PM2.5 characterization of primary and secondary organic aerosols in two urban-industrial areas in the East Mediterranean

Primary and secondary organic aerosols in PM_2.5 were investigated over a one-year campaign at Zouk Mikael and Fiaa, Lebanon. The n-alkanes concentrations were quite similar at both sites (26-29 ng/m³) and mainly explained by anthropogenic emissions rather than natural ones. The concentrations of total Polycyclic Aromatic Hydrocarbons (PAHs) were nearly three times higher at Zouk Mikael (2.56 ng/m³) compared to Fiaa (0.95 ng/m³), especially for indeno[1,2,3-c,d]pyrene linked to the presence of the power plant. A characteristic indeno[1,2,3-c,d]pyrene/(indeno[1,2,3-c,d]pyrene + benzo[g,h,i]perylene) ratio in the range 0.8-1.0 was determined for heavy fuel oil combustion from the power plant. Fatty acids and hopanes were also investigated and were assigned to cooking activities and vehicular emissions respectively. Phthalates were identified for the first time in Lebanon with high concentrations at Zouk and Fiaa (106.88 and 97.68 ng/m³ respectively). Moreover, the biogenic secondary aerosols revealed higher concentrations in summer. The total terpene concentration varied between 131 ng/m³ at Zouk Mikael in winter to 469 ng/m³ at Fiaa in summer. Additionnally, the concentrations of the dicarboxylic acids especially for adipic and phthalic acids were more influenced by anthropogenic sources.The analysis of molecular markers and diagnostic ratios indicated that the sites were strongly affected by anthropogenic sources such as waste open burning, diesel private generators, cooking activities, road transport, power plant, and industrial emissions. Moreover, results showed different pattern during winter and summer seasons. Whereas, higher concentrations of biogenic markers were clearly encountered during the summer period.     

Treatment of an explosives plume in groundwater using an organic mulch biowall

A field demonstration of a mulch permeable reactive barrier (PRB), or “biowall,” as an in situ treatment technology for explosives in groundwater is summarized. Organic mulch consists of insoluble carbon biopolymers that are enzymatically hydrolyzed during decomposition to release aqueous total organic carbon (TOC). The released TOC is then available for microorganisms to use as an electron donor to transform electrophilic contaminants via reductive pathways. A 100‐foot‐long and 2‐foot‐thick mulch biowall was installed at the Pueblo Chemical Army Depot in Colorado to treat a shallow groundwater plume containing hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX). To discourage groundwater flow bypassing around and under the biowall in this highly permeable formation, a hydraulic control was installed and the PRB was keyed into the bedrock. Technology performance was monitored using a monitoring well network to establish the development and extent of the downgradient treatment zone. Performance objectives of the field demonstration were: (1) greater than 90 percent removal of RDX across the PRB and the treatment zone; (2) an RDX concentration of less than 0.55 μg/L in the treatment zone; and (3) cumulative toxic intermediate concentration (nitroso intermediates of RDX, MNX, DNX, and TNX) of less than 20 percent of the upgradient RDX concentration. All performance objectives were met within seven months after installation once the system reached a pseudo‐steady state. By this point, a sustained reducing/treatment zone had been created downgradient of the mulch PRB that showed greater than 93 percent RDX removal, RDX concentrations less than 0.55 μg/L, and no accumulation of toxic intermediates. The mulch biowall implemented during this demonstration was successful at meeting performance objectives while addressing the majority of potential concerns of the technology. © 2009 Wiley Periodicals, Inc.     

Highly efficient degradation of metronidazole drug using CaFe2O4/PNA nanohybrids as metal-organic catalysts under microwave irradiation

Environmental Science and Pollution Research - Catalytic degradation based on microwave irradiation is an emerging technique which promises prompt and efficient catalytic degradation of organic...     

Environmental factors affecting the frequency of road traffic accidents: a case study of sub-urban area of Pakistan

Road traffic accidents (RTAs) are among the life-threatening issues facing rural as well as sub-/urban communities. Several factors contribute to RTAs ranging from human to technical and natural/environmental impacts. Anthropogenic air pollution and corresponding environmental factors also increase the probability of RTAs. Current study reports the relationship of the weather conditions to RTAs. The study establishes the relevancy of different weather conditions like rainfall, temperature, fog, and wind storm with the incidences of RTAs in rural and urban settings of Vehari, Punjab—Pakistan. The results of the study showed that rainfall, severe coldness, fog, and heat conditions were directly related with the occurrence of RTAs. The percentage of RTAs which occurred due to fog, rainfall, temperature, and other weather-related factors was 34, 25, 21, and 20%, respectively. The age of the driver significantly correlated (R²?=?0.60) with RTAs; the drivers in the age group 40–60 years caused the least RTAs during their drive. Since the smaller vehicles were involved in maximum RTAs, it relates negatively (R²?=?0.82) to vehicles power. Among different vehicles motor bikes were involved in most (42%) of the reported RTAs. Therefore, during severe weather conditions, vehicles with smaller size and young drivers must be dealt with carefully while interacting (crossing, overtaking, and maneuvering) on the roads regardless of rural or urban conditions. Factors including civic sense, traffic education, vehicle size, drivers’ maturity, road conditions, and environmental impacts may be considered while designing traffic rules and traffic aware campaigns specific for developing countries such as Pakistan.

     

Nutrient concentrations within and below root zones from applied chicken manure in selected Hawaiian soils

The objective of this study was to evaluate the effects of chicken manure (CM) application rates on nutrient concentrations within and below the root zone of sweet corn (Zea mays L. subsp. mays) under Hawaiian conditions. The research was conducted in leeward (Poamoho) and windward (Waimanalo) areas of Oahu, Hawaii, where contrasts exist in both climatic and soil conditions. Suction cup were used to collect soil solutions from 30 and 60 cm depths. Soil solutions were collected six times during the growing season at each location and analyzed for different nutrients (N, P, K, Ca, Mg, Na, Fe, Mn, Zn, and Cu), nitrate-nitrogen (NO₃–N), ammonium-nitrogen (NH₄–N), electrical conductivity (EC), and pH. Analysis showed that CM rates significantly affected the concentration of macro-nutrients below the root zone at Poamoho and within the root zone at Waimanalo. In general, nutrient concentration increased with the increasing rates of CM application. There was a significant effect of CM on micro-nutrients except below the root zone at Poamoho. CM significantly affected NO₃–N concentration within the root zone for 15, 60 days after planting (DAP) at Poamoho, and 16, 28 DAP at Waimanalo. The effect was also significant on total nitrogen (N) concentration in the root zone across the two growing seasons at Waimanalo. There was a highly significant correlation between total N and NO₃–N, and EC within and below the root zone.     

Bacteriological quality assessment of drinking water available at the flood affected areas of Peshawar

Monsoon flooding occurred in the main areas of the Khyber Pakhtunkhwa, Punjab, and Balochistan as well as parts of Gilgit Baltistan of Pakistan and Azad Jammu Kashmir in July 2010. Water-borne diseases such as cholera, enteric fever, and dysentery were common among the inhabitants of flood-affected areas which were selected for sample collection. In the present study, 10 sites in District Peshawar were selected and drinking water samples collected. These samples were analyzed for the total plate count (TPC), total coliform bacteria (TCB), total fecal coliform bacteria (TFCB), Escherichia coli (EC), Pseudomonas aeruginosa (PA), Vibrio cholerae (VB), Salmonella Shigella, and Staphylococcus aureus. The TPC ranged from 8 × 10¹ to 7 × 10⁴ CFU/ml. The TCB ranged from <1.1 to 280 MPN/100 ml. Twenty percent of the samples were contaminated with TFCB, EC, Salmonella, Shigella, and Staphylococcus aureus, while only one sample contaminated with PA. Forty percent of the samples were contaminated with VB. The surface and well water was greatly contaminated by flooding and major improvements on priority basis are essential.     

Hybrid-based Bayesian algorithm and hydrologic indices for flash flood vulnerability assessment in coastal regions: machine learning,risk prediction,and environmental impact

Environmental Science and Pollution Research - Natural hazards and severe weather events are a matter of serious threat to humans, economic activities, and the environment. Flash floods are one of...