oripavine. The most common cause, in a total of seven horses, was confirmed as suspected feed contamination. Prevention of positive doping results in our circumstances should therefore be directed primarily towards compliance with proper feed and stable management.

A field case of pig poisoning by accidental feed contamination by alkaloid-rich lupin seeds

ABSTRACT This paper describes a field case of pig poisoning due to accidental contamination by alkaloid-rich lupin seeds of the grain legume mixtures used as protein sources in the feeds. The accident happened in Northern Italy in 2016, involved several farms and affected 2170 pigs of different categories (pregnant or lactating sows, gilts and fattening pigs). The observed clinical symptomatology was spanning from partial or total feed rejection to depression, recumbency, hypersalivation, vomiting and eventually death by necropsy by torsion of the stomach and gastro-enteric bloat. In feed formulations, the quinolizidine alkaloids (QAs), quantified by a GC-MS method, spanned from 0.051 to 1.245 mg/g. There was a relationship between the QAs content and the severity of clinical symptomatology: at a higher concentration, the outcomes were a larger incidence of clinically affected individuals (up to 50%) and a more severe clinical picture with mortality (up to 20%), which involved especially lactating sows.

Atropine and scopolamine occurrence in spices and fennel infusions

Tropane alkaloids (TAs) are toxic anticholinergic compounds that appear due to accidental contamination of foods with TA-producing plants. Atropine and scopolamine are the most common TAs and their maximum levels in certain foodstuffs have been recently regulated, including food supplements. TAs occurrence in commercial products and the transfer ratio to herbal infusions prepared from contaminated spices are of interest for exposure assessment of consumers. In this study, the occurrence of atropine and scopolamine was investigated in a total of 51 commercial spices of 6 types (ginger, cloves, fennel, cumin, aniseed, coriander) and a mix of spices and herbs (curry) purchased in Portugal (19 samples) and Spain (32 samples) in 2021. Results evidenced that more than half of the samples analysed (67%) were contaminated with one or both analytes. Fennel, cloves and coriander showed the highest concentrations ranging between 5-31 μg/kg, 8–28 μg/kg and 5–45 μg/kg, respectively, for the sum of atropine and scopolamine. On the other hand, the transfer ratio of the target analytes found in four naturally contaminated fennel samples was studied. Infusions were prepared according to International Standard ISO 3103 protocol, and a transfer ratio between 64 and 88% for atropine and between 47 and 57% for scopolamine was found.

Evaluation of the Bacterial Load in the Raw Dairy Products in Baghdad, Iraq.

Milk and cheese were recognized as highly nutritious food due to their high protein, fat and minerals (calcium, phosphorus, iron, and vitamins). Accidental contamination of food through the handlers could have resulted in many kinds of bacteria especially Staphylococcus aureus in the dairy products. Therefore, this study aimed to study variation in bacterial isolation percentage and the bacterial counts in raw milk and locally produced soft cheese in local markets in Baghdad. A total of 150 samples of raw milk and local soft cheese (75 for each) were collected from different regions of Baghdad city from October 2020 to July 2021 to study the evaluation of bacterial contamination. The isolation percentage of total coliform, Fecal coliform, Escherichia coli and Staphylococcus aureus in the raw milk were 82, 69, 54 and 42%, respectively. While in the soft cheese, the isolation percentage for coliform, Fecal coliform, Escherichia coli and Staphylococcus aureus were 90, 74, 60 and 45%, respectively. Furthermore, high percentages of bacterial isolation were recorded during summer. The recorded data showed significant (P<0.05) variation for both raw and soft cheese according to months, and soft cheese had a higher isolation percentage than the raw milk samples. The average values of bacterial count values that were isolated from October to February in the raw milk of the total coliform, fecal coliform, E. coli and Staph aureus were 5.57, 4.25, 3.77 and 2.94 cfu log10/mL respectively, which were recorded during the cold months. While the recording of the average values from March to July as hot months were 6.02, 5.02, 5.22 and 3.23 CFU log10/mL, respectively. The average bacterial values in the soft cheese were 6.02, 5.03, 4.97 and 3.67cfu log10 /g, respectively, from October to February and were significantly (P<0.05) less than the summer from March to July, which recorded 7.17, 6.32, 5.01 and 4.15cfu log10/g respectively. The high contamination found in the soft cheese and during hot months compared with raw milk and cold months, respectively, is a sign of unsanitary manufacturing conditions such as post-process contamination, high temperature in summer, and lack of refrigeration during long-distance transportation.

Peelable Nanocomposite Coatings: "Eco-Friendly" Tools for the Safe Removal of Radiopharmaceutical Spills or Accidental Contamination of Surfaces in General-Purpose Radioisotope Laboratories.

Radioactive materials are potentially harmful due to the radiation emitted by radionuclides and the risk of radioactive contamination. Despite strict compliance with safety protocols, contamination with radioactive materials is still possible. This paper describes innovative and inexpensive formulations that can be employed as 'eco-friendly' tools for the safe decontamination of radiopharmaceuticals spills or other accidental radioactive contamination of the surfaces arising from general-purpose radioisotope handling facilities (radiopharmaceutical laboratories, hospitals, research laboratories, etc.). These new peelable nanocomposite coatings are obtained from water-based, non-toxic, polymeric blends containing readily biodegradable components, which do not damage the substrate on which they are applied while also displaying efficient binding and removal of the contaminants from the targeted surfaces. The properties of the film-forming decontamination solutions were assessed using rheological measurements and evaporation rate tests, while the resulting strippable coatings were subjected to Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and tensile tests. Radionuclide decontamination tests were performed on various types of surfaces encountered in radioisotope workspaces (concrete, painted metal, ceramic tiles, linoleum, epoxy resin cover). Thus, it was shown that they possess remarkable properties (thermal and mechanical resistance which permits facile removal through peeling) and that their capacity to entrap and remove beta and alpha particle emitters depends on the constituents of the decontaminating formulation, but more importantly, on the type of surface tested. Except for the cement surface (which was particularly porous), at which the decontamination level ranged between approximately 44% and 89%, for all the other investigated surfaces, a decontamination efficiency ranging from 80.6% to 96.5% was achieved.

Risk of Poisoning from Garden Plants: Misidentification between Laurel and Cherry Laurel.

The misidentification between edible and poisonous plants is an increasing problem because of the new trend to collect wild plants, especially by amateur collectors who do not have the botanical skills to distinguish between edible and toxic species. Moreover, morphologically similar species are sometimes responsible for accidental contamination or used in the intentional adulteration of products for human and animal consumption. Laurus nobilis L. (laurel) and Prunus laurocerasus L. (cherry laurel) are typical ornamental shrubs of the Mediterranean region. Laurel is considered a non-toxic plant, widely used as flavorings. Conversely, cherry laurel leaves, morphologically similar to those of laurel, contain toxic cyanogenic glycosides. Considering this, the aim of this study was to carry out an in-depth evaluation of laurel and cherry laurel leaves by using light and scanning electron microscopy coupled with three step phytochemical analyses (qualitative and quantitative colorimetric assays and liquid chromatography). This allowed to highlight the distinguishing features of plant species investigated features such as the venation pattern, presence/absence of nectaries, calcium oxalate crystals, secretory idioblasts, and cyanogenic glycosides. Concluding, this multidisciplinary approach can be useful for the identification of plants but also fragments or pruning residues containing cyanogenic glycosides, in quality control tests, intoxications, and criminal cases.

The Practices and Attitudes of Saudi Plastic Surgeons in Managing Contaminated Autologous Grafts.

Background:The use of autologous grafts is a standard reconstructive option in plastic surgery. The absence of a well-established protocol for decontamination after accidental contamination increases the risk of postoperative infection. We aimed to explore the current practice and decontamination methods among Saudi plastic surgeons. This would help develop a well-established, unified method of decontamination intraoperatively.Methods:A validated self-administered questionnaire cross-sectional study was conducted in February 2022. The questionnaire was distributed through social media to all board-certified plastic surgeons in Saudi Arabia. The questionnaire was designed to obtain data on incidents, treatment preferences, and management of autograft contamination.Results:A total sample size of 61 participants was included, with an overall response rate of 64.58%. Out of the 61 respondents, 73.8% (n = 45) had previously experienced graft contamination. Regarding the methods of graft contamination, the most common way was accidentally dropping the graft on the floor (39.7%, n = 25). The majority of the surgeons answered that they decontaminated the graft using povidone-iodine (44.6%, n = 29) and then used it (45.9%, n = 28). The lower extremity area was the most common anatomical location having surgery at the time of the graft contamination, accounting for 32.5% of the cases (n = 25).Conclusions:Our study indicates that graft contamination is a common occurrence among our population, but we lack national guidelines on dealing with these situations. Although most responders used adequate decontamination methods, the lack of standardization could pose a risk to patients.

Food safety concerns and food defense support: a cross-cultural study

Consumers face the risk that their food is unsafe because of natural and accidental contamination (traditional food safety problems) or deliberate contamination (food defense problems). Coordinated international efforts with leadership from developed countries could help reduce these food risks. If consumers within or between countries have different attitudes about the risks, it may be difficult to generate sufficient political support for building an international food safety system. A unique consumer survey of adults in the US, the UK, Spain, Italy, Germany, and Japan identified consumer attitudes about traditional food safety and food defense. Concerns about traditional food safety, confidence in the system to prevent intentional contamination, and funding allocations between food safety and food defense were examined in models with two sets of cultural control measures. Many people perceived food safety to be different from food defense. Food safety concerns were linked to gender, age, presence of children, education, income, power distance, uncertainty avoidance, and masculinity. Food defense confidence was associated with gender, age, power distance, and uncertainty avoidance. Funding allocations were examined in two models and power distance, uncertainty avoidance, and individualism were significant. Although it was expected that low concerns about food safety and low confidence in food defense would increase the allocation share for food defense, this was not confirmed in the data. Many differences were noted between countries, showing the importance of culture for understanding attitudes toward food risks. Although both sets of cultural measures made significant contributions, neither was judged to be superior to country dummy variables. Given the variations found in attitudes toward food safety and food defense, creating an international solution to reduce food risks will be difficult.

A microfluidic diagnostic device with air plug-in valves for the simultaneous genetic detection of various food allergens

The identification of accidental allergen contamination in processed foods is crucial for risk management strategies in the food processing industry to effectively prevent food allergy incidents. Here, we propose a newly designed passive stop valve with high pressure resistance performance termed an “air plug-in valve” to further improve microfluidic devices for the detection of target nucleic acids. By implementing the air plug-in valve as a permanent stop valve, a maximal allowable flow rate of 70 µL/min could be achieved for sequential liquid dispensing into an array of 10 microchambers, which is 14 times higher than that achieved with the previous valve arrangement using single-faced stop valves. Additionally, we demonstrate the simultaneous detection of multiple food allergens (wheat, buckwheat, and peanut) based on the colorimetric loop-mediated isothermal amplification assay using our diagnostic device with 10 microchambers compactly arranged in a 20-mm-diameter circle. After running the assays at 60 °C for 60 min, any combination of the three types of food allergens and tea plant, which were used as positive and negative control samples, respectively, yielded correct test results, without any cross-contamination among the microchambers. Thus, our diagnostic device will provide a rapid and easy sample-to-answer platform for ensuring food safety and security.

The dangers of reused personal protective equipment: healthcare workers and workstation contamination

BackgroundPersonal protective equipment (PPE) is essential to protect healthcare workers (HCWs). The practice of reusing PPE poses high levels of risk for accidental contamination by HCWs. Scarce medical literature compares practical means or methods for safe reuse of PPE while actively caring for patients.MethodsIn this study, observations were made of 28 experienced clinical participants performing five donning and doffing encounters while performing simulated full evaluations of patients with coronavirus disease 2019. Participants' N95 respirators were coated with a fluorescent dye to evaluate any accidental fomite transfer that occurred during PPE donning and doffing. Participants were evaluated using blacklight after each doffing encounter to evaluate new contamination sites, and were assessed for the cumulative surface area that occurred due to PPE doffing. Additionally, participants' workstations were evaluated for contamination.ResultsAll participants experienced some contamination on their upper extremities, neck and face. The highest cumulative area of fomite transfer risk was associated with the hook and paper bag storage methods, and the least contamination occurred with the tabletop storage method. Storing a reused N95 respirator on a tabletop was found to be a safer alternative than the current recommendation of the US Centers for Disease Control and Prevention to use a paper bag for storage. All participants donning and doffing PPE were contaminated.ConclusionPPE reusage practices pose an unacceptably high level of risk of accidental cross-infection contamination to healthcare workers. The current design of PPE requires complete redesign with improved engineering and usability to protect healthcare workers.

Domain Knowledge-Based Evolutionary Reinforcement Learning for Sensor Placement.

Reducing pollutant detection time based on a reasonable sensor combination is desirable. Clean drinking water is essential to life. However, the water supply network (WSN) is a vulnerable target for accidental or intentional contamination due to its extensive geographic coverage, multiple points of access, backflow, infrastructure aging, and designed sabotage. Contaminants entering WSN are one of the most dangerous events that may cause sickness or even death among people. Using sensors to monitor the water quality in real time is one of the most effective ways to minimize negative consequences on public health. However, it is a challenge to deploy a limited number of sensors in a large-scale WSN. In this study, the sensor placement problem (SPP) is modeled as a sequential decision optimization problem, then an evolutionary reinforcement learning (ERL) algorithm based on domain knowledge is proposed to solve SPP. Extensive experiments have been conducted and the results show that our proposed algorithm outperforms meta-heuristic algorithms and deep reinforcement learning (DRL).

Needle stick injury among the dental students in the Qassim University, KSA: It’s Prevalence, student’s Knowledge and attitude

Needle stick injuries (NSI) are the commonest route by which blood borne viruses and/or infections such as HIV, Hepatitis B and C are transmitted from patients to health care workers (HCW) dental students are also at risk of such infections and injuries due to accidental contamination during their practical occupational exposure. There is hardly any information regarding the knowledge and experiences of NSI among dental students in Saudi Arabia&#x0D; Aim: To assess the knowledge, attitude, and prevalence of NSIs among dental students in Qassim university.&#x0D; Design: Descriptive cross-sectional study.&#x0D; Setting: dental clinics of Qassim University. The population included undergraduate students (3rd ,4th,5th year) and intern’s dentists/College of Dentistry /Qassim University.&#x0D; Result: In the present study. A total number of 98 student participated 56.1% were female and 43.9% were male. A total of 27.6% participants had an NSI during their clinical training. Also, 83% of the students considered hepatitis B, hepatitis C, and HIV to be transmitted by NSIs.&#x0D; Conclusion: Although the level of knowledge on the risk of cross-infection from NSI was high, there was decreased awareness on the means of prevention and protocol.&#x0D; Keywords: NSI, Awareness, cross infection, prevalence, hazard.

Multi-criteria method for the realistic placement of water quality sensors on pipes of water distribution systems

This paper aims to solve three issues frequently present in the optimal placement of water quality sensors for protecting water distribution systems (WDSs) from both accidental and intentional contamination, namely i) computational intractability of the optimization problem as the size of the WDS increases, ii) unrealistic assumption that sensors are positioned at nodes, rather than on system pipes, and iii) neglecting site-specific practical conditions impacting on sensor installation. The three drawbacks were tackled by i) restraining the optimization to the hydraulic/topological-wise most important pipes, ii) introducing dummy nodes in the middle of these pipes as potential sensor locations, iii) applying a multi-criteria decision-making tool incorporating urbanistic and economic factors for selecting the most effective sensor locations. The method is tested on the WDS of the town of Parete (Italy), showing the manyfold benefits of the solution obtained.