Frequency versus time lost measures of absenteeism: Is the voluntariness distinction an urban legend?

We investigate a long‐standing methodological rule of thumb, the idea that the frequency of absenteeism from work approximates an expression of voluntary behavior while total time lost better reflects involuntary behavior and ill health. Conducting original meta‐analyses and using results from existing meta‐analyses, we determine that time lost and frequency are equally reliable, that the relationship between them approximates unity when corrections for measurement artifacts are applied, and that there is very little evidence for differential criterion‐related validity predicated on the voluntariness distinction. We supply new meta‐analytic estimates of the reliability of absenteeism adjusted for aggregation period and determine that most extant meta‐analyses of the correlates of absenteeism have markedly under‐corrected for unreliability. Our results question the basic construct validity of the time lost–frequency distinction, and they contradict the practice of using “trigger points” that factor absence frequency into attendance monitoring and associated discipline systems so as to discourage short‐term absenteeism, assumed to be volitional. We conclude that the idea that time lost and frequency reflect different degrees of voluntariness is an unsupported urban research legend. Copyright © 2015 John Wiley & Sons, Ltd.     

Human dietary intake and hazard characterization for residues of neonicotinoides and organophosphorus pesticides in Egyptian honey

In two recently published reports, hazards posed by dietary exposure to organophosphate and neonicotinoid plant protection products on the European honey bee (Apis mellifera L.) in Egypt were investigated. Using concentrations reported in those studies, an assessment of hazards posed by these two classes of insecticides to humans due to consumption of Egyptian honey from the Nile Delta during both spring and summer was performed. Twenty-eight compounds including metabolites were assessed for exposure of adult Egyptians based on the best- and worst-case scenarios. Even for the worst-case scenario, exposure to these two classes of pesticides in honey was 15-fold less than hazard index value of 1.0 for adverse effects on humans. Based upon this analysis, people exposed to these insecticides through consumption of honey products would be unlikely to exhibit adverse health outcomes.     

Groundwater vulnerability to selenium in semi-arid environments: Amman Zarqa Basin,Jordan

An evaluation of ~250 samples of groundwater in the Amman Zarqa Basin for selenium along with other major and trace elements showed that concentrations of Se ranged between 0.09 and 742 μg/L, with an average value of about 24 μg/L. Selenium concentrations exceeded the recommended threshold for drinking water of the World Health Organization (WHO; 10 μ/L of Se) in 114 samples, with greater than 50 μg/L (quantity equivalent to the Jordanian standard of the allowed concentration of the element in water) of Se in nine cases. The average concentrations of Se in the lower, middle, and upper aquifers of the basin were 3.41, 32.99, and 9.19 μg/L, respectively. Based on the correlation with geologic formations and the statistical analysis of major/minor constituents and Piper tri-linear diagrams, we suggest that carbonate/phosphate dissolution, oxidation–reduction processes, and fertilizers/irrigation return flow are, together, the primary factors affecting the chemistry of the groundwater. Factor analysis helped to define the relative role of limestone-dolomitic dissolution in the aquifers (calcium, magnesium, and bicarbonate), agricultural activities (sulfate, nitrates, phosphorus, and potassium), oxidation–reduction factor (Eh, Fe, Mn, Cu, Zn, and Se), and anthropogenic (industrial) factor (EC, Fe, Cr, Co, Zn, and As). The high variability in Se concentrations might be related to the possibility of a multi-source origin of Se in the area.     

Utilization of sludge from water treatment plant as a filler material in pavements

Journal of Material Cycles and Waste Management - The recycling potential of water treatment plant (WTP) sludge in asphalt concrete mixes as filler material was assessed in this study. Marshall...     

Urban stormwater runoff pollutant loadings: GIS land use classification vs. sample-based predictions

Environmental Science and Pollution Research - Cities are growing worldwide with an increase in stormwater quantity and decrease in quality, negatively impacting receiving water bodies. The...     

In situ biofilm barriers: Case study of a nitrate groundwater plume,Albuquerque, New Mexico

A new use for biofilm barriers was developed and successfully applied to treat nitrate‐contaminated groundwater down to drinking water standards. The barrier was created by stimulating indigenous bacteria with injections of molasses as the carbon donor and a combination of yeast extract and trimetaphosphate as nutrients. This injection of amendments results in bacterial growth in the aquifer, which attaches to the sand grains to create a reactive semipermeable biofilm. The biofilm barrier presented in this article reduced the migration of contaminants and provided an active zone for remediation. The cylindrical biobarrier was constructed using eight wells on the perimeter forming a 60‐foot‐diameter reactive biodenitrification region. Another well at the center was installed to continuously extract the treated water. The intent was to produce a continuous source of nitrate‐free water. The system operated for over one year, and during this period, the biobarrier was revived multiple times by reinjecting molasses in the perimeter wells. Nitrate concentrations of treated water decreased from 275 mg/L (as nitrogen) to < 1 mg/L. © 2005 Wiley Periodicals, Inc.     

Radiological impacts of phosphogypsum

This study was carried out to assess the radiological impact of Syrian phosphogypsum (PG) piles in the compartments of the surrounding ecosystem. Estimating the distribution of naturally occurring radionuclides (i.e. (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb) in the raw materials, product and by-product of the Syrian phosphate fertilizer industry was essential. The data revealed that the concentrations of the radionuclides were enhanced in the treated phosphate ore. In PG, (226)Ra content had a mean activity of 318 Bq kg(-1). The uranium content in PG was low, ca. 33 Bq kg(-1), because uranium remained in the phosphoric acid produced. Over 80% of (232)Th, (210)Po and (210)Pb present partitioned in PG. The presence of PG piles did not increase significantly the concentration of (222)Rn or gamma rays exposure dose in the area studied. The annual effective dose was only 0.082 mSv y(-1). The geometric mean of total suspended air particulates (TSP) ca. 85 μg m(-3). The activity concentration of the radionuclides in filtrates and runoff waters were below the detection limits (ca. 0.15 mBq L(-1) for (238)U, 0.1 mBq L(-1) for (232)Th and 0.18 mBq L(-1) for both of (210)Po and (210)Pb); the concentration of the radionuclides in ground water samples and Qattina Lake were less than the permissible limits set for drinking water by the World Health Organisation, WHO, (10, 1 and 0.1 Bq L(-1) for (238)U, (232)Th and both of (210)Po and (210)Pb, respectively). Eastern sites soil samples of PG piles recorded the highest activity concentrations, i.e. 26, 33, 28, 61 and 40 Bq kg(-1) for (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb, respectively, due to the prevailing western and north-western wind in the area, but remained within the natural levels reported in Syrian soil (13-32 Bq kg(-1) for (226)Ra, 24.9-62.2 Bq kg(-1) for (238)U and 10-32 Bq kg(-1) for (232)Th). The impact of PG piles on plants varied upon the plant species. Higher concentrations of the radionuclides were recorded for grass in comparison to broad-leaved plants. Among the species that grow naturally on PG piles, Inula, Ecballium and Polygonium may be radionuclides accumulators. A determined effort is needed at a national level to achieve a common and coherent approach to regulate PG piles or to consider it a resource material rather than waste or residue.