Predicted intake of trace elements and minerals via household drinking water by 6-year-old children from Kraków, Poland. Part 2: Cadmium, 1997–2001

Tap Water Consumption Is Associated with Schoolchildren’s Cognitive Deficits in Afghanistan

Environmental influence on intelligence quotient (IQ) is poorly understood in developing countries. We conducted the first cross-sectional investigation to assess the role of socio-economic and environmental factors on schoolchildren’s IQ in Jalalabad, Afghanistan. A representative sample of 245 schoolchildren aged 7–15 was randomly selected in five schools. Children’s records included: non-verbal IQ TONI-1 scale, body mass index, socio-economic status, and further environmental indicators (water supply, proximity to a heavy-traffic road, use of surma traditional cosmetics). The mean age of the children was 11.7 years old (±2.0 years), and 70.2% and 29.8% were male and female, respectively. The children’s mean IQ was 83.8 (±12.6). In total, 37 (14.9%) of the children were overweight, 78 (31.5%) were living below the USD 1.25 poverty line, 133 (53.6%) used tap water supply, 76 (30.6%) used surma, and 166 (66.9%) were exposed to heavy road traffic. The children’s IQ was significantly and independently lowered by tap water use (−3.9; 95% CI [−7.1; −0.6]) and by aging (−1.4; 95% CI [−2.2; −0.6]), as revealed in multivariate analysis, independently of gender, socio-economic status, exposure to heavy road traffic, overweight status, and surma use. Lower IQ among older children is possibly attributed to chronic stress experienced by adolescents due to living conditions in Afghanistan. While using tap water prevents fecal peril, it may expose children to toxic elements such as lead which is known to lower their intellectual development.

In-site and solvent-free exfoliation of porous graphene oxide from pencil lead fiber for solid-phase microextraction of cadmium ion before GF-AAS determination

Graphene oxide (GO)-functionalized pencil lead fiber was prepared for the first time by in situ oxidation and exfoliation of graphite contained in pencil lead fiber to porous graphene oxide structure via a one-step solvent-free dielectric barrier discharge (DBD) microplasma treatment. This new fiber was demonstrated as a highly efficient and low-cost solid-phase microextraction (SPME) fiber for the determination of toxic metal ions. The fiber extraction performance was evaluated by using cadmium as a model analyte in a direct immersing SPME mode. Unlike most commercially available and other lab-built fibers, the preparation of the graphene oxidized pencil lead fiber is environmentally friendly, low cost, and non-toxic without using any organic solvents. The fiber is robust due to its coating-free configuration. Furthermore, high extraction efficiency and high sensitivity for cadmium can be obtained due to the abundant oxygen-containing functional groups on the surface of the novel fiber. After extraction, the cadmium adsorbed on the fiber was desorbed to 150-μL solution. Graphite furnace atomic absorption spectrometry (GF-AAS) with low sample consumption was used to determine cadmium. The calibration curve for cadmium ions was linear in a range 0.04-0.26 μg L^-1 with a detection limit of 0.005 μg L^-1. A relative standard deviation (RSD, n = 5) of 2.1% was obtained at 0.1 μg L^-1 of cadmium. The sensitivity enhancement factor (EF) value of the proposed SPME method was 25. The SPME fiber was successfully applied to determine cadmium in tap water, river water, and pond water with spike recoveries ranging from 94 to 105%. Pipe network water samples were also analyzed to evaluate the cadmium release to drinking water due to the corrosion of tubes.

Toxicological analysis of Pb and Cd by ET AAS in local anaesthetics for teething (teething gels) based on herbs available in Polish pharmacies

Studies related to the toxicological analyses of metallic impurities in pharmaceuticals (drugs) is an important issue but there is a lack of refereed literature around the safety of teething remedies from herbal origin related to toxic metals impurities. In this article, the levels of Pb and Cd were measured in samples of local anaesthetics for teething (gels) based on herbs. This article was motivated by the fact that Pb and Cd are relevant toxic metals that may cause an adverse effect in babies even at low levels. Additional justifications were (1) the insufficient control of metal impurities in teething gels, (2) the lack of sufficient validation steps and (3) the inadequate sensitivity of applied analytical techniques. The aim of this article was a qualitative and quantitative analysis of Pb and Cd in the most popular and available local anaesthetic for teething (teething gels) based on herbs (n = 5) available in Poland. Metals were determined by ET AAS (electrothermal atomization atomic absorption spectrometry), after digestion in a microwave unit using concentrated nitric acid. It was observed that all samples contained Pb and Cd. The levels of Pb and Cd as impurities (independently of the producer and declared composition) are similar. The concentrations of Pb and Cd, at ng/day levels, to which the user is exposed at daily doses meet the standards of the directive ICH Q3D.

Characteristics of pipe corrosion scales in untreated water distribution system and effect on water quality in Peshawar, Pakistan

This study investigated the characteristics of iron corrosion scales in pipes at tube well, overhead tank, and consumers' end in older untreated water distribution system in Peshawar city, Pakistan. Effect of water quality conditions on corrosion scales and that of scales on drinking water quality in such systems was also assessed by undertaking a comparison with new piped distribution systems. The scales were analyzed for chemical composition and morphology using X-ray diffraction (XRD), inductively coupled plasma (ICP), and a scanning electron microscope (SEM), while water quality was examined for physicochemical and biological characteristics. The main crystalline phases of corrosion scales were goethite, magnetite, siderite, and quartz. From tube well to consumers' end, goethite increased from 36 up to 48%, quartz declined from 22 to 15%, while magnetite fluctuated and siderite disappeared. Elemental composition of scales showed the deposition of Zn, Al, Mn, Cr, Pb, Cu, As, and Cd with Zn (13.9 g/kg) and Al (3.6 g/kg) in highest proportion. The SEM analysis illustrated the presence of microbial communities indicating the formation of biofilms in the corrosion scales. The significant difference (P < 0.05) in levels of dissolved oxygen (DO), Cl^-, SiO₄^4-, electrical conductivity (EC), SO₄^2-, NO₃^-, alkalinity, hardness, and trace metals between old (DS-O) and new piped systems indicated their role in corrosion scale formation/destabilization and the effect of scale dissolution on water quality. In DS-O, EC, Cu, and Mn were significantly higher (P < 0.05), whereas turbidity, EC, DO, and SiO₄^4- significantly increased from source to consumers' end implying a higher dissolution of scales and lowered corrosion rates in DS-O to utilize SiO₄^4- and DO for iron oxidation.

The toxicological analysis of lead and cadmium in prescription food for special medical purposes and modified milk products for newborns and infants available in Polish pharmacies

There is currently a lack of risk assessments around Pb and Cd in prescription food for special medical purposes (FSMPs) and modified milk products available in from pharmacies in Poland. This article describes and evaluates a toxicological analysis of lead and cadmium in prescription FSMPs (n = 6) and modified milk products (n = 6) available in Polish pharmacies. The metals were determined using electrothermal atomisation atomic absorption spectrometry. To make the appropriate risk assessment, we considered (1) the levels of lead and cadmium in a powdered product, (2) the amount of the metals consumed in one portion (single exposure), (3) the daily dose depending on age (months) and body weight and (4) the weekly intake of Pb and Cd in samples in comparison to provisional tolerable weekly intake (PTWI). The results demonstrated that the samples analysed do not represent a health hazard to newborns and infants. This study is important because of the concerns around the complex risk assessment of prescription FSMP's and modified milk products available in Polish pharmacies related to lead and cadmium.

Advantages of the use of deciduous teeth, hair, and blood analysis for lead and cadmium bio-monitoring in children. A study of 6-year-old children from Krakow (Poland)

The population of about 300 6-year-old preschool children was studied for lead (Pb) and cadmium (Cd) in deciduous teeth, scalp hair, and capillary blood. Zinc (Zn) content in hair was also measured due to its possible interferences with the elements studied. The Pb and Cd contents were measured by graphite furnace atomic absorption spectrometry with Zeeman background correction, and Zn, by flame method. Metal levels found were comparable to those in European countries. Positive correlations between Pb and Cd in the same and different tissues were widespread (r=0.23-0.68). A positive correlation was found between Pb in teeth and blood (r=0.65, p<0.001). Pb blood threshold 100 μg L(-1) referred to 2.6 μg g(-1) Pb in teeth. Predictability of this Pb teeth limit was 14% vs. 5% for Pb blood. Strong negative correlation was found between hair Pb and Zn (r=-0.68, p<0.001). Enhanced Cd and Zn levels in hair were associated with the household drinking water hardness. The associations with some other environmental and behavioral factors were also presented and discussed. The results proved the advantage of analysis of primary teeth for Pb exposure screening of preschool children.