Occupational exposure to formaldehyde, lifetime cancer probability, and hazard quotient in pathology lab employees in Iran: a quantitative risk assessment.

Formaldehyde is a colorless and highly irritating substance that is used as a preservative and chemical fixative in tissue processing in pathological laboratories. Formaldehyde is mutagenic and is classified by the IARC as the definitive carcinogen (A1 group). This cross-sectional descriptive-analytical study was performed to determine the respiratory exposure of 60 employees of pathology labs with formaldehyde and to estimate carcinogenic and non-carcinogenic risk in Iran in 2018-2019. Occupational exposure to formaldehyde was assessed in summer season using the NIOSH 3500 method and a personal sampler with flow of 1 l/min connected to two Glass Midget Impingers containing 20 ml of 1% sodium bisulfate solution. The respiratory symptoms questionnaire provided by the American Thoracic Society was used to assess the health effects of formaldehyde exposure. The carcinogenic and non-carcinogenic risk assessment of inhaled exposure to formaldehyde was also performed using the USA Environmental Protection Agency (OEHHA) method. The mean respiratory exposure of employees to formaldehyde was 0.64 mg/m3 (range: 0.1474 to 1.3757). Occupational exposure in 28.3% (n = 17) of employees was above the OSHA recommended range. Wheezing (24%), burning eyes (25%), and cough (21.7%) were the most prevalent health problems. The mean ± SD of the carcinogenic risk among the employees was 3.45 × 10-4 ± 2.27 × 10-4. The highest mean of carcinogenic risk was found in lab workers (4.44 × 10-4). Given the high level of carcinogenic and non-carcinogenic risk of respiratory exposure to formaldehyde in pathological employees, especially lab worker, the use of management controls, engineering controls, and respiratory protection equipment to reduce exposure levels of all workers to less than the allowed exposure limits seems necessary.

Occupational exposure to styrene and its relation with urine mandelic acid, in plastic injection workers.

Plastic injection industry workers are exposed to toxic gases and vapors, including styrene. This study aimed to measure exposure to styrene and its relation with urine mandelic acid among plastics injection workers of the electrical parts industry. This descriptive and analytical cross-sectional study was carried out in the plastic injection halls of the electronics industry, in winter 2017 and spring 2018. Styrene gas in the workers' respiratory region was sampled by the NIOSH 1501 method and was analyzed by gas chromatography-mass spectrometry (GC/MAS). Mandelic acid concentration was determined by high-performance liquid chromatography (HPLC). Statistical data analysis was performed with STATA11. The mean of age and working experience in the population under study were 32.4 ± 8.1 and 6.4 ± 5 years, respectively. The average exposure to styrene was 83.2 ± 32.4 mg·m-3 and the mean of urine mandelic acid was 1570.1 ± 720.6 mg·g ceratinine-1. There were 24 workers (45.3%) exposed to levels above permissible limits recommended by national and international organizations. There was a positive and significant correlation between exposure to styrene and urine mandelic acid (P = 0.006, r = 0.4). In multivariate regression, occupational exposure to styrene (P = 0.002, ß = 0.5) was the strongest variable, predicting the amount of urine mandelic acid. Increased occupational exposure to styrene increases mandelic acid in the urine, and applying control measures to reduce exposure to styrene vapor is recommended in high exposure situations.

Decline in lung function among cement production workers: a meta-analysis.

BACKGROUND: Several studies with different results have been performed regarding cement dust exposure and its pathogenic outcomes during the previous years. This study aims to combine these results to obtain a reliable estimate of the effect of exposure to cement dust. METHODS: PubMed and other data banks were searched to identify required electronic articles. The search was extended interviewing with relevant experts and research centers. Point and pooled estimates of outcome with 95% confidence intervals were estimated. RESULTS: Participants were 5371 exposed and 2650 unexposed persons. Total mean differences (95% confidence intervals) were estimated as of -0.48 (-0.71 to -0.25) L for forced vital capacity (FVC), -0.7 (-0.92 to -0.47) L for forced expiratory volume in the first second (FEV1), -0.43 (-0.68 to -0.19) L for FEV1/FVC%, -0.73 (-1.15 to -0.30) L/min for PEFR and -0.36 (-0.51 to -0.21) L/s for FEF25-75. CONCLUSION: Our meta-analysis showed that cement dust has significant impact on lung function and reduces the indicators of FVC, FEV1, FEV1/FVC, PEFR and FEF25-75.