Adnan M. Massadeh

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.

Removal of lead and cadmium by halophilic bacteria isolated from the Dead Sea shore, Jordan.

Ten Gram-positive and Gram-negative bacterial cultures were recovered from nine water, mud, and soil samples from the Dead Sea shore at Suwaymah. They were able to grow at 10% NaCl and at 45°C. Bacterial cultures 6 and 8 were able to grow in nutrient media supplemented with 2250 ppm of Pb. Bacterial cultures 1, 3–6, 9, and 10 were able to grow in nutrient medium supplemented with 1000 ppm of Cd. Atomic absorption spectrometry was used to estimate the absorbed Pb and Cd by bacterial cultures from 5-, 25-, 100-, and 500-ppm stock solutions of both elements. After 2 wk, the results showed that the maximum absorption for Pb was achieved by culture 6 on the following percentages: 79.8%, 70,48%, 89.48%, and 83.39%, respectively. The maximum absorption of the same concentration of Cd was achieved by culture 9 with the following percentages: 69.2%, 32.24%, 44.98%, and 60.0%, respectively. After 3 wk of incubation, the estimated absorption of both heavy metals was achieved by the same cultures (6 and 9), respectively, in the following percentages: 86.8%, 76.72%, 96.25%, and 96.0% for Pb and 82.60%, 93.2%, 92.74%, and 89.79% for Cd. The accumulation of the absorbed metals was found to be maximum in the protoplast of all the cultures. The accumulation at the cell wall was maximum in culture 2, and between the cell wall and the plasma membrane, it was maximum in cultures 2 and 8 for Pb and Cd, respectively.

Uptake of Zinc and Copper by Halophilic Bacteria Isolated from the Dead Sea Shore, Jordan

Ten Gram-positive and gram-negative bacterial cultures were recovered from nine water, mud, and soil samples collected from the Dead Sea shore at Suwaymah. All bacterial cultures were able to grow at 10% NaCl and at 45°C. They were able to grow in nutrient media supplemented with 1250 ppm of Zn. Most of them, except cultures 2 and 8, were able to grow in nutrient medium supplemented with 1000 ppm of Cu. After 2 wk of incubation of these 10 cultures at different concentrations (5, 25, 100, and 500 ppm), stock solutions of both Zn and Cu elements, the maximum absorption using atomic absorption spectrometry for Zn was achieved by culture 7 at 11.2%, 1.0%, 38.4%, and 84.54%, respectively, from the previous stock solutions, whereas the maximum absorption of the same concentration of Cu was achieved by culture 3 at 6.2%, 55.56%, 85.66%, and 90.82%, respectively, of the different concentrations. After 3 wk of incubation, the estimated absorption for Zn was achieved by cultures 2, 9, and 10 at 19.2%, 16.68%, 42.92%, and 76.5%, 18.2%, 21.56%, 32.22%, and 77.43%, and 20.8%, 23.52%, 32.22%, and 82.84% of the previous stocks. The maximum absorption of the same concentration of Cu was achieved by culture 3 at 32.6%, 49.88%, 90.44%, and 91.86%, respectively. The accumulation of the absorbed metals was found to be maximum in the protoplast of all cultures. The accumulation at the cell wall was maximum for cultures 2 and 6 for Zn and Cu, respectively, and between the cell wall and the plasma membrane, it was maximum for cultures 2 and 8 for Zn and Cu, respectively.

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.

Lead, cadmium, copper, zinc, iron, and calcium in human hair as a function of gender, age, smoking, and hair dyeing

Hair samples were collected randomly from 110 subjects (55 male and 55 female) ranging in age from (<15–60) years. Each subject was asked to complete a personal questionnaire describing his/her sex, age, general health, smoking, use of hair dyes, occupational area, and living habits. Concentrations of Pb, Cd, Cu, Zn, Fe, and Ca in human hair samples were evaluated using atomic absorption spectrometry. Results indicated that concentrations of Pb, Cd, Cu, and Zn in the hair of smokers were higher than those in the hair of non-smokers, whereas, Fe and Ca concentrations in hair of smokers were lower than those in hair of non-smokers. Moreover, the concentrations of these elements are higher in dyed hair compared with undyed hair.

Analysis of cadmium and lead: their immunosuppressive effects and distribution in various organs of mice.

Chronic exposure (3.5 mo) of mice to cadmium (Cd), lead (Pb), or a cadmium-lead mixture at a concentration of 1 ppm in drinking water induced a highly significant inhibition of antibody response to human serum. The highest immunosuppression (84.4%) was induced by the Cd-Pb mixture, whereas Cd caused the lowest immunosuppression (53.6%). The body burden of Cd and Pb in various organs was investigated in the four groups of mice by atomic absorption spectrometry. The highest level of Cd was found in the kidney of the Cd-treated group, and the highest level of Pb was found in the liver of the Pb- and Cd-Pb-treated groups. It is concluded that when mice are exposed concurrently to Cd and Pb, they develop synergistic immunsuppression. Analysis of Cd levels using atomic absorption spectrometry revealed that it was distributed in the following order: kidney>liver>spleen>heart, whereas Pb was distributed in the following order: liver>kidney>spleen>heart.

Analysis of cadmium and lead in mice organs : Effect of nigella sativa L. (Black Cumin) on the distribution and immunosuppressive effect of cadmium-lead mixture in mice

Analysis and distribution of Pb and Cd in different mice organs, including the liver, kidney, spleen, heart, and blood, were evaluated before and after treatment with different aqueous concentrations of Nigella sativa (1.25–10.0 mg/L). Atomic absorption spectrometry was used for analysis of Pb and Cd in these organs. Results indicated that the Pb in the unexposed group of mice without treatment with N. sativa (black cumin) was in the following order: liver>heart>spleen>kidney, and the distribution of Pb in various organs of the unexposed group was not affected significantly by N. sativa. Moreover, results of mice exposed for Pb show that the Pb concentrations in different organs were reduced significantly (p<0.05) by 72.9%, 63.4%, 72.3%, 66.7%, and 39.5% at a dose of 10 mg/L of N. sativa for the liver, kidney, heart, spleen, and blood, respectively. Furthermore, the distribution of Cd in the unexposed Cd group of mice without treatment with N. sativa was in the following order: kidney>heart>spleen>liver. Nigella sativa at 10 mg/L reduced Cd levels in mice exposed to Cd by 75.5%, 83.3%, 47.0%, 95.3%, and 100% in the liver, kidney, heart, spleen, and blood, respectively, whereas blood Cd concentrations were lowered to below the detection limit of 0.05 μg/L.A 28-d exposure of mice to a Cd−Pb mixture at a concentration of 1 ppm in drinking water induced a highly significant inhibition (p<0.0001) of antibody response to human serum (80.5%). The suppressed immune responses in mice pretreated with the Cd−Pb mixture were reversed by 43.1% and 38.9% in the presence of 1.25 and 2.5 mg/mL of N. sativa, respectively, whereas higher concentrations (5–10 mg/mL) of N. sativa increased the immunosuppression significantly. Nigella sativa at 1.25–10 mg/mL did not induce any significant modulation of the antibody response in unexposed mice.

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%.

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.

Chemical Speciation of Lead and Cadmium in Different Size Fractions of Dust Samples from Two Busy Roads in Irbid City, Jordan

Concentrations of Pb and Cd in different size fractions in road dust samples taken from areas of high traffic flows in two streets in Irbid City, Jordan, have been measured using graphite furnace atomic absorption spectrometry (GFAAS). A series of road dust particles in the following size ranges, < 90, 90–106, 106–125, 125–250, 250–1000 and 1000-2000 μ m, were investigated to evaluate the ratio between metal content in each fraction of particle size and total metal content. Results show most of the highest levels were found in the small particle sizes. Sequential extraction procedure was used for chemical speciation in road dust samples of < 90 μ m. Two standard reference materials, CRM142R and SRM 2709, were analyzed to assess the accuracy and the reliability of the proposed method, and the precision of the results was expressed by relative standard deviation (rsd < 6%).