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Showing 5 results for Gas Chromatography
Migration of bisphenol A and nonylphenol from mineral water bottles and disposable plastic containers into water at different temperatures
Ali Kazemi, Habibollah Younesi, Nader Bahramifar,
Volume 6, Issue 4 (3-2014)
Abstract
Background and Objectives: bisphenol A and nonylphenol are xenoestrogen materials used as a monomer of plastics in widely volume in the production of plastic materials especially mineral water bottles and disposable plastic containers. In this study, we investigated the potential of migration of bisphenol A and nonylphenol from disposable plastic containers into water at different temperatures and also from mineral water into water at different temperatures. Materials and Methods: We conducted bisphenol A and nonylphenol extraction from each sample through liquid-liquid extraction. For identification and quantitative determination of bisphnol A and nonylphenol, we used gas chromatography equipped with mass detector, and for quantitative determination of these two compounds, we used high-performance liquid chromatography equipped with fluorescence detector. Results: We found that increasing temperature increased significantly the rate of migration of these two compounds in the water. Moreover, it was revealed that only the presence of bisphenol A in water of mineral water bottles was detected and the increase in temperature also increases the rate of migration bisphenol A into water. Conclusion: In general, results of this study showed that improper storage of mineral water bottles and also use of disposable plastic containers for hot drinks would result in increasing consumer exposure to these compounds.
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.


Determination of organochlorine pesticide residues in the raw milk taken from milk collection centers in Urmia in 2020
Naiema Vakili Saatloo, Tooraj Mehdizadeh, Javad Aliakbarlu, Rahele Tahmasebi,
Volume 14, Issue 2 (9-2021)
Abstract
Background and Objective: Milk is one of the most important components of human food. In recent decades, the continued use of pesticides has led to contamination of soil, water, air and milk and caused public concern in the community. Long-term exposure to pesticide residuals in the food chain can be harmful. Therefore, there is a need to control environmental conditions in order to improve its healthy and sustainable food processing practices.
Materials and Methods: In this study, 30 samples of raw milk were randomly collected in October 2020, from milk collection centers in Urmia and the residual pesticides were determined using gas chromatography–mass spectrometry (GC-MS).
Results: Organochlorine pesticides were detected in some raw milk samples. The highest concentrations of Lindane (γ-HCH) were detected with the values ranging from 0.3 to 0.6 mg/kg in 5 milk samples. Atrazine was detected in 15 samples with the values ranging from 0.8 to 1.33 mg/kg and alachlor was found in 13 samples with the varied range of 0.35 to o.5 mg/kg. Organochlorine pesticide concentrations were higher than maximum residue level (MRL) in all contaminated milk samples according to the values mentioned by the European Union.
Conclusion: This study showed that atrazine, lindane and alachlor were higher than MRL according to European Commission (EC). However, other organochlorine pesticides such as Heptachlor, Aldrin and hexachlorocyclohexane (HCH) isomers (α, β and γ) were not detected.

Fate of pesticide residues during the grape (Vitis vinifera L.) juice production
Alireza Rahimi, Nabi Shariatifar, Ali Heshmati,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: The Pesticides used in agriculture have caused great concern due to their adverse effects on human health. In this study, the effect of rinsing, crushing, filtering, clarifying with bentonite and pasteurization on the reduction of diazinon, ethion and phosalone during Asari grape juice was investigated.
Materials and Methods: Vineyard was sprayed during three growth stages before flowering, sour grape (ghooreh) and during grape ripening with phosalone, diazinon, ethion and in doses of 525, 600, 750 g of active substance per hectare, respectively. Twenty-four hours after the last spraying step, the grape sample was harvested and exposed to the process of rinsing (20-30 s), crushing, filtering, clarifying and pasteurizing. Then, the pesticides residue concentration was determined after each step by GC-MS/MS.
Results: The initial concentrations of diazinon, ethion and phosalone in unprocessed grape samples were 0.640, 0.716 and 0.550 mg/kg, respectively. The reduction values of diazinon during the juicing processes of rinsing, crushing, filtering, clarifying with bentonite and pasteurization, in comparison with the concentration of unprocessed grapes, were 25.72, 41.96, 74.54, 90.21 and 100% (not found), respectively; while these values were 9.78, 28.50, 69.45, 89.38 and 96.74% for ethion and 17.32, 28.47, 46.40, 80.25, 93.28% for phosalone, respectively. All processes significantly reduced insecticides residue.
Conclusion: Findings showed that the processes of grape juice production could significantly decrease the diazinon, ethion and phosalone residues.

Measurement of polycyclic aromatic hydrocarbons in canned fish using multi-walled magnetized carbon nanotube and solid phase extraction method
Gholamali Sharifiarab, Mohammad Ahmadi, Nabi Shariatifar, Peiman Ariaii,
Volume 16, Issue 1 (6-2023)
Abstract
Background and Objective: polycyclic aromatic hydrocarbons (PAHs) are compounds with high carcinogenic and mutagenic potential. This study aims to investigate the amount of 16 of these compounds in different types of canned fish.
Materials and Methods: In this research, first, multi-walled carbon nanotubes were magnetized by the MSPE method, and then the synthesized composite was used to extract PAHs from the matrix of canned fish samples. Finally, the concentration of each of these compounds was measured by GC-MS.
Results: The results of this research showed that the highest average amount of total PAHs and PAH4 were 20.22±5.29 and 6.07±1.41 μg/kg, respectively. Also, the highest average amount of benzo[a]pyrene (BaP) found in all samples was 1.34±0.41 μg/kg, which was lower than the existing standards (EU standard for BaP in fish is 2 μg/kg). The amount of these compounds in different types of canned fish were as follows: canned in olive oil > canned with dill > simple canned fish > canned in salt water. And finally, the amount of these compounds in brand A was higher than in other brands.
Conclusion: Based on the findings of this research and since the total average of each of these compounds is lower than the existing standards in different types of canned fish, it can be said that there is no danger to the consumers.
 

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