ASSESSMENT OF ZINC, LEAD AND CADMIUM CONTRIBUTIONS TO DIABETES AND HYPERTENSION: A CASE STUDY OF MARAKWET EAST AND MARAKWET WEST SUB COUNTIES

Abstract

Globally, chronic heavy metal poisoning is of global concern, aggravated by human activities in the world leading to food and drinking water quality issues. This study assessed the relationship between heavy metals and insulin contributing to diabetes and hypertension within Marakwet East and West. A total of thirty six (36) each of water and soil samples from rivers Chepkaitit, Moiben, Embobut, Arror, Mon and Mosongu were purposefully selected. Water samples were collected from each of the three sites of the six rivers during wet and dry seasons. Twelve (12) samples of beef were also collected within the study area. The samples were digested using wet methods to establish levels of Zn, Cd and Pb in water and soil using AAS and in beef samples using ICP-MS. Exploratory research design using a questionnaire was also undertaken for a comparative study of diagnosed diabetic and hypertensive patients. The interaction of the metal divalent cations with insulin was done in neutral and mildly alkaline solutions. Majority (76.5%) of the respondent pointed out that they had heard about heavy metals (χ2 = 31.76, d.f.=2P-value = 0.0001). For hypertension condition, majority of the respondents (45.0%) pointed out that presence of other diseases was the contributing factor to those having the condition. All respondents pointed out that they had been exposed to fertilizers. Few of the subjects responded regarding the issue of health of their family members. There was no significant difference in response pertaining to the type of condition and those who were affected (χ2 = 2.5283 d.f =2, P-Value = 0.2825). For those who were suffering from cancer and hypertension, majority were young women (35.7%) and 43.8%) of the respondents respectively. There was no significant difference in responses concerning how respondents were related to the cancer victims (χ2= 4.57143 d.f =4, P-value = 0.3342) as well as for hypertension (χ2= 9.0, d.f=4, P-value = 0.0611). For diabetes victims, majority (52.2%) were young men while a few were old respondents with a significant difference (χ2= 18.087, d.f =4, P-Value = 0.0012). In water samples, Zn levels were higher during wet season than dry season (p>0.05). Significant increase in Zn levels from upstream (0.212 ppm) to midstream (0.225 ppm) were recorded in water samples (P>0.05). There was significant increase in Cd levels from upstream (0.066 ppm) to midstream (0.068 ppm) (P >0.05). Soil samples collected during wet season from R. Chepkaitit recorded Cd levels of 0.071, 0.078 and 0.053 ppm upstream, midstream and downstream, respectively. Similarly, Pb levels increased from 0.470 ppm to 0.720ppm to 0.791 ppm in water samples correspondingly collected upstream, midstream and downstream of R. Mon. The concentrations of Pb and Cd in some water and soil samples exceeded the WHO standards. The binding strength of Zn, Pb and Cd with histidine resulted in a significant difference (p<0.05) when spiked showing the interaction with histidine. The results from this study would inform the policy decision makers in agriculture and healthcare sectors to sensitize farmers on the use of chemicals and regulate fertiliser applications.