Journal of

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Introduction: Recent investigations have detected the presence of significant levels of heavy metals (chromium, lead and cadmium) in toys and other PVC products manufactured for children. In some countries, addition of compounds containing toxic metals to toys are limited or prohibited. Methods: To evaluate the safety of some of the plastic toys in the city of Isfahan with respect to toxic trace metals, pb, cr and cd, 75 samples of three types of toys were collected from the toy shop’s and were digested with acid with the two methods ISIRI and ASTM. The heavy metals were determined using atomic absorption spectrophotometer. Variance analysis and T-test were used for data analysis. Results: The result of the study showed that the products tested contained lead, chromium and cadmium and the highest and lowest concentration were related to Pb and Cd, respectively. The statistical analysis of the samples showed that there are no significant differences between ASTM and ISIRI digestion methods. The study revealed that none of the heavy metals in the toy samples exceeded the recommended standard levels. Highest average concentration of Pb and Cd were related to toys with green color and the highest Cr concentration was related to yellow toys in this study. Conclusion: Extensive studies are required to evaluate the quality of the toys being used by children and the toxic trace elements should be eliminated from the plastic materials used for making toys.

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Introduction: The extensive use of Lead has led to health problems including CNS, anemia and other occupational poisoning among workers. To determine the blood lead levels in relation to demographic factors, this study was carried out. Methods: In this cross sectional study, 490 workers at Kooshk Lead and Zinc mine were selected and blood samples were taken. The blood lead levels were assessed according to the NIOSH standard using atomic absorption. Results: The mean, minimum and maximum of blood lead levels were 49, 9 and 116 mg/dl, respectively. The blood lead levels in 45.7 percent of workers was more than permissible limit. The blood lead level was not significantly related to age and history of work. The lowest and highest levels of blood lead were 9 & 116 mg/dl, respectively. In contrast, significant relationship was seen between the location of work and blood lead level. The results showed that in the majority of workers with blood lead levels higher than standard limit, there was a significant relationship between the blood Lead levels and the hemoglobin concentration. The blood lead level in 45% of samples was more than Iranian standards. Conclusion: The work location was the main factor affecting the blood lead levels. Attention should therefore be focused on the alteration of RBC and Hemoglobin levels during periodic medical examination of workers

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Introduction: With industrialization of human societies, pollutants like lead have entered in the life cycle, causing harmful effects on body organs. No sufficient studies have been done on the effects of pollutants on behavior. The aim of this study was to investigate possible effects of lead on some measurable behaviors of an animal model. Methods: Forty eight male adult mice were divided into 4 groups of 12 each. Lead acetate was added at concentrations of 0, 5, 50, or 500 ppm to the drinking water of the animals for 4 weeks (28 days). On day 29, animals were placed on an Elevated Plus maze (EPM) for 5 min and the time in sec spent was measured on closed arms, open arms and the end 1/3rd of the open arms. Increased time on open arms, particularly the end 1/3rd was considered to reflect an enhanced risk-accepting behavior. Results: In this study, it was shown that lead exposure caused an increased number of entrance (P=0.006) and time spent (P=0.034) by mice on open arms of the EPM. There was a positive correlation between the concentration of lead acetate and those two effects. Conclusion: The present study demonstrated that lead poisoning may decrease normal anxiety in mice and increase risky behavior in this species. Clinical studies on human subjects with risky behavior are strongly suggested in order to find a possible relation between chronic exposures to lead as well as plasma concentration of lead with the extent of this kind of behavior.

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Introduction: Influences of lead on functions of many organ systems are known, but less experimental studies has been done on influences over the behavior, including pain sensation. This study was carried out to reveal possible changes in the onset and intensity of reactions to painful stimuli in mice, after long-term exposure to lead acetate.

Methods: In this experimental study, 24 adult male albino mice were divided randomly into 3 groups of 8 each. Control group received fresh water ad lib and 2 treated groups received drinking water contaminated by either 5 ppm or 500 ppm of LA for 90 consecutive days. On the day of 91, nociceptive were performed using a hot plate and formalin, to evaluate onset and intensity of  reaction in response to the thermal and chemical pain, respectively. At the end, the animals were euthanized and blood samples were collected for determination of cortisol levels using an ELISA assay.

Results: The animals exposed to LA showed a delay in reaction to painful stimuli induced by thermal stimulus by 52% and 59% with low and high doses, respectively. Thermal pain intensity of reactions to was declined by 63% with LA 5 ppm and by 82% with LA 500 ppm (P<0.05). Delayed reaction to chemical stimulus was also prominent in treated groups up to 68% and the pain intensity was declined by 80%, but they were not statistically significant. Blood cortisol levels remained almost unchanged.

Conclusion: Delayed reaction to painful stimuli after chronic LA exposure may be considered as a complication which weaken the alarming role of the pain. Further studies regarding the mechanism of action and the extent of the importance of these effects are warranted.