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.

Stochastic Mechanochemical Description of a Bioinspired Polymerization Process.

We present a theoretical investigation of a polymerization process catalyzed by an enzyme. A structural model of enzyme, sliding along the polymer chain as a Brownian particle, is proposed, and a stochastic approach is employed to describe the kinetics of the whole process. The key point of this work is the coupling mechanics/chemistry obtained by assuming that (1) some rates of chemical reaction depend on the position of the enzyme with respect to the polymer chain and (2) the potential energy and the friction coefficient in the Langevin equation depend on the chemical state of the polymerizing complex.

210Po and 210Pb trophic transfer within the phytoplankton-zooplankton-anchovy/sardine food web: a case study from the Gulf of Lion (NW Mediterranean Sea).

The transfer of (210)Po and (210)Pb in the food web of small pelagic fishes (from phytoplankton and zooplankton to anchovy Engraulis encrasicolus and sardine Sardina pilchardus) is investigated in the Gulf of Lion (GoL). We present original data of (210)Po and (210)Pb activity concentrations, C and N stable isotope ratios, measured (i) from different size classes of phytoplankton and zooplankton during spring and winter in different environments of the GoL, and (ii) in two fish species. Significant spatial patterns based on (210)Po, (210)Pb activity concentrations and (210)Po/(210)Pb ratios in the different plankton size classes are evidenced by hierarchical clustering, both in spring and winter.

Using S and Pb isotope ratios to trace leaching of toxic substances from an acid-impacted industrial-waste landfill (Pozdatky, Czech Republic).

Slightly elevated concentrations of toxic species in waters sampled in the surroundings of a leaky landfill may be both a sign of an approaching contaminant plume, or a result of water-rock interaction. Isotopes can be instrumental in distinguishing between anthropogenic and geogenic species in groundwater. We studied sulfur and lead isotope ratios at an abandoned industrial-waste landfill, located in a densely populated part of Central Europe.

Lead isotopes reveal different sources of lead in balsamic and other vinegars.

Fifty-eight brands of balsamic vinegars were analyzed for lead concentrations and isotopic compositions ((204)Pb, (206)Pb, (207)Pb, and (208)Pb) to test the findings of a previous study indicating relatively high levels of lead contamination in some of those vinegars--more than two thirds (70%) of them exceeded California's State Maximum Level (34 μg/L) based on consumption rates ≥0.5 μg Pb per day. The lead isotopic fingerprints of all those vinegars with high lead concentrations were then found to be primarily anthropogenic.

Origin of lead in eight Central European peat bogs determined from isotope ratios, strengths, and operation times of regional pollution sources.

Lead originating from coal burning, gasoline burning, and ore smelting was identified in 210Pb-dated profiles through eight peat bogs distributed over an area of 60,000 km2. The Sphagnum-dominated bogs were located mainly in mountainous regions of the Czech Republic bordering with Germany, Austria, and Poland. Basal peat 14C-dated at 11,000 years BP had a relatively high 206Pb/207Pb ratio (1.

European isotopic signatures for lead in atmospheric aerosols: a source apportionment based upon 206Pb/207Pb ratios.

To investigate the capability of the lead isotope signature technique to support a source apportionment study at a Continental scale, atmospheric particulate matter was collected at Cap Gris-Nez (Eastern Channel, northern France), over one year (1995-1996). Four days retrospective trajectories of air masses were available during each sampling experiment. Twenty-eight samples, for which the origin of aerosols was unambiguously determined, were selected for isotopic measurements.

Transboundary atmospheric lead pollution.

A high-temporal resolution collection technique was applied to refine aerosol sampling in Jerusalem, Israel. Using stable lead isotopes, lead concentrations, synoptic data, and atmospheric modeling, we demonstrate that lead detected in the atmosphere of Jerusalem is not only anthropogenic lead of local origin but also lead emitted in other countries. Fifty-seven percent of the collected samples contained a nontrivial fraction of foreign atmospheric lead and had 206Pb/207Pb values which deviated from the local petrol-lead value (206Pb/207Pb = 1.