Evaluation of chemical-specific IgG antibodies in male workers from a urethane foam factory

Background: Plastic resins are complex chemicals that contain toluene diisocyanate (TDI) and/or trimellitic anhydride (TMA), which cause occupational allergies (OA), including respiratory allergies. Serum IgGs against TDI and TMA have been suggested as potential markers of the exposure status and as exploring cause of OA. Although TDI-specific IgG has been examined for suspected OA, TMA-specific IgG is not commonly evaluated in a urethane foam factory. This study therefore investigated both TDI- and TMA-specific IgGs in suspected OA patients and to evaluate the usefulness of the measurement of multiple chemical-specific IgG measurement for practical monitoring. Methods: Blood samples were collected from two male workers who developed respiratory allergies supposedly caused by occupational exposure to TDI and/or TMA for the presence of TDI- and TMA-specific IgGs. In addition, blood samples from 75 male workers from a urethane foam factory, along with 87 male control subjects, were collected in 2014 and tested for the same IgGs in 2014. The presence and levels of TDI- and TMA-specific serum IgGs were measured using dot blot assays. Results: We found that controls had mean concentrations of TDI- and TMA-specific IgGs of 0.98 and 2.10 μg/mL, respectively. In the two workers with respiratory allergies, the TDI-specific IgG concentrations were 15.6 and 9.51 μg/ mL, and TMA-specific IgG concentrations were 4.56 and 14.4 μg/mL, which are clearly higher than those in controls. Mean concentrations of TDI- and TMA-specific IgGs in the factory workers were 1.89 and 2.41 μg/mL, respectively, and are significantly higher than those of the controls (P < 0.001 and P < 0.026 for TDI- and TMA-specific IgGs, respectively). Conclusion: The workers suspected of OA showed an evidently high level of TDI- and TMA-specific IgG, and these levels in workers at the urethane foam factory were also significantly higher than those in controls. In conclusion, the measurement of TDI- and TMA-specific IgG among workers using plastic resins is helpful to monitor their exposure status.This study was funded by an Industrial Disease Clinical Research Grant (grant number 14040101-02 to M.T.) and the JSPS KAKENHI (grant numbers 22790546 and 25860472 to M.T.)

Determination of Chemical-Specific IgGs in Serum by an Enzyme-Linked Immunosorbent Assay With Partial Peptides of Human Serum Albumin

Many different types of chemicals are used in industry, and occupational allergies are becoming a serious problem in the field of industrial hygiene. In this study, we employed a novel enzyme-linked immunosorbent assay (ELISA) with partial peptides of human serum albumin (HSA) to quantify chemical-specific immunoglobulin G (IgG) in serum for evaluating exposure to chemicals. When HSA partial peptides containing lysine residues were mixed with formaldehyde (FA) or phthalic anhydride (PA), almost all lysine residues were lost. Mass spectrometry revealed that PA and FA formed imine and tertiary amine, respectively, with lysine residues in the peptides. Thus, we used FA- or PA-peptide adducts as an artificial antigen to detect FA- and PA-specific IgGs in serum. The concentrations of FA- and PA-specific IgGs in workers at plants utilizing plastic resins were significantly higher than those in general subjects. This method can estimate exposure levels to chemicals and thus be expected to contribute to the diagnosis of allergies in workers and to the prevention of health hazards due to harmful chemicals.This work was partially supported by grants from the Ministry of Education, Culture, Sports, Science and Technology, Japan, KAKENHI for Y.I. and M.T. (Nos. 17HO4714 and 17KO9174), a grant from Hiroshima University Industry-Academia Collaboration Program for Y.I. and an Industrial Disease Clinical Research Grant to M.T. This manuscript has been checked by a professional language editing service(American Journal Experts)

The respiratory effects of toner exposure according to long-term occupational toner handling history: A longitudinal analysis, 2004–2013

Objectives This report shows the relationship between toner exposure and respiratory effects for individuals with a longterm occupational toner-handling history, from 2004 to 2013. Material and Methods Authors studied 752 Japanese male workers in toner handling workshops. A total of 673 men who participated in an annual monitoring survey were analyzed in this study. The following monitoring was performed in the same season each year: personal exposure measurements, biological markers, respiratory function tests, a chest X-ray, chronic respiratory symptoms and incidences of respiratory diseases. To evaluate the toner exposure effect, the exposure categories suitable for each evaluation index were established. Results For those with an occupational toner-handling history, the mean occupational toner-handling period was 14.36 years (standard deviation = 6.62); one participant had 35 years of exposure, which was the longest and one participant had 1 year of exposure which was the shortest. There were no statistically significant differences in the rate of change of respiratory function tests. An ANOVA conducted on blood and urine test results showed that statistically significantly differences were observed for a few items but all the values were very low and within the standard range. Conclusions Authors conducted a 10-year ongoing study, but no obvious negative influences on health were attributed to toner exposure. In a work environment where adequate administrative controls are in place, personal toner exposure levels may be expected to be low, with no adverse effects on human health. Int J Occup Med Environ Health 2018;31(6):809–82

Risk Factors for Early Mortality in Older Patients with Traumatic Cervical Spine Injuries—A Multicenter Retrospective Study of 1512 Cases

For older patients with decreased reserve function, traumatic cervical spine injuries frequently lead to early mortality. However, the prognostic factors for early mortality remain unclear. This study included patients aged ≥65 years and hospitalized for treatment of traumatic cervical spine injuries in 78 hospitals between 2010 and 2020. Early mortality was defined as death within 90 days after injury. We evaluated the relationship between early mortality and the following factors: age, sex, body mass index, history of drinking and smoking, injury mechanisms, presence of a cervical spine fracture and dislocation, cervical ossification of the posterior longitudinal ligament, diffuse idiopathic skeletal hyperostosis, American Spinal Injury Association Impairment Scale, concomitant injury, pre-existing comorbidities, steroid administration, and treatment plan. Overall, 1512 patients (mean age, 75.8 ± 6.9 years) were included in the study. The early mortality rate was 4.0%. Multivariate analysis identified older age (OR = 1.1, p p = 0.009), cervical spine fracture (OR = 4.2, p p p < 0.001) as risk factors for early mortality. Older age, male sex, cervical spine fracture, complete motor paralysis, and chronic kidney disease are prognostic factors for early mortality in older patients with traumatic cervical spine injuries