Investigation on the characteristics and management of dental waste in Urmia, Iran

The objective of this study was to identify the components, composition, generation rate and management of dental waste in Urmia, Iran. Fifteen dental centers including eight general dental offices, five specialist dental offices and two dental clinics were selected and two samples were taken from each office. Then, the wastes were manually separated in 31 components and weighted. The results showed that total dental waste generation in all general dental offices, specialist dental offices and dental clinics were 58.94, 17.92 and 10.22 kg/day, respectively. Domestic, potentially infectious, toxic and chemical and pharmaceutical waste also constituted 35.46, 34.24, 11.83 and 5.56 of total waste, respectively. Only 11 components including blood-contaminated paper towel, saliva-contaminated paper towel, saliva-contaminated cotton, extracted teeth, blood-contaminated gauze, inseparable components, nylon glove, tongue blade, latex glove, saliva ejector and blood-contaminated cotton constituted more than 80 of total infectious waste generation. There was no management program (waste minimization, separation, reuse and recycling) in the dental offices. Source reduction, separation, reuse and recycling activities should be conducted to decrease the hazards of dental wastes. It is also suggested that each fraction of dental waste should be separately collected and disposed in the accordance with its related criteria

MONTMORILLONITE AS ADSORBENT FOR THE REMOVAL OF METHYL RED FROM AQUEOUS SOLUTION

In this study, an organo-clay, montmorillonite (Mt), was used for the removal of methyl red (MR) from aqueous solution. The effect of different parameters on the sorption, such as contact time, pH, adsorbent dosage, initial MR concentration and ionic strength was investigated in batch system. The sorbent was specified by Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD). The optimum uptake capacity of the sorbent (30.84 mg/g) was achieved within 30 min. The solution pH had a significant effect on the sorption capacity of MR by Mt. The experimental data of the sorption was well fitted by pseudo-second-order kinetic and Freundlich isotherm models. The results showed that the Mt can be applied as an effective and cheap sorbent for the removal of MR from aqueous solutions