Heavy metal contamination in street dusts with various land uses in Zahedan, Iran.

A total of 78 street dust samples (75 within city and 3 from suburban) were collected from different areas with various land use within the city of Zahedan in November 2013 at the end of a long dry period. After digestion, the concentrations of Cd, Cr, Cu, Ni, Pb, and Zn were measured by using ICP-OES. The degree of pollution by heavy metals was assessed with respect to the background concentration by calculation and comparison of the pollution index, integrated pollution index (IPI) and enrichment factor (EF). The mean IPI values (aggregate of six heavy metals) in commercial, high traffic, industrial, urban park, and residential were 3.65, 2.76, 1.68, 1.53 and 1.25, respectively. The results of EF analysis showed almost all sampled urban land use types to be enriched in heavy metals compared with sampled background levels, suggesting heavy metals contamination of street dust in the urban center is from anthropogenic sources.

Dental solid waste characterization and management in Iran: a case study of Sistan and Baluchestan Province.

The management of dental solid waste continues to be a major challenge, particularly in most healthcare facilities of the developing world. In Iran, few studies on management of dental solid waste and its composition are available. An effort has been made through this study to evaluate the hazardous and infectious status of dental solid waste, keeping in mind its possible role in cross-infection chain. For this study, 123 private dental centres and 36 public dental centres were selected and the composition and generation rate of dental solid waste produced were measured. Dental solid waste was classified to four main categories: (i) domestic-type; (ii) potentially infectious; (iii) chemical and pharmaceutical; and (iv) toxic, which constituted 11.7, 80.3, 6.3, and 1.7%, respectively, of the total. Also, the results indicated that the dental solid waste per patient per day generation rate for total, domestic-type, potentially infectious, chemical and pharmaceutical, and toxic wastes were 169.9, 8.6, 153.3, 11.2, and 3.3 g/patient/d, respectively. Furthermore, the per day generation rates for total, domestic-type, potentially infectious, chemical and pharmaceutical, and toxic wastes were 194.5, 22.6, 156.1, 12.3, and 3.4 kg/d, respectively. According to findings of this study, for best management of dental waste it is suggested that source reduction, separation, reuse, and recycling programmes be implemented and each section of dental waste be collected and disposed of separately and in accordance with related criteria.