Simultaneous determination of tramadol in earwax and urine samples: effects of age, duration time and sex.

Background: This study aims to determine the concentrations of tramadol in earwax (µg/g) and urine (µg/ml) samples taken from postoperative patients, to evaluate the sensitivity of earwax (cerumen) as an alternative analyte and compare it with the findings in urine samples. Results: The results indicated that tramadol concentrations in earwax samples were averaged 45.08 µg/g (range: 13.5-107.7 µg/g), whereas tramadol concentrations in urine samples were averaged 4.97 µg/ml (range: 1.57-10.11 µg/ml). There were significant differences when comparing age groups, duration and sex between earwax and urine samples (p < 0.05). Conclusion: Despite the significant differences between earwax and urine samples, earwax can be used as a bioindicator of tramadol detection.

Assessing the Influence of Salvia triloba on Memory Deficit Caused by Sleep Deprivation in the Context of Oxidative Stress.

BACKGROUND: Learning and memory deficit has been reported to be correlated to oxidative mutilation in the hippocampus. Moreover, sleep deprivation (SD) mitigates memory via distressing oxidative stress balance. In the current report, the prospective neuroprotective role of oral sage (Salvia triloba) extract on cognitive impairment induced by chronic SD was investigated. METHODS: The SD was induced in adult male Wistar rats employing a modified multiple platform (8 h/day; for six weeks). Simultaneously, S. triloba extract (375 mg/kg, orally) was administered for six weeks. Thereafter, the Radial Arm Water Maze test was utilized to evaluate spatial learning and memory. Moreover, activities of different hippocampal antioxidant parameters: glutathione peroxidase (GPx), oxidized glutathione (GSSG), reduced glutathione (GSH), catalase, superoxide dismutase (SOD), and the thiobarbituric acid reactive substance (TBARS) were measured in rats' hippocampus. Moreover, the level of brain derived neurotrophic factor (BDNF) was assessed. RESULTS: Current results illustrate that chronic SD significantly compromised both memories, shortand long-term, while sage extract inhibited these consequences. Moreover, sage extract remarkably stabilized the antioxidant enzyme levels, which were decreased by SD, such as: SOD, catalase, and GPx (P < 0.05), and remarkably augmented the GSH/GSSG ratio in SD rats (P < 0.05). However, no substantial alterations of GSH, TBARS or BDNF levels (P > 0.05) were seen with sage extract administration. CONCLUSION: Chronic treatment with sage extract (S. Triloba) precluded SD-induced memory impairment by regularizing antioxidant parameters levels in rats' hippocampus.

Evaluating the effect of selenium on spatial memory impairment induced by sleep deprivation.

Sleep deprivation (SD) impairs memory due to disturbing oxidative stress parameters. Selenium is a main component of several antioxidant enzymes and provides a neuroprotective effect. The present study aimed to investigate the potential neuroprotective effect of chronic selenium administration on cognitive impairments induced by chronic SD. Adult male Wister rats were randomly assigned into five groups (n = 12/group). The SD was induced in rats using modified multiple platform model. Selenium (6 µg/kg of animal's body weight) was administered to rats via oral gavage for 6 weeks. The spatial learning and memory were assessed using the radial arm water maze (RAWM). Moreover, we measured the levels of reduced glutathione (GSH), oxidized glutathione (GSSG) and GSH/GSSG, catalase, glutathione peroxidase (GPx), superoxide dismutase (SOD), thiobarbituric acid reactive substances (TBARS) and brain derived neurotrophic factor (BDNF) in the hippocampus. The results indicate that short- and long-term memory were impaired by chronic sleep deprivation (P < 0.05), while selenium administration prevented this effect. Moreover, selenium normalized antioxidants activities which were reduced by SD such as: catalase (P < 0.05), and SOD (P < 0.05), and significantly enhanced the ratio of GSH/GSSG in sleep-deprived rats (P < 0.05), without significant alteration of BDNF (P > 0.05), GSH (P > 0.05), or TBARS levels (P > 0.05). In conclusion, chronic SD induced memory impairment, and chronic treatment with selenium prevented this impairment by normalizing antioxidant enzymes activities in the hippocampus.

Levels of Trace Elements in Human Breast Milk in Jordan: a Comparison with Infant Formula Milk Powder.

Human breast milk and infant formula milk powder (IFMP) are the main nutritional sources for infants. In the literature, there is a lack of studies concerning levels of trace elements in human milk and IMP in Jordan. The aim of this research was the determination of levels of 24 trace elements in human breast milk from Jordanian mothers (n = 76) and IFMP from Jordanian market (n = 22). Elements were classified to essential (Mg, Fe, Zn, Cu, Mn, Ni, Cr, Mo, Co, and Se), non-essential (Al, Ag, Ba, Bi, Cs, Ga, Li, Rb, Sr, U, and V), and potentially toxic (As, Cd, and Pb). Inductively coupled plasma-mass spectrometry (ICP-MS) following a microwave digestion of samples with concentrated nitric acid and hydrogen peroxide was performed. Our results featured levels of each targeted element in human milk and IFMP (mean, standard deviation (SD), median, and range). Statistical analysis included a one-way analysis of variance (ANOVA), and Pearson's correlations. A sample toxicological analysis study for toxic elements As, Cd, and Pb was performed, and results were inspected. Levels of most elements including toxic elements are larger than in human milk samples, and comparable to in IFPMs to literature results. Mean levels of majority of the elements (17 out of 24) in human milk were significantly different than respective means in IFMP solutions. Positive correlation was observed between total toxic elements and Al, Cu, and Fe in human milk samples. Results of toxicological analysis demonstrated that most of IFMP samples do not represent a health hazard to infants regarding As, Cd, and Pb. The same applies for Cd in human milk samples. However, levels of As and Pb in 70% of human milk samples exceed the provisional tolerable weekly intake (PTWI) for As and Pb.

Plasma and saliva levels of three metals in waterpipe smokers: a case control study.

In this case-control study, the influence of waterpipe tobacco smoking on the plasma and saliva levels of cadmium, lead and zinc was examined in participants who were waterpipe tobacco smokers (WS) or never-smokers (NS). The concentration of metals was higher in WS relative to NS. The mean (SEM) cadmium concentration in plasma was 3.3 (0.18) µg/dL in WS versus 0.82 (0.09) µg/L in NS (p < .001) and in saliva was 5.1 (0.36) µg/L in WS versus 0.64 (0.2) µg/L in NS (p < .001). The mean (SEM) lead concentration in plasma was 5.2 (0.25) µg/dL in WS versus 3.4 (0.41) µg/dL in NS (p < .01) and in saliva was 4.8 (0.58) µg/L in WS versus 2.8 (0.27) µg/L in NS (p < .05). Similarly, a significant difference in zinc concentration was observed, with a mean of 2.0 (0.17) µg/mL in WS plasma versus 1.49 (0.16) µg/mL in NS (p < .05) and a mean 0.94 (0.07) µg/mL in WS saliva versus 0.45 (0.06) µg/mL in NS (p < .01). In conclusion, waterpipe tobacco smoking is associated with elevated levels of metals in body fluids. These results provide another demonstration of how waterpipe tobacco smoking exposes smokers to harmful toxicants.

Determination of selected elements in canned food sold in Jordan markets.

In this study, the concentrations of seven heavy metals including As, Cd, Cr, Cu, Ni, Pb, and Zn in imported canned food samples of different brands including tuna, beef, sardines, and mushroom were determined. Samples were collected from popular Jordanian market, Irbid city, Northern Jordan (44 samples of each type). The metal concentrations in canned food samples were found to be in the range of 1.85-4.50 µg/g for As, 0.42-0.58 µg/g for Cd, 0.47-1.67 µg/g for Cr, 0.73-0.90 µg/g for Cu, 1.08-2.77 µg/g for Ni, 2.5-3.0 µg/g for Pb, and 0.43-2.25 µg/g for Zn. Results revealed that As and Pb have the highest concentrations in all samples analyzed, whereas, the lowest concentrations obtained were in Cd. For example, in canned sardine, the mean concentrations of heavy metals are 0.43 µg/g for Zn, 2.50 µg/g for Pb, 1.74 µg/g for Ni, 0.80 µg/g for Cu, 0.47 µg/g for Cr, 0.42 µg/g for Cd, and 1.85 µg/g for As. Whereas, the mean concentrations in canned tuna were 3.48 µg/g for As, 0.47 µg/g for Cd, 0.53 µg/g for Cr, 0.73 µg/g for Cu, 2.77 µg/g for Ni, 2.80 µg/g for Pb, and 1.63 µg/g for Zn. The results of this study indicated that the concentration of the tested elements including As, Cd, Cr, Ni, and Pb in canned food samples sold in Jordanian markets exceeded the permissible limits set by health organizations such as FAO/WHO. The results were compared with the literature values.

Determination of heavy metals in canned fruits and vegetables sold in Jordan market.

In this study, the concentrations of selected heavy metals including Pb, Zn, Cr, Ni, Cu, As, and Cd in different brands of canned vegetables and fruits including canned tomato sauce (ketchup), canned green beans, canned whole carrots, and canned juice (pineapple) imported to Jordanian market were determined by acid digestion and atomic absorption spectroscopy. Samples were collected from popular Jordanian markets, Irbid city, Northern Jordan (11 samples of each type). The metal concentrations in the samples analyzed were found to be in the range of 2.6-3.0 mg/kg for Pb, 0.50-0.60 mg/kg for Cd, 2.50-5.10 mg/kg for As, 0.84-0.91 mg/kg for Cu, 0.32-3.02 mg/kg for Zn, 0.66-1.71 mg/kg for Cr, and 0.97-2.94 mg/kg for Ni. The results obtained showed that Pb and As have the highest concentrations in the most of samples analyzed, whereas, the lowest concentrations obtained were mainly in Cd. For example, in canned tomato sauce, the average concentrations of heavy metals are 3.50 mg/kg for As, 0.50 mg/kg for Cd, 0.66 mg/kg for Cr, 0.89 mg/kg for Cu, 1.15 mg/kg for Ni, 2.95 mg/kg for Pb, and 1.02 mg/kg for Zn. The results of this study reveal that the concentration of some toxic heavy metals (Pb, Cr, Ni, As, and Cd) in canned vegetable and fruit samples being sold in Jordanian markets exceeded the permissible limits set by different health organizations.

Analysis of Zn, Cd, As, Cu, Pb, and Fe in snails as bioindicators and soil samples near traffic road by ICP-OES.

Snails are used as biological indicators of the environment pollution for heavy metals. Living snail samples were collected from different sites at the city of Irbid-Jordan and classified according to their morphological features including Helix pelasga, Eobania vermiculata, Xeropicta derbentina, Oychilus, Xerocrassa seetzenii, Xerocrassa simulata, and Pila. Zn, Cd, As, Cu, Pb, and Fe levels were measured by inductively coupled plasma-optical emission spectroscopy. Results indicated that metal concentrations in all snail shell samples were with an average and range for Zn 22.4 (6.5-105.5) µg g(-1), Cd 7.8 (0.4-48.1) µg g(-1), As 25.9 (0.7-248.5) µg g(-1), Cu 15.1 (1.6-69.0) µg g(-1), Pb 0.4 (0.2-1.7) µg g(-1), and Fe 119.6 (14.0-1102.0) µg g(-1), whereas, in soil samples, the average and range for Zn 204.0 (12.0-709.0) µg g(-1), Cd 5.7 (0.2-39.5) µg g(-1), As 3.2 (1.8-5.2) µg g(-1), Cu 22.1 (2.3-77.4) µg g(-1), Pb 0.2 (0.1-0.3) µg g(-1), and Fe 242.4 (25.0-680.0) µg g(-1).

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.

A single-step extraction method for the determination of nicotine and cotinine in Jordanian smokers' blood and urine samples by RP-HPLC and GC-MS.

A simple, rapid, reliable, and low cost one-step extraction method is developed and validated for the determination of nicotine and cotinine in human plasma and urine in smokers using reversed-phase high-performance liquid chromatography (RP-HPLC) and gas chromatography-mass spectrometry (GC-MS). The run times are 16 and 10 min for HPLC and GC-MS, respectively. The method is validated over a wide linear range of 1-5000 ng/mL with correlation coefficients being consistently greater than 0.9985. The criteria considered for validation are: limit of quantitation, linearity, accuracy, precision, recovery, specificity, and selectivity. This study is aimed to estimate the nicotine and cotinine in Jordanian smokers' blood and urine samples; to study the relationship between the concentration of nicotine in urine and plasma samples; and to investigate the effect of pH on the extraction of nicotine and cotinine in urine samples. In the presented study, one hundred blood and urine samples are collected from eighty smokers and twenty nonsmokers. Samples are taken from the same volunteer at the same time after each volunteer fills in a questionnaire. Results of nicotine concentrations in smokers' plasma are in the range of 181-3702 ng/mL with an average of 1263.1 ng/mL, whereas nicotine in urine samples is in the range of 1364-1972 ng/mL, with an average of 1618 ng/mL. Cotinine concentrations in smokers' plasma are in the range of 21-4420 ng/mL with an average of 379.4 ng/mL, whereas cotinine in urine is in the range of 6-3946 ng/mL with an average of 865 ng/mL. Statistical analysis indicates highly significant differences in nicotine and cotinine concentrations in smoker samples compared with nonsmoker samples (p<0.05).

Natural Jordanian zeolite: removal of heavy metal ions from water samples using column and batch methods.

The adsorption behavior of natural Jordanian zeolites with respect to Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) was studied in order to consider its application to purity metal finishing drinking and waste water samples under different conditions such as zeolite particle size, ionic strength and initial metal ion concentration. In the present work, a new method was developed to remove the heavy metal by using a glass column as the one that used in column chromatography and to make a comparative between the batch experiment and column experiment by using natural Jordanian zeolite as adsorbent and some heavy metals as adsorbate. The column method was used using different metal ions concentrations ranged from 5 to 20 mg/L with average particle size of zeolite ranged between 90 and 350 mum, and ionic strength ranged from 0.01 to 0.05. Atomic absorption spectrometry was used for analysis of these heavy metal ions, the results obtained in this study indicated that zeolitic tuff is an efficient ion exchanger for removing heavy metals, in particular the fine particle sizes of zeolite at pH 6, whereas, no clear effect of low ionic strength values is noticed on the removal process. Equilibrium modeling of the removal showed that the adsorption of Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) were fitted to Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich (DKR). The sorption energy E determined in the DKR equation (9.129, 10.000, 10.541, and 11.180 kJ/mol for Zn(2 + ), Cu(2 + ), Cd(2 + ) and Pb(2 + ) respectively) which revealed the nature of the ion-exchange mechanism.

Evaluation of Pb, Cu, Zn, Cd, Ni and Fe levels in Rosmarinus officinalis labaiatae (Rosemary) medicinal plant and soils in selected zones in Jordan.

The concentration of heavy metals including Pb, Cu, Zn, Cd, Ni and Fe in different parts of Rosmarinus officinalis medicinal plant grown in Jordan were evaluated. Medicinal plant samples and soil samples were collected from three different zones in Jordan (Irbid, Al-Mafraq and Ma'an). Samples were analyzed by atomic absorption spectrometry (AAS) after chemical treatments using acid digestion procedures. Heavy metal levels in washed and unwashed in each part of R. officinalis were analyzed and compared statistically. Results show that concentrations of investigated heavy metals were varied from plant part to another part of R. officinalis. For example, Pb, Zn, Cu and Cd in most parts of R. officinalis in the three zones were concentrated in the following order: flowers, leaves, stems, whereas Pb, Ni and Fe were concentrated in order as follows: leaves, flowers and stems. Heavy metal concentrations in soil samples was evaluated and correlated with their levels in R. officinalis. Two standard reference materials of plant (SRM 1790a; spinach leaves and CRM 281; rye grass) and one standard reference materials of soil (GBW 07406) were examined to validate the method used. Results show that high recoveries were obtained.

Atmospheric deposition of major and trace elements in Amman, Jordan.

Wet and dry deposition samples were collected in the capital of Jordan, Amman. Concentrations of Al, Ba, Bi, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, V, Zn, Fe, Sr, Mg2+, Ca2+, Na+, K+, Cl-, NO3- and SO(4)(2-), along with pH were determined in collected samples. Mean trace metal concentrations were similar or less than those reported for other urban regions worldwide, while concentrations of Ca2+ and SO(4)(2-) were among the highest. High Ca2+ concentrations were attributed to the calcareous nature of the local soil and to the influence of the Saharan dust. However, high SO(4)(2-) concentrations were attributed to the influence of both anthropogenic and natural sources. Except for Cl-, NO3-, SO(4)(2-) and Cu, monthly dry deposition fluxes of all measured species were higher than wet deposition fluxes. The annual wet deposition fluxes of trace metals were much lower than those reported for other urban areas worldwide.

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 degrees 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.

Analysis and evaluation of nitrate levels in groundwater at Al-Hashimiya area, Jordan.

Water with high nitrate concentration (NO(3) (-)) is unfit for human consumption, especially when its concentration exceeded the threshold limit (50 mg/l) recommended by the health authorities such as the World Health Organization (WHO). In Jordan, there is a great concern for determination and monitoring organic and inorganic pollutants that may reach groundwater. Nitrate is highly mobile and present in domestic, agricultural and industrial waste in Jordan, and thus this study focused initially on nitrate as both a contaminant of concern and as an indicator of potential groundwater contamination. The present study determined the extent of nitrate contamination in groundwater in the study area and examined the likely sources of NO(3) (-). A total of 248 groundwater samples were collected from 16 wells in different sites of Al-Hashimiya area, Zerqa Governorate, Jordan, and investigated for NO(3) (-) concentrations. Moreover, measurements of temperature, electrical conductivity and pH were carried out in the field. Analysis was carried out according to the methods described by the American Public Health Association (APHA). Results showed that there was a dramatic increasing in NO(3) (-) concentrations from the year 2001 to 2006 for some selected wells in the present study. NO(3) (-) concentration in 2006 was ranged from 10 to 330 mg/l with an average of 77 mg/l. Overall, groundwater had elevated nitrate concentration with 92% of the samples containing more than 20 mg/l NO(3) (-), indicating the influence of human activities. This study has shown that there is a strong correlation between the nitrate concentration and the wastewater effluents as a source of pollution.

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 mug/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.

Fractionation and sequential extraction of heavy metals in the soil of scrapyard of discarded vehicles.

Chemical and physical size fractionation of heavy metals were carried out on 20 soil samples from the scrap yard area. Tessier method was used in sequential extraction. Cadmium showed the highest levels among the other elements studied in the exchangeable fraction (about 33%), while other elements showed low levels in this fraction (> or =1%). Lead and manganese were mostly found in the Fe-Mn oxide fraction, zinc and iron were mostly in residual fraction, while copper was mostly found in the organic fraction of the soil. Soil samples were size-fractionated into four sizes: 1000-500, 500-125, 125-53, and less than 53 microm. The highest levels of Fe, Cu, Pb, Mn, and Cd were found in the medium fraction (500-125 mum), while zinc showed its highest levels in the fine fraction (125-53 microm). The order of heavy metal load in the size fractions was found to be medium > fine > coarse > silt for Fe, Mn, Cu, Pb, and Cd, where it was found as fine > medium > coarse > silt for zinc.

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 degrees 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 in 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.

Effect of different heavy-metal concentrations on Drosophila melanogaster larval growth and development.

The survival percentage of Drosophila melanogaster larvae on synthetic media containing different concentrations of heavy metals, including Cd, Cu, Pb, and Zn, in the first generation indicated no significant reduction in their growth and development up to 500 ppm for all tested heavy-metal concentrations. At 500 ppm, results showed that there was a significant reduction in pupa and adult stages: 65% and 25% for Cd, 50% and 25% for Cu, 100% and 95% for Pb, and 85% and 75% for Zn, respectively. The survival percentages at 1000 ppm were further significantly reduced: 15% and 0% for Cd, 35% and 15% for Cu, 45% and 90% for Pb, and 65% and 35% for Zn, respectively for pupa and adult stages. For the second generation, there was no significant reduction in survival growth and development up to 100 ppm, but above 500 ppm, there was a significant reduction. For most of these heavy-metal concentrations, the survival percentages of the second generation at the pupa stage was higher than the first generation, whereas for the adult, there was a lower survival percentage, indicating some effect on metamorphosis of these heavy-metal concentrations on Drosophila melanogaster Comparing the survival percentage between first and second generations at 500 ppm for pupa indicate a significant increase on Cu only, and for the adult, there was a significant reduction for Cd.

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 immunosuppression. 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.