Epidemiology and outcomes of brain trauma in rural and urban populations: a systematic review and meta-analysis.

OBJECTIVE: To identify and describe differences in demographics, injury characteristics, and outcomes between rural and urban patients suffering brain injury. DATA SOURCES: CINAHL, Emcare, MEDLINE, and Scopus. REVIEW METHODS: A systematic review and meta-analysis of studies comparing epidemiology and outcomes of rural and urban brain trauma was conducted in accordance with PRISMA and MOOSE guidelines. RESULTS: 36 studies with ~ 2.5-million patients were included. Incidence of brain injury was higher in males, regardless of location. Rates of transport-related brain injuries, particularly involving motorized vehicles other than cars, were significantly higher in rural populations (OR:3.63, 95% CI[1.58,8.35], p = 0.002), whereas urban residents had more fall-induced brain trauma (OR:0.73, 95% CI[0.66,0.81], p < 0.00001). Rural patients were 28% more likely to suffer severe injury, indicated by Glasgow Coma Scale (GCS)≤8 (OR:1.28, 95% CI[1.04,1.58], p = 0.02). There was no difference in mortality (OR:1.09, 95% CI[0.73,1.61], p = 0.067), however, urban patients were twice as likely to be discharged with a good outcome (OR:0.52, 95% CI[0.41,0.67], p < 0.00001). CONCLUSIONS: Rurality is associated with greater severity and poorer outcomes of traumatic brain injury. Transport accidents disproportionally affect those traveling on rural roads. Future research recommendations include addition of prehospital data, adequate follow-up, standardized measures, and sub-group analyses of high-risk groups, e.g. Indigenous populations.

Store-and-forward (asynchronous) doctor-to-dermatologist non-skin cancer specific teledermatology services in Australia: A scoping review.

Store-and-forward teledermatology (SAFT) has become increasingly popular as a means to increase access to specialist care and address healthcare disparities such as those experienced by rural communities. A contemporary systematic overview of the Australian SAFT services and outcomes for all dermatological conditions is missing. This scoping review provides an overview of Australian SAFT models. Twelve studies were identified through web databases, grey literature sites and reference lists of eligible articles. Eligibility criteria included studies evaluating doctor-to-dermatologist Australian SAFT services provided to Australians for all skin conditions but excluded the studies that solely focused on skin cancers. Data on study design, setting, population, SAFT model, referral characteristics, patient, and general practitioner perspectives, diagnostic concordance, and measured outcomes such as follow up, investigation and waiting time were extracted. Quality of the included studies was assessed using CASP tools. Synthesis reveals that SAFT can be used for patients with any dermatological condition, provides more accurate diagnostics compared to cases without dermatologist input, may reduce waiting times for dermatological expertise, and users generally had positive experiences with SAFT. Although results are positive, this review reveals the heterogenous nature of the literature on SAFT in Australia and a need to establish a uniform approach to assessing the outcomes and impacts of such services.

Quantitative Simulation of Enzymatic Breakdown of Alcohol in Human Metabolism.

The breakdown of ethanol, the active chemical in alcohol, is tightly regulated by the body, yet alcohol intoxication occurs in thousands of Americans annually. Many factors contribute to the concentration of ethanol in the bloodstream and the tolerance an individual has, including body size, previous drinking experience, and liver functionality. We propose a model that estimates both the blood alcohol concentration and the concentration of acetaldehyde (the toxic intermediate during catabolism) in the liver over time to quantify organ damage for an average person. From the current literature, we derived ordinary differential equations that govern the absorption of ethanol in the body and extended it with the metabolic enzyme mechanisms. We also altered the parameters of our system in order to show the effects of Asian flush, which impairs the body's processing of acetaldehyde. We demonstrated the accumulation of acetaldehyde in Asian flush patients was about 660 times higher compared to those without the disease.Clinical relevance-With further improvements and personalization, our model would be able to quantitatively describe the effects of alcohol consumption without having volunteers go through repetitive trials with extensive exposure to alcohol. Liver damage can also be estimated with the acetaldehyde buildup predicted by the model.

Stretchable, Adhesive, and Biocompatible Hydrogel Based on Iron-Dopamine Complexes.

Hydrogels' exceptional mechanical strength and skin-adhesion characteristics offer significant advantages for various applications, particularly in the fields of tissue adhesion and wearable sensors. Herein, we incorporated a combination of metal-coordination and hydrogen-bonding forces in the design of stretchable and adhesive hydrogels. We synthesized four hydrogels, namely PAID-0, PAID-1, PAID-2, and PAID-3, consisting of acrylamide (AAM), N,N'-methylene-bis-acrylamide (MBA), and methacrylic-modified dopamine (DA). The impact of different ratios of iron (III) ions to DA on each hydrogel's performance was investigated. Our results demonstrate that the incorporation of iron-dopamine complexes significantly enhances the mechanical strength of the hydrogel. Interestingly, as the DA content increased, we observed a continuous and substantial improvement in both the stretchability and skin adhesiveness of the hydrogel. Among the hydrogels tested, PAID-3, which exhibited optimal mechanical properties, was selected for adhesion testing on various materials. Impressively, PAID-3 demonstrated excellent adhesion to diverse materials and, combined with the low cytotoxicity of PAID hydrogel, holds great promise as an innovative option for biomedical engineering applications.

Electroactive and Stretchable Hydrogels of 3,4-Ethylenedioxythiophene/thiophene Copolymers.

Hydrogels are conductive and stretchable, allowing for their use in flexible electronic devices, such as electronic skins, sensors, human motion monitoring, brain-computer interface, and so on. Herein, we synthesized the copolymers having various molar ratios of 3,4-ethylenedioxythiophene (EDOT) to thiophene (Th), which served as conductive additives. With doping engineering and incorporation with P(EDOT-co-Th) copolymers, hydrogels have presented excellent physical/chemical/electrical properties. It was found that the mechanical strength, adhesion ability, and conductivity of hydrogels were highly dependent on the molar ratio of EDOT to Th of the copolymers. The more the EDOT, the stronger the tensile strength and the greater the conductivity, but the lower the elongation break tends to be. By comprehensively evaluating the physical/chemical/electrical properties and cost of material use, the hydrogel incorporated with a 7:3 molar ratio P(EDOT-co-Th) copolymer was an optimal formulation for soft electronic devices.

Perception and reaction of Nanyang Technological University (NTU) researchers to different forms of research integrity education modality.

BACKGROUND: Research and academic institutions use various delivery channels to deliver Research Integrity (RI) education in their communities. Yet there is no consensus on the best delivery method and the effectiveness of these channels in inculcating a positive RI culture varies across institutions. Hence, this study aimed to understand the preferences of the research community in Nanyang Technological University (NTU), Singapore. METHODS: An online survey was conducted on NTU research community to understand their experience with, and preference for each RI education mode offered in NTU. The RI education modes surveyed in the general ranking question are Data Management Plan (DMP) workshops, Epigeum e-Learning, Compass e-newsletter (email), and NTU policy on Research Integrity and Responsible Conduct of Research. There were 242 responses, comprising 50% research students, 32.2% research staff and 17.8% faculty members. Non-parametric statistical techniques were used to analyse preferences across different RI education modes and within sub-groups (i.e., fields, age, native language, roles in research community). RESULTS: More than 92% of respondents subscribed to the importance of RI education, but with different preferences for education modes. With respect to RI education in NTU, Compass e-newsletters were ranked the lowest (p < 0.05). Most felt that they were too wordy and unengaging, making it difficult to absorb information. Similarly, Epigeum e-Learning (p < 0.05) and 'policy' (p < 0.05) were found to be too lengthy in presentation. The compulsory NTU RI education modes (Epigeum e-learning and 'policy') enjoyed higher participation rates of 70-80% compared with 32-37% for the self-regulated modes (DMP workshop and e-newsletter). This suggests that regulatory mechanisms are still necessary to promote participation in RI education, and thus, core RI education content should be made compulsory in research/academic institutions. Although Epigeum is a compulsory course, some may not have participated in the programme due to technical issues or they might have forgotten to participate in the programme within the permissible timeframe. For all four RI education modes in NTU, the lack of awareness was among the top cited reasons for not participating. CONCLUSIONS: Most NTU researchers perceived RI education positively although they may have reservations for some approaches. Conversely, e-Learning is favored over all the other modes except for the mode of Policy. Findings from this study are useful for improving the design of RI education strategies to be more appealing to the research community by enhancing user experience in terms of user-friendliness, relevance to specialisation, providing concise information and better presentation of materials For institutions with similar modes of RI education as NTU, these results may be relevant in improving participation rates and presentation of RI education modes, such as the use of infographics and more concise information.

The Development of Health Self-Management Among Adolescents With Chronic Conditions: An Application of Self-Determination Theory.

PURPOSE: The purpose of the study was to better understand the progressive development of health self-management among adolescents and emerging adults (AEAs) with chronic medical conditions in order to identify opportunities to prepare AEA for transition to adult-based care. METHODS: Twenty-three AEA aged 17-20 years with renal, inflammatory bowel, or rheumatologic diseases, and their parents, completed individual semistructured interviews describing each AEA's health self-management. Self-Determination Theory was used to frame interview questions, including the constructs of competence, autonomy, and autonomy support. Transcripts were analyzed using directed content analysis. RESULTS: Four themes emerged: Development of Competence in Self-Management; Autonomy: Motivations to Self-Manage; Ways Important Others Support or Hinder Independence; and Normal Adolescent Development. AEA's competency and autonomy increased as they progressed from lack of knowledge about self-management to having knowledge without doing tasks, and, ultimately, to independent completion of tasks. Motivations to self-manage included avoiding sickness/weakness and wanting to engage in activities. Parents and providers supported AEA's autonomy through teaching and transferring responsibility. Parental fear/lack of trust in AEA's ability to self-manage hindered development of AEA's autonomy, producing anxiety. Normal adolescent development impacted timing of self-management task mastery. CONCLUSIONS: As AEA gain competence in increasingly complex self-management tasks, they assume greater responsibility for managing their health. Competence and autonomy are facilitated by a feedback loop: AEA successful self-management increased parent trust, enabling the parent to transfer responsibility for more complex tasks. Conversely, parents' fear of the AEA doing wrong hinders transfer of responsibility, limiting competence and autonomy. Health-care providers play an important role in fostering autonomy.

Integration of telehealth services in the healthcare system: with emphasis on the experience of patients living with HIV.

The US Health Resources and Services Administration defines telehealth as the use of electronic information and telecommunications technologies to support long-distance clinical healthcare, patient and professional health-related education, public health and health administration. Many studies have supported the use of telehealth to increase convenience to patients, improve patient satisfaction, diminish healthcare disparities, and reduce cost that will ultimately lead to improvement in clinical outcomes and quality of care. However, guaranteeing confidentiality, educating patients and providers, and obtaining insurance reimbursement are some of the challenges that face the implementation of telehealth program. The use of telehealth has been investigated in acute infections, such as endocarditis and chronic infections as in hepatitis C, and HIV. The purpose of this review is to focus on the use of telehealth services for people living with HIV (PLWH). For PLWH, telehealth could be particularly useful by connecting specialty providers to an underserved population and addressing many of the factors identified as barriers to HIV care. To date, the literature supports the use of telehealth for the management of chronic diseases including HIV. Most of the studies showed a high acceptability and positive experience with telehealth services among PLWH. However, fewer studies have evaluated telemedicine for chronic direct care of PLWH. Well-designed studies are needed to show that the implementation of telehealth could improve the HIV care continuum. In addition, future research should focus on identifying the group of patients that could benefit the most from such intervention.

Seasonal variation of chemical characteristics of fine particulate matter at a high-elevation subtropical forest in East Asia.

The aim of this study was to chemically characterize the fine particulate matter (PM2.5) at a subtropical forest in East Asia under the influences of anthropogenic and biogenic sources and a complex topographic setting. Four seasonal campaigns were conducted at the Xitou Experimental Forest in central Taiwan from the winter of 2013 to the autumn of 2014. The results indicated that the ambient levels and chemical features of PM2.5 exhibited pronounced seasonal variations. Non-sea-salt sulfate (nss-SO42-) constituted the major component of PM2.5, followed by ammonium (NH4+) and nitrate (NO3-) during winter, summer and autumn. However, it was revealed that the mass fraction of NO3- increased to be comparable with that of nss-SO42- in springtime. The mass contribution of secondary organic carbon (SOC) to PM2.5 peaked in summer (13.2%), inferring the importance of enhanced photo-oxidation reactions in SOC formation. Diurnal variations of O3 and SO2 coincided with each other, suggesting the transport of aged pollutants from distant sources, whereas CO and NOx were shown to be under the influences of both local and regional sources. Notably high sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR) were observed, which were 0.93 ±â€¯0.05 and 0.39 ±â€¯0.20, respectively. Precursor gases (i.e. SO2 and NOx) could be converted to sulfate and nitrate during the transport by the uphill winds. Furthermore, due to the high relative humidity at Xitou, enhanced aqueous-phase and/or heterogeneous reactions could further contribute to the formation of sulfate and nitrate at the site. This study demonstrated the significant transport of urban pollutants to a subtropical forest by the mountain-valley circulations as well as the long-range transport from regional sources, whereas the implications of which for regional climate change necessitated further investigation.

Vulnerability of indigenous health to climate change: a case study of Uganda's Batwa Pygmies.

The potential impacts of climate change on human health in sub-Saharan Africa are wide-ranging, complex, and largely adverse. The region's Indigenous peoples are considered to be at heightened risk given their relatively poor health outcomes, marginal social status, and resource-based livelihoods; however, little attention has been given to these most vulnerable of the vulnerable. This paper contributes to addressing this gap by taking a bottom-up approach to assessing health vulnerabilities to climate change in two Batwa Pygmy communities in rural Uganda. Rapid Rural Appraisal and PhotoVoice field methods complemented by qualitative data analysis were used to identify key climate-sensitive, community-identified health outcomes, describe determinants of sensitivity at multiple scales, and characterize adaptive capacity of Batwa health systems. The findings stress the importance of human drivers of vulnerability and adaptive capacity and the need to address social determinants of health in order to reduce the potential disease burden of climate change.

Impact of anthropogenic emissions and open biomass burning on regional carbonaceous aerosols in South China.

Carbonaceous aerosols were studied at three background sites in south and southwest China. Hok Tsui in Hong Kong had the highest concentrations of carbonaceous aerosols (OC=8.7±4.5µg/m(3), EC=2.5±1.9µg/m(3)) among the three sites, and Jianfeng Mountains in Hainan Island (OC=5.8±2.6µg/m(3), EC=0.8±0.4µg/m(3)) and Tengchong mountain over the east edge of the Tibetan Plateau (OC=4.8±4.0µg/m(3), EC=0.5±0.4µg/m(3)) showed similar concentration levels. Distinct seasonal patterns with higher concentrations during the winter, and lower concentrations during the summertime were observed, which may be caused by the changes of the regional emissions, and monsoon effects. The industrial and vehicular emissions in East, Southeast and South China, and the regional open biomass burning in the Indo-Myanmar region of Asia were probably the two major potential sources for carbonaceous matters in this region.

An overview of L-2-hydroxyglutarate dehydrogenase gene (L2HGDH) variants: a genotype-phenotype study.

L-2-Hydroxyglutaric aciduria (L2HGA) is a rare, neurometabolic disorder with an autosomal recessive mode of inheritance. Affected individuals only have neurological manifestations, including psychomotor retardation, cerebellar ataxia, and more variably macrocephaly, or epilepsy. The diagnosis of L2HGA can be made based on magnetic resonance imaging (MRI), biochemical analysis, and mutational analysis of L2HGDH. About 200 patients with elevated concentrations of 2-hydroxyglutarate (2HG) in the urine were referred for chiral determination of 2HG and L2HGDH mutational analysis. All patients with increased L2HG (n=106; 83 families) were included. Clinical information on 61 patients was obtained via questionnaires. In 82 families the mutations were detected by direct sequence analysis and/or multiplex ligation dependent probe amplification (MLPA), including one case where MLPA was essential to detect the second allele. In another case RT-PCR followed by deep intronic sequencing was needed to detect the mutation. Thirty-five novel mutations as well as 35 reported mutations and 14 nondisease-related variants are reviewed and included in a novel Leiden Open source Variation Database (LOVD) for L2HGDH variants (http://www.LOVD.nl/L2HGDH). Every user can access the database and submit variants/patients. Furthermore, we report on the phenotype, including neurological manifestations and urinary levels of L2HG, and we evaluate the phenotype-genotype relationship.

Comparing polybrominated diphenyl ethers (PBDEs) in airborne particles in Guangzhou and Hong Kong: sources, seasonal variations and inland outflow.

The historical application/usage and management of chemicals in Hong Kong have been distinctively different from mainland China. In the present study, polybrominated diphenyl ethers (PBDEs) were measured in year-round atmospheric particle samples collected from urban Hong Kong and Guangzhou for comparison. The concentrations of BDE-209 and Sigma9PBDEs (defined as the sum of BDE-28, -47, -66, -100, -99, -154, -153, -138 and -183) in Guangzhou ranged from 758 to 21,900 pg m(-3) and from 31.8 to 3320 pg m(-3), respectively, and in Hong Kong ranged from 8.5 to 895 pg m(-3) and from 1.0 to 386 pg m(-3), respectively. Elevated concentrations of PBDEs were observed in Guangzhou, showing significant atmospheric PBDE pollution. BDE-209, -47, and -99 were the dominant congeners in all the samples, suggesting that the widely used commercial penta- and deca-BDE products were the original sources. Distinct seasonal patterns were observed in the PBDE concentrations of aerosols in Hong Kong, higher during the winter monsoon period, and lower during summertime. The less distinct seasonal variations of PBDE concentrations in the aerosols of Guangzhou suggested the dominance of local pollution sources around the city. Significant correlations were found between BDE-209 and organic carbon (OC) or elemental carbon (EC) in the two cities, suggesting that combustion may be an important pathway introducing BDE-209 to the atmosphere. The lower BDE-209 concentrations along with higher OC/EC ratios implied that a quick loss of BDE-209 may occur during the aerosol aging processes. Back trajectory analysis showed that the high PBDE concentrations observed in Hong Kong may be related to the outflows from the inland area of the Pearl River Delta (PRD) by prevailing the northeast or northwest wind in winter.

Seven thousand years of records on the mining and utilization of metals from lake sediments in central China.

A 268 cm section of sediment core from Liangzhi Lake in Hubei province in central China was used to assess the use and accumulation of metals in the lake in the past 7,000 years. The concentrations of trace metals, including Cu, Pb, Ni, and Zn, and major elements, Ca, Fe, and Mg, in a 14C- dated segment of sediment core were analyzed. Historical trends on the input of metals to Liangzhi Lake from around 5000 BC to the present were recorded in the sediments, representing about 7,000 years of history on the mining and utilization of metals in central China. The concentrations of Cu, Ni, Pb, and Zn increased gradually from about 3000 +/- 328 BC, indicating the start of the Bronze Age in ancient China. During the period 467 +/- 257 to 215 +/- 221 AD, there was a rapid increase in the concentrations of these metals in the sediments, indicating enormous inputs of these metals at that time. This era corresponded to China's Warring States Period (475- 221 BC) and the early Han Dynasty (206 BC-220 AD), during which copper and lead were extensively used in making bronze articles such as vessels, tools, and weapons. From 1880 +/- 35 AD to the early 1900s, there was also a significant increase in the concentrations of metals such as Cu, Ni, and Pb, which probably reflected the metal emissions and utilization during the early period of industrial development and weapon manufacture during the wars in China. The Pb isotopic analysis showed that the surface and subsurface sediments had lower 206Pb/207Pb and 208Pb/ 207Pb ratios than the deeper layers, reflecting the additional input of Pb from mining activities that took place during the Bronze Age era and in modern times. This study provides direct evidence of the environmental impact of the mining and utilization of metals in the last 7,000 years in one of the important regions of Chinese civilization.

Passive air sampling of DDT, chlordane and HCB in the Pearl River Delta, South China: implications to regional sources.

The Pearl River Delta (PRD) is one of the largest fast-developing economic zones in China. Hong Kong and the mainland part of the PRD differed in socio-economic development history and chemical management policies. Polyurethane foam (PUF)-passive air sampling (PAS) was deployed at 21 regional air quality monitoring stations across the PRD in summer and winter, respectively. Dichloro-diphenyl-trichloroethane (DDT), chlordane and hexachlorobenzene (HCB) were analyzed with GC-MS. High total DDT (240-3700 pg m(-3)) and chlordane (100-2600 pg m(-3)) concentrations were observed. Concentrations of DDTs and chlordane were higher in summer than winter; HCB vice versa. Spatially, the mainland part of the PRD generally displayed higher DDT concentrations than Hong Kong. Antifouling paint for fishing ships in coastal China was suggested to be an important current DDT source in the coast. The reason is unknown for the very low trans-/cis-chlordane (TC/CC) ratios (0.27) found in the mainland in winter. HCB concentrations were relatively uniform across the PRD, and long range transport of HCB from inland/North China to the PRD in winter was suggested.

Hemiconvulsion-hemiplegia-epilepsy syndrome as a presenting feature of L-2-hydroxyglutaric aciduria.

L-2-hydroxyglutaric aciduria was diagnosed in a 9-month-old female infant after a complex febrile convulsion with subsequent transient left-sided hemiplegia. The symptoms were consistent with acute hemiconvulsion-hemiplegia-epilepsy syndrome. Magnetic resonance imaging (MRI) of the brain revealed distinct white-matter abnormalities in the bifrontal and bioccipital periventricular area and increased signal intensity in the lenticular, caudate, and dentate nuclei, consistent with L-2-hydroxyglutaric aciduria. Increased concentrations of L-2-hydroxyglutaric acid were detected in the urine, plasma, and cerebrospinal fluid. The patient was homozyous for the p.Lys81Glu (c.241A>G) missense mutation in the L-2-HGA gene, confirming the diagnosis of L-2-hydroxyglutaric aciduria. Acute hemiconvulsion-hemiplegia-epilepsy syndrome has not been reported as a presenting feature in L-2-hydroxyglutaric aciduria. In patients with prolonged or complicated febrile seizures such as hemiconvulsion-hemiplegia-epilepsy syndrome, L-2-hydroxyglutaric aciduria should be included in the differential diagnosis, especially in children with concomitant macrocephaly.

Gender-associated differences in the psychosocial and developmental outcome in patients affected with the bladder exstrophy-epispadias complex.

OBJECTIVE: To identify problems in the long-term psychosocial and developmental outcome specific to patients with the bladder exstrophy-epispadias complex (BEEC), using a self-developed semi-structured questionnaire, as there are various techniques of reconstruction to repair BEEC but to date neither patients nor surgeons have a clear answer about which type gives the most acceptable long-term results. PATIENTS AND METHODS: Increasingly many patients with BEEC reach adulthood and wish to have sexual relationships and families. To date, no studies have used disease-specific psychological instruments to measure the psychosocial status of patients with BEEC. Thus we contacted 208 patients with BEEC, and 122 were enrolled, covering the complete spectrum of the BEEC. The data assessed included the surgical reconstruction, subjective assessment of continence, developmental milestones, school performance and career, overall satisfaction in life, disease-specific fears and partnership experiences in patients aged >18 years. We compared affected females and males to assess gender-associated differences in quality of life. RESULTS: Affected females had more close friendships, fewer disadvantages in relation to healthy female peers and more partnerships than the males. Family planning seemed to be less of a problem in affected females. There were no gender differences in the adjustments within school and professional career, which was very good in general. CONCLUSION: Future studies are needed to assess the disease-specific anxieties, considering gender-specific differences.

Metal contamination in urban, suburban, and country park soils of Hong Kong: a study based on GIS and multivariate statistics.

The urban environment quality is of vital importance as the majority of people now live in cities. Due to the continuous urbanisation and industrialisation in many parts of the world, metals are continuously emitted into the terrestrial environment and pose a great threat on human health. An extensive survey was conducted in the highly urbanised and commercialised Hong Kong Island area (80.3 km2) of Hong Kong using a systematic sampling strategy of five soil samples per km2 in urban areas and two samples per km2 in the suburban and country park sites (0-15 cm). The analytical results indicated that the surface soils in urban and suburban areas are enriched with metals, such as Cu, Pb, and Zn. The Pb concentration in the urban soils was found to exceed the Dutch target value. The statistical analyses using principal component analysis (PCA) and cluster analysis (CA) showed distinctly different associations among trace metals and the major elements (Al, Ca, Fe, Mg, Mn) in the urban, suburban, and country park soils. Soil pollution maps of trace metals (Cd, Co, Cr, Cu, Ni, Pb, and Zn) in the surface soils were produced based on geographical information system (GIS) technology. The hot-spot areas of metal contamination were mainly concentrated in the northern and western parts of Hong Kong Island, and closely related to high traffic conditions. The Pb isotopic composition of the urban, suburban, and country park soils showed that vehicular emissions were the major anthropogenic sources for Pb. The 206Pb/207Pb and 208Pb/207Pb ratios in soils decreased as Pb concentrations increased in a polynomial line (degree=2).