The activity concentrations of naturally occurring radionuclides ( 238 U, 232 Th and 40 K) were investigated in gold ore mined from Birnin Gwari Artisanal Goldmine in Kaduna state Nigeria using Instrumental Neutron Activation Analysis (INAA) technique. Twelve samples were collected from pits at different depths and the locations of pits were marked out using Global Positioning System (GPS). The measured activity concentration due to 238 U range from 6.18±3.7 to 66.69±4.9 Bq/Kg with mean value 37.36±5.45, Bq/Kg 232 Th range from 16.65±0.8 to 87.29±1.2 Bq/Kg with mean value of 62.69±6.33 and 40 K range from 85.13±4.5 to 1564.69±57.9Bq/Kg with a mean value of 997.52±11 9.97 Bq/Kg. The value compared well with published data from other countries and all values from this study are higher than the world average values and other countries with the exception of 232 Th concentration from India and Malaysia that are slightly higher than the mean value of 232 Th obtained in this study.

Elemental metal pollutants concentration levels and their distribution in soils obtained from farmlands along the bank of river Ngadda and Alau dam in Maiduguri, Borno State, North-East of Nigeria is presented. The study was aimed at determining the levels of contamination of soils with metal pollutants used for fadama farming along the bank of river Ngadda and Alau dam with the objectives of assessing the contamination levels of the soils with metal pollutants from the various farmlands at the various sampled sites of study, and the distribution of the various metal pollutant in the various sampled sites. Soil samples were collected from thirteen different sites on the farmlands along the bank of the river and the dam. The samples were analyzed using Instrumental Neutron Activation Analysis (INAA) and the result obtained indicate that the concentration level of some of the elements determined were above maximum allowable concentration (MAC) value while some below the (MAC) values for example the concentration range for Cr was (16 ± 2 -47 ±3) ppm, Sb was (0.18 ± 0.04 -14.2 ± 7) ppm, Zn was (21.8 ± 4 -145 ± 7) ppm and the maximum Original Research Articlevalues for these ranges exceed the (MAC) value recommended for Agricultural soils while the concentration ranges for As was (0.46 ± 0.12 -1.0 ± 0.2)ppm, Co was (1.6 ± 0.3 -5.3 ± 0.4) ppm, Vn was (14.6 ± 2.32 -29 ± 2) ppm with the maximum value for these ranges being below the MAC values given by some countries. The elements obtained from samples collected from different study areas along the bank of river Ngadda and Alau dam were analyzed for similarity distribution of the study area using mathematical tool of cluster analysis technique employing hierarchical procedure and using WARD's method. The result obtained produce a dendrogram consisting of two clusters comprising of six and seven sites with percentage similarity of 96.5% and 90.8% respectively with one site as an outlier. It is recommended that since some of the trace metals namely Cr, Sb, and Zn assessed in the fadama soils indicates concentrations above the MAC values, they can posed negative health implications to consumers of food which were cultivated on soils from the study area, therefore there is the need to condition the soils before using it for farming so as to make it suitable for food crop farming.

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