Characteristic levels of heavy metals in soil profiles of automobile mechanic waste dumps in Nigeria

The characteristic levels of heavy metals (Cd, Cr, Cu, Pb, Ni and Zn) of soil profiles of automobile mechanic waste dumps were studied. The concentration of heavy metals decreased with the depth of the profile and lateral distance from the dumpsites. The levels found in this study exceeded background concentrations and limits for agricultural and residential purposes. The distribution pattern of heavy metals in the soil profiles were in the following order Pb > Zn > Cu > Cd > Ni > Cr. The mechanic waste dumps represent potential sources of heavy metal pollution to environment. The elevated levels of heavy metals in these soil profiles constitute a serious threat to both surface and groundwater.     

Social, cultural and structural influences on household waste recycling: A case study

The household-recycling rate in the Borough of Burnley, England in 2001/2002 was only half the national average of 12%. This research employed both quantitative and qualitative surveys in order to ascertain whether householders’ attitudes to recycling were contributory factors to the generally poor recycling performance and to investigate other social, cultural and structural influences. The Borough has a large Asian–British population concentrated in two deprived wards where recycling rates are particularly low, so special attention was given to ascertaining their attitudes towards recycling.The quantitative survey comprised a postal questionnaire sent to a random sample of 360 households drawn from the electoral register. The qualitative survey consisted of group interviews with the Asian–British population at local community centres and focus groups attended by volunteers from the quantitative study.The findings suggest that householders are very willing to participate in recycling, as shown by the almost 80% claiming to recycle paper, but that local recycling services are too unreliable and inconvenient to allow them to do so comprehensively. Asian–British attitudes to recycling were found to be no different to those of the wider population, with their low participation being linked to the higher priorities imposed upon them by economic deprivation. The findings are broadly in line with those of the literature in that recycling participation tends to be higher among more affluent and older people, but lower among less affluent and younger households, probably due in part to the availability of both storage space and time, with the implication that the Borough's preponderance of terraced housing militates against a high recycling rate. Policy recommendations to local authorities include the provision of bespoke recycling services to suit the variety of residential conditions across the UK, and the provision of regular feedback to householders regarding recycling services and performance.Further research is needed to identify non-recyclers and to explore how householders’ underlying psychological, cultural and social attitudes to recycling impinge upon recycling and participation rates.     

WATER QUALITY DURING STORM EVENTS FROM TWO CONSTRUCTED WETLANDS RECEWING MINE DRAINAGE1

ABSTRACT: Flow rates, pH, iron concentration, and manganese concentration were measured during several storm events at two constructed wetlands receiving mine water. During a substantial rain event, flow rates at both the wetland outlets surpassed flow rates at the wetland inlets, reflecting incident rainfall and differences in wetland area at the two sites. A significant positive correlation existed between local rainfall and outflow rates at the larger wetland, but not between rainfall and inflow rates. During storm events, outlet pH, relative to inlet pH, was slightly elevated at the larger wetland, and depressed at the smaller wetland. However, over the course of one year, rainfall was uncorrelated to outlet pH in the larger wetland. A substantial rain event at the smaller wetland resulted in a temporary elevation in outlet iron concentrations, with treatment efficiency reduced to near zero. However, in the larger wetland, outlet iron concentrations were not significantly affected by storm events. Although rainfall and outlet iron concentration were not significant correlates at the larger wetland, flow rate was positively correlated to outlet iron concentration. A normal manganese treatment efficiency of 50 percent at the smaller wetland was reduced to zero during a heavy rain.     

A study on organotin levels in Canadian drinking water distributed through PVC pipes

A study on organotin compounds in Canadian drinking water was carried out in winter-spring 1996 (28 sites) and autumn 1996 (21 sites). Approximately 29% and 40% of distribution waters supplied through PVC pipes installed recently (typically less than 6 months) contained organotin compounds in the winter-spring and autumn surveys respectively. Monomethyl-, dimethyl-, monobutyl- and dibutyltin levels ranged up to 291 ng Sn/L, 49.1 ng Sn/L, 28.5 ng Sn/L and 52.3 ng Sn/L, respectively. An additional study in summer 1996, of locations where the highest organotin levels were detected in the winter-spring survey, indicated that organotin levels had decreased in most distribution water samples. Samples of PVC pipe/tubing contained organotin compounds consistent with the organotin patterns found in the distribution water samples.     

Does temperature modify short-term effects of ozone on total mortality in 60 large eastern US communities? An assessment using the NMMAPS data

Many studies have indicated that ozone is associated with morbidity and mortality. A few studies have reported that the association is heterogeneous across seasons and geographic regions. However, little information is available on whether both temperature and geographic factors simultaneously modify the ozone effect. This study used a Poisson regression model to explore whether temperature modifies the effect of ozone on mortality in the 60 large eastern US communities during April to October, 1987-2000. Results show that temperature modified ozone-mortality associations and that such modification varied across geographic regions. In the northeast region, a 10-ppb increment in ozone was associated with an increase of 2.22% (95% posterior interval [PI]: 1.19%, 3.13%), 3.06% (95% PI: 2.21%, 3.76%) and 6.22% (95% PI: 4.77%, 7.56%) in mortality at low, moderate and high temperature level, respectively, while in the southeast region a 10-ppb increment in ozone was associated with an increase of 1.13% (95% PI:-1.12%, 3.18%), 1.50% (95% PI: 0.22%, 2.81%) and 1.29% (95% PI:-0.33%, 2.96%) in mortality, respectively. We concluded that temperature synergistically modified the ozone-mortality association in the northeast region, but such a pattern was not apparent in the southeast region. Thus, both temperature and geographic factors should be considered in the assessment of ozone effects.     

A global evaluation of metabolic theory as an explanation for terrestrial species richness gradients

We compiled 46 broadscale data sets of species richness for a wide range of terrestrial plant, invertebrate, and ectothermic vertebrate groups in all parts of the world to test the ability of metabolic theory to account for observed diversity gradients. The theory makes two related predictions: (1) In-transformed richness is linearly associated with a linear, inverse transformation of annual temperature, and (2) the slope of the relationship is near -0.65. Of the 46 data sets, 14 had no significant relationship; of the remaining 32, nine were linear, meeting prediction 1. Model I (ordinary least squares, OLS) and model II (reduced major axis, RMA) regressions then tested the linear slopes against prediction 2. In the 23 data sets having nonlinear relationships between richness and temperature, split-line regression divided the data into linear components, and regressions were done on each component to test prediction 2 for subsets of the data. Of the 46 data sets analyzed in their entirety using OLS regression, one was consistent with metabolic theory (meeting both predictions), and one was possibly consistent. Using RMA regression, no data sets were consistent. Of 67 analyses of prediction 2 using OLS regression on all linear data sets and subsets, two were consistent with the prediction, and four were possibly consistent. Using RMA regression, one was consistent (albeit weakly), and four were possibly consistent. We also found that the relationship between richness and temperature is both taxonomically and geographically conditional, and there is no evidence for a universal response of diversity to temperature. Meta-analyses confirmed significant heterogeneity in slopes among data sets, and the combined slopes across studies were significantly lower than the range of slopes predicted by metabolic theory based on both OLS and RMA regressions. We conclude that metabolic theory, as currently formulated, is a poor predictor of observed diversity gradients in most terrestrial systems.     

Water Planning and Hydro-Climatic Change in the Murray-Darling Basin,Australia

More than a third of humanity lives in regions with less than 1 million liters of fresh water per person per year. Population growth will increase water demand while climate change in arid and semi-arid areas may reduce water availability. The Murray-Darling Basin in Australia is a region where water reform and planning have been used to reduce consumptive extraction to better sustain river ecosystems under climate variability. Using actual data and previously published models that account for climate variability and climate change, the trade-off between water extractions and water essential to the long-term ecological function of river systems is analysed. The findings indicate that better water planning and a more complete understanding of the effects of irrigation on regional climate evapotranspiration could: (1) increase the overall benefits of consumptive and non-consumptive water use; (2) improve riparian environments under climate variability; and (3) be achieved with only small effects on the profits and gross value of food and fiber production.     

Development and Evaluation of a Method to Determine Indicator Microorganisms in Air Emissions and Residue from Medical Waste Incinerators

To allow testing of microbial destruction in medical waste incinerators, methods were developed to determine indicator microorganisms (Bacillus Stearothermophilus spores) in incinerator air emissions and residue. The emission trapping train consisted of a water cooled glass probe and impingers containing a neutral phosphate buffer. In field tests, spores were injected directly into the probe, and results showed that approximately 60 percent of the spores were recovered. Spores were analyzed with adequate precision using a microbial membrane filter unit. Lab experiments indicated that spores were stable in neutral pH phosphate buffer for up to 20 days, and heat shocking samples (heating to 80°C for 20 minutes) reduced spore numbers in acidic or basic buffer. Laboratory tests also showed that 60 to 70 percent of spores initially added to ash were recovered up to 22 days after addition of the spores. In addition, lab tests showed that spores can be effectively recovered from residue test pipes spiked with indicator spores.     

Lessons from the 2006 Louisiana health and population survey

The 2005 hurricane season caused extensive damage and induced a mass migration of approximately 1.1 million people from southern Louisiana in the United States. Current and accurate estimates of population size and demographics and an assessment of the critical needs for public services were required to guide recovery efforts. Since forecasts using pre-hurricane data may produce inaccurate estimates of the post-hurricane population, a household survey in 18 hurricane-affected parishes was conducted to provide timely and credible information on the size of these populations, their demographics and their condition. This paper describes the methods used, the challenges encountered, and the key factors for successful implementation. This post-disaster survey was unique because it identified the needs of the people in the affected parishes and quantified the number of people with these needs. Consequently, this survey established new population and health indicator baselines that otherwise would have not been available to guide the relief and recovery efforts in southern Louisiana.