Plastic Water Research Articles

Experimental study on the effect of plastic waste strips and waste brick powder on strength parameters of expansive soils

Ethiopia has an abundance of expansive soils. This type of soil is weaker, having low strength and load-resisting characteristics in nature due to its difficulty in volume change when exposed to water. As a result, when saturated with water, the volume of such soils expands and contracts during dry seasons. In civil infrastructure construction, such soil should be removed or improved to be used as foundation soil. However, removing the soil leads to the extra costs of construction. On the other hand, improving requires increasing the stiffness and load-carrying capacity of the road by treating it with stabilizers, which help achieve low cost and good performance. This study aimed at treating such soils with waste-disposed materials to improve the soil's resistance to pressure and to reduce pollution. In this study, locally available expansive soil is treated with brick waste powder (20, 30, and 40 %) and waste plastic strips with (0.25 %, 0.5 %, and 0.75 %) percentages in weight. Disposed plastic water bottles are used. Atterberg limits, compaction, CBR, and unconfined compressive strength were performed to find an optimum percentage of mixes. Many trials were done by varying the percentages of PWS (plastic waste strips) and BP (brick powder). At the addition of 0.75% PWS and 30% BP, a significant change was observed with a considerable improvement in free swell, CBR, and unconfined compressive strength values. The study reveals plastic waste strips and brick waste powder were found to increase the strength qualities of expansive soils. This could pave the way for the use of waste materials in pavement construction while also lowering the environmental pollution.

The Dosimetric Effect of MRI Positive-Contrast Markers vs. Negative-Contrast Fiducial Markers on Proton Radiation

The usage of magnetic resonance imaging (MRI) has been limited in prostate cancer radiation because a lack of effective positive-signal MRI fiducial markers (FM). The FM used in our prostate clinic (gold anchor [GAFM] for photons; carbon [CFM] for protons) are not reliably localized with MRI. The uncertainty of FM localization using MRI affects spatial accuracy of the target volume planning and limits optimum patient treatment positioning. Current FM generate 10-38% proton dose perturbation. We hypothesize that the novel multimodality positive-signal FM (C4 Nova [C4NFM], are visible on kilovoltage, computed tomography, and MR images, with a reduced imaging artifact versus GAFM or CFM) can potentially improve the precision and accuracy of radiotherapy and present more acceptable proton dose perturbation. Herein, dose perturbation of different FM was compared.The negative- (GAFM [0.38 × 8.4 mm], CFM [0.59-0.88 × 3 mm]) and positive-signal (C4NFM-5 [1.0 × 5.5 mm], C4NFM-10 [1.0 × 9.8 mm]) MRI FM were tested. Markers were arranged inside plastic water material at the center of a passively scattered spread-out Bragg peak (160 MeV, range 16 cm, SOBP 10 cm). The dose was measured using radiochromic film placed at 0, 2, 5, 10, 20, 30, and 40 mm downstream from the markers. The FM were oriented perpendicularly (PER) or parallel (PAR) relative to the beam axis. The films were scanned using Epson 11000XL flatbed scanning in 300 depi resolution and were further analyzed using imageJ software.The proton dose perturbation is associated with marker type, orientation, and the depth of measurement (Table). Proton dose perturbation increased with the depth away from the FM before it gradually decreased to zero. Less dose perturbations were observed at the PER vs. PAR orientation. GAFM induced higher dose perturbation versus CFM and C4NFM in both the maximum value and the perturbation depth. Compared to CFM, C4NFM produced a lower maximum dose perturbation (1.4% vs. 3.0% at PER; 5.7% vs. 7.9% at PAR), and shallower perturbation depth (5 vs. 20 mm at PER). Notably, both the longer C4NFM-10 and shorter C4NFM-5 produced the same dose perturbation in both maximum value (5.7% at PER) and the depth (20 mm).C4 Nova MRI positive-contrast fiducial markers have the least proton dose perturbation effect compared with gold and carbon MRI negative-contrast markers. These data may serve as evidence for future clinical trials to study the benefit of MRI from treatment planning to delivery using positive MRI signal C4 Nova FM in preserving tumor control while decrease radiation related toxicities in patients with prostate cancer.

Effects of chronic exposure to usual and high doses of Bisphenol A on cardiac arrhythmias, electrophysiology, and autonomic modulation

Abstract Background Bisphenol A (BPA) is a synthetic compound found in plastic bottles, sports equipment, or water pipes. The continuous and inevitable human exposure to BPA has been related to increased cardiovascular risk. In experimental studies, acute exposure to high BPA doses was associated with ventricular arrhythmias. However, the effects of chronic exposure to usual BPA doses (i.e., relevant for usual human exposure) on cardiac arrhythmogenicity have not been properly assessed. Purpose We aimed to assess the effects of chronic exposure to high and usual BPA doses on cardiac arrhythmias, electrophysiology, and autonomic modulation in rats. Methods Adult female Wistar rats were randomized into 3 groups: Control, BPA, and BPA-HD (n=7 each). BPA and BPA-HD rats received 50 μg/kg/day and 25 mg/kg/day of BPA, respectively, for 9 weeks. Rats were implanted with radiotelemetry ECG devices and 24-h ECG recordings were performed prior to and after application of transesophageal atrial burst pacing (4,000 stimuli/min for 20 s; 15 cycles). Heart rate variability (HRV) parameters and atrial and ventricular arrhythmias (i.e., atrial premature beats [APB], atrial fibrillation [AF], ventricular premature beats [VPB], ventricular tachycardia/fibrillation [VT/VF]) were assessed based on the 24-h ECG recordings. The left atrium was then collected and atrial depolarization velocity and action potential duration to 90% (APD90) and 50% (APD50) of complete repolarization were measured. Results Mean heart rate (p=0.48), the number of VPB (p=0.90), AF inducibility (p=0.68), and atrial action potential parameters (all p>0.05) were all similar between the 3 groups. None of the animals presented VT/VF. There was no significant difference in the number of atrial or ventricular arrhythmic events nor in the HRV parameters between BPA and Control (all p>0.05). However, BPA-HD presented a significantly higher number of APB both prior to (p=0.02) and after (p=0.04) atrial pacing, and a significantly higher number of post-pacing spontaneous AF episodes (p<0.01) compared to Control. The parasympathetic indexes SDNN, RMSSD, pNN5, and the NHF of the HRV spectrum were all significantly higher (all p<0.05), whereas the LF/HF ratio, an index of sympathetic and parasympathetic interactions, was significantly lower (p=0.01) in the BPA-HD compared with the Control rats. Conclusions In rats, chronic exposure to BPA doses relevant for usual human exposure was not associated in any significant change in cardiac arrhythmogenicity, electrophysiology, or autonomic modulation. However, high-dose BPA exposure, such as that occurring in workers in the plastics industry, led to significant increase in atrial arrhythmogenicity, including AF, that did not seem to be related to atrial electrophysiology changes. Instead, given the strong atrial proarrhythmic effects of vagal hyperactivity, this effect could be linked to the significant increase in vagal modulation induced by high-dose BPA exposure. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by a grant of the Romanian Ministry of Education and Research, CNCS – UEFISCDI

Progress on the photo aging mechanism of microplastics and related impact factors in water environment

As an emerging pollutant, microplastics (MPs, plastic particles with size 5 mm) pollution in water has acquired extensive attention in recent years due to their small particle size and stable properties, which can act as a carrier for pollutants in water environment and have toxic hazards to aquatic organisms. After entering into water environment, MPs are readily undergone varied types of weathering processes (i.e., hydrolysis, photo oxidation, mechanical abrasion, and biodegradation), leading to shifted surface morphology (i.e., surface roughness, specific surface area, and size) and physicochemical properties (i.e., melting temperature, surface charge, molecular weight, crystallinity, and hydrophobicity). Among different weathering processes of MPs in water, sunlight induced photo aging process has been considered as primary contributor, which will further impact the MPs behaviors, such as aggregation and deposition in water column, adsorption to organic and inorganic pollutants, leaching of additives, as well as toxicity to organisms in water. From the perspective of MPs aging mechanism, photo aging process of MPs in water environment is a free radical associated chain reaction process and readily to be affected by polymer types, plastic additives, halogen ions, and natural organic matters. These components are generally photochemical activated and prone to involved in the direct or free radical associated indirect photo aging process processed. However, limited information has referred the impact of plastic additives and water constitutes on the long term weathering process for MPs in water, which will pose a great difference between laboratory-accelerated weathering and long-term natural weathering. Studying the photo aging mechanism of MPs in water environment is of great significance for evaluating their formation process and potential ecological risks. Based on the above considerations, we systematically reviewed the photo aging and fragmentation processes of MPs in water environment. The content of this work contains: (1) Photo aging mechanism and changes of MPs physicochemical properties during aging process in water. Research results revealed that photo aging process could affect the molecular arrangement and mechanical properties of MPs, and further fragment into smaller size secondary MPs even in nano-scale particles, which is important to explain the formation of MPs in current water environment. (2) Critical effect of plastic properties, such as polymer type, size, and plastic additives on the aging of MPs in water; for the impact of plastic additives on the aging process of MPs, results in this work suggested that photo aging mechanism of MPs could be modified due to the presence of plastic additive (i.e., antioxidant and colorant). (3) Role of water constitutes (i.e., Cl−, Br, and NOM) on the photo aging process of MPs in water. The results emphasized the multiple impacts of water constitutes (halogen ions and natural organic matter) in the photo aging process of MPs in the water environment, illustrating that MPs may have different aging time and mechanisms in different water matrices. Moreover, impact of microorganism induced biodegradation for MPs in water is also proposed. In further study, more concentration should be concerned on the combined effects of plastic additives and water quality conditions on the aging process of MPs, which is helpful to shorten the distance between laboratory accelerated weathering and long-term aging process of MPs in natural waters. Besides, results of this paper can also provide theoretical support for comprehensively and systematically assessing the environmental behavior, toxicological effects and ecological risks of aged MPs in natural water environment.

Characteristics of nano-plastics in bottled drinking water

Plastic pollution in water is threatening the environment and human health. Previous relevant studies mainly focus on macro and micro plastic pollutions and their characteristics. Little is known about the extent and characteristics of nano-scale plastics in our drinking water systems, mainly due to difficulties in their isolation and analysis. These nano-plastics may pose higher risk to human health than micro-plastics. Here we report the collection and analysis of organic nanoparticles from commercial bottled water of two brands. Novel nano-plastic particle imaging and molecular structure analysis techniques have been applied. The findings show the existence of organic nanoparticles, and a likely source has been identified to be the degradation of plastic water bottles.

Social Comparison Information Influences Intentions to Reduce Single-Use Plastic Water Bottle Consumption.

Single-use plastic consumption is at an all-time high and threatens environmental and human health. College campuses in particular serve as a hub for single-use plastics due to their convenience for students on the go. The present research tests whether social comparison information can influence self-perceptions of single-use plastic consumption and motivate behavior change within the college campus environment. In a controlled experiment, we measured college students' existing plastic water bottle usage and gave them false feedback about their behaviors and relative standing to their classmates: participants in comparison conditions learned they were either above or below average in their plastic water bottle sustainability behaviors. Results indicated that (relative to a no-comparison control), being above average at water bottle sustainability led students to be more satisfied with their sustainability efforts. However, either kind of comparison information (i.e., being above or below average) led to greater behavioral intentions to reduce single-use plastic water bottle consumption in the future. This study highlights how comparison information can be used to motivate sustainable behavior change with regards to single-use plastics.

Density Figure of Aedes Aegypti Larvae and Community Participation in Prevention of Dengue Hemorrhagic Fever (DHF)

The density of Aedes aegypti mosquito larvae is a risk factor for Dengue Hemorrhagic Fever transmission. Density Figure (DF) is a measurement to determine the success of Aedes aegypti control with four leading indicators (House Index/HI, Container Index/CI, Breteau Index/BI, and Larva Free Figure/ABJ). In addition, community participation, manifested in the Mosquito Nest Eradication Movement, is also essential to prevent and control DHF. This study determined the density figure of mosquito larvae and community participation in the DHF prevention in Oesapa Urban Village, Kupang City, in 2021. This research was a descriptive research type with a total sample of 99 households. Data univariably analysis on water container material, water container type, water container cover presence, and community participation. The results showed that most of the respondents used plastic water container material (57.51%), TPA container type (55.09%), and presented uncovered water container (63.05%). The DF of Aedes aegypti mosquito larvae was in the high category with HI (35.36%), CI (51.86%), BI (324.42%), and ABJ of 64.65%. Therefore, the community should be more aware and consistent to apply PSN-DHF, focusing on 3M Plus implementation to reduce the incidence of DHF.

The Ethical Implications of Reusing External Fixation Systems: A Used Car or A Plastic Water Bottle?

The reuse of external fixation systems raise several important ethical considerations. Reusing external fixators can decrease costs, but questions emerge about who owns the implant, who will benefit from the savings, and the need to disclose the use of reprocessed parts. In addition, there are concerns relating to infection, as well as humanitarian and environmental considerations that must be weighed when deciding whether to implement a reprocessing program for external fixators.

Radiation Oncology Exhibits

Purpose: The Australian Clinical Dosimetry Service (ACDS) has been auditing Australian and New Zealand radiotherapy providers for nearly 10 years building the National Dataset of audit measurements. The audits have uncovered numerous issues with varying significance. This paper will present an update of the ACDS audits including trends within the National Dataset and recent audit findings and will then cover recent audit of more advanced modalities such as SRS, SBRT, VMAT and adaptive radiotherapy. The presentation will conclude with a summary of the COVID-19 impact on the ACDS. The audits demonstrably improve the treatment quality and safety for patients undergoing radiotherapy. Methods and Materials: The ACDS began life in November 2010 and has developed a comprehensive three level auditing service which has expanded beyond Australia's borders. To minimize dosimetric uncertainties the ACDS has been using Computerized Imaging Reference Systems (CIRS)1 plastic water and phantoms across all on-site audits. As phantom complexity increased to meet auditing needs, CIRS was engaged to produce bespoke phantoms for the ACDS. The most recent examples of this are the Stereotactic Radio-Surgery (SRS) head phantom, SBRT, and a thorax customized for stereotactic ablative radiotherapy (SABR) auditing. Results: Audits provide two key outcomes for participating facilities. The first is that independent measurements demonstrate whether the facility's predicted dose is being delivered to the phantom within an acceptable tolerance. For an out-of-tolerance finding the ACDS works with the facility to resolve any discrepancies on the day of audit. Examples include inaccurate data entry in a planning system or inaccurate phantom positioning. Sometimes, however, there may be a systemic issue with calculation algorithms. The National Dataset has enables the ACDS to identify characteristic behavior of certain equipment combinations. As the ACDS perform more audits, the statistical power of the dataset increases and trends can be identified. This is the second key capability which a mature auditor provides to the auditee. Conclusion: The ACDS has development a coherent and successful auditing service which is proactively responding to changing technologies and environment.

Trihalomethanes formation enhanced by manganese chlorination and deposition in plastic drinking water pipes

Residual manganese(II) in finished water undergoes further oxidation and deposition in drinking water distribution systems (DWDS), and Mn deposits can function as sites for accumulating organic and inorganic pollutants. This study aims to explore how Mn transformation and deposition affect the formation of disinfection byproducts (DBPs) in chlorinated DWDS, and trihalomethanes (THMs) was selected as a representative DBP. In a 100 μg/L Mn system, regulated THMs (chlorinated/bromated-THMs) increased by over 20% higher than Mn-free system after 150-day operation; when 50 μg/L iodide (I−) entered pipe systems after 150 days, iodinated THMs (I-THMs) in 100 μg/L Mn system increased by over 30% compared with Mn-free system. These promotions were attributed primarily to the accumulation of biomolecules and organic substances by tight and hard chlorinated Mn deposits. The residence of inactivated cells and the bridging role of surface Mn(III) in Mn deposits increased the quantity of THM precursors in DWDS. Furthermore, the rapid catalytic oxidation of Mn(II) by preformed Mn oxides (MnOx) inhibited the conversion of free iodine (HOI/OI−) to iodate, resulting in the generation of more I-THMs. This study provides new insights into the DBP risks caused by Mn in DWDS.

Reducing ground and airborne drift losses in young apple orchards with PWM-controlled spray systems

Pulse Width Modulated (PWM) solenoid valves can be used to control nozzle flow rates for precision spray applications to reduce pesticide use, thereby reducing environmental risk and production cost. Field tests in a two-year-old young apple orchard were conducted to investigate spray losses to the ground and in the air for an air-blast sprayer equipped with three spray systems: 1) manually controlled constant-rate system enabled with the PWM spray system (Manual-PWM), 2) laser-guided variable-rate system enabled with the PWM spray system (Laser-PWM); and 3) conventional constant-rate system with disabled PWM valves (Disabled-PWM). Artificial targets (plastic plates and water sensitive papers) were placed under twelve trees randomly selected from four rows of the orchard to collect spray losses to the ground. Airborne spray losses were determined by using nylon screens, mounted at five heights on each of seven poles distributed at different distances from the first sprayed row. Laser-PWM and Manual-PWM produced significantly lower airborne and ground spray drift losses inside and outside the orchard than Disabled-PWM, and these losses decreased significantly as the distance away from the first sprayed row increased. Laser-PWM reduced the total airborne drift by 90.3% and total ground loss by 85.0% compared to Disabled-PWM whereas Manual-PWM decreased the same airborne and ground drift by 84.1% and 7.9%, respectively. Disabled-PWM produced detectable airborne losses that reached 88.4 m away from where the sprayer was operated. Thus, the air-blast orchard sprayer equipped with PWM solenoid valves controlled by either the automatic laser-guided system or manual system would have great potentials to improve pesticide application efficiency with significant reductions in both pesticide consumption in young apple orchards, and off-target drift loss to the environment.

Using a geophone as an actuator to estimate the velocity of leak noise propagation in buried water pipes

A common way to pinpoint a leak in a buried plastic water pipe is to use a leak noise correlator. This is performed by using the time delay between two measured signals and the velocity at which such signals travel along the pipe. In this paper, an investigation is carried out into the use of a geophone in reverse, driven by an oscillating voltage. It then acts as a tapping device, exciting the wave responsible for leak noise propagation, when it is attached to an access point to estimate leak noise velocity. Two different ways of exciting the geophone were investigated. Initial tests were conducted in the laboratory to determine the effectiveness of the device in generating a force over a wide frequency range. Field tests were then carried out on a buried pipe test rig and the predominantly fluid-borne wave was generated by the tapping device, that travelled at least 7 m.

Bacteria and Chemicals in My Bottled Water?!

As sale of bottled water has grown worldwide, the reuse of plastic bottles has also increased. Reusing plastic bottles is necessary to reduce plastic pollution. However, there are chemicals in the plastic that may end up in the bottled water. It is also possible to find bacteria in bottled water! These are only two of the problems plastic bottles can cause! They are also dangerous for the environment. If you want to better understand the issues with plastic water bottles and how to help prevent them, keep reading!

Aerosol transmission of human pathogens: From miasmata to modern viral pandemics and their preservation potential in the Anthropocene record

Ongoing uncertainty over the relative importance of aerosol transmission of COVID-19 is in part rooted in the history of medical science and our understanding of how epidemic diseases can spread through human populations. Ancient Greek medical theory held that such illnesses are transmitted by airborne pathogenic emanations containing particulate matter (“miasmata”). Notable Roman and medieval scholars such as Varro, Ibn al-Khatib and Fracastoro developed these ideas, combining them with early germ theory and the concept of contagion. A widely held but vaguely defined belief in toxic miasmatic mists as a dominant causative agent in disease propagation was overtaken by the science of 19th century microbiology and epidemiology, especially in the study of cholera, which was proven to be mainly transmitted by contaminated water. Airborne disease transmission came to be viewed as burdened by a dubious historical reputation and difficult to demonstrate convincingly. A breakthrough came with the classic mid-20th century work of Wells, Riley and Mills who proved how expiratory aerosols (their “droplet nuclei”) could transport still-infectious tuberculosis bacteria through ventilation systems. The topic of aerosol transmission of pathogenic respiratory diseases assumed a new dimension with the mid-late 20th century “Great Acceleration” of an increasingly hypermobile human population repeatedly infected by different strains of zoonotic viruses, and has taken centre stage this century in response to outbreaks of new respiratory infections that include coronaviruses. From a geoscience perspective, the consequences of pandemic-status diseases such as COVID-19, produced by viral pathogens utilising aerosols to infect a human population currently approaching 8 billion, are far-reaching and unprecedented. The obvious and sudden impacts on for example waste plastic production, water and air quality and atmospheric chemistry are accelerating human awareness of current environmental challenges. As such, the “anthropause” lockdown enforced by COVID-19 may come to be seen as a harbinger of change great enough to be preserved in the Anthropocene stratal record.

Technical evaluation of a prototype ratio 29:1 grid for adult patient cardiovascular angiography imaging conditions

The purpose of this work was to assess technical performance of a prototype high-ratio (r29), 80 line cm−1 grid for imaging conditions which mimic those for adult cardiovascular angiography. The standard equipment r15, 80 line cm−1 grid was used as a reference. Plastic Water® LR phantoms with thickness in the range 20–44 cm were used to simulate adult patient attenuation and scatter. Grids were tested using x-ray field of view 20 and 25 cm and x-ray source to detector distance (SID) 107 and 120 cm. The primary transmission fraction (TP ) was measured using both narrow beam geometry and a lead beam stop (BS) technique. Scatter transmission (TS ) was measured with the lead BS technique. The quantum signal to noise ratio improvement factor (K SNR) was used to describe relative grid performance. The experimental conditions required revised theory to assess grid performance. Theory to account for the detector glare and underestimation of scatter intensity by the lead BS method was developed. Also, novel K SNR theory was developed to allow direct comparison of two grids operated at different SID. Mean TP was modestly lower for the r29 versus r15 grid (0.69 versus 0.75). When tested under equivalent scatter condition, TS of the r29 grid was approximately ½ that of the r15 grid (0.18 versus 0.34). K SNR of the r29 grid at SID 120 cm compared to the r15 grid at SID 107 cm increased linearly with phantom thickness (range 1.0 to ∼1.16). Findings of this work indicate that the r29 grid used at SID 120 cm is expected to provide improved image quality (or reduced patient radiation dose) when compared to the r15 grid used at SID 107 cm for adult cardiovascular patients and that the potential benefit of the r29 grid increases with patient thickness >20 cm.

Measures to Cope with the Impact of Climate Change and Drought in the Island Region: A Study of the Water Literacy Awareness, Attitude, and Behavior of the Taiwanese Public

This study assessed people’s water literacy awareness, attitudes, and behaviors to iden-tify strategies for coping with drought and water scarcity. The data from 653 questionnaires were analyzed by statistical validation and using IBM SPSS 22 and IBM AMOS 26.0. The views of students, housewives, swimming pool owners, schoolteachers, and experts were collected and finally examined by multivariate validation analysis. People have a high level of water literacy and developed sufficient water-saving habits (4.60). Although most people believe that tap water is of good quality, it is difficult to deliver and expensive, and cannot be consumed directly. Even though people are aware of the water shortage crisis, willing to carry water bottles instead of using plastic bottled water, choosing to buy environmentally friendly cleaning products (4.08), performing water conservation behaviors on the go, taking showers within 6–15 min, and taking the initiative to notify the relevant authorities to repair water facilities, the frequency of using bottled water is still high due to work and living habits, consumption ability, and mobility constraints (34.6), and they are less willing to buy products with the “water proficiency label” (4.08) and participate in stream-cleaning activities (3.57). The willingness to participate in water purification activities is low. The public also feels that the government is responsible for solving the current water shortage crisis (3.71). There are significant differences in the perceptions, attitudes, and behaviors of water literacy among people of different genders, ages, and regions, depending on their work and consumption abilities, quality of life, and convenience (p < 0.05). Increasing water responsibility can enhance environmental management actions, consumer economic actions, and civic actions, while enhancing water perceptions and crisis awareness can further strengthen civic behaviors.

Uncovering the release of micro/nanoplastics from disposable face masks at times of COVID-19

Wearing face masks is a fundamental prevention and control measure to limit the spread of COVID-19. The universal use and improper disposal of single-use face masks are raising serious concerns for their environmental impact, owing to the foregone contribution to plastic water pollution during and beyond the pandemic. This study aims to uncover the release of micro/nanoplastics generated from face mask nonwoven textiles once discarded in the aquatic environment. As assessed by microscopy and flow cytometry, the exposure to different levels of mechanical stress forces (from low to high shear stress intensities) was proved effective in breaking and fragmenting face mask fabrics into smaller debris, including macro-, micro-, and nano-plastics. Even at the low level of fabric deterioration following the first second of treatment, a single mask could release in water thousands of microplastic fibers and up to 108 submicrometric particles, mostly comprised in the nano-sized domain. By contributing to the current lack of knowledge regarding the potential environmental hazards posed by universal face masking, we provided novel quantitative data, through a suitable technological approach, on the release of micro/nanoplastics from single-use face masks that can threaten the aquatic ecosystems to which they finally end-up.

Determination of bisphenol-A in plastic bottled water in markets of Zanjan, Iran

Determination of bisphenol-A in plastic bottled water in markets of Zanjan, Iran

Comparison between pressuremeter modulus (EPMT) and shear wave velocity (Vs) in silty clay soil

Pressuremeter Test (PMT) and shear wave velocity (Vs) are two important in-situ tests for determining soil deformation characteristics in different strain levels. The PMT is an expensive and time-consuming test that can measure pressuremeter modulus (EPMT) of soil and rock. The Vs is a low-cost test for determining soil deformation through the seismic method. So finding the relationship between PMT and Vs can be useful and cost-saving for cross-checking the parameters obtained by these two methods.In this study, 94 PMT and Vs tests were carried out on silty clay and clay soil from 3 sites in Iran, and the relationship between EPMT and Vs was investigated using regression analysis. Finally, the best statistical model for relationships was proposed according to the highest value of adjusted R2 and Fisher coefficient (F) and a minimum value of significance (Sig.). The results showed that there is a direct relationship between EPMT, Vs, and N60 with depth then the soils with higher relative density are at the deeper layers. On the other hand, there is a linear significant relationship between EPMT and Vs for each site with R2 > 0.79. When the data for all three sites are considered together, R2 decreased to 0.62 but the overall trend of the data is similar. Due to the similarity of the soil of the three sites in terms of classification, minor differences in plasticity index and water content ranges in the three sites can be a reason to reduce the R2. The comparison between estimated EPMT based on proposed equations in the present study and measured EPMT shows that the normalized consistency ratio is generally close to zero (−0.09 < CR < 0.06) so the equations are valid and reliable.A comparison of the results of the present and a previous study showed that the change rates of EPMT and VS were similar so that the CR values are generally close to zero (−0.09 < CR < 0.09). The minor difference between the EPMT and Vs in each site in the present study and the previous research is due to the soil type and plasticity specifications.

Microparticles and microplastics released from daily use of plastic feeding and water bottles and plastic injectors: potential risks to infants and children in China.

Daily use of plastic feeding and water bottles occur widely in China, and they could be sources for release of microplastics (MPs), which threaten the health of Chinese infants and children during daily usage. In this work, we investigated the use of polycarbonate (PC) and polypropylene (PP) for making water bottles (WBs) and polyphenylene sulfone resins (PPSU) for making feeding bottles (FBs), and we found that feeding bottles and water bottles released microparticles in amounts ranging from 53 to 393 particles/mL during 100 opening/closing cycles. The good linear regressions for plots of microparticles released vs. abrasion distance (r2 = 0.811) indicated that thick-necked bottles release more microparticles than thin-necked bottles. The brands and types of bottles (plastic vs. glass) influence microparticle release, and this indicates that high-quality plastic and glass bottles release fewer microparticles and are good for the health of infants and children. In addition to calcium stearate and silicone additives, the identified MPs account for 7.5 to 42.1% of released microparticles with different polymer types, sizes (from 20 to 500 μm) and shapes (cubic, spherical and irregular shapes). Additionally, an average of 1.74 MPs were released from an injection with a single-use plastic injector. Nevertheless, a number of microparticles and nanosized plastics were observed with all samples, suggesting that the health risks of micro- and nanosized particles to humans, especially babies and children, and the environment should be considered seriously.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11356-021-14939-7.