STANDARDIZED METHOD FOR THE ESTIMATION OF BETA(2)-MICROGLOBULIN, RETINOL-BINDING PROTEIN AND ALBUMIN IN URINE (REPRINTED)

Increased excretion of proteins in urine are early signs of exposure of subjects of the general population and in occupation to xenobiotics. These signs are parameters of an early effect on the kidney and may be used as biological effect parameter. Xenobiotics who may cause such effects are metals such as cadmium and lead, solvents as toluene and styrene, and some pesticides. Effects on the kidney tubuli are responsible for e.g. enhanced beta-2 n-microglobulin and retinol binding protein concentrations in urine; effects on the glomeruli for albumin in urine. Standardization of methods to determine physiological concentrations will be necessary to compare the results of epidemiological studies. A protocol for such methods is described in which the proteins beta-2 microglobulin retinol binding protein and albumin are determined routinely. Also, a calibration curve program is presented. The results of several comparison studies show that the methods described in this report are reasonably to well comparable between different laboratories.