Publications by authors named "Reza Ali Fallahzadeh"

9 Publications

  • Page 1 of 1

Probabilistic health risk assessment of occupational exposure to isoflurane and sevoflurane in the operating room.

Ecotoxicol Environ Saf 2021 Jan 16;207:111270. Epub 2020 Sep 16.

Genetic and Environmental Adventures Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

Risk assessment is an important tool in predicting the possible risk to health. It heightens awareness by estimating the probability of adverse health effects in humans who are exposed to chemicals in the course of their work. Therefore, the present work aims to determine the occupational exposure of operating room staff to the volatile anesthetic gases, isoflurane and sevoflurane, and estimates non-cancer risk using the United States Environmental Protection Agency method. Air samples from the breathing zone of staff members were collected using the Occupational Safety and Health Administration Method 103 and analyzed using gas chromatography-mass spectroscopy. The results indicate that the measured concentrations of isoflurane and sevoflurane are below the National Institute of Occupational Safety and Health standard (2 ppm) for technicians and nurses, but not for anesthesiologists and surgeons. Moreover, the estimated non-cancer risk due to isoflurane is above the acceptable value for anesthesiologists (but acceptable for other occupational categories). A sensitivity analysis indicates that exposure time has the most effect on calculated risk (53.4%). Occupational exposure to anesthetic gases may endanger the health of operating room personnel. Therefore, control measures, such as daily testing of anesthetic devices, ensuring the effectiveness of ventilation systems, advanced scavenging methods, and regular training of staff are highly recommended.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ecoenv.2020.111270DOI Listing
January 2021

Designing and modeling of a novel electrolysis reactor using porous cathode to produce HO as an oxidant.

MethodsX 2019 1;6:1305-1312. Epub 2019 Jun 1.

Department of Pharmaceutics, Faculty of Pharmacy, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

The entry of toxic organic pollutants and resistant to biodegradation has increased the concern about human health. The use of advanced oxidation (AO) processes to degrade these pollutants has been developing. One of the AO processes is based on the use of hydrogen peroxide in removing resistant organic pollutants. This study aimed to develop a new reactor capable of producing HO in the solution. Therefore, a porous electrode made of stainless steel with the capability of air injection in the electrode center was used. The 30 cm rod graphite electrodes were also used as an anode electrode in a 4000 ml reactor. The effects of variables, including current density (30-40 mA/cm), time (10-30 min), and electrolyte concentration (12-17 mM/L) on the amount of HO production were evaluated by design under response surface methodology using software. The results of this study showed that HO can be produced at the electrode surface of porous cathode under optimal conditions of 36 mA/cm current density, 16 mM/l electrolyte concentration, in 23 min, and in the amount of 34 ppm. Using a porous cathode electrode causes the maximum contact among the solution, water, and air, and increases the production of HO. The release of resistant organic compounds to the waste water is a serious problem to the environment. By the application of the (EO)reactor with the ability to produce HO, this issue is resolved. Furthermore, this technique is applied for non-selective degradation of the toxic organic compounds. •The electro-oxidation process is a useful method for destruction of persistent organic matter from wastewater.•Due to use of porous cathode in this method, contact between the electrode and the sewage is at its maximum level which increases the efficiency and speed of sewage treatment.•This method can produce HO as a high potential oxidant that can reduce persistent organic properties of sewage and make the wastewater suitable for biological treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mex.2019.05.036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6558086PMC
June 2019

Probabilistic risk assessment of occupational exposure to volatile organic compounds in the rendering plant of a poultry slaughterhouse.

Ecotoxicol Environ Saf 2019 Jul 27;176:132-136. Epub 2019 Mar 27.

Department of Ergonomics, School of Health, Hamedan University of Medical Sciences, Hamedan, Iran.

In this study, occupational exposure to volatile organic compounds (VOCs) in the rendering plant of poultry slaughterhouse was determined and subsequently, carcinogen and non-carcinogenic risks were assessed using the US Environmental Protection Agency (USEPA). National Institute for Occupational Safety and Health (NIOSH) methods of 1501 and 1600 were used to measure VOCs in the breathing zone of the workers. Samples were analyzed by GC/MS. Carcinogenic and non-carcinogenic risks and sensitivity analysis were carried out using Monte Carlo simulations technique. The concentration of benzene and CS was higher than the occupational exposure limits (OEL). The hazard quotient (HQ) values for all measured compounds was more than 1, which indicating the high potential for non-carcinogenic risks. Furthermore, the calculated Lifetime Cancer Risks (LCR) for carcinogenic compounds revealed that cancer risk due to benzene is higher than the maximum acceptable level provided by USEPA (10). Based on the sensitivity analysis, the concentration and exposure frequency are the most important variable influencing both carcinogen and non-carcinogenic risks. Therefore, the concentration levels of the VOCs and exposure frequency should be controlled using engineering control measures.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ecoenv.2019.03.079DOI Listing
July 2019

An overview report on the application of heteropoly acids on supporting materials in the photocatalytic degradation of organic pollutants from aqueous solutions.

PeerJ 2018 12;6:e5501. Epub 2018 Sep 12.

Department of Environmental Health Engineering, School of Public Health, Social Development & Health Promotion Research Center, Gonabad University of Medical Sciences, Gonabad, Iran.

Organic pollutants contaminate water resources and the environment when discharged into water streams. Also, the presence of these materials in incompletely treated or untreated wastewater leads to serious environmental hazards. The hydroxyl radicals and holes are regarded as the most oxidant species in the degradation of organic pollutants using the studied composites. The results of this review show that heteropoly acids on supporting materials could be considered as appropriate photocatalysts in the removal of organic pollutant from aqueous solutions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7717/peerj.5501DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6139020PMC
September 2018

Probabilistic risk assessment of exposure to fluoride in most consumed brands of tea in the Middle East.

Food Chem Toxicol 2018 May 19;115:267-272. Epub 2018 Mar 19.

Department of Environmental Health Engineering, Gonabad University of Medical Sciences, Gonabad, Iran. Electronic address:

The aim of this study was to evaluate the fluoride concentration in seven most consumed brands of tea in the Middle East which was imported to Iran through Zabol County. In the present study, the health risk of exposure to fluoride was estimated using a probabilistic approach. Monte Carlo simulation and sensitivity analysis were applied to quantify uncertainties in risk estimation. The highest mean and 95th percentile of chronic daily intake (CDI) was observed for children group. Iranian tea and Kenya tea had maximum CDI and target hazard quotient (THQ) values among studied brands of tea which followed by Green tea, Taksetare tea, Ceylan tea, Red tea, and White tea. These result indicated that there were significant risks of exposure to fluoride in most of studied brands of tea for children (THQ>1). Sensitivity analysis showed that fluoride concentration and daily intake were the most influential variables in three exposed populations. In conclusion, the fluoride concentration in some studied brands of tea is high and it put children at risk risks of exposure to fluoride.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fct.2018.03.023DOI Listing
May 2018

Spatial distribution variation and probabilistic risk assessment of exposure to chromium in ground water supplies; a case study in the east of Iran.

Food Chem Toxicol 2018 May 16;115:260-266. Epub 2018 Mar 16.

Cellular and Molecular Research Center, Department of Environmental Health, School of Public Health, Sabzevar University of Medical Sciences, Sabzevar, Iran. Electronic address:

A high concentration of chromium (VI) in groundwater can threaten the health of consumers. In this study, the concentration of chromium (VI) in 18 drinking water wells in Birjand, Iran, s was investigated over a period of two yearsNon-carcinogenic risk assessment, sensitivity, and uncertainty analysis as well as the most important variables in determining the non-carcinogenic risk for three age groups including children, teens, and adults, were performed using the Monte Carlo simulations technique. The northern and southern regions of the study area had the highest and lowest chromium concentrations, respectively. The chromium concentrations in 16.66% of the samples in an area of 604.79 km2 were more than World Health Organization (WHO) guideline (0.05 mg/L). The Moran's index analysis showed that the distribution of contamination is a cluster. The Hazard Index (HI) values for the children and teens groups were 1.02 and 2.02, respectively, which was more than 1. A sensitivity analysis indicated that the most important factor in calculating the HQ was the concentration of chromium in the consumed water. HQ values higher than 1 represent a high risk for the children group, which should be controlled by removing the chromium concentration of the drinking water.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fct.2018.03.019DOI Listing
May 2018

Spatial variation and probabilistic risk assessment of exposure to fluoride in drinking water.

Food Chem Toxicol 2018 Mar 6;113:314-321. Epub 2018 Feb 6.

Environmental and Food Hygiene Laboratories (LIAA), Department of Medical, Surgical Sciences, and Advanced Technologies "G.F.Ingrassia", University of Catania, Italy.

Assessing the health risks of exposure to fluoride in developing countries has been unclear. In this study, the concentration of fluoride and its spatial analysis in groundwater of 6 counties of Yazd province, Iran, were investigated. Health risk assessment of three age groups (children, teens and adults), sensitivity analysis and uncertainties of effective variables were carried out using Monte Carlo simulation. The results showed that 68.77% of the samples taken were within the standard range set by the WHO guidelines (0.5-1.5 mg/l). The mean (Standard division) of fluoride in Ardakan, Azezar, Mehriz, Meybod, Taft and Yazd were 0.83 (0.31), 0.73 (0.41), 0.56 (0.20), 0.91 (0.32), 0.60 (0.32) and 0.64 (0.25) respectively. Among the studied counties, Ashkezar has the highest dispersion in terms of high concentration of fluoride. The hazard quotient (HQ) value for all age groups except children was less than 1, indicated potential of non-cancer risk of exposure to fluoride for this group. The most important variable in calculating the HQ was the drinking water ingestion rate, concentration of fluoride and the fraction of skin in contact with water, so more focused on these parameters should be made for a more accurate health risk assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fct.2018.02.001DOI Listing
March 2018

Kinetics of biogas production and chemical oxygen demand removal from compost leachate in an anaerobic migrating blanket reactor.

J Environ Manage 2018 Jan 20;206:707-714. Epub 2017 Nov 20.

Kurdistan Environmental Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran. Electronic address:

In this study, laboratory anaerobic migrating blanket reactor (AMBR) with four units was used to reduce and remove COD leachate of composting process; it was also used to determine the kinetic coefficients of COD removal and biogas and methane gas production in several different OLRs. The maximum concentration of organic matter entering the reactor was 100,000 mg/L and the reactor was under operation for 319 days. The results showed that the COD removal efficiency of AMBR in all concentrations of substrate entering the reactor was above 80%. First-order model and Stover-Kincannon were used to investigate the kinetics of COD removal via AMBR biological process; in addition, the two models of Modified Stover-Kincannon and Van der Meer and Heertjes were used to check the kinetic constants of biogas and methane gas production. The results obtained from the models showed that the experimental data on COD removal were more consistent with the results obtained from Stover-Kincannon model (R = 0.999) rather than with the First-order model (R = 0.926). Kinetic constants calculated via Stover-Kincannon model were as follows: saturation value constant (KB) and maximum utilization rate constants (U), respectively, were 208,600 mg/L d and 172,400 mg/L d. We investigated the linear relationship between the experimental data and the values predicted by the models; as compared with the values predicted by the First-order model, the values predicted by Stover-Kincannon model were closer to the values measured via experiments. Based on the results of the evaluation of kinetic coefficients of Stover-Kincannon model, with the migration of the leachate flow from unit 1 to unit 4, U value has fallen significantly. The values of maximum specific biogas production rate (G) and proportionality constant (GB) obtained from the Stover-Kincannon model, respectively, were 35,714 ml/L d and 42.85 (dimensionless) and value of kinetic constant of Van der Meer and Heertjes (ksg) was 0.0473 ml CH/mg COD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jenvman.2017.10.038DOI Listing
January 2018

Spatial analysis and health risk assessment of heavy metals concentration in drinking water resources.

Environ Sci Pollut Res Int 2017 Nov 15;24(32):24790-24802. Epub 2017 Sep 15.

Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

The heavy metals available in drinking water can be considered as a threat to human health. Oncogenic risk of such metals is proven in several studies. Present study aimed to investigate concentration of the heavy metals including As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in 39 water supply wells and 5 water reservoirs within the cities Ardakan, Meibod, Abarkouh, Bafgh, and Bahabad. The spatial distribution of the concentration was carried out by the software ArcGIS. Such simulations as non-carcinogenic hazard and lifetime cancer risk were conducted for lead and nickel using Monte Carlo technique. The sensitivity analysis was carried out to find the most important and effective parameters on risk assessment. The results indicated that concentration of all metals in 39 wells (except iron in 3 cases) reached the levels mentioned in EPA, World Health Organization, and Pollution Control Department standards. Based on the spatial distribution results at all studied regions, the highest concentrations of metals were derived, respectively, for iron and zinc. Calculated HQ values for non-carcinogenic hazard indicated a reasonable risk. Average lifetime cancer risks for the lead in Ardakan and nickel in Meibod and Bahabad were shown to be 1.09 × 10, 1.67 × 10, and 2 × 10, respectively, demonstrating high carcinogenic risk compared to similar standards and studies. The sensitivity analysis suggests high impact of concentration and BW in carcinogenic risk.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-017-0102-3DOI Listing
November 2017