Search published articles


Showing 4 results for Carcinogenic
The potential of cyanobacterium Schizothrix vaginata ISC108 in biodegradation of crude oil
M Safari, S Ahmady-Asbchin, N Soltani,
Volume 7, Issue 3 (5-2014)
Abstract

Background and Objective: Petroleum hydrocarbons are a bunch of pollutants hazardous to the environment. Nowadays, biodegradation of petroleum contaminants is considered as one of the most efficient and most cost effective methods of removing oil contamination from the environment. The main objective of this study is to investigate the potential of cyanobacterium Schizothrix vaginata ISC108 in the biodegradation of crude oil and to evaluate oil effects on growth rates, dry weight, and chlorophyll content. Material and Methods: In this experimental study, the cyanobacterium Schizothrix vaginata ISC108 was obtained from the algal culture collection of Research Institute of Applied Science, ACECR, Tehran, Iran. First, purification of the cyanobacterium was performed using agar plate method on solid medium of BG11. Growth rate, chlorophyll content and dry weight of cyanobacteriaum was measured using spectrophotometry method. The biodegradation rate of crude oil was calculated using gas chromatography (GC) analysis. Results: Measuring the growth rate of cyanobacterium Schizothrix vaginata at 1% treatment of crude oil and control samples showed that the growth of cyanobacterium in the presence of crude oil as the sole carbon source increases at the same rate as the control sample. Moreover, it was found that increasing the concentration of crude oil will result in increasing dry weight of Schizothrix vaginata however, and the chlorophyll content reduced in various crude oil treatments. The average biodegradation of petroleum hydrocarbon after 14 and 28 days of treatment was 54.78 and 93.98% respectively. Conclusions: It was found that cyanobacterium Schizothrix vaginata ISC108 has great potential in biodegradation of crude oil. Therefore, since oil is a product toxic to biological systems and is one of the main pollutants of bioecosystem, it has a great potential to be used as an indicator to eliminate pollution in contaminated areas.


Semi-Quantitative and Quantitative Health Risk Assessment of Gas Station Workers Exposure to Benzene
M Zare Jeddi, M Yunesian, R Ahmadkhaniha, H Kashani, N Rastkari,
Volume 8, Issue 3 (12-2015)
Abstract

Background and Objective: One of the air pollutants is volatile organic compounds (VOCs). Benzene, as a part of petrol, is a VOC, known to be carcinogenic to human beings (Group 1) and it has widespread application in  various industries and professions. Hence, the aim of the present study was semi-quantitative and quantitative health risk assessment of petrol bank workers exposure to benzene via inhalation in the Tehran, Iran.

Material and method: For these purpose, this descriptive cross-sectional study was conducted in three stages. First stage consisted of measurement of benzene in two groups of participants: (1) petrol bank workers and (2) non-exposed people as control group. The second stage included the evaluation of worker's exposure to benzene and semi-quantitative risk assessment, and the third stage was estimating the lifetime cancer risk caused by exposure to benzene.

Results: Benzene mean concentration was near the threshold limit value (1600 µg/m3) and the mean benzene personal air level was 1527±246.4 µg/m3 in the petrol bank areas. With regard to semi-quantitative risk assessment method, benzene introduced as the most hazardous chemical with risk ratio of 4.5 has 5th rank in risk levels (Extremely dangerous). Lifetime cancer risk estimation showed that in petrol bank workers the excess lifetime cancer risk was 27.5 times higher than unexposed group and the chance of cancer was one in a 1000 petrol bank workers.

Conclusion: This study indicates that petrol bank workers in Tehran have a potentially high cancer risk through inhalation exposure. Thus, preventative actions regarding to this hazardous and carcinogenic chemical must be started as soon as possible.


Human health risk assessment of heavy metals in street dust in Abadan
N Ghanavati,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: The aim of the present study was to investigate risk of heavy metals on human health including (Pb, Zn, Cu, Cr, Cd, Ni, V, As and Co) in street dusts in Abadan.
Materials and Methods: 30 dust samples were collected from sidewalks of main streets of Abadan and analyzed by inductively coupled spectroscopy (ICP-OES) method.
Results: The mean concentration of the heavy metals was as follows: Pb (59.13), Zn (287.50), Cu (112.97), Cr (50.30), Cd (0.52), Ni (56.77), V (35.83), As (10.7) and Co (7.33) (mg/kg). The concentration of all of the heavy metals, except V, in the dust samples was several times higher than the field concentration (concentration in the earth's crust). The average value of the potential ecological risk of the heavy metals V, Cr, Zn, Ni, As, Cu and Pb was low and had a low potential ecological risk. Cd had a moderate potential ecological risk. Also, based on the average value of Risk Index, the samples were at medium risk. Cumulative non-carcinogenic hazard of all the heavy metals in the street dust was higher for children than adults. This indicates that children are more at risk for heavy metals than the adults. In both age groups, Cr had the highest risk of carcinogenicity and Pb had the lowest risk.
Conclusion: The results indicated that the main source of the heavy metals in the study area is anthropogenic sources such as traffic, industrial facilities and burning of fossil fuels.
 

Assessment of carcinogenic and non-carcinogenic risk of heavy metals in edible vegetable oils from Sabzevar, Iran
Hadi Niknejad, Ehsan Manavipour, Musa Cheshmi, Vajihe Hasanzadeh, Roghayeh Abedi Sarvestani, Fatemeh Ahmadi, Mehrnoosh Abtahi,
Volume 18, Issue 2 (9-2025)
Abstract
Background and Objective: Heavy metal contamination in vegetable oils is a major food safety concern due to its potential adverse effects on public health. This study aimed to measure the concentrations of heavy metals (As, Pb, Cu, and Fe) in various types of vegetable oils and to assess the associated health risks from human consumption.
Materials and Methods: In this study, 72 samples of vegetable oils—including sesame, sunflower, and rapeseed—were systematically collected from markets in Sabzevar. The oil samples were accurately weighed and digested using a mixture of nitric acid, sulfuric acid, and hydrogen peroxide. The resulting digested solutions were filtered and analyzed for Pb, As, Cu, and Fe concentrations using microwave plasma atomic emission spectrometry (MP-AES). All procedures were performed in triplicate, following national Iranian standards. To accurately evaluate health risks, the hazard quotient (HQ) for non-carcinogenic effects and the lifetime cancer risk (LTCR) were calculated using Monte Carlo simulation (MCS). A daily intake of 0.227 kg of vegetable oils was assumed, based on national dietary data, to estimate chronic exposure.
Results: The results showed that the highest levels of heavy metals in vegetable oils were as follows: Pb (0.058 mg/kg) in sesame oil, As (0.090 mg/kg) in sunflower oil, and Cu and Fe (0.143 mg/kg and 0.847 mg/kg, respectively) in rapeseed oil. The Target Hazard Quotient (THQ) values for Pb (THQ = 0.146), Cu (THQ = 0.022), and Fe (THQ = 0.01) were within the safe range. However, the THQ for As (THQ = 1.905) was found to be significantly elevated. The cancer risk assessment indicated that the consumption of these oils is generally within the acceptable risk range, but the risk associated with As was estimated to be approximately 100 times higher than that of Pb.
Conclusion: The results of this study suggest that, although the carcinogenic risk associated with vegetable oil consumption is low, continuous monitoring of these products—particularly for heavy metal contaminants—is essential to ensure consumer safety.
 

Page 1 from 1     

© 2026 , Tehran University of Medical Sciences, CC BY-NC 4.0

Designed & Developed by: Yektaweb