Search

Reservoirs and artificial channels are vital sources of water for irrigated areas in arid and semi-arid regions. As such, monitoring the radioecological state of these water bodies is crucial for public health and safety. In this study, we aimed to evaluate the radioecological condition of the Sobirsoy reservoir and surrounding areas. We used gamma-spectrometry to measure natural and anthropogenic radionuclides, and coal sorbents to measure radon flux density on the ground surface. Based on our findings, we conducted a radiological risk assessment and compiled an exposure dose map of the study area. The results showed that the degree of radioactive danger to people in populated areas is within safe limits. Overall, our study provides important information for policymakers and stakeholders to make informed decisions regarding the management and safety of the Sobirsoy reservoir and its surroundings. [ABSTRACT FROM AUTHOR]

Pollution of sediments by metals is a global issue, with developing countries like Nigeria, having its large PORTION. Niger River, the most valued river in Nigeria, is under serious anthropogenic perturbations with no measures to save the river by concerned authorities. Samplings were conducted at 12 designated stations of the lower reaches of the river within the southern region of Nigeria. The elements (As, Fe, Cu, Pb, Cd, Zn and Hg) were analysed using atomic absorption spectrophotometer. The average levels of As, Fe, Cu, Pb, Cd, Zn and Hg in the river sediments were 12, 115, 18, 11, 0.71, 36 and 0.59 mg/kg, respectively. Certain indices, including the enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI) and contamination factor (CF), were used to assess the ecological risk posed by metals in sediment. Cadmium in five locations (SP4− SP8) and Hg for sites SP4 and SP5, had their Igeo values above 1.0, which implies that these stations were moderately polluted. The EF values for Cd, Hg and As were above 1.5 (EF > 1.5) in sites SP4 and SP5 especially in the dry season, indicating strong enrichment of these elements in sediment to anthropogenic influences. Potential ecological risks of heavy metals in sediment showed weak to very high threat which implies that the condition is much frightening to the biota and inhabitants in the vicinity of the river as well. [ABSTRACT FROM AUTHOR]

Heavy metal enrichment in road dust has resulted from intensive anthropogenic activity, particularly urbanization, industrial activities and traffic emission, posing a hazard to urban ecosystems and human health. To promote optimal road dust management in urban environments, it is necessary to assess the possible ecological and health impact of toxic elements in road dust. In a heavily populated megacity like Dhaka, Bangladesh, large-scale risk assessments of contamination in road dust with heavy metals are limited. The present study aims at presenting a concentration of twenty-five metals in road dust (Na, K, Cs, Rb, Mg, Ca, Sr, Ba, Al, Zn, Cd, Pb, As, Sb, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr and W) in Dhaka megacity. We used a critical source-based positive matrix factorization model, source-oriented potential ecological risks and health risks. Out of the studied metals, Na, Ca, Zn, Cd, Cu, Zr and W exceeded the shale value. About 73%, 48%, 29% and 32% of sampling sites showed a higher level of pollution based on PLI, NIPI, PER and NIRI, respectively. PMF model identified that Cd (85.3%), Cr (62.4%), Ni (58.2%), Zn (81.8%) and Mn (65.9%) in road dust were primarily attributed to traffic emission, fuel combustion, metal processing, transport sources and natural sources, respectively. Fuel combustion and metal processing posed considerable and high risks based on modified potential ecological risk and NIRI. Based on health hazards, traffic emission posed a high cancer risk in adult males (29%), whereas transport sources contributed to females (21%) and children (23%). [ABSTRACT FROM AUTHOR]

An effective toxicological assessment of soil-metal bioavailability and plant translocation processes is needed in view of the growing negative impact of trace element pollution on the terrestrial environment and human health. This study was conducted to assess the toxicological processes that regulate the plants' trace element absorption into their tissues, the suitability for human use, the potential sources of trace elements, and the risk to human health, using an integrated research methodology. Soils and sweet potato plants were collected from agricultural fields near the tannery waste disposal sites of Dhaka City, Bangladesh and inductively coupled plasma mass spectrometers (ICP-MS) were used to analyze the essential and toxic elements. The mean concentrations of total elements in soil followed the descending order of Fe > Zn > Mn > Cr > Ni > Pb > Cu > As > Cd and in plant Fe > Zn > Cu > Cr > Ni > Mn > Pb > As > Cd. In the edible tissues of sweet potato, the concentrations of essential and toxic elements exceeded the maximum permissible levels, indicating not safe for human consumption. The translocation factor (TF) revealed that studied elements are more accumulated in the leaves than tubers. The enrichment factor revealed minimal to very high enrichment of essential and toxic elements in the plant parts while the contamination factor showed low to very high contamination. Considering the health risk of toxic elements from plant samples, As and Pb caused non-cancer and cancer risk on human health. However, the present results suggested that regular monitoring of these essential and toxic elements in soil and plants as well as other food materials around the abandoned tannery waste disposal sites are necessary to prevent excessive build-up of these elements in the food chain. [ABSTRACT FROM AUTHOR]