Levels of ionizing radiations in selected quarries in Nyamira County, Kenya

Abstract

It has been shown through a survey by World Health Organization and International Commission on Radiological Protection that certain materials (stones) sourced from quarries and used for the building are radioactive. In Kenya, underground stones which are sourced from embedded rocks are used in construction of most of the permanent buildings, yet Kenya has not adequately radio-profiled sources of building materials to determine whether the construction materials contain radionuclides that emit ionizing radiations yet are used for building. Consequently, Kenyans could be at risk of exposure to high levels of ionizing radiations by living in stone houses that are not radio-profiled. Health problems arise due to subjection to ionizing radiations. The study determined the levels of ionizing radiations in sampled quarries in Nyamira County by using Radiological survey dosimeters to show the radiation readings in milliRoentgen/hr then converted to milliSievert per year and the Global Positioning System device took note of the quarries' geographical positions. The study used Minitab version 17.0 software to establish the statistical differences of degree of exposure in sampled quarries. The sample size for the study was 40 quarries. It was revealed that Q-073 and Q-075 both had the lowest radiation readings of 0.64mSv while Q-079 had the highest reading of 3.46mSv equal to a deviation from WHO approved threshold of -35.71%,-36.29% and 245.7%, respectively. The results indicated that 89% of the sampled quarries had radiation emissions above the ICRP and WHO standard. However, within Borabu Sub County, only 5 and within Manga Sub-County 4 of the sampled quarries had radiation readings below ICRP and WHO recommended standards of 1mSv/yr. It was exhibited from the study results that there are higher levels of ionizing radiations in quarries going past recommended standards per year hence causing health risk to quarry workers and general public. Therefore, these results could guide in formation of the national construction policies by including regular surveying for the levels of ionizing radiation in building materials as well as in practicing appropriate mitigation strategies.

Radiological impact of an active quarry in the Papuk Nature Park, Croatia

“… Locations of measurements near Žervanjska quarry ( 1 , 2 , 9 ), near Brenzberg-Točak quarry ( 7 , 8 , 19 , 20 , 21 , 22 , 25 , 26 ), near the road between those quarries ( 3 , 4 , 5 , 6 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ) and near Lake Orahovac ( 23 , 24 ) (Source: Google Maps) …”

“…Quarries are considered a potential source of increased radioactivity, as stone digging can bring material containing increased radioactive content to the surface ( 3 , 4 ). Research into potentially negative radiological impact of quarries has been focused on the exposure of quarry workers to ionising radiation ( 5 , 6 , 7 , 8 ) and on radioactive content analysis of quarry products ( 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ). However, research of radiological effects of a quarry on its surroundings is not common.…”