الفهرس | Only 14 pages are availabe for public view |
Abstract There has been a growing awareness of the relationship between different types of the work and incidence of disease. With the increasing interaction between workers and mechanical tools, vibration at critical frequencies and acceleration has become an important source of injury. Occupational exposure to vibration arises in many different ways, reaching the subject at levels that may disturb comfort, health, safety, and efficiency. Occupational vibration is divided into two types, general or whole body vibration (WBV), which acts on the body of sitting or standing persons through transport the vibration from its source to the supporting surfaces at which the person exist. Local vibration or hand-arm vibration (HAV), which is mainly transmitted to hands and arms; and sometimes it is called segmental vibration. There are many factofl; that affect types of occupational vibration exposure, which include physical factors, biodynamic factors and individual factors. Aim of the study The present .work has been carried out .in. a trial to find a relationship between occupational exposure to vibration (WBV or HAV) and levels of some biochemical and haematological parameters. Materials aud methods A total number of 165 male workers have been selected for this purpose: 77 workers from Mousahama El - Behera company where the workers work in Toshka and exposed to WBV, 27 workers from Zahran company where the workers were exposed to HAV. A comparison group of 61 workers were selected from the previous compames with the same demographic characteristics, like age, . education status, socioeconomic status etc. as the exposed workers. Vibration readings were taken from the two companies. Fasting blood samples were collected from each of the examined subjects using the vein puncture technique. Part of the blood was added to the EDTA for haematological analysis [Hb, Ht value, RBCs, WBCs, PLT count, MCV, MCH and MCHC], other part was added to sodium citrate for determination of Proth and Fib. The rest of blood was allowed to clot at room temperature and the serum was separated then analyzed for lipid [Ch, TG, HDL and LDL], some’ liver and cardiac enzymes [SGPT, SGOT, LDH and CPK], some trace elements [Cu, Zn, Mg and Mn], and U.T.Catech. Examination ofBT and CT were done by using standard technique. Also spot urine samples were collected. Lipid, Hb and enzymes in serum were performed using spectrophotometer. Also trace.. elements analyses m serum were performed using an atomic absorption spectrophotometer and applying the standard instrumental conditions for the determination of each of the trace elements. The U.T.Catech. was performed using fluorescence spectrophotometer. The collected data were coded and transferred to special coding sheets. Calculations of the statistics of the present study have been done and the data were statistically analyzed using ANOVA test and Pearson’s correlations. Results The determination of the indices of exposure revealed that workers exposed to V had higher values of MCH, Proth time, SGPT, SGOT, LDH, CPK; Cu, Zn, Mg, Mn and U.T.Catech; and lower values ofRBCs, PLT count, CT and HDL when compared with the values of control group. Furthennore, HAV exposed workers has higher values of Proth time, LDH, CPK; Cu, Mg, Mn and U.T.Catech; and lower value ofHb, Ht value, RBCs, and PL,T count when compared with the values of · control group. On the other hand, WBV exposed workers had higher values of SGPT, SGOT and Mn; and lower values ofHDL and Mg when compared with the values ofHAV exposed workers. Pearson’s correlations test revealed that, workers exposed to WBV show positive correlation between Cu and each of Hb, Ht value, MCV, MCH, Ch, SGPT and SGOT; and negative correlation between Cu and each ofLDH and CPK. There is also positive correlation between Zn and Ch; and negative correlation between Zn and each ofHb and TG. On the other hand, Mg correlates positively with Ht value and HDL; and negatively with LDL. Concerning Mn, there is positive correlation with Hb and Ht value, and negative correlation with U.T.Catech. Prothrombin time shows positive correlation with SGPT and SGOT; and negative correlation with Fib. Fibrinogen also shows negative correlation with SGPT. Furthermore, each of Ch and TG correlate positively with LDH and CPK; and LDH correlate positively with CPK. Finally, U.T.Catech. correlates negatively with Ch and HDL. Concerning workers exposed to HAV, there is positive correlation between Cu and each of Hb, Ht value, RBCs, MCV, MCH, Ch, SGPT, LDH and CPK. Zinc correlate negatively with Hb and RBCs. On the other hand, Proth time correlate positively with SGPT and SGOT. Also CPK correlate positively with HDL. Finally U.T.Catech. correlates positively with SGPT and negatively with Mn. Conclusion It has been concluded that exposure to occupational vibrations · (WBV or HAV) may exert some occupational disease through disturb some haematological and biochemical parameters by direct alteration of the levels of some liver and cardiac enzymes; and through its interference with some trace elements metabolism leading to changes in some haematological and lipid parameters. Furthermore, occupational vibrations influence the level of U.T.Catech. through direct or indirect mechanisms; these changes may cause cardiovascular disease. Recommendations from the previous results, we an recommended may preventive measures - to protect workers occupationally exposed to WBV or HAV - like choosing an appropriate method to minimizing vibration exposure; and make a system for medical screening (pre and periodic medical examinations) for workers including haematological and biochemical tests. Employers must use rest periods for workers exposed to occupational vibration to minimize total time of vibration exposure. Also employers must do periodic and preventive maintenance for machine generating vibration. On the other hand, employees must be advised for occupational vibration risk and encourage them to report any side effects occurring like low- back pain or finger blenching. In addition to the prev10us preventive measures, workers occupationally exposed to HAV must protect their bodies from cold temperatures with. prote. ;:ting their hands from injuries. Also they must avoid tobacco since nicotine cause poor blood circulation in the fingers. |