Higher metal levels were linked to more deaths over a nearly 20-year research period.
Higher levels of six metals—cadmium, tungsten, uranium, cobalt, copper, and zinc—are directly linked to increased cardiovascular disease and mortality.
Researchers at Columbia University found that study subjects who had a mixture of these six metals in their urine had an increased mortality risk of 66 percent. During the 18-year study, they also discovered that participants experienced a 29 percent increase in cardiovascular disease.
Copper and Cadmium Increased Risks Most
The study subjects, whose average age was 62, were recruited from Chicago, New York City, the Baltimore area, the Los Angeles area, St. Paul, and the Winston-Salem area of North Carolina. They joined the study group in 2000–2001 without cardiovascular disease and were followed until 2019.
- Copper: 42 percent
- Uranium: 32 percent
- Cadmium: 25 percent
- Cobalt: 24 percent
- Zinc: 21 percent
- Tungsten: 20 percent
For all-cause mortality, people with high urinary cadmium had increased risk as follows:
- Cadmium: 68 percent
- Copper: 50 percent
- Zinc: 38 percent
- Cobalt: 37 percent
- Uranium: 32 percent
- Tungsten: 16 percent
“The 10-year survival probability curves for the individual metals and all-cause mortality showed a consistent decrease of survival probabilities per increases in the baseline urinary levels of cadmium, cobalt, copper, and zinc,” the authors wrote.
6 New Metals Studied
The researchers noted that past studies assessing the toxicity of metals were mainly limited to three metals: arsenic, cadmium, and lead.
Cadmium, tungsten, and uranium are nonessential metals that may be toxic, while cobalt, copper, and zinc are essential metals that perform important tasks in the body but are harmful in excess.
These six metals were selected because of their association with coronary artery calcification, a sign of atherosclerosis, which is fatty degeneration of the arterial lining, the researchers said.
High levels of these metals in the urine can indicate excess exposure.
Influencing Policy
Although metals such as uranium and tungsten have been studied less than arsenic, lead, and cadmium for toxicity, Martinez-Morata said they are common in the United States. The six metals investigated in this study can be ingested via water, food, air pollution, and indoor dust.
This study was undertaken to influence federal policies and regulations regarding air pollution, drinking water, food contamination, and consumer products, Martinez-Morata said in the press release.
“Federal regulations for lowering maximum contaminant levels for drinking water and banning leaded gasoline, for example, have successfully reduced exposure to toxic metals such as arsenic, cadmium, and lead in water and air, much more study is needed to understand the contributions of such metals as tungsten and cobalt,” she said.
Column: Finally, a limit to Donald Trump’s Teflon superpower — J.D. Vance