Question

The damage to proximal tubular cells results in:

• A. Increased reabsorption of proteins
• B. Reduced reabsorption of proteins
• C. Increased excretion of low-molecular weight proteins
• D. Reduced excretion of low-molecular weight proteins

Answer 1

Answer:

C. Increased excretion of low-molecular weight proteins

• Kidney and bone are the critical target organs with regard to environmental exposure. The main critical effects include increased excretion of low-molecular weight proteins in the urine (as a result of proximal tubular cell damage) and an increased risk of osteoporosis.

• An increased risk of lung cancer has also been reported following inhalation exposure in occupational settings.

• The margin of safety between the present daily intake of cadmium in the diet and the intake that can result in effects is very narrow and, for highly exposed sub populations, even non-existent.

• Population groups at risk include the elderly, people with diabetes, and smokers. Women may be at increased risk because they have lower iron stores than men and, consequently, absorb more cadmium at the same level of exposure.

• Food is the main source of cadmium exposure in the general population (representing >90% of the total intake in non-smokers).

• In heavily contaminated areas, dust resuspension can constitute a substantial part of the crop contamination and exposures via inhalation and digestion.