An Investigation of Organic and Inorganic Mercury Exposure and Blood Pressure in a Small-Scale Gold Mining Community in Ghana

Abstract

There is increasing concern about the cardiovascular effects of mercury (Hg) exposure, and that organic methylmercury and inorganic Hg2+ may affect the cardiovascular system and blood pressure differentially. In small-scale gold mining communities where inorganic, elemental Hg exposures are high, little is known about the effects of Hg on blood pressure. In 2011, we assessed the relationship between Hg exposure and blood pressure (BP) in a cross-sectional study of adults from a small-scale gold mining community, Kejetia, and subsistence farming community, Gorogo, in Ghana’s Upper East Region. Participants’ resting heart rate and BP were measured, and hair and urine samples were provided to serve as biomarkers of organic and inorganic Hg exposure, respectively. Participants included 70 miners and 26 non-miners from Kejetia and 75 non-miners from Gorogo. Total specific gravity-adjusted urinary and hair Hg was higher among Kejetia miners than Kejetia non-miners and Gorogo participants (median urinary Hg: 5.17, 1.18, and 0.154 µg/L, respectively; hair Hg: 0.945, 0.419, and 0.181 µg/g, respectively). Hypertension was prevalent in 17.7% of Kejetia and 21.3% of Gorogo participants. Urinary and hair Hg were not significantly associated with systolic or diastolic BP for Kejetia or Gorogo participants while adjusting for sex, age, and smoking status. Although our results follow trends seen in other studies, the associations were not of statistical significance. Given the unique study population and high exposures to inorganic Hg, the work contained here will help increase our understanding of the cardiovascular effects of Hg.

Multiple elemental exposures amongst workers at the Agbogbloshie electronic waste (e-waste) site in Ghana

“…Urinary elements analyzed included toxic chemicals (arsenic, As; cobalt, Co; chromium, Cr; Hg; nickel, Ni; Pb) and essential elements (Cu, Zn). Total Hg levels in blood and urine were quantified using a Direct Mercury Analyzer 80 as previously outlined (Basu et al, 2014; Rajaee et al, 2015). For all other elements, the urine and blood samples were digested with nitric acid as outlined elsewhere (Basu et al, 2011), and elemental concentrations determined using Inductively Coupled Plasma Mass Spectrometer (ICPMS; Varian 820MS).…”

The aging kidney and the nephrotoxic effects of mercury

“…Similarly, Kostial et al (1978) compared the distribution of Hg 2+ in 2-week-old to 21-week-old rats and found that renal accumulation of Hg 2+ was higher in kidneys of older rats (Kostial et al 1978). Interestingly, chronic exposure to MeHg was found to correlate with development of Type II diabetes (Schumacher and Abbott 2016) and hypertension (Houston 2011; Rajaee et al 2015), which are considered to be significant risk factors of CKD (Ginsberg et al, 2014). Therefore, exposure to Hg may contribute to the development of CKD or it may enhance the progression of the disease.…”

An Agent Based Model to Analyze the Bitcoin Mining Activity and a Comparison with the Gold Mining Industry

“…In addition, the gold industry has caused environmental and health problems for decades to miners and mining communities. For example, there is an increasing concern for the health of miners and mining communities related to the mercury exposure, a toxic metal used in small-scale gold mining, and for the ecosystems' degradation due to mining land use [8,9]. Therefore, looking at the total mining costs, such as production costs, economic costs, environmental costs, and social costs, of these two assets or "safe havens", probably a wide spread of Bitcoin could allow us to better address the environmental aspects of sustainability and to have substantially higher savings than gold [8][9][10][11][12].…”