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1.
Heliyon ; 9(5): e15575, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37153391

RESUMO

The presence of heavy metal, chromium (VI), in water environments leads to various diseases in humans, such as cancer, lung tumors, and allergies. This review comparatively examines the use of several adsorbents, such as biosorbents, activated carbon, nanocomposites, and polyaniline (PANI), in terms of the operational parameters (initial chromium (VI) concentration (Co), temperature (T), pH, contact time (t), and adsorbent dosage) to achieve the Langmuir's maximum adsorption capacity (qm) for chromium (VI) adsorption. The study finds that the use of biosorbents (fruit bio-composite, fungus, leave, and oak bark char), activated carbons (HCl-treated dry fruit waste, polyethyleneimine (PEI) and potassium hydroxide (KOH) PEI-KOH alkali-treated rice waste-derived biochar, and KOH/hydrochloric acid (HCl) acid/base-treated commercial), iron-based nanocomposites, magnetic manganese-multiwalled carbon nanotubes nanocomposites, copper-based nanocomposites, graphene oxide functionalized amino acid, and PANI functionalized transition metal are effective in achieving high Langmuir's maximum adsorption capacity (qm) for chromium (VI) adsorption, and that operational parameters such as initial concentration, temperature, pH, contact time, and adsorbent dosage significantly affect the Langmuir's maximum adsorption capacity (qm). Magnetic graphene oxide functionalized amino acid showed the highest experimental and pseudo-second-order kinetic model equilibrium adsorption capacities. The iron oxide functionalized calcium carbonate (IO@CaCO3) nanocomposites showed the highest heterogeneous adsorption capacity. Additionally, Syzygium cumini bark biosorbent is highly effective in treating tannery industrial wastewater with high levels of chromium (VI).

2.
Rev Environ Health ; 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37053495

RESUMO

Exposure of infants to chemicals during their development will have major effects on their health. One of the major exposures of infants to chemicals is through their food. The main structure of infant food is milk, which is high in fat. There is a possibility of accumulation of environmental pollution, including benzo (a) pyrene (BaP). In this systematic review, the amount of BaP in infant milk was surveyed for this purpose. The chosen keywords were: benzo (a) pyrene, BaP, Infant formula, dried milk, powdered milk, and baby food. A total of 46 manuscripts were found in the scientific database. After initial screening and quality assessment, 12 articles were selected for extraction of data. By meta-analysis, the total estimate of BaP in baby food was calculated to be 0.078 ± 0.006 µg/kg. Estimation of daily intake (EDI) and Hazard Quotient (HQ) for noncarcinogenic risk and Margin of exposure (MOE) for carcinogenic risk were also calculated for three age groups 0-6 months, 6-12 months, and 1-3 years. HQ was lower than 1 and MOE was more than 10,000 for three age groups. Therefore, there is no potential carcinogenic and non-carcinogenic risk for infant health.

3.
Environ Sci Pollut Res Int ; 29(37): 55437-55456, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35676570

RESUMO

This systematic review aims to identify the sources of exposure to polychlorinated biphenyls (PCBs), portioning, and human health risk assessment in Iran. The literature was searched in the international databases of Web of Science, PubMed, Scopus, Google Scholar, and the national databases of SID and MagIran up to November 14, 2020. Among all 153 articles, 21 eligible papers were identified. Among them, only one article was related to drinking water, the rest was related to food and soil, and no article was found on ambient air. The corrected portion of each exposure source was determined to be 90% for food, 9% for water, and 1% for air. The total hazard quotient (HQ) was determined to be within an unsafe range, and the total excess lifetime cancer risk (ELCR) was determined to be at a high risk of oral carcinogenesis. It is suggested that a comprehensive study be conducted in a specific period for all sources of exposure in all counties of Iran. Moreover, it is recommended that the policymakers set national standards for this pollutant in near future in some sources of exposure (e.g., drinking water) which have no standards in Iran.


Assuntos
Água Potável , Bifenilos Policlorados , Monitoramento Ambiental , Humanos , Irã (Geográfico) , Bifenilos Policlorados/análise , Medição de Risco , Solo
4.
Food Chem X ; 14: 100283, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35296041

RESUMO

Considering the importance of onions consumption in the household diet, controlling of heavy elements' concentration in foodstuffs is important to ensure the safety of an individual's health. This study aimed to evaluate the risk of heavy metals through onion consumption on human health. In this cross-sectional experimental study, 22 onion samples with varieties red, yellow, and white in the two autumn and winter seasons in 2020 were randomly collected from the different provinces of Kurdistan, Hamedan, and Kermanshah. The concentrations of heavy metals were evaluated with an atomic absorption spectrometer. The risks of human health were evaluated by the hazard quotient (HQ) and the obtained results were analyzed with one-way ANOVA and one sample t-test. The obtained findings demonstrated that all collected samples contained heavy metals. For example, the cadmium (Cd) concentration in onion samples in the province of West Azerbaijan, Kurdistan, Hormozgan, Isfahan, and Zanjan was 526.49, 274.49, 69.77, 67.39, 65.69 µg kg-1, respectively. While the standard specified in Iran for the concentration of Cd in onions is 50 µg kg-1. However, the rate of lead (Pb) contamination in samples collected from Isfahan, Hormozgan, Zanjan Khuzestan, Tehran (Varamin) was 296.50, 266.71, 261.49, 215.64, 106.19 µg kg-1, respectively, which less than maximum allowable limit recommended by WHO-FAO (300 µg kg-1). The HQ for non-cancerous diseases for Cd and Pb were 8.6 × 10-2 and 1.6 × 10-1, respectively, and the probability of carcinogenic risk for Pb (8.1 × 10-4) was at the level of acceptable. There is no concern about the non-carcinogenic diseases and carcinogenic risk of consuming heavy metals in onion. Therefore, for optimal management and prevention of further pollution, it is recommended to study the origin and determine the amounts of heavy metals for their potential contamination of foodstuffs from the region's soil, water, and dust.

5.
Environ Sci Pollut Res Int ; 28(35): 48955-48966, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33928508

RESUMO

Bottled water use has become widespread in recent years. Many Iranian cities are located in regions with a hot and semi-hot climate, and the quality of drinking water is low in most of these areas. Nitrate and fluoride are chemical constituents of drinking water with significant health concerns since they can be harmful in concentrations higher than drinking water standards. This study aims to determine nitrate and fluoride concentrations in different bottled water brands in the study region; evaluate the non-carcinogenic health risks posed by nitrate and fluoride exposure via the ingestion of bottled water; and compare the measured nitrate and fluoride concentrations with the amounts reported on the bottle labels. Twenty bottled water brands were sampled, and their nitrate and fluoride amounts were determined using the spectrophotometry method. The results revealed that 100% of nitrate and 70% of fluoride in samples had concentrations greater than the levels reported on bottle labels. Minimum, maximum, and mean concentrations for nitrate were, respectively, 1.1, 28, and 8.37 mg/L, and for fluoride were 0.014, 2.36, and 0.63 mg/L. The hazard quotient (HQ) values due to nitrate intake were > 1 in 10% of the samples (n = 2) for both infants and children, indicating potential adverse non-carcinogenic health effects upon consumption. For fluoride intake, the potential adverse health effects (HQ > 1) for infants, children, teenagers, and adults were respectively high in 30, 20, 10, and 10% of the samples. For nitrate, the 95th centile for infants was 1.547, and for fluoride, it was 2.62, 2.19, 1.15, and 1 for infants, children, teenagers, and adults, respectively.


Assuntos
Água Potável , Adolescente , Adulto , Criança , Água Potável/análise , Fluoretos/análise , Humanos , Lactente , Irã (Geográfico) , Nitratos , Medição de Risco
6.
Environ Sci Pollut Res Int ; 28(11): 13055-13071, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33483929

RESUMO

This study has systematically reviewed all of the research articles about the photocatalytic degradation of pesticides using titanium dioxide (TiO2) nanoparticles (NPs) and ultraviolet (UV) irradiation. Online databases were searched for peer-reviewed research articles and conference proceedings published during 2009-2019, and ultimately 112 eligible articles were included in the review. Fifty-three active ingredients of pesticides and one mixture had been investigated, most of them were organophosphorus (22%), followed by triazine derivatives (11%), chloropyridines (9%), and organochlorines (9%). Sixteen types of TiO2 with an average photodegradation efficiency of 71% were determined. Based on the type of pesticide and experimental conditions such as irradiation time, the complete photodegradation had been observed. The removal of each group of pesticides has been sufficiently discussed in the article. Effect of experimental conditions on photocatalytic activity has been investigated using linear and polynomial regressions. The strategies to reduce the required energy for this process, doping TiO2 with metal and non-metal agents, innovative reactor designs, etc., were also discussed. In conclusion, TiO2 NPs have been successful for degradation of pesticides. Future direction for research incorporates developing and application of heterogeneous doped and immobilized titania having optimized characteristics such as surface area, reactive centers, recombination rate, and phase, and capable to photo-degrade low levels of pesticides residues under solar light in an efficient full-scale size.


Assuntos
Praguicidas , Poluentes Químicos da Água , Catálise , Titânio
7.
Environ Monit Assess ; 192(7): 431, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32537659

RESUMO

The main aim of this study was to evaluate gamma radiation level in the mineral hot springs of Ardabil province in Iran. In addition, the cancer risk of gamma radiation was assessed for swimmers. Natural gamma radiation was measured using Ion Chamber Survey Meter 451B in 22 springs throughout the province. Gamma was measured at 20 cm and 100 cm above the ground level in 15 locations of each spring. Excess lifetime cancer risk was calculated to investigate the risk of exposure to gamma radiation. The highest and lowest annual absorbed dose rate of gamma were found to be 1.17(10-3) and 1.99(10-3) Sv/y at the height of 20 cm above the ground level and 5.26(10-4) and 1.52(10-3) Sv/y at the height of 100 cm above the ground level, respectively. Excess lifetime cancer risk ranged from 4.57(10-4) to 7.76(10-4) at the height of 20 cm and from 2.06(10-4) to 5.94(10-4) at the height of 100 cm which are lower than global average of 1.45(10-3) declared by the United Nations. Although the risk level in this study is lower than the global average, protective and preventive measures should be considered by individuals and authorities in these areas to reduce the effects of gamma radiation on the health of the swimmers.


Assuntos
Fontes Termais , Monitoramento de Radiação , Radiação de Fundo , Raios gama , Humanos , Irã (Geográfico) , Minerais , Doses de Radiação
8.
Iran J Public Health ; 48(5): 902-911, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31523647

RESUMO

BACKGROUND: Contamination of hair dyes to heavy metals can threaten consumer's health. We investigated the concentrations of some important heavy metals in hair dyes and evaluates their non-carcinogenic effects. METHODS: The most commonly used hair dyes were determined through questioners and 32 samples were collected from the market of Tehran in 2014. The concentration of 10 heavy metals (Fe, Ag, Co, Cr, Mn, Ba, Cd, Cu, Pb, and Al) was determined using ICP-MS. Based on the obtained data from distributed questionnaires and Monte Carlo simulation, the exposure to the evaluated heavy metals was estimated. Besides, using hazard quotient (HQ) and chronic hazard (HI), the risk of non-carcinogenic effects of investigated hair dyes consumption was specified. RESULTS: Results indicated the average concentrations of Al, Ba, and Fe as 0.54, 0.86, and 1.19 mg kg-1 and those of Cd, Cu, and Pb as 0.45, 61.32, and 185.34 µg kg-1, respectively. Pb with HQ of 7.46e-4 had the highest risk and Fe with HQ of 3.4e-6 had the lowest level of risk. Among the investigated dyes, the ones made by Iran (HI=2.8e-4) and the dark brown color (HI=1.93e-4) had the highest level of risk among all the studied samples. CONCLUSION: Two indices of HI and HQ showed that heavy metal contents in the investigated samples had not probable non-carcinogenic risks for the consumers of these products.

10.
Ecotoxicol Environ Saf ; 175: 128-137, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30897411

RESUMO

The aim of present study was to evaluate the effects of different pre-cooking and cooking methods on the concentration of toxic (As, Cd and Pb) and essential (Fe, Cu, Co and Zn) metals in widely consumed rice types by Tehran households, Iran. In this regard, a total of 90 samples were obtained from Iranian, Pakistani and Indian rice brands (30 samples from each brand), and were examined in order to determine the concentration of toxic metals including As, Cd, Pb, Fe, Zn, Co and Cu using ICP-OES. Among these rice brands, the most contaminated one was selected in order to evaluate the effects of washing and soaking processes in different time points (1, 5 and 12 h), as well as different cooking methods (Rinsing and Kateh) in reducing the concentration of subjected metals. Nine samples were analyzed for each process, which were 54 samples in total. Our results show that the preparation and cooking methods applied for all rice brands (except for Indian rice) could effectively reduce the non-carcinogenic risk associated with these metals to the acceptable level; however, this is not true about the carcinogenic risk associated with arsenic. Finally, according to our findings it can be concluded that all cooking methods can lead to considerable removal of rice toxic metals (this is partially true about all available rice brands in Iran), however, a large amount of essential metals were also eliminated by these methods. Moreover, after cooking of different rice types in Iran, this food has still carcinogenic risk associated with arsenic.


Assuntos
Arsênio/análise , Carcinógenos/análise , Culinária/métodos , Grão Comestível , Contaminação de Alimentos/prevenção & controle , Oryza , Contaminação de Alimentos/análise , Humanos , Irã (Geográfico) , Metais , Metais Pesados , Medição de Risco
11.
J Environ Health Sci Eng ; 17(2): 619-632, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32030138

RESUMO

Trihalomethanes (THMs) have been proven to be potentially genotoxic and mutagenic for human. The aim of this study was to characterize the THMs spatiotemporal distribution and its carcinogenic risk potential in Ardabil water distribution system. Water samples were collected over consecutive months from twenty-six points in the city of Ardabil from April 2016 to March 2017. The potential carcinogenic risk assessment of THMs was evaluated quantitatively with uncertainty assessment based on Monte-Carlo simulation technique. The results showed that the mean concentrations of bromodichloromethane, Chloroform, dibromochloromethane and Bromoform in water consumed by residents were 101.97 ± 58.51, 85.18 ± 47.79, 51.67 ± 29.57 and 11.89 ± 6.64 µg/L, respectively, during the sampling period. According to the result of this study, the concentrations of THMs were higher in summer in comparison with other seasons. The mean values of lifetime cancer risks for residents through ingestion, inhalation and dermal contact are 2.85×10-4, 6.46×10-7, and 1.26×10-7, respectively. The lifetime cancer risks for residents through ingestion was found to be 285 times more than the minimum or negligible level set by US.EPA (1.0×10-6) and for dermal contact and inhalation lower than the minimum or negligible level set by US.EPA. The results of the present research may contribute to inform the decision makers of drinking water supply system about the role of water quality in the health of consumers.

12.
J Environ Health Sci Eng ; 17(2): 1163-1169, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32030182

RESUMO

Daily intake of elements through the consumption of drinking water, due to its detrimental effects, is accounted for an important concern. Although the health risk assessment of heavy metals in different water sources has extensively carried out in various studies, the effect of age and the concentration of all trace elements in drinking tap water have neglected. Therefore, this study was conducted to evaluate the concentrations of heavy metals, e.g., As, Cd, Cr, Ni, Pb, B, Al, Hg, Mn, Zn, Cu, Fe, Se and Ba in the drinking tap water of Zahedan city and to estimate their non-carcinogenic and carcinogenic effects. Moreover, this is the first research in Iran that has also been dedicated to complete investigation on daily intakes of trace elements in tap water. A total of 155 samples of drinking water were randomly taken from the tap water and were analyzed using ICP-OES device. The estimation of the carcinogenic and non-carcinogenic risks of analyzed elements was carried out based on the guidelines of the U.S EPA. The hazard index (HI) values for children and adult age groups were 9.84E-01 and 4.22E-01, respectively. The cumulative Excess Lifetime Cancer Risk (ELCR) for carcinogenic trace elements was in range of tolerable carcinogenic risk 10-6 to10-4 and for all carcinogenic elements were in the order of Pb > Cd > Cr. It also detected that the total carcinogenic risks of the Cd, As and Cr in water samples through the ingestion route are at the levels of "low risk" and "low-medium risk".

13.
J Glob Health ; 8(2): 020702, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30356511

RESUMO

BACKGROUND: In 2015, it was estimated that the burden of disease in Iran comprised of 19 million disability-adjusted life years (DALYs), 74% of which were due to non-communicable diseases (NCDs). The observed leading causes of death were cardiovascular diseases (41.9%), neoplasms (14.9%), and road traffic injuries (7.4%). Even so, the health research investment in Iran continues to remain limited. This study aims to identify national health research priorities in Iran for the next five years to assist the efficient use of resources towards achieving the long-term health targets. METHODS: Adapting the Child Health and Nutrition Research Initiative (CHNRI) method, this study engaged 48 prominent Iranian academic leaders in the areas related to Iran's long-term health targets, a group of research funders and policy makers, and 68 stakeholders from the wider society. 128 proposed research questions were scored independently using a set of five criteria: feasibility, impact on health, impact on economy, capacity building, and equity. FINDINGS: The top-10 priorities were focused on the research questions relating to: health insurance system reforms to improve equity; integration of NCDs prevention strategy into primary health care; cost-effective population-level interventions for NCDs and road traffic injury prevention; tailoring medical qualifications; epidemiological assessment of NCDs by geographic areas; equality in the distribution of health resources and services; current and future common health problems in Iran's elderly and strategies to reduce their economic burden; the status of antibiotic resistance in Iran and strategies to promote rational use of antibiotics; the health impacts of water crisis; and research to replace the physician-centered health system with a team-based one. CONCLUSIONS: These findings highlight consensus amongst various prominent Iranian researchers and stakeholders over the research priorities that require investment to generate information and knowledge relevant to the national health targets and policies. The exercise should assist in addressing the knowledge gaps to support both the National General Health Policies by 2025 and the health targets of the United Nations' Sustainable Development Goals by 2030.


Assuntos
Pesquisa/organização & administração , Causas de Morte/tendências , Pessoas com Deficiência/estatística & dados numéricos , Objetivos , Humanos , Irã (Geográfico)/epidemiologia , Doenças não Transmissíveis/epidemiologia , Doenças não Transmissíveis/prevenção & controle , Anos de Vida Ajustados por Qualidade de Vida
14.
Data Brief ; 20: 1764-1768, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30294621

RESUMO

Natural gas is a kind of fuel that is used in various heating systems for combustion processes. Combustion of natural gas produce such air pollutants as CO2, NOx, SOx, PM, CO, and HC. During cold days, total gas consumption in Iran goes up. Thus, in these days it is likely to make some changes in gas properties that can affect the emissions from gas heaters. Portable flue gas analyzer (LANCOM III) was used for, SO2, NOX, and CXHY measurement from December 2012 to April 2013. Data show that emissions of pollutants from the gas heater were different during the cold seasons. On colder days, total gas consumption in the country increased, SO2 emerged in heater stack, and the concentration of hydrocarbons (CXHY) significantly increased as well. This emergence could be attributed to the changes in gas properties in the colder days. In these days, the transient flow and high changes of speed and pressure in the gas pipes could lead to release of some deposited sulfur in gas flow. Therefore, sulfur dioxide will be generated in the combustion process.

15.
Data Brief ; 20: 825-830, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30211282

RESUMO

The general goal of this data was to determine the concentration of fluoride and assess its risk in waters bottled in Iran. Seventy-one samples of different brands of bottled water were collected. Then, the fluoride concentration was measured through standard method for water and wastewater experiments. The non-carcinogenicity risk of fluoride for different groups of infants, children, teenagers, and adults was calculated by proper formula. The data presented here indicated that the mean concentration of fluoride in bottled waters was 0.272 mg/L, which is lower than the minimum world health organization (WHO) guideline. Further, the mean hazard quotient (HQ) values for fluoride across the groups of infants, children, teenagers, and adults with respective values of 0.0363, 0.2568, 0.1813, and 0.1452 were observed in 0, 1, 1, and 0 cases of HQ>1. Generally, in most of the tested brands, HQ value was less than 1, and this value was above 1 in only one brand of bottled water.

16.
Data Brief ; 17: 731-738, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29876430

RESUMO

This dataset deals with the modification of granular activated carbon (GAC) with FeCl3 under basic conditions (pH ≈ 12) for removal of aluminium (Al) from aqueous solution. The structural properties and operational parameters including Al ion concentration (2.15 and 10.3 mg/L), pH solution (2-10), adsorbent dosage (0.1-5 g/L), and contact time (0-10 h) was investigated for raw and modified GAC. This dataset provides information about Al removal by GAC and modified GAC at conditions including: pH = 8, contact time = 6 h, initial Al concentration = 2.15 mg/L. The characterization data of the adsorbents was analysed by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and Brunauer, Emmett and Teller (BET) test. The data showed that Freundlich isotherm with and Pseudo second order kinetic model were the best models for describing the Al adsorption reactions. The acquired data indicated that the maximum adsorption capacity of GAC and modified GAC to uptake Al (C0 = 10.3 mg/L) was 3 and 4.37 mg/g respectively.

17.
Ecotoxicol Environ Saf ; 155: 133-143, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29510308

RESUMO

This study reports a spatiotemporal characterization of toluene, benzene, ethylbenzene, and xylenes concentrations (BTEX) in an urban hot spot in Iran, specifically at an bus terminal region in Shiraz. Sampling was carried out according to NIOSH Compendium Method 1501. The inverse distance weighting (IDW) method was applied for spatial mapping. The Monte Carlo simulation technique was applied to evaluate carcinogenic and non-carcinogenic risk owing to BTEX exposure. The highest average BTEX concentrations were observed for benzene in the morning (at 7:00-9:00 A.M. local time) (26.15 ±â€¯17.65 µg/m3) and evening (at 6:00-8:00 P.M. local time) (34.44 ±â€¯15.63 µg/m3). The benzene to toluene ratios in the morning and evening were 2.02 and 3.07, respectively. The main sources of BTEX were gas stations and a municipal solid waste transfer station. The inhalation lifetime cancer risk (LTCR) for benzene in the morning and evening were 1.96 × 10-4 and 2.49 × 10-4, respectively, which exceeds the recommended value by US EPA and WHO. The hazard quotient (HQ) of all these pollutants was less than 1. The results of this work have implications for public health near 'hot spots' such as IKBT where large populations are exposed to carcinogenic emissions.


Assuntos
Poluentes Atmosféricos , Derivados de Benzeno , Benzeno , Neoplasias/induzido quimicamente , Tolueno , Xilenos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Benzeno/análise , Benzeno/toxicidade , Derivados de Benzeno/análise , Derivados de Benzeno/toxicidade , Cidades , Monitoramento Ambiental/métodos , Humanos , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Irã (Geográfico) , Medição de Risco , Tolueno/análise , Tolueno/toxicidade , Xilenos/análise , Xilenos/toxicidade
18.
Artigo em Inglês | MEDLINE | ID: mdl-29051819

RESUMO

BACKGROUND: Polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDFs) are highly toxic persistent organic pollutants (POPs), which can cause various health outcomes, such as cancer. As a part of the National and Sub-national Burden of Disease Study (NASBOD), we aimed to estimate dioxins and furans national emissions, identify their main sources, estimate daily intake doses, and assess their trend from 1990-2010 in Iran. METHODS: The Toolkit for Identification and Quantification of Releases of Dioxins, Furans and Other Unintentional POPs, which is developed by the United Nations Environment Programme (UNEP 2013), was used to estimate the emissions of PCDD/PCDFs from several sources into the air, water, land, residue, and other products. The daily intake doses were estimated using a linear regression of estimated emissions by UNEP Toolkit and average intake doses in other countries. Finally, the trend of PCDD/PCDFs emissions and daily intake doses were explored from 1990-2010. RESULTS: The total emissions were estimated as 960 g Toxic Equivalents (g TEQ) for 1990 and 1957 g TEQ for 2010 (18.2 and 26.8 g TEQ per million capita, respectively). The estimations suggest that albeit contribution of open burning to PCDD/PCDFs emissions has been declining from 1990 to 2010, it remained the major source of emissions in Iran contributing to about 45.8% out of total emissions in 1990 to 35.7% in 2010. We further found that PCDD/PCDFs are mostly emitted into the ambient air, followed by residue, land, products, and water. The daily intake doses were estimated to be 3.1 and 5.4 pg TEQ/kg bw/day for 1990 and 2010, respectively. We estimated an increasing trend for PCDD/PCDFs emissions and intake doses in Iran from 1990-2010. CONCLUSIONS: The high levels of emissions, intake doses, and their increasing trend in Iran may pose a substantial health risk to the Iranian population. Further studies with more rigorous methods are recommended but this should not circumvent taking appropriate policy actions against these pollutants. Currently, Iran has no standard for dioxins and furans. Adaptation of the World Health Organization recommended guidelines might be an appropriate starting point to control dioxins and furans emissions.

20.
Artigo em Inglês | MEDLINE | ID: mdl-28261488

RESUMO

BACKGROUND: In Iran, re-refinery industry has been developed many years ago based on the acid-clay treatment. Acidic sludge with high concentration of total petroleum hydrocarbon (TPH) is the final products of some facilities. In this study removal of TPH by aerated in-vessel composting was investigated. METHODS: In order to microorganisms seeding and nutrient providing, urban immature compost was added as an amendment to acidic sludge. The ratios of acidic sludge (AS) to compost were, 1:0 (as control), 1:5, 1:8, 1:10, 1:15, 1:20, 1:30, 1:40, 1:50, 1:75 and 1:100 (as dry basis) at a C: N: P ratio of 100:5:1 and 45-65% moisture content for 70 days. RESULTS: The removal efficiency in all reactors was more than 48%. The highest and lowest TPH removal was observed in 1:5 (71.56%) and 1:100 (48.53%) mixing ratios, respectively. The results of the control reactors showed that biological treatment was the main mechanism for TPH removal. Experimental data was fitted second order kinetic model (R2 > 0.8006). Degradation of TPH in 1:5 mixing ratio (k2 = 0.0038 gmg -1d-1; half-life = 3.08d) was nearly three times faster than 1:100 mixing ratio (k2 = 0.0238; half-life = 8.96d). The results of the control reactors showed that biological treatment was the main mechanism for TPH removal. CONCLUSION: The results of this study revealed in-vessel composting with immature urban compost as the amendment maybe recommended as an effective method for TPH remediation.

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