RESUMO
An increase in policy ambition is needed to close the gaps related to climate change mitigation and those required to meet the targets of Paris Agreement. This article examines the contemporary situation of carbon pricing and suggests how carbon costs would help countries adopt comprehensive climate policies. This paper explores the carbon pricing imitative across different regions and the associated issues and proposes how to format holistic, ambitious approaches for effective implementation of carbon pricing. The carbon taxes and emission trading programs are the primary tools for implementation costs. Carbon taxes, fuel taxes, subsidies for fossil energy, and emission trading systems (ETSs) all contribute to these costs. Different countries have adopted different approaches to adopt and mitigate the adverse effect of carbon emissions, but coordinated and integrated efforts are needed. This paper emphasizes the effective carbon pricing and integrating role of finance departments in climate policy; new synergies can be developed to boost government agencies' ability to implement climate policy. Governments may increase their involvement in carbon pricing beyond direct carbon pricing if they implement efficient carbon pricing. Governments, international organizations, and civil society can all play a role in pushing for effective carbon prices to encourage more ambitious targets. Furthermore, the article stresses the need for open communication and a proper understanding of carbon pricing potential to implement climate policy.
Assuntos
Carbono , Mudança Climática , Custos e Análise de CustoRESUMO
A green vortex assisted based liquid-liquid microextraction (VA-LLME) method was developed for preconcentration of selenium. Ammonium pyrrolidine dithiocarbamate (APDC) was used to form a hydrophobic complex with selenium in natural water, agricultural soil and food samples by GFAAS. Whereas Triton X-114, a nonionic surfactant and 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid were used for Se extraction as a dispersing medium. The conical flasks contents were shack on a vortex mixer to increase the extraction efficiency. Multivariate techniques were used to evaluate extraction parameters; pH, vortex time, APDC amount, volume of ionic liquid and Triton X-114 and centrifugation rate on the recovery of Se. The central composite design (CCD) was used for further optimization of the essential extraction parameters. The enhancement factor and limit of detection were obtained as 98.7 and 0.07⯵gâ¯L-1. The certified reference materials was used for accuracy of method and the related standard deviation was found to be 3.51%. The resulted data indicated that concentrations of Se in all types of water samples were below the permissible limit recommended by WHO.
Assuntos
Agricultura , Microextração em Fase Líquida/métodos , Selênio/análise , Selênio/isolamento & purificação , Solo/química , Água/química , Imidazóis/química , Líquidos Iônicos/química , Limite de Detecção , Análise Multivariada , Octoxinol/química , Polietilenoglicóis/química , Pirrolidinas/química , Tiocarbamatos/químicaRESUMO
The causes of night blindness in children are multifactorial and particular consideration has been given to childhood nutritional deficiency, which is the most common problem found in underdeveloped countries. Such deficiency can result in physiological and pathological processes that in turn influence biological sample composition. This study was designed to compare the levels of selenium (Se) and mercury (Hg) in scalp hair, blood, and urine of night blindness children age ranged (3-7) and (8-12) years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure was developed as a sample pretreatment for the determination of Se and Hg in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood, and urine. The Se and Hg in biological samples were measured by electrothermal atomic absorption spectrometry and cold vapor atomic absorption spectrometry, prior to microwave acid digestion, respectively. The concentration of Se was decreased in scalp hair and blood samples of male and female night blindness children while Hg was higher in all biological samples as compared to referent subjects. The Se concentration was inversely associated with the risk of night blindness in both genders. These results add to an increasing body of evidence that Se is a protecting element for night blindness. These data present guidance to clinicians and other professional investigating deficiency of essential micronutrients in biological samples (scalp hair and blood) of night blindness children.
Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Mercúrio/metabolismo , Cegueira Noturna/metabolismo , Selênio/metabolismo , Ácidos , Criança , Pré-Escolar , Exposição Ambiental/análise , Monitoramento Ambiental , Feminino , Cabelo/química , Humanos , Masculino , Mercúrio/análise , Selênio/análise , Espectrofotometria AtômicaRESUMO
The abnormal metabolism of metal ions plays an important role in health and disease conditions; hence, the studies about them have received much interest. The objective of this study was to evaluate the association between trace and toxic elements zinc (Zn), cadmium (Cd), selenium (Se), and mercury (Hg) in biological samples (scalp hair, blood, and urine) of hypertensive patients (n = 257), residents of Hyderabad, Pakistan. For comparison purpose, the biological samples of age-matched healthy controls were selected as referents. The concentrations of trace and toxic elements were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using certified reference materials and by the conventional wet acid digestion method. The recovery of all studied elements was found in the range of 96.4-99.1 % in certified reference materials. The results of this study showed that the mean values of Cd and Hg were significantly higher in scalp hair, blood, and urine samples of hypertensive patients than in referents (P < 0.001), whilst the concentrations of Zn and Se were lower in the scalp hair and blood, but higher in the urine samples of hypertensive patients. The deficiency of Zn and Se and the high exposure of toxic metals may be synergistic with risk factors associated with hypertension.