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Illegal and excessive use of veterinary antibiotics as a food additive for growth promotion in livestock can lead to allergic reactions and antibiotic resistance, which is a worldwide concern. A biochip-based semi-quantitative screening method of antimicrobial residues in milk was validated based on Commission Decision 2002/657/EC and the European guideline to validate screening methods for veterinary medicines. This multi-analytical screening method enables to determine of 3 beta-lactams (cefalexin, ampicillin, and cefuroxime) simultaneously. Analysis of 20 blank and 20 spiked milk samples showed that for all 3 antibiotic residues, the positivity threshold T was above cut-off value Fm, and no false-positive results were obtained for all 3 antibiotics. All detection capabilities (CCβ) were below Maximum Residue Level (MRL) authorized by European Commission. 47 UHT cow's milk samples collected from Tehran province, IR Iran, were screened, and compliance was found in 100% of samples. This study found that the biochip method is valid to determine antibiotic residues in milk samples at the measured validation levels. The method was fast, simple, and able to simultaneous screen three families of beta-lactams from a single milk sample with almost no sample preparation. [ABSTRACT FROM AUTHOR]

Pesticide residues in fruits and vegetables are one of the highest concerns of consumers who need food safety. In this study, forty-eight pesticide residues from different chemical structures including organochlorine, organophosphorus, organonitrogen, dicarboximides, strobilurin, triazine, pyrethroids, and other chemical groups. In 85 fruits and vegetables were determined and confirmed by GC-MS. The pesticide was extracted with ethyl-acetate, then, the extracts cleaned using high performance gel permeation column chromatography (GPC) and solid phase column (SPE). The mean recoveries of the pesticides were between 81 and 136%. The reproducibility of the relative standard deviation values was 2.1% and 14.8%. Pesticide residues were more frequently found in vegetables (65.5%) than in fruits (26.7%). The limits of detection and quantification of pesticide residues for the method were ranged from 0.003 to 0.06 μg/g and between 0.01 to 0.1 μg/g respectively. The analyzed samples did not contain residues from the monitored pesticides that were higher than the accepted maximum residue limits (MRLs) as adapted by the FAO/WHO Codex Alimentarius Commission. [ABSTRACT FROM AUTHOR]

Background: Drivers are vulnerable to musculoskeletal and psychological disorders because of substantially harmful agents in this stressful occupation. This study aims to investigate the influence of driver's physical and psychological health on the risk of road accidents using fuzzy logic approach. Methods: Two input variables including musculoskeletal disorders (MSDs) and mental health, alongside accident risk levels as output variables were fuzzed using a fuzzy inference system (FIS). Triangular and trapezoid membership functions were used to graphically define outputs related to low, moderate, high and very high, in fuzzy sets. A Mamdani-type FIS was applied to represent all the rules in the IF-THEN format and the patterns of linguistic variables were designed using AND, OR and NOT operators. Results: The results showed that there is significant relationship between MSDs and psychological health with road accidents involving drivers of heavy vehicles (p<0.05). Also, surface graphs illustrated the relationship between MSDs, psychological health and accident risks. FIS as a novel approach was used for predication of accident risk levels involving drivers of heavy vehicles on the basis of health factors. Conclusions: Physical and psychological health can influence the safe operation of heavy vehicle drivers. The fuzzy inference system provided a method that is advantageous and with promising results for modeling of road accident risk levels on the basis of driver's physical and mental health. [ABSTRACT FROM AUTHOR]

A fast and simple modified QuEChERS (quick, easy, cheap, rugged and safe) extraction method based on spiked calibration curves and direct sample introduction was developed for determination of Benzo[a]pyrene (BaP) in bread by gas chromatography-mass spectrometry single quadrupole selected ion monitoring (GC/MS-SQ-SIM). Sample preparation includes: extraction of BaP into acetone followed by cleanup with dispersive solid phase extraction. The use of spiked samples for constructing the calibration curve substantially reduced adverse matrix-related effects. The average recovery of BaP at 6 concentration levels was in range of 95-120%. The method was proved to be reproducible with relative standard deviation less than 14.5% for all of the concentration levels. The limit of detection and limit of quantification were 0.3 ng/g and 0.5 ng/g, respectively. Correlation coefficient of 0.997 was obtained for spiked calibration standards over the concentration range of 0.5-20 ng/g. To the best of our knowledge, this is the first time that a QuEChERS method is used for the analysis of BaP in breads. The developed method was used for determination of BaP in 29 traditional (Sangak) and industrial (Senan) bread samples collected from Tehran in 2014. These results showed that two Sangak samples were contaminated with BaP. Therefore, a comprehensive survey for monitoring of BaP in Sangak bread samples seems to be needed. This is the first report concerning contamination of bread samples with BaP in Iran. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are classified as persistent and carcinogenic organic pollutants. PAHs contamination has been reported in water. Many of relevant regulatory bodies such as EU and EPA have regulated the limit levels for PAHs in drinking water. In this study, 13 priority polycyclic aromatic hydrocarbons (PAHs) were determined in tap water samples of Tehran and water for injection. Dispersive liquid-liquid microextraction procedure combined with gas chromatography-mass spectrometry was used for the extraction and determination of PAHs in the samples. Under the optimized conditions, the range of extraction recoveries and relative standard deviations (RSDs) of PAHs in water using internal standard (anthracene-d10) were in the range of 71-90% and 4-16%, respectively. Limit of detection for different PAHs were between 0.03 and 0.1 ngmL-1. The concentration of PAHs in all tap water as well as water for injection samples were lower than the limit of quantification of PAHs. This is the first study addressing the occurrence of PAHs in water for injection samples in Iran using dispersive liquid-liquid micro extraction procedure combined with gas chromatography-mass spectrometry. [ABSTRACT FROM AUTHOR]

BACKGROUND: According to the growth of photocopier usage in workplaces, the potential risk of occupational exposure to the airborne chemicals has been raised up. Hence, monitoring the photocopy worker's respiratory functions seems to be necessary. We aimed to evaluate the respiratory health on photocopy and printing workers so that a reliable description can be made about their occupational hygiene. METHODS: This study was performed in Shiraz, southwest Iran in 2014 and a group of 150 photocopy and printing workers were surveyed as exposed group in addition to a group of 114 office staff as unexposed group. The respiratory standard questionnaire was used to evaluate the prevalence of respiratory symptoms among the selected staff. Pulmonary function indexes including VC, FVC, FEV1 and the FEV1/FVC ratio were calculated. Finally, t-test, Chi Square and multiple logistic regressions were conducted. RESULTS: VC, FVC and FEV1 in photocopy and printing workers were lower than the unexposed group of which these differences for FVC and FEV1 were statistically significant (P CONCLUSIONS: The prevalence of excess respiratory symptoms along with pattern of pulmonary restrictive sings in photocopy and printing workers revealed that the workplace conditions can result in occupational respiratory diseases. [ABSTRACT FROM AUTHOR]

A fast and simple modified QuEChERS extraction method was developed for determination of Benzo[a]pyrene (BaP) in 137 traditional (Sangak), semi-industrial (Sangak) and industrial bread samples using spiked calibration curves by GC/MS. Sample preparation includes extraction of BaP into acetone followed by cleanup with dispersive solid phase extraction. The limit of detection and limit of quantification were 0.3 ng/g and 0.5 ng/g, respectively. The values for recoveries and RSD were calculated as 110.5-119.85% and <11.6% respectively. Average concentration of BaP in Sangak bread samples of Shiraz and Tehran was 0.59 and 0.60 ng/g, respectively. 35.5% of samples of breads collected in Tehran were contaminated with BaP at the amount higher than maximum levels regulated in processed cereal-based foods and baby foods by European Commission (1 ng/g). Seventeen percent of samples of breads collected in Shiraz were contaminated with BaP which 13 % of total samples were >1 ng/g. BaP content in all industrial samples was lower than LOQ. Assuming the consumption of bread in Tehran and Shiraz is limited to these kinds of breads, the daily intake of BaP in Tehran and Shiraz population through bread consumption was estimated to be 170.6 and 168.7 ng/day, respectively. This is the first report concerning contamination of bread samples with BaP in Iran. [ABSTRACT FROM AUTHOR]

Dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography-mass spectrometry (GC-MS) was used for the extraction and determination of 13 polycyclic aromatic hydrocarbons (PAHs) in mineral water samples. In this procedure, the suitable combination of extraction solvent (500 µL chloroform) and disperser solvent (1000 µL acetone) were quickly injected into the water sample (10.00 mL) by Hamilton syringe. After centrifugation, 500 µL of the lower organic phase was dried under a gentle stream of nitrogen, re-dissolved in chloroform and injected into GC-MS. Chloroform and acetone were found to be the best extraction and disperser solvent, respectively. Validation of the method was performed using spiked calibration curves. The enrichment factor ranged from 93 to 129 and the recovery ranged from 71 to 90%. The linear ranges for all the PAHs were 0.10-2.80 ngmL-1. The relative standard deviations (RSDs) of PAHs in water by using anthracene-d10 as internal standard, were in the range of 4-11% for most of the analytes (n = 3). Limit of detection (LOD) for different PAHs were between 0.03 and 0.1 ngmL-1. The method was successfully applied for the analysis of PAHs in mineral water samples collected from Tehran. [ABSTRACT FROM AUTHOR]

Veterinary drugs are extensively and legally consumed to treat and prevent disease in chattels but some are also used illegally as growth-stimulating agents. Inappropriate or intensive use of antibiotics can cause allergic reactions and, above all, antibiotic resistance. A multiclass approach for the screening of antimicrobial substances in milk was validated in consonance with Commission Decision 2002/657/EC and to the European guideline for the validation of screening methods for veterinary medicines. This biochip-based approach enables the simultaneous determination of a total of 13 sulphonamide, dapsone and trimethoprim. For monitoring of antibiotic residues, 53 UHT milk samples collected from Tehran, IR Iran were screened applying this technology. The result showed that for all antibiotic residues, the positivity threshold T was much more than the cut-off value Fm. A false positive rate of less than 5% was found for all antibiotics which are satisfactory. All detection capabilities (CC β ) were well below the Maximum Residue Level (MRL) set by the European Commission (100 µ g/kg for the sum of all sulphonamides and 50 µ g/kg for trimethoprim in milk). The screening results of 53 milk samples showed that 71.7% of samples were compliant and all positive samples were below the MRL set by European Commission. This study showed that the biochip-based technique is valid to identify and quantify antibiotic residues in milk at the studied validation levels. The method was rapid, easy, safe, and able to screen 13 sulphonamide, dapsone and trimethoprim from a single milk sample simultaneously with no sample preparation procedure (or just one-step centrifugation).