Lead contamination in surface soil on roads from used lead–acid battery recycling in Dong Mai,Northern Vietnam

Used lead–acid battery (ULAB) recycling has caused numerous health and environmental issues in developing countries. Surface soil pollution from ULAB recycling activities has been linked with elevated levels of lead in human blood. We measured surface soil lead in and surrounding the ULAB recycling village of Hung Yen in northern Vietnam in 2011, 2013, and 2014. The data were analyzed statistically and discussed with respect to distance from the contamination source, year of measurement, contamination pathway, and countermeasures against the contamination. Transportation routes from the smelter or collection site displayed the greatest concentration of surface soil lead (median 6400–10,000 mg/kg). Surface soil lead decreased significantly with distance along the road from the ULAB recycling site, although such a decrease was not observed for rice fields, agricultural roads, or garden soil. Re-suspension and adherence by traffic were identified as key pollution pathways. Distance from the source, covering of the surface of roads, construction of walls, and position relative to the source were shown to be the most effective factors in the reduction of surface soil lead pollution. Application of a combination of these measures should result in improvement in the health of residents.     

Plastic waste as a valuable resource: strategy to remove heavy metals from wastewater in bench scale application

Environmental Science and Pollution Research - Single-use plastic waste is gradually considered a potential material for circular economy. Ion exchange resin obtained from polystyrene waste by...     

Assessment of total concentrations of heavy metals in industrial sludges from the North of Vietnam and their potential impact on the ecosystem

Environmental Science and Pollution Research - Industrial sludges from wastewater treatment plants of industrial parks and a drinking water treatment plant in northern Vietnam were investigated in...     

The protective effect of green space on heat-related respiratory hospitalization among children under 5 years of age in Hanoi,Vietnam

Environmental Science and Pollution Research - Combined effects of global warming and rapid urbanization replace green spaces with urban facilities. Children in urban areas are at a higher risk of...     

Comprehensive temperature monitoring in an in-vessel forced-aeration static-bed composting process

Comprehensive temperature monitoring was done in an in-vessel forced-aeration static-bed composting process using sewage sludge. The three layers that divided the compost pile horizontally showed different temperature distributions. The temperature of the top layer appeared not to be influenced by the ambient temperature. The temperature of the center area of the top layer was taken to be the representative temperature for evaluating composting start-up performance. The temperature of the bottom layer was strongly influenced by the ambient temperature, and the temperature of the center area of the bottom layer was taken to be the representative temperature for pathogen control as it was the minimum temperature in the reactor. Composting start-up performance was influenced by several factors when the ambient temperature was either below or above 20°C. When the ambient temperature was below 20°C, the time taken to reach 65°C (T ₆₅) was influenced by the temperature of inflowing air, but when the temperature was higher than 20°C, it was influenced by the ratio of sewage sludge to seed compost (F/S). T ₆₅ was least when F/S was 1–2. Received: January 9, 2001 / Accepted: October 10, 2001     

Sustainable livelihoods development by utilization of geomorphological resources in the Bai Tu Long Bay,Quang Ninh Province,Vietnam

Located in the humid tropical zone and endowed with carbonate sedimentary formations, Vietnam has unique karst landscapes where caves, limestone, and dolines are common. If well managed, these are valuable geomorphological resources for a sustainable socio-economic development. Although publications on sustainable livelihoods associated with conserving biodiversity and local culture are plentiful, there is still a lack of studies linking livelihood quality with the conservation of geomorphological resources, in particular in karst areas. This study assesses the geomorphological resources in Vietnam’s Bai Tu Long Bay and studies the relationship between livelihood and these resources. The current research area Bai Tu Long Bay is adjacent to the natural World Heritage site of Ha Long Bay in the Vietnamese part of the Gulf of Tonkin. Bai Tu Long is characterized by a karst landscape, which is at the same time similar but also different from Ha Long Bay. A field survey and interviews with 153 households allowed assessing people’s perception of the value of the geomorphological resources and their importance for local income. The results show that Bai Tu Long Bay has abundant, diverse, and unique geomorphological resources, which are valuable for tourism development. However, the local people are unaware of these values likely because they have no direct benefit from them. Further a sustainable development strategy for Bai Tu Long Bay is recommended. The outcome is a proposal for tourism initiatives aiming at realizing more sustainability in the area.     

Spatial and temporal variations of PAHs in surface sediments of estuarine and coast of CanGio wetland,Vietnam

Surface sediments from estuarine and coast of CanGio wetland (CGW) of Hochiminh City, Vietnam, were investigated to identify the spatial and temporal variations of polycyclic aromatic hydrocarbons (PAHs). The total PAHs showed wide variation but similar to patterns observed (F?=?0.901, p?=?0.46) in LongTau (31?±?77 ng/g dry weight, n?=?13), SoaiRap (53?±?81, n?=?4), ThiVai (60?±?62, n?=?10) estuaries, and coastal areas (112?±?211, n?=?9). A decreasing trend in the wet season (F?=?8.8, p?=?0.01) reflected that inland sources such as wastewater discharged and atmospherically transported contaminants contributed to PAHs in sediments. The risk posed by the PAHs in the coastal and estuarine areas of CGW is still negligible. The present study provides baseline data, which can be used for regular monitoring and future strategy of environmental protection for the study area.

     

The status and distribution of PCBs along the coast of Vietnam

Environmental Geochemistry and Health - Polychlorinated biphenyls (PCBs), well-known as an important scientific achievement, are now considered as one of the most persistent organic pollutants...     

Nitrous oxide generation in denitrifying phosphorus removal process: main causes and control measures

Despite the many benefits of denitrifying phosphorus removal process, the significant generation of nitrous oxide (N₂O), a potent greenhouse gas, remains a problem for this innovative and promising process. To better understand and more effectively control N₂O generation in denitrifying phosphorus removal process, batch experiments were carried out to investigate the main causes of N₂O generation, based on which the control measures were subsequently proposed. The results showed that N₂O generation accounted for 0.41 % of the total nitrogen removal in denitrifying phosphorus removal process, whereas, in contrast, almost no N₂O was generated in conventional denitrification process. It was further demonstrated that the weak competition of N₂O reductase for electrons and the high nitrite accumulation were the two main causes for N₂O generation, evidenced by N₂O production and reduction rates under different conditions. Accordingly, the reduction of N₂O generation was successfully achieved via two control measures: (1) the use of continuous nitrate addition reducing N₂O generation by around 91.4 % and (2) the use of propionate as the carbon source reducing N₂O generation by around 69.8 %.