Research on the health status and influencing factors of the older adult floating population in Shanghai.

Introduction: Over the past decade, against the dual background of population aging and mobility, the older adult/adults floating population has become a new type of mobile group in China, continually congregating in large cities, posing significant challenges to the socio-economic development, eldercare services, and public management of these metropolises. Shanghai, as a mega-city and the economic center of the China, is typically representative of the national population. Methods: Based on the dynamic monitoring data of Shanghai's floating population in 2018, this research uses mathematical statistics and binary Logistic regression models. Objective: This research analyzes the demographic characteristics and health status of the older adult/adults floating population in Shanghai in the new era and reveals its primary influencing factors. Results and discussion: (1) A prominent contradiction in the scale and structure of the older adult/adults floating population, with widowed and low-educated mobile older adult/adults requiring attention. (2) There is a lack of health knowledge, and the proportion of local reimbursement is low. Over 90% of migrant older adult/adults self-assessed their health (with a very few unable to care for themselves), far higher than the proportion of older adult/adults who are not sick (injured) or uncomfortable (actually healthy), which exceeds 70%. The health status of migrant older adult/adults deteriorates with age, and those who have never attended school and live alone have the worst health status. (3) Older adult/adults people with advanced age and low educational levels are at risk of health issues, while a better living environment can reduce the risk of illness in the older adult/adults floating population. Low family income, poor housing affordability, and the medical burden brought about by illness can easily lead to older adult/adults floating populations falling into the trap of older adult/adults poverty, and older adult/adults people from central regions and those who migrate along have difficulty adapting to city life, leading to poor self-assessed health. Meanwhile, community/enterprise health education helps to enhance the health protection awareness of the older adult/adults floating population. Finally, based on the governance concept of "mobility publicness," several public management and service optimization strategies for social support for the older adult/adults floating population in Shanghai are proposed.

Characterization of Wildland Firefighters' Exposure to Coarse, Fine, and Ultrafine Particles; Polycyclic Aromatic Hydrocarbons; and Metal(loid)s, and Estimation of Associated Health Risks.

Firefighters' occupational activity causes cancer, and the characterization of exposure during firefighting activities remains limited. This work characterizes, for the first time, firefighters' exposure to (coarse/fine/ultrafine) particulate matter (PM) bound polycyclic aromatic hydrocarbons (PAHs) and metal(loid)s during prescribed fires, Fire 1 and Fire 2 (210 min). An impactor collected 14 PM fractions, the PM levels were determined by gravimetry, and the PM-bound PAHs and metal(loid)s were determined by chromatographic and spectroscopic methodologies, respectively. Firefighters were exposed to a total PM level of 1408.3 and 342.5 µg/m3 in Fire 1 and Fire 2, respectively; fine/ultrafine PM represented more than 90% of total PM. Total PM-bound PAHs (3260.2 ng/m3 in Fire 1; 412.1 ng/m3 in Fire 2) and metal(loid)s (660.8 ng/m3 versus 262.2 ng/m3), distributed between fine/ultrafine PM, contained 4.57-24.5% and 11.7-12.6% of (possible/probable) carcinogenic PAHs and metal(loid)s, respectively. Firefighters' exposure to PM, PAHs, and metal(loid)s were below available occupational limits. The estimated carcinogenic risks associated with the inhalation of PM-bound PAHs (3.78 × 10-9 - 1.74 × 10-6) and metal(loid)s (1.50 × 10-2 - 2.37 × 10-2) were, respectively, below and 150-237 times higher than the acceptable risk level defined by the USEPA during 210 min of firefighting activity and assuming a 40-year career as a firefighter. Additional studies need to (1) explore exposure to (coarse/fine/ultrafine) PM, (2) assess health risks, (3) identify intervention needs, and (4) support regulatory agencies recommending mitigation procedures to reduce the impact of fire effluents on firefighters.

Phenotypic Characteristics and Occurrence Basis of Leaf Necrotic Spots in Response of Weedy Rice to Imazethapyr.

Weedy rice is the most challenging weed species to remove in rice production. We found a novel phenotype of seedling leaves which rapidly generates necrotic spots in response to imidazolinone herbicides in weedy rice, but its influencing factors and formation basis are still unknown. In this study, we used the leaf necrotic spot-producing type of weedy rice as the material. First, leaf necrotic spots were defined as physiological and vacuole-mediated cell necrosis by microscopic examination. The imazethapyr concentration was positively correlated with the degree of necrotic spots occurring, while the action site was in accordance with necrosis using herbicide stability tests combined with fluorescence parameters. Furthermore, transcriptome analysis revealed significant differences in the gene expression of endoplasmic reticulum stress and the lipid metabolism membrane structure damage pathway during necrosis, as confirmed by transmission electron microscopy. The light-temperature test also showed that high temperature and intense light could promote the appearance of necrotic spots. These experimental results are helpful in clarifying the process and basis of imazethapyr in inducing the rapid generation of necrotic spots in rice leaves and providing new insight into understanding the mechanism of response to imidazolinone herbicides and the control of weedy rice.

Comparison of ESIN and other minimally invasive techniques for anterior pelvic ring injury: a finite element analysis and case-control study.

OBJECT: A novel technique, percutaneous elastic stable intramedullary nail fixation (ESIN), proposed by our team for the treatment of anterior pelvic ring injury. Finite element analysis and retrospective case-control study were used to compare biomechanical properties and clinical outcomes between ESIN and other techniques. METHODS: Four groups of finite element models of pelvic anterior ring injury were simulated, including ESIN (model A), retrograde transpubic screw fixation (RTSF, model B), subcutaneous internal fixator (model C), and external fixator (model D), and a vertical downward load of 500 N was applied to the S1 vertebral endplate. Stress and displacement distributions of intact pelvis, displacement distributions of pubic fracture fragments, and stress distributions of fixation devices were analysed. Then 31 patients with anterior pelvic ring injury (15 in the ESIN group and 16 in the RTSF group) were reviewed. Clinical outcomes were evaluated at the final follow-up. Postoperative complications were also recorded. RESULTS: Under 500N loading, the intact stability of the pelvis was compared as follows: model B (20.58 mm, 121.82 MPa), model A (20.80 mm, 129.97 MPa), model C (22.02 mm, 141.70 MPa), and model D (22.57 mm, 147.06 MPa). The regional stability of superior pubic ramus was compared as follows: model B (9.48 mm), model A (10.16 mm), model C (10.52 mm), and model D (10.76 mm). All 31 patients received follow-up at least 12 months postsurgery (range 12-20 months). Age, sex, injury mechanism, fracture type, time between the injury and operation, American Society of Anesthesiologists score, intraoperative blood loss, hospital stay, follow-up period, time to union, and Majeed scores did not differ significantly between the two groups ( P >0.05). However, the differences in the duration of unilateral surgery, unilateral intraoperative fluoroscopy and one-time success rate were significant ( P <0.05). CONCLUSIONS: With sufficient biomechanical stability and minimally invasive advantage, the percutaneous technique using ESIN can be used to successfully treat anterior pelvic ring injuries. In addition, advantages over RTSF include a shorter duration of surgery, reduced requirement for intraoperative fluoroscopy, and a higher one-time success rate. ESIN therefore constitutes a good alternative to RTSF.

Blueprint for the design, construction, and validation of a plastic and phthalate-minimised laboratory.

Micro and nanosized plastics (MNPs), and a range of associated additive chemicals, have become pervasive contaminants that humans and the environment are exposed to everyday. However, one of the principal challenges in their analysis is adequate strategies to minimise background contamination. Here a blueprint for a specialised plastics and additive-minimised clean room laboratory built for this purpose is presented. Common laboratory construction materials (n = 23) were tested, including acoustic baffles, ceiling materials, floor materials, glazing rubber, and silicone sealant. The % polymer content ranged from 2-76% w/w while the sum concentration of six phthalates ranged from 0.81 (0.73-0.86) to 21000 (15000-27000) mg/kg, assigning many of these materials as inappropriate for use in a clean room environment. The final design of the laboratory consisted of three interconnected rooms, operated under positive pressure with the inner rooms constructed almost entirely of stainless steel. Background concentrations of MNPs and phthalates in the new laboratory were compared to two Physical Containment Level 2 (PC2) laboratory environments, with concentrations of MNPs reduced by > 100 times and phthalates reduced by up to 120 times. This study reports the first known clean room of its kind and provides a blueprint for reference and use by future plastics research.

Characteristics of Step-Shaped Laser-Driven Flyers on Fiber End Face Based on a Ti/Al Ablation Layer.

Laser-driven flyers (LDF), which can launch the flyer on the interaction of a laser pulse with a thin film of metal, have been widely used in many fields, such as ignition, space scrap metal science, and dynamic high-pressure physics. However, at present, further development of LDF is being hindered by the high reflectivity of the ablation layer and low energy utilization efficiency of LDF on the fiber end face. Herein, improved LDFs were designed and fabricated by mask plate and magnetron sputtering. Improved LDF incorporates a Ti/Al composite film as the ablation layer, while the flyer layer features a smaller diameter round platform design. Reflectivity of samples under static and dynamic conditions and driving characteristics of samples were tested using an optical isolator and photonic doppler velocimetry system. The velocity of the improved LDFs reaches 1.7 km/s with a peak acceleration of 8.7 × 1010 m/s2. LDF with a Ti/Al composite film as the ablation layer demonstrates a static absorption rate of 59%, which gradually increases to 65% under laser irradiation. This absorption rate is notably higher compared with the static absorption rate (20%) and the peak absorption rate under laser irradiation (40%) of an Al layer. Consequently, there is a substantial improvement of about 35% in the flyer velocity. In contrast to the plane-shaped LDF, the velocity profile of the flyer and impact crater morphology suggest that the step-shaped LDF offers a 15% improvement in velocity and a 50% increase in acceleration, with better flyer integrity observed.

Non-invasive differential diagnosis of teratomas from other intracranial germ cell tumours using MRI-based fractal and radiomic analyses.

OBJECTIVES: The histologic subtype of intracranial germ cell tumours (IGCTs) is an important factor in deciding the treatment strategy, especially for teratomas. In this study, we aimed to non-invasively diagnose teratomas based on fractal and radiomic features. MATERIALS AND METHODS: This retrospective study included 330 IGCT patients, including a discovery set (n = 296) and an independent validation set (n = 34). Fractal and radiomic features were extracted from T1-weighted, T2-weighted, and post-contrast T1-weighted images. Five classifiers, including logistic regression, random forests, support vector machines, K-nearest neighbours, and XGBoost, were compared for our task. Based on the optimal classifier, we compared the performance of clinical, fractal, and radiomic models and the model combining these features in predicting teratomas. RESULTS: Among the diagnostic models, the fractal and radiomic models performed better than the clinical model. The final model that combined all the features showed the best performance, with an area under the curve, precision, sensitivity, and specificity of 0.946 [95% confidence interval (CI): 0.882-0.994], 95.65% (95% CI: 88.64-100%), 88.00% (95% CI: 77.78-96.36%), and 91.67% (95% CI: 78.26-100%), respectively, in the test set of the discovery set, and 0.944 (95% CI: 0.855-1.000), 85.71% (95% CI: 68.18-100%), 94.74% (95% CI: 83.33-100%), and 80.00% (95% CI: 58.33-100%), respectively, in the independent validation set. SHapley Additive exPlanations indicated that two fractal features, two radiomic features, and age were the top five features highly associated with the presence of teratomas. CONCLUSION: The predictive model including image and clinical features could help guide treatment strategies for IGCTs. CLINICAL RELEVANCE STATEMENT: Our machine learning model including image and clinical features can non-invasively predict teratoma components, which could help guide treatment strategies for intracranial germ cell tumours (IGCT). KEY POINTS: • Fractals and radiomics can quantitatively evaluate imaging characteristics of intracranial germ cell tumours. • Model combing imaging and clinical features had the best predictive performance. • The diagnostic model could guide treatment strategies for intracranial germ cell tumours.

Calibration and Application of PUF Disk Passive Air Samplers To Assess Chlorinated Paraffins in Ambient Air in Australia, China, and Vietnam.

Ambient air samples were collected in Brisbane (Australia), Dalian (China), and Hanoi (Vietnam) during Mar 2013-Feb 2018 using polyurethane foam based passive air samplers. A sampling rate calibration experiment was conducted for chlorinated paraffins (CPs, i.e., short-chain, medium-chain, and long-chain CPs), where the sampling rates were 4.5 ± 0.7, 4.8 ± 0.3, and 4.8 ± 2.1 m3 day-1 for SCCPs, MCCPs, and LCCPs, respectively. The atmospheric concentration of CPs was then calculated and the medians of ∑CPs were 0.079, 1.0, and 0.89 ng m-3 in Brisbane, Dalian, and Hanoi, respectively. The concentration of CPs in Brisbane's air remained at low levels, with no significant differences observed between the city background site and the city center site, indicating limited usage and production of CPs in this city. The highest concentration of MCCPs was detected in Dalian, while the highest concentration of SCCPs was detected in Hanoi. A decrease of SCCP concentration and an increase of MCCPs' were found in Brisbane's air from 2016 to 2018, while increasing trends for both SCCPs and MCCPs were observed in Dalian. These results indicated impacts from different sources of CPs in the investigated cities.

Diffusion MRI is valuable in brainstem glioma genotyping with quantitative measurements of white matter tracts.

OBJECTIVES: To investigate the value of diffusion MRI (dMRI) in H3K27M genotyping of brainstem glioma (BSG). METHODS: A primary cohort of BSG patients with dMRI data (b = 0, 1000 and 2000 s/mm2) and H3K27M mutation information were included. A total of 13 diffusion tensor and kurtosis imaging (DTI; DKI) metrics were calculated, then 17 whole-tumor histogram features and 29 along-tract white matter (WM) microstructural measurements were extracted from each metric and assessed within genotypes. After feature selection through univariate analysis and the least absolute shrinkage and selection operator method, multivariate logistic regression was used to build dMRI-derived genotyping models based on retained tumor and WM features separately and jointly. Model performances were tested using ROC curves and compared by the DeLong approach. A nomogram incorporating the best-performing dMRI model and clinical variables was generated by multivariate logistic regression and validated in an independent cohort of 27 BSG patients. RESULTS: At total of 117 patients (80 H3K27M-mutant) were included in the primary cohort. In total, 29 tumor histogram features and 41 WM tract measurements were selected for subsequent genotyping model construction. Incorporating WM tract measurements significantly improved diagnostic performances (p < 0.05). The model incorporating tumor and WM features from both DKI and DTI metrics showed the best performance (AUC = 0.9311). The nomogram combining this dMRI model and clinical variables achieved AUCs of 0.9321 and 0.8951 in the primary and validation cohort respectively. CONCLUSIONS: dMRI is valuable in BSG genotyping. Tumor diffusion histogram features are useful in genotyping, and WM tract measurements are more valuable in improving genotyping performance. CLINICAL RELEVANCE STATEMENT: This study found that diffusion MRI is valuable in predicting H3K27M mutation in brainstem gliomas, which is helpful to realize the noninvasive detection of brainstem glioma genotypes and improve the diagnosis of brainstem glioma. KEY POINTS: • Diffusion MRI has significant value in brainstem glioma H3K27M genotyping, and models with satisfactory performances were built. • Whole-tumor diffusion histogram features are useful in H3K27M genotyping, and quantitative measurements of white matter tracts are valuable as they have the potential to improve model performance. • The model combining the most discriminative diffusion MRI model and clinical variables can help make clinical decision.

A Segmentation Framework With Unsupervised Learning-Based Label Mapper for the Ventricular Target of Intracranial Germ Cell Tumor.

Intracranial germ cell tumors are rare tumors that mainly affect children and adolescents. Radiotherapy is the cornerstone of interdisciplinary treatment methods. Radiation of the whole ventricle system and the local tumor can reduce the complications in the late stage of radiotherapy while ensuring the curative effect. However, manually delineating the ventricular system is labor-intensive and time-consuming for physicians. The diverse ventricle shape and the hydrocephalus-induced ventricle dilation increase the difficulty of automatic segmentation algorithms. Therefore, this study proposed a fully automatic segmentation framework. Firstly, we designed a novel unsupervised learning-based label mapper, which is used to handle the ventricle shape variations and obtain the preliminary segmentation result. Then, to boost the segmentation performance of the framework, we improved the region growth algorithm and combined the fully connected conditional random field to optimize the preliminary results from both regional and voxel scales. In the case of only one set of annotated data is required, the average time cost is 153.01 s, and the average target segmentation accuracy can reach 84.69%. Furthermore, we verified the algorithm in practical clinical applications. The results demonstrate that our proposed method is beneficial for physicians to delineate radiotherapy targets, which is feasible and clinically practical, and may fill the gap of automatic delineation methods for the ventricular target of intracranial germ celltumors.

Evaluation and identification of chemical migrants leached from baby food pouch packaging.

Multilayer plastic pouch (MLPP) has an estimated 9% annual increase of market growth. However, the migrants it can introduce to food has not yet been systematically studied. A total of 79 MLPPs for baby food were purchased from major retail outlets in Australia. The methodology for testing chemical migration followed the design of previous studies using four types of selected simulants according to the European Committee Regulation No. 10/2011 method. Four bisphenols and five phthalic acid diesters (PAEs) were detected, including the ones known for endocrine disrupting effect in human. Three intentionally added and 23 non-intentionally added substances (NIAS) were tentatively identified through a suspect screening procedure. Out of the 23 NIAS, neopentyl glycol - phthalic acid - 1,6-hexanediol - phthalic acid oligomer was identified for the first time with MLPP. A further two NIAS were detected for the first time in baby food related products. For 40% of the pouches where adipic acid - diethylene glycol was detected, the estimated exposure from consuming one pouch of food per day may exceed the threshold of toxicological concern established based on the Cramer classification.

Diffusion MRI-based connectomics features improve the noninvasive prediction of H3K27M mutation in brainstem gliomas.

PURPOSE: To establish an individualized predictive model to identify patients with brainstem gliomas (BSGs) at high risk of H3K27M mutation, with the inclusion of brain structural connectivity analysis based on diffusion MRI (dMRI). MATERIALS AND METHODS: A primary cohort of 133 patients with BSGs (80 H3K27M-mutant) were retrospectively included. All patients underwent preoperative conventional MRI and dMRI. Tumor radiomics features were extracted from conventional MRI, while two kinds of global connectomics features were extracted from dMRI. A machine learning-based individualized H3K27M mutation prediction model combining radiomics and connectomics features was generated with a nested cross validation strategy. Relief algorithm and SVM method were used in each outer LOOCV loop to select the most robust and discriminative features. Additionally, two predictive signatures were established using the LASSO method, and simplified logistic models were built using multivariable logistic regression analysis. An independent cohort of 27 patients was used to validate the best model. RESULTS: 35 tumor-related radiomics features, 51 topological properties of brain structural connectivity networks, and 11 microstructural measures along white matter tracts were selected to construct a machine learning-based H3K27M mutation prediction model, which achieved an AUC of 0.9136 in the independent validation set. Radiomics- and connectomics-based signatures were generated and simplified combined logistic model was built, upon which derived nomograph achieved an AUC of 0.8827 in the validation cohort. CONCLUSION: dMRI is valuable in predicting H3K27M mutation in BSGs, and connectomics analysis is a promising approach. Combining multiple MRI sequences and clinical features, the established models have good performance.

An Exploratory Analysis of Firefighter Reproduction through Survey Data and Biomonitoring.

Firefighters are occupationally exposed to chemicals that may affect fertility. To investigate this effect, firefighters were recruited to contribute blood, urine, breast milk or semen samples to (1) evaluate chemical concentrations and semen parameters against fertility standards and the general population; (2) assess correlations between chemical concentrations and demographics, fire exposure and reproductive history; and (3) consider how occupational exposures may affect reproduction. A total of 774 firefighters completed the online survey, and 97 firefighters produced 125 urine samples, 113 plasma samples, 46 breast milk samples and 23 semen samples. Blood, urine and breast milk samples were analysed for chemical concentrations (semivolatile organic compounds, volatile organic compounds, metals). Semen samples were analysed for quality (volume, count, motility, morphology). Firefighter semen parameters were below WHO reference values across multiple parameters. Self-reported rates of miscarriage were higher than the general population (22% vs. 12-15%) and in line with prior firefighter studies. Estimated daily intake for infants was above reference values for multiple chemicals in breast milk. More frequent fire incident exposure (more than once per fortnight), longer duration of employment (≥15 years) or not always using a breathing apparatus demonstrated significantly higher concentrations across a range of investigated chemicals. Findings of this study warrant further research surrounding the risk occupational exposure has on reproduction.

There's something in the air: A review of sources, prevalence and behaviour of microplastics in the atmosphere.

Literature regarding microplastics in the atmosphere has advanced in recent years. However, studies have been undertaken in isolation with minimal collaboration and exploration of the relationships between air, deposition and dust. This review collates concentrations (particle count and mass-based), shape, size and polymetric characteristics for microplastics in ambient air (m3), deposition (m2/day), dust (microplastics/g) and snow (microplastics/L) from 124 peer-reviewed articles to provide a holistic overview and analysis of our current knowledge. In summary, ambient air featured concentrations between <1 to >1000 microplastics/m3 (outdoor) and <1 microplastic/m3 to 1583 ± 1181 (mean) microplastics/m3 (indoor), consisting of polyethylene terephthalate, polyethylene, polypropylene. No difference (p > 0.05) was observed between indoor and outdoor concentrations or the minimum size of microplastics (p > 0.5). Maximum microplastic sizes were larger indoors (p < 0.05). Deposition concentrations ranged between 0.5 and 1357 microplastics/m2/day (outdoor) and 475 to 19,600 microplastics/m2/day (indoor), including polyethylene, polystyrene, polypropylene, polyethylene terephthalate. Concentrations varied between indoor and outdoor deposition (p < 0.05), being more abundant indoors, potentially closer to sources/sinks. No difference was observed between the minimum or maximum reported microplastic sizes within indoor and outdoor deposition (p > 0.05). Road dust concentrations varied between 2 ± 2 and 477 microplastics/g (mean), consisting of polyvinyl chloride, polyethylene, polypropylene. Mean outdoor dust concentrations ranged from <1 microplastic/g (remote desert) to between 18 and 225 microplastics/g, comprised of polyethylene terephthalate, polyamide, polypropylene. Snow concentrations varied between 0.1 and 30,000 microplastics/L, containing polyethylene, polyamide, polypropylene. Concentrations within indoor dust varied between 10 and 67,000 microplastics/g, including polyethylene terephthalate, polyethylene, polypropylene. No difference was observed between indoor and outdoor concentrations (microplastics/g) or maximum size (p > 0.05). The minimum size of microplastics were smaller within outdoor dust (p > 0.05). Although comparability is hindered by differing sampling methods, analytical techniques, polymers investigated, spectral libraries and inconsistent terminology, this review provides a synopsis of knowledge to date regarding atmospheric microplastics.

Ferroptosis participated in hippocampal neuroinflammation damage of in offspring rats after maternal sleep deprivation.

Sleep deprivation during pregnancy has important effects on the pregnant woman herself and her offspring, and some studies have found that neuroinflammation in her offspring is important, but the mechanisms are poorly understood. To investigate the involvement of ferroptosis in cognitive impairment due to hippocampal neuroinflammation in offspring rats after maternal sleep deprivation. SD rats exposed to late gestational sleep deprivation were deprived of sleep for 72 h. Their offspring were given the ferroptosis inhibitor liproxstatin-1 (5 mg/kg) intraperitoneally 3 days after birth. The results showed that MSD resulted in impaired learning memory capacity and significant downregulation of PSD95 and NeuN. Microglia were significantly activated, inflammatory factor expression was increased, the ferroptosis regulatory protein GPX4 was downregulated, ACSL4 was significantly upregulated, and lipid metabolite 4-HNE expression was increased. In contrast, the MSD-induced impairment of inflammation and learning memory capacity in the offspring was ameliorated after treatment with ferroptosis inhibitors. These results suggest that MSD-induced neural damage characterized ferroptosis in the hippocampal region of the offspring rats, leading to a decrease in learning and memory function, which may be related to the decreased levels of Nrf2 and HO-1.

Detections of organophosphate and pyrethroid insecticide metabolites in urine and sweat obtained from women during infrared sauna and exercise: A pilot crossover study.

Synthetic pesticides such as organophosphates and pyrethroids are commonly used worldwide yet the metabolic and long-term human health effects of these environmental exposures are unclear. Urinary detections of metabolites involving both classes of insecticides have been documented in various global populations. However, reports documenting similar detections in human sweat are sparse. In this study, the concentrations of four insecticide metabolites were measured using liquid chromatography coupled with tandem mass spectrometry in repeated sweat and urine collections (n = 85) from 10 women undergoing three interventions (control, infrared sauna and indoor bicycling) within a single-blinded randomised crossover trial. The Friedman test with post-hoc two-way analysis of variance, the related-samples Wilcoxon signed rank test and the Spearman's rank-order correlation test were used to analyse the results. Organophosphate metabolites were detected in 84.6% (22/26) and pyrethroids in 26.9% (7/26) of the collected sweat samples (pooled per individual, per intervention). Urinary concentrations of three of the four metabolites marginally increased after infrared sauna bathing: 3,5,6-trichloro-2-pyridinol (z = 2.395, p = 0.017); 3-phenoxybenzoic acid (z = 2.599, p = 0.009); and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (z = 2.090, p = 0.037). Urinary 3-phenoxybenzoic acid also increased after exercise (z = 2.073, p = 0.038) and demonstrated the most temporal variability (days to weeks) of any of the urinary metabolites. Definitive sweat/urine correlations were not demonstrated. These results indicate metabolites from organophosphate and pyrethroid pesticides can be detected in human sweat and this raises intriguing questions about perspiration and its role in the metabolism and excretion of synthetic pesticides.

Exposure to PAHs during Firefighting Activities: A Review on Skin Levels, In Vitro/In Vivo Bioavailability, and Health Risks.

Occupational exposure as a firefighter is a complex activity that continuously exposes subjects to several health hazards including fire emissions during firefighting. Firefighters are exposed to polycyclic aromatic hydrocarbons (PAHs), known as toxic, mutagenic, and carcinogenic compounds, by inhalation, dermal contact, and ingestion. In this work, a literature overview of firefighters' dermal exposure to PAHs after firefighting and data retrieved from skin in vitro/in vivo studies related to their dermal absorption, bioavailability, and associated toxicological and carcinogenic effects are reviewed. The evidence demonstrates the contamination of firefighters' skin with PAHs, mainly on the neck (2.23-62.50 ng/cm2), wrists (0.37-8.30 ng/cm2), face (2.50-4.82 ng/cm2), and hands (1.59-4.69 ng/cm2). Concentrations of possible/probable carcinogens (0.82-33.69 ng/cm2), including benzopyrene isomers, were found on firefighters' skin. PAHs penetrate the skin tissues, even at low concentrations, by absorption and/or diffusion, and are locally metabolized and distributed by the blood route to other tissues/organs. Lighter PAHs presented increased dermal permeabilities and absorption rates than heavier compounds. Topical PAHs activate the aryl hydrocarbon receptor and promote the enzymatic generation of reactive intermediates that may cause protein and/or DNA adducts. Future research should include in vitro/in vivo assays to perform a more realistic health risk assessment and to explore the contribution of dermal exposure to PAHs total internal dose.

Semiquantitative Characterization of Bromo-chloro Paraffins and Olefins in the Australian Environment.

A semiquantitative high-resolution mass spectrometry method was developed and applied to assess the occurrence of bromo-/chloro paraffins (BCPs) and olefins (BCOs) in the environment. More than 400 possible BCPs and BCO congener groups were detected in dust, air, and sewage sludge samples collected from Australia. Median chain analytes with the number of halogen atoms <7 (CnHmClxBry, 14 ≤ n ≤ 17, x + y < 7) prevailed in the dust and sludge samples, while short chain analytes (CnHmClxBry, 10 ≤ n ≤ 13, x + y < 7) predominated the air samples. The estimated concentrations of ∑BCPs and ∑BCOs in dust and sludge were approximately 20% that of the chlorinated paraffins (CPs) present, with the median concentrations of 5.4 µg/g (dust) and 0.18 µg/g (sludge) for ∑BCPs and 22 µg/g (in dust) and 0.50 µg/g (sludge) for BCOs. In the air samples, the concentrations of BCPs (0.020 pg/m3) and BCOs (0.032 pg/m3) were 3-4 orders of magnitudes lower than the concentrations of CPs (790 pg/m3). Significant correlations (P < 0.001) were found between the concentration of CPs, BCPs, and BCOs in all the matrices.

Characterization of glyphosate and AMPA concentrations in the urine of Australian and New Zealand populations.

Glyphosate is the most used herbicide globally, but our understanding of human exposure and how different uses affect exposure is not well understood. The aim of this study was to obtain the first data on glyphosate and its primary degradation product aminomethylphosphonic acid (AMPA) concentrations in pooled and individual urine from the Australia and New Zealand region using a sensitive direct injection method and compare results with studies from elsewhere. Pooled urine samples from the Australian general population (n = 125 pools representing >1875 individuals) and individual urine samples (n = 27) from occupationally exposed New Zealand farmers were analysed by LC-MS/MS. Glyphosate was detected above the LOD (0.20-1.25 µg/L) in 8 % of the Australian population pooled urine samples with most detections in the 45-60 years age group. Furthermore, glyphosate (0.85 to 153 µg/L) and AMPA (0.50 to 3.35 µg/L) were detected in 96 % and 33 % of farmers, respectively. The maximum glyphosate urine concentration was 1.7 times above the recommended acceptable daily intake (ADI), when assuming a urinary excretion rate of 1 %. The pooled sampling and analysis approach proved effective for rapid large-scale screening of populations and could be used to determine where targeted and more specific individual sampling may be required.