Study on fibrosis changes in the lungs of mice caused by repeated inhalation of polyhexamethyleneguaidine disinfectant / 中华预防医学杂志

Objective@#To explore the lung damage caused by repeated inhalation of polyhexamethyleneguanidine (PHMG) disinfectant aerosol and the corresponding toxicological characteristics.@*Methods@#Thirty four-week-old mice of C57BL/6N strain were randomly divided into three groups, the control group, low-dose group, and high-dose group. Each group had 5 male mice and 5 female mice. Lab II-level purified water was used in the control group. The PHMG disinfectant aerosol was generated by using the ultrasonic atomization of the aqueous solution containing PHMG. The PHMG concentrations in the low-and high-dose groups were 0.1 mg/ml (0.01%) and 1 mg/ml (0.1%), respectively. The concentration of PHMG in the post-chemical exposure room was 1.03 mg/m3 and 9.09 mg/m3 according to the air sampler analysis. The experimental mice were exposed to the PHMG in dynamic respiratory exposure mode for 4 hours every day in 21 days. After 21-day exposure, bronchia alveolus lung fluids (BALFs) were used to evaluate the inflammatory cells in the lungs, and pathological evaluation, special staining and immunohistochemical methods were further performed to evaluate the key indicators of pulmonary fibrosis.@*Results@#Compared to the control group, the body weight of mice in the high-dose group was significantly decreased (P<0.05), while that of mice in the low-dose group did not significantly differ (P>0.05). The number of inflammatory cells in BALFs of low-dose exposed mice was slightly reduced, and the lung tissue pathology began to show lung damage with early fibrosis symptoms (P<0.05). The pathological examination of mice in the high-dose group showed changes in pulmonary fibrosis. Immunohistochemical staining showed that pulmonary fibrosis marker, α-SMA, was significantly increased in low-dose group and high-dose group (P<0.05).@*Conclusion@#The repeated inhalation of PHMG disinfectant could cause lung damage such as pulmonary fibrosis in mice. It could suggest that special warnings should be given to this common disinfectant and respiratory protection measures should be adopted during industrial production and daily use.

The relationship between hemoglobin adducts of trinitrotoluene and exposed level / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the biomarkers for monitoring trinitrotoluene (TNT) exposure, the relationship between TNT hemoglobin adducts and TNT exposed level.</p><p><b>METHOD</b>Hemoglobin adducts (4A-Hb and 2A-Hb) were determined by GC-MS in 25 TNT exposed workers. TNT exposed level was evaluated by determining skin contaminated and inhaled TNT levels. The correlation between hemoglobin adducts level and TNT exposed level was analyzed.</p><p><b>RESULTS</b>There was a correlation between total TNT exposure level, especially skin exposure level, and 4A-Hb or 2A-Hb content. No significant difference was found between the slopes and intercepts of lin ear equation of (4A-Hb) vs TNT exposed level and linear equation of (4A-Hb +2A-Hb) vs TNT exposed level (P > 0.05).</p><p><b>CONCLUSION</b>Skin contamination is the major role of TNT exposure. TNT exposed level can be evaluated by determining the content of both 4A-Hb and 2A-Hb, and 4A-Hb is more suitable for monitoring TNT exposure.</p>

A molecular epidemiological study of childhood lead poisoning in lead-polluted environment / 中华流行病学杂志

<p><b>OBJECTIVE</b>The relationship between polymorphisms of ALAD and VDR genes and individual susceptibility of lead poisoning was investigated in children highly-exposed to lead.</p><p><b>METHOD</b>Four hundred and sixty-nine children were recruited into this study and the blood lead, ZPP, hemoglobin as well as three physical developmental indexes (head circumference, height and weight) were measured. VDR and ALAD gene polymorphisms were analyzed by the methods of PCR-RFLP.</p><p><b>RESULTS</b>The subjects with ALAD2 allele had higher ZPP level (10.12 micro mol/L vs 12.87 micro mol/L) (P = 0.017). The subjects with B allele has larger head circumference than only with b allele (51.19 cm vs 50.75 cm) (P = 0.028).</p><p><b>CONCLUSIONS</b>It was suggested that the ALAD gene polymorphism modified the relationship between blood lead and ZPP and the VDR gene variants influenced the skull development in children living under lead-polluted environment. The polymorphism of ALAD and VDR genes might serve as the molecular inherited factors modifying the susceptibility of lead poisoning.</p>