Trends in Urinary and Blood Cadmium Levels in U.S. Adults with or without Comorbidities, 1999–2018

Abstract

Although cadmium (Cd) exposure has been declining in the United States (U.S.) over the years, the level of exposure for people with pre-existing comorbidities is unclear. This study characterized the trends of blood Cd levels (bCd) (n = 44,498) and urinary Cd levels (uCd) (n = 15,107) by pre-existing comorbidities among adults participating in the U.S. National Health and Nutrition Examination Survey. We calculated age- and sex-standardized annual geometric mean (GM) levels, and used aJoinpoint regression model to examine the trends over time. The GM levels of bCd declined from 1999–2000 to 2017–2018 survey cycles (from 0.49 to 0.33 μg/L), while women and current smokers had higher levels. Participants with comorbidities had higher bCd and declined over time: cardiovascular disease (CVD) (0.50 to 0.42 μg/L), hypertension (0.49 to 0.35 μg/L), chronic kidney disease (CKD) (0.54 to 0.37 μg), and cancer (0.57 to 0.38 μg) versus those without these comorbidities. We observed the similar pattern of changes for uCd and participants with CVD, CKD, and cancer had higher levels. To conclude, the trend in urinary and blood Cd levels in U.S adults decreased in the past 20 years, and the levels varied by sex, smoking status, and comorbidities.

Relationship between blood cadmium levels and bone mineral density in adults: a cross-sectional study

“…The primary measures of cadmium exposure include blood and urinary cadmium, with urinary cadmium primarily reflecting cadmium body burdens, whereas blood cadmium changes more rapidly during cadmium exposure ( 7 ). Although urinary cadmium is considered to be a good biomarker of long-term renal accumulation, it may be influenced by several factors related to renal cadmium accumulation, such as the proportion of cadmium transferred to the kidney, the subsequent half-life in the kidney, or methods used to compensate for changes in urinary dilution, such as creatinine excretion or urine density, all of which influence changes in urinary cadmium concentrations ( 15 ).…”

“…The effects of diet and smoking on cadmium levels are significant, food leafy and root vegetables, cereals and offal are important sources of cadmium, long-term consumption of cereals and root vegetables will increase the accumulation of cadmium in the body ( 6 ). In addition, smoking is an important route of cadmium intake, the lungs have a higher cadmium absorption rate than the digestive tract, and cadmium levels in smokers are significantly higher than in non-smokers ( 7 ), and blood cadmium levels in non-smokers are less than 1 μg/L in most countries, whereas heavy smokers may have blood cadmium levels up to 7-fold higher. There are also differences in blood cadmium levels between different countries, with the average blood cadmium level of adults in the United States being lower than the average blood cadmium level of adults in Italy, Germany, Canada, and Australia ( 7 ).…”

“…In addition, smoking is an important route of cadmium intake, the lungs have a higher cadmium absorption rate than the digestive tract, and cadmium levels in smokers are significantly higher than in non-smokers ( 7 ), and blood cadmium levels in non-smokers are less than 1 μg/L in most countries, whereas heavy smokers may have blood cadmium levels up to 7-fold higher. There are also differences in blood cadmium levels between different countries, with the average blood cadmium level of adults in the United States being lower than the average blood cadmium level of adults in Italy, Germany, Canada, and Australia ( 7 ). Numerous prior investigations have shown an association between exposure to environmental cadmium and a number of illnesses, including osteoporosis, diabetes ( 8 , 9 ), kidney damage ( 10 ), and improper child growth and development ( 11 ).…”

Exposure to cadmium and lead is associated with diabetic kidney disease in diabetic patients

“…Although from 1999 to 2016, Americans experienced a dramatic decrease in Pb and Cd levels in their bodies, the ideal heavy metal content in the human body is 0 [22,23]. In available studies based on NHANES, the relationship of urinary and/or blood Pb and/or Cd with diabetes among the general population has been well established [24,25].…”

Association of Urinary Lead and Cadmium Levels, and Serum Lipids with Subclinical Arteriosclerosis: Evidence from Taiwan

“…In our previous study of a young Taiwanese population, we showed that higher levels of urine lead and cadmium levels were correlated with a greater carotid intima-media thickness (CIMT), a biomarker of subclinical arteriosclerosis [ 6 ], and endothelium–platelet microparticles, which are associated with endothelial damage [ 7 ]. Being alert to such danger, human exposure to lead and cadmium has been decreasing for decades [ 8 , 9 ]. However, exposure to low doses of lead and cadmium are still associated with adverse health outcomes in recent epidemiological studies [ 10 , 11 ].…”