Editing Arsenic poisoning (section)

== Legislation ==
In the U.S. in 1975, under the authority of the Safe Drinking Water Act, the U.S. Environmental Protection Agency determined the National Interim Primary Drinking Water Regulation levels of arsenic (inorganic contaminant – IOCs) to be 0.05&nbsp;mg/L (50 parts per billion – ppb).<ref name=":2">{{cite web|url=https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P1009V6R.txt|title=United States Environmental Protection Agency. State Implementation Guidance for the Arsenic Rules}}</ref>

Throughout the years, many studies reported dose-dependent effects of arsenic in drinking water and skin cancer. In order to prevent new cases and death from cancerous and non-cancerous diseases, the Safe Drinking Water Act directed the Environmental Protection Agency to revise arsenic's levels and specified the maximum contaminant level (MCL). MCLs are set as close to the health goals as possible, considering cost, benefits and the ability of public water systems to detect and remove contaminants using suitable treatment technologies.<ref name=":2" /><ref>{{cite web|url=https://www.epa.gov/dwreginfo/chemical-contaminant-rules|title=Chemical Contaminant Rules|website=US Environmental Protection Agency|language=en|access-date=2018-03-29|date=2015-10-13}}</ref>

In 2001, Environmental Protection Agency adopted a lower standard of MCL 0.01&nbsp;mg/L (10 ppb) for arsenic in drinking water that applies to both community water systems and non-transient non-community water systems.<ref name=":2" />

In some other countries, when developing national drinking water standards based on the guideline values, it is necessary to take account of a variety of geographical, socio-economic, dietary and other conditions affecting potential exposure. These factors lead to national standards that differ appreciably from the guideline values. That is the case in countries such as India and Bangladesh, where the permissible limit of arsenic in absence of an alternative source of water is 0.05&nbsp;mg/L.<ref name=":0">{{cite web|url=https://www.who.int/water_sanitation_health/dwq/arsenicun5.pdf|publisher=World Health Organization (WHO)|title=Chapter 5: Drinking Water Guidelines and Standards}}</ref><ref>{{cite web|url=http://www.searo.who.int/india/topics/arsenic/en/|title=Arsenic|website=South-East Asia Regional Office|language=en-GB|access-date=2018-03-29}}</ref>

=== Challenges to implementation ===

Arsenic removal technologies are traditional treatment processes which have been tailored to improve removal of arsenic from drinking water. Although some of the removal processes, such as precipitative processes, adsorption processes, ion exchange processes, and separation (membrane) processes, may be technically feasible, their cost may be prohibitive.<ref name=":2" />

For underdeveloped countries, the challenge is finding the means to fund such technologies. The Environmental Protection Agency, for example, has estimated the total national annualized cost of treatment, monitoring, reporting, record keeping, and administration to enforce the MCL rule to be approximately $181 million. Most of the cost is due to the installation and operation of the treatment technologies needed to reduce arsenic in public water systems.<ref>{{cite web|url=https://nepis.epa.gov/Exe/ZyPdf.cgi?Dockey=20001XXE.txt|title=United States Environment Protection Agency. Technical Fact Sheet: Final Rule for Arsenic in Drinking Water}}</ref>