Название | Geochemistry |
---|---|
Автор произведения | Группа авторов |
Жанр | Химия |
Серия | |
Издательство | Химия |
Год выпуска | 0 |
isbn | 9781119710127 |
2 (2) Detailed understanding of the behavior and fate processes of toxic contaminants, including their speciation and partitioning into various phases through mass balance analysis and speciation modelling.
3 (3) Understanding the human toxicology and ecotoxicology of toxic contaminants, including determining key exposure routes, bioavailability and bioaccesibility, and daily intakes using established protocols for human health risk assessment.
4 (4) Comprehensive understanding of the relationship between toxic contaminants and human health outcomes through case-control epidemiological studies, particularly in Africa.
5 (5) Establishing environmental and human health surveillance systems to determine baseline conditions and current status of human and environmental health in serpentinitic geological environments.
1.6 Conclusions
Understanding the nature and human exposure and health risks of toxic geogenic contaminants in serpentinitic ultramafic geological systems is critical for safeguarding human health. The current chapter presented an overview of the nature, occurrence, environmental behavior, and human exposure and health risks associated with toxic geogenic contaminants in serpentinitic ultramafic geological environments. Toxic geogenic contaminants of human health concern include toxic metals, rare earth elements, and chrysotile asbestos. Occupational and non-occupational exposure are the dominant human intake pathways. Human occupational exposure via inhalation occurs in industrial settings such as mining, milling, sculpturing, engraving, and carving. Non-occupational exposure pathways include inhalation of toxic geogenic contaminants and ingestion of contaminated geophagic earths, wild foods, herbal medicines, and water. Weak and poorly enforced occupation and environmental regulations, lack of environmental and human health surveillance systems coupled with high consumption of potentially contaminated wild foods, geophagic earths, and water increase human exposure and health risks in Africa. The prevalence of geophagy and high dietary intake of iron coupled with genetic disposition increases iron overload and the associated human health risks among native Africans. The human health risks of chrysotile include asbestosis, cancers, and mesothelioma, while toxic metal and rare earth elements induce oxidative stress which damages biomolecules such as deoxyribonucleic acid. Human health risks may also occur via synergistic interactions among toxic geogenic contaminants (e.g., chrysotile and toxic metals), and even between toxic geogenic contaminants and other health stressors such as the prevalence of infectious diseases. Mitigation measures to safeguard human health, and future research directions were highlighted.
Acknowledgements
This chapter is based on research project entitled, “The Potential of Native Plants of the Ultramafic Great Dyke of Zimbabwe for the Phytoremediation and Restoration of Metalliferrous Mine Wastes”, which was funded by the British Ecological Society (BES) Ecologists in Africa Grant No. 5774-6818. I am very grateful for the financial support provided by the British Ecological Society (BES) Ecologists in Africa. However, I am solely responsible for the views expressed in this chapter, and the decision to publish the research, BES, and its affiliates played no role whatsoever in the research and decision to publish the chapter.
References
1. Oze, C., Skinner, C., Schroth, A.W., Coleman, R.G., Growing up green on serpentine soils: biogeochemistry of serpentine vegetation in the Central Coast Range of California. Appl. Geochem., 23, 12, 3391–3403, 2008.
2. Alexander, E.B., Coleman, R.G., Harrison, S.P., Keeler-Wolfe, T., Serpentine geoecology of western North America: geology, soils, and vegetation, Oxford University Press, Oxford, 2007.
3. Bundschuh, J., Maity, J.P., Mushtaq, S., Vithanage, M., Seneweera, S., Schneider, J., Bhattacharya, P., Khan, N.I., Hamawand, I., Guilherme, L.R., Reardon-Smith, K., Medical geology in the framework of the sustainable development goals. Sci. Total Environ., 581, 87–104, 2017.
4. Gwenzi, W., Occurrence, behaviour, and human exposure pathways and health risks of toxic geogenic contaminants in serpentinitic ultramafic geological environments (SUGEs): A medical geology perspective. Sci. Total Environ., 700, 134622, https://doi.org/10.1016/j.scitotenv.2019.134622, 2020.
5. Davies, B.E., Bowman, C., Davies, T.C., Selinus, O., Medical geology: Perspectives and prospects, in: Essentials of medical geology, pp. 1–13, Springer, Dordrecht, 2013.
6. Goovaerts, P., Geostatistics: a common link between medical geography, mathematical geology, and medical geology. J. South. Afr. Inst. Min. Metall., 114, 8, 605–613, 2014.
7. Doocy, S., Daniels, A., Packer, C., Dick, A., Kirsch, T.D., The human impact of earthquakes: a historical review of events 1980-2009 and systematic literature review. PLoS Curr., 5, 2013, https://currents.plos.org/disasters/index.html%3Fp=6639.html.
8. Kut, K.M.K., Sarswat, A., Srivastava, A., Pittman Jr., C.U., Mohan, D., A review of fluoride in African groundwater and local remediation methods. Groundwater Sustainable Dev., 2, 190–212, 2016.
9. Oze, C., Fendorf, S., Bird, K.D., Coleman, G.R., Chromium geochemistry in serpentinized ultramafic rocks and serpentine soils from the Franciscan complex of California. Am. J. Sci., 304, 67–101, 2004.
10. Gwenzi, W., Mangori, L., Danha, C., Chaukura, N., Dunjana, N., Sanganyado, E., Sources, behaviour, and environmental and human health risks of high-technology rare earth elements as emerging contaminants. Sci. Total Environ., 636, 299–313, 2018.
11. Sleep, N.H., Meibom, A., Fridriksson, T., Coleman, R.G., Bird, D.K., H2-rich fluids from serpentinization: geochemical and biotic implications. Proc. Natl. Acad. Sci., 101, 35, 12818–12823, 2004.
12. Rajapaksha, A.U., Vithanage, M., Oze, C., Bandara, W.M.A.T., Weerasooriya, R., Nickel and manganese release in serpentine soil from the Ussangoda Ultramafic Complex, Sri Lanka. Geoderma, 189, 1–9, 2012.
13. Manning, A.H., Mills, C.T., Morrison, J.M., Ball, L.B., Insights into controls on hexavalent chromium in groundwater provided by environmental tracers, Sacramento Valley, California, USA. Appl. Geochem., 62, 186–199, 2015.
14. Blades, M.L., Foden, J., Collins, A.S., Alemu, T., Woldetinsae, G., The origin of the ultramafic rocks of the Tulu Dimtu Belt, western Ethiopia–do they represent remnants of the Mozambique Ocean? Geol. Mag., 156, 62–82, 1–21, 2017.
15. Antoniadis, V., Golia, E.E., Liu, Y.T., Wang, S.L., Shaheen, S.M., Rinklebe, J., Soil and maize contamination by trace elements and associated health risk assessment in the industrial area of Volos, Greece. Environ. Int., 124, 79–88, 2019.
16. Oberthür, T., Davis, D.W., Blenkinsop, T.G., Höhndorf, A., Precise U-Pb mineral ages, Rb-Sr and Sm-Nd systematics for the Great Dyke, Zimbabwe - constraints on crustal evolution and metallogenesis of the Zimbabwe Craton. Precambrian Res., 113, 293–306, 2002.
17. Stribrny, B., Wellmer, F.-W., Burgath, K.-P., Oberthür, T., Tarkian, M., Pfeiffer, T., Unconventional PGE occurrences and PGE mineralization in the Great Dyke: metallogenic and economic aspects. Miner. Deposita, 35, 260–281, 2000.
18. Morrison, J.M., Goldhaber, M.B., Mills, C.T., Breit, G.N., Hooper, R.L., Holloway, J.A.M., Diehl, S.F., Ranville, J.F., Weathering and transport of chromium and nickel from serpentinite in the coast range ophiolite to the Sacramento Valley, California, USA. Appl. Geochem., 61, 72–86, 2015.
19. Alexander, E.B. and DuShey, J., Topographic and soil differences from peridotite to serpentinite. Geomorphology, 135, 271–276, 2011.
20. Oury, T.D., Sporn, T.A., Roggli, V.L. (Eds.), Pathology of asbestos-associated diseases,