Polycyclic aromatic hydrocarbons (PAHs) formation during the fast pyrolysis of hazardous health-care waste.

Health-care waste management is a challenge for the health sector. Currently, pyrolysis technologies are being used to treat medical waste that can convert it to a hydrocarbon fuel. In the present study, hazardous health-care waste was pyrolyzed using a continuous tubular fast pyrolysis reactor. Mass balance analysis and formation of the 16 polycyclic aromatic hydrocarbons (PAHs), characterized by USEPA as priority pollutants, and was studied during the pyrolysis process in a wide range of operation conditions, i.e., reaction temperature (300-700 °C), residence time (100-190 s) and waste particle size (1-3 cm). Response surface methodology (RSM) and central composite design (CCD) were applied to optimize the operating variables. Cracking and decomposition of feedstock occurred almost optimally in 700 °C resulting in the generation of 73.4% liquid and 24.1% char. The PAHs were characterized in significant concentrations in pyrolytic oil (121-29440 mg/lit) and char (223-1610 mg/kg) products. The formation of total USEPA listed PAH components varied by the operating ranges of temperature, residence time and waste size. In the pyrolytic oil phase, the formation of total PAHs was drastically increased by increasing the waste particle size. It is also found that increasing the temperature and having longer residence times have a high influence on the total 16 USEPA PAHs formation rate in the char phase. It is concluded that fast pyrolysis of hazardous health-care waste, as thermal treatment method, would influence the formation and destruction of PAHs and their fraction to a different extent depending on the role of operating variables.

National and sub-national environmental burden of disease in Iran from 1990 to 2013-study profile.

BACKGROUND: Development of national evidence-based public health strategies requires a deep understanding of the role of major risk factors (RFs) and the burden of disease (BOD). In this article, we explain the framework for studying the national and sub-national Environmental Burden of Disease (EBD) in Iran as a part of the National and Sub-national Burden of Disease (NASBOD) study. METHODS: The distribution of exposures to environmental RFs and their attributable effect size over 1990-2013 will be estimated through comprehensive reviews of either published or unpublished sources. Statistical modeling will be used to impute missing data in the distribution of RFs exposures for each district-year. National and sub-national BOD attributable to these RFs will be estimated in the following metrics: Prevalence, death, years of life lost due to premature death (YLL), years of life lost due to disability (YLD), and disability-adjusted life years lost (DALYs). The BOD attributable to the current distribution of exposures will be compared with a counterfactual exposure distribution scenario-here, the theoretical-minimum-risk exposure distribution. Inequalities in the distribution of exposure to RFs will be analyzed and manifested nationwide using geographic information systems. DISCUSSION: The EBD study aims to provide an official report to Iranian Ministry of Health and Medical Education, to publish a series of articles on the exposure trends of the selected environmental RFs, to estimate the BOD attributable to these RFs, and to assess inequalities and its determinants in the distribution of exposure to RFs. Iran's territory is large with diverse population, socioeconomic, and geographic areas. Results of this comparative risk assessment study may pave the way for health policy makers to plan more comprehensive and cost-effective evidence-based strategies.

E-waste management challenges in Iran: presenting some strategies for improvement of current conditions.

E-waste is one of the fastest-growing waste streams in Iran, owing to an increase in consumption of electrical and electronic equipment. Nevertheless, as is the case in some other countries, E-waste management has not received sufficient attention. For the successful implementation of any waste management plan (including an E-waste management plan), the availability of sufficient and accurate information on the quantities and composition of the waste generated and on current management conditions is a fundamental prerequisite. At present, in Iran, there is no available and accurate information that describes the characteristics and generation rate of E-waste or the actual practice of management and handling of the waste. For this initial study, eight electronic products were selected for the determination of their E-waste generation rate in the country, and two cities, Tehran and Tabriz, were selected for assessment of the current condition of E-waste management. The study found that the amount of E-waste generation in the country for the eight selected electronic items alone was 115,286, 112,914 and 115,151 metric tons in 2008, 2009 and 2010, respectively. Of the types of electronic items included in the study, televisions, with an average of 42.42%, and PCs, with an average of 32.66% accounted for the greatest proportions of the total mass of E-waste generated during 2008-2010. Currently, despite the fact that primary legislation for E-waste management (as part of general waste legislation) exists in Iran, this primary legislation has not yet been implemented. In practical terms, there is no definite policy or plan for the allocation of funds to prepare suitable equipment and facilities for the management and recycling of E-waste at the end of the products' useful life. Proposed improvements in current conditions are identified, first by considering other countries' experiences and then suggesting specific practical policies, rules, and regulations that should be established and applied to all levels of E-waste management. One of the most attractive E-waste management policies is an extended producer responsibility (EPR) programme in combination with a training programme at different levels of society. An approach consisting of a mandated product take back is proposed for implementing EPR in Iran. Meanwhile, the Health Ministry and the Environmental Protection Agency should strictly supervise E-waste collection, storage, and recycling and/or disposal, and the Trade and Industry Ministries must have more control over the import and production of electronic goods.

Nitrate Determination of Vegetables in Varzeghan City, North-western Iran.

Background Vegetables play an important role in human nutrition. Nitrate content is a signifi-cant quality criterion to determine characteristic of vegetables. About 80% of nitrate intake in human is from vegetables and fruits. High dietary intake of nitrate is seen as an undesirable be-cause of its association with gastric cancer and infantile methemoglobinemia. Varzeghan, North¬western Iran is one of the cities with high Age-standardized incidence rates (ASR) of gastric can¬cer in Iran. Currently, in Varzeghan there is no available and accurate information describing ni¬trate concentration as one of the important risk factors of vegetables for human consumption. Methods In this cross sectional study totally 11 types of vegetables (cabbage, lettuce, spinach, parsley, coriander, dill, leek, fenugreek, tarragon, fumitory and mint) from several different green¬grocery of Varzeghan were collected in spring (April) and autumn (November and December) 2011 and their nitrate contents were analyzed. Results Mean nitrate contents at the above noted fresh vegetables were 161, 781, 83, 707, 441, 501, 1702, 684, 805, 772 and 191 mg NO3-kg-1 respectively. In none of the 11 fresh vegetables nitrate content were not more than established limitations. Conclusion Nitrate concentrations were below of others reported at different countries. The mean concentration of nitrate at all vegetables in autumn was higher than in spring significantly.