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1.
Environ Pollut ; 344: 123447, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38278401

RESUMO

Environmental phenolic chemicals, due to their widespread occurrence and potent estrogenic properties, pose a risk to human exposure. The phenolic organic contaminants alkylphenols (APs) and alkylphenol polyethoxylates (APEs) are used in various household applications, and they may enter to the environment during production and use, potentially appearing in indoor dust. However, little is known about the levels of environmental phenolics in indoor environments. In this study, five of these compounds namely octylphenol (OP), 4-Octylphenol Monoethoxylate (4-OPME), 4-tert-octylphenol (4-t-OP), 4-n-nonylphenol (4-n-NP) and nonylphenol diethoxylate (di-NPE) were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in household dust samples (n = 148) collected from Ankara, the capital of Turkiye. OP and 4-OPME was not present in any of the analyzed samples. The median concentrations of the 148 settling dust samples were 35, 520, and 1910 ng g-1 dust for 4-t-OP, 4-n-NP, and di-NPE, respectively. An assessment of the human (children and adults) exposure pathway to APs and APEs, which are recognized as endocrine-disrupting chemicals found in residential dust, revealed that it was approximately 3 times higher for children than for adults at both moderate and heavy exposure levels. The association between chemical exposure, house characteristics, and family lifestyle was investigated using a multivariate logistic regression model. According to the results of this model, while the high concentrations measured for 4-t-OP were not found to be associated with any of the household parameters, high levels of 4-n-NP and di-NPE were associated with the frequency of house cleaning, repairs made during the previous year, residential type, the number of occupants, flooring materials, and the purchase of new household items within the past year. This study provides a basis for prioritizing toxicology and exposure studies for EDCs and mixtures and may offer new tools for exposure assessment in health studies.


Assuntos
Poeira , Hominidae , Fenóis , Adulto , Criança , Humanos , Animais , Cromatografia Líquida , Turquia , Espectrometria de Massas em Tandem
2.
Environ Sci Pollut Res Int ; 30(47): 103690-103702, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37688698

RESUMO

Microplastics (MPs), affecting aquatic and terrestrial ecosystems, have spread globally. The atmosphere is known as a pollutant acceptor and carrier among other ecosystems. However, the fate and amount of microplastics in the atmosphere have been the subject of less research. Therefore, it is quite important to study the amount and properties of microplastics in atmospheric fallout. The main purpose of this article is to discover microplastics in fresh snow samples collected in three different regions of Ankara and to identify potential sources of supply. The morphologies and compositions of microplastics were analyzed and characterized using scanning electron microscopy (SEM/EDS). µ-Raman spectroscopy was used to reveal the various polymer types of the selected samples. As a result, microplastics were found in all snow samples. Among the nine snow samples examined, 537 particles were recognized as MPs. The average abundance of MPs in snow samples was 59.66 items L-1. Fibers, fragments, films, and circular forms were found in all snow samples. Fragments predominated for all samples (50.08%), followed by films (28.54%), fibers (16.86%), and circulars (4.50%). The proportion of small plastics was quite high when compared to the large plastics captured by snow. Smaller MP particles found in the snow had more variety, suggesting that the microplastics in the snow samples have been broken down by long-range transport and deposition. Six different polymer types were discovered in the snow samples in this study. The most frequently identified polymer was polyethylene (31%), succedded by polystyrene (28%), and polypropylene (21%). Polyethylene terephthalate (12%), polyvinyl chloride (5%), and nylon were present in smaller proportions.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Turquia , Ecossistema , Neve , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polímeros
3.
Environ Sci Pollut Res Int ; 30(3): 7718-7735, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36044148

RESUMO

One of the impacts of the COVID-19 pandemic is leading people remain at homes longer than ever. Considering the elongation of the time people spend indoors, the potential health risks caused by contaminants including heavy metals in indoor environments have become even more critical. The purpose of this study was to evaluate the levels and sources of heavy metals in indoor dust, to assess the exposure to heavy metals via indoor dust, and to estimate the associated health risk. The highest median value was measured for Zn (263 µg g-1), while the lowest median concentration value was observed for Cd (0.348 µg g-1). The levels of elements measured in the current study were found to be within the ranges reported in the other parts of the world, mostly close to the lower end of the range. House characteristics such as proximity to the main street, presence of pets, number of occupants, and age of the building were the house characteristics influencing the observed higher concentrations of certain heavy metals in houses. Enrichment factor values range between 1.79 (Cr) and 20.4 (Zn) with an average EF value of 8.80 ± 6.80 representing that the targeted elements are enriched (EF>2) in indoor dust in Ankara. Positive matrix factorization results showed that the heavy metals in the house dust in the study area are mainly contributed from sources namely outdoor dust, carpets/furniture, solders, wall paint/coal combustion, and cigarette smoke. Carcinogenic and non-carcinogenic risk values from heavy metals did not exceed the safe limits recommended by EPA. The highest carcinogenic risk level was caused by Cr. The risk through ingestion was higher than inhalation, and the risk levels were higher for children than for adults.


Assuntos
COVID-19 , Metais Pesados , Oligoelementos , Criança , Adulto , Humanos , Poeira/análise , Monitoramento Ambiental/métodos , Turquia , Pandemias , Medição de Risco , Metais Pesados/análise , Carcinogênese , China , Cidades
4.
Restor Dent Endod ; 38(3): 141-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24010080

RESUMO

OBJECTIVES: Assessment of dental pain severity is very challenging in dentistry. Previous studies have suggested that elevated salivary alpha amylase may contribute to increased physical stresses. There is a close association between salivary alpha amylase and plasma norepinephrine under stressful physical conditions. The aim of this study was to evaluate the relationship between pain severity and salivary alpha amylase levels in patients with symptomatic irreversible pulpitis. MATERIALS AND METHODS: Thirty-six patients (20 females and 16 males) with severe tooth pain due to symptomatic irreversible pulpitis were selected. The visual analogue scale (VAS) score was used to assess the pain severity in each patient. Unstimulated whole saliva was collected, and the level of alpha amylase activity was assessed by the spectrophotometric method. Statistical analysis was performed using SPSS 13. RESULTS: The level of alpha amylase was significantly increased in the saliva in association with pain severity assessed by VAS. The salivary alpha amylase was also elevated with increased age and in males. CONCLUSIONS: There was a significant correlation between the VAS pain scale and salivary alpha amylase level, which indicates this biomarker may be a good index for the objective assessment of pain intensity.

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