A survey of the gross alpha radioactivity in drinking water from wells and bore holes in Sokoto city was carried out. Forty samples were drawn at random from locally dug wells and bore holes in Sokoto city, Northern Nigeria. The samples were analyzed using the Eurysis system- eight channel gas filled proportional counter. The result shows that the range of alpha activity varied from 0.01 to 6.00Bq/L, with a geometric mean of 0.26Bq/L. Seventy five percent (75%) and 25% of alpha activity were respectively below and above the USEPA contaminant limit of 0.55Bq/L radioactivity in water. Thirty two and half percent (32.5%) and 67.5% of the alpha activity were respectively below and above the contaminant limit of 0.5Bq/L, as set out by WHO. The gross alpha effective dose was 0.068msv/y (WHO range is 0.04-0.1mSv/y).
Key words: Gross alpha, activity, contaminant limit, Effective dose, geometric mean.
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