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1.
ACS Nano ; 18(20): 12808-12819, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38717026

ABSTRACT

Considerable progress has already been made in sweat sensors based on electrochemical methods to realize real-time monitoring of biomarkers. However, realizing long-term monitoring of multiple targets at the atomic level remains extremely challenging, in terms of designing stable solid contact (SC) interfaces and fully integrating multiple modules for large-scale applications of sweat sensors. Herein, a fully integrated wristwatch was designed using mass-manufactured sensor arrays based on hierarchical multilayer-pore cross-linked N-doped porous carbon coated by reduced graphene oxide (NPCs@rGO-950) microspheres with high hydrophobicity as core SC, and highly selective monitoring simultaneously for K+, Na+, and Ca2+ ions in human sweat was achieved, exhibiting near-Nernst responses almost without forming an interfacial water layer. Combined with computed tomography, solid-solid interface potential diffusion simulation results reveal extremely low interface diffusion potential and high interface capacitance (598 µF), ensuring the excellent potential stability, reversibility, repeatability, and selectivity of sensor arrays. The developed highly integrated-multiplexed wristwatch with multiple modules, including SC, sensor array, microfluidic chip, signal transduction, signal processing, and data visualization, achieved reliable real-time monitoring for K+, Na+, and Ca2+ ion concentrations in sweat. Ingenious material design, scalable sensor fabrication, and electrical integration of multimodule wearables lay the foundation for developing reliable sweat-sensing systems for health monitoring.


Subject(s)
Sweat , Wearable Electronic Devices , Wrist , Sweat/chemistry , Time Factors , Electrolytes/analysis , Graphite/chemistry , Porosity , Carbon/chemistry , Cations/chemistry , Humans , Biological Monitoring/instrumentation
2.
JAMA Netw Open ; 4(8): e2122998, 2021 08 02.
Article in English | MEDLINE | ID: mdl-34459906

ABSTRACT

Importance: Immune checkpoint inhibitors can produce distinct toxic effects that require prompt recognition and timely management. Objective: To develop a technology-enabled, dynamically adaptive protocol that can provide the accurate information needed to inform specific remedies for immune toxic effects in patients treated with immune checkpoint inhibitors. Design, Setting, and Participants: An open-label cohort study was conducted at a single tertiary referral center from September 6, 2019, to September 3, 2020. The median follow-up duration was 63 (interquartile range, 35.5-122) days. Fifty patients with genitourinary cancers treated with immune checkpoint inhibitors were enrolled. Interventions: A fit-for-purpose electronic platform was developed to enable active patient and care team participation. A smartphone application downloaded onto patients' personal mobile devices prompted them to report their symptoms at least 3 times per week. The set of symptoms and associated queries were paired with alert thresholds for symptoms requiring clinical action. Main Outcomes and Measures: The primary end point of this interim analysis was feasibility, as measured by patient and care team adherence, and lack of increase in care team staffing. Operating characteristics were estimated for each symptom alert and used to dynamically adapt the alert thresholds to ensure sensitivity while reducing unnecessary alerts. Results: Of the 50 patients enrolled, 47 had at least 1 follow-up visit and were included in the analysis. Median age was 65 years (range, 37-86), 39 patients (83%) were men, and 39 patients (83%) had metastatic cancer, with the most common being urothelial cell carcinoma and renal cell carcinoma (22 [47%] patients each). After initial onboarding, no further care team training or additional care team staffing was required. Patients had a median study adherence rate of 74% (interquartile range, 60%-86%) and 73% of automated alerts were reviewed within 3 days by the clinic team. Symptoms with the highest positive predictive value for adverse events requiring acute intervention included dizziness (21%), nausea/vomiting (26%), and shortness of breath (14%). The symptoms most likely to result in unnecessary alerts were arthralgia and myalgia, fatigue, and cough. Conclusions and Relevance: The findings of this cohort study suggest an acceptable and fiscally sound method can be developed to create a dynamic learning system to detect and manage immune-related toxic effects.


Subject(s)
Biological Monitoring/methods , Immune Checkpoint Inhibitors/toxicity , Immune Checkpoint Inhibitors/therapeutic use , Mobile Applications , Patient Reported Outcome Measures , Toxicity Tests/methods , Urogenital Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Biological Monitoring/instrumentation , Cohort Studies , Female , Humans , Male , Middle Aged , Texas , Toxicity Tests/instrumentation
3.
Sensors (Basel) ; 21(4)2021 Feb 05.
Article in English | MEDLINE | ID: mdl-33562707

ABSTRACT

Porous polymer dielectric materials have been developed to increase the sensitivity of capacitive pressure sensors, so that they might expand capacitive sensor use, and promote the realization of the advantages of this class of sensor in further fields. However, their use has not been demonstrated in physiological monitoring applications such as respiration monitoring and body position detection during sleep; an area in need of unmet medical attention for conditions such as sleep apnea. Here, we develop and characterize a sensor comprised of a poly dimethylsiloxane (PDMS) sponge dielectric layer, and PDMS/carbon black (CB) blend electrode layers, with suitable compliance and sensitivity for integration in mattresses, pillows, and athletic shoe insoles. With relatively high pressure sensitivity (~0.1 kPa-1) and mechanical robustness, this sensor was able to fulfill a wide variety of roles, including athletic monitoring in an impact mechanics scenario, by recording heel pressure during running and walking, and physiological monitoring, by detecting head position and respiration of a subject lying on a pad and pillow. The sensor detected considerably greater relative signal changes than those reported in recent capacitive sensor studies for heel pressure, and for a comparably minimal, resistive sensor during respiration, in line with its enhanced sensitivity.


Subject(s)
Athletes , Sports , Wearable Electronic Devices , Biological Monitoring/instrumentation , Monitoring, Physiologic , Porosity , Pressure , Silicones
5.
Appl Nurs Res ; 52: 151246, 2020 04.
Article in English | MEDLINE | ID: mdl-32199520

ABSTRACT

Sleep disruptions are common in pregnancy and can have significant maternal and infant health consequences. Management of sleep using a personal health monitoring (PHM) device may be effective in promoting behavior change and contribute to improved pregnancy-related sleep. The purpose of this pilot, randomized controlled trial was to determine the feasibility of recruitment (i.e., recruiting a 20% minority sample, most successful recruitment methods), retention, adherence, and data collection methods with a sample of pregnant women (n = 24) at 24 weeks gestation for a 12-week intervention using a PHM device. Of 24 enrolled participants, 20 (83%) were retained through the 12-week intervention and the follow-up at 2-4 weeks postpartum. The majority of participants had a four-year education and identified as White. Ninety-one percent (n = 11) wore the device for at least ten weeks. Pregnant women may be willing engage in sleep intervention research and wear a PHM to self-monitor sleep during pregnancy. Future research should consider recruitment methods tailored to recruit diverse populations of pregnant women.


Subject(s)
Biological Monitoring/instrumentation , Biological Monitoring/methods , Pregnant Women , Sleep Wake Disorders/diagnosis , Adult , Feasibility Studies , Female , Humans , Pilot Projects , Pregnancy
6.
Toxins (Basel) ; 12(3)2020 03 18.
Article in English | MEDLINE | ID: mdl-32197491

ABSTRACT

A variety of mycotoxins from different sources frequently contaminate farm products, presenting a potential toxicological concern for animals and human. Mycotoxin exposure has been the focus of attention for governments around the world. To date, biomarkers are used to monitor mycotoxin exposure and promote new understanding of their role in chronic diseases. The goal of this research was to develop and validate a sensitive UHPLC-MS/MS method using isotopically-labeled internal standards suitable for accurate determination of 18 mycotoxin biomarkers, including fumonisins, ochratoxins, Alternaria and emerging Fusarium mycotoxins (fumonisin B1, B2, and B3, hydrolyzed fumonisin B1 and B2, ochratoxin A, B, and alpha, alternariol, alternariol monomethyl ether, altenuene, tentoxin, tenuazonic acid, beauvericin, enniatin A, A1, B, and B1) in human urine. After enzymatic digestion with ß-glucuronidase, human urine samples were cleaned up using HLB solid phase extraction cartridges prior to instrument analysis. The multi-mycotoxin and analyte-specific method was validated in-house, providing satisfactory results. The method provided good linearity in the tested concentration range (from LOQ up to 25-500 ng/mL for different analytes), with R2 from 0.997 to 0.999. The limits of quantitation varied from 0.0002 to 0.5 ng/mL for all analytes in urine. The recoveries for spiked samples were between 74.0% and 133%, with intra-day precision of 0.5%-8.7% and inter-day precision of 2.4%-13.4%. This method was applied to 60 urine samples collected from healthy volunteers in Beijing, and 10 biomarkers were found. At least one biomarker was found in all but one of the samples. The high sensitivity and accuracy of this method make it practical for human biomonitoring and mycotoxin exposure assessment.


Subject(s)
Biological Monitoring/methods , Dietary Exposure/analysis , Food Contamination/analysis , Mycotoxins/urine , Adolescent , Adult , Aged , Biological Monitoring/instrumentation , Biomarkers/urine , Child , Child, Preschool , China , Chromatography, High Pressure Liquid/methods , Female , Healthy Volunteers , Humans , Limit of Detection , Male , Middle Aged , Reproducibility of Results , Solid Phase Extraction , Tandem Mass Spectrometry/methods , Young Adult
7.
Biofouling ; 36(1): 73-85, 2020 01.
Article in English | MEDLINE | ID: mdl-31985280

ABSTRACT

A CUSUM chart method is presented as an alternative tool for continuous monitoring of an electromagnetic field-based (EMF) antifouling (AF) treatment of a heat exchanger cooled by seawater. During an initial experimental phase, biofilm growth was allowed in a heat exchanger formed of four tubes until sufficient growth had been established. In two of the tubes, continuous EMF treatment was then applied. The heat transfer resistance and heat duty (heat transfer per unit time) results showed that biofilm adhesion was reduced by the EMF treatment. EMF treatments resulted in a 35% improvement in the heat transfer resistance values. The proposed CUSUM chart method showed that the EMF treatment increased the useful life of the heat exchanger by ∼20 days. Thus, CUSUM charts proved to be an efficient tool for continuous monitoring of an AF treatment using data collected online and can also be used to reduce operation and maintenance costs.


Subject(s)
Biofilms/growth & development , Biofouling/prevention & control , Biological Monitoring/methods , Electromagnetic Fields , Hot Temperature , Seawater/microbiology , Biological Monitoring/instrumentation
8.
Biosensors (Basel) ; 11(1)2020 Dec 31.
Article in English | MEDLINE | ID: mdl-33396519

ABSTRACT

The United States Centers for Disease Control and Prevention considers saliva contact the lead transmission means of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the coronavirus disease 2019 (COVID-19). Saliva droplets or aerosols expelled by heavy breathing, talking, sneezing, and coughing may carry this virus. People in close distance may be exposed directly or indirectly to these droplets, especially those droplets that fall on surrounding surfaces and people may end up contracting COVID-19 after touching the mucosa tissue on their faces. It is of great interest to quickly and effectively detect the presence of SARS-CoV-2 in an environment, but the existing methods only work in laboratory settings, to the best of our knowledge. However, it may be possible to detect the presence of saliva in the environment and proceed with prevention measures. However, detecting saliva itself has not been documented in the literature. On the other hand, many sensors that detect different organic components in saliva to monitor a person's health and diagnose different diseases that range from diabetes to dental health have been proposed and they may be used to detect the presence of saliva. This paper surveys sensors that detect organic and inorganic components of human saliva. Humidity sensors are also considered in the detection of saliva because a large portion of saliva is water. Moreover, sensors that detect infectious viruses are also included as they may also be embedded into saliva sensors for a confirmation of the virus' presence. A classification of sensors by their working principle and the substance they detect is presented. This comparison lists their specifications, sample size, and sensitivity. Indications of which sensors are portable and suitable for field application are presented. This paper also discusses future research and challenges that must be resolved to realize practical saliva sensors. Such sensors may help minimize the spread of not only COVID-19 but also other infectious diseases.


Subject(s)
Biological Monitoring/instrumentation , COVID-19/prevention & control , SARS-CoV-2/isolation & purification , Saliva/chemistry , Saliva/virology , Biological Monitoring/methods , COVID-19/enzymology , COVID-19/etiology , COVID-19/immunology , Communicable Diseases/enzymology , Communicable Diseases/etiology , Communicable Diseases/immunology , Communicable Diseases/virology , Humans , Influenza A Virus, H1N1 Subtype/chemistry , Influenza A Virus, H1N1 Subtype/enzymology , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H1N1 Subtype/isolation & purification , SARS-CoV-2/chemistry , SARS-CoV-2/immunology , Saliva/enzymology , Saliva/immunology , Viruses/chemistry , Viruses/enzymology , Viruses/immunology , Viruses/isolation & purification
9.
Mil Med ; 185(Suppl 1): 396-403, 2020 01 07.
Article in English | MEDLINE | ID: mdl-31498403

ABSTRACT

INTRODUCTION: Service members are exposed to ambient airborne pollutants that have been linked to adverse health effects; however, capabilities to identify and characterize exposures across multi-domain operations are currently lacking. Occupational and environmental exposure monitoring is problematic because there is not a single simple solution, and current technological limitations suggest that simultaneous deployment of multiple devices may be the most effective near-term strategy. MATERIALS AND METHODS: A broad industry scan of wearable, handheld, or portable occupational and environmental exposure monitoring devices was conducted, and subject matter experts were interviewed about the state of the field. RESULTS: This survey identified limitations including the inability to detect multiple analytes or analyte classes, size and weight, and detection limits, but multiple implementation strategies could be employed to meet a variety of combat needs. Device types could be layered, or specific device types could be deployed in acute toxic exposure environments such as dense urban population centers or subterranean spaces. CONCLUSIONS: Evolving technologies and data management strategies may advance personal exposure monitoring in the future. These new devices and methods will likely supplant current technologies, while still using the programmatic and data framework established with early implementation of current commercial off the shelf devices.


Subject(s)
Biological Monitoring/instrumentation , Environmental Exposure/analysis , Occupational Exposure/analysis , Biological Monitoring/methods , Biological Monitoring/statistics & numerical data , Hazardous Substances/adverse effects , Hazardous Substances/analysis , Humans , Surveys and Questionnaires , Wearable Electronic Devices/trends
10.
Scand J Caring Sci ; 34(3): 648-657, 2020 Sep.
Article in English | MEDLINE | ID: mdl-31614031

ABSTRACT

BACKGROUND: The majority of people with dementia prefer to live independently and safely in their own home cared for by their family members. Much effort has been invested in the development of technology, such as sensor-based networks. Many challenges remain, in particular gaining more knowledge about their experiences and perceived benefits. This study aimed to explore experiences, needs and benefits with using sensor-based technology for safety and independence in the homes of people with dementia and their family members. METHODS: This study is part of the TECH@HOME project, aiming to evaluate the effects of sensor-based technology on independence among people with dementia and caregiver stress among their family members. This study applied an inductive, qualitative approach with semi-structured interviews of people with dementia (n = 9) and family members (n = 21). The participants were interviewed between June and September 2018 after using the technology for at least 6 months. The interviews were analysed with manifest content analysis. RESULTS: Our findings highlighted that technology was considered as a precaution and a safety measure that could provide a sense of having control of the everyday life of the person with dementia. Understanding and acceptance of the technology were as important, together with the reliability of the technology. Ethical dilemmas related to the monitoring of the person with dementia in the home were also raised. CONCLUSION: This study provides insights into how people with dementia and family members experience and benefit from using sensor-based technology in their own homes. The knowledge generated is essential for healthcare professionals and policymakers developing and implementing care and service systems including technology, as well as for the industry.


Subject(s)
Biological Monitoring/instrumentation , Biological Monitoring/methods , Caregivers/psychology , Family/psychology , Health Personnel/psychology , Patient Safety , Remote Sensing Technology , Adult , Aged , Aged, 80 and over , Attitude to Computers , Dementia , Female , Humans , Male , Middle Aged , Qualitative Research , Reproducibility of Results
11.
Horm Behav ; 118: 104639, 2020 02.
Article in English | MEDLINE | ID: mdl-31765658

ABSTRACT

Adult neuroplasticity in the song control system of seasonal songbirds is largely driven by photoperiod-induced increases in testosterone. Prior studies of the relationships between testosterone, song performance and neuroplasticity used invasive techniques, which prevent analyzing the dynamic changes over time and often focus on pre-defined regions-of-interest instead of examining the entire brain. Here, we combined (i) in vivo diffusion tensor imaging (DTI) to assess structural neuroplasticity with (ii) repeated monitoring of song and (iii) measures of plasma testosterone concentrations in thirteen female photosensitive starlings (Sturnus vulgaris) who received a testosterone implant for 3 weeks. We observed fast (days) and slower (weeks) effects of testosterone on song behavior and structural neuroplasticity and determined how these effects correlate on a within-subject level, which suggested separate contributions of the song motor and anterior forebrain pathways in the development of song performance. Specifically, the increase in testosterone correlated with a rapid increase of song rate and RA volume, and with changes in Area X microstructure. After implant removal, these variables rapidly reverted to baseline levels. In contrast, the more gradual improvement of song quality was positively correlated with the fractional anisotropy values (DTI metric sensitive to white matter changes) of the HVC-RA tract and of the lamina mesopallialis, which contains fibers connecting the song control nuclei. Thus, we confirmed many of the previously reported testosterone-induced effects, like the increase in song control nuclei volume, but identified for the first time a more global picture of the spatio-temporal changes in brain plasticity.


Subject(s)
Biological Monitoring/methods , Brain/drug effects , Neuronal Plasticity/drug effects , Starlings , Telemetry/methods , Testosterone/pharmacology , Vocalization, Animal/drug effects , Animals , Biological Monitoring/instrumentation , Brain/metabolism , Diffusion Tensor Imaging/instrumentation , Diffusion Tensor Imaging/methods , Female , Male , Online Systems , Photoperiod , Starlings/blood , Starlings/physiology , Telemetry/instrumentation , Testosterone/blood
12.
ACS Sens ; 4(10): 2566-2570, 2019 10 25.
Article in English | MEDLINE | ID: mdl-31576740

ABSTRACT

Biologging is a scientific endeavor that studies the environment and animals within it by outfitting the latter with sensors of their dynamics as they roam freely in their natural habitats. As wearable technologies advance for the monitoring of human health, it may be instructive to reflect on the successes and failures of biologging in field biology over the past few decades. Several lessons may be of value. Physiological sensors can "encode" for a wider number of states than the one explicitly targeted, although the limits of this are debatable. The combination of orthogonal sensors turns out to be critical to delivering a high value data set. Sensor fusion and engineering for longevity are also important for success. This Perspective highlights successful strategies for biologging that hold promise for human health monitoring.


Subject(s)
Biological Monitoring/statistics & numerical data , Interdisciplinary Research/statistics & numerical data , Wearable Electronic Devices , Wireless Technology , Animals , Biological Monitoring/instrumentation , Cell Phone , Humans , Internet of Things
13.
Med Pr ; 70(6): 669-673, 2019 Dec 03.
Article in English | MEDLINE | ID: mdl-31597982

ABSTRACT

BACKGROUND: The method of measuring doses based on the thermoluminescence phenomenon is not an absolute method. For this reason, to obtain correct results, it is necessary to calibrate detectors in the known radiation field. This paper presents a method for calibrating thermoluminescent detectors used in the measurement of personal dose equivalents (Hp(0.07)) obtained by nuclear medicine facility personnel when handling the 99mTc radionuclide. MATERIAL AND METHODS: The authors used self-developed high-sensitivity thermoluminescent detectors and a HF320C X-ray unit, as well as a rod phantom. Dosimeters were calibrated in accordance with the ISO 4037-3 standard. During the measurements a vial containing a 99mTc radionuclide with well-known activity was also used. The energy characteristics were supplemented by using a 137Cs source (irradiator 60Co/137Cs). RESULTS: The value of the calibration coefficient for 118 keV energy energy was (1.90±0.02)×10-5 mSv/imp. Taking into account the correction factor specified for of 140 keV energy at 0.962, the value of the calibration coefficient for 140 keV energy was determined as (1.83±0.02)×10-5 mSv/imp. CONCLUSIONS: Verification of the calibration coefficient determined for 140 keV energy carried out with a vial containing a 99mTc radionuclide confirmed the correctness of the procedure. Med Pr. 2019;70(6):669-73.


Subject(s)
Biological Monitoring/instrumentation , Biological Monitoring/methods , Calibration/standards , Gamma Rays/adverse effects , Luminescence , Nuclear Medicine/standards , Thermoluminescent Dosimetry/standards , Absorption, Radiation , Adult , Female , Humans , Male , Middle Aged , Occupational Exposure/adverse effects , Occupational Exposure/standards
14.
Methods Mol Biol ; 2031: 259-274, 2019.
Article in English | MEDLINE | ID: mdl-31473964

ABSTRACT

Human biomonitoring studies aim to identify potential exposures to environmental, occupational, or lifestyle toxicants in human populations and are commonly used by public health decision makers to predict disease risk. The Comet assay measures changes in genomic stability and is one of the most reliable biomarkers to indicate early biological effects and therefore accepted by various governmental regulatory agencies. The appeal of the Comet assay lies in its relative simplicity, rapidity, sensitivity, and economic efficiency. Furthermore, the assay is known for its broad versatility, as it can be applied to virtually any human cell and easily adapted in order to detect particular biomarkers of interest, such as DNA repair capacity or single and double-strand breaks. In a standard experiment, isolated single cells are first embedded in agarose, and then lysed in high-salt solutions in order to remove all cellular contents except the DNA attached to a nuclear scaffold. Subsequent electrophoresis results in accumulation of undamaged DNA sequences at the proximity of the nuclear scaffold, while damaged sequences migrate toward the anode. When visualized with fluorochromes, these migrated DNA fragments resemble a Comet tail and can be quantified for their intensity and shape according to internationally drafted guidelines.


Subject(s)
Biological Monitoring/methods , Comet Assay/methods , DNA Damage/drug effects , Biological Monitoring/instrumentation , Cells, Cultured , Comet Assay/instrumentation , Equipment Design , Humans , Lymphocytes/drug effects , Lymphocytes/metabolism , Male , Microscopy, Fluorescence/instrumentation , Microscopy, Fluorescence/methods , Mutagens/toxicity , Single-Cell Analysis/instrumentation , Single-Cell Analysis/methods , Spermatozoa/drug effects , Spermatozoa/metabolism , Staining and Labeling/instrumentation , Staining and Labeling/methods
15.
Environ Pollut ; 254(Pt B): 113082, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31472454

ABSTRACT

Growing production and consumption of pharmaceuticals is a global problem. Due to insufficient data on the concentration and distribution of pharmaceuticals in the marine environment, there are no appropriate legal regulations concerning their emission. In order to understand all aspects of the fate of pharmaceuticals in the marine environment and their effect on marine biota, it is necessary to find the most appropriate model organism for this purpose. This paper presents an overview of the ecotoxicological studies of pharmaceuticals, regarding the assessment of Mytilidae as suitable organisms for biomonitoring programs and toxicity tests. The use of mussels in the monitoring of pharmaceuticals allows the observation of changes in the concentration and distribution of these compounds. This in turn gives valuable information on the amount of pharmaceutical pollutants released into the environment in different areas. In this context, information necessary for the assessment of risks related to pharmaceuticals in the marine environment are provided based on what effective management procedures can be developed. However, the accumulation capacity of individual Mytilidae species, the bioavailability of pharmaceuticals and their biological effects should be further scrutinized.


Subject(s)
Ecotoxicology/methods , Mytilidae/drug effects , Water Pollutants, Chemical/toxicity , Animals , Biological Monitoring/instrumentation , Biological Monitoring/methods , Biota , Ecotoxicology/instrumentation , Models, Biological , Mytilidae/growth & development , Seawater/analysis , Water Pollutants, Chemical/analysis
16.
Environ Sci Pollut Res Int ; 26(29): 29896-29907, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31407267

ABSTRACT

To assess the two most toxicologically relevant species of As, namely arsenite (As(III)) and arsenate (As(V)), chromatographic separations often require two separate chromatographic columns to address the co-elution of arsenobetaine (AsB) with As(III). This issue is typically observed using conventional isocratic methods on anion exchange columns, increasing cost and analysis time. Here, we optimize the extraction of inorganic As from a lichen air biomonitor and develop an isocratic method for the chromatographic separation of five common As species on a PRP X-100 anion exchange column, resulting in the complete baseline separation of all species under study. This method was then applied to lichen biomonitors from an urban and rural site to demonstrate its use. In order of abundance, the various arsenic species in lichens from the urban site in South Africa were As(V) > As(III) > AsB > dimethylarsinic acid (DMA) > monomethylarsonic acid (MMA), and As(V) > AsB > As(III) > DMA > MMA for the rural site, where MMA was present in extremely low, non-quantifiable concentrations in lichens from both sites. Total concentrations of As were higher in samples from the urban site (6.43 ± 0.25 µg/g) than in those from the rural site (1.87 ± 0.05 µg/g), with an overall extraction efficiency of 19% and 40%, respectively. The optimized method utilized relatively inexpensive solvents and is therefore low-cost and eco-friendly in comparison with conventional chromatographic techniques. This is the first study which addresses the optimized extraction and characterization of As species in a South African lichen biomonitor of air pollution. Graphical abstract .


Subject(s)
Arsenates/analysis , Arsenicals/analysis , Arsenites/analysis , Biological Monitoring/methods , Lichens/chemistry , Biological Monitoring/instrumentation , Cacodylic Acid/analysis , Chromatography, High Pressure Liquid/methods , Mass Spectrometry/methods , South Africa , Urbanization
17.
Environ Int ; 132: 105104, 2019 11.
Article in English | MEDLINE | ID: mdl-31465955

ABSTRACT

Silicone wristbands are being increasingly used to assess human exposure to semi-volatile organic compounds (SVOCs). However, it is unclear what exposure pathways wristbands integrate. To test the hypothesis that wristbands integrate inhalation and dermal exposures, we measured 38 chemicals from four compound groups (PAHs, PBDEs, nBFRs, and OPEs) in silicone wristbands and brooches, active air samples (Occupational Safety and Health Administration Versatile Sampler or OVS cartridge), and hand wipes from 10 adults during a 72-hour period. Phenanthrene, BDE-47, 2­ethylhexyl 2,3,4,5­tetrabromobenzoate (EHTBB), tris[(2R)­1­chloro­2­propyl] phosphate (TCIPP), and tris(1,3­dichloro­2­propyl) phosphate (TDCIPP) were the predominant compounds in all four matrices. In a linear regression analysis, the compound levels in OVS were positively associated with those in wristbands and brooches for nBFRs and OPEs, but not for PAHs and PBDEs. The compound levels in wristbands were positively associated with those in hand wipes and brooches for all chemicals. The regressions between the levels in wristbands and OVS or brooches combined with the levels in hand wipes showed stronger, supporting the hypothesis that wristbands captured inhalation and dermal exposure pathways.


Subject(s)
Biological Monitoring/instrumentation , Environmental Pollutants/analysis , Inhalation Exposure/analysis , Organophosphorus Compounds/analysis , Silicones/chemistry , Volatile Organic Compounds/analysis , Adult , Biological Monitoring/methods , Female , Flame Retardants/analysis , Halogenated Diphenyl Ethers/analysis , Humans , Hydrocarbons, Brominated/analysis , Male , Middle Aged , Polycyclic Aromatic Hydrocarbons/analysis , Skin , Wrist , Young Adult
18.
Environ Sci Pollut Res Int ; 26(26): 27353-27361, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31325092

ABSTRACT

The objective of this study was to investigate whether δ13C values can be used to identify pollen specie in the atmosphere. A Burkard 7-day recording volumetric spore trap was used to collected pollens in the atmosphere in Tainan City, Taiwan, from January 2 to December 28, 2006, and a light microscope was used to identify the pollen species and concentrations. A Burkard cyclone sampler was used to collect particulate matter and an elemental analyzer with an isotope ratio mass spectrometer was used to analyze the δ13C values. Our data showed that the predominate pollen specie in the atmosphere was Broussonetia papyrifera pollen and that the annual average concentration was 27 grains/m3 (pollen season, 36; nonpollen season, 9 grains/m3). The average δ13C value was - 26.19‰ for particulate matter in the atmosphere (pollen season, - 26.00‰; nonpollen season, - 26.28‰). No significant association was observed between δ13C values and Broussonetia papyrifera pollen concentrations. However, the δ13C value in the atmosphere was associated with the levels of Broussonetia papyrifera pollen among the samples with a diameter of particulate matter smaller than 10 µm at a level lower than 40 µg/m3. In addition, the relative contribution of Broussonetia papyrifera pollen to the carbon in the atmosphere using a two end-member mixing models was found to be associated with the Broussonetia papyrifera pollen concentration. In summary, our study suggested that δ13C values can be applied in the assessment of Broussonetia papyrifera pollen specie under specific conditions in the atmosphere.


Subject(s)
Air Pollutants/analysis , Air/analysis , Broussonetia/chemistry , Carbon Isotopes/analysis , Pollen/chemistry , Biological Monitoring/instrumentation , Biological Monitoring/methods , Particulate Matter/analysis , Seasons , Taiwan
19.
Article in English | MEDLINE | ID: mdl-31200442

ABSTRACT

BACKGROUND AND OBJECTIVES: With the spread of Wifi networks, safety concerns have arisen, with complaints of somatic disorders, notably in traditional libraries and media libraries. The aim of the present study was to describe the conditions and levels of exposure to radiofrequency electromagnetic fields in the real-life occupational conditions of those working in traditional libraries and media libraries. METHODS: Dynamic measurements, using an exposimeter, were taken in 20 radiofrequency bands from 88 to 5850 MHz. The activity of 28 library workers was analyzed on a space-time budget. An audit of exposure sources and static measurements enabled the work-places to be mapped. RESULTS: In seven libraries, 78,858 samples were taken over the 20 radiofrequency bands from 88 to 5850 MHz. Exposure was described for 28 working days. The median total field was 0.071 V/m (10th percentile: 0.022 V/m, 90th percentile: 0.534 V/m) and for Wifi the median field was 0.005 V/m (10th percentile: 0.005 V/m, 90th percentile: 0.028 V/m). Median individual exposure to Wifi frequency waves ranged from 0.005 to 0.040 V/m. CONCLUSIONS: Overall, the occupational exposure in this sector was close to the exposure in the general population. Peaks were due to the use of walkie-talkies by security staff. Exposure due to external sources depended on geographic location. Exposure in this occupation is well below the general occupational exposure levels, notably as regards Wifi.


Subject(s)
Biological Monitoring/instrumentation , Electromagnetic Fields , Libraries , Occupational Exposure/analysis , Radio Waves , Calibration , Cell Phone , Communications Media , Humans , Workplace
20.
JMIR Mhealth Uhealth ; 7(3): e11490, 2019 03 27.
Article in English | MEDLINE | ID: mdl-30916657

ABSTRACT

BACKGROUND: Temporal aspects of eating are an integral part of healthy eating, and regular eating has been associated with good diet quality and more successful weight control. Unfortunately, irregular eating is becoming more common. Self-monitoring of behavior has been found to be an efficient behavioral change technique, but the solution should be simple enough to ensure long-lasting adherence. OBJECTIVE: This study aimed to explore the influence of self-monitoring of daily eating pattern with mobile phone app on eating rhythm, eating behavior tendencies, and the underlying motives and attitudes related to eating. METHODS: A mobile phone app, Button, was developed for effortless self-monitoring of eating rhythm. The feasibility of the app was tested in a 30-day intervention. The participants (N=74) recorded their eating occasions during the intervention by pressing a button in the app widget. RESULTS: The average interval between meals increased (96 [SD 24] min during the first 10 days vs 109.1[SD 36.4] during the last 10 days) and the number of daily eating occasions decreased (4.9 [SD 0.9] during the first 10 days vs 4.4 [SD 0.9] during the last 10 days). The tendencies for cognitive restraint, emotional eating, and uncontrolled eating increased. Eating-related attitudes and motives remained largely unchanged. CONCLUSIONS: These results indicate that a simple self-monitoring tool is able to draw a user's attention to eating and is a potential tool to aid people to change their eating rhythm.


Subject(s)
Biological Monitoring/instrumentation , Feeding Behavior/psychology , Mobile Applications/standards , Time Factors , Adult , Biological Monitoring/methods , Biological Monitoring/standards , Cell Phone/instrumentation , Cell Phone/standards , Cell Phone/trends , Female , Humans , Male , Middle Aged , Mobile Applications/trends
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