Evaluation of the current risk of lead poisoning in the ceramics industry.

Evaluation of the current risk of lead poisoning in the ceramics industry. Scand j work environ health 9 (1983) 463-469. The authors evaluate the current possibility of lead poisoning in the production of ceramic tiles, an industrial sector which has always been considered dangerous due to the use of lead-rich glazes. The study was conducted in nine plants, four of which were repeatedly monitored (five checks on 94 exposed subjects). The other five plants (for a total of 221 exposed subjects) were only checked once. An analysis of all the results showed a clear reduction in mean blood lead levels, which the authors believe was due to the use of glazes with less lead. The results obtained were generally satisfactory; they indicated a definite improvement in the situation with respect to the authors' previous investigations, even for jobs in which workers were more frequently exposed. The data overlap those observed in the production of artistic pottery, which has always been considered less dangerous.

The ceramics industry and lead poisoning. Lead poisoning in relation to technology and jobs.

The investigation evaluates the risk of lead absorption for 288 ceramics industry workers. Cases were studied in relation to sex, type and length of exposure, production plant characteristics, and jobs performed. The difference linked with sex was amplified by the fact that men usually performed the decidedly higher risk jobs, such as those connected with the direct use of ceramic glazes, in which--although to a variable extent--high percentages of lead are used. In fact, decreasing amounts of lead absorption were found for workers engaged in the operations of glazing, kiln work, maintenance and decoration, selection coming last. It was concluded that, in the Italian ceramics industry, lead exposure is linked to the use of lead-rich glazes and that this exposure may thus vary according to the different jobs or different technological cycles. Although female workers primarily carry out decoration and selection jobs, they nonetheless show high levels of lead in their blood, exceeding 1.9 mu mol/l--the limit currently recommended for women.

[Urinary excretion of mutagens and cisplatin among the nursing staff at a medical oncology department exposed to cytostatic drugs]. / Escrezione urinaria di mutageni e cisplatino nel personale infermieristico dei reprti di oncologia media esposto a farmaci citostatici.

Exposure to cytostatic drugs was assessed in a group of 9 nurses employed in a hospital cancer therapy department by measuring the post-shift levels of urinary mutagens and cis-platinum. A slight but significant increase in urinary mutagenic activity compared to 11 controls was observed in the non-smokers: the mean values of mutagenic activity on the Ta100 strain in the presence of both microsomal and deconjugating enzymes were 4418 +/- 1186 and 2468 +/- 1681 respectively. Conversely, the urinary platinum concentration was below the detection limit of the analytical method (10 micrograms/l) in all samples. The increased urinary mutagenic activity in the exposed group can probably be attributed to the absorption of cyclophosphamide either during preparation and administration of the drug, or due to accidental contact with contaminated biological fluids, in view of the fact that the level of mutagens in urine samples from cyclophosphamide-treated patients is extremely high (up to 319,478 revertants/g creatinine in the case we examined).

Biological monitoring of nitrous oxide exposure in surgical areas.

Exposure to nitrous oxide in surgical theaters was evaluated for duration, numbers, and types of surgical procedures. The concentration of the gas in the air was 92-444 ppm. Before and after the surgical sessions, samples of urine and expired air were collected from surgical theater personnel for gas determination. Nitrous oxide concentrations in urine and in expired air showed a good correlation with gas concentration in the air (r = 0.760 and r = 0.921, respectively). Moreover, a good correlation (r = 0.823) between gas concentration in urine and that in expired air was also found. A biological threshold limit value (TLV) of 20.6 micrograms/liter for urine and of 29.6 ppm for expired air was calculated, based on the limit of 50 ppm in the air proposed by the American Conference of Governmental Industrial Hygienists (ACGIH). Other biological TLVs corresponding to higher proposed limits (200 and 500 ppm) were also calculated.

Postulated mode of action of lead on aminolevulinic acid dehydratase in chronic exposure.

The authors studied in vitro the variations of erythrocyte ALA D activity in subjects exposed and not exposed to lead risk before and after three tests: heat treatment at 60 degrees C for five minutes, addition of GSH (1 X 10(-2) mol/l) and of zinc (1.5 X 10(-4) mol/l). A study of the ratios before and after treatments showed that GSH and zinc were better than heating in identifying false positives, and that zinc was preferable, owing to lesser dispersion of results around the mean. The ratios of ALA D activity before and after treatment is more closely correlated with PbB levels than ALA D activity without treatment. The addition of GSH restored the enzyme activity of the exposed subjects to values equal to those obtained with heating; this did not happen in the non-exposed subjects. It is postulated that, in lead exposure, the metal acts only on the thiol groups, which may then be reactivated by an optimal concentration of GSH.

Site of action of metals on the aminolevulinic acid dehydratase of human erythrocytes.

The site of action of four metals (copper, lead, nickel and zinc) on the aminolevulinic acid dehydratase of human erythrocytes was studied. Data obtained after denaturation of allosteric sites with heat treatment and after simultaneous incubation with two metals suggest the following conclusions: copper acts on the catalytic site, whereas lead, nickel and zinc act on the allosteric sites; zinc and nickel act on the same allosteric (metallic) site; zinc and lead only partially act on the same metallic site; nickel and lead act on different allosteric sites.

[Evaluation of exposure and of the biological effects in galvanic chromium plating by different technologies]. / Valutazione dell'esposizione e degli effetti biologici nella cromatura galvanica a diversa tecnologia.

In the hard electroplating process, chromium exposure is heavier than in the bright process. The average urinary chromium was 9,7 +/- 7,2 micrograms/g cr. in the 31 bright plating subjects; comparing only the chromium bath workers of the two process, the difference was statistically significant (13,0 +/- 7,5 micrograms/g cr. against 7,6 +/- 4,4 micrograms/g cr. t = 2,4; p less than 0,0025). In a control group composed of 22 sanitary workers, the average urinary chromium was 1,9 +/- 1,4 micrograms/g cr. We found chromium rhinopathy in 40% of the hard process subjects and in 20% of the bright process subjects. Sputum cytologic examination was not correlated with the chromium level exposure. In the exposed workers we found 37% insufficient specimens and 53% metaplasia plus dysplasia; in the 42 control subjects we found 64% insufficient specimens, 33% metaplasia and no dysplasia.

The validity of urinary metabolites as indicators of low exposures to toluene.

Exposure to toluene was studied in a group of 14 subjects working in a printing industry, who were exposed to this solvent only. Environmental monitoring was carried out using personal samplers for the whole workshift over three consecutive days. Toluene TWA concentrations ranged from 37 to 229 mg/m3. At the end of the workshift on each day of investigation, urine samples were collected for the determination of hippuric acid and ortho-cresol. Hippuric acid was also determined for urine before the workshift and on the Saturday and Monday mornings after the end of exposure; hippuric acid was also determined in 16 controls over the same five-day period. At the end of the workshift, hippuricuria levels in exposed workers always turned out to be statistically different from pre-workshift levels and those of the controls. The end-of-workshift hippuricuria levels of exposed workers were significantly correlated with the mean daily environmental concentration (TWA): in the three days of comparative study, we found r = 0.63 (P less than 0.05) on Day 1, r = 0.90 (P less than 0.001) on Day 2, and r = 0.87 (P less than 0.001) on Day 3. Ortho-cresol turned out to be correlated with daily exposure less significantly than hippuric acid: r = 0.49 (n.s.) on Day 1; r = 0.78 (P less than 0.001) on Day 2, and r = 0.65 (P less than 0.05) on Day 3. Using all available data (41 observations), a very significant correlation (P less than 0.001) was found between the TWA and both metabolites (r = 0.80 for hippuric acid; r = 0.68 for o-cresol). The values of the two metabolites in the end-of-workshift urine samples (41 observations) also turned out to be well correlated (r = 0.70; P less than 0.001). The authors conclude that hippuric acid is a valid test for evaluating even low exposures to toluene.