Toxic trace metals in blood of occupationally exposed casual mine workers living in shacks around mining area in Brits, South Africa

摘要

Mineworkers constitute a major workforce in South Africa. Mining activities are known to release varying concentrations of toxic trace metals into the environment depending on the type of mining technology involved. These toxic trace metals could be ingested. inhaled, or absorbed through the dermal part of the human body. The present study evaluated and determined the levels of some selected toxic trace metals in blood of mineworkers working and living in "shacks" (informal houses) directly opposite mining industry. The study employed a mixed method approach. 96 participants (53 occupationally exposed, 23 immediate family members, and 20 participants for the control group) took part in the study. Open-ended questionnaires were used to gather information on health status, gender, and years of employment. Blood samples from the groups were analyzed for trace metal content using inductively coupled plasma mass spectrometry (ICP-MS). The mean blood levels for occupationally exposed mine workers ranged between 0.5 and 6.49 mu g/dL for lead. chromium 0.41 - 13.96 mu g/L. manganese 5.86 - 22.23 mu g/L. cobalt 0.15 - 0.88 +/- 0.05 mu g/L. arsenic 0.33 - 2.19 mu g/L, and cadmium 0.05 - 1.87 g/L. For the nonexposed and control group. the values ranged from 0.5 to 1.84 mu g/dL for lead, chromium 0.41 - 19.01 mu g/L, manganese 6.19 - 22.01 mu g/L, cobalt 0.19 -11.72 mu g/L, arsenic 0.29 - 1.83 mu g/L. and cadmium 0.04 - 1.10 mu g/L. There were significant differences (p < 0.05) in the concentrations of lead. chromium, manganese, cobalt, arsenic, and cadmium within the exposed, nonexposed, and control group. The levels of lead, chromium, manganese, and cadmium in some participants exceeded the permissible limits set by WHO in human blood. Smoking habits of some of the exposed participants in this study have a direct impact on the levels of trace metals in their blood, and there were more smokers in the exposed group compared to the nonexposed and control group. Frequent headache. fatigue, and dizziness were common health issues reported by the mineworkers. Trace metals evaluation is recommended once in 3 months for both miners and their immediate family members living with them in this area.