No abstract

The living place of parents, mother who feed pets before pregnancy, exposure to harmful chemicals of father before pregnancy were the risk factors of retinoblastoma which affects the occurrence of retinoblastoma in a certain extent.

Objectives High-speed Maglev transportation system is an advanced technology using magnetic forces to propel, levitate, and guide the trian. Our study was to assess the EMF emitted by High-Speed Maglev Transportation System and the possible health effects of occupational exposure to the Maglev EMF. Methods The static magnetic field of Maglev were measured by Narda ETM-1 magnetic field measurement system. The time-varying EMFs of Maglev were evaluated by PMM8053 EMF measurement system. 48 employees exposed to maglev EMF were selected as occupationally exposed group while 54 employees without any Maglev EMF exposure were selected as control. Questionnaires were sent to two groups. Complete blood count was done by haematology analyzer. Blood lipid level was detected by enzymatic method. Thyroid function related hormones was evaluated by chemical immune assay. Serum melatonin level was measured by an ELISA kit. Results EMF strength of all Maglev sites was lower than the safety exposure limits of current international and Chinese national standard. The symptoms of drowsiness, memory impairment, irritability, alopecia were related to occupational exposure to maglev EMF. Abnormal rate of cholesterol and high density lipid protein in exposed group were significantly higher than control. The blood cell counts, thyroid function, and serum melatonin level had no statistical difference between two groups. Conclusions EMF emitted by the High-speed Maglev transportation system in different frequencies were lower than the exposure limits of current international and Chinese national standard. Due to the population limits, we can not draw a conclusion that occupational exposure to Maglev EMF may have adverse health effects from the previous data. However, it may gives us a clue that occupational exposure to maglev EMF may result in the alteration of neuronal function and lipid metabolism.