Firstly, if you are concerned whether you have any form of arsenic in your drinking water, the best thing is to test for the total amount of arsenic in your water. This is also the case in Pakistan, where previous studies focused on isolated areas. Summary – Arsenic vs Phosphorus. The following is a summary of the results. Arsenic treatment systems are no different. COVID-19 is an emerging, rapidly evolving situation. The percent of community water systems with average concentrations arsenic above the 10 μg/L MCL was 2.3% in 2009-2011 vs. 3.2% in 2006-2008. Arsenic levels above this represent an elevated risk in experiencing illnesses associated with Arsenic poisoning and toxicity. Iron (0.3 and 3 mg/L) and manganese (0.2 mg/L) had little, if any, effect on As III oxidation.