| Popis: |
This paper first reviews the arsenic nature, and its mobilization in environment. Arsenic is a significant element of earth crust and also in a human body. General sources of arsenic are air, food, cigarette smoke and beverages. Being soluble in water it exists in ionic forms and affects the humans who consume arsenic contaminated water. Its effects are severe and long lasting. Pakistan is one of those countries where most of the ground water is contaminated with arsenic. Different organizations such as World Health Organization, International Agency for Research in Oncology & International Agency for Research in Cancer and the United States Environmental Protection Agency has set up the maximum permissible value of arsenic in drinking water for various countries. IARC has ranked arsenic a group 1 human carcinogen which causes lung, bladder and urinary cancers. In Punjab (Pakistan) 20% of population is exposed to over 10 g/L in drinking water and 3% of population is exposed to over 50 g/L and in Sindh 36% of population is exposed to arsenic via drinking water. In Punjab and Sindh drinking water is contaminated with arsenic above the permissible value defined by World Health Organization (WHO), while KPK is less affected. Baluchistan is almost safe from arsenicism. |
