High Bacterial Contamination Research Articles

Effects of inoculum size, light intensity, and dose of anaerobic digestion centrate on growth and productivity of Chlorella and Scenedesmus microalgae and their poly-culture in primary and secondary wastewater

Scale-up of microalgal biofuel technology is challenged by availability of nitrogen and phosphorus fertilizers and the potential negative impact vast increases in chemical fertilizer demand would have on conventional agriculture. The current study investigated replacement of chemical fertilizers with nutrients sourced from primary and secondary wastewater effluents and anaerobic digestion centrate (ADC). Although primary wastewater effluent possessed a high optical density (OD) and bacterial contamination, it was a superior growth medium for microalgal cultivation than nutrient-scarce secondary effluent. Chlorella sorokiniana and Scenedesmus acutus f. alternans showed higher growth rates, productivities, and robustness than other species or poly-cultures of five species. While supplementing with 5–10% nutrient-rich ADC increased wastewater OD, it also enhanced microalgal growth rates from 0.2–0.3d−1 to 0.7–0.9d−1 and biomass productivity from 10 to 20mgL−1d to 40–60mgL−1d with greater improvements for secondary effluents. Supplementation with ADC also increased nutrient concentrations (N, P, Mn, B, Zn, Co by >100% and S, Mg, Ca, Mo by 20–60%) and improved the nitrogen to phosphorus (N:P) ratio. Higher ADC dose of 20% inhibited microalgae growth potentially due to ammonia toxicity. Elevation of inoculum doses and light intensity increased final biomass density and productivity, with intensities <140μmolphotonm−2s−1 limiting algal growth rates. Inoculum doses of ≥2.5×105cellmL−1 were most favorable for cultivation of all tested microalgae and for FAME content and composition for a newly characterized strain of Chlorella sorokiniana. Overall, ADC represents an economical fertilizer substitute providing various nutrients needed for microalgal growth and enhancing biofuel sustainability.

Bacterial and Fungal Contamination of Elevator Buttons in University Schools of Isfahan University of Medical Sciences, Isfahan, Iran

Background: The control of microorganisms in industrial and residential environments is the main concern regarding the spread of infectious diseases. Objectives: The current study aimed to isolate the bacteria and fungi from elevator buttons in the schools of Isfahan University of Medical Sciences, Isfahan, Iran. Methods: The study was a across sectional research. Samples were taken from elevator buttons in the schools of Isfahan University of Medical Sciences. Detection of the type of bacteria and fungi was done in blood agar, eosin methylene blue (EMB) agar and sabouraud dextrose agar according to the standard microbiological methods. Finally, Gram-positive and Gram-negative bacteria and fungi were identified. Results: This study was conducted on 35 buttons from seven elevators in Isfahan University of Medical Sciences schools. All the samples showed bacterial contamination (100%) with the kind of Gram-positive and -negative bacteria and all of them had Staphylococcus and Enterobacter species contamination. Schools of medicine, dentistry, management and medical information sciences had the highest bacterial contamination. On the other hand, fungal contamination was not detected in the samples. Conclusions: The study showed that elevator buttons could lead to transmission of pathogenic bacteria. It is necessary to clean and disinfect elevator buttons daily, especially in departments with high contamination potential such as laboratories, particularly in biological laboratories and pilot plant rooms.

Bacterial and Fungal Contamination of Elevator Buttons in University Schools of Isfahan University of Medical Sciences, Isfahan, Iran

Background: The control of microorganisms in industrial and residential environments is the main concern regarding the spread of infectious diseases. Objectives: The current study aimed to isolate the bacteria and fungi from elevator buttons in the schools of Isfahan University of Medical Sciences, Isfahan, Iran. Methods: The study was a across sectional research. Samples were taken from elevator buttons in the schools of Isfahan University of Medical Sciences. Detection of the type of bacteria and fungi was done in blood agar, eosin methylene blue (EMB) agar and sabouraud dextrose agar according to the standard microbiological methods. Finally, Gram-positive and Gram-negative bacteria and fungi were identified. Results: This study was conducted on 35 buttons from seven elevators in Isfahan University of Medical Sciences schools. All the samples showed bacterial contamination (100%) with the kind of Gram-positive and -negative bacteria and all of them had Staphylococcus and Enterobacter species contamination. Schools of medicine, dentistry, management and medical information sciences had the highest bacterial contamination. On the other hand, fungal contamination was not detected in the samples. Conclusions: The study showed that elevator buttons could lead to transmission of pathogenic bacteria. It is necessary to clean and disinfect elevator buttons daily, especially in departments with high contamination potential such as laboratories, particularly in biological laboratories and pilot plant rooms.

Health risk assessment of heavy metals and bacterial contamination in drinking water sources: a case study of Malakand Agency, Pakistan.

Human beings are frequently exposed to pathogens and heavy metals through ingestion of contaminated drinking water throughout the world particularly in developing countries. The present study aimed to assess the quality of water used for drinking purposes in Malakand Agency, Pakistan. Water samples were collected from different sources (dug wells, bore wells, tube wells, springs, and hand pumps) and analyzed for different physico-chemical parameters and bacterial pathogens (fecal coliform bacteria) using standard methods, while heavy metals were analyzed using atomic absorption spectrophotometry (AAS-PEA-700). In the study area, 70 % of water sources were contaminated with F. coliform representing high bacterial contamination. The heavy metals, such as Cd (29 and 8 %), Ni (16 and 78 %), and Cr (7 %), exceeded their respective safe limits of WHO (2006) and Pak-EPA (2008), respectively, in water sources, while Pb (9 %) only exceeded from WHO safe limit. The risk assessment tools such as daily intake of metals (DIMs) and health risk indexes (HRIs) were used for health risk estimation and were observed in the order of Ni > Cr > Mn > Pb > Cd and Cd > Ni > Pb > Mn > Cr, respectively. The HRI values of heavy metals for both children and adults were <1, showing lack of potential health risk to the local inhabitants of the study area.

Identification of specific microorganisms in fresh squeezed street vended fruit juices

Introduction: In developing country like India, street foods such as salads and fresh cut fruits are widely consumed. Among all street foods, fruit juices are common beverages, consumed more because of higher consumer preference both in terms of taste and health. Moreover, there is a dearth of Indian studies on contamination of street vended fruit juices. Aim: To determine the pH and specific microorganisms in freshly squeezed street vended fruit juices. Materials and Methods: Four fruit juices i.e., Grapes, Sweet Lime, Pineapple and Sapota were chosen for the study. Juices were collected in summer season in months between April and June 2013. Ten samples of 50 ml each fruit juice was collected in sterile bottles from various street vendors of Dilshuknagar area of Hyderabad city. Transportation of samples to Food Toxicology laboratory, National Institute of Nutrition was done in the ice box and processing was done within 2–4 h. Results: All juices showed bacterial contamination except one sample of grape juice. Pineapple juice samples showed the high bacterial contamination with all samples positive for fecal coliforms and Shigella spp. (100%). Salmonella spp. was detected only in one sample of Sapota juice (10%). Significant difference among fruit juices for prevalence of microorganisms was seen only for Escherichia coli (P = 0.03) with least count in Grape juice (20%). Conclusion: Freshly squeezed street vended fruit juices were contaminated with pathogenic bacteria, which significantly attributed to public health problem.

WOUND HEALING AND CLINICAL IMPACT OF PRIMARY SUTURE IN SURGERY OF TUMORS OF SOFT TISSUE OF THE HEAD AND NECK

Analyzed the results of treatment of 584 patients operated on for soft tissue tumors of the head and neck with the elimination of the defect formed by directly comparing the edges of wounds by primary suture. Taking into account the level of the wound by M.I. Kuzin et al. (1977), the dynamics of clinical and laboratory results, morphological, biological research, local thermometry and vulnotenziometry. Statistical significance was estimated using the Student's t-test, Mann–Whitney U-test, and criteria χ2 and Fisher with certainty changes in p &lt; 0.05. Found that in the majority of patients kept the wound heals biologically programmed tissue reactions. At the same time, high bacterial contamination of integumentary tissues in the area of operations, especially against the background of the malignant tumor was a risk factor for the development of wound complications in 18 % of patients. The observed the oncological impact was characterized by the five-year survival at 90.6 ± 1.9 %. The 4.5 ± 1.9 % of patients had a direct link to death from malignant tumor.

Prosthetic Repair of the Abdominal Wall Using Light and Ultra-Light Synthetic and Titan-Containing Materials in High Bacterial Contamination (Experimental Study)

Prosthetic Repair of the Abdominal Wall Using Light and Ultra-Light Synthetic and Titan-Containing Materials in High Bacterial Contamination (Experimental Study)

Treatment of Platelet Products with Riboflavin and UV Light: Effectiveness Against High Titer Bacterial Contamination.

Contamination of platelet units by bacteria has long been acknowledged as a significant transfusion risk due to their post-donation storage conditions. Products are routinely stored at 22 °C on an agitating shaker, a condition that can promote bacterial growth. Although the total number of bacteria believed to be introduced into a platelet product is extremely low, these bacteria can multiply to a very high titer prior to transfusion, potentially resulting in serious adverse events. The aim of this study was to evaluate a riboflavin based pathogen reduction process against a panel of bacteria that have been identified as common contaminants of platelet products. This panel included the following organisms: S. epidermidis, S. aureus, S. mitis, S. pyogenes, S. marcescens, Y. enterocolitica, B. neotomae, B. cereus, E. coli, P. aeruginosa and K. pneumoniae. Each platelet unit was inoculated with a high bacterial load and samples were removed both before and after treatment. A colony forming assay, using an end point dilution scheme, was used to determine the pre-treatment and post-treatment bacterial titers. Log reduction was calculated by subtracting the post-treatment titer from the pre-treatment titer. The following log reductions were observed: S. epidermidis 4.7 log (99.998%), S. aureus 4.8 log (99.998%), S. mitis 3.7 log (99.98%), S. pyogenes 2.6 log (99.7%), S. marcescens 4.0 log (99.99%), Y. enterocolitica 3.3 log (99.95%), B. neotomae 5.4 log (99.9996%), B. cereus 2.6 log (99.7%), E. coli ≥5.4 log (99.9996%), P. aeruginosa 4.7 log (99.998%) and K. pneumoniae 2.8 log (99.8%). The results from this study suggest the process could help to lower the risk of severe adverse transfusion events associated with bacterial contamination.

Treatment of Platelet Products with Riboflavin and UV Light: Effectiveness Against High Titer Bacterial Contamination

Contamination of platelet units by bacteria has long been acknowledged as a significant transfusion risk due to their post-donation storage conditions. Products are routinely stored at 22 °C on an agitating shaker, a condition that can promote bacterial growth. Although the total number of bacteria believed to be introduced into a platelet product is extremely low, these bacteria can multiply to a very high titer prior to transfusion, potentially resulting in serious adverse events. The aim of this study was to evaluate a riboflavin based pathogen reduction process against a panel of bacteria that have been identified as common contaminants of platelet products. This panel included the following organisms: S. epidermidis, S. aureus, S. mitis, S. pyogenes, S. marcescens, Y. enterocolitica, B. neotomae, B. cereus, E. coli, P. aeruginosa and K. pneumoniae. Each platelet unit was inoculated with a high bacterial load and samples were removed both before and after treatment. A colony forming assay, using an end point dilution scheme, was used to determine the pre-treatment and post-treatment bacterial titers. Log reduction was calculated by subtracting the post-treatment titer from the pre-treatment titer. The following log reductions were observed: S. epidermidis 4.7 log (99.998%), S. aureus 4.8 log (99.998%), S. mitis 3.7 log (99.98%), S. pyogenes 2.6 log (99.7%), S. marcescens 4.0 log (99.99%), Y. enterocolitica 3.3 log (99.95%), B. neotomae 5.4 log (99.9996%), B. cereus 2.6 log (99.7%), E. coli ≥5.4 log (99.9996%), P. aeruginosa 4.7 log (99.998%) and K. pneumoniae 2.8 log (99.8%). The results from this study suggest the process could help to lower the risk of severe adverse transfusion events associated with bacterial contamination.

English

Garri as popularly known in Nigeria is a general food consumed by most people in Nigeria. It could be eaten by reconstituting it with hot water, stirred to form a thick paste and eaten with soup or stew. It could also be taken dried or mixed with cold water and sugar/milk, as a snack. As a part of check mating the public health risk associated with this general dependence of the population on garri, the bacteriological quality of garri sold in Owerri open market was examined with the aim of investigating the bacterial contamination of garri due to exposure in the market as well as establish the hygienic statue of garri taken as snacks by many Nigeria. To achieve this, a total of one hundred and ten (110) garri samples were collected from Eke-ukwu market, relief market, Eke-Mmegbu market, Orji market, IMSU gate market and some local garri processing factories within Oweri metropolis to serve as control. The samples were analyzed bacteriologically for viable heterotrophic bacteria and coliform bacteria counts on Nutrient and MacConkey agar respectively, using pour plate method. The mean value results from all the markets revealed high bacterial contamination, except from the factory. The resultant data were analyzed statistically using Chi-square to determine if there is a significant difference between the five markets. When calculated, the value of the five markets was 35.75 while the tabulated was 11.07. This implies that there was a significant difference between the five markets. Identified bacteria included: Staphylococcus aureus, Staphylococcus epidenmidis, Bacilus cerus, Escherichia coli and Klebsielia aerogenes. Isolation of these bacteria is a sign of danger, hence, Imo State government is advised to take measures such as making environmental sanitation a priority project in the state to save the lives of the citizens. Key words: Market, sample, snack, organism, contamination, Owerri.

Microbial air quality and bacterial surface contamination in ambulances during patient services.

We sought to assess microbial air quality and bacterial surface contamination on medical instruments and the surrounding areas among 30 ambulance runs during service. We performed a cross-sectional study of 106 air samples collected from 30 ambulances before patient services and 212 air samples collected during patient services to assess the bacterial and fungal counts at the two time points. Additionally, 226 surface swab samples were collected from medical instrument surfaces and the surrounding areas before and after ambulance runs. Groups or genus of isolated bacteria and fungi were preliminarily identified by Gram's stain and lactophenol cotton blue. Data were analyzed using descriptive statistics, t-test, and Pearson's correlation coefficient with a p-value of less than 0.050 considered significant. The mean and standard deviation of bacterial and fungal counts at the start of ambulance runs were 318±485cfu/m(3) and 522±581cfu/m(3), respectively. Bacterial counts during patient services were 468±607cfu/m(3) and fungal counts were 656±612cfu/m(3). Mean bacterial and fungal counts during patient services were significantly higher than those at the start of ambulance runs, p=0.005 and p=0.030, respectively. For surface contamination, the overall bacterial counts before and after patient services were 0.8±0.7cfu/cm(2) and 1.3±1.1cfu/cm(2), respectively (p<0.001). The predominant isolated bacteria and fungi were Staphylococcus spp. and Aspergillus spp., respectively. Additionally, there was a significantly positive correlation between bacterial (r=0.3, p<0.010) and fungal counts (r=0.2, p=0.020) in air samples and bacterial counts on medical instruments and allocated areas. This study revealed high microbial contamination (bacterial and fungal) in ambulance air during services and higher bacterial contamination on medical instrument surfaces and allocated areas after ambulance services compared to the start of ambulance runs. Additionally, bacterial and fungal counts in ambulance air showed a significantly positive correlation with the bacterial surface contamination on medical instruments and allocated areas. Further studies should be conducted to determine the optimal intervention to reduce microbial contamination in the ambulance environment.

Spatiotemporal distribution of the bacterial contamination of agricultural and domestic wastewater discharged to a drainage ditch (Sinaloa, Mexico)

The agricultural drainage water from the Sinaloa valley (Mexico) is often reused in agriculture and aquaculture before reaching coastal water bodies. Discharged water must be of good quality to maintain the health of ecosystems and prevent damage to the organisms that compose them. This research determined the occurrence of coliforms in a drainage ditch known as La Michoacana (Sinaloa) that receives contaminated water from agricultural and urban sources. A section of 3.6 km was studied during 2013 and samples were obtained monthly from five equidistant sampling sites. Each water sample was analyzed for total coliform (TC) and fecal coliform (FC) content, pH, salinity, temperature, and dissolved oxygen percentage (%DO). The sampling sites with the highest bacterial contamination were associated with direct discharges of domestic wastewater and those with the lowest to the output drain. The performance of this agricultural ditch decreased the concentration of coliforms, with median and average values of 96% and 87% for TC, and 98% and 85% for FC, respectively. The most common bacteria were Escherichia coli (67.7%), Kluyvera cryocrescens (10.2%), and Enterobacter agglomerans (6.3%). Coliform concentration was positively correlated with temperature and negatively with %DO. The ditch improved the microbiological quality of the water, demonstrating remediation activities in the system. Proper management and maintenance of agricultural drainage ditches would favorably impact the health and biodiversity, as well as the intensive aquaculture and agricultural activities of the Sinaloa valley.

Silver nanocluster-silica composite antibacterial coatings for materials to be used in mobile telephones

Antibacterial coatings containing different amount of metallic silver nanoclusters embedded in a silica matrix have been deposited by co-sputtering technique on several different polymers used in mobile telephones components such as: screens, covers, and microphone felts. Sputtering parameters have been varied to obtain different coating thickness and silver content, in order to meet antibacterial, aesthetic and functional requirements for each component. In particular, an antibacterial functionality has been obtained for screens, covers and felts without affecting their respective transparency, aesthetic and acoustic properties. The optimal parameters for each part have been used to obtain an antibacterial mobile telephone suitable for personnel operating in hospitals or other environments with potentially high bacterial contamination.

Study on bacteriological quality of Kunun aya (Tigernut juice) sold at Umaru Musa Yar’adua University (UMYU) campus, Katsina

The study was aimed at determining the Bacteriological quality of Kunun aya (Tigernut juice) which is one of the most regularly non-alcoholic drinks consumed within Umaru Musa Yar’adua University campus. Samples were collected and analyzed from different places at the University for the Enumeration of bacteria. Serial dilutions were carried out from the collected samples where a dilution factor of 10-5 was obtained for each sample. Total aerobic bacterial counts, total coliform counts and Salmonella-Shigella counts were determined from the samples using Pour Plate Technique. The results obtained shows high bacterial load as the total aerobic bacterial counts had a range of 2.2x104 - 1.4x106 cfu/ml. Total coliform counts had 8.2 x 102 - 6.1 x 104 cfu/ml while Salmonella-Shigella counts had 1.1 x 102 - 8.7 x 104 cfu/ml. The result shows high bacterial contamination of Kunun aya, which may be obtained from the poor hygienic preparation process. This could be the reason for its quick spoilage. Preserving the drink in very low temperature may reduce the chances for its early spoilage. DOI: http://dx.doi.org/10.3126/ije.v3i2.10518 International Journal of the Environment Vol.3(2) 2014: 87-97

Antibacterial activity of essential oils and their active components from Thai spices against foodborne pathogens

As the popularity of organic food especially fresh vegetables is increasing, it is a common practice to replace chemical fertilizers by manure which leads to high bacterial contamination. Some essential oils such as Thymus vulgaris (thyme) and Ocimum basilicum (basil) oils reduce spoilage flora and foodborne pathogens when used in washing water. This information prompted us to search for effective essential oils from Thai spices for vegetable washing products. Seven out of nine essential oils; fingerroot (Boesenbergia pandurata (Roxb.) Schltr.), galanga (Alpinia galanga (L.) Willd.), holy basil (Ocimum tenuiflorum L.), makrut leaf, makrut peel (Citrus hystrix DC.), sweet basil (O. basilicum L.), and turmeric (Curcuma longa L.) oils showed antibacterial activity. The active components were identified by thin layer chromatography (TLC) bioautography, preparative TLC, and gas chromatography-mass spectrometry. The results indicated that the active components were major components of the oils. The essential oils exhibited higher potency than their active components suggesting that the whole essential oils were more suitable than the pure compounds for product development.

Haemophilus influenzae as an airborne contamination in child day care centers

The aim of this study was to assess the exposure of children to airborne Haemophilus influenzae in day care centers. Air samples were taken using an Andersen impactor in 32 rooms designed for children stay. The concentrations of airborne bacteria were calculated as colony forming units (CFU) (growing on trypticase soy agar) per cubic meter of air (CFU/m(3)). The compositions of bioaerosol were determined on blood trypticase soy agar and Haemophilus selective agar. Isolated strains were identified using API NH strips and apiweb software. The antibiotic resistance of H influenzae strains was determined by the disk diffusion method. Compared with the proposed criteria for microbiologic quality of indoor air, the rooms were characterized by the very high bacterial contamination of the air. The prevailing component of bacterial aerosol was gram-positive cocci. Airborne H influenzae strains were found in 25% of the investigated rooms and were mostly classified as biotype II (33%). It may be accepted that the exposure to airborne H influenzae is typical of child day care centers in contrast to indoor environments with older population. Child day care center contribute to the expansion of H influenzae in human population via air. Generally, airborne H influenzae isolates from the investigated child day care centers were susceptible to older antibiotics such as ampicillin and amoxicillin-clavulanic acid.

Nearshore hydrodynamics as loading and forcing factors for Escherichia coli contamination at an embayed beach

Numerical simulations of the transport and fate of Escherichia coli were conducted at Chicago's 63rd Street Beach, an embayed beach that had the highest mean E. coli concentration among 23 similar Lake Michigan beaches during summer months of 2000–2005, in order to find the cause for the high bacterial contamination. The numerical model was based on the transport of E. coli by current circulation patterns in the embayment driven by longshore main currents and the loss of E. coli in the water column, taking settling as well as bacterial dark‐ and solar‐related decay into account. Two E. coli loading scenarios were considered: one from the open boundary north of the embayment and the other from the shallow water near the beachfront. Simulations showed that the embayed beach behaves as a sink for E. coli in that it generally receives E. coli more efficiently than it releases them. This is a result of the significantly different hydrodynamic forcing factors between the inside of the embayment and the main coastal flow outside. The settled E. coli inside the embayment can be a potential source of contamination during subsequent sediment resuspension events, suggesting that deposition‐resuspension cycles of E. coli have resulted in excessive bacterial contamination of beach water. A further hypothetical case with a breakwater shortened to half its original length, which was anticipated to enhance the current circulation in the embayment, showed a reduction in E. coli concentrations of nearly 20%.

Diversity of Bacteria Contaminants in Tissues of Fish Cultured in Organic Waste-Fertilized Ponds: Health Implications~!2009-10-15~!2010-02-16~!2010-06-17~!

Bacterial populations contaminating various tissues of fish cultured in fish ponds fertilized with different or- ganic wastes have been studied. Twenty-five genera of bacteria were identified as associated with the fish tissues. The identified bacteria included one genus of spiral and curved bacteria, one genus of Gram-negative aerobic rod, sixteen gen- era of Gram-negative facultative anaerobic rods, one Gram-negative anaerobic bacterium, three Gram-positive cocci, two endospore-forming rods, and one Actinomycete. The bacterial contaminants were isolated from all tissues of the cultured fish. Higher bacterial contamination was associated with the gills, gut and skin than the blood and muscle. Although Pseudomonas sp. was most abundant species in the organic waste fertilized ponds and was present in considerable quanti- ties in the five fish tissues, Salmonella sp. was the most important contaminant of the gills, muscle and skin. The presence of high diversity of bacteria in the fish tissues presents health hazards to both consumers and fish farm workers. Handling and cleaning of the fish can result in contamination of hands of farm workers and through them to their family members and others. The digestive tract and intraperitoneal fluid of fish in this study showed high concentrations of pathogens, such as Salmonella in fish cultured in the organic waste fertilized ponds, but lower concentrations in fish cultured in non- fertilized pond. Public health must therefore be of prime concern when dealing with fish farming and its products in coun- tries, such as Ghana, with less restriction on release of waste into water bodies, and the use of untreated wastewater for aquaculture.

The Microbiological Quality of Sabil (Free) Drinking Water in Makkah Al-Mukarramah during Ramadan 2007

Eighty six samples of Sabil water were collected during 19- 29 of Ramadan 1428A.H. (1-10 October 2007) and examined using standard methods of analyses for drinking water, which include viable counts for total viable bacterial count (TVB), coliform bacteria count and presence of E.coli. In addition, water samples were examined for the presence of potential pathogens, and tested for their resistance to antibiotics by the disc diffusion method. Also, the occurrence of filamentous fungi together with bacteriological parameters was assessed in this study. Sabil water has a high bacterial contamination. Coliforms (39.71%), E. coli (13.24%) and other pathogenic bacteria were widely represented in the investigated Sabil water. In a first step to screen the waters for potentially pathogenic properties, 163 (47.8%) of the isolates showed α- or γ-haemolysis on human blood agar media. Among the haemolytic isolates, 45.1% were resistant to clindamycin and 52.3% to ampicillin. The most commonly isolated genera with these potentially pathogenic features were Bacillus spp., Streptococcus spp. Staphylococcus spp., Corynebacterium spp., E.coli, Proteus mirabilis, Proteus vulgaris, Pseudomonas aeuginosa, Aeromonas veronii, Acinetobacter spp. and Aeromonas hydrophila. While the most frequently isolated fungal species were Alternaria spp., Aspergillus spp., Cladosporium spp., Epidermophtton spp., Microsporum spp., Penicillium spp. The high bacterial contamination in Sabil water is related to human skin transmission and, probably to misuse of the water, such as using the same cups for drinking to perform the ritual washing, i.e. wodow (ablution).

The effect of municipal wastewater irrigation on the yield and quality of vegetables and crops

The effect of municipal wastewater irrigation on the yield and quality of vegetables and crops was studied by means of pot and lysimetric experiments. The pots were seeded with lettuce salad, radishes, and carrots in all experimental years; the lysimeters were planted with early potatoes in 2005 and 2007, and with sugar beet in 2006. Secondary-treated wastewater (in 2005) or only primary-treated wastewater (in 2006 and 2007) were used in the experiments. The control treatment involved the irrigation with water from a local well (in 2005) or public water supply (in 2006 and 2007). Contrarily to the secondary-treated wastewater, the primary-treated wastewater increased the yield of all vegetables and crops, the increase having been statistically significant in most cases. The irrigation with secondary-treated wastewater increased only the sodium content in radishes and carrots. However, the irrigation with primary-treated wastewater led to a statistically significant increase in the sodium content in the consumable parts of all vegetables, sugar beet bulbs, and potato tubers in both years, and in 2007, in the nitrate contents in lettuce salad and radishes as well. A high bacterial contamination of vegetables and crops irrigated with this wastewater was found out, but there was no evidence for the contamination with pathogens. Also, no risk was shown of contamination of the crops with intestinal nematodes.