Cardiovascular Toxicity in Copper Production Workers Exposed to Heavy Metals

Abstract

Introduction. Cardiovascular diseases (CVD) are a leading cause of morbidity and mortality. The role of occupational hazards in the CVD prevalence remains to be clarified. Material and methods. Here we report the results of the study of risk factors and CVD prevalence in 590 workers at the largest copper production plants in the Sverdlovsk region, exposed to heavy metals in the workplace. The workers` health information was obtained during a regular medical examination in 2018. The lead concentration increase to 1.3-1.8 occupational exposure limits was registered in the working areas of the concentrating mill (for bunkerman) and copper smelting workshops (transporter, smelter, converter, non-ferrous metal spreader, repairman, electrician). Results. We studied the exposure indices (Pb level in blood), the response markers (reticulocyte count, erythrocytes basophilic stippling, coproporphyrin, and aminolevulinic acid in the urine), and their correlation to a working tenure. Based on this analysis, we attributed CVD risk factors and cardiovascular diseases to the occupation, in order to potentially modify some of those risk factors and ultimately inform the risk management. Hypertension occurred in 57% of the examined workers, which is higher than in the general population. We calculated relative risk, confidence intervals and attributable fraction. We developed a predictive mathematical model (stepwise logistic regression) to predict high-stage hypertension and identified the risk factors associated with its development. Conclusions. Correlation analysis revealed direct correlations between stages 2 and 3 hypertension and a working tenure over 20 years. We think it’s reasonable to consider the documented CVDs as related to the toxic effects of heavy metals (lead and cadmium).

Exploring the Link Between the Serum/Blood Levels of Heavy Metals (Pb, As, Cd, and Cu) and 2 Novel Biomarkers of Cardiovascular Stress (Growth Differentiation Factor 15 and Soluble Suppression of Tumorigenicity 2) in Copper Smelter Workers

“…The study suggested that the observed CVDs were attributed to the toxic effects of heavy metals especially Pb and Cd. 75 Concerning the medical history and examination in the current work, almost all cardiovascular and general manifestations (apart from edema of lower limbs and dizziness) showed a statistically significant elevated prevalence (P < 0.05) among the exposed Cu smelter workers when compared with the controls (Table 2). Approximately 34% of the exposed workers (n = 14) gave a history of exertional dyspnea, whereas 44% (n = 18) of the workers experienced chronic cough and 34% had recurrent expectoration.…”

“…Twenty-four–hour ECG Holter monitoring revealed an elevated mean heart rate and more frequent premature supraventricular and ventricular contractions among Cu smelter workers compared with the healthy control subjects 76 . In another study on the prevalence and risk factors of CVDs, hypertension was detected among 57% of the examined 590 workers who were employed at the largest Cu production plants in the Sverdlovsk region 75 …”

“…76 In another study on the prevalence and risk factors of CVDs, hypertension was detected among 57% of the examined 590 workers who were employed at the largest Cu production plants in the Sverdlovsk region. 75 The associations between age, smoking status, and BMI with GDF-15 levels were assessed among Cu smelter workers. The study showed the absence of any correlation among these parameters.…”

“…Another more recent study demonstrated a significant prevalence of CVDs among more than 500 workers who were exposed to heavy metals at a Cu production plant in the Sverdlovsk region. The study suggested that the observed CVDs were attributed to the toxic effects of heavy metals especially Pb and Cd 75 …”

Copper Deficiency Induces Oxidative Stress in Liver of Mice by Blocking the Nrf2 Pathway

“…When there is a systemic Cu de ciency, it can cause Cu metabolism disorders [5]. But Cu must be a trace amount in the body, and when the amount exceeds the needs of cells, it can also cause toxic damage to the liver and other organs [6,7]. The former represents Menkes disease, the latter is Wilson disease.…”