Exposure to toxic metals is associated with increased risk of subclinical atherosclerosis, states a new study.

The study reported in the journal Arteriosclerosis, Thrombosis and Vascular Biology was conducted among 1873 persons, aged 40-55 years from the Aragon Workers Health study between 2011 and 2014. The selected participants were employed at an auto assembly factory in Spain. Around 97% of them were men. Unlike earlier published studies, which had mainly examined the association of exposure to metals and subclinical atherosclerosis in carotid arteries, the present study widened its scope to also include the femoral and coronary arteries. The impact of exposure to nine toxic metals (arsenic, barium, uranium, cadmium, chromium, antimony, titanium, vanadium and tungsten) on atherosclerosis was examined. Urinary levels of these metals were measured. Ultrasound of the carotid and femoral arteries plus coronary calcium scoring tests were done to assess atherosclerosis.

Results showed high urinary levels of most of the metals studied among older adults and the few female study participants. Compared to never smokers, the smokers had higher levels of cadmium, chromium, titanium and arsenic. The chances of subclinical atherosclerosis were higher in the presence of high levels of arsenic, cadmium, titanium, and potentially antimony. The adjusted odds ratio for subclinical atherosclerosis presence in at least one territory was 1.26 for titanium, 1.67 for cadmium and 1.25 for arsenic.  The combination of arsenic, cadmium and titanium was more toxic to the arteries. Examination of individual vascular sites revealed an association of titanium and possibly cadmium and antimony with increased plaques in coronary arteries. Cadmium and arsenic were associated with increased plaques in the carotid arteries, while cadmium and titanium increased risk of plaque formations in the femoral arteries.

Heavy metals contribute significantly to environmental pollution through industrial emissions. Hence, there is always some exposure to metals because of air pollutants and also via contaminated soil, drinking water or tobacco smoke in those who smoke, which is toxic for heart health. This study has implicated heavy metals such as arsenic and cadmium in atherosclerosis and has also identified titanium and antimony as potential atherosclerosis risk factors. Arsenic and cadmium are often found in tobacco and food, while arsenic is also found in water. Dental and orthopedic implants, screws, pacemaker encasings, cosmetic products and some foods are main sources of titanium exposure. The authors conclude that “Exposure reduction and mitigation interventions of these metals may decrease cardiovascular risk in individuals without clinical disease”.

Reference

1. Grau-Perez M, et al. Toxic metals and subclinical atherosclerosis in carotid, femoral, and coronary vascular territories: The Aragon Workers Health Study. Arterioscler Thromb Vasc Biol. 2021 Dec 9;ATVBAHA121316358. doi: 10.1161/ATVBAHA.121.316358.