05 August 2008

SCIENCE: Study of occupational health impact of atmospheric pollution on exposed workers at an iron and steel complex ...

SCIENCE: Study of occupational health impact of atmospheric pollution on exposed workers at an iron and steel complex by using neutron activation analysis of scalp hair

Article in Journal of Radioanalytical and Nuclear Chemistry, Vol. 259, No. 1 (2004) 153.156 by Z. F. Chai, Q. F. Qian, X. Q. Feng, P. Q. Zhang, N. Q. Liu, W. Y. Feng, M. X. Kuang, H. Y. Wang, Y. Z. Zhang of Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, P.R. China & General Hospital of Capital Steel and Iron Company, Beijing, P.R. China.

Abstract

The occupational health impact of atmospheric pollution on exposed workers at one iron and steel complex was studied by instrumental neutron activation analysis of workers’ hair samples and medical examination. The experimental results indicate that there is a positive correlation between the high inhalation amounts of iron and other trace elements by the exposed workers and the symptom of their high blood pressure and hypoglycemia, which implies that the atmospheric environment polluted by iron and steel industry has an adverse health impact on the exposed workers. The measures to relieve and abate the occupational diseases caused by air-borne particulate matter should be taken.

Extracts

More and more attention has been paid to occupational health impact at workplace,1 especially in mining, metal refining and metal working industries.2 Excessive exposure to trace metals released by iron and steel industry has become one of the major environmental pollution problems, especially in developing and economically-emerging countries. However, the related report on the correlation between the chronic or acute exposure of chemical elements and workers’ health effect is scarce. For better understanding the health impact of this industrious activity, a representative iron and steel company in Beijing, China, i.e., Capital Iron and Steel Company (CISC) was selected as a target working area, which was one of the biggest industrious enterprises in China. Its annual steel output is up to 10 million tons. The atmospheric particle matter (APM) released by this company in the eighties constituted about 55% of the total APM in the metropolitan city.3,4 The local government and people are more and more concerned about the atmospheric pollution, especially herein heavy metals and toxic elements, caused by CISC and the health impact on occupational workers at workplace and on population living in its surrounding regions. As a part of the municipal environmental monitoring and health survey and the coordinated research project on ‘Assessment of Levels and Health Effects of Airborne Particulate Matter in Mining, Metal Refining and Metal Working Industries Using Nuclear and Related Analytical Techniques’ organized by the International Atomic Energy Agency, we systematically studied the status of environmental pollution and health impact on furnace workers at workplace caused by CISC. In order to monitor the status of environmental pollution, various biological indicators or biomarkers have been developed.5 In this paper, the human hair was utilized as biomonitoring specimen and analyzed by instrumental neutron activation analysis, by which the evaluation of health impact of environmental pollution caused by iron and steel complex on exposed workers was made.

Results and discussion

Content of trace elements in the hair samples of the exposed workers, staff members and control group

... From the average contents of trace elements in the hair samples of the 3 different groups, it can be seen that the contents of some pollution elements (e.g., Fe, Cr, Co and Mn, etc.) in the hair samples of the exposed workers and staff members at the workplace of CISC are very high compared with those of the control group. The most serious pollution element at CISC is iron. The hair of the exposed workers contains 10 times higher Fe concentrations than of the controls.

... As a basic principle of the biological effects of trace elements, any element is harmful to human health, if its amount of intake is overor ill-dose (e.g., Reference 11). The excessive intake of iron by the workers may play an adverse role of their health.

Health impact of the atmospheric pollution on the exposed workers
To assess the health impact of atmospheric pollution caused by iron and steel smelters at CISC on humans, a medical survey for the young workers and staff members (50 each, 20.35 years old) working there was carried out, along with 35 individuals at the same age range living at a relatively clean area as controls. The statistical treatment indicates that more workers and staff members suffer the symptoms of high blood pressure, hypoglycemia and other chronic diseases than the controls. The percentages of the high blood pressure and hypoglycemia for the workers, staff members and controls are 46, 24 and 11% of total specimen numbers, respectively, which implies that the inhalation of excess Fe and other metallic elements may cause adverse health impact.

Until now, the report on the health impact of atmospheric pollution at workplace is available, but the quantitative evaluation of this effect is very difficult. Based on our results of atmospheric monitoring at CISC, the inhalation amounts of trace elements in 0.4 and 8 µm air particles by the exposed workers can be estimated and listed in Table 4, together with the total amount of the air-borne particles with the size over 0.4 µm. It is evident from Table 4 that the inhaled amount of Fe is very high, up to 144 (0.4 µm), 398 (8 µm) and total 542 µg per day. The same is also for other trace elements, such as As, Pb, Rb, Sb, Se and Zn. As medical observation described, the inhalation of excessive ferrous oxide will cause poisonous reactions of respiratory tract,12 including nasal itching, aqueous nasal discharge, abnormal mucous, pharynx itching and irritation, cough, sputum, dyspnoea, chest tightness and pain, etc. Further, the long-term inhalation of ironbearing air particles results in the chronic diseases, even lung cancer.12 As to the relationship between the high iron uptake and cardiovascular diseases, until now no direct evidence is available. This work provides an experimental observation to show the adverse health impact of the atmospheric environment polluted by iron and steel industry on the exposed workers. Nevertheless, more study on the mechanism of its biological effect, especially at the molecular level, is highly needed.


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