Early detection of lung cancer potential among Egyptian wood workers.

Wood dust is known to be a human carcinogen, with a considerable risk of lung cancer. The increased cancer risk is likely induced through its genotoxic effects resulting from oxidative DNA damage. This study aimed at assessing the genotoxicity of wood dust and demonstrating the role of sputum PCR as a screening tool for early prediction of lung cancer among wood workers. The study was carried out in the carpentry section of a modernized factory involved with the manufacture of wooden furniture in Greater Cairo, Egypt. Environmental assessment of respirable wood dust concentrations was done. Frequency of chromosomal aberrations (CA%) and sister chromatid exchanges (SCE%) in peripheral blood lymphocytes (PBL) was assessed and comet assays were performed in samples from among the study population (n = 86). Levels of superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymes were measured. The polymerase chain reaction (PCR) was used to study hypermethylation of p16 and ̸or O6-methylguanine-DNA methyltransferase (MGMT) gene promoters in sputum DNA. The concentrations of respirable wood dust exceeded the Egyptian and international permissible limits with highest levels generated by sawing operations. Laboratory investigations revealed statistically significantly higher frequencies of CA and SCE as well as increased comet tail length associated with significant decrement in the levels of SOD and GPx among exposed group. A statistically significant elevation in the extent of hypermethylation was detected for the p16 and MGMT gene promoters in the sputum DNA of studied wood workers. The study results support the conclusion that prolonged unprotected occupational exposure to wood dust is associated with possible genotoxicity and oxidative stress that might raise the risk for carcinogenesis including lung cancer.

Health hazards among workers in plastic industry.

Styrene is a basic building block for manufacturing thousands of products throughout the world. The present study aimed to (1) detect the presence of styrene and/or its metabolites in the workers in one of the Egyptian plastic factories; (2) demonstrate some common health effects of styrene exposure among the same group by some laboratory investigations and compare them with the unexposed healthy individuals; and (3) correlate the duration of styrene exposure and its level in the blood with the severity of the demonstrated health effects. This study was conducted in one of Egyptian plastic factories. The exposed group was 40 male workers, ranging in age from 18 to 33 years (23.20 ± 4.09), working 12 h/day with 1 day off, and working without any protective equipment. A control group of 50 unexposed healthy males matched with the exposed group for age (21-35 yrs (23.40 ± 4.05)), sex, socioeconomic status, and smoking habit is selected. Written individual consent is obtained from all participants followed by (a) a full medical and occupational history and full clinical examination; (b) ventilatory function tests: forced vital capacity (FVC), slow vital capacity, forced expiratory volume in the 1st second (FEV1)%, FEV1/FVC%, peak expiratory flow, and mid-expiratory flow 25-75%; (c) analyses of ß2 microglobulin; blood styrene level; and urinary mandelic acid; and (d) cytogenetic study. The study results showed a statistically significant difference between the exposed and the control groups as regard the blood styrene level, urinary mandelic acid level, ß2 microgloblin in urine, and chromosomal study. The study also showed a statistically significant correlation between the duration of styrene exposure and ventilatory function parameters, also between the duration of styrene exposure and some detectable chromosomal aberrations. Our study recommends the implementation of preemployment and periodic medical examinations and health education programs using personal protective equipments and following the recommended allowable concentrations of styrene exposure.