Analysis for threshold levels of cadmium in urine that induce tubular dysfunction among women in non-polluted areas in Japan.
ABSTRACT To examine if there is a threshold in urinary cadmium concentration that induces elevation in urinary microglobulins.
The database developed in a previous field survey (Ezaki et al. 2002) was employed. In the survey conducted in 2000 and 2001, more than 10,000 middle-aged women (with no occupational exposure to Cd) in ten prefectures all over Japan gave morning spot urine samples, which were analyzed for cadmium (Cd-U), calcium (Ca-U), magnesium (Mg-U), zinc (Zn-U), alpha(1)- and beta(2)-microglobulins (alpha(1)- and beta(2)-MG-U), and creatinine (cr). The urinary analyte concentrations were corrected for cr concentration (to be expressed as, e.g., Cd-Ucr), and the data thus obtained were subjected to statistical evaluation. The largest geometric mean (GM) for Cd-Ucr among the ten prefecture was 3.2 microg Cd/g cr, and the maximum Cd-Ucr observed among the women studied was 20.9 microg Cd/g cr.
Both alpha(1)-MG-Ucr and beta(2)-MG-Ucr increased as a function of the increase in Cd-Ucr among all the women and also in sub-populations of narrow age ranges (i.e., 41-50 and 51-60 years), with no apparent threshold Cd-Ucr. Comparison of the cases exceeding cut-off alpha(1)-MG-Ucr and beta(2)-MG-Ucr levels also indicated a Cd dose-dependent increase in the prevalence, similarly without a threshold Cd-Ucr. In addition, such findings were essentially reproducible when elevation in alpha(1)-MG-Ucr and beta(2)-MG-Ucr levels was examined with the three essential elements, especially with Ca-Ucr and Mg-Ucr, although less clearly with Zn-Ucr. The observations as a whole suggest a possibility that the dose-dependent increases in alpha(1)-MG-Ucr and beta(2)-MG-Ucr with no apparent threshold for element concentration is not specific to Cd-Ucr but common to other elements.
No threshold Cd-Ucr was detected in relation to the increases in alpha(1)-MG-Ucr and beta(2)-MG-Ucr. The element dose-dependent increases in the two MGs with no threshold in the element concentration might be not limited to Cd, but common to other elements. Further studies are apparently necessary.
Article: Reverse Effect of Vitamin E on Oxidative Stress, Derivatives and Conductivity Changes of Hemoglobin Induced by Exposure to Cadmium[show abstract] [hide abstract]
ABSTRACT: Cadmium is a toxic heavy metal which causes oxidative damage in organisms. Vitamin E is effective antioxidant and free radical scavenger. Therefore, the present study concentrates on the potency of vitamin E to reverse changes caused by Cadmium intoxication in blood oxidative system, hemoglobin derivatives and electrical conductivity. The experiments were carried out on the Swiss albino rats which were orally administered Cadmium chloride (5mg /kg BW) and vitamin E (100mg/kgBW) by giving alone or in combination. The tested doses were given to rats every other day (15 times). The results revealed that treatment with cadmium chloride caused marked elevation in the level of lipid peroxidation (estimated by the amount of MDA) and a decline in SOD, GSHPx and CAT activities accompanied with an increase in the rate of hemoglobin autoxidation. The results also demonstrated a marked increase in hemoglobin derivatives as well as in hemoglobin electrical conductivity. Treatment with vitamin E significantly reduced the changes caused by Cadmium treatment in all examined parameters. These results indicate that alterations caused by Cadmium chloride are connected with free radicals generation and used antioxidant effectively protect against Cadmium intoxication.Journal of Applied Sciences Research. 01/2007; 3:437-443.
Article: Cadmium toxicity revisited: focus on oxidative stress induction and interactions with zinc and magnesium.[show abstract] [hide abstract]
ABSTRACT: Discovered in late 1817, cadmium is currently one of the most important occupational and environmental pollutants. It is associated with renal, neurological, skeletal and other toxic effects, including reproductive toxicity, genotoxicity, and carcinogenicity. There is still much to find out about its mechanisms of action, biomarkers of critical effects, and ways to reduce health risks. At present, there is no clinically efficient agent to treat cadmium poisoning due to predominantly intracellular location of cadmium ions. This article gives a brief review of cadmium-induced oxidative stress and its interactions with essential elements zinc and magnesium as relevant mechanisms of cadmium toxicity. It draws on available literature data and our own results, which indicate that dietary supplementation of either essential element has beneficial effect under condition of cadmium exposure. We have also tackled the reasons why magnesium addition prevails over zinc and discussed the protective role of magnesium during cadmium exposure. These findings could help to solve the problem of prophylaxis and therapy of increased cadmium body burden.Archives of Industrial Hygiene and Toxicology 03/2011; 62(1):65-76. · 1.05 Impact Factor