U.S. Geological Survey Protocol for Measuring Low Levels of Inorganic Constituents, Including Trace Elements, in Surface-Water Samples

ABSTRACT Cyclospora cayetanensis is a protozoan parasite that causes foodborne and waterborne diarrheal illness outbreaks worldwide. Most of these outbreaks are associated with the consumption of fresh produce. Sensitive and specific methods to detect C. cayetanensis in agricultural water are needed to identify the parasite in agricultural water used to irrigate crops that have been implicated in outbreaks. In this study, a method to detect C. cayetanensis in water by combining dead-end ultrafiltration (DEUF) with sensitive and specific molecular detection was developed and evaluated. Triplicates of 10-liter agricultural water samples were seeded with 200, 100, 25, 12, and 6 C. cayetanensis oocysts. Surface water samples were also collected in the Mid-Atlantic region. All water samples were processed by DEUF and backflushed from the ultrafilters. DNA was extracted from concentrated samples and analyzed by quantitative PCR (qPCR) targeting the C. cayetanensis 18S rRNA gene. All water samples seeded with 12, 25, 100, and 200 oocysts were positive, and all unseeded samples were negative. Samples seeded with 6 oocysts had a detection rate of 66.6% (8/12). The method was also able to detect C. cayetanensis isolates in surface water samples from different locations of the Chesapeake and Ohio Canal (C&O Canal) in Maryland. This approach could consistently detect C. cayetanensis DNA in 10-liter agricultural water samples contaminated with low levels of oocysts, equivalent to the levels that may be found in naturally incurred environmental water sources. Our data demonstrate the robustness of the method as a useful tool to detect C. cayetanensis from environmental sources. IMPORTANCE Cyclospora cayetanensis is a protozoan parasite that causes foodborne and waterborne outbreaks of diarrheal illness worldwide. These foodborne outbreaks associated with the consumption of fresh produce and agricultural water could play a role in the contamination process. In this study, a method to detect C. cayetanensis in agricultural water by combining a robust filtration system with sensitive and specific molecular detection was developed and validated by the FDA. The results showed that this approach could consistently detect low levels of C. cayetanensis contamination in 10 liters of agricultural water, corresponding to the levels that may be found in naturally occurring environmental water sources. The method was also able to detect C. cayetanensis in surface water samples from a specific location in the Mid-Atlantic region. Our data demonstrate the robustness of the method to detect C. cayetanensis in agricultural water samples, which could be very useful to identify environmental sources of contamination.

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Hydrochemical characteristics and environmental evaluation of surface and groundwater quality at Al-Tarmiyah Area, Baghdad, Iraq

Iraqi Journal of Science ◽

10.24996/ijs.2019.60.5.16 ◽

2019 ◽

Vol 60 (5) ◽

pp. 1069-1084

Author(s):

Mustafa Haqi Ismael ◽

Balsam Salim Al-Tawash ◽

Younus I. Al-Saady

Keyword(s):

Trace Elements ◽

Surface Water ◽

Water Samples ◽

Water Type ◽

Hydrochemical Characteristics ◽

Water Classification ◽

Groundwater Samples ◽

Acceptable Quality ◽

Surface Water Samples ◽

Surface And Groundwater

The present study aims to assess the water quality and the hydrochemical characteristics and seasonal variation of surface water on the aspect of trace elements in Al-Tarmiyah District, Baghdad, Iraq. Ten water samples were collected, four from surface water and six from groundwater on October 2017, and on April 2018. All samples were analyzed for physiochemical parameters such as water temperature, pH, EC, TDS,TH,TSS, major ions (Ca2+, Mg2+, Na+, K+, SO42-, Cl-, and HCO3-), and nutrients (NO3-, and PO43-). In addition, samples were analyzed for trace elements that include Fe, Al, Pb, Zn, Mn, Cr, Cu, Co, Ni, and Cd. Suitability of water for domestic uses was evaluated depending on the criteria or standards of acceptable quality for that use. Surface water samples of October 2017 were classified as Ca-Cl and Na-Cl water type while they were classified as Na-Cl water type in April 2018. Most groundwater of both months' samples was classified as Ca-Cl and Na-Cl water types. There is only one groundwater sample (GW2) was classified as Ca-SO4-2 water type. According to water classification based on the Piper diagram, most of surface and groundwater samples for both months falling in class (e), this means that the type of water is "Earth alkaline water with increased portions of alkalis with prevailing sulfate or chloride". Suitability of water for drinking purpose is evaluated depending on the criteria or standards of acceptable quality for that use ( WHO and Iraqi Standard). All surface and groundwater samples from the studied area are not suitable for drinking purposes and within "excellent typeâ€ for livestock and poultry use. Additionally, almost all surface water samples were within Good class based on the suggested limits of EC value (Ayers and Westcot, 1985) for irrigation while most of the groundwater samples are within unsuitable class. All surface water and groundwater samples lie within low hazard class of the irrigation water based on SAR values.

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Occurrence of 1,4-dioxane and MTBE in drinking water sources in Japan

Water Science & Technology Water Supply ◽

10.2166/ws.2006.049 ◽

2006 ◽

Vol 6 (2) ◽

pp. 47-53 ◽

Cited By ~ 5

Author(s):

D. Simazaki ◽

M. Asami ◽

T. Nishimura ◽

S. Kunikane ◽

T. Aizawa ◽

...

Keyword(s):

Drinking Water ◽

Surface Water ◽

Water Samples ◽

Quality Standards ◽

Raw Water ◽

Water Quality Standards ◽

Butyl Ether ◽

Water Treatment Plants ◽

Standard Value ◽

Surface Water Samples

Nationwide surveys of 1,4-dioxane and methyl-t-butyl ether (MTBE) levels in raw water used for the drinking water supply were conducted at 91 water treatment plants in Japan in 2001 and 2002, prior to the revision of the drinking water quality standards. 1,4-dioxane was widely and continuously detected in raw water samples and its occurrence was more frequent and its concentrations higher in groundwater than in surface water. However, its maximum concentration in raw water was much lower than its new standard value (50 μg/L), which was determined as a level of 10−5 excessive cancer risk to humans. Trace levels of MTBE were also detected in several surface water samples.

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Development of Surface Molecularly Imprinted Polymers as Dispersive Solid Phase Extraction Coupled with HPLC Method for the Removal and Detection of Griseofulvin in Surface Water

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17010134 ◽

2019 ◽

Vol 17 (1) ◽

pp. 134 ◽

Cited By ~ 1

Author(s):

Kamran Bashir ◽

Zhimin Luo ◽

Guoning Chen ◽

Hua Shu ◽

Xia Cui ◽

...

Keyword(s):

Surface Water ◽

Solid Phase Extraction ◽

Molecularly Imprinted Polymers ◽

Water Samples ◽

Solid Phase ◽

Phase Extraction ◽

Dispersive Solid Phase Extraction ◽

Molecularly Imprinted ◽

Imprinted Polymers ◽

Surface Water Samples

Griseofulvin (GSF) is clinically employed to treat fungal infections in humans and animals. GSF was detected in surface waters as a pharmaceutical pollutant. GSF detection as an anthropogenic pollutant is considered as a possible source of drug resistance and risk factor in ecosystem. To address this concern, a new extraction and enrichment method was developed. GSF-surface molecularly imprinted polymers (GSF-SMIPs) were prepared and applied as solid phase extraction (SPE) sorbent. A dispersive solid phase extraction (DSPE) method was designed and combined with HPLC for the analysis of GSF in surface water samples. The performance of GSF-SMIPs was assessed for its potential to remove GSF from water samples. The factors affecting the removal efficiency such as sample pH and ionic strength were investigated and optimized. The DSPE conditions such as the amount of GSF-SMIPs, the extraction time, the type and volume of desorption solvents were also optimized. The established method is linear over the range of 0.1–100 µg/mL. The limits of detection and quantification were 0.01 and 0.03 µg/mL respectively. Good recoveries (91.6–98.8%) were achieved after DSPE. The intra-day and inter-day relative standard deviations were 0.8 and 4.3% respectively. The SMIPs demonstrated good removal efficiency (91.6%) as compared to powder activated carbon (67.7%). Moreover, the SMIPs can be reused 10 times for water samples. This is an additional advantage over single-use activated carbon and other commercial sorbents. This study provides a specific and sensitive method for the selective extraction and detection of GSF in surface water samples.

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