Claude Monet, Bordighera (1884), oil on canvas, 65 x 80.8 cm, The Art Institute of Chicago. Yellows used here are based on cadmium pigments. There were periods during Monet's long career that became dominated by motifs of trees. In Bordighera, he captures the forms of trees poised above the town, with their richly-coloured bark and intense coloured foliage. Monet passed away of lung cancer on 5 December 1926 at the age of 86.
Health Effects of Cadmium (Cd) Exposure
- Renal toxicity -> decreased GFR
- Increased risk of Osteoporosis in menopausal women -> Ammonium increases bone reabsorption
- Estrogen-like effect (acts as estrogen)
According to the Agency for Toxic Substances and Disease Registry, foods account for more than 90 percent of human exposure to cadmium. On average, people consume about 30 micrograms of cadmium daily through a normal diet, absorbing 1 to 3 micrograms. There is currently no evidence that these trace levels pose a hazard to healthy, non-smoking adults, however, studies have shown that smokers can absorb twice that amount per day.
Source: The Facts on Cadmium, http://www.dartmouth.edu/~toxmetal/toxic-metals/more-metals/cadmium-faq.html
Cadmium Pigments In Artists' Paints
Cadmium sulfide (CdS) was suggested as a pigment in 1819 by Stromeyer. It became commercially available 1840s due to scarcity of metal required for its production. Cadmium sulfide selenides(CdSe) (cadmium sulfoselenides),was originally commercialized in 1910.
The following are commonly used cadmium pigments in artists' paints:
Light shades of cadmium yellow is cadmium zinc sulfide, typically a greenish yellow, solid solution of CdS and ZnS. Colour Index Pigment Yellow 35 (PY35).
Deep shades of cadmium yellow is cadmium sulfide (CdS).Colour Index Pigment Yellow 37 (PY37).
Cadmium orange is cadmium sulfoselenide, a solid solution of CdS and CdSe. Depending on the sulfur to selenide ratio, Colour Index Pigment Orange 20 (PO20) or Colour Index Pigment Red 108 (PR108) is obtained.
Cadmium red is cadmium sulfoselenide. Colour Index Pigment Red 108 (PR108).
Cadmium green is sometimes a mixture of cadmium yellow and viridian(blue-green pigment ) to give a bright, pale green mixture.
1. Cadmium Colors—It Began with Medicine, Natural Pigments Inc, https://www.naturalpigments.com/artist-materials/cadmium-colors/
2. The Episodic Table of Elements, A CHEMISTRY PODCAST ABOUT THE FASCINATING TRUE STORIES BEHIND EACH ELEMENT ON THE PERIODIC TABLE.
Distributed in the organism in muscles, liver and kidneys -> binds to proteins
Slowly excreted via the kidneys
Kidneys: 10-30 years
Blood: 3-4 months
Kidney damage measured:
Reduced GFR (shown on blood work)
Earliest signs of kidney damage = measure proteins, NAG and B2 and A1 microglobulin
Early still = beta 2 and alpha 1 microglobulin and retinol-binding protein as well as N-acetyl glucoamindase (NAG)
The damage is believed to be irreversible
Bioavailability: Heavy metal -> excreted exclusively in the urine = cannot be metabolised by the liver
Measured in the urine (heavy metal)
If seen in the blood = recently exposed
Women have higher levels than men
CFR - Code of Federal Regulations Title 21 - FDA: Regulations prescribing conditions under which food additive substances may ..V- Sec. 172.325 Bakers yeast protein. Less than 0.3 parts per million (ppm), Arsenic 0.1 ppm, Cadmium 0.4 ppm, Lead, 0.05 ppm Mercury, and 0.3 ppm Selenium
Sec. 172.898 Bakers yeast glycan. (b) The additive meets the following specifications on a dry weight basis: Less than 0.4 part per million (ppm) arsenic, 0.13 ppm cadmium, 0.2 ppm lead, 0.05 ppm mercury, 0.09 ppm selenium, and 10 ppm zinc.
1. The provisional tolerable weekly intake (PTWI) of Cd set by the Joint FAO/WHO Expert Committee on Food Additives,
or EFSA Panel on Contaminants in the Food Chain (CONTAM)
A person weighs 60 kg (132 lbs) and eats approx. 100 g dark chocolate per week.
Calculate what proportion of PTWI such an intake constitutes if the cadmium content corresponds to the limit value.
100 g of chocolate contains 0.08 mg = 80 .g of cadmium
A person weighing 60 kg may consume 150 µg cadmium / week
100 g of chocolate will thus correspond to 80 x 100/150 = 53% of PTWI
Exposure levels: Cd can have health effects at much lower exposure levels. Uptake, distribution and excretion: Recorded orally or pulmonarily (depending on particle size)
Itai-itai (IID), Cadmium and Rheumatoid Disease
There was an endemic disease of unknown etiology in the Jinzu River basin of Toyama, Japan. It was a painful condition called 'itai-itai' (itai, meaning ouch). Patients complained of bone pain, especially in the pelvic girdle and legs while walking. It was in 1946, just after the Second World War, when itai-itai disease began to be medically evaluated. The local agricultural association requested Kanazawa University to conduct an investigation, Nagasawa et al., () conducted this investigation and published their results the following year. In that paper, the authors referred to this endemic disorder as a rheumatoid disease.
The 35-year history of 'itai-itai' has been divided into three periods: (1) 1955−1961, an early phase of epidemiology, symptom characterization and attempts at treatment; (2) a middle period during which diagnostic criteria were formalized and research focused on the influence of heavy metal contamination, particularly Cd; and (3) around 1970−1990, a third period in which the role of Cd accumulation in disease etiology was firmly established.
Itai-itai disease (IID) is the most severe form of chronic cadmium (Cd) intoxication of human. The patients of IID suffer from renal anemia, tubular nephropathy and osteopenic osteomalacia, and 90% of the patients are post-menopausal women. Experiments suggest concurrent administration of estradiol helps the vitamin D therapy for IID patients and the removal of Fe at the mineralization front of bone (3) is important for the recovery to normal bone remodeling.
1. Keiko Aoshima, Itai-itai disease: Renal tubular osteomalacia induced by environmental exposure to cadmium—historical review and perspectives.
Soil Science and Plant Nutrition, 2016, Pages 319-326. https://www.tandfonline.com/doi/full/10.1080/00380768.2016.1159116
2. Takashi Umemura and Yumi Wako. Pathogenesis of osteomalacia in itai-itai disease. Journal of Toxicologic Pathology, 2006: 19: 69-74. https://www.jstage.jst.go.jp/article/tox/19/2/19_2_69/_pdf.