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1.
Chemosphere ; 263: 128292, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297234

RESUMO

BACKGROUND AND OBJECTIVES: A cross-sectional biomonitoring study was performed in Modena (Italy) to assess trace element levels in toenails in a population living near a municipal solid waste incinerator (SWI), and investigate potential differences in their concentrations according to SWI emission exposure and other environmental and behavioral factors. METHODS: During the winter 2013/14 eligible subjects, aged 18-69 yrs, living within 4 km from SWI, were randomly selected from the population register. Toxic and essential element concentrations (As, Cd, Cr, Cu, Mn, Ni, Pb, Se, Zn) were analyzed in 489 toenail samples. Individual exposure to SWI emissions was estimated by using, as a tracer, fall-out maps of emitted particulate matter. Information on anthropometric parameters, lifestyles, diet, and road traffic, residential and work exposures were collected by questionnaires and objective measurements. Multivariate logistic regression analyses were carried out, separately for females and males. RESULTS: Excluding As, toxic elements were found, usually at low levels, in many samples, while essential elements, especially Cu and Zn, showed higher levels. Overall, no clear relationships between element levels and SWI exposure were observed, whereas associations with other environmental and lifestyle factors were found, including local food consumption, smoking and occupation. CONCLUSIONS: The low pollutant concentrations measured in SWI emissions could explain the absence of clear patterns in toenail levels across SWI exposure levels. The associations observed with other factors suggest that, at least in this specific population, other environmental exposures and personal behaviors could act as more important predictors of trace element uptake.


Assuntos
Oligoelementos , Adolescente , Adulto , Idoso , Estudos Transversais , Monitoramento Ambiental , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Unhas/química , Resíduos Sólidos/análise , Oligoelementos/análise , Adulto Jovem
2.
Ecotoxicol Environ Saf ; 202: 110933, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800217

RESUMO

Parabens are used as antimicrobial preservatives in a range of consumer products. However, very limited information is available about the association between use of personal care products and paraben burden in human tissues. Accumulation of parabens in some non-destructive biomarkers (such as human fingernail) is essential for paraben biomonitoring. In this study, 50 human fingernail samples were collected from Nanjing, China. A subset of participants (n = 32) also provided their face cream samples (as the representative of personal care products). Six parabens, including methyl- (MeP), ethyl- (EtP), propyl- (PrP), butyl- (BuP), heptyl- (HeP), and benzyl-parabens (BzP), together with their major metabolites were measured in the fingernail and face cream samples. Total concentrations of parabens and their major metabolites were 39.9-27400 ng/g in fingernails. MeP, PrP and EtP were the three dominant parabens in fingernails with median values of 3140, 1290, and 127 ng/g, respectively. Significantly higher levels in female fingernails than those in male fingernails were observed for MeP, PrP, EtP, BuP, and the MeP metabolite (methyl protocatechuate, OH-MeP) (p < 0.05). Adult fingernails contained greater concentrations of MeP and PrP than juvenile fingernails (p < 0.05). Positive correlations were observed for EtP (R = 0.36, p < 0.05) and BuP (R = 0.48, p = 0.008) concentrations between the fingernail and face cream samples. Our work is a preliminary study trying to explore the quantitative relationship between paraben concentrations in human body and use of personal care products. The result here provides a direct evidence that use of personal care products is one of the major sources for human exposure to parabens.


Assuntos
Cosméticos/análise , Unhas/química , Parabenos/análise , Adolescente , Adulto , Antibacterianos , Anti-Infecciosos , Biomarcadores , China , Feminino , Humanos , Masculino , Parabenos/metabolismo , Conservantes Farmacêuticos/análise , Conservantes Farmacêuticos/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-32527015

RESUMO

Behavioral problems are multifactorial and includes perinatal, maternal, family, parenting, socio-economic and personal risk factors, but less is known about the association of postnatal heavy metals on children's behavioral problems in Pacific Island children. METHODS: A cohort of eligible nine-year-old children within a Pacific Island Families longitudinal study were recruited for a cross-sectional study. Child behavior problems were assessed using the child behavior checklist. Heavy metals (including Ni, Cu, Pb, Al, Cr and Cd) were determined in toenails, after acid digestion and analyzed using inductively coupled plasma mass spectrometry. Other factors such as lifestyle (smoking in pregnancy), health outcomes (obesity, health status), demographics (gender, ethnicity, parents' marital status) and socioeconomic status (household income levels) were also collected. The statistical analysis included t-tests for independent sample and Mann-Whitney U-test, and chi-square or Fisher's exact tests of independence for comparisons of the proportions. Regression models tested the hypothesized risk factors for behavior outcomes. RESULTS: This observational study enrolled 278 eligible Pacific Island children living in Auckland, New Zealand. The prevalence of behavioral problems in the clinical range was high (22%) but there was no significant association between heavy metals in toenails and adverse behavioral outcomes. CONCLUSION: Regular monitoring and assessments of children for environmental risk factors, as well as social and lifestyle factors for behavior problems, continues. Alternative indicators of exposure to heavy metal should be evaluated.


Assuntos
Metais Pesados , Unhas , Comportamento Problema , Criança , Estudos Transversais , Exposição Ambiental , Monitoramento Ambiental , Feminino , Humanos , Estudos Longitudinais , Masculino , Metais Pesados/análise , Unhas/química , Nova Zelândia , Ilhas do Pacífico , Gravidez , Fatores de Risco
4.
Anal Bioanal Chem ; 412(8): 1847-1861, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32020317

RESUMO

Biomonitoring for human exposure to lead, arsenic, mercury, and other toxic metal(loid)s often relies on analyzing traditional biospecimens such as blood and urine. While biomonitoring based on blood and urine is well-established, non-traditional biospecimens such as hair and nails can offer the potential to explore past exposures as well as the advantages of non-invasive collection and ease of storage. The present study describes the production of four reference materials (NYS RMs 18-01 through 18-04) based on caprine horn, a keratinized tissue similar to human hair and nails, intended to serve as a resource for calibration, quality control, and method validation purposes. The elemental content and homogeneity of these candidate reference materials were characterized for 17 elements using inductively coupled plasma mass spectrometry (ICP-MS). Commutability between two or more of the NYS caprine horn RMs and human nails was established for 8 elements (Ba, Ca, Cr, Cu, Mn, Pb, Sr, and Zn) based on analysis by ICP-MS/MS and ICP-optical emission spectrometry. The development and optimization of an ICP-MS/MS instrumental method for the determination of 17 elements in keratinized tissues is described. The method was validated against three certified reference materials based on human hair showing good accuracy and method repeatability better than 25% for all analytes. This study also describes sample preparation issues and addresses common challenges including surface contamination, microwave digestion, matrix effects, and spectral interferences in inorganic mass spectrometry. New York State Department of Health Keratin Matrix Reference Materials. Graphical abstract.


Assuntos
Queratinas/química , Oligoelementos/análise , Animais , Calibragem , Cabras , Cabelo/química , Humanos , Limite de Detecção , Unhas/química , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , Oligoelementos/normas
5.
Chemosphere ; 246: 125790, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918100

RESUMO

Widespread contamination of arsenic (As) has become a global public health concern. Exposure to As causes respiratory complications. Asthma, a major respiratory complication, is increasing worldwide. However, the effect of chronic As exposure on the risk of asthma remains to be clarified. This study aims to examine the associations between As exposure (water, hair and nail As) and the risk of asthma among 842 individuals exposed to a wide range of As concentrations through drinking water in Bangladesh. Subjects' As exposure levels were measured with ICP-MS. Lung function was examined by a handheld spirometer. Characteristic features of asthma were evaluated by bronchodilator-mediated reversibility in airway obstruction and asthma-like symptoms through a structured questionnaire. Total serum immunoglobulin E (sIgE) levels were measured by immunoassay. As exposure metrics showed inverse associations with lung function measures (FEV1, FEV6, and FEV1/FEV6 ratio) and positive associations with the risks of airway obstruction (AO), reversible airway obstruction (RAO), and asthma-like symptoms. The majority of AO patients (70 of 97) were RAO with one or more characteristic symptoms of asthma. Intriguingly, subjects' As exposure levels showed positive associations with total sIgE levels. Total sIgE in RAO patients was significantly (p < 0.001) higher than that in the control group. Thus the results revealed that chronic As exposure was associated with the risk of the characteristic features of asthma. Additionally the association between As exposure and subjects' total sIgE levels and an elevated level of total sIgE in RAO group suggested that As exposure-related asthma might be allergic in nature.


Assuntos
Arsênico/análise , Asma/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Adulto , Arsênico/metabolismo , Intoxicação por Arsênico/epidemiologia , Bangladesh/epidemiologia , Poluentes Ambientais/análise , Feminino , Cabelo/química , Humanos , Masculino , Pessoa de Meia-Idade , Unhas/química
7.
Environ Geochem Health ; 42(4): 1197-1209, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31317372

RESUMO

Potentially harmful elements (PHEs) manganese (Mn), cobalt (Co), copper (Cu), lead (Pb), nickel (Ni) and zinc (Zn) were measured in human hair/nails, staple crops and drinking water to ascertain the level of exposure to dust transference via wind and rain erosion for members of the Mugala community living near a mine waste dump in the Zambian Copperbelt. The mean PHE concentrations of hair in decreasing order were Zn (137 ± 21 mg/kg), Cu (38 ± 7 mg/kg), Mn (16 ± 2 mg/kg), Pb (4.3 ± 1.9 mg/kg), Ni (1.3 ± 0.2 mg/kg) and Cr (1.2 ± 0.2 mg/kg), Co (0.9 ± 0.2 mg/kg) and Cd (0.30 ± 0.02 mg/kg). Whilst for toenails the decreasing order of mean concentrations was Zn (172 ± 27 mg/kg), Cu (30 ± 5 mg/kg), Mn (12 ± 2 mg/kg), Pb (4.8 ± 0.5 mg/kg), Ni (1.7 ± 0.14 mg/kg) and Co (1.0 ± 0.02 mg/kg), Cr (0.6 ± 0.1 mg/kg) and Cd (0.1 ± 0.002 mg/kg). The concentration of these potentially harmful elements (PHEs) varied greatly among different age groups. The results showed that Mn, Co, Pb, Cd and Zn were above the interval values (Biolab in Nutritional and environmental medicine, Hair Mineral Analysis, London, 2012) at 0.2-2.0 mg/kg for Mn, 0.01-0.20 mg/kg for Co, < 2.00 mg/kg for Pb, < 0.10 mg/kg for Cd and 0.2-2.00 mg/kg for Zn, whilst Ni, Cu and Cr concentrations were within the normal range concentrations of < 1.40 mg/kg, 10-100 mg/kg and 0.1-1.5 mg/kg, respectively. Dietary intake of PHEs was assessed from the ingestion of vegetables grown in Mugala village, with estimated PHE intakes expressed on a daily basis calculated for Mn (255), Pb (48), Ni (149) and Cd (33) µg/kg bw/day. For these metals, DI via vegetables was above the proposed limits of the provisional tolerable daily intakes (PTDIs) (WHO in Evaluation of certain food additive and contaminants, Seventy-third report of the Joint FAO/WHO Expert Committee on Food Additives, 2011) for Mn at 70 µg/kg bw/day, Pb at 3 µg/kg bw/day, Ni and Cd 5 µg/kg bw/day and 1 µg/kg bw/day, respectively. The rest of the PHEs listed were within the PTDIs limits. Therefore, Mugala inhabitants are at imminent health risk due to lead, nickel and cadmium ingestion of vegetables and drinking water at this location.


Assuntos
Exposição Ambiental/análise , Cabelo/química , Metais/análise , Unhas/química , Adolescente , Adulto , Criança , Exposição Dietética/análise , Água Potável/análise , Poeira/análise , Biomarcadores Ambientais , Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Humanos , Verduras , Instalações de Eliminação de Resíduos , Adulto Jovem , Zâmbia
8.
Ecol Food Nutr ; 59(2): 130-153, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31630556

RESUMO

Nutrition transition theory describes a progressive substitution of local staples for industrialized processed foods in local diets, a process documented diversely across world regions, and increasingly observed in rural areas of the global south. Here we examine the role of conditional cash transfer programs, in particular the emblematic Brazilian Bolsa Família (BFP), in driving nutritional transition in rural areas of the Amazon. Based on ethnographic research with both participating and nonparticipating women in the Amanã Sustainable Development Reserve (SDR), our analysis integrates Food Frequency Questionnaires (FFQ), seasonal 24-hour food intake recalls, and stable isotope ratios in fingernails to examine dietary behavioral change. Contrary to dietary changes observed elsewhere in the Amazon, participation in the BFP is not associated with a significant substitution of local staples for industrialized processed foods in Amanã. While an increase in the consumption of some industrialized foods was observed, it has been selective and it has not changed the structure of diets. Factors such as social and cultural value of local staples, resident's involvement with the SDR, their relationship with lake and upland forest and agricultural environments, and limited market access have buffered the expansion of industrialized processed foods as observed elsewhere.


Assuntos
Dieta/economia , Dieta/etnologia , Assistência Alimentar/economia , Programas Governamentais/economia , Adulto , Brasil/etnologia , Características Culturais , Inquéritos sobre Dietas , Características da Família , Feminino , Manipulação de Alimentos , Humanos , Isótopos/análise , Unhas/química , População Rural/tendências
9.
J Anal Toxicol ; 44(1): 69-74, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30855673

RESUMO

Nail analysis can be performed as a substitute or complement to hair analysis for the retrospective determination of psychotropic drugs consumption in forensic contexts. The application of nail analysis in a "chemsex" context is reported herein. An ultra-performance liquid chromatography-tandem mass spectrometry method was developed to quantify the most common drugs of abuse, synthetic cannabinoids, synthetic cathinones and GHB in fingernails and toenails of individuals presumptively using these drugs in music and sex settings. Results were compared to the concentrations measured in hair. Nail and hair keratin matrices were digested with VMA-TM3® buffer reagent and underwent a solid phase extraction before chromatographic separation with reversed phase columns and a linear gradient elution with 5 mM ammonium formate and acetonitrile, for detecting classic drugs of abuse, or 0.1% formic acid and methanol, for detecting synthetic cathinones, synthetic cannabinoids, and GHB. Analytes were detected with a triple quadrupole mass spectrometer operated in multiple reaction monitoring mode after positive electrospray ionization. Nails of individuals practicing "chemsex" contained at least three different psychoactive drugs, and up to eight drugs simultaneously. Identified drugs included cocaine, benzoylecgonine, cocaethylene, delta-9-tetrahydrocannabinol, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine, ketamine, norketamine, mephedrone, methylone, 4-methyletcathinone, methcathinone, γ-hydroxybutyric acid (GHB) and γ-butyrolactone. Most used drugs were MDMA and GHB followed by cocaine and ketamine. Drugs concentrations ranged from 0.1 to 690 ng/mg in fingernails. In the two individuals who also provided toenails, concentrations were always higher in fingernails than in toenails, while in two other individuals who donated also hair, concentrations in this latter matrix were either higher or lower than those measured in fingernails. This study demonstrated that nails may well represent an appropriate non-conventional biological matrix to provide additional information in forensic toxicology.


Assuntos
Drogas Ilícitas/análise , Unhas/química , Psicotrópicos/análise , Detecção do Abuso de Substâncias/métodos , Anfetamina , Cromatografia Líquida , Cocaína/análogos & derivados , Dronabinol/análise , Toxicologia Forense , Cabelo/química , Humanos , Hidroxibutiratos , Extração em Fase Sólida
10.
Biol Trace Elem Res ; 194(1): 34-47, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31098833

RESUMO

Lymphoma arises from cells of the immune system and trace metals augment the immune system and their imbalance may promote immunological disorders including tumorigenesis. The primary aim of the present investigation was to evaluate the levels of essential/toxic trace metals in the nails of non-Hodgkin and Hodgkin lymphomas patients in comparison with controls. The samples collected from patients and controls were digested in the mixture of HNO3-HClO4 and selected trace metals were analysed using flame atomic absorption spectrometry. The results showed that mean concentrations of some elements (Pb, Ni, Cd, Cu and Cr) in nails of non-Hodgkin lymphoma patients were significantly elevated (p < 0.05) than that of the controls whereas mean contents of Pb, Cu, Cd and Cr were observed to be significantly higher in the nails of Hodgkin lymphoma patients compared with healthy donors. Additionally, correlation study pointed out significantly diverse mutual associations of the trace metals among the patients and controls. The present results revealed noticeable disparities in the metal concentrations based on gender, food habits, tobacco use and types/stages of the donor's groups. Overall, the pathogenesis of disease significantly affected the trace metal balance in both patients' groups.


Assuntos
Doença de Hodgkin/diagnóstico , Linfoma não Hodgkin/diagnóstico , Unhas/química , Oligoelementos/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Bull Environ Contam Toxicol ; 104(1): 90-95, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31728558

RESUMO

We conducted exposure assessment using toenails from 20 fishermen living in Bodo City, a community of the Niger delta region in Nigeria. This community has been affected by over 4000 oil spills and environmental disasters. Fishing is the primary source of food and income for individuals in this community. Previous research in Bodo City found elevated metal levels in fish. Toenails were used as a biomarker to investigate the feasibility for use in risk assessment studies in developing countries. The toenails collected had significantly higher manganese levels (median 5.8 µg/g) and lead levels (median 0.98 µg/g) than those reported in more developed countries, comparable levels to those from other low-middle incomes countries. These exposure levels are likely a direct result of exposures from the environmental disasters the community has experienced and would be related to increased risks for many diseases previously associated with heavy metal exposures.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Metais Pesados/metabolismo , Unhas/química , Poluentes Químicos da Água/metabolismo , Biomarcadores , Monitoramento Ambiental , Contaminação de Alimentos , Humanos , Chumbo , Manganês/análise , Metais Pesados/análise , Nigéria , Poluição por Petróleo , Alimentos Marinhos , Poluentes Químicos da Água/análise
12.
Talanta ; 208: 120429, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816786

RESUMO

Rapid industrialization has resulted in a progressive increase in human exposure to hazardous chemicals. The present work develops and validates a new method to determinate 18 endocrine disrupting chemicals (EDCs) in human nail samples. In contrast to other common biological samples, nail sampling is non-invasive and since they take several months to grow out, they are well suited for measuring and reflecting the cumulative exposure to harmful substances in the long term. A digestion of samples with a 0.04 M solution of sodium hydroxide is carried out followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), working in multiple-reaction-monitoring (MRM) mode. The compounds were separated in 8 min. Multivariate optimization strategies were used for the optimization of the parameters that affects the digestion procedure. The validation was developed using a matrix-matched calibration and a recovery assay with spiked samples. The limits of detection and quantification ranged from 0.3 to 1.2 ng g-1 and from 1 to 5 ng g-1, respectively. Recovery rates for spiked samples were between 88% and 113% and the relative standard deviation (% RSD) was lower than 12.7% for all studied EDCs. The method was applied for the analysis of these compounds in human nail samples from volunteers. All samples tested positive for several of the analyzed EDCs.


Assuntos
Disruptores Endócrinos/análise , Unhas/química , Adulto , Compostos Benzidrílicos/análise , Monitoramento Biológico , Carbanilidas/análise , Criança , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Fluorcarbonetos/análise , Humanos , Masculino , Parabenos/análise , Fenóis/análise , Espectrometria de Massas em Tandem/métodos
13.
J Trace Elem Med Biol ; 57: 1-8, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31541876

RESUMO

INTRODUCTION: A greater prevalence of dental fluorosis has been reported in higher- versus lower-altitude communities. This study, for the first time, examined several aspects of fluoride metabolism in children, aged 4-5 years, and their parent, living at lower altitude (<78 m) and higher altitude (>1487) areas in Nepal. METHODS: The study assessed total daily fluoride intake (TDFI), 24 h urinary fluoride excretion (UFE), and fluoride concentrations of toe- and finger-nail (FCtoenail, FCfingernail) in children and parents as well as fluoride concentration of plasma (FCplasma) in parents. Fractional urinary fluoride excretion (FUFE) was calculated as the ratio between UFE and TDFI. FCtoenail, FCfingernail and FCplasma were normalised for TDFI by dividing the variables by TDFI and the ratio was reported as the percentage. RESULTS: In total, 89 children and 80 parents took part in the study: 42 children and 41 parents from the lower altitude area; 47 children and 39 parents from the higher altitude area. Fluoride concentration of drinking water was significantly (P < 0.001) higher at lower altitude (0.395 mg F/l) than at higher altitude (0.104 mg F/l). TDFI was significantly (p < 0.001) higher in both children and parents living in lower altitude than those living at higher altitude. There was a statistically significant (p = 0.044) difference in the mean FUFE of children living at lower altitude (53%) and higher altitude (46%). However, no significant difference in FUFE was found between parents living at lower altitude (47%) compared with higher altitude (41%). In both children and parents, no statistically significant differences in normalised FCtoenail, FCfingernail were found between the two altitude areas. However, normalised FCplasma was statistically significantly (P = 0.005) higher in parents living at higher altitude (0.15%) compared with those living at lower altitude (0.11%). CONCLUSION: The results suggest that higher altitude living results in decreased urinary fluoride excretion, and consequently increased fluoride retention in children for a given dose (amount) of fluoride.


Assuntos
Altitude , Fluoretos/sangue , Fluoretos/urina , Unhas/química , Pré-Escolar , Água Potável/análise , Feminino , Fluoretos/análise , Humanos , Masculino , Nepal
14.
Forensic Sci Int ; 305: 110031, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31707238

RESUMO

A rectrospective study was conducted on the effect of the long term storage of 122 DNA samples resuspended in water, one of the elution media still suggested by well established protocols. These DNA samples come from four different kinds of forensically relevant samples (saliva swabs, FTA card bloodstains, nails and II° World War bones) extracted in 2008-2018 and stored at - 20°C (n=113 of groups #1-#5) and at +4°C (n=9 of the group #6), respectively. At the time of the present study (2019), quantitative PCR (qPCR) was employed as tool for assessing the degradation of the samples. The employment of the Human Quantifiler Kit showed that the median loss of DNA ranged from 17.8% to 66.6% in groups #1-#5 while it was 85.0% in group #6. However, it is likely that these values represent an underestimation due to the shortness of the qPCR probe (62 bp). Noteworthy, the DNA loss was statistically significant in each of the six groups (p values ≤ 0.0167). Thus, in agreement with the data on spontaneous DNA decay, no forensic DNA sample should be stored in water for long term periods. In conclusion, the results of this technical note warn against the use of water for this purpose.


Assuntos
Degradação Necrótica do DNA , DNA/análise , Preservação Biológica/métodos , Manejo de Espécimes/métodos , Água , Osso e Ossos/química , Humanos , Unhas/química , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Saliva/química , Temperatura , Fatores de Tempo
15.
Environ Int ; 133(Pt B): 105227, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31639601

RESUMO

In this study, the occurrence of 8 polybrominated diphenyl ethers (PBDEs), 5 alternative flame retardants (AFRs), and 7 organophosphate flame retardants (OPFRs) was determined in 50 pairs of human fingernail and indoor dust samples. The concentrations in fingernail were 9.79-242 ng/g, 17.7-926 ng/g, and 58.0-590 ng/g for PBDEs, AFRs, and OPFRs. Male fingernail showed significantly (p < 0.05) higher Σ8PBDE concentrations than female fingernails, while no significant gender differences were observed for AFRs and OPFRs. Lower ratios of BDE209 to Σ8PBDE and DBDPE to Σ5AFRs were found in fingernails than in dust. Due to their relatively rapid in vivo debromination, BDE 209 and DBDPE in fingernails were most likely from external sources rather than internal exposure (such as through blood circulation). Similar composition profiles between fingernail and dust were observed for PBDEs (excluding BDE209), AFRs (excluding DBDPE), and OPFRs, indicating that indoor dust may be a significant source for these FRs in human fingernails. Significant correlations between fingernail and dust were observed for BDE 47 (p < 0.01; r = 0.50), TBPH (p < 0.01; r = 0.37) and TBOEP (p < 0.01; r = 0.53). Results in this study provided information about contamination levels and exposure sources of FRs, which is important for long-term biomonitoring and health risk assessment of FRs.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Retardadores de Chama/análise , Unhas/química , Feminino , Humanos , Masculino
16.
Artigo em Inglês | MEDLINE | ID: mdl-31614844

RESUMO

There is limited evidence on the distribution of heavy metals and its association with secondhand smoking (SHS) within Pacific Island children living in New Zealand. Certain heavy metals such as cadmium (Cd), lead (Pb), and aluminum (Al) bioaccumulates in the body and can deteriorate health in both children and adults. Others, such as chromium (Cr) and nickel (Ni) in trace amounts are necessary but become toxic at high levels. Exposure routes of these elements include food, water, and air. The purpose of this study was to identify the distribution of toxic metal concentrations and its possible correlation with SHS within the Pacific Island children. A sub-sample of children within Pacific Island families longitudinal study, at the nine-year phase, who were living in the New Zealand city of Auckland were invited to participate, (n = 278). Toenails were used as a biomarker to determine Cr, Pb, Cd, Cu, Ni, and Al concentration using inductively coupled plasma mass spectrometry. Reliable and validated questionnaires were used for demographics, lifestyle, and health outcome variables. Significant differences between household smoking status and ethnicity, as well as parents' marital status, were observed (p < 0.05). There was no statistical difference in heavy metal concentrations in smoking versus non-smoking households. However, Cr, Pb, Cd, Cu, and Ni concentrations were all higher than the required optimal health value in both groups. A high concentration of heavy metals was observed in these children that exceeded the value required for optimal health, although no significant difference in heavy metals with regards to secondhand smoking was observed. SHS was associated with children's ethnicity and parental marital status, but not with household income levels or maternal education.


Assuntos
Biomarcadores/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Unhas/química , Poluição por Fumaça de Tabaco/análise , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Dedos do Pé , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Nova Zelândia , Ilhas do Pacífico
17.
Environ Res ; 179(Pt A): 108787, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31610392

RESUMO

Health problems associated with essential trace metals can result from both inadequate (i.e., low intake) and excessive exposures (i.e., from environmental and/or occupational source). Thus, measuring the exposure level is a real challenge for epidemiologists. Among non-invasive biomarkers that intend to measure long-term exposure to essential trace metals, the toenail is probably the biological matrix with the greatest potential. This systematic review collects the current evidence regarding the validity of toenail clippings as exposure biomarker for trace metals such as boron, cobalt, copper, iron, manganese, molybdenum, selenium, silicon, vanadium and zinc. Special attention was paid to the time-window of exposure reflected by the toenail, the intraindividual variability in exposure levels over time in this matrix, and the relationship of toenail with other biomarkers, personal characteristics and environmental sources. Our search identified 139 papers, with selenium and zinc being the most studied elements. The variability among studies suggests that toenail levels may reflect different degrees of exposure and probably correspond to exposures occurred 3-12 months before sampling (i.e., for manganese/selenium). Few studies assessed the reproducibility of results over time and, for samples obtained 1-6 years apart, the correlation coefficient were between 0.26 and 0.66. Trace metal levels in toenails did not correlate well with those in the blood and urine and showed low-moderate correlation with those in the hair and fingernails. Available data suggests that for some elements (Se, Mn, Zn) toenail concentrations reflect long-term external exposures in fairly reproducible levels, while for other metals, this association has not yet been assessed. Among dietary factors, only toenail selenium showed clear associations with the intake of supplements or specific foods. The toenail levels could also represent occupational exposure, for instance, Mn exposure in welders. The scarcity of information on other essential trace elements, together with the great heterogeneity among studies makes the validation of the usage of toenails as biomarkers of exposure to these elements difficult. Standardization of sample collection, quality control, analytical techniques and reporting procedures might facilitate further research focused on the clear understanding of the significance of essential levels in this promising matrix and would enhance its utility in epidemiological research.


Assuntos
Exposição Ambiental/análise , Metais , Unhas/química , Biomarcadores/química , Exposição Ambiental/estatística & dados numéricos , Humanos , Reprodutibilidade dos Testes , Selênio , Oligoelementos
18.
Environ Monit Assess ; 191(9): 530, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31372746

RESUMO

Activities in the Bangladeshi leather industries have the potential to cause chemical pollutions thereby deteriorating the working environments, the surrounding residential areas, or even foodstuffs. Therefore, it is important to determine the chemical exposures among the industry workers and residents of the surrounding areas who may be directly or indirectly impacted by the contaminated environment. This study focused on evaluating the hazard arising from exposure to metals due to industrial contamination. Tissue samples of hair and nails were collected from both the leather industry workers and residents in the vicinity of the industries. Using chromium as an indicator of contamination/exposure from the leather industry, it was the most significant metal contaminant for industry workers ranging from 21.85 to 483 mg/kg and for industry-neighboring residents at 6.01 to 296.16 mg/kg. Both the workers and neighboring residents were found to be excessively exposed (P < 0.05) to chromium compared with the investigated control group of people living in a distant village area which had no industrial establishments.


Assuntos
Monitoramento Ambiental , Poluição Ambiental , Intoxicação por Metais Pesados , Metais Pesados/toxicidade , Exposição Ocupacional , Bangladesh , Cromo/análise , Cabelo/química , Humanos , Indústrias , Metais Pesados/análise , Unhas/química
19.
Appl Spectrosc ; 73(12): 1436-1450, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31411494

RESUMO

A novel method based on the Vancouver Raman algorithm (VRA) and empirical mode decomposition (EMD) for denoising Raman spectra of biological samples is presented. The VRA is one of the most used methods for denoising Raman spectroscopy and is composed of two main steps: signal filtering and polynomial fitting. However, the signal filtering step consists in a simple mean filter that could eliminate spectrum peaks with small intensities or merge relatively close spectrum peaks into one single peak. Thus, the result is often sensitive to the order of the mean filter, so the user must choose it carefully to obtain the expected result; this introduces subjectivity in the process. To overcome these disadvantages, we propose a new algorithm, namely the modified-VRA (mVRA) with the following improvements: (1) to replace the mean filter step by EMD as an adaptive parameter-free signal processing method; and (2) to automate the selection of polynomial degree. The denoising capabilities of VRA, EMD, and mVRA were compared in Raman spectra of artificial data based on Teflon material, synthetic material obtained from vitamin E and paracetamol, and biological material of human nails and mouse brain. The correlation coefficient (ρ) was used to compare the performance of the methods. For the artificial Raman spectra, the denoised signal obtained by mVRA (ρ>0.91) outperforms VRA (ρ>0.86) for moderate to high noise levels whereas mVRA outperformed EMD (ρ>0.90) for high noise levels. On the other hand, when it comes to modeling the underlying fluorescence signal of the samples (i.e., the baseline trend), the proposed method mVRA showed consistent results (ρ>0.94). For Raman spectra of synthetic material, good performance of the three methods (ρ=0.99 for VRA, ρ=0.93 for EMD, and ρ=0.99 for mVRA) was obtained. Finally, in the biological material, mVRA and VRA showed similar results (ρ=0.96 for VRA, ρ=0.85 for EMD, and ρ=0.91 for mVRA); however, mVRA retains valuable information corresponding to relevant Raman peaks with small amplitude. Thus, the application of EMD as a filter in the VRA method provides a good alternative for denoising biological Raman spectra, since the information of the Raman peaks is conserved and parameter tuning is not required. Simultaneously, EMD allows the baseline correction to be automated.


Assuntos
Acetaminofen/química , Encéfalo/ultraestrutura , Unhas/química , Análise Espectral Raman/métodos , Vitamina E/química , Algoritmos , Animais , Humanos , Camundongos , Unhas/ultraestrutura , Politetrafluoretileno/química , Processamento de Sinais Assistido por Computador , Manejo de Espécimes
20.
Sci Rep ; 9(1): 10861, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31350461

RESUMO

Methylmercury (MeHg) is an environmental neurotoxin with human exposure mainly from dietary intake of contaminated fish. Exposure to MeHg has been implicated in neurological damage, but research on its role in cancers, specifically glioma, is limited. In a glioma case-control study, we examined associations between toenail mercury (Hg) and glioma risk. We also examined genetic polymorphisms in 13 genes related to MeHg metabolism for association with glioma risk; genetic associations were also studied in the UK Biobank cohort. Median toenail Hg in cases and controls, respectively, was 0.066 µg/g and 0.069 µg/g (interquartile range (IQR): 0.032-0.161 and 0.031-0.150 µg/g). Toenail Hg was not found to be significantly associated with glioma risk (Odds Ratio: 1.02; 95% Confidence Interval: 0.91, 1.14; p = 0.70 in analysis for ordinal trend with increasing quartile of toenail MeHg). No genetic variant was statistically significant in both of the studies; one variant, rs11859163 (MMP2) had a combined p-value of 0.02 though it was no longer significant after adjustment for multiple testing (Bonferroni corrected p = 1). This study does not support the hypothesis that exposure to MeHg plays a role in the development of glioma at levels of exposure found in this study population.


Assuntos
Neoplasias Encefálicas/epidemiologia , Glioma/epidemiologia , Metaloproteinase 2 da Matriz/genética , Mercúrio/análise , Compostos de Metilmercúrio/metabolismo , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Exposição Dietética , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Compostos de Metilmercúrio/análise , Pessoa de Meia-Idade , Unhas/química , Estudos Prospectivos , Fatores de Risco , Reino Unido/epidemiologia , Estados Unidos/epidemiologia , Adulto Jovem
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