To explore the correlation of peripheral blood 5-hydroxytryptamine (5-HT) levels with vibration exposure levels and peripheral vascular damage in hand-arm vibration exposed workers.

Seventy-seven workers exposed to hand-arm vibration from a sports equipment manufacturing company in Guangdong were selected for this study. General in formation, upper limb symptoms, and vibration-induced white finger (VWF) of the workers were collected by questionnaire. Cumulative vibration exposure level (CVEL) was calculated through on-site tested hand-arm vibration levels of the selected workers. Level of 5-HT in peripheral blood was detected by enzyme-linked immunosorbent assay. Cool water loading test (CWLT) was also conducted for the workers. The association of 5-HT level with hand-arm vibration exposure level and peripheral vascular damage was analyzed using binary non-conditional logistic regression models.

The high CVEL group showed a higher 5-HT le vel than the low CVEL group (z=-2.352, P=0.034). The 5-HT level in the abnormal CWLT group was much higher than that in the normal CWLT group (z=-3.211, P=0.001). After adjusted for age, smoking, and drinking, according to the logistic regression model, 5-HT level was associated with CVEL and CWLT:ORs (95%CIs) were 3.17 (1.12, 8.94) for high CVEL vs. low CVEL and 7.34 (1.44, 37.30) for abnormal CWLT vs. normal CWLT. The 5-HT level was not correlated with VWF results with OR (95%CI) as 1.92 (0.74, 5.00).

The results suggests that hand-arm vibration exposure might result in elevated 5-HT levels, and the level of 5-HT correlates to vibration exposure level or hand peripheral vascular damage degree.