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The Subcommittee on Cadmium of the IUPAC Clinical Chemistry Division's Commission on Toxicology performed two cooperative interlaboratory surveys in 1983 and 1985. In the first survey, performed in 1983 with liquid human and lyophilized synthetic urines, 35 laboratories from 13 countries participated. In the second survey, performed in 1985 with two liquid and four lyophilized human urines, 32 laboratories from 16 countries participated. Due to recent instrumental improvements most laboratories were able to apply direct GFAAS determination methods either with deuterium or Zeeman background correction with acceptable results even at lower levels. However, as has already been observed for cadmium in whole blood surveys, there were still problems with samples having cadmium levels above 15 μg/l which certainly need further investigations [1]. The results of both surveys clearly indicate that materials based on human urine, either liquid or lyophilized, are the most promising for intra- and interlaboratory quality assessment studies. The main goal of the surveys was to check whether a candidate standardized method could be established.

The Subcommittee on Cadmium of the IUPAC Clinical Chemistry Division's Commission of Toxicology performed two cooperative interlaboratory surveys from 1979 to 1981 for the determination of cadmium in whole blood. The goal was to study the suitability of a possible standardized method. This paper presents the results of two pilot studies and the two surveys for cadmium in blood. The first survey (1979 to 1980) involved 21 participants from 10 countries; the second (1981) 30 participants from 14 countries. Significant improvements in the ability to analyze endogenous concentrations of cadmium in blood occurred in the 14 laboratories which participated in both surveys. However, most participants experienced difficulty in analyzing concentrations higher than 15 μg/l. It was concluded the suggested standardized method gives a better precision and fewer outliers if compared with other methods.

The DEC Clini Lab — 12 System of the Montreal General Hospital is described. The reasons for selecting it are given and brief comparisons are made with two other rather similar commercial systems. Some insight is given into installation problems.

1. The Pearson, Stern, and McGavack method for the determination of cholesterol was found to be rapid and suitable for routine clinical purposes. It gave, within experimental error, total cholesterol values in agreement with the method of Bloor. 2. A proposed modification of the method, providing for a final volume of 6.3 ml., and a shorter operational time, was found to give values in excellent agreement with the original method. 3. Sulfosalicylic acid may be used as a substitute for p-toluenesulfonic acid. However, no evidence of the excessive reactivity reported from one source has been experienced at any time in this laboratory with the p-toluenesulfonic acid reagent. 4. Similar optical densities were obtained from equimolar quantities of cholesterol and cholesteryl palmitate when the Pearson, Stern, and McGavack method was used. 5. Serum cholesterol values for 61 normal males were found to range from 150 to 320 mg./100 ml. of serum.

We assessed the reported presence of creatine kinase-BB isoenzyme in the serum of patients with chronic renal failure. Our study showed that the blood of these patients contains a fluorescent material with an electrophoretic mobility similar to that of the BB isoenzyme on cellulose acetate strips. The fluorescing material is, however, completely distinct from BB isoenzyme and its nature is as yet undetermined.

The levels of glycosylated hemoglobin (GlHb), fasting plasma glucose (FPG), urine glucose, serum triglycerides, cholesterol, and HDL-cholesterol were monitored in several hundred patients attending an adult diabetic clinic. Thirty-five percent of the patients were being treated with insulin, 30% with diet alone, and 20% with sulfonylurea. Therapy was changed during the study in the remaining 15%. The levels of GlHb and FPG were significantly lower in the patients treated with diet alone than in the other groups. The overall coefficient of correlation (r) between FPG and GlHb was 0.64, with the highest r (0.70) for the diet group and the lowest r (0.55) for the insulin group. A follow-up study showed that in about 50% of the patients GlHb and FPG levels changed in different directions from one visit to the next. The absence of glycosuria was noted in two-thirds of the patients, while in 78% of the patients GlHb values were above the normal range. A weak but positive correlation was found between GlHb and serum triglycerides and cholesterol. There was no significant correlation between GlHb and HDL-cholesterol. The HDL-cholesterol levels were significantly lower in male than in female diabetic subjects, but no significant difference was found between the diabetic and nondiabetic subjects of the same sex. The results of this study suggest that (1) although there is a positive correlation between GlHb and FPG, the two tests cannot be used interchangeably in the evaluation of diabetic control; and (2) in the majority of the patients the absence of glycosuria tends to create the false assurance of satisfactory blood glucose control.

The Cadmium Subcommittee of IUPAC (Chairman M. Stoeppler, Julich), Clinical Chemistry Division, Commission on Toxicology was established 1978 and a first meeting held in Kristiansand, Norway. The subcommittee aims predom-inantly at assessing, improving and harmonizing analysis of cadmium in biopsy and autopsy materials and of other biochemical parameters useful for response studies in cad-mium exposure investigations.

We assessed the reported presence of creatine kinase-BB isoenzyme in the serum of patients with chronic renal failure. Our study showed that the blood of these patients contains a fluorescent material with an electrophoretic mobility similar to that of the BB isoenzyme on cellulose acetate strips. The fluorescing material is, however, completely distinct from BB isoenzyme and its nature is as yet undetermined.

Fig. 1 and 2, pp. 761 and 762 were erroneously interchanged. The Figure of p. 762 should be Fig. 1, the Figure of p. 761 Fig. 2.