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Welch et al 1988. The standards for arsenic in drinking water have been revised.
Stringent attitude towards the presence of arsenic in water.
Arsenic concentration in potable water. ArsenicIII Lemmo et al 1983. Welch et al 1988. An increase in pH may increase the concentration of dissolved arsenic in water Slooff et al 1990.
ENVIRONMENTAL LEVELS AND HUMAN EXPOSURE 21 Air Arsenic concentrations measured in remote or rural areas range from 002 to 4 ngm3 USNRC 1999. In urban areas arsenic concentrations of 3200 ngm3 have been. The study found that the level of arsenic in potable water is usually above the permissible limit of 001 mgl recommended by Standard Organization of Nigeria SON and World Health Organization.
The permissible level of arsenic in drinking water for Pakistan may be fixed at 005mglitre 50 ppb which is safe enough. Population should be sensitized to use deeper water tables to avoid. As a result these authorities recommended level of maximum arsenic concentration in potable water is 10 μgL and is adopted by the Turkish Ministry of Environment and Forestry.
The health effects of arsenic poisoning vary widely in severity from chronic fatigue to deadly cancers. Symptoms have a latency period of 520 years making early detection difficult. The standards for arsenic in drinking water have been revised.
In Europe through the Directive 9883CE and in the US the new Maximum Contaminant Level is now 10 µgAsL. Fulfilling these new requirements is therefore urgent and it will be a major challenge for the water supply companies as existing technologies are only partly capable of meeting these needs. Modabberi and Moore 2004 found up the arsenic concentration to be 40000μgL in water samples close to the mine benches.
2009 assessed soil and plant samples in six sites in the mining area. They found an arsenic concentration of 6525μgg. The World Health Organization has also recommended acceptable levels of arsenic in drinking water for many years and recently lowered their level to 001 mgL in 1993.
The US subsequently set a more stringent requirement of 001 mgL 10 ppb to protect human health and the environment and compliance was required beginning in January 2006. Long term consumption of water with arsenic concentrations greater than 001 mgL can cause adverse health effects even increasing the risk of cancer. Boiling water for drinking does nothing to reduce the potential effects of arsenic in water rather it increases the concentration.
The highest arsenic removal was obtained in the monopolar series MP-S electrode connection mode for both electrodes as pH 65 for Fe and pH 7 for Al electrodes to achieve a residual arsenic concentration of 10 μgL or less for potable water in the EC process. As the current density increased arsenic removal efficiencies were increased with all types of electrode connection modes. Forms usually exist in potable water in two chemical valence states.
As arsenite As III or arsenate As V. The arsenite species exists in anaerobicanoxic reduced or low oxygen waters as H 3 AsO 3 or H 2 AsO 3 1-. The specific form depends on the pH of the water.
At pH 92 arsenite exists as a 50-50 mixture of H 3 AsO 3 and H 2 AsO 3 1. High iron levels 03 mgL and Low Iron to Arsenic ratio 201. If the iron to arsenic ratio in the source water is less than 201 then a modified treatment process such as coagulationfiltration with the addition of iron salts should be selected.
Section B of Figure 1 Low iron levels 03 mgL. Technologies such as adsorptive media and ion exchange are best suited to sites with relatively low. A colorimetric method for the determination of arsenic III at a concentration of 0002 mg l 1 in potable water was developed.
Stringent attitude towards the presence of arsenic in water. In 1993 the World Health Organization WHO had decreased the maximum contaminant level MCL standard of arsenic in drinking water from 50 to 10 ppb. The drastic reduction of this parametric value has.
Arsenic contamination of ground water is found in many countries throughout the world including the US. The World Health Organization recommends limiting arsenic concentrations in water to 10 μgL although this is often an unattainable goal for many problem areas due to the difficult nature of removing arsenic from water sources. Australia sets the maximum acceptable concentration MAC for Arsenic in drinking water as 7µgL.
While as per Health Canada guidelines the MAC for arsenic is 10µgL. Due to the carcinogenic effects of arsenic we have followed more stringent guidelines in this study. The officially recommended highest levels of arsenic to water concentration is 001 milligrams per litre.
This is a extremely small amount in contrast fluoride has a recommended level of 15mg per litre and chlorine a recommended level of 5mg per litre. Arsenic only becomes dangerous when consumed in high quantities or over prolonged periods. Heating or boiling your water will not remove arsenic.
Because some of the water evaporates during the boiling process the arsenic concentrations can actually increase slightly as the water is boiled. Additionally chlorine bleach disinfection will not remove arsenic. You may wish to consider water treatment methods such as reverse osmosis ultra-filtration distillation or ion exchange.