Alterations in antioxidant defense system of workers chronically exposed to arsenic, cadmium and mercury from coal flying ash

Abstract

Humans are exposed to different stress factors that are responsible for over-production of reactive oxygen species. Exposure to heavy metals is one of these factors. The aim of the study was to analyze the effect of chronic exposure to heavy metals through coal flying ash on the efficiency of antioxidative defensive mechanisms, represented by the activity of superoxide dismutase, glutathione peroxidase and ascorbic acid. Nonessential elements such as arsenic and mercury levels showed a significant increase (p > 0.001) in the power plant workers rather than in the control subjects. There were no significant differences of blood cadmium between power plant workers and control subjects. We found a significant positive correlation (p < 0.05) between BAs/SZn (r = 0.211), BAs/BSe (r = 0.287), BCd/SCu (r = 0.32) and BHg/BSe (r = 0.263) in the plant workers. Red blood cell antioxidant enzymes and plasma ascorbic acid were significantly lower in power plants workers than in the control group (p < 0.002). We can conclude that levels of mercury, arsenic and cadmium in blood, despite their concentration within the reference values, significantly affect plasma ascorbic acid concentration, superoxide dismutase and glutathione peroxidase activity, which are able to increase the risk of oxidative stress.

Recruitment strategies and challenges: Lessons learned from a coal ash and children's health study

“…Most researchers have conducted studies in workers exposed to fly ash. Occupational researchers report relationships between exposure to fly ash and increased arsenic and mercury levels in exposed workers (Zeneli, Sekovanic, Ajvazi, Kurti, & Daci, ), increased oxidative stress (Zeneli et al, ), increased frequencies of chromosomal aberrations (Bauman, & Horvat, ; Leonard, Deknudt, Leonard, & Decat, ), respiratory effects (Cho, Cho, Shrivastava, & Kapre, ), and earlier mortality from cancer (Bencko, Rames, Fabianova, Pesek & Jakubis, ).…”

Memory and fine motor skill test performance among children living near coal ash storage sites.

“…Occupational studies have found that power plant workers who were exposed to fly ash had significantly higher blood levels of arsenic and mercury compared to healthy controls (Zeneli, Sekovanic, Ajvazi, Kurti, & Daci, 2016).…”

Coal ash exposure and asthma in children.

“…It has been demonstrated that coal fly ash is a very real exposure for those who work in jobs where coal combustion occurs (21). A study published in 2015 by Zeneli et al.…”

“…A study published in 2015 by Zeneli et al. examined the relationship between fly ash and how it affected the antioxidant defense systems of power plant works in Kosovo (21). A total of 97 adult male participants were selected, 70 were power plant workers and 27 were healthy inhabitants of the Dragash rural municipality, a location considered to be relatively free of air pollution.…”