In this work, a procedure for preconcentration of silver using dispersive liquid–liquid microextraction with the reagent dithizone as complexing reagent was developed. At pH 2, silver ions are complexed with dithizone and extracted into the fine droplets formed when mixing carbon tetrachloride (extraction solvent), ethanol (disperser solvent) and the sample solution. After extraction, the phase...

INTRODUCTION While NTM infection is mainly acquired from environmental exposure, monitoring of environmental niches for NTM is not a routine practice. This study aimed to find the prevalence of environmental NTM in soil and water in four highly populated suburbs of Tehran, Iran. MATERIAL AND METHODS A total of 4014 samples from soil and water resources were collected and studied. Sediments of...

We report a novel molecular assay, based on helicase-dependent amplification (HDA), for the detection of enterococci as markers for fecal pollution in water. This isothermal assay targets the same Enterococcus 23S rRNA gene region as the existing quantitative polymerase chain reaction (qPCR) assays of U.S. Environmental Protection Agency Methods 1611 and 1609 but can be entirely performed on a ...

This study aims at providing recommendations concerning the validation of analytical protocols by using routine samples. It is intended to provide a case-study on how to validate the analytical methods in different environmental matrices. In order to analyze the selected compounds (pesticides and polychlorinated biphenyls) in two different environmental matrices, the current work has performed ...

Human health is closely related with the quality of drinking water. Various chemical pollutants in the drinking water can cause great risk to human health. Shizuishan city is an important coal-based industrial city where residents mainly rely on groundwater. In order to protect the safety of water supply, based on the sample survey, health risk assessment model recommended by the Unites States ...

In this novel study, some factors that affect the enrichment efficiency of multi-walled carbon nanotubes (MWCNTs) towards some pesticides in environmental water samples were studied. The effect of oxidation of MWCNTs with various oxidizing agents and the effect of length and external diameter of MWCNTs were investigated. Model pesticides were selected from various common categories of pesticide...

Early detection of water blooms caused by potential toxin-producing cyanobacteria is important in environmental monitoring. We present a new nucleic acid-based method for detection of cyanobacteria in water that utilizes the same paramagnetic solid phase (beads) for both bacterial cell concentration and subsequent DNA purification. In the cell concentration step, the beads were attracted to a m...

Scarcity of water in the world, virtually, has two sources: the quality and the quantity made available for populations. In the area covered by this study, the selected municipalities from the river basins 3 e 4 of the Paranapanema River and from the basin of the Pirapó River, availability is always greater than the demand and the environmental problems are more often linked to the quality than...

Some molecular methods for tracking fecal pollution in environmental waters have both PCR and quantitative PCR (qPCR) assays available for use. To assist managers in deciding whether to implement newer qPCR techniques in routine monitoring programs, we compared detection limits (LODs) and costs of PCR and qPCR assays with identical targets that are relevant to beach water quality assessment. Fo...

A novel sorbent for magnetic solid-phase extraction, 1,4,7,10-tetrabenzyl-1,4,7,10-tetraazacyclododecane (TBCD) modified magnetic nanoparticles, was synthesized in this work. The four benzyl groups of TBCD provide the Fe3O4-TBCD nanoparticles with strong adsorption capacity for polycyclic aromatic hydrocarbons (PAHs) due to their π-π stacking interaction, which increases selectivity of the synt...