Consumption of unsafe food in the adjacent area of Hazaribag tannery campus and Buriganga River embankments of Bangladesh: heavy metal contamination

The concentrations of Cr, Cd, Pb, Hg, and As in water, poultry meat, fish, vegetables, and rice plants obtained from the area adjacent to the Hazaribag tannery campus, Dhaka, Bangladesh, were estimated and compared with permissible levels established by the WHO and FAO and levels reported previously by other authors. The metal contents were in the following order according to the concentration in contaminated irrigation water: Cr?>?Pb?>?As?>?Hg?>?Cd. Mean concentrations of Cr, Pb, Hg, and As in irrigated water were above the permissible levels, whereas the results were below the permissible levels for Cd. The metal concentrations in poultry meat, fish, rice, and vegetables were in the following orders: Pb?>?Cr?>?Cd?>?Hg?>?As, Pb?>?Cr?>?Cd?>?As?>?Hg, Pb?>?As, and Cr?>?Pb?>?Cd?>?As?>?Hg, respectively. The mean concentrations of metals in poultry meat, fish, rice, and vegetables were much higher than the permissible levels. The trends of weekly intake of heavy metals (WIMs) from poultry meat, fish, rice, and vegetables were as follows: Pb?>?Cr?>?Cd?>?Hg?>?As, Pb?>?Cr?>?Cd?>?As?>?Hg, Pb?>?As, and Cr?>?Pb?>?Cd?>?As?>?Hg, respectively. WIMs for all the metals were lower than the provisional maximum weekly intake recommended by WHO/FAO and USNAS.     

Household solid waste characteristics and management in Chittagong, Bangladesh

Solid waste management (SWM) is a multidimensional challenge faced by urban authorities, especially in developing countries like Bangladesh. We investigated per capita waste generation by residents, its composition, and the households' attitudes towards waste management at Rahman Nagar Residential Area, Chittagong, Bangladesh. The study involved a structured questionnaire and encompassed 75 households from five different socioeconomic groups (SEGs): low (LSEG), lower middle (LMSEG), middle (MSEG), upper middle (UMSEG) and high (HSEG). Wastes, collected from all of the groups of households, were segregated and weighed. Waste generation was 1.3kg/household/day and 0.25kg/person/day. Household solid waste (HSW) was comprised of nine categories of wastes with vegetable/food waste being the largest component (62%). Vegetable/food waste generation increased from the HSEG (47%) to the LSEG (88%). By weight, 66% of the waste was compostable in nature. The generation of HSW was positively correlated with family size (r(xy)=0.236, p<0.05), education level (r(xy)=0.244, p<0.05) and monthly income (r(xy)=0.671, p<0.01) of the households. Municipal authorities are usually the responsible agencies for solid waste collection and disposal, but the magnitude of the problem is well beyond the ability of any municipal government to tackle. Hence dwellers were found to take the service from the local waste management initiative. Of the respondents, an impressive 44% were willing to pay US$0.3 to US$0.4 per month to waste collectors and it is recommended that service charge be based on the volume of waste generated by households. Almost a quarter (22.7%) of the respondents preferred 12-1pm as the time period for their waste to be collected. This study adequately shows that household solid waste can be converted from burden to resource through segregation at the source, since people are aware of their role in this direction provided a mechanism to assist them in this pursuit exists and the burden is distributed according to the amount of waste generated.     

Differential livelihood adaptation to social-ecological change in coastal Bangladesh

Regional Environmental Change - Social-ecological changes, brought about by the rapid growth of the aquaculture industry and the increased occurrence of climatic stressors, have significantly...     

Multi‐strainer model concept for conjunctive pumping of saline and non‐saline groundwater from coastal aquifers

The current paper discusses the multi‐strainer technique developed to augment usable water by the combined use of saline and non‐saline aquifers in locations where a freshwater aquifer is underlain or overlain by a saline water aquifer. The multi‐strainer technique evaluates design criteria for the formulation of multi‐strainer schemes to supply water at an acceptable salinity limit by combined use of the saline and non‐saline aquifers. The design ratio of discharges can be maintained by adjusting the strainers’ lengths in the saline and non‐saline aquifers. The multi‐strainer scheme has been applied in the coastal aquifers of Bangladesh and found to be effective at lowering the water salinity concentrations to acceptable levels, thus increasing the availability of water for sustainable use. The multi‐strainer scheme should be designed based on the thickness of the aquifer layers to be screened, the salinity concentrations of the screened layers, and the level of salinity concentration to be maintained.     

Restraint use in the Eastern Province of the Kingdom of Saudi Arabia

Objectives: This study set out to examine seat belt and child restraint use in the Dammam Municipality of the Kingdom of Saudi Arabia, based on the premise that an increase in seat belt use would significantly reduce personal injury in traffic crashes. It was expected that local data would help identify intervention strategies necessary to improve seat belt use in the region.

Methods: The research involved 2 methodologies. First, 1,389 face-to-face interviews were conducted with male and female adults in regional shopping plazas regarding their own and their children's restraint use in their vehicles and reasons for these attitudes and beliefs. Second, 2 on-road observation studies of adult and child restraint use were conducted by trained observers. Occupants of approximately 5,000 passenger vehicles were observed while stopped at representative signalized traffic intersections.

Results: The findings showed front seat belt use rates of between 43 and 47% for drivers and 26 to 30% for front seat passengers; rear seat belt use rates were lower. While there seemed to be some knowledge about the purpose and reasons for restraining both adults and children in suitable restraints, this failed to be confirmed in the on-road observations.

Conclusions: Reasons for these rates and findings are discussed fully, and recommendations for improving seat belt use in the Dammam Municipality are included.     

Multiwell Technique of Saline and Nonsaline Groundwater Pumping from Coastal Aquifers

In this article, the authors explore their recent study, which introduces the concept of extracting saline water and fresh water simultaneously from groundwater aquifers to produce water that is suitable for irrigation. To achieve these results, multiwell modeling concepts are used to exploit both the saline and nonsaline aquifer domains from geologic formations where a freshwater aquifer domain is either underlain or overlain by a saline aquifer domain. The water from these domains are either mixed to an acceptable salinity level after independent withdrawal from separate, saline or nonsaline domains present within the same aquifer, or mixed from the domains to achieve acceptable levels of salinity before withdrawal.     

Mitigating Global Warming Potentials of Methane and Nitrous Oxide Gases from Rice Paddies under different irrigation regimes

A field experiment was conducted in Bangladesh Agricultural University Farm to investigate the mitigating effects of soil amendments such as calcium carbide, calcium silicate, phosphogypsum, and biochar with urea fertilizer on global warming potentials (GWPs) of methane (CH₄) and nitrous oxide (N₂O) gases during rice cultivation under continuous and intermittent irrigations. Among the amendments phosphogypsum and silicate fertilizer, being potential source of electron acceptors, decreased maximum level of seasonal CH₄ flux by 25–27 % and 32–38 % in continuous and intermittent irrigations, respectively. Biochar and calcium carbide amendments, acting as nitrification inhibitors, decreased N₂O emissions by 36–40 % and 26–30 % under continuous and intermittent irrigations, respectively. The total GWP of CH₄ and N₂O gases were decreased by 7–27 % and 6–34 % with calcium carbide, phosphogypsum, and silicate fertilizer amendments under continuous and intermittent irrigations, respectively. However, biochar amendments increased overall GWP of CH₄ and N₂O gases.     

Physicochemical factors and sources of particulate matter at residential urban environment in Kuala Lumpur

Long-term measurements (2004–2011) of PM₁₀ (particulate matter with an aerodynamic diameter <10 μm) and trace gases (carbon monoxide [CO], ozone [O₃], nitrogen oxide [NO], oxides of nitrogen [NO_x], nitrogen dioxide [NO₂], sulfur dioxide [SO₂], methane [CH₄], nonmethane hydrocarbon [NMHC]) have been conducted to study the effect of physicochemical factors on the PM₁₀ concentration. In addition, this study includes source apportionment of PM₁₀ in Kuala Lumpur urban environment. An advanced principal component analysis (PCA) technique coupled with absolute principal component scores (APCS) and multiple linear regression (MLR) has been applied. The average annual concentration of PM₁₀ for 8 yr is 51.3 ± 25.8 μg m^?3, which exceeds the Recommended Malaysian Air Quality Guideline (RMAQG) and international guideline values. Detail analysis shows the dependency of PM₁₀ on the linear changes of the motor vehicles in use and the amount of biomass burning, particularly from Sumatra, Indonesia, during southwesterly monsoon. The main sources of PM₁₀ identified by PCA-APCS-MLR are traffic combustion (28%), ozone coupled with meteorological factors (20%), and windblown particles (1%). However, the apportionment procedure left 28.0 μg m^?3, that is, 51% of PM₁₀ undetermined.

Implications: Air quality is always a top concern around the globe. Especially in the South Asian regions, measures are not yet sufficient; as revealed in our studies, the concentrations of particulate matters exceed the tolerable limits. Long-term data analysis and characterization of particular matters and their sources will aid the policy makers and the concerned authority to adapt measures and policies according to the circumstances. Additionally, similar intensive studies will give insight about future implications of air quality management.     

Profile of PAH in the Exhaust of Gasoline Driven Vehicles in Delhi

A preliminary study to determine the profile of PAHs in the exhaust of gasoline vehicles in Delhi was conducted. Three different types of vehicles (cars, autorickshaws and scooters) were selected with different age groups for sampling purpose. The concentration of Total PAHs (Σ₁₂PAHs) was found to be 27.27 ± 2.27, 28.61 ± 3.70 and 29.81 ± 3.57 mg/g in the exhaust of cars, auto- rickshaws (three wheelers) and two wheelers, respectively. The levels of PAHs were found to be high in scooter exhaust as compared to that of cars and autorickshaws. The total PAHs concentration in the present study was found to be higher as compared to other studies. Such a high concentration could be attributed to different parameters like the age of the vehicles, driving conditions, the fuel quality and the emission standards.     

Profile of PAHs in the Diesel Vehicle Exhaust in Delhi

A preliminary study to determine the profile of PAHs in the exhaust of diesel vehicles plying on Delhi roads was conducted. Two different types of diesel vehicles (buses and trucks) with different age groups were selected for sampling purpose. The concentration of Total PAHs (₁₂PAHs) was found to be 50.76 ± 6.62 and 57.72 ± 4.15 mg/g in the exhaust of buses and trucks, respectively. The levels of PAHs were found to be high in trucks as compared to that of buses. The total PAHs concentration in the present study was found to be higher as compared to other studies. Such a high concentration could be attributed to different parameters like the age of the vehicles, driving conditions, the fuel quality and the emission standards.