[ epidemiological study of accidents in a construction industry: a case-control study]

Despite science and technology development and their application in various industries, accidents continue to occur in many workplaces. This study was designed and carried out with the aim of epidemiological survey of accident among workers of a tunneling industry. This study was conducted on 144 out of a total of 440 employees of a tunneling project who were at risk of occupational accidents. 48 workers with a history of occupational accident over the past two years were selected as case group and 96 workers of the same project were selected as control group. The data were collected through a designed checklist and analyzed using logistic regression, chi-square and independent t tests. A significant association was observed between accident rate and different age groups [p<0.05]. There was a significant relationship [p=0.016] in the case of sport activities between case and control groups, and significant relationships were observed between two groups regarding education [p=0.057] and smoking [p=0.06], but there was no significant relationships between accident occurrence with marital status, residence in workplace, job related education, job experience, chronic diseases and obesity. The results of this study clarify the necessity of the use of epidemiological data in preventive and control measures in workplaces. Therefore, Developing programs for determination of physical and mental capacity of workers are essential to employ them in jobs commensurate with their abilities, especially in older workers

Molecular imprinted solid phase extraction for determination of atrazine in environmental samples

Solid phase extraction is one of the major applications of molecularly imprinted polymers fields for clean-up of environmental and biological samples namely molecularly imprinted solid-phase extraction. In this study, solid phase extraction using the imprinted polymer has been optimized with the experimental design approach for a triazine herbicide, named atrazine with regard to the critical factors which influence the molecular imprinted solid phase extraction efficiency such as sample pH, concentration, flow-rate, volume, elution solvent, washing solvent and sorbent mass. Optimization methods that involve changing one factor at a time can be laborious. A novel approach for the optimization of imprinted solid-phase extraction using chemometrics is described. The factors were evaluated statistically and also validated with spiked water samples and showed a good reproducibility over six consecutive days as well as six within-day experiments. Also, in order to the evaluate efficiency of the optimized molecularly imprinted solid-phase extraction protocols, enrichment capacity, reusability and cross-reactivity of cartridges have been also evaluated. Finally, selective molecularly imprinted solid-phase extraction of atrazine was successfully demonstrated with a recovery above 90% for spiked drinking water samples. It was concluded that the chemometrics is frequently employed for analytical method optimization and based on the obtained results, it is believed that the central composite design could prove beneficial for aiding the molecularly imprinted polymer and molecularly imprinted solid-phase extraction development