Documents biomarker 64 results

"The aim of this study was to investigate the possibility of subtoxic exposure to pesticides causing chromosome aberrations in greenhouse workers.In a cross-sectional and prospective study design chromosome aberration frequencies in cultured lymphocytes were examined for 116 greenhouse workers exposed to a complex mixture of almost 50 insecticides, fungicides, and growth regulators and also for 29 nonsmoking, nonpesticide-exposed referents.The preseason frequencies of chromosome aberrations were slightly but not statistically significantly elevated for the greenhouse workers when they were compared with the referents. After a summer season of pesticide spraying in the greenhouses, the total frequencies of cells with chromosome aberrations were significantly higher than in the preseason samples (P=0.02) and also higher than for the referents (P=0.05). This finding was especially due to an increased number of cells with chromatid gaps between the first and second samples (P=0.001). The results may reflect an additive genotoxic effect of the spraying season, for which the use of insecticides and growth regulators (but not fungicides) culminates. The highest elevation in the risk of chromatid gaps was observed for persons who did not use gloves during re-entry activities such as nipping, cutting, pricking, and potting (risk ratio 2.88, 95% confidence interval 1.63-5.11). The present results suggest a genotoxic effect from a complex subtoxic occupational pesticide exposure. In general, the findings indicate the importance of personal protection, during high-exposure re-entry activities, in preventing pesticide uptake and genetic damage. ... "

"Objectives The aims of the study were to assess renal function in chloralkali workers previously exposed to mercury vapor and to assess the impact of selenium status on the biomarkers of kidney function.Methods Forty-nine chloralkali workers previously exposed to mercury vapor were compared with 49 age-matched referents in a cross-sectional study. Selected biomarkers of kidney function and biomarkers of selenium status were measured. The index group had been exposed for 13.1 (range 2.8–34.5) years on the average at a mean urinary mercury excretion of 9.3 (range 4.0–25.4) nmol/mmol creatinine a year. The exposure had ceased on an average of 4.8 (range 4.2–10.0) years prior to the examinations. Results No statistically significant differences were found between the groups for the measured biomarkers of kidney function. The serum selenium concentration and serum glutathione peroxidase activity were associated with the activity of N-acetyl-ß-D-glucosaminidase in urine (U-NAG). The results indicate that having higher glutathione peroxidase activity or a higher serum selenium concentration results in a lower excretion of U-NAG. This effect was the most pronounced in the oldest third of the participants. Apparently the well-known association between U-NAG and age could only be found for the participants with a lower selenium status.Conclusions Increased activities of U-NAG during ongoing exposure to mercury vapor appear to be reversible upon cessation of exposure. Selenium status has a substantial impact on U-NAG activity and should be considered in studies of U-NAG excretion."

Objectives The effect of introducing regularity, few consecutive night shifts, more weekends off, and only 2 different types of shifts (day-evening or day-night) into shift scheduling on biomarkers of heart disease was studied.Methods Ergonomic shift criteria were introduced in a quasi-experimental controlled intervention in 4 hospital wards. Six wards participated as controls. Altogether 101 nurses and nurses' aides were followed for 6 months with measurements of cholesterol and triglycerides. The intervention led to more regular schedules and more staff having 2 shifts in 2 of the intervention wards 1 year after the intervention. The schedules among the controls became less regular and less predictable. The number of consecutive night shifts remained unchanged.Results After 6 months the high-density lipoprotein (HDL) cholesterol level had increased in the intervention group, and the total cholesterol and low-density lipoprotein (LDL) cholesterol levels and the total:HDL cholesterol ratio had decreased. Regardless of the intervention, changes in regularity were associated with the triglyceride and HDL cholesterol levels and also with the total:HDL cholesterol ratio. More ergonomic changes were associated with lower LDL cholesterol levels, a lower total:HDL cholesterol ratio, and higher HDL cholesterol levels.Conclusions Increased ergonomic scheduling was possible. Lipids and lipoproteins changed as predicted, both when the changes were assessed in respect to the changes in schedules that resulted from the intervention and the changes that occurred regardless of the intervention. The study suggests that scheduling based on ergonomic criteria is a possible means for reducing the risk of heart disease among shift workers.

"Objectives The aims were to study the toxicokinetics of 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) in blood and urine after exposure to N-methyl-2-pyrrolidone (NMP) and to study the suitability of 5-HNMP as a biomarker for assessing NMP exposure.Methods Six male volunteers were exposed for 8 hours to NMP concentrations of 0, 10, 25, and 50 mg/m3. Blood and urine were sampled before, during, and up to 40 hours after exposure. Aliquots of urine and plasma were purified, derivatized, and analyzed for 5-HNMP on a gas chromatograph/mass spectrometer in the electron impact mode.Results The mean plasma concentration [P-(5-HNMP)] after 8-hour NMP exposure to 10, 25, and 50 mg/m3 was 8.0, 19.6, and 44.4 mmol/l, respectively. The mean urinary concentration [U-(5-HNMP)] for the 2 last hours of exposure was 17.7, 57.3, and 117.3 mmol/mol creatinine, respectively. The maximal P-(5-HNMP)and U-(5-HNMP) concentrations occurred 1 hour and 0-2 hours, respectively, after the exposure. The half-times of P-(5-HNMP) and U-(5-HNMP) were 6.3 and 7.3 hours, respectively. The 5-HNMP urinary concentrations were 58% of the calculated retained dose. There was a close correlation (r) between P-(5-HNMP) (r=0.98) and U-(5-HNMP) (r=0.97) with NMP exposure.Conclusion 5-HNMP is an excellent biomarker for assessing exposure to NMP. Its plasma and urinary half-times (6-7 hours), the minimal risk for contamination during sampling in occupational settings, and the close correlation of P-(5-HNMP) and U-(5-HNMP) with NMP exposure makes 5-HNMP suitable for monitoring exposure to NMP. 5-HNMP in plasma is recommended."

"The social, legal and ethical implications of advances in biomarker indentification have been discussed by scholars and environmental researchers, but not by the "everyday" professionals and workers who may eventually make and be affected by decisions about their workplace applications. Through the use of a hypothetical scenario, this study introduced members of various professional and occupational groups to the potential uses of biomarkers research on biological monitoring in the workplace. The purpose was to obtain opinions about how events would proceed based on the scenario, leading to a broad discussion of potential uses and abuses of biomarker-based health monitoring. Six professionally homogeneous focus groups, comprised of 1) company health professionals, 2) third-party payers, 3) attorneys, 4) human resource managers, 5) non-unionized workers, and 6) unionized workers, participated in focus groups presented as "think-tank" discussions in Greenville and Charleston, S.C. Participants were given a fictitious "newspaper article" about the use of biomarker-based monitoring at a chemical plant and were asked to comment on what they thought would happen next. The discussion expanded to a general consideration of biological monitoring and its legal, social and ethical ramifications. Data was analyzed through the "immersion/crystallization" method. Few participants reported any knowledge of biological monitoring prior to the focus group session. Some had initial difficulty understanding the concept and how it differs from other means of measuring environmental risk. Although biological monitoring was previously unknown to many participants, occupational groups were relatively consistent in the issues they raised about its use in the workplace. In all groups, questions about potential discrimination against employees were raised. The general consensus was that the use of biomarker-based monitoring would result in conflict and litigation without regulations to protect employees from discrimination. Although most participants saw potential health benefits resulting from the preventive advantages associated with this technology, their concerns about its misuses were paramount. Perceptions varied as a function of occupation. Non-unionized workers expressed the most concern about discriminatory uses of biological monitoring. Unionized workers, who said they believed the union would support their interests, expressed much less concern. Health professionals (company physicians and nurse practitioners) were most alarmed about the "extra work" a monitoring program would create for them. Human resource managers concentrated on the company's "damage control" efforts. Attorneys emphasized that the reliable use of such tests would establish a causal relationship between exposure and personal injury. The results of this project illustrate that people who are most likely to be affected by biomarker-based biological monitoring in the workplace readily understand and are alarmed by its legal and ethical implications. It is unlikely that this technology will be fully accepted as an environmental risk assessment tool or as a prevention strategy without stringent protection of workers' rights. This study demonstrated the value of focus groups in obtaining opinion data about an environmental risk issue that it not yet well known to the general public."