Untreated Water Samples Research Articles

Occurrence of Salivirus in Sewage and River Water Samples in Karaj, Iran.

Salivirus is a newly discovered virus which seems to be related to acute gastroenteritis in children. Salivirus may infect susceptible children by fecal-oral route after exposure to contaminated water. The present study aims to evaluate the occurrence and quantity of Salivirus in treated and untreated sewage water and river water samples collected in the city of Karaj, Iran by reverse transcription-quantitative PCR assay. A total of 50 samples were collected from environmental waters containing 22 treated and untreated sewage water in volume of 1l and 28 river water samples in volume of 5l were included in this study. After viral RNA extraction, the Real-time PCR was performed to amplify the 5'UTR sequence of Salivirus genome and viral load was assessed. Out of the 50 samples tested, the Salivirus genomic RNA was identified in 5/12 (41.6%) of treated and 3/10 (30%) of untreated sewage samples and in 8/28 (28.5%) of river water samples. The maximum viral load was 4.8 × 106 copies/l in treated sewage water sample in September and the lower viral load was 4 × 105 copies/l related to treated sewage water taken in December. This is the first report of Salivirus occurrence in the environmental waters in Iran. The viral prevalence of Salivirus in each of the three sets of tested samples was within low to moderate in range.

Trends in neonicotinoid pesticide residues in food and water in the United States, 1999\u20132015

BackgroundNeonicotinoids are a class of systemic insecticides widely used on food crops globally. These pesticides may be found in “off-target” food items and persist in the environment. Despite the potential for extensive human exposure, there are limited studies regarding the prevalence of neonicotinoid residues in foods sold and consumed in the United States.MethodsResidue data for seven neonicotinoid pesticides collected between 1999 and 2015 by the US Department of Agriculture’s Pesticide Data Program (PDP) were collated and summarized by year across various food commodities, including fruit, vegetable, meat, dairy, grain, honey, and baby food, as well as water to qualitatively describe and examine trends in contamination frequency and residue concentrations.ResultsThe highest detection frequencies (DFs) for neonicotinoids by year on all commodities were generally below 20%. Average DFs over the entire study period, 1999–2015, for domestic and imported commodities were similar at 4.5%. For all the samples (both domestic and imported) imidacloprid was the neonicotinoid with the highest overall detection frequency at 12.0%. However, higher DFs were observed for specific food commodity-neonicotinoid combinations such as: cherries (45.9%), apples (29.5%), pears (24.1%) and strawberries (21.3%) for acetamiprid; and cauliflower (57.5%), celery (20.9%), cherries (26.3%), cilantro (30.6%), grapes (28.9%), collard greens (24.9%), kale (31.4%), lettuce (45.6%), potatoes (31.2%) and spinach (38.7%) for imidacloprid. Neonicotinoids were also detected in organic commodities, (DF < 6%). Individual commodities with at least 5% of samples testing positive for two or more neonicotinoids included apples, celery, and cherries. Generally, neonicotinoid residues on food commodities did not exceed US Environmental Protection Agency tolerance levels. Increases in detection trends for both finished and untreated water samples for imidacloprid were observed from 2004 to 2011.ConclusionsAnalysis of PDP data indicates that low levels of neonicotinoids are present in commonly-consumed fruits and vegetables sold in the US. Trends in detection frequencies suggest an increase in use of acetamiprid, clothianidin and thiamethoxam as replacements for imidacloprid. Given these findings, more extensive surveillance of the food and water supply is warranted, as well as biomonitoring studies and assessment of cumulative daily intake in high risk groups, including pregnant women and infants.

Direct speciation analysis of organophosphorus environmental pollutants in water by HPLC-ICPMS/MS

A new and optimized HPLC-ICPMS/MS method for the simultaneous determination of five of the most common phosphorous environmental pollutants in various water matrices has been developed, including aminomethylphosphonic acid (AMPA), glufosinate, glyphosate, fosamine, and ethephon. We show that the ICPMS/MS confers an average of 20-fold improvement in the detection limit (0.1–0.3 µg P L−1) relative to comparable methods based on single quadrupole ICPMS detection, without the incorporation of any sample purification or preconcentration step. The method was validated by determining the intra-day repeatability (< 6%), inter-day repeatability (< 10%) and recovery (86–112%) of 4 levels of spiking (5.0–250 µg L−1). The developed method involved utilizing the carbon enhancement effect which yielded up to 3-fold increase in sensitivity. A signal suppression effect exerted by the carbonate content of the analyzed water samples was identified, and should be generally taken into consideration when analyzing untreated hard water samples by HPLC-ICPMS. The developed method can be an important contribution in order to keep up with increasingly more stringent future regulations for the levels of the analyzed pollutants given their rising health concerns.

Development of a New 4-Amino-1,8-Naphthalimide Derivative as a Fluorescent Probe for Monitoring the Divalent Copper Ion

This article presents the design and synthesis of a new variant of the 4-amino-1,8-naphthalimide fluorescent probe for monitoring the divalent copper ion, Cu2+. The probe BRST, functionalized with two propionic carboxylic acid groups in its receptor moiety, demonstrated high selectivity and sensitivity for the detection of Cu2+ in competitive media of various metal ions in DMSO/HEPES buffer solution (1:1; pH 7.4), with a fluorescence quenching of 75.41%. Besides its good linearity with Cu2+, the probe yielded commendable values of the association constant and the detection limit, 5.54 × 105 M–1 and 4.33 × 10–9 M, respectively. The quenching of the fluorescence intensity of the sensor in the presence of Cu2+ ions is attributable to the strong paramagnetic nature of the Cu2+ ion. The fluorescence "turn off" behavior of this simple and effective probe was successfully applied for the determination of Cu2+ levels in untreated water samples, with excellent recovery rates of 98–105.8%.

Antimicrobial‐Resistant E. coli from Surface Waters in Southwest Ontario Dairy Farms

Untreated surface waters can be contaminated with a variety of bacteria, including , some of which can be pathogenic for both humans and animals. Therefore, such waters need to be treated before their use in dairy operations to mitigate risks to dairy cow health and milk safety. To understand the molecular ecology of , this study aimed to assess antimicrobial resistance (AMR) in recovered from untreated surface water sources of dairy farms. Untreated surface water samples ( = 240) from 15 dairy farms were collected and processed to isolate . A total of 234 isolates were obtained and further characterized for their serotypes and antimicrobial susceptibility. Of the 234 isolates, 71.4% were pan-susceptible, 23.5% were resistant to one or two antimicrobial classes, and 5.1% were resistant to three or more antimicrobial classes. Whole genome sequence analysis of 11 selected multidrug-resistant isolates revealed AMR genes including and that confer resistance to the critically important extended-spectrum cephalosporins, as well as a variety of plasmids (mainly of the replicon type) and class 1 integrons. Phylogenetic and comparative genome analysis revealed a genetic relationship between some of the sequenced and Shiga toxin-producing O157:H7 (STEC), which warrants further investigation. This study shows that untreated surface water sources contain antimicrobial-resistant which may serve as a reservoir of AMR that could be disseminated through horizontal gene transfer. This is another reason why effective water treatment before usage should be routinely done on dairy farm operations.

A sensitive and specific solid-phase extraction-gas chromatography-tandem mass spectrometry method for the determination of 11 haloacetic acids in aqueous samples.

A method for the analysis of 11 haloacetic acids in water samples has been developed. It involves enrichment of the target analytes from water samples by solid-phase extraction, derivatization to methyl esters, and gas chromatography coupled with tandem mass spectrometry determination. Gas chromatography conditions were optimized for a good separation of all haloacetic acids in a short runtime. Data were acquired in the multiple reaction monitoring mode. Six solid-phase extraction sorbents among the most widely used in environmental analysis were tested. Bakerbond SDB was retained because it has been shown to provide the best results for a large class of targeted haloacetic acids. The performances of the developed method have been assessed according to the French Standard NF T 90-210. The calibration curves for all the studied haloacetic acids had consistent slopes with r2 values > 0.99. Quantification limits between 0.01 and 0.50 µg l-1 were achieved. Satisfactory repeatability (relative standard deviation ≤ 14.3%) and intermediate precision (relative standard deviation ≤ 15.7%) were obtained. Applied to the analysis of 15 untreated water samples collected from three rivers, the method allowed the detection of five haloacetic acids including monochloroacetic acid (in 100% of the samples, <0.5-1.85 µg l-1), dichloroacetic acid (87%, <0.05-0.22 µg l-1), trichloroacetic acid (93%, <0.05-0.52 µg l-1), dibromoacetic acid (53%, <0.01-0.40 µg l-1), tribromoacetic acid (20%, <0.05-0.14 µg l-1), and bromodichloroacetic acid (6%, < 0.05 µg l-1).

Effects of water shortage stress on the morphology and expression of the gene encoding dihydrodipicolinate synthase (DHDPS) in Mesembryanthemum crystallinum

Lysine biosynthesis in plants has been studied extensively in order to improve the nutritional quality and provide the lysine for human life. In this process, dihydrodipicolinate synthase (DHDPS) is one of the important enzymes that determine the accumulation of lysine in plants. This paper presents the initial results of the effect of water stress on morphology and expression of gene encoding dihydrodipicolinate synthase (DHDPS) in Mesembryanthemum crystallinum leaves. M. crystallinum mature leaves have a lot of bladder cells which are surrounded and coated as the dewdrops sparkling on the outside of the leaves and twigs. When the external bladder cells of mature leaves were removed we can see a lot of stomata at both sides of the leaves under microscope with the objective lens 40 (Nikon, Eclipse 55I POL). When water stress treated after 5 days and 10 days, leaf morphology, cytoplasm and stomata of M. crystallinum mature plants were changed comparing with the control plants. The RNA was extracted from M. crystallinum leaves of both treated and untreated stress water samples. These RNA were used as a template to synthesize cDNA and analysis with specific primers by reverse transcription quantitative polymerase chain reaction (qRT-PCR). The results showed that water stress treatment had caused a change in the gene expression of DHDPH in treated plants significantly reduced the DHDPS gene expression in M. crystallinum leaves. In addition, a significant amount of DHDPS enzyme was measured in M. crystalium leaves, and the activity of that was changed by different water-stress treatment times.

Assessing Global Endocrine Disrupting Activity in Drinking Water with Bioassays: A Possible Tool for Population-Level Exposure Assessment

Background/Aim: Some natural and anthropogenic substances in drinking water sources are known or suspected endocrine disrupting chemicals (EDC), but few are regulated or routinely measured in U.S. public water supplies (PWS). Compared to measuring single analytes, bioassays that assess activity levels may better quantify population-level exposure to a variety of EDC. Methods: We conducted a pilot study of 10 PWS in Iowa, where agriculture-associated water contaminants (e.g., pesticides, nitrate) are suspected EDC. Source (untreated) water samples and finished (treated) drinking water samples were collected in spring and fall and concentrated 200x via a U.S. Geological Survey protocol. We assessed global EDC activity (aryl hydrocarbon [Ah], androgenic [AR], thyroid hormones [Ty], estrogenic [ER], and corticosteroid [CS]) with novel assays that express nuclear steroid receptor constructs in mammalian cell lines. We quantified statistically significant activity relative to negative controls and used bivariate and multivariate methods to compare activity overall, by season, and by utility/sample characteristics. Results: Among 62 samples (31 per season), 69% had significant Ah activity, 52% AR, 5% Ty, 2% ER and 2% CS. The percentage of samples with Ah activity was higher in the spring (84% versus 55%; c2p=0.01), and more common in utilities with ≥ median (≥ 3.19 mg/L) nitrate levels (p=0.04) or that were served by surface versus groundwater sources (p=0.02). AR activity was more common in spring versus fall samples (p&lt;0.001), and we found non-significant within-season contrasts in activity across strata of treatment and regulated contaminants. Multivariable analyses were imprecise, but suggested that surface waters and untreated samples had greater levels of Ah and AR activity after adjusting for other factors. Conclusions: Our pilot results indicate that specific types of EDC activities in PWS vary by season and utility characteristics. This holistic approach to measuring EDC may hold promise for characterizing population-level EDC exposures through drinking water.

Adsorptive Stripping Voltammetric Determination of Oxolinic Acid in Water Sample

One new methodology for analysis of the antimicrobial oxolinic acid (OXA) based on adsorptive stripping voltammetry (AdSV) in carbon paste electrode (CPE) was developed and applied in untreated pond water sample. Cyclic voltammetry (CV) indicated that an irreversible anodic process occurs in KOH solution as supporting electrolyte. Quantification of the antimicrobial was carried out by differential pulse adsorptive stripping voltammetry (DPAdSV) at potential of deposition (ED) +1.05 V for 45 s to examine OXA adsorption on the surface of CPE. The limits of detection (LOD) and quantification (LOQ) of the method for OXA analysis were determined. The values of LOD were 0.0570 and 0.512 mg L-1 in absence of matrix and in the water sample, respectively, and the corresponding values of LOQ were 0.192 and 1.707 mg L-1, respectively. The apparent recovery percentage for different concentrations of OXA in natural waters ranged between 98.4 and 109%.

Occurrence of Fungi in Drinking Water Sources and Their Treatment by Chlorination and UV-Irradiation

A TOTAL of 54 cfu/ml fungal species were isolated from 9 water samples collected from Nile water, Water Treatment Plant (WTP) and tap water in many governorates in Egypt. The fungal species Aspergillus alutaceus, A. flavus, A. fumigatus, A. niger, A. sulfurous, A. terreus, Penicillium chrysogenum, P. globrum and Trichoderma viride were isolated from water samples. Nile water (S1) was polluted with the highest fungal count and diversity followed by treated tap water in Al Sharqia (S5) Governorate. The physicochemical analysis revealed higher COD and conductivity in Al Sharqia tap water sample than that in untreated Nile water sample which may be due to the old rusted distribution systems or heavy metals contamination. Laboratory scale treatment of tap water in Al Sharqia sample (S5) indicated that single treatment with chlorination was not efficient to eliminate fungal contamination except by using high chlorine concentration with long exposure time. Similarly single UV treatment to drinking water was not effective enough. Combination between UV irradiation followed by chlorination exerted synergistic effect and disinfected water from fungal contamination in very short exposure time and very low chlorine concentration.

Coxsackievirus B4 as a Causative Agent of Diabetes Mellitus Type 1: Is There a Role of Inefficiently Treated Drinking Water and Sewage in Virus Spreading?

This study proposed to detect the enterovirus (EV) infection in children with type 1 diabetes mellitus (T1D) and to assess the role of insufficiently treated water and sewage as sources of viral spreading. Three hundred and eighty-two serum specimens of children with T1D, one hundred serum specimens of children who did not suffer from T1D as control, and forty-eight water and sewage samples were screened for EV RNA using nested RT-PCR. The number of genome copies and infectious units of EVs in raw and treated sewage and water samples were investigated using real-time (RT)-PCR and plaque assay, respectively. T1D markers [Fasting blood glucose (FBG), HbA1c, and C-peptide], in addition to anti-Coxsackie A & B viruses (CVs A & B) IgG, were measured in control, T1D-negative EV (T1D-EV-), and T1D-positive EV (T1D-EV+) children specimens. The prevalence of EV genome was significantly higher in diabetic children (26.2%, 100 out of 382) than the control children (0%, 0 out of 100). FBG and HbA1c in T1D-EV- and T1D-EV+ children specimens were significantly higher than those in the control group, while c-peptide in T1D-EV- and T1D-EV+ children specimens was significantly lower than that in the control (n=100; p<0.001). Positivity of anti-CVs A & B IgG was 70.7, 6.7, and 22.9% in T1D-EV+, T1D-EV-, and control children specimens, respectively. The prevalence of EV genome in drinking water and treated sewage samples was 25 and 33.3%, respectively. The prevalence of EV infectious units in drinking water and treated sewage samples was 8.5 and 25%, respectively. Quantification assays were performed to assess the capabilities of both wastewater treatment plants (WWTPs) and water treatment plants (WTPs) to remove EV. The reduction of EV genome in Zenin WWTP ranged from 2 to 4 log10, while the reduction of EV infectious units ranged from 1 to 4 log10. The reduction of EV genome in El-Giza WTP ranged from 1 to 3 log10, while the reduction of EV infectious units ranged from 1 to 2 log10. This capability of reduction did not prevent the appearance of infectious EV in treated sewage and drinking water. Plaque purification was performed for isolation of separate EV isolates from treated and untreated water and sewage samples. Characterization of the EV amplicons by RT-PCR followed by sequencing of these isolates revealed high homology (97%) with human coxsackievirus B4 (CV B4) in 60% of the isolates, while the rest of the isolates belonged to poliovirus type 1 and type 2 vaccine strains. On the other hand, characterization of the EV amplicons by RT-PCR followed by sequencing for T1D-EV+ children specimens indicated that all samples contained CV B4 with the same sequence characterized in the environmental samples. CV B4-contaminated drinking water or treated sewage may play a role as a causative agent of T1D in children.

Retention of metal and sulphate ions from acidic mining water by anionic nanofibrillated cellulose

We carried out an adsorption experiment to investigate the ability of anionic nanofibrillated cellulose (NFC) to retain metal and SO42− ions from authentic highly acidic (pH3.2) mining water. Anionic NFC gels of different consistencies (1.1-%, 1.4-% and 1.8-% w/w) were allowed to react for 10min with mining water, after which NFC-induced changes in the metal and SO42− concentrations of the mining water were determined. The sorption capacities of the NFC gels were calculated as the difference between the element concentrations in the untreated and NFC-treated mining water samples. All the NFCs efficiently co-adsorbed both metals and SO42−. The retention of metals was concluded to take place through formation of metal-ligand complexes. The reaction between the NFC ligand and the polyvalent cations renders the cellulose nanofibrils positively charged and, thus, able to retain SO42− electrostatically. Adsorption capacity of the NFC gels substantially increased upon decreasing DM content as a result of the dilution-induced weakening of the mutual interactions between individual cellulose nanofibrils. This outcome reveals that the dilution of the NFC gel not only increases its purification capacity but also reduces the demand for cellulosic raw material. These results suggest that anionic NFC made of renewable materials serves as an environmentally sound and multifunctional purification agent for acidic multimetal mining waters or AMDs of high ionic strength. Unlike industrial minerals traditionally used to precipitate valuable metals from acidic mining effluents before their permanent disposal from the material cycle, NFC neither requires mining of unrenewable raw materials nor produces inorganic sludges.

Pathogenic waterborne free-living amoebae: An update from selected Southeast Asian countries.

Data on the distribution of free-living amoebae is still lacking especially in Southeast Asian region. The aquatic environment revealed a high occurrence of free-living amoebae (FLA) due to its suitable condition and availability of food source, which subsequently causes infection to humans. A total of 94 water samples consisted of both treated and untreated from Laos (31), Myanmar (42), and Singapore (21) were investigated for the presence of pathogenic FLA. Each water sample was filtered and cultured onto non-nutrient agar seeded with live suspension of Escherichia coli and incubated at room temperature. Morphological identification was conducted for both trophozoites and cysts via microscopic stains (Giemsa and immunofluorescence). The presence of Naegleria-like structures was the most frequently encountered in both treated and untreated water samples, followed by Acanthamoeba-like and Vermamoeba-like features. To identify the pathogenic isolates, species-specific primer sets were applied for molecular identification of Acanthamoeba, Naegleria, and Vermamoeba. The pathogenic species of Acanthamoeba lenticulata and A. triangularis were detected from untreated water samples, while Vermamoeba vermiformis was found in both treated and untreated water samples. Our results suggested that poor water quality as well as inadequate maintenance and treatment might be the cause of this alarming problem since chlorine disinfection is ineffective in eradicating these amoebas in treated water samples. Regular monitoring and examination of water qualities are necessary in order to control the growth, hence, further preventing the widespread of FLA infections among the public.

Examination of an indicative tool for rapidly estimating viable organism abundance in ballast water

Regulatory discharge standards stipulating a maximum allowable number of viable organisms in ballast water have led to a need for rapid, easy and accurate compliance assessment tools and protocols. Some potential tools presume that organisms present in ballast water samples display the same characteristics of life as the native community (e.g. rates of fluorescence). This presumption may not prove true, particularly when ships' ballast tanks present a harsh environment and long transit times, negatively impacting organism health. Here, we test the accuracy of a handheld pulse amplitude modulated (PAM) fluorometer, the Hach BW680, for detecting photosynthetic protists at concentrations above or below the discharge standard (<10 cells·ml−1) in comparison to microscopic counts using fluorescein diacetate as a viability probe. Testing was conducted on serial dilutions of freshwater harbour samples in the lab and in situ untreated ballast water samples originating from marine, freshwater and brackish sources utilizing three preprocessing techniques to target organisms in the size range of ≥10 and <50μm. The BW680 numeric estimates were in agreement with microscopic counts when analyzing freshly collected harbour water at all but the lowest concentrations (<38 cells·ml−1). Chi-square tests determined that error is not independent of preprocessing methods: using the filtrate method or unfiltered water, in addition to refining the conversion factor of raw fluorescence to cell size, can decrease the grey area where exceedance of the discharge standard cannot be measured with certainty (at least for the studied populations). When examining in situ ballast water, the BW680 detected significantly fewer viable organisms than microscopy, possibly due to factors such as organism size or ballast water age. Assuming both the BW680 and microscopy with FDA stain were measuring fluorescence and enzymatic activity/membrane integrity correctly, the observed discrepancy between methods may simply reflect that the two methods are measuring different characteristics of life. This is the first study to conduct proof-of-concept testing for a rapid compliance detection tool using freshly collected harbour water concomitantly with in situ ballast water; our results demonstrate that it is important to challenge potential compliance tools with water samples spanning a range of biotic and abiotic conditions.

Application of modified hollow fiber liquid phase microextraction in conjunction with chromatography-electron capture detection for quantification of acrylamide in waste water samples at ultra-trace levels

Herein, a simple and sensitive method was successfully developed for the extraction and quantification of acrylamide in water samples. Initially, acrylamide was derivatized through a bromination process. Subsequently, a modified hollow-fiber liquid-phase microextraction was applied for the extraction of the brominated acrylamide from a 10-ml portion of an aqueous sample. Briefly, in this method, the derivatized acrylamide (2,3-dibromopropionamide) was extracted from the aqueous sample into a thin layer of an organic solvent sustained in pores of a porous hollow fiber. Then, it was back-extracted using a small volume of organic acceptor solution (acetonitril, 25μl) located inside the lumen of the hollow fiber followed by gas chromatography–electron capture detection (GC–ECD). The optimal conditions were examined for the extraction of the analyte such as: the organic solvent: dihexyl ether+10% tri-n-octyl phosphine oxide; stirring rate: 750rpm; no salt addition and 30min extraction time. These optimal extraction conditions allowed excellent enrichment factor values for the method. Enrichment factor, detection limit (S/N=3) and dynamic linear range of 60, 2ngL−1 and 50–1000ngL−1 to be determined for the analyte. The relative standard deviations (RSD%) representing precision of the method were in the range of 2.2–5.8 based on the average of three measurements. Accuracy of the method was tested by the relative recovery experiments on spiked samples, with results ranging from 93 to 108%. Finally, the method proved to be simple, rapid, and cost-effective for routine screen of acrylamide-contaminated highly-complicated untreated waste water samples.

Estimation of coastal residence time of submarine groundwater discharge using radium progenies

A methodology based on γ-spectrometry measurements of untreated coastal water samples is proposed for the direct estimation of coastal residence time of submarine discharged groundwater. The method was applied to a submarine spring at Stoupa Bay covering all seasons. The estimated residence time exhibited an annual mean of 4.6±1.7 d. An additional measurement using the in situ underwater γ-spectrometry technique was performed, in the same site. The in situ method yielded a value of 2.8±0.2 d that was found consistent with the corresponding value derived using the developed lab-based method (3.4±2.0 d) for the same period.

Point-of-use Unit Based on Gravity Ultrafiltration Removes Waterborne Gastrointestinal Pathogens from Untreated Water Sources in Rural Communities

In developing countries, rural communities often face the lack of potable water infrastructure and must rely on untreated sources for drinking, which are often contaminated with waterborne pathogens. The use of home water treatment devices is seen as one means of reducing the risk of exposure to waterborne pathogens. The aim of this study was to evaluate the microbiological and physicochemical performance of a simple in-home point-of-use device based on gravity ultrafiltration through an ultrafilter membrane. Twenty-five randomly selected households from 2 rural communities in Culiacán, Mexico, were enrolled. Water samples were collected before and after treatment and during storage for a period of 8 weeks. Heterotrophic bacteria, total coliforms, fecal coliforms, Escherichia coli, and Giardia spp were quantified, as well as various physicochemical parameters. All of the untreated water samples contained high levels of indicator bacteria, but none were detected in the treated water fulfilling the requirements set by the Mexican Norm (NOM-127-SSA1-1994) and the World Health Organization guidelines for drinking water. However, indicator bacteria (fecal coliforms and E coli) were detected in every sample from water stored 24 hours after treatment. This study demonstrated that point-of-use filters using gravity-fed ultrafilters are a low-cost, effective water treatment technology for water of poor microbial quality. However, further identification of the sources and mechanisms by which water is contaminated when stored after treatment will help with designing and implementing better strategies for keeping water safe for domestic use.

Bioswales reduce contaminants associated with toxicity in urban storm water.

Contamination and toxicity associated with urban storm water runoff are a growing concern because of the potential impacts on receiving systems. California water regulators are mandating implementation of green infrastructure as part of new urban development projects to treat storm water and increase infiltration. Parking lot bioswales are low impact development practices that promote filtering of runoff through plants and soil. Studies have demonstrated that bioswales reduce concentrations of suspended sediments, metals, and hydrocarbons. There have been no published studies evaluating how well these structures treat current-use pesticides, and studies have largely ignored whether bioswales reduce toxicity in surface water. Three storms were monitored at 3 commercial and residential sites, and reductions of contaminants and associated toxicity were quantified. Toxicity testing showed that the majority of untreated storm water samples were toxic to amphipods (Hyalella azteca) and midges (Chironomus dilutus), and toxicity was reduced by the bioswales. No samples were toxic to daphnids (Ceriodaphnia dubia) or fish (Pimephales promelas). Contaminants were significantly reduced by the bioswales, including suspended solids (81% reduction), metals (81% reduction), hydrocarbons (82% reduction), and pyrethroid pesticides (74% reduction). The single exception was the phenypyrazole pesticide fipronil, which showed inconsistent treatment. The results demonstrate these systems effectively treat contaminated storm water associated with surface water toxicity but suggest that modifications of their construction may be required to treat some contaminant classes. Environ Toxicol Chem 2016;35:3124-3134. © 2016 SETAC.

Presence of Cryptosporidium parvum and Giardia lamblia in water samples from Southeast Asia: towards an integrated water detection system.

BackgroundAccess to clean and safe drinking water that is free from pathogenic protozoan parasites, especially Cryptosporidium parvum and Giardia lamblia that cause gastrointestinal illness in humans, is still an issue in Southeast Asia (SEA). This study is the first attempt to detect the aforementioned protozoan parasites in water samples from countries in SEA, using real-time polymerase chain reaction (qPCR) assays.MethodsA total of 221 water samples of 10 l each were collected between April and October 2013 from Malaysia (53), Thailand (120), the Philippines (33), and Vietnam (15). A physicochemical analysis was conducted. The water samples were processed in accordance with the US Environmental Protection Agency’s methods 1622/1623.1, microscopically observed and subsequently screened using qPCR assays.ResultsCryptosporidium oocysts were detected in treated water samples from the Philippines (1/10), with a concentration of 0.06 ± 0.19 oocyst/L, and untreated water samples from Thailand (25/93), Malaysia (17/44), and the Philippines (11/23), with concentrations ranging from 0.13 ± 0.18 to 0.57 ± 1.41 oocyst/L. Giardia cysts were found in treated water samples from the Philippines (1/10), with a concentration of 0.02 ± 0.06 cyst/L, and in untreated water samples from Thailand (20/93), Vietnam (5/10), Malaysia (22/44), and the Philippines (16/23), with concentrations ranging from 0.12 ± 0.3 to 8.90 ± 19.65 cyst/L. The pathogens C. parvum and G. lamblia were detected using using qPCR assays by targeting the 138-bp fragment and the small subunit gene, respectively. C. parvum was detected in untreated water samples from the Philippines (1/23) and Malaysia (2/44), whilst, G. lamblia detected was detected in treated water samples from the Philippines (1/10) and in untreated water samples from Thailand (21/93), Malaysia (12/44), and the Philippines (17/23). Nitrate concentration was found to have a high positive correlation with (oo)cyst (0.993).ConclusionThe presence of (oo)cysts in the water samples means that there is potential risk for zoonotic disease transmission in the studied countries. Detection using qPCR is feasible for quantifying both pathogenic C. parvum and G. lamblia in large water samples.

PERFORMANCE OF HOUSEHOLD WATER TREATMENT METHODS FOR MICROBIAL REMOVAL UNDER HOUSEHOLD CONDITIONS IN KABALE DISTRICT, UGANDA

Despite the Ugandan government efforts to improve access to safe water sources, the rate at which diseases spread as a result of unsafe drinking water is absolutely high. The purpose the study was to assess the performance of household water treatment methods (HWT) and evaluate their ability to improve the microbial quality of drinking water under household conditions in Kabale District. We randomly selected 205 households, where we collected treated and untreated water samples. We analyzed 46 paired samples (untreated and treated) of drinking water from 46 households that reported treated water available. Samples were analyzed for total coliforms and Escherichia coli, the major indicators of biological contamination of drinking water, to measure effectiveness of treatment under household conditions. All reported HWT did not significantly improve the microbial quality of drinking water. Mean log10 total coliforms removal were 0.7 log10 (40.1%) for boiling method, 0.2 log10 (23.7%) for biosand filtration method, -0.01log10(-18.1%) for let it stand and settle method and 0.1 log10 (16%) for application of aqua safe tablets. In addition, mean log10 Escherichia coli removal were 0.7 log10 (-22.6) for boiling method, 0.3log10 (37.5%) for biosand filtration method, -0.4 log10 (-200%) for let it stand and settle method and 0.6 log10 (50%) for application of aqua safe. The microbiological quality of stored treated drinking water was significantly low. The government should sensitize the local people on safe storage of drinking water.