The present study included the determination of the effect of continuous exposure to high temperatures on a number of hematological variables of a group of male workers exposed to occupational pressure in bakeries. The study included 50 workers exposed to heat and 20 volunteers as a control group. The workers group was divided into three age groups (15-25, 26-35, -36-50 year) according to their annual exposure to heat in addition to the smoking factor. The results showed a clear variation in variables related to erythrocytes between the three age groups, The RBC and Hb level showed a relatively low level in the second age group (4.8 103 ̸ ml and13.0 mg/dl), respectively.accompanied by a marked increase in the level of platelets in the first age group and the highest average (300 L ̸ 109) compared with the control group. The variables related to the white blood cells showed a significant difference, with a significant increase in the total number of WBC, monocytes and granulocytes. The highest average reached in different groups (10%, 0.1% and 0.62%) respectively. Furthermore, a relatively low percentage of lymphocytes were observed in the three groups and the lowest average was (0.324%) compared with the control group. While results related to the effect of smoking factor with temperature showed significant differences, a relative decrease in the level of RBC was observed in the non-smoking workers group. The results of Hb, PCV and PLT concentrations showed a significant increase in the smoking group, reaching the highest mean (14.4 ml ̸ dl, 45% and 264 L̸ 109), respectively, compared with non- smokers and the control group. The WBC value also showed a relatively high increase in the smokers group (8.5%), accompanied by a significant increase in the percentage of lymphocytes, monocytes and granulocytes and the highest mean was (2.5%, 0.6% and 5%), respectively in non-smokers compared to smokers. The results of the effect of the temperature exposure period at an annual rate were relatively different, The group exposed to heat in bakeries for several years (15-30 year) was affected by its hematological variables higher than the group exposed to heat for less than years (1-15 year). Therefore, the present study suggests a high temperature effect of bakery on some hematological variables in workers.
Key words: heamatological, high temperature, Bakeries