Journal of School of Public Health and

---

 

  Background and Aim: The aim of this study was to assess exposure of workers in a metal industry to nickel and lead.

  Materials and Methods: Extraction was done using the solid-phase extraction on Chromosorb-102 resin to prepare, concentrate and purify biological samples of urine, hair and nails of workers working in metal industries. The variables influencing response (pH, loading flow rate, elution solvent, and amount of resins, elution volume, and sample volume) were examined and the procedure was optimized. The optimized procedure was, then, validated based on the “within-day” and “day-to-day” reproducibility experiments, using low, medium and high concentrations, leading to a satisfactory accuracy and precision. Finally, lead and nickel samples were taken from the workers and their concentrations determined voltammetrically.

  Results: The optimum values for the examined parameters were as follows: pH = 9, ligand concentration = 0.05%, loading flow rate = 5 ml/min, elution solvent = 2M HNO₃, amount of resins = 500 mg, elution volume = 15 ml, and sample volume up to 500 ml. A good reproducibility and repeatability was obtained for the optimized method under the existing conditions. Lead and nickel could be extracted with recoveries in the range of 94-100%. On the whole, the concentrations of nickel and lead in the workers’ biological samples were above the respective maximum permitted levels.

  Conclusion: Solid-phase extraction procedure is a fast and simple method for preconcentrating and isolating analytes from biological samples. Considering the low concentrations of the analytes and presence of confounding factors in such samples, the procedure can be very effective for their preparation. The application of the developed method indicates that trace metal ions can be effectively purified and preconcentrated from different matrices like urine, hair and nail samples to assess occupational exposures.

---

Background and Aim: Considering the importance of children's dietary patterns in the general health and vitality of the population in the future and the effect of maternal depression on performing maternal tasks  and responsibilities regarding children's eating habits and behaviors, this study was designed and conducted to determine the relationship between maternal depression and children's dietary patterns.
Materials and Methods: This cross-sectional descriptive-analytical study included 313 primary school children in Tehran in the first semester of the academic year 2018-2019 selected through stratified cluster sampling. The following questionaires were used to collect the data: general and demographic questionnaires  related to mothers and children, the Beck standard questionnaire to assess maternal depression, and a food frequency questionnaire to assess the children’s food patterns. The SPSS-22 and Stata-13 were used to analyze the data. Using exploratory factor analysis the dominant food patterns of the children were determined. The statistical tests used for data analysis included descriptive statistics, Mann-Whitney, Kruskal-Wallis and Pearson and Spearman correlation coefficients.
Results: Data analysis showed the prevalence of depression among the mothers and the dominant dietary pattern among the children to be 31.3% (n=98)  and vegetarian dietary patterns, respectively. The children’s body mass index, heights and waist circumference were significantly positively associated with with some of the dietary patterns (p<0.05). However, no significant association was found between maternal depression and the children's dietary patterns (p>0.05).
Conclusion: According to the findings of this study, maternal depression has no significant association with children's dietary patterns. Conducting similar studies with larger sample sizes are recommended.