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This study was designed to investigate selected road-dust associated heavy metals, their relations with natural and anthropogenic sources, and potential human and environmental health risks. For this purpose, 42 and 36 road-dusts samples were collected from Jalalabad and Kabul cities (Afghanistan), respectively. The following elements were found in descending concentrations: Mn, Zn, Pb, Ni, Cu, Cr, Co, and Cd in Jalalabad; and Mn, Zn, Ni, Cu, Cr, Pb, Co, and Cd in Kabul. Except for Ni, all the elemental contents were less than the Canadian permissible limits in residential/parkland soils. Principle Component Analysis and enrichment of Cd, Cu, Ni, Pb, and Zn pointed to anthropogenic sources, whereas Co, Cr, and Mn indicated crustal inputs. Broadly, Cd monomial risk index ([Formula: see text]) was considerable; however, one site each in both cities showed high risk ([Formula: see text] ≥ 350). The potential ecological risk (RI) is mostly low; however, at some sites, the risk was considerable. Ingestion appeared to be the main exposure route (99%) for heavy metals and contributed > 90% to noncancerous (all residents), as well as 92% (children) and 75-89% (adults) cancerous risks. The noncancerous risks of all metals and their integrated risks for all residents were within acceptable levels. Moreover, potential cancer risks in children from Ni and Cr were slightly higher than the US-EPA safe levels but were within acceptable levels for adults. This study found higher risks to children and therefore recommends proper management and ways to control metals pollution load in these areas to decrease human health and RIs.

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The urban areas of many low-income countries must balance a rising demand for pit latrines for household sanitation provision against limitations in space, resulting in a need for pit latrine emptying services. This study was undertaken in the peri-urban neighborhood of Area 1B in the city of Mzuzu, Malawi, to examine the characteristics of household pit latrines for designing and selecting pit latrine emptying tools. We used 150 structured household surveys and field observations. From this, a subset was selected and 30 manual cone penetrometer tests were conducted at full latrines.Chemical oxygen demand analysis was also performed for 14 pit latrines. The results indicated that in addition to serving as a disposal for fecal matter, 90% of households also used pit latrines for domestic waste. Only 10% of the studied pit latrines were lined. The filling rate in the study area is calculated to be about three years, and no respondents reported previous emptying. It is suggested pit latrine emptying technology development focuses on a maximum tool diameter of 10 cm to fit through the keyhole (squat hole) and height of 146 cm to fit inside the superstructure, as well as supporting unlined pits and the ability to pump trash.

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Many people around the globe prefer bottled water especially in developing countries, where tap water is not drinkable. This study investigated the quality of bottled drinking water sold in Lilongwe city, Malawi. Compliance with Malawi Standards (MS) 560 (2004) for natural mineral water, MS 699 (2004) for bottled water and the World Health Organisation guidelines for drinking water were examined. Bottled water from different 12 brands was purchased from local stores and analysed for its pH, total dissolved solids (TDS), EC, turbidity, Ca, Mg, Na, K, Fe, NO3−, Cl−, F−, SO42−, hardness, alkalinity, and Escherichia coli. A Hierarchical Cluster Analysis (HCA) resulted in two clusters in which most of the brands (92%, n = 12) belonged to one group. The two clusters and significant differences (ANOVA p < 0.05) in chemical compositions among the brands were attributed to the variations in the water source and the treatment processes. The results showed that 10 brands did not comply with the MS 699 (2004) turbidity standard (1 NTU) and the pH of one of the brands was below the minimum MS 699 (2004) standard of 6.50. This research showed that 12 brands had bottle labelling errors and discrepancies in chemical composition. The article highlighted the need for a strict inspection from the responsible governmental ministry to improve water quality and to adjust water bottles’ labels according to water characteristics.