Objective  To investigate the health damage caused by long-term exposure to low-intensity laser among female workers and provide a basis for the development of corresponding preventive measures.

  Methods  Totally 96 female workers exposed to low-intensity laser in a large-scale communication equipment manufacturing company were selected as the exposed group, while another 96 female office staff without any exposure to occupational hazards in the same company were studied as the control group. Occupational health examinations were conducted for all study participants, and the relative results were analyzed.

  Results  The prevalences of self-reported ophthalmic symptoms such as eye pain, foreign body-like irritation of the eye, photophobia, tearing, conjunctival congestion, and decreased visual acuity were higher in the exposed group than in the control group(P < 0.05). The prevalences of abnormalities in cornea, conjunctiva, lens, and fundus examinations were higher in the exposed group than in the control group(P < 0.05). The prevalences of self-reported dizziness, nausea, palpitation, insomnia, appetite loss, muscular stiffness, hypomnesis, hidrosis, feeling fatigued, and dysphoria were all significantly increased in the exposed group compared with the control group(P < 0.05). Rates of sinus arrhythmia and T-wave elevation in the exposed group were higher than those in the control group(P < 0.05). The menstrual abnormality in the exposed group was higher than that in the control group(P < 0.05). There was no statistically significant difference in abnormalities of blood pressure, blood routine examination, liver function, urine routine examination, and blood lipids between the exposed group and the control group(P > 0.05).

  Conclusions  Long-term exposure to low-intensity laser could at least cause damage to the eyes, nervous system, cardiovascular system, and reproductive system of female workers. Workers occupationally exposed to lase should pay attention to strengthening personal eye and skin protection.