Cadmium exposure and cigarette papers

Today's article is about cadmium and cadmium compounds in cigarette smoke. Only one of many reasons first-hand and second-hand smoke is so dangerous.

Cadmium is  a heavy metal and can cause all kinds of health problems. Here are some studies linking cadmium exposure from cigarette papers. The papers are soaked in cadmium compounds to make it smolder slowly instead of burn.

- Cigarette Smoke Cadmium Breakthrough from Traditional Filters: Implications for Exposure. 2015.

1. Cadmium, an IARC group 1 human carcinogen, is highly toxic to renal, skeletal, nervous, respiratory, and cardiovascular systems. Pulmonary exposure to nebulized cadmium compounds induces emphysema and pulmonary interstitial fibrosis. Elevated blood cadmium levels are strongly associated with increased prevalence of peripheral artery disease. Pancreatic cancer has been associated with smoking and elevated urine cadmium concentrations. Elevated cadmium/zinc ratios in serum of smokers has been suggested as a critical determinant for risk of prostate cancer.
2. Cadmium passed through 44 mm filters typically used on linear smoking machines to an even greater degree, ranging from 13.6% to 30.4%.
3. Cadmium has a biological half-life of 13.6 to 23.5 years. That means in 23.5 years only HALF will be gone from the body.
4. Concentrations of toxic metals such as barium and manganese are much higher than cadmium concentrations in tobacco.16,17 Cadmium, however, has a lower propensity to form nonvolatile oxides relative to many metals such as these. Therefore, cadmium, like its periodic homologue mercury, is a relatively volatile metal that is readily transported in tobacco smoke.
5. In this study platinum traps were used to trap cadmium in order to more accurately find out how much cadmium comes out of cigarette smoke. 

- Lead, Cadmium, Smoking, and Increased Risk of Peripheral Arterial Disease. 2004.
Blood lead and cadmium, at levels well below current safety standards, were associated with an increased prevalence of peripheral arterial disease in the general US population.

- The German Environmental Survey 1990/1992 (GerES II): cadmium in blood, urine and hair of adults and children. Published 2000.
Active cigarette smoking was found to be dominant in affecting blood and urine cadmium levels in adults, but less important for cadmium levels in hair.

- Establishment of Toxic Metal Reference Range in Tobacco from US Cigarettes. Journal of Analytical Toxicology. 2013.

1. Among the more than 4,000 identified compounds in smoke, many metals contribute to the health risks associated with tobacco use.
2. Specific metals found in tobacco and tobacco smoke have been classified as carcinogens by the IARC.
3. The methods were utilized to examine arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, mercury, and nickel content in cigarette tobacco and to establish a reference range for the metals in 50 varieties of cigarettes available in the U.S.
4. At the time of the study about 20% of US citizens were still smokers. 
5. In addition to being a carcinogen, cadmium is associated with development of chronic obstructive pulmonary disease (COPD) and toxicity to kidneys.
6. Though barium and manganese concentrations in tobacco are readily measurable, neither is as efficiently transported into smoke as more volatile elements, such as cadmium and lead.
7. Detection limits of the instruments used were down to the fraction of a microgram. 
8. For mean concentrations of various dangerous metals, see Table 3.

Each of these studies references many more studies showing the toxicity of cigarette smoke and heavy metals therein. See the actual studies for more information.

More sources and studies

1. IARC monograph on cadmium. PDF. Monographs summarize data that we know, list studies as the sources, and are updated periodically when new information is available.
2. Toxicological profile of cadmium. 2012 PDF.
3. Navas-Acien A, Selvin E, Sharrett AR, Calderon-Aranda E, Silbergeld E, Guallar E. Lead, cadmium, smoking, and increased risk of peripheral arterial disease. Circulation. 2004;109:3196–201. Pubmed.