Assessment of Respiratory and Renal Functions Among Gas Metal Arc Welders and Their Relations with Chromium Exposure

Background: Welding is the most common way of permanently joining metal parts. Welding, soldering, and brazing workers are often exposed to a number of hazards, including the intense light created by the arc, poisonous fumes, and very hot materials. Objective: The aim of this study was to investigate some of the health hazards among gas metal arc welders including renal and pulmonary function tests and to monitor the level of chromium in blood and urine, to study its relation with the renal condition. In addition, our aim was to evaluate ß2 microglobulin in urine as a predictive marker for early renal affection. Patients and methodology: This study was conducted on 18 workers in metal arc welding shops in El Maniel, and El Maadi, Cairo, Egypt. They were adult men aged between 18-42 years, working 12 hours/day with one day off per week. 20 males matched for age, sex, socio-economic status, smoking habits served as a control group. All workers were interviewed using a special questionnaire including occupational history. Ventilatory function tests were done measuring FVC, SVC, FEV1%, FEV1/FVC, MEF 25-75% and PEF. Detection of urinary ß2 microglobulin level, chromium levels in blood and urine, blood urea, serum creatinine and fasting serum sugar levels. Results: Showed statistically significant difference (P<0.05) between the exposed and the control groups as regards spirometric evaluation of FEV1/FVC, PEF%, FVC%, SVC% and MEF 25-75% due to bronchospasm from chemical irritation of the lungs which was related to chromium exposure and its level in blood. It also revealed statistically significant correlation (P<0.05) between the level of blood chromium and renal insult represented by the affection of urinary ß2 microglobulin, urea, and creatinine among the exposed workers indicating renal tubular damage. The results showed no statistically significant correlation (P>0.05) between the duration of exposure to chromium in welders and all investigations done, because chromium is rapidly cleared from the blood, and measurements are related only to the recent exposure. There is a statistically significant correlation (P<0.05) between the levels of chromium in blood, and each of the following: spirometric measures, level of urinary chromium, urinary ß2 microglobulin, serum urea, and creatinine. Conclusion and recommendations: the primary target organ for subchronic and chronic chromium toxicity is the respiratory system, with high levels of blood and urine chromium there was a great insult on the pulmonary functions. Predominant renal injury among welders is tubular, and this injury is correlated Afify, M.; Helal, S.F.; Arafaa, A.M. (2007) Assessment of Respiratory and Renal Functions Among Gas Metal Arc Welders and Their Relations with Chromium Exposure. In Defence against the Effects of Chemical Hazards: Toxicology, Diagnosis and Medical Countermeasures (pp. 22-1 – 22-12). Meeting Proceedings RTO-MP-HFM-149, Paper 22. Neuilly-sur-Seine, France: RTO. Available from: http://www.rto.nato.int. Assessment of Respiratory and Renal Functions Among Gas Metal Arc Welders and Their Relations with Chromium Exposure 22 2 RTO-MP-HFM-149 with the blood chromium level, urinary ß2-microglobulin level could be used as early marker for renal affection. We recommend environmental monitoring in different areas in the welding shops to ensure that permissible levels of different hazardous agents are not exceeded. Pre-employment and periodic medical examinations must be performed to exclude those susceptible to lung and renal diseases. Personal protective clothes e.g. gloves and respiratory protective equipment should be used in welders. Health education programs of workers about hazards of contact with harmful agents and proper measures for protection are essential. Effective local exhaust ventilation to remove hazardous gases and vapors is essential.