Occupational Exposure to Nickel in the Ceramic Workers: Biological Monitoring and Respiratory Outcomes

Background: Nickel (Ni) compounds such as nickel oxide are used as pigments in ceramic industries. The toxicity of nickel can occur in the glaze preparation processes. This study aimed to ascertain whether exposure to Ni dust is associated with pulmonary response. Methods: This cross-sectional study was performed on 49 ceramic workers (exposed group) occupationally exposed to nickel dust, as well as 55 unexposed employees (referent group). Information about smoking habits, overtime work, length of employment, skin dermatitis, job title, use of respiratory protection equipment, ventilation system, age, and BMI index were collected through questionnaires. The parameters of pulmonary function were measured. Urine samples were taken from 49 workers at both pre- and post-shift (98 samples). The referent group was examined only once (55 samples). To determine the nickel, the samples were pre-concentrated by Solid Phase Extraction (SPE) and analyzed using  inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Results: Urinary Ni value in the exposed workers was significantly higher than that in the referent group. All pulmonary function parameters in the exposed group were significantly lower than those of the referent group (P<0.001). Those using respiratory protection equipment also exhibited a significantly lower urinary Ni concentration than those not using respiratory protection equipment. Conclusion: These findings indicate that exposure to Ni in the ceramic industry is higher than the recommended biological exposure index and is associated with a significant decrement in the pulmonary function parameters