Qasem M. Jaradat

Chemical Composition of Urban Wet Deposition in Amman, Jordan

Precipitation events were collected during the period from October 1996 to April 1997 from two sites in the city of Amman, Jordan. The samples were analyzed for major cations (Na+, K+, Ca2+, Mg2+ and NH4+), major anions (F-, Cl-, NO3- and SO42-), in addition to heavy metals (Cu2+, Cd2+, Zn2+, and Pb2+). High levels of Ca2+ and SO42- were observed. The results were comparable with some regional values and they indicate that about 58% of Na+ and Cl- are of marine origin, while Ca2+, K+ and a large fraction of SO42- are of soil dust origin. Heavy metals were detectable in most of the samples, zinc showed the highest concentrations. Significant correlation was obtained between zinc and lead, which may indicate automobile emission source.

Lead and Cadmium Contamination in Roadside Soils in Irbid City, Jordan: A Case Study

This study evaluates the amount and distribution of Pb and Cd in roadside soils adjacent to two main roads in Irbid, Jordan, from October 2001 to July 2002. A total of 260 samples were collected from Irbid-Howara Street and Yarmouk University Street. Lead and Cd content were measured using Graphite Furnace Atomic Absorption Spectrometry. The environmental significance of this study is discussed in terms of the influence of traffic density on Pb and Cd concentrations in roadside soils, and enrichment factors were calculated to evaluate the degree of pollution. The accuracy of the results obtained has been examined and two standard reference materials, CRM 142 R (soil) and SRM 2709 (soil), were analyzed to confirm the accuracy of the results. The precision of the measurements was assessed in terms of relative standard deviation (RSD) using five replicate analyses of samples collected from the roadside sites. RSD values for Pb and Cd were found to be less than 6%. The overall Pb concentration in roadside soil samples was 325 and 431 μg g−1 for Pb and 1.142 and 1.135 μg g−1 for Cd in Yarmouk University Street and Irbid-Houwa Street, respectively. Results indicated that levels of Pb and Cd were decreasing as the distance from the road increases. Enrichment factor results were 655 and 826 for Pb, and 252 and 237 for Cd in Yarmouk University Street and Irbid-Houwa Street, respectively.

Heavy Metal Contamination of Soil, Plant and Air of Scrapyard of Discarded Vehicles at Zarqa City, Jordan

Ninety soil samples, forty plant samples (Anabasis articulata), and twenty air samples were collected from the scrap yard of discarded vehicles near Zarqa city, Jordan. These samples were analyzed for heavy metals: Cd, Pb, Zn, Cu, Mn, Al, and Fe. Longitudinal and vertical profiles of soil samples were studied. Generally, the levels of all heavy metals studied in the scrap yard area were found to be higher than those of the control samples. The levels of heavy metals decreased with depth until reaching a constant value at 9 cm depth. The levels of heavy metals also decreased at distances farther away from the scrap yard area. A significant difference in heavy metal concentrations was found between washed and unwashed plant samples. On the other hand, no significant differences have been found between plant samples from inside and outside the scrap yard area. Air samples showed wide variations in heavy metal levels among the sampling sites. The enrichment factors for non-crustal elements such as Pb, Cd, Cu, and Zn, in both soil and particulate matter, were found to be more than 10, indicating anthropogenic sources such as dust, rust, and exhaust emissions from the scrap yard area, whereas the crustal elements such as Fe and Mn showed enrichment factors of less than 10.

The spatial distribution of Pb, Cd, Zn, and Cu in agricultural roadside soils.

The primary objective of this study was to characterize the roadside agricultural soil samples from the Bani Kenanah District, North Jordan, in terms of heavy metal concentrations and soil characteristics. Samples were collected from different sites, at different depths, and at variable distances from the road starting from June 2004 to December 2004. The concentrations of heavy metals were measured by atomic absorption spectrophotometry. Samples were separated into seven physical fractions <90, 90–106, 106–125, 125–200, 200–250, 250–1000, and 1000–2000 μm to investigate the relationship between metal content and size fraction. The overall trend of heavy metal variations with particle size was that as sizes increase, concentrations decrease. The Pb, Zn, Cd and Cu profiles in soil demonstrated high concentrations in the top layer, 0–4 cm, but fall rapidly with increasing soil depth.

Distribution of Heavy Metals in Some Tree Leaves along the Main Road in an Agricultural Area

Four types of tree leaves were investigated (olive, fig, oak, and carob). The tree leaf samples, washed and unwashed, were analyzed for lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) by atomic absorption spectrophotometry. Variable levels were found in these plants. In addition, all heavy‐metal concentrations of the samples were significantly higher than their counterparts of the control, indicating heavy‐metal pollution was taking place. Very high correlations were found between heavy metals in the same plant, between different plants, and between plants and soil, indicating common sources of heavy metals, possibly soil and soil pollution sources such as traffic. The accuracy of the analytical method used for heavy metals was checked by analysis of standard reference materials, rye grass (CRM 281) and spinach leaf (SRM 1570a). The percentages of recovery of both reference materials for Cd, Cu, Pb, and Zn were better than 93%.

Water-soluble species and heavy metal contamination of the petroleum refinary area, Jordan

The levels of lead, cadmium, copper, zinc, aluminum, chromium, and iron in street dust, soil, and plants in the Jordanian petroleum refinery were determined using flame and graphite-furnace atomic absorption spectrophotometry. Major cations (Li+, Na+, NH4+, K+, Mg2+, and Ca2+) and anions (F-, Cl-, NO3-, SO4(2-), and Br-) were also determined using suppression mode ion chromatography. Generally, higher levels of the heavy metals studied were found in street dust samples than in soil samples. On the other hand, except Cl-, and Li+ ions, other anions and cations showed higher concentrations in soil than in street dust samples. For plant samples, unwashed samples showed higher levels of heavy metals than their washed counterparts, indicating that dust fall is a source of heavy metal contamination.

Heavy metals in fish from the Red Sea, Arabian Sea, and Indian Ocean: effect of origin, fish species and size and correlation among the metals.

This study determined the levels of As, Cu, Pb, and Cd in fish from Red Sea, Arabian Sea, and Indian Ocean by graphite furnace atomic absorption spectrophotometry. Metal levels were compared with international standards. The levels among fish types and origin, the relationship among metals, and the correlation between the levels and fish size were statistically tested. Fish type and origin significantly affected the levels. None of the fish contained As, Cu, and Pb above the FAO and EU codes. However, Cd exceeded the Jordanian, FAO, and EC codes from the three origins. As and Cd positively correlated with each other in Arabian Sea fish. As and Pb correlated negatively, but Cu and Cd did not correlate with fish size. This study indicates that Cd is common in fish from the three origins regardless the fish size. This warrants continuous monitoring for heavy metals, especially Cd, in internationally traded fish.

Pr(III) luminescence enhancement by chelation in solution and in sol-gel glass.

Due to the weak emission of lanthanide ions in solution, it is common practice to form complexes of the lanthanide ions with organic ligands that strongly absorbs light and transfers the energy to the lanthanide ion center via the antenna effect. The organic ligands 2-6-pyridinedicarboxylate (L1) and the polytonic diazine (N-N) ligand L2 (C22H16N12O2) were used to synthesize two Pr(III) complexes, namely: Pr-L1 (Na3[Pr(C7H3NO4)3]) and Pr-L2. The prepared complexes were further encapsulated in an optically transparent sol-gel glass. The synthesized ligands and complexes were characterized by FTIR and (1)H NMR. Room temperature luminescence of Pr-L1 and Pr-L2 complexes in solution and in sol-gel glass were investigated using a spectrofluorometer. Excitation at the maximum absorption wavelength of the ligands (280nm) resulted in the typical visible luminescence (centered at around 600nm) resulting from the (1)D2→(3)H4 transition of the Pr(III) ion, which contributes to the efficient energy transfer from the absorbing ligand L1 to the chelated Pr(III) ion (an antenna effect) while the Pr(III) luminescence is not efficiently sensitized by ligand L2. The obtained emission spectra indicated that the excitation energy level for the central Pr(III) is in a slightly lower location than ligand L1 excitation triplet (T1) level and can accept the energy transfer from T1 efficiently.

Heavy Metal Content and Health Risk of Potato and Corn Chips Being Sold in Jordanian Market

This study was carried out to investigate the heavy metal contaminants (cadmium, lead, copper, zinc, manganese and iron) found in potato and corn chips being sold in Jordanian market, and to estimate their health risk on consumers. The reason behind this study was that potato and corn chips are widely consumed by most children over the world. Atomic Absorption Spectrometry was used to measure the levels of metals after wet digestion, then the dietary intake of each heavy metal was estimated based on means of chips intake by Jordanian children. Also, the level of risk found in this study was evaluated with respect to the value of Minimal Risk Level. From this study, the level of copper, zinc, iron and manganese were below the recommended tolerable levels proposed by Minimal Risk Level. In Contrast, there are some risks in some kinds of chips because they have high levels of cadmium and lead. The levels were compared with those reported for similar cases from some other parts of the world. Moreover, the study shows also that the domestic-made chips have lower concentration of heavy metals than those imported from other countries. In addition, the concentration of heavy metals in the chips available in the local markets increases as the price of these chips increases except for iron. In general, the levels of heavy metals in potato chips samples were higher than those in corn chips. The average concentration of heavy metals in potato chips was found as follows: 10.32, 2.25, 3.15, 6.57, 7.84 and 0.25 mg/Kg for Fe, Cu, Mn, Pb, Zn and Cd, respectively, whereas that in corn chips was 6.42, 0.54, 1.33, 6.79, 5.67 and 0.21 mg/Kg for iron, copper, manganese, lead, zinc and cadmium, respectively.

Average Particle Size Ratios and Chemical Speciation of Copper and Zinc in Road-Dust Samples

Road-dust samples were taken from areas of high traffic flows in Irbid City; Jordan. A series of <90, 90-<106, 106-<125, 125-<250, 250-<1000 and 1000-< 2000 µm of road-dust particle size fractions were investigated throughout to evaluate the ratio between metal content in each particle size fraction and total metal content. Atomic absorption spectrometry technique was used throughout. Sequential procedure was used for chemical speciation in road dust samples of <90 µm. This procedure permits a reproducible evaluation of the partitioning of Cu and Zn among the various chemical forms in which they are present in street dust. Two reference standard materials BCR-CRM 142R and NIST-SRM 2709 were tested to validate the propo sed method. Results show that there was no significant difference between the measured values for Cu and Zn and their certified values with RSD of less than 5%.