A novel approach to converting alkylated arsenic to arsenic acid for accurate ICP-OES determination of total arsenic in candidate speciation standards

Versatile dodecyl trimethyl ammonium bromide modified γ-FeOOH for simultaneous removal and determination of As(Ⅴ)

Inorganic arsenic pollution in water spreads all over the world, tremendously threatening environmental safety and human health. Herein, versatile dodecyl trimethyl ammonium bromide modified γ-FeOOH (DTAB-γ-FeOOH) was prepared for sportive removal and visual determination of As(Ⅴ) in water. DTAB-γ-FeOOH displays a nanosheet-like structure with a high specific surface area calculated as 166.88 m² g^-1. Additionally, DTAB-γ-FeOOH shows peroxidase-mimicking feature, which can catalyze colorless TMB to generate blue oxidized TMB (TMBox) in presence of H₂O₂. Removal experiments show that DTAB-γ-FeOOH exhibits good As(Ⅴ) removal efficiency because modification of DTAB makes γ-FeOOH carry abundant positive charges, improving affinity between DTAB-γ-FeOOH and As(Ⅴ). It is found that theoretical maximum adsorption capacity is up to 126.91 mg g^-1. Moreover, DTAB-γ-FeOOH can resist interference of most of co-existing ions. After that, As(Ⅴ) was detected based on peroxidase-like DTAB-γ-FeOOH. As(Ⅴ) can be adsorbed onto DTAB-γ-FeOOH surface, markedly inhibiting its peroxidase-like activity. Based on it, As(Ⅴ) ranging from 1.67 to 3333.33 μg L^-1 can be well detected, with a low LOD (0.84 μg L^-1). The successful sorptive removal and visual determination of As(Ⅴ) from real environmental water indicated that DTAB-γ-FeOOH has great potential in the treatment of As(Ⅴ)-containing environment water.

Determination of total arsenic and hydrophilic arsenic species in seafood

Marine organisms are vital sources of staple and functional food but are also the major dietary route of human exposure to total arsenic. We surveyed the total arsenic content and the mass fractions of hydrophilic arsenic species from five different marine food types cutting across the food chain from microalgae, macroalgae, bivalve clam, crustaceans and finfish. Total arsenic was determined using inductively coupled plasma-mass spectrometry (ICP-MS) while arsenic speciation analysis was performed using high-performance liquid chromatography (HPLC) coupled to ICP-MS as the detector. The total arsenic contents ranged from 133 ± 11 ng/g to 26,630 ± 520 ng/g. The mass fractions of inorganic arsenic (iAs), arsenobetaine (AsB), dimethylarsinic acid (DMA), and the four commonly occurring arsenosugars (AsSugars) are reported. Extractable hydrophilic arsenic species accounted for 10 % (aquacultured shrimp) to 95 % (kelp) of the total arsenic. DMA was established to be a byproduct of the decomposition of AsSugars in acid extracts of samples known to contain these species.

The speciation of inorganic arsenic in soil and vegetables irrigated with treated municipal wastewater

An efficient method using vortex-assisted microextraction based on a deep eutectic solvent followed by graphite furnace atomic absorption spectrometry was developed for the determination of arsenic species in soil and vegetables irrigated with treated wastewater.