Gas Chromatography Equipped With Flame Ionization Detector Research Articles

Health risk assessment of exposure to benzene, toluene, ethylbenzene and xylenes in a vehicle manufacturing industry in Iran

IntroductionConsidering the adverse carcinogenic and non-carcinogenic health effects of Volatile Organic Compounds (VOC) and specially Benzene, Toluene, Ethylbenzene and Xylenes (BTEX) which are widely used in vehicle manufacturing industry, it is clear that monitoring and control of occupational exposure to these substances is of utmost significance. More often than not the studies on occupational exposure to VOCs in vehicle manufacturing industry—specifically BTEX—have been carried out exclusively in paint shop units. The purpose of this study was to assess occupational BTEX exposure & health risk in different units of a vehicle manufacturing industry.Material and methodsFoam injection unit (FIU), gluing unit (GU), repair shop unit (RSU), molding unit (MU) as well as paint shop units (PSU) were selected for this study. Sampling and analysis were conducted based on National Institute for Occupational Safety and Health (NIOSH) 1501 guidelines by utilizing MSA personal sampling pumps set to 0.2 l/m and Gas Chromatography equipped with Flame Ionization Detector (GC-FID). Risk characterization and assessment was performed using Environmental Protection Agency Risk Assessment Information System (EPA RAIS).Results and conclusionThe results revealed that the concentration of benzene in gluing and paint shop units was above occupational exposure limits. Carcinogenic risk levels in 8 out of 10 units registered in the 1E-2 to 1E-4 range, and only two units registered a risk level below EPA’s acceptable risk level (10–6). The highest risk levels were measured in gluing, paint shop and repair shop units. Furthermore, the total non-carcinogenic hazard quotient was measured higher than 1 in 8 out of 10 studied units. Considering the abundance and wide use of VOCs -most notably BTEX- and the adverse carcinogenic and non-carcinogenic health effects of these compounds, it is advised to: change the type of paint used in paint shops, improve the existing ventilation systems, develop new and more efficient ventilation systems and conduct consistent training.

Needle extraction device for rapid and quantitative gas chromatographic determination of volatile chlorinated hydrocarbons and benzene in soil

A rapid and quantitative analytical method for volatile chlorinated hydrocarbons and benzene, such as chloroethylene, dichloromethane, and carbon tetrachloride, in soil samples was developed using a needle-type extraction device packed with activated carbon-based adsorbents. The soil sample of 10 g was placed in a glass cartridge and fixed with quartz wool to make sure not to move during the extraction process. After the internal standard solution was spiked into the soil sample, the cartridge was sealed with a polytetrafluoroethylene adapter, and the needle extraction device was used to collect the headspace gas. Analytes were purged from the soil sample and collected on the adsorbent, while pure nitrogen gas was introduced to the soil sample during the sample collection. The sampling time was approximately 10 min for 100 mL of gas sampling. After the sampling process, the extraction needle was directly inserted into a heated injection port of gas chromatography equipped with flame ionization detector (GC-FID) or that hyphenated to mass spectrometry (GC–MS). The extracted VOCs were thermally desorbed and simultaneously introduced to a GC capillary column for subsequent separation and determination. The limit of detection and limit of quantification of all the examined analytes was less than 20 and 60 ng/10 g soil in GC-FID and less than 2.5 and 7.5 ng/10 g soil in the case of GC–MS. Linear calibration curves were obtained up to 10 μg/10 g soil for all the analytes. The relative standard deviations of the ratio of analyte peak area and internal standard peak area were less than 10%. The recovery and sensitivity of analytes confirmed in the proposed method were compared with that obtained with a standard method conventionally employed.

Lipid content and fatty acid profile of commonly consumed freshwater and marine fish of Bangladesh

The objectives of this research were to determine total lipid content and corresponding fatty acid profiles in freshwater (n=10) and marine fish (n=11) samples commonly consumed in Bangladesh. Lipid was extracted by Solid Phase Dispersion method. Saponification and esterification were carried out by the association of official analytical chemists (AOAC) reference procedure with some simple modifications. The fatty acids were analyzed as their methyl ester by gas chromatography equipped with flame ionization detector (GC-FID) by comparing the retention time of 13 standard methyl ester of fatty acids. Total lipid content was 0.97-8.05% and 0.97-4.33% in freshwater and marine fish, respectively. Unsaturated fatty acid in freshwater fish was found in highest amount than saturated fatty acid. Among unsaturated fatty acids, palmitoleic acid was found in highest concentration and ranged from 46.80-26.02%. Palmitic acid was found in highest amount among saturated fatty acids and ranged from 3.96-13.91%. Among the marine fishes unsaturated fatty acids (MUFAs and PUFAs) i.e; palmitoleic acid (26.21-41.61%), oleic acid (2.35-29.63%) and linoleic acid (1.40-14.45%) were predominant. Among the saturated fatty acids myristic acid (0.97-9.08%), palmitic acid (1.61-11.35%) and stearic acid (1.03-21.53%) were found to be predominant.

A Study of the Content of Pesticide Residue in Agricultural Soils Around Federal University Gusau, Zamfara State Nigeria

In this study, the assessment of levels of pesticide residue in agricultural soil in farmlands around Federal University Gusau was carried out. The objectives of this study are to determine soil parameters such as pH, moisture content, electrical conductivity, soil organic matter content, water holding capacity, identify the pesticide residues within the study area and assess the level of pesticide residue in the soil within the area. The sampling area covered arable farmland to the north, south, west and eastern boarders of the university campus. Analyses of cleaned sample extracts were performed using Gas Chromatography equipped with Flame Ionization Detector (GC-FID). A total of twelve agricultural soil samples were taken from the location at a depth of 20cm from the topsoil. The result obtained showed the presence of organochlorine and organophosphorous pesticides. Seventeen pesticide residues and derivatives were detected. These include; 2,4 dichloro, Hexachlorobenzene (HCB), Endosulfan, Aldrin, p,p' -DDD, g- chlordane, Profenofos, Carbofuran (a carbamate), DDVP, Dichlorvos, Heptachlor, t-nonachlor, Isopropylamine, Glyphosate, Biphenyl, Dichlorobiphenyl and Lindane. Physicochemical studies of the samples gave a pH that ranges from slightly acidic to slightly basic. The results when compared with IAEA/FAO/CODEX Alimentarius guideline are observed to be within the maximum residue limit. Keywords: Pesticides, Agricultural soil, Gusau , Gas chromatography, FAO DOI: 10.7176/JEES/12-7-04 Publication date: July 31 st 2022

POLYCHLORINATED BIPHENYLS (PCBS) AND HEAVY METALS CONCENTRATIONS IN BIOTA IN SOME RIVERS IN RIVERS STATE, NIGERIA.

Pollution of aquatic environments in the Niger Delta remains a major source of food chain contamination. In this study, the concentrations of heavy metals and Polychlorinated biphenyls (PCBs) in biota were determined. Standard laboratory and environmental techniques were employed in sampling and analysis of samples. Samples were collected from Borokiri, Kaa, Okrika and Eagle Island rivers. The concentrations of PCBs were determined using gas chromatography equipped with flame ionization detector (GC-FID) while heavy metals were determined using atomic absorption spectrophotometer (AAS). The results were analyzed using descriptive and inferential techniques. The results of the study showed that concentrations of PCBs in biota ranged from 0.95 – 0.98 mg/kg. Heavy metals concentrations (mg/kg) in biota ranged as 0.848- 9.719, 4.325-6.115, 5.917-9.013, 4.369-7.395, 0.619-1.462, 3.712-5.653 and 2.911-5.614 for Cd, Cu, Zn, Cr, Ba, Pb and Ni respectively. The result shows that there is a significant difference in the concentrations of the metals in biota along the locations. While the concentrations of the PCB were within regulatory limits, there is need to consistently monitor their levels as they can contaminate the food chain thereby inducing toxicities in humans. Keywords: Polychlorinated biphenyls, heavy metals, periwinkle, concentrations, food chain, contamination. African Journal of Engineering and Environment Research Vol.3(2) 2022 ©2022 CEFPACS Consulting Limited. www. cefpacsconsultingltd.org.ng ISSN: 2635-2974

GC-MS and GC-FID analysis of volatile secondary metabolites of the root of Anaphalis contorta Hook F. from India


 ABSTRACT. The chemical composition of hydro-distilled essential oil of dried roots of Anaphalis contorta Hook F. was analyzed for the first time by using gas chromatography equipped with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The compounds of essential oil were identified according to their mass spectra and their relative retention indices determined on a capillary GC column (non-polar stationary phase). Twenty-seven compounds were identified representing 94.8% of the total oil. The major constituents were 2,2-dimethyl-2[2,4,6-trimethylphenyl] acetic acid (12.1%), labda-8,14-dien-13-ol (8.4%), δ-cadinene (8.1%), labda-7,14-dien-13-ol (6.9%), α-gurjunene (6.7%), viridiflorene (5.1%), and caryophyllene oxide (4.9%). The root essential oil of A. contorta produced different chemotypes.
 
 KEY WORDS: Anaphalis contorta Hook F., Essential oil composition, 2,2-Dimethyl-2[2,4,6-trimethylphenyl] acetic acid. labda-8,14-dien-13-ol, GC/MS
 Bull. Chem. Soc. Ethiop. 2022, 36(1), 235-240. 
 DOI: https://dx.doi.org/10.4314/bcse.v36i1.19 

Polysaccharides from Basidiocarps of the Polypore Fungus Ganoderma resinaceum: Isolation and Structure.

In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus Ganoderma resinaceum. Polysaccharide fractions were obtained by successive extractions with cold water at room temperature (20 °C), hot water under reflux (100 °C), and a solution of 1 mol L−1 sodium hydroxide. The purity of all fractions was controlled mainly by Fourier transform infrared (FTIR) spectroscopy, and their composition and structure were characterized by organic elemental analysis; neutral sugar and methylation analyses by gas chromatography equipped with flame ionization detector (GC/FID) and mass spectrometry detector (GC/MS), respectively; and by correlation nuclear magnetic resonance (NMR) spectroscopy. The aqueous extracts contained two main polysaccharides identified as a branched O-2-β-d-mannosyl-(1→6)-α-d-galactan and a highly branched (1→3)(1→4)(1→6)-β-d-glucan. Mannogalactan predominated in the cold water extract, and β-d-glucan was the main product of the hot water extract. The hot water soluble fraction was further separated by preparative anion exchange chromatography into three sub-fractions; two of them were identified as branched β-d-glucans with a structure similar to the corresponding polysaccharide of the original fraction. The alkaline extract contained a linear (1→3)-α-d-glucan and a weakly branched (1→3)-β-d-glucan having terminal β-d-glucosyl residues attached to O-6 of the backbone. The insoluble part after all extractions was identified as a polysaccharide complex containing chitin and β-d-glucans.

Total Hydrocarbon Contents: Spatial Variations in Aquatic Environment of Oyigbo Communities, Rivers State

The Total Hydrocarbon Content (THC) in fresh surface waters and sediments of Oyigbo communities in Rivers State were determined using Gas Chromatography equipped with flame ionization detector (GCFID). Fresh surface water and sediments samples were taken from different locations in four communities namely; Umuagbai, Komkom, Egberu, and Izuoma. Result of the analysis revealed thus: mean of total hydrocarbon content in surface water and sediment as 7.869±1.166 mg/L and 12.01±0.856 mg/kg respectively. The total hydrocarbon content obtained from the various locations in surface water were Umuagbai (8.529±1.208 mg/L), Komkom (9.212±1.009 mg/L), Izuoma (6.701±1.670 mg/L), and Egberu (7.034±0.778 mg/L). In sediment the total hydrocarbon content obtained were; Umuagbai (12.62±0.585 mg/kg), Komkom (16.12±1.790 mg/kg), Izuoma (8.627±0.585 mg/kg), and Egberu (10.67±0.465 mg/kg). The result showed that the sediment had more total hydrocarbon content than the surface water, which is expected because the sediment is a reservoir for the water. The sediment and surface water THC levels were lower than the WHO permissible standard which indicates low risk level. The result showed some elevated concentration especially for the sediment sample which is noticed mostly in sediments and surface waters from Komkom community samples. It is recommended that usage of the water and even consumption of fish from the said river should be limited and anthropogenic actions within the study area should be limited.

Effects of Geographic Region and Cultivar on Fatty Acid Profile and Thermal Stability of Zanthoxylum bungeanum Seed Oil.

Fatty acid profile and thermal stability of 7 varieties zanthoxylum bungeanum (GZF, GDJ, CJJ, SHY, SMN, SJY, GTS) seed oils (ZBO) were studied. Fatty acid profile, thermal stability were determined using gas chromatography equipped with flame ionization detector (GC-FID) and thermogravimetry analysis (TGA), respectively. Chemical properties, total phenolics and antioxidant activities of ZBO were determined as well. Palmitoleic acid and oleic acid (OA) were the dominant fatty acids, the ratio of ω-6/ω-3 polyunsaturated fatty acids (PUFA) of ZBO ranged from 0.66 ± 0.01 to 1.17 ± 0.01, seven varieties ZBO showed a higher thermal stability, with the 50% mass loss temperature ranged from 397.35 ± 4.02°C to 412.50 ± 2.35°C, GZF seed oil showed a balance fatty acid profile, the ratio of ω-6/ω-3 PUFA was 0.90 ± 0.01, GDJ seed oil showed a higher thermal stability, which the 50% mass loss temperature was 412.50 ± 2.35℃. These results suggested that fatty acid profile and thermal stability of ZBO were affected by cultivars and geographic region, and it may serve as a functional dietary oil.

Effects of Genetic Background and Altitude on Sugars, Malic Acid and Ascorbic Acid in Fruits of Wild and Cultivated Apples (Malus sp.).

Soluble sugars, malic acid, and ascorbic acid in 17 apple cultivars (Malus domestica Borkh.) and three wild forms (M. pumila ‘Saiwaihong’, M. prunifolia (Willd.) Borkh. and M. micromalus Makino) from three major apple cultivation regions in China were quantified using gas chromatography equipped with flame ionization detector (GC-FID). Fructose was the most abundant sugar, followed by sucrose, glucose, and sorbitol. Wild apples contain more sorbitol and less sucrose and were significantly more acidic than cultivated fruits. The total sugar content varied from 110 to 160 mg/g fresh fruits, total acid content from 2 to 6 mg/g, with a strong influence of genetic background and growth location. Overall, ‘Gala’, ‘Xiali’, ‘Liuyuehong’, ‘Lihong’, ‘Starking Delicious’, and ‘Starkrimson’ were characterized by higher sugar/acid ratio indicating sweeter taste compared to other cultivars. The wild apples had the highest content of ascorbic acid (0.6–0.96 mg/g). Compared to other cultivars, ‘Zhongqiuwang’, ‘Qinguan’, and ‘Nagafu No. 2′ were richer in ascorbic acid. The ascorbic acid content in the commercial cultivars was highly dependent on growth location. The content of malic acid and sucrose positively correlated to altitude, and that of glucose negatively. Malic acid positively correlated with ascorbic acid and sucrose, glucose content with ascorbic acid.

Microbiome Reengineering by Heat Selection for Rapid Biodegradation of Trichloroethylene with Minimal Vinyl Chloride Formation

Trichloroethylene (TCE) was a widely used industrial solvent but is now regarded as a notorious groundwater contaminant. Both physicochemical and biological methods have been applied to remediate groundwater contaminated by TCE. For medium to low level of TCE contamination, bioremediation could be more cost-effective. However, bioremediation approaches suffer from slow degradation rates and accumulation of vinyl chloride (VC). In addition, bioaugmentation is often highly encouraged but may introduce foreign genes and increase the pace of microbial evolution. In this study, a microbiome reengineering strategy by heat selection is applied to solve these problems. Out of eight heat-treated mixed cultures, two showed a much-improved TCE degradation rate, more than 70 times higher than the untreated. The biodegradation half-life (t1/2) of TCE was 0.0627 d or shorter. No VC was detected by a gas chromatography equipped with flame ionization detector (GC-FID) and only a minimal amount by a GC-mass spectrometer (GC-MS). Ethene achieved a fairly good mass balance. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and next-generation sequencing (NGS) results showed that the heating process did not kill most bacteria, but Dehalococcoides were either not present or very scarce. Acetoanaerobium and Methanosarcina could be the most important species in this reductive dechlorination process. Kinetic study results showed that the maximum specific TCE degradation rate was approximately 1,271 nmole/min/mg cell protein, which are two orders of magnitude higher than that of the mixed cultures reported in literature. These results suggest that apart from biostimulation and bioaugmentation, microbiome reengineering could be a promising approach for rapid bioremediation of TCE-contaminated aquifers.

Transforming corn stover to useful transport fuel blends in resource-limited settings

Development of local technologies is crucial to the sustainable energy agenda in resource-limited countries and the world. Strengthening local green technologies and promoting local utilization will reduce carbon emissions that could be generated during transportation and delivery of green products from one country to another. In this paper we developed bio-oil/diesel blends using a low-tech pyrolysis system designed for smallholder farmers in developing countries and tested their appropriateness for diesel engines using standard ASTM methods. Corn stover retrieved from smallholder farmers in Gayaza, Uganda were pyrolyzed in a batch rocket stove reactor at 350 °C and liquid bio-oil harvested. Bio-oil chemical composition was analyzed by Gas Chromatography equipped with Flame Ionization Detector (GC-FID). Bio-oil/diesel emulsions in ternary concentrations 5%, 10% and 20% bio-oil weight were developed with 1% concentration of sorbitan monolaurate as an emulsifier. The bio-oil/diesel emulsions and distillates had property ranges: specific gravities at 15 °C 827.4–830.7 kg m−3, specific gravities at 20 °C 823.9–827.2 kg m −3, kinematic viscosities at 40 °C 3.01–3.22 mm2/s, initial boiling points 140–160 °C, final boiling points 354–368 °C, and calculated cetane indexes 56.80–57.63. These properties of the bio-oil/diesel blends and their distillates compare well with standard transportation diesel fuel. The emulsion distillates meet the standard requirements for automotive diesel in East Africa.

POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) AND TRACE METALS IN SOME BRANDS OF SAUSAGE ROLL IN THE NIGERIAN MARKET

Background: Concentrations of PAHs and trace metals in five selected brands of sausage commonly available in the Nigerian market were determined in this study. The health risk assessment of both PAHs and trace metals were also evaluated. Methods: PAHs extraction of the sausage samples was carried out with Soxhlet extractor and clean-up of the extract was done using activated silica gel. The analysis of target analytes including the 16 priority PAHs was performed with Gas Chromatography equipped with Flame Ionization Detector (GC-FID) and the concentration of trace metals were determined using Atomic Absorption Spectrophotometry (AAS) after acid digestion of the sausage samples.Results: The amounts of Ʃ16 PAHs in sausage samples were in the range of 12.5-36.2 µg/g. All the samples investigated had concentration of Benzo (a) pyrene above 0.001 µg/g limit in processed cereal based food products stipulated by European Commission Regulation. In this study, the brands of sausages were majorly polluted with 4- and 5-ring PAHs. The concentrations (mg/Kg) of trace metals ranged as follows: Zn (1.01-71.0), Cu (ND-8.12) and Cr (ND-16.4). Cd was not detected in all the sample. Pb ranged from 2.34-13.0 mg/kg infringing the safe limit for cereals and cereal-based food products of 0.3 mg/kg and 0.05 mg/kg stipulated by FAO/WHO and European Commission, respectively. Conclusion: However, it is imperative to constantly monitor and control the concentrations of these pollutants in sausages since they are commonly consumed by Nigerian school children and youths.

Placental levels of polycyclic aromatic hydrocarbons (PAHs) and their association with birth weight of infants

As an alarming group of pollutants, polycyclic aromatic hydrocarbons (PAHs) gather much public health concern not only because of their carcinogenic or co-carcinogenic risk but also by interfering with hormone systems or by causing oxidative damage, henceforth liable to toxic actions on reproduction. Accordingly, the present study was aimed to explore the association between in-utero exposure to PAHs by evaluating their placental levels and infant birth weight among 110 healthy and nonsmoking pregnant women. Placental tissue samples were collected instantly after delivery and were analyzed for the presence of sixteen Environmental Protection Agency (EPA) listed PAHs with the help of Gas chromatography equipped with flame ionization detector (GC-FID). Chrysene and benzo(k)fluoranthene were the predominant PAHs detected in tissue samples. To assess the source of origin of PAHs in placenta tissue samples, the ratio of low molecular weight PAHs to high molecular weight (∑LMW/∑HMW PAHs) was calculated, showing the predominance of pyrogenic sources of PAHs possibly responsible for the exposure of the studied population. Results of regression analysis demonstrated the inverse although not significant association of naphthalene (Nap), acenaphthylene (Acy), anthracene (Anth), pyrene (Pyr), benzo(b)fluoranthene (BbF), benzo(k)Fluoranthene (BkF), benzo(a)pyrene (BaP), indeno (123 cd pyrene (IcdP), dibenzo(ah)anthracene (DahA) and benzo(ghi)Perylene (BghiP) with birth weight of neonates. Additionally, the regression model lay light upon the significant association of fluoranthene (Fla) (coefficient= −1.41 gram, p < 0.05) to the depletion trend of birth weight after adjusting for potential covariates. These findings suggest the possible role of an environmental contaminants like PAHs on impairment of fetal growth.

Premna odorata: Seasonal Metabolic Variation in the Essential Oil Composition of Its Leaf and Verification of Its Anti-Ageing Potential via In Vitro Assays and Molecular Modelling.

The metabolic variation in the essential oil composition of Premna odorata leaves obtained from different seasons was quantitatively and qualitatively determined employing GC/MS (Gas Chromatography coupled with Mass Spectrometry) and GC/FID (Gas chromatography equipped with flame ionization detector) techniques. It displayed the existence of 97 constituents accounting for 94.19%, 92.27%, 91.95% and 92.63% for POS (spring), POM (summer), POA (autumn) and POW (winter) whole essential oils. β-Caryophyllene constituting the main metabolite in the oil in the different seasons. To better visualize the differences between them, GC data were exposed to chemometric analysis. A PCA (principal component analysis) score plot revealed the closeness of POS and POW. Molecular modelling on collagenase, elastase and hyaluronidase enzymes active centres shows that different compounds existing in the essential oil of Premna odorata leaves shows binding to the active sites with variable degrees that suggested its anti-ageing potential. Palmitic acid displayed the highest fitting for both the collagenase and elastase active centres in both pH-based and rule-based ionization methods with ∆G equals −78.27 and −44.77 kcal/mol, respectively; meanwhile, heptacosane showed the highest fitting score in the hyaluronidase centre with ∆G = −43.78 kcal/mol. In vitro assays consolidates the obtained modelling studies in which essential oil shows considerable anti-elastase and anti-hyaluronidase potential as evidenced by their IC50 values being 49.3 and 37.7 μg/mL, respectively; meanwhile, the essential oil of Premna odorata leaves displayed mild anti-collagenase potential. Thus, it can be concluded that Premna odorata could serve as a promising anti-ageing naturally occurring drug that could be effectively incorporated by pharmaceutical industries in cosmetics combating ageing and skin wrinkling.

Volatile Constituents of Emilia sonchifolia from India

The volatile constituents were isolated by hydro-distillation of the aerial parts of Emilia sonchfolia (L.) DC. (Asteraceae). The constituents were analyzed for the first time by gas chromatography equipped with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC/MS). Forty-three compounds were identified, representing 96.3% of the total oil. The major constituents were γ-muurolene (32.1%) and β-caryophyllene (22.7%). The other minor constituents were ( E)-β-ocimene (4.0%), α-muurolene (3.9%), δ-cadinene (3.7%) and epi-α-cadinol (3.7%). The oil was found to be rich in sesquiterpene hydrocarbon (67.6%) type constituents.

Risk assessment of benzene in food samples of Iran's market

The concentration of benzene in ninety-eight collected food and drink samples (carbonated beverage, fruit juice, pickle, lime juice, mayonnaise and salad dressing, 16 samples from each) from Iran local markets were investigated using gas chromatography equipped with flame ionization detector (GC-FID). Moreover, the correlation of benzene concentration with sodium benzoate and ascorbic acid concentrations was assessed. Benzene concentration in carbonated beverages, fruit juices, pickle, lime juices, mayonnaise and salad dressing were 3.57 ± 1.70, 5.17 ± 3.63, 4.37 ± 2.24, 4.99 ± 0.54, 1.38 ± 0.87 and 1.47 ± 0.83 μg/L, respectively, being in all cases below the acceptable limit (10 μg/L) proposed by the World Health Organization (WHO) as a reference for drinking water. Benzene concentration exceeded the maximum tolerable limit in 12.5% of carbonated beverages and fruit juices (two samples from each). A significant correlation coefficient between the concentrations of benzene, sodium benzoate, and ascorbic acid in fruit juices, and levels of benzene, sodium benzoate in carbonated beverage samples was observed. To characterize the risk of exposure of urban and rural consumers of Iran (female in age group of 15–24 and male in age group of 25–64) to benzene in food and drink samples the Margin of Exposure (MoE) approach was applied revealing there is no severe concern regarding benzene intake through assessed food and beverages samples in Iran.

Chemical Composition of the Essential oil of Syzygium kanarense: An Endemic and Rediscovered Species from the Western Ghats, India

The hydro-distilled essential oil obtained from the aerial parts of Syzygium kanarense(Talbot) Raizada (Myrtaceae) was investigated for the first time by gas chromatography equipped with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC/MS). Fifty-two constituents were identified, which represented 91.9% of the total oil. The major compounds were seychellene (7.3%), α-muurolol (5.4%), cis-cadinene ether (5.3%), β-vetivenene (5.1%), 10 epi-γ-eudesmol (4.8%), guaiol (4.5%), longiborneol (4.1%), δ-elemene (4.1%) and α-muurolene (4.1%). The oil was found to be rich in sesquiterpene hydrocarbon (49.5%) type constituents.

Characteristics of PrekotAC as Formulated Filter Aids and Its Performance to Adsorb Volatile Organic Compound

The characteristics of a formulated filter aids material known as PrekotAC which is a combination of an adsorbent, activated carbon with a pre-coating material was investigated in this study. PrekotAC, was formulated into two different weight ratios of 5:95 and 10:90 respectively. The relationship between the adsorption properties and the characteristics of the formulated materials in terms of its particle size distribution, particle density, bulk density, moisture content as well as its BET surface area was investigated. A specific amount of 100mg of formulated filter aids was placed in a fixed glass tube and subjected to a given concentration of toluene at the temperature of 25°C and 1.0 l pm gas flow rate. The adsorption properties of each filter aids material was tested under various time where the amount of toluene adsorbed by the filter aids was analysed using gas chromatography equipped with flame ionization detector (GC-FID). The ability of the formulated filter aids to adsorb toluene was presented and discussed in this paper.

Chemical Composition and Antibacterial Activity of the Essential of Cedrus atlantica (Cedarwood oil)

The purpose of this study was to determine the chemical composition and antibacterial activity of the Moroccan Cedarwood essential oil. The sawdust samples of Cedrus atlantica were collected from Azrou, located in the heart of The Middle Atlas region of Morocco. The plant samples were subjected to hydrodistillation for eight hours. The oils were then analysed by Gas Chromatography equipped with flame ionization detector (GC-FID) and Gas chromatography coupled with Mass spectrometry (GC-MS). The antimicrobial activities were tested in vitro on gram-negative bacteria Escherichia coli and Salmonella, as well as gram-positive Staphylococcus aureus, Bacillus subtilis and Bacillus cereus using the agar diffusion assay/aromatogramme and minimum inhibitory concentration (MIC). Three bacterial strains (Escherichia coli, Bacillus subtilis and Bacillus cereus) were found to be sensitive to cedarwood essential oil and showed effective bactericidal activity with a Minimum Inhibitory Concentration of 0,4 μl/ml for Escherichia coli and Bacillus cereus, and 0,2 μl/ml for Bacillus subtilis.