Concentration and Source Assessment of Polycyclic Aromatic Hydrocarbons in the Street Soil of Ma'an City, Jordan.

In this study, the levels of polycyclic aromatic hydrocarbons (PAHs) were determined in the street soil of Ma'an City, Jordan. The probable sources of PAHs in the soils were estimated by using diagnostic ratios. PAHs were extracted from soil samples via the ultrasonic extraction method using three portions of 20 mL of n-hexane/acetone mixture. The most priority environmental protection agency 13 PAHs were determined in the extract using gas chromatography-mass spectrometer. The results showed that average concentrations of ∑13PAHs ranged from 77.0 to 917.4 ng/g, and the 3- and 4-rings PAHs were the most abundant PAHs detected in the soil samples (~ 60% of the PAH total concentrations). The ratios showed that the PAHs in Ma'an's street soil have both petrogenic and pyrogenic sources. Pearson's correlation coefficient analysis showed that the content of ∑13PAHs is directly correlated to the total organic matter (TOM) in the soil. Analysis of variance indicated that Ma'an city mostly had the same sources for ∑13PAHs.

Evaluation of Dioxin/Furan and Elements in Poultry from Zarqa Governorate, Jordan.

This study is the first to determine the concentration for 17 congeners of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and element contamination in poultry that is close to petroleum refinery at Al-Hashemiya Municipality, Zarqa Governorate, Jordan. Ten different samples (chicken) were collected to cover ten different locations of poultry farms in Al-Hashemiya Municipality. These locations are considered polluted areas as a result of exhaust gases produced from the refinery. The 17 PCDD/Fs congeners and elements of Pb, Cd, As, Zn, Cu, Se, Hg, Cr, and Ni were determined for three parts of each sample (liver, muscle, and gizzard). All samples were analyzed for PCDD/Fs after a Soxhlet extraction procedure and cleanup by column chromatography; then, all compounds were identified and determined using GC-MS techniques. The elements were analyzed after digestion and measured using an inductively coupled plasma optical emission spectrometer (ICP-OES) and validated with the Lab Mix24 RM NCS ZC73016 reference material. The highest total sum concentration of PCDD/Fs was found in liver samples to be 214.07 ng/kg (dry weight), while the highest sum of toxicity equivalent to PCDD/Fs of 22.54 ng TEQ/kg was found in gizzard samples. For element concentrations, the highest total sum of 16.89 mg/kg (dry weight) was found in liver samples. The concentration level of the elements of Se, Hg, Cr, and Ni for all parts of the chicken was within an acceptable range according to Jordanian standards and therefore the measured level of heavy and trace elements in the poultry samples (chicken) does not pose a danger to public health. The chickens found in poultry farms near the refinery are more likely to contain a higher concentration of PCDD/Fs congeners due to exhaust gas exposure.

Optimizing Reductive Degradation of PAHs Using Anhydrous Ethanol with Magnesium Catalyzed by Glacial Acetic Acid.

Targeted degradation of individual polycyclic aromatic hydrocarbon (PAH) constituents like anthracene, may offer cost effective and efficient cleaning of coal tar-contaminated sites. Thus, a reductive degradation procedure of anthracene using activated magnesium with anhydrous ethanol at room temperature was developed and optimized. To determine the optimum conditions for anthracene, such as effective magnesium concentrations, glacial acetic acid volumes, and exposure time for the anthracene reduction, the experiments were designed using the response surface methodology based on the central composite design. The design also minimized the number of experiments. The main product from anthracene reduction is 9,10-dihyrdoanthracene. Optimum conditions for 98% degradation capacity of anthracene (2.80 × 10-3 mmol) were 30 mg of Mg powder (1.20 mmol), 60 µL of glacial acetic acid (1.05 mmol), and 30 min exposure time. When the optimized method was tested on the coal tar specimen, twice as many reagents (i.e., Mg and glacial acetic acid) were required to obtain a 90% degradation of anthracene and fluoranthene from the coal tar. This method of using activated Mg and anhydrous ethanol selectively reduces PAHs in coal tar; in particular anthracene and fluoranthene are most efficiently removed.