A recent systematic review investigated the potential association between exposure to heavy metal pollution and cardiovascular disease risk.
In recent years, environmental heavy metal pollution has become a global public health concern. In part, this is because studies have shown that exposure to certain environmental heavy metals can increase the risk of cancer and negatively affect the immune system. However, the effect of heavy metals on cardiovascular health remains less well characterized.
Study helps researchers gain insight into how heart disease develops and progresses
Researchers believe that by investigating the potential association between heavy metal exposure and cardiovascular disease, they might be able to gain new insight into how cardiovascular disease develops and progresses. Furthermore, this information could potentially help guide future healthcare policies to reduce toxic metal pollution and cardiovascular disease risk.
A recent systematic review and meta-analysis by Chowdhury and colleagues, published in BMJ, investigated the association between five metal pollutants and cardiovascular disease. Specifically, the authors chose to focus on arsenic, lead, cadmium, and mercury because they are part of the World Health Organization’s list of “Ten chemicals of major public health concern”.
Additionally, the authors decided to include copper since it has been shown to promote plaque build-up in blood vessels and therefore might increase the risk of cardiovascular disease. The reviewers searched the PubMed, Embase, and Web of Science databases to identify 37 relevant studies, comprising of 348,259 non-overlapping participants.
Arsenic, lead, cadmium, copper were significantly associated with increased risk of heart diseases
In summary, the systematic review found that arsenic, lead, cadmium, and copper were significantly associated with an increased risk of coronary heart disease and cardiovascular disease, whereas mercury was not. In addition, lead and cadmium were associated with an increased risk of stroke, but not with arsenic.
These findings are mostly consistent with other studies and further emphasize the potential consequences of environmental toxin exposure on human health. For example, studies have shown that arsenic and lead can increase the risk of cardiovascular disease by increasing plaque build-up, contributing to high blood pressure, and causing inflammation. Similarly, previous research has shown that cadmium and copper can induce cardiovascular damage by promoting inflammation and oxidative stress. The only finding that the authors could not provide a complete biological explanation for was the lack of an association between mercury exposure and cardiovascular disease.
In conclusion, the current review demonstrates that exposure to certain metals, namely arsenic, lead, cadmium, and copper is associated with an increased risk of cardiovascular disease, whereas mercury is not. These findings, along with future studies, can be used to help educate the public regarding the negative effects of heavy metal pollution and to guide future healthcare policy.
Written by Haisam Shah, BSc
Reference: Chowdhury, R., Ramond, A., O’Keeffe, L. M., Shahzad, S., Kunutsor, S. K., Muka, T., … & Chowdhury, S. (2018). Environmental toxic metal contaminants and risk of cardiovascular disease: systematic review and meta-analysis. BMJ, 362, k3310.