Cadmium

CADMIUM TOXICITY

As do Mercury and Lead, Cadmium gets into our cells, and like an unwelcome guest, Cadmium stays too long (the biological half-life of Cadmium, the time required for post-exposure cellular Cadmium content to fall by 50%, is 10 years). Cadmium binds irreversibly to sulfhydryl groups on the exposed active sites of intracellular enzymes, inactivating them, rendering them functionally useless, gumming up our biochemistry. As with Mercury and Lead, Cadmium has been linked to cardiovascular disease, hypertension, and kidney disease. Recently published research has shown Cadmium to be a cause of defective DNA repair and a source of pathological Estrogen stimulation, linking Cadmium to Breast and Prostate cancer, the prevalence of which is rising at an epidemic rate - When I was in med school, the teaching was that 1 in 30 women would develop breast cancer during their lifetime; now it’s 1 in 8. Have women changed or is it something in our environment that has changed? Prostate cancer used to be “an old man’s disease”; now we see it in 50 year olds (Testosterone is not the cause of Prostate cancer; if it were, we would all get Prostate cancer at age 18. We don’t, but we’re sure likely to get it at age 81, when our Testosterone levels are low. As we age, we make less and less Testosterone, but we convert more of it into Estrogen, which increases our risk for prostate cancer). Environmental Estrogenic agents, like Cadmium, thus amplify and increase cancer risk in both sexes.

Cadmium is a white metal used in batteries, metal coatings, plastics, alloys, and pigments. Cadmium is poorly biodegradable, so once dumped into the environment, it hangs around a long time. Cadmium is concentrated by the tobacco plant from the soil, and from there reaches the lungs, circulation, and body cells of smokers (each cigarette provides you with 0.1 mcg of Cadmium; smokers have intracellular Cadmium levels twice that of non-smokers). Free radical damage due to Cadmium is one of the causative links between smoking and cardiovascular disease, cancer, and lung disease. Lung disease continues to progress in smokers even after they have stopped smoking, because the Cadmium is still in there, causing free radical stress and inflammation (One small study demonstrated that intravenous EDTA, which binds tightly to Cadmium, improved lung function in smokers with active lung disease).

Our genetic blueprint is contained in the DNA of our cells. If the DNA is damaged during cellular replication, or by free radical stressors (such as Mercury, Lead, or Cadmium), then the cell becomes dysfunctional; it may degenerate into a cancer cell. DNA damage is not an infrequent event during normal life (i.e. sunburn), thus Mother Nature provides us with enzyme systems to carry out DNA repair. Cadmium inactivates this DNA repair mechanism. In a study of DNA replication and repair in yeast cells, Cadmium exposure increased the cellular mutation rate 2,000-fold. Cadmium exposure is thus a cancer double-whammy; Cadmium damages not just our DNA, but also our capacity to repair damaged DNA.

In an autopsy study carried out in North Carolina, tissue Cadmium content correlated with the risk of dying of cardiovascular disease (to protect yourself, leave North Carolina, or stay in North Carolina and take steps to protect yourself from Cadmium). Like Mercury, Cadmium is handed down from mother to child. The hair Cadmium level in mothers correlates directly with the hair Cadmium level of their newborn offspring, which correlated inversely with the birth weight of the infants. In other words, the greater your Cadmium burden, the smaller will be your babies. Cadmium is associated with hypertension (in one study, blood Cadmium levels averaged 3-4 ng/ml in non-hypertensives, and all had a level below 8, while the average level in hypertensives was 11 ng/ml, and 3/4ths of the hypertensives had levels above 8, so you shouldn’t be surprised by the finding that infants of hypertensive mothers have hair Cadmium levels three times that of infants of non-hypertensive mothers. You’ve heard that cigarette smoking is associated with low birth weight; now you know why – it’s the Cadmium.

In general, water “hardness”, which reflects its content of Magnesium and Calcium, correlates with a reduced risk of hypertension and cardiovascular disease, but that’s not the case in the twin Kansas Cities. Both draw their drinking water from the same source, but they process it differently. The water in KC, Kansas is twice as hard as is the water in KC, Missouri, and this increased water “hardness” should be protective, but the prevalence of hypertension is greater in KC, Kansas, and this correlates with a 10-fold greater level of Cadmium in the blood of KC, Kansas residents. It seems that in KC, Kansas “they’ve gone as far as they can go” to increase the workload of their cardiologists. If you live in KC, Kansas, you could move across the river, or you could stay in Kansas and take steps to protect yourself (and you’re children, those alive, and those still in the planning stage) from Cadmium overload and its health consequences.

Cadmium is bad stuff; we don’t want it but we can’t avoid it, so we need to take steps to protect ourselves. Testing for Cadmium is difficult. As Cadmium accumulates within our cells and stays there for 10 years, blood levels of Cadmium are of little value in assessing one’s body Cadmium burden and Cadmium associated health risk. Kidney and liver biopsy will provide an accurate measure, but this approach has obvious limitations. To best asses Cadmium burden, physicians trained in heavy metal detoxification will carry out a “mobilization - challenge”. The individual being tested will take oral Cadmium binding agents (such as EDTA and DMSA) for several days. A weight-based dose of intravenous EDTA is then administered, and the subject’s urine is collected over 6 hours and analyzed for Cadmium (and other toxic metal) content. Cadmium overload is treated with intravenous EDTA and high-dose oral DMSA, along with antioxidant and nutritional support.