Relationship between liver function indicators and exposure time among male workers occupationally exposed to hepatotoxic substances

Objective  To understand the liver function status of male workers occupationally exposed to hepatotoxic substances and to explore the relationship between liver function indicators and exposed hazards, providing a basis for formulating reasonable health monitoring plans and effective protective measures.

Methods  Health examination data of male workers engaged in work related to hepatotoxic substances from 2013 to 2021 at a certain occupational disease prevention institution in Shanghai was collected. The occurrences of various liver function indicators and their relationship with age or exposure time were studied.

Results  Over 9 years, 92 788 male workers were examined. The exposure time of these workers occupationally exposed to hepatotoxic substances ranged from 0.5 to 45.0 years, with a median value of 5.0 years. A total of 52 096 workers were tested for all 8 liver function indicators. The abnormality rates of each liver function indicator were as follows: ALT 22.7%, AST 4.4%, TP 0.0%, ALB 0.5%, TBIL 44.2%, DBIL 16.9%, GGT 15.7%, and ALP 4.2%. Overall, the indicators ALT, AST, and GGT showed an increasing trend with years of service (r = 0.045-0.155, P < 0.05), with GGT having the strongest correlation with years of service. DBIL and ALP showed a decreasing trend with years of service (r = -0.180, -0.033, P < 0.05). There was no significant correlation between years of service and TBIL levels (P > 0.05). After age stratification, most age groups still showed a correlation between liver cell damage indicators (ALT, AST, GGT, and ALP) and years of service; in the younger age group, the correlation between AST, GGT, and ALP with years of service was consistent with the overall results; in the older age group, the correlation was no longer significant. The correlation between the liver synthesis and metabolism indicator DBIL and years of service only appeared in the 18-29 age group.

Conclusions  With proper protection, long-term, low-level exposure to hepatotoxic substances does not cause severe health damage to workers. However, as years of service increase, there is still potential for liver function impairment. Enterprises need to standardize operating procedures, ensure exposure levels are below the national exposure limits, and protect the health of workers.