Street dust contamination by heavy metals in babylon governorate, Iraq

Due to the rapid population growth, advanced technology and continued urbanization worldwide, heavy metals are emitted into the ecosystem and cause negative impacts on health. This study represents the determination of street dust heavy metals copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), nickel (Ni) and chromium (Cr) in thirty sites in Babylon governorate, Iraq and investigates the possible sources of the pollution. The analysis was carried out by using flame atomic absorption spectrophotometer after the digestion process. The average concentration of Cu, Pb, Zn, Cd, Ni and Cr in the street dust were found to be 130.9, 201.4, 253.3, 2.2, 49.1 and 69.1 mg/kg, respectively. After performing a comparison with the mean of worldwide scale and values for uncontaminated soil, the findings indicated that there were high heavy metals concentrations in all sites. The main cause is the increased traffic across all areas which makes the vehicles disposed of different elements in the street dust. Moreover, the absence of regulation and lack of basic sewer and rain networks play a significant role to increase the heavy metals concentrations in the city. This research promotes a baseline data for heavy metals pollution in Babylon street dust which could afford to policymakers in order to adopt urgent environmental management strategies such as increasing green area and implementing new technologies to reduce environmental risks

Polycyclic Aromatic Hydrocarbons (PAHs) in Urban Street Dust Within Three Land-Uses of Babylon Governorate, Iraq: Distribution, Sources, and Health Risk Assessment

This study is considered to be the first investigation of 16 polycyclic aromatic hydrocarbons (PAHs) in terms of distribution and sources identification for three land-use in Babylon governorate, Iraq. Potential sources of 16 US EPA priority PAHs were identified by employing diagnostic ratio as well as principal component analysis (PCA) method. Additionally, Incremental Lifetime Cancer Risk (ILCR) model was determined in order to assess the risk exposure to the individual PAHs in street dust (SD). Findings in three land-use indicated that the total sixteen PAHs concentrations in the samples were 555.9, 1388, 1221.8 µg Kg−1 for Residential Area, Industrial Area, and Commercial area, respectively, with an average of 1055 µg Kg−1. Moreover, study findings pointed out that the percentages of both LMW and HMW (included MMW) in the street dust were accounted for 38.3% and 61.7% of the total PAHs, respectively. Two components are founded in the PCA with HMW accounted for 75.8% of the total PAHs, and PAHs LMW contributed 24.2% of the total PAHs. Ratios results in nutshell indicated the predominance of pyrogenic source for sixteen PAHs. This suggested by possible sources such as the emission from vehicles, regular gas and fuel combustion activities, as well as coal and wood, were the major cause of 16 principal PAHs in SD samples in all three land-use in Babylon governorate. Results from ILCR model stated that total cancer risk for both targeted individuals exposed to SD in all land-use is more than 10-4 that is referred to increase potential health risk. The PAHs contamination in Babylon governorate needs urgently to be addressed on priority. Moreover, this work is beneficial for Babylon governorate to utilize it as a benchmark for future research

Ecological and human health risk assessment of polycyclic aromatic hydrocarbons (PAH) in Tigris river near the oil refineries in Iraq

Recent Iraqi battles against ISIS in 2014 and 2015 resulted in the destruction or severe damage to several refineries' infrastructure. This, along with other factors, has led to the release and accumulation of a wide range of hazardous chemicals into the environment, for instance, polycyclic aromatic hydrocarbons (PAH). Thus, for the first time, a comprehensive 16 PAHs measurements campaign over the course of six months near the oil refineries along the Tigris River and its estuaries was investigated. The 16 PAHs concentrations in surface water and the sediments for the following oil refineries: Baiji, Kirkuk, Al-Siniyah, Qayyarah, Al-Kasak, Daura, South Refineries Company, and Maysan were examined. The overall findings indicated that the 16 PAHs concentrations ranged from 567.8 to 3750.7 ng/L for water and 5619.2–12795.0 ng/g for sediment. Water samples in South Refineries Company recorded the highest PAH concentrations while Baiji oil refinery registered the highest PAH concentrations in the sediment samples. The percentages of high molecular weight PAH (5–6 rings) in water and sediment samples were the highest, ranging from 49.41% to 81.67% and from 39.06% to 89.39% of total PAH for water and sediment, respectively. The majority of 16 PAHs measured in water and sediment samples of the Tigris River were derived from pyrogenic sources. Based on sediment quality guidelines (SQGs), most sites showed a possible effect range with occasional biological effects of most of the PAH concentrations in all sediments’ samples. The calculated incremental lifetime cancer risk (ILCR) value was high risk with adverse health effects, including cancer

Removal of emerging pollutants from water using enzyme-immobilized activated carbon from coconut shell

This work reports the removal of diclofenac, amoxicillin, carbamazepine, and ciprofloxacin by utilizing three commercially available granular activated carbons (GACs) (Activated carbon, Silcarbon, and Donau) loaded with laccase. Adsorption was used to successfully immobilize laccase on the GACs, as revealed by scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDX) and Fourier transform infrared spectroscopy (FTIR). In the three types of GACs tested, pH 5, 30 °C, and 2 mg mL−1 laccase content were found to be the optimum immobilization parameters. Laccase immobilization yields of 65.2%, 63.1%, and 62.9% were achieved with activated carbon, Silcarbon, and Donau respectively. The adsorption behaviors of the pharmaceuticals onto the tested activated carbons are best described as a spontaneous endothermic process that follows Langmuir isotherm and first-order kinetics. The reusability of the immobilized enzyme was evaluated using 2, 2′-azino-bis 3-ethylbenzothiazole-6-sulphonic acid (ABTS) as a substrate within six cycles for all adsorbents. In 120 mins, nearly a complete removal of the pharmaceutical compounds (50 mg L−1) was obtained in the case of activated carbon type and more than 90% for other adsorbent types when synergistic adsorption and enzymatic degradation were applied. With adsorption alone, 74% removal was obtained with activated carbon and < 56% for other adsorbents. The finding of this study suggests that biochar produced from coconut shell (same as the one used in this study) can effectively be used as a substrate and adsorbent for pharmaceutical removal. This enzymatic physical removal system has the potential to be applied on a large-scale

Removal of Pharmaceuticals from Water Using Laccase Immobilized on Orange Peels Waste-Derived Activated Carbon

The ongoing discharge of containments into the environment has raised concerns about the potential harm they pose to various organisms. In the framework of eliminating pharmaceutical chemicals from aqueous solutions, enzymatic degradation by laccase is an environmentally friendly option. In this investigation, laccase immobilized on biochar derived from agricultural waste (orange peels, OPs) was used for the first time to remove carbamazepine and diclofenac from aqueous media. Different characterizations, such as Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), X-Ray diffraction (XRD), specific surface area (SBET), Boehm titration, proximate and ultimate analysis, as well as the point of zero-charge (pHPZC) analysis, were used in this study. The immobilization of laccase results in enhanced stability with respect to storage, temperature, and pH compared to laccase in its free form. The findings showed that the ideal conditions for immobilization were a pH of 4, a temperature of 30 °C, and a laccase concentration of 4.5 mg/mL. These parameters led to an immobilization yield of 63.40%. The stability of laccase immobilized on biochar derived from orange peels (LMOPs) was assessed over a period of 60 days, during which they preserved 60.2% and 47.3% of their initial activities when stored at temperatures of 25 °C and 4 °C, respectively. In contrast, free laccase exhibited lower stability, with only 33.6% and 15.4% of their initial activities maintained under the same storage conditions. Finally, the use of immobilized laccase proved to be effective in eliminating these pollutants in up to five cycles. Upon comparing the two systems, namely LMOPs and modified orange peels (MOPs), it becomes apparent that LMOPs exhibit an estimated 20% improvement in removal efficiency. These results affirmed the viability of activated carbon derived from OPs as a cost-effective option for immobilizing laccase. This approach could potentially be further scaled up to effectively eliminate organic pollutants from water sources

Personal exposure and inhalation doses to PM1 and PM2.5 pollution in Iraq: An examination of four transport modes

Particulate matter (PM) is a major indicator of urban air quality deterioration due to its impact on human health, atmospheric visibility and climate change. However, sufficient data on personal exposure to air pollution is still rare or unavailable in developing countries such as Iraq. Thus, this paper investigated the personal exposure and inhalation doses of PM1 and PM2.5 in Al-Hillah city, Iraq, for four common motorized transportation modes, namely open windows car, closed window car, bus, and motorbike. A portable monitoring device was used to collect the data during morning and afternoon hours in two main streets in the city. A t-test examination of the obtained results showed that the mean exposure concentration for both PM2.5 and PM1 were significantly different in the two streets form most of the transportation modes. The difference in the means of the measured PM1 and PM2.5 in the morning and afternoon trips were statistically significant for all the transportation modes except for bus in 60 street. This highlights the special and temporal variation of air pollution in the city. This is largely due the deteriorated infrastructure and lack of control policies in the city. Overall, PM2.5 and PM1 measured exposure concentrations were higher in the morning trips than in the afternoon ones. Regardless of the time or place of measurements, closed windows cars always had the lowest exposure concentrations to PM1 and PM2.5. The alarming observation in this study was the high levels of PM1 and PM2.5 that exceeded the recommended WHO limits, and were higher than the reported concentrations in the world bank database. The study findings present preliminary data on personal exposure concentrations and inhalation doses for travelers in Al-Hillah city, which can be utilized for global studies of air contamination in countries in similar situations as Iraq and for developing local control strategies

Ketoprofen and aspirin removal by laccase immobilized on date stones

In recent years, enzymatic remediation/biocatalysis has gained prominence for the bioremediation of recalcitrant chemicals. Laccase is one of the commonly investigated enzymes for bioremediation applications. There is a growing interest in immobilizing this enzyme onto adsorbents for achieving high pollutant removal through simultaneous adsorption and biodegradation. Due to the influence of the biomolecule-support interface on laccase activity and stability, it is crucial to functionalize the solid carrier prior to immobilization. Date stones (PDS),as an eco-friendly, low-cost, and effective natural adsorbent, was utilized as a carrier for laccase (fungus Trametes Versicolor). After activating PDS through chemical treatments, the surface area increased by thirty-six-fold, and carbonyl groups became more prominent. Batch experiments were carried out for ketoprofen and aspirin biodegradation in aqueous solutions. After six cycles, the laccase maintained 54% of its original activity confirmed by oxidation tests of 2,2′-azino-bis (3 ethylbenzothiazoline-6-sulphonic acid) (ABTS). In addition, the storage, pH, and thermal stability of immobilized laccase on functionalized date stone (LFPDS) were found to be superior to that of free laccase, demonstrating its potential for ongoing applications. In the aqueous batch mode, this immobilized laccase system was used to degrade 25 mg L-1 of ketoprofen and aspirin, resulting in almost complete removal within 4 h of treatment. This study reveals that agricultural wastes such as date stone can successfully be valorized through simple activation techniques, and the final product can be used as an adsorbent and substrate for immobilization enzyme. The high efficiency of the LFPDS in removing ketoprofen and aspirin highlights the potential of this technology for removing pharmaceuticals and merits its continued development

Polycyclic aromatic hydrocarbons in the surface water and sediment along Euphrates River system: Occurrence, sources, ecological and health risk assessment

This study presented for the first time a comprehensive measurement campaign of 16 PAHs along the Euphrates River for five months, in both water and sediment samples. Our study revealed that the PAHs contamination increased along the flow direction due to the increasing non-point pollution and the return flows of agriculture. The 5–6 rings PAHs were dominant in water and sediment samples with an average of 42 % and 50 %, respectively. The diagnostic ratios of PAHs suggest that the pollution of these compounds originated mainly from petroleum product combustions. The carcinogenic PAHs formed 46 % and 55 % of the total measured compounds in water and sediment samples, respectively, which highlights potential ecological and human health risks. Based on sediment quality guidelines (SQGs), most sites exhibit an effect range between low and medium. The calculated incremental lifetime cancer risk (ILCR) for adult and children were in the 10−2–10−3 range, which is 3–6-fold higher than what was reported in the literature. These observations call for urgent attention from environmental authorities of countries sharing this key water source in Western Asia