Concentration and Health Implication of Heavy Metals in Drinking Water from Urban Areas of Tigray Region, Northern Ethiopia

The study was undertaken to assess the status of drinking water quality in the urban areas of the Tigray region, northern Ethiopia. A total of 106 drinking water samples were collected from 16 densely populated urban areas of the region, viz.: Alamata, Korem, Maichew, Adigudom, Abyi-Adi, Hagereselam, Zalambessa, Adigrat, Edagahamus, Firewoini, Wukro, Mekelle, Indaselassie, Axum, Adwa, and Enticho. All the samples were analyzed for six physicochemical parameters such as temperature, conductivity, total dissolved solids (TDS), salinity, pH, and turbidity and ten heavy metals,viz., As, Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, and Zn using standard procedures. The results were compared with other national and international standards. Among the analyzed samples, regarding physicochemical parameters, 84.01 % for electrical conductivity, 47.17 % for TDS and 31.13% for turbidity show concentrations higher than the WHO (2008) recommended values. More than 93.4% of the samples were within the United States Environmental Protection Agency (US EPA) admissible pH limit (6.5-8.5) and all the samples analyzed were within the EU (1998) admissible pH limit (6.5-9.5). All samples contain manganese and copper within the WHO (2008) maximum admissible limit, but arsenic (40.3 %), cadmium (7.46 %), chromium (64.18 %), iron (37.31 %), nickel (7 %), and lead (29.85 %) crossed the maximum admissible and desirable limits recommended by WHO (2008). The maximum admissible limit of cobalt in drinking water is not mentioned by WHO, but all the samples analyzed were found to comply the New Zealand (1000 μg/L) and US EPA (100 μg/L) maximum admissible limits. Although no guideline is set by WHO (2008) for Zinc level in drinking water, of the samples analyzed, 94.02% comply the New Zealand standard and 97.01% comply all the maximum admissible limits referred in the present study. In general, the results of the present study have shown that some of the physico-chemical parameters have shown values higher than the WHO (2008) recommended maximum admissible limits. This is an indication of pollution hazards and weak drinking water treatment practices in the areas, which in turn have important human health implications. This study, therefore, recommends the government and other responsible authorities to take appropriate corrective measures. Key words: Drinking water quality, Heavy metals, Maximum admissible limit, World health organization, Tigra

Traditional knowledge of medicinal plants in Gindeberet district Western Ethiopia. South African

Abstract Ethiopia, is a country characterized by a wide range of climate and ecological conditions, possesses enormous diversity of fauna and flora. Semi-structured interviewees, observation and guided field walks with informants were employed to obtain ethnobotanical data in Gindeberet district, western Ethiopia. A total of 120 informants (84 males and 36 females) were selected purposefully from six sub districts. A total of 26 species of medicinal plants were collected and identified for treating 36 human ailments. The medicinal plant preparations were administered through oral, dermal and nasal routes. Oral application (33 preparations, 67.3%) was the highest and most commonly used route of application followed by dermal application (15 preparations, 30.6%). The most commonly used plant parts for herbal preparations were leaves (28%) and roots (28%) followed by barks (14%) and fruits (14%). Gindeberet district is rich in its medicinal plant composition and the associated indigenous knowledge. Evaluation of the medicinal plants for their efficacy and possible toxicity would be very important

Molecular anatomy of the cytoplasmic domain of bovine growth hormone receptor, a quantitative trait locus

Quantitative trait loci (QTL) studies have indicated growth hormone receptor (GHR) as a candidate gene affecting cattle milk yield and composition. In order to characterize genetic variation at GHR in cattle, we studied European and East African breeds with different histories of selection, and Bos grunniens, Ovis aries, Sus scrofa, Bison bison and Rangifer tarandus as references. We sequenced most of the cytoplasmic domain (900 bp of exon 10), 89 bp of exon 8, including the putative causative mutation for the QTL effect, and 390 bp of intron 8 for comparison. In the cytoplasmic domain, seven synonymous and seven non-synonymous single nucleotide polymorphisms (SNP) were identified in cattle. Three non-synonymous SNPs were found in sheep and one synonymous SNP in yak, while other studied species were monomorphic. Three major haplotypes were observed, one unique to African breeds, one unique to European breeds and one shared. Bison and yak haplotypes are derivatives of the European haplotype lineage. Most of the exon 10 non-synonymous cattle SNPs appear at phylogenetically highly conserved sites. The polymorphisms in exon 10 cluster around a ruminant-specific tyrosine residue, suggesting that this site may act as an additional signalling domain of GHR in ruminants. Alternative explanations for the persistent polymorphism include balancing selection, hitch-hiking, pleiotropic or sexually antagonistic fitness effects or relaxed functional constraints

Molecular anatomy of the cytoplasmic domain of bovine growth hormone receptor, a quantitative trait locus

Quantitative trait loci (QTL) studies have indicated growth hormone receptor (GHR) as a candidate gene affecting cattle milk yield and composition. In order to characterize genetic variation at GHR in cattle, we studied European and East African breeds with different histories of selection, and Bos grunniens, Ovis aries, Sus scrofa, Bison bison and Rangifer tarandus as references. We sequenced most of the cytoplasmic domain (900 bp of exon 10), 89 bp of exon 8, including the putative causative mutation for the QTL effect, and 390 bp of intron 8 for comparison. In the cytoplasmic domain, seven synonymous and seven non-synonymous single nucleotide polymorphisms (SNP) were identified in cattle. Three non-synonymous SNPs were found in sheep and one synonymous SNP in yak, while other studied species were monomorphic. Three major haplotypes were observed, one unique to African breeds, one unique to European breeds and one shared. Bison and yak haplotypes are derivatives of the European haplotype lineage. Most of the exon 10 non-synonymous cattle SNPs appear at phylogenetically highly conserved sites. The polymorphisms in exon 10 cluster around a ruminant-specific tyrosine residue, suggesting that this site may act as an additional signalling domain of GHR in ruminants. Alternative explanations for the persistent polymorphism include balancing selection, hitch-hiking, pleiotropic or sexually antagonistic fitness effects or relaxed functional constraints