Breast cancer (BC) is becoming one of the most prevalent non-infectious disease in low and middle income countries. The steady rise of BC incidence may be related to the different risk factors. Among many, rampant presence of environmental pollutants might be one of the risk factors. Therefore, the aim of this study is to investigate exposure to organochlorine pesticides as a risk factor to breast cancer. A case-control study design was employed among breast cancer patients and non-breast cancer individuals (controls). Blood samples were collected from 100 study participants (50 cases and 50 controls) followed by serum separation, extraction and cleanup using standard analytical procdures. The findings revealed that ten organochlorine pesticides were detected in the serum of the study participants. From the detected organochlorine pesticides, heptachlor was observed at higher concentration for breast cancer patients (6.90±4.37 μg/L) and controls (9.15±3.84 μg/L). Mean serum level of p,p’-DDE, p,p’-DDT, heptachlor, gamma-chlordane, endosulfan, and dibutyl-chlorendate were significantly higher in the serum of breast cancer patients than the controls. From the studied pesticides, p,p’-DDT and gamma-chlordane are significant predictors for BC, while, others are equivocal. A unit increment of the concentration of p,p’-DDT (AOR; 2.03, 95% CI: 1.041–3.969) increased the odds of developing breast cancer by two, while for gamma-chlordane (AOR;3.12, 95% CI; 1.186–8.203) by three. Our study results suggesting that, organochlorines are a risk factors for breast cancer in Ethiopia. Decreasing exposure to such organochlorines might have a significant public health relevance in reducing non-communicable chronic illnesses. Besides, continues monitoring of persistent organic pollutants using body biomarkers is important for disease prevention and device mitigation measures.

Freeze desalination, i.e., desalination of water by freezing it, may be an option to treat polluted water at individual household level. Taking into account the widespread fluoride contamination of Ethiopian water resources and with the reason that most households in semi-urban and urban areas do have easier accessibility of refrigerators, this study aimed to investigate the defluoridation capacity of freeze desalination and its energy consumption for different water sources. For this purpose, synthetic solutions that emulate the major ion compositions of natural waters (hereafter called simulated water), tap water, and double-distilled water to which variable concentrations of fluoride ions were added were evaluated using home-use insulated refrigerator (BEKO, RRN 2650). The effects of conditions such as initial fluoride concentration, multi-ion existence, fraction of ice frozen, volume of the container, and freezing duration were evaluated in relation to the produced ice quality. It was found that nearly 48% and 62% removal of fluoride were achieved from tap water spiked with 10 mg/L F − and 10 mg/L F − aqueous solutions, respectively, with a total water recovery of 85 to 90%. The energy consumption predicted to produce the ice from tap water spiked with 10 mg/L F − and double-distilled water alone was found to be 93.9 and 91.8 kJ/L, respectively. The results showed that freeze desalination can be a potential technique for fluoride removal from water to be used as drinking water at household level in semi-urban and urban areas as well as in colder regions.

No abstract

Surface sediment samples were collected from different streams of Awetu Watershed in southwestern Ethiopia. Sediment samples were analyzed for As, Cd, Cr, Pb, and Hg levels using inductively coupled plasma optical emission spectrometry. The heavy metal concentration ranged from 183.60 to 1,102.80 mg/kg for As (mean 623.32 ± 291.65 mg/kg), 4.40–303.20 mg/kg for Cd (151.09 ± 111.5 mg/kg), 149.20–807.20 mg/kg for Cr (375 ± 212.03 mg/kg), 485.60–3,748.80 mg/kg for Pb (2005.94 ± 954.99 mg/kg) and 3.6–5.6 mg/kg for Hg (4.64 ± 0.59 mg/kg). The mean heavy metal concentration in the streams followed the decreasing order of Pb > As > Cr > Cd > Hg. As, Cr and Pb are detected at high concentrations with values of 623.32, 375.00, and 2,005.94 mg/kg respectively. A low level of heavy concentration (3.6 mg/kg) was recorded for Hg. The contamination factor (CF) of all the studied heavy metals ranged from a low degree (CF < 1) to a very high degree (CF ≤ 6). Mainly, Dololo and Kito streams show a very high degree of contamination (CF ≤ 6) than Awetu and Boye streams. Specifically, As, Cd and Cr in the Dololo and Kito streams have significantly elevated concentrations than others. Geo-accumulation index (Igeo) shows low to moderate contamination level with As, Pb, and Hg; uncontaminated to heavily contaminated by Cr; and moderate to extreme contamination by Cd. Untreated solid waste, garages and farmlands were sources of contamination. Streams receiving wastewater effluents from teaching institutions had higher heavy metal concentrations. Dumping of electronic wastes and car washing discharges also identified as another source of pollution.

No abstract