By Chloe Wornell –
Electronics play a huge role in all aspects of daily life, from entertainment purposes to food preparation. However, the production of these devices can lead to severe health issues for people who rely on the land around these sites due to the contamination of the soil from heavy metals that are produced as waste by these factories.
Figure 1 “Soil chemical contamination” by JungleNews is licensed under CC BY 4.0 via Wikimedia Commons
Heavy metals are defined as ‘naturally occurring elements that have a high atomic weight and a density of a least 5 times greater than that of water.’ [1]. They have multiple uses across various industries which have led to the contamination of soils and water and subsequent exposure to them worldwide but more widely in developing countries. Studies have found that frequent exposure to heavy metals can have severe health complications, [2] on humans and people who rely on these contaminated areas for food suffer greatly. This also has global impacts as many of the affected areas are agricultural land that exports their produce around the world – despite several measures trying to limit the exposure to heavy metals globally, the amount of heavy metal exposure is continuing to grow on a global scale [3].
Xiangyang, a large city in the Hubei province within China, has built several electronics manufacturing factories and over the last few decades has released many heavy metals into the surrounding area for the last 20 years. The surrounding area of the factory consisted mainly of farmland with approximately 400 people living there. The study consisted of 136 samples of topsoil being taken throughout the surrounding area and then using different chemical analysis techniques to find the concentrations of seven heavy metals (Lead, Nickel, Cadmium, Arsenic, Zinc, Copper and Chromium). The pollution levels were then measured using the Geoaccumulation Index (Igeo), Pollution Index (PI) and the Potential Ecological Risk Index (PER) as well as completing a human health risk assessment to assess the environmental and social impact that the contamination is causing. The analysis of the pollution in the chosen samples indicated that there were large amounts of Chromium and Cadmium which is linked to extremely polluted conditions. The study, during its assessment on the risk to human health, found that whilst there are multiple ways for heavy metals to enter the body – ingestion contributed the most to the daily intake of heavy metals – the daily average intake for children in the area was approximately 6.83×102 mg kg-1 [4]. Exposure has short-term and long-term effects, and long-term exposure especially from a young age can lead to ‘neurocognitive disorders, behavioural disorders, respiratory problems, cancer and cardiovascular diseases.’ [5]. Figure 1 depicts the potential for soil contamination surrounding these factories.
This study, among others, indicates the importance of the health of our soil as contaminated soils lead to contaminated food; contaminated food will cause significant decreases in many people’s quality of life due to the severe and life-threatening health complications that frequent exposure can cause. So, I’ll ask again, which do you prefer?
References and further reading
[1] Tchounwou, P., Yedjou, C., Patlolla, A. and Sutton, D., 2012. Heavy Metal Toxicity and the Environment. Experientia Supplementum, pp.133-164.
[2] Olawoyin, R., Oyewole, S. and Grayson, R., 2012. Potential risk effect from elevated levels of soil heavy metals on human health in the Niger delta. Ecotoxicology and Environmental Safety, 85, pp.120-130.
[3] Jaishankar, M., Tseten, T., Anbalagan, N., Mathew, B. and Beeregowda, K., 2014. Toxicity, mechanism and health effects of some heavy metals. Interdisciplinary Toxicology, 7(2), pp.60-72.
[4] Wu, W., Wu, P., Yang, F., Sun, D., Zhang, D. and Zhou, Y., 2018. Assessment of heavy metal pollution and human health risks in urban soils around an electronics manufacturing facility. Science of The Total Environment, 630, pp.53-61.
[5] Al Osman, M., Yang, F. and Massey, I., 2019. Exposure routes and health effects of heavy metals on children. BioMetals, 32(4), pp.563-573.
