Showing 4 results for Arsenic
S Sadr, M Afyuni, N Fathian Por,
Volume 13, Issue 50 (1-2010)
Abstract
Industrial, agricultural and urban activities have contaminated soil by heavy metals that can also increase concentration of the metals in food chains. This study was carried out in Isfahan province where lots of such activities are in progress. The purpose of this study was to determine spatial variability of Arsenic )As) in Isfahan soils. In this research, the soil samples )0-20 cm) were collected in a stratified random sampling system at about 4 Km intervals in a study area of 6800 Km2. The positions of samples were recorded using a GPS. After laboratory preparation, soil samples were measured for total As. Spatial structures of total As were determined by directional variograms. Spherical model was the best model to describe spatial variability of As. Mean-square error )MSE) and correlation coefficient were used to validate variograms. Distribution map for Arsenic was prepared using the obtained information from element by point kriging method and by using Surfer software. Interpolation in blocks by dimensions of 1000×1000 m was made. The mine effective factors with high concentration of As are parent material, and direction of dominant wind has affected the spread of As in north-west of the study area.
S. Shahmoradi, M. Afyuni, M. A. Hajabbasi, A. H. Khoshgoftarmanesh, M. Shirvani,
Volume 19, Issue 71 (6-2015)
Abstract
In this work, the effect of raw and modified bentonite and zeolite with trivalent iron on the stabilization of water-soluble and adsorbed arsenic in a calcareous soil was studied. Raw and modified bentonite and zeolite were added to the soil in different weights in a completely randomized block design with three replications and kept to field capacity soil moisture content of 80% for 8 weeks. The concentrations of water-soluble and adsorbed arsenic, water-soluble and absorbed phosphorus in soil and soil pH were measured. Treatments significantly affected the mobility of arsenic and phosphorus in soil. Raw zeolite and bentonite in different levels increased arsenic mobility (about 107 to 325 % and 259 to 350% respectively). Despite the change in surface properties of zeolites modified with iron, this treatment at different levels increased arsenic mobility in soils by about 124 to 246%. Bentonite modified with iron had the greatest effect on reducing arsenic mobility in soil (about 91%). Phosphate mobility was similar to arsenic in different treatments.
M. Touzandejani, A. Soffianin, N. Mirghafari,
Volume 22, Issue 2 (9-2018)
Abstract
Among the heavy metals, arsenic is known as a carcinogen material and its high concentrations in the ecosystem can be a major concern for public health and environment. The aim of this study was to evaluate the risk map of arsenic contamination and the possibility of its entering into the food chain using the fuzzy method in the central part of the Hamedan-Bahar plain. For this purpose, arsenic concentration in 94 points of groundwater and 49 points of surface soil was analyzed and evaluated in the study area. Soil physico-chemical parameters (clay, organic matter and pH), soil and groundwater contamination probability map, and land use map were selected as the input of this method. In the fuzzy method, two operators (and & or) were used. In order to standardize the parameters, the fuzzy linear function was used. Comparing the classified risk assessment using these operators showed that the results of the operator had the maximum trust. So in areas where concentrations of arsenic in soil and groundwater were high, the physico-chemical parameters such as pH, organic matter and clay content of the soil were low and agriculture products had a high ability to absorb heavy metals and ensure its better to use for the operator.
A. Azough, S. K. Marashi, T. Babaeinejad,
Volume 22, Issue 3 (11-2018)
Abstract
The concern about the war and the threat of terrorism and weapons application and prohibited weapons is growing; on the other hand, the contamination of soil, plant and disease outbreaks in the community is increasing. The main problem with crops, especially wheat in the contaminated soils of war zones, are associated with the high concentrations of heavy metals and toxic things, especially arsenic. Zeolite is one of the solutions to the problem of contaminated soils in war affected areas. The aim of this study was to determine the effect of the ionic strength of zeolite on the adsorption of arsenic and nutritional properties of wheat in contaminated soils including weapons. The experiment was carried out in a factorial arrangement involving a randomized complete design with three replications. Treatments included four levels of zeolite 2.5 (a4), 1.5 (a3), 0.5 (a2), 0 (a1) percent of the weight of the soil and two soil recourses, one obtained from out of the war zone (without contamination) (b1) and other one was from the contaminated soil to weapons (b2). The results showed that soils contaminated by weapons increased the concentrations of arsenic in wheat. Also, with the application of Zeolite in the contaminated soil treatments, there was a significant reduction at 1% level and a remarkable increase in nitrogen, phosphorus, potassium and calcium in the wheat grain in both soils.
