Arsenic contaminants drinking water

Arsenic is an ancient and well-known hazard and, along with lead and mercury, is an important environmental contaminant. The inorganic form is far more toxic than organic arsenic, which is commonly found in seafood. Arsenic-contaminated drinking water is a worldwide problem that affects millions of people. Human exposure also occurs from arsenic-treated lumber. 

The earliest known adverse effects associated with chronic arsenic exposure were skin lesions (Yoshida, Yamauchi and Fan Sun, 2004). The effect of arsenic on skin was first noted by several physicians in the late 1800s (Schwartz, 1997). They observed the effects in patients being treated with inorganic arsenic for various aliments. The effect is more widespread in populations that consume arsenic-contaminated drinking water and is related to dose (Yoshida, Yamauchi and Fan Sun, 2004). In southwest Taiwan, the... 

Gold miners had a number of arsenic-associated health problems including excess mortality from cancer of the lung, stomach, and respiratory tract. Miners and schoolchildren in the vicinity of gold mining activities had elevated urine arsenic of 25.7 p,g/L (range 2.2-106.0 p-g/L). Of the total population at this location, 20% showed elevated urine arsenic concentrations associated with future adverse health effects arsenic-contaminated drinking water is the probable causative factor of elevated arsenic in urine. 

Table 1.4. Countries with arsenic-contaminated drinking water (from Tapio and Grosche 2006)...

Singh AL, Singh VK, Srivastava A. Effect of Arsenic contaminated drinking water on human chromosome a case study. Indian J Clin Bio-chem2013 28(4) 422-5. 

For maximum protection of human health from the potential carcinogenic effects of exposure to arsenic through drinking water or contaminated aquatic organisms, the ambient water concentration should be zero, based on the nonthreshold assumption for arsenic. But a zero level may not be attainable. Accordingly, the levels established are those that are estimated to increase cancer risk over a lifetime to only one additional case per 100,000 population. These values are estimated at 0.022 pg As/L for drinking water and 0.175 pg As/L for water containing edible aquatic resources (USEPA 1980 Table 28.7). 

Information on the association of arsenic with skin cancer has primarily involved nonoc-cupational populations exposed to contaminated drinking water. Ingestion of arsenic has also been associated with lung, liver, bladder, and kidney cancers. Dose-response data for these cancers are available from epidemiological studies of a Taiwanese population exposed for 45 years to high levels of arsenic in the drinking water and involving more than 7000 cases of arsenical disease. For water arsenic... 

The toxicity of chronic exposure to arsenic is well established and the best recommendation is to avoid arsenic exposure. The most common home exposure is from contaminated drinking water and arsenic-treated lumber. Certain areas of the country have higher levels of arsenic in water. The EPA has lowered arsenic drinking water standards, but water providers have until 2006 to meet the new standards. Avoid inhalation of sawdust from arsenic-treated lumber or inhalation of smoke from burning arsenic-treated wood. And of course always wash your hands. This is particularly important if a young child is playing on arsenic-treated wood. 

US Environmental Protection Agency (2002). Arsenic Rule Implementation Implementation Guidance for the Arsenic Rule-Drinking Water Regulations for Arsenic and Clarifications for Compliance and New Source Contaminant Monitoring. EPA-816-K-02—018 (available on line at URL http //www.epa.gov/safewater/ars/implement.html). 

Armstrong, C.W., Stroube, R.B., Rubio, T., Siudyla, E.A., Miller, G.B. Outbreak of fatal arsenic poisoning caused by contaminated drinking water. Arch. Environ. Hlth. 1984 39 276-279... 

Arsenic contents measured in sediments are between 0.1 and 490 mg/kg while levels up to 1.5 g/kg were found in coals (average 13 mg/kg). The concentration of arsenic in seawater varies between 0.09 and 24 pg/L (average 1.5 pg/L), and in Ireshwater between 0.15 and 0.45 pg/L (maximum 1 mg/L). In mineral and thermal waters, arsenic was found in concentrations up to a factor of 300 higher than its mean concentration in groundwater [100]. The WHO recommends a maximum contaminant level for arsenic in drinking water 10 pg/L. 

---