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

2006 ◽  
Vol 6 (2) ◽  
pp. 47-53 ◽  
Author(s):  
D. Simazaki ◽  
M. Asami ◽  
T. Nishimura ◽  
S. Kunikane ◽  
T. Aizawa ◽  
...  

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.

1998 ◽  
Vol 37 (2) ◽  
pp. 9-18 ◽  
Author(s):  
Panagiotis Karanis ◽  
Dirk Schoenen ◽  
H. M. Seitz

This study has been conducted, to estimate the distribution of Giardia and Cryptosporidium in German water supplies and the removal efficiency of surface water treatment plants for Giardia and Cryptosporidium by conventional treatment. Water samples from six surface water treatment plants in different parts of Germany were simoultaneously examined for Giardia and Cryptosporidium. Investigations for both parasites were carried out in the period from July 1993 until December 1995. The results confirmed the occurrence of Giardia and Cryptosporidium in surface and raw water, in intermediate steps after treatment, in back wash water, in the first filtrate and in final water. Giardia or Cryptosporidium or both have been found in 76.2% of the investigated raw water sources. The average number of the detected Giardia cysts was 88.2/100 1 (max. 1314/100 1), and the average number of Cryptosporidium oocysts was 116/100 1 (max. 1081/100 1). In the intermediate steps (including flocculation and several steps of filtration), Giardia or Cryptosporidium or both have been found in 33.3% (50/150) of the samples. 14.9% of drinking water samples (7/47) were positive for Giardia (max. 16.8/100 1) and 29.8% (14/47) were positive for Cryptosporidium (max. 20.8/100 1). Overall, Giardia and Cryptosporidium, or both were detected in 38.3% of the drinking water samples. The parasites have been found in nearly all of the investigated backwash water samples. The filtrate of a rapid sand filter was analysed immediately after filter backwashing during the ripening period of the filter. Good elimination results were obtained by optimizing relevant water treatment process, but a low flocculant dose following sudden variation in the raw water quality, causes a breakthrough of Cryptosporidium into the treated water. Although water treatment technologies are effective to remove Giardia and Cryptosporidium, the results clearly show that Giardia and Cryptosporidium evade the filter barries in the absence of visible treatment deficiencies and low turbitidy level, and contaminate final water.


2021 ◽  
Vol 11 (2) ◽  
pp. 3498-3501

This study is based on an analysis of drinking water at Koya city, Kurdistan-Iraq. Since the source of tap water comes either from Dokan Lake or from groundwater resources. Therefore, ten samples from houses tab water of Koya city and ten samples from well-known brands of bottled water were collected. Concentrations of the metals in such water samples were analyzed by X-ray fluorescence and compared with WHO water quality standards for minerals. The experimental results show that most elements detected in this study were within the guidelines given by WHO for drinking water, while four elements of Ca, Al, Mg, and Cr were identified as risky elements in developing diseases since their level exceed the WHO standard levels. Positive relationships between risky elements and some serious diseases were discussed. Statistical work shows that elements; Ca, Al, and Cr have a high risk while Mg has a low risk.


2021 ◽  
Author(s):  
Rehana Shabnam

Finding low cost, rapid tests to monitor microcystins in water is paramount to protect environmental and public health worldwide. Bioassays like Protein Phosphatase Inhibition Assay (PPIA) and Enzyme-linked Immunosorbent Assay (ELISA) have many advantages over liquid chromatography–tandem mass spectrometry (LC-MS/MS). Analytical cost per sample was found to be $136 by ELISA and $365 by LC-MS/MS. An agreement of 76% was found between ELISA and LC-MS/MS results from 2010 to 2012 (n=854) on the basis of Method Detection Limits (MDLs). Among samples with LC-MS/MS results >1.5μg/L, ELISA missed 3 samples in 2010, 1 in 2011 and none in 2012. Correlation between PP2A and ELISA was strong (R2=0.8155, p=0.8054, n=27) in surface water samples but non-existent in drinking water (R2=0.0366, p=0.0665, n=38). PP2A was found useful for monitoring non-coloured surface water but not for drinking water. A 2-tier test system is proposed: tier-1 ELISA and tier-2 PP2A for surface water samples.


2018 ◽  
Vol 5 ◽  
pp. 83-88 ◽  
Author(s):  
Sujan Maharjan ◽  
Tista Prasai Joshi ◽  
Sujen Man Shrestha

Objectives: In order to evaluate the quality assurance of drinking water in Kathmandu valley, this study analyzed selected physiochemical and microbial parameters of treated water samples and compared with Nepal Drinking Water Quality Standards (NDWQS). Methods: Treated water samples were collected from all over the Kathmandu valley and analyzed in terms of physicochemical and microbiological parameters over the period of one year from July 2017 to July 2018. The physio-chemical parameters of water samples were performed according to standard methods for the examination of water and wastewater. The total coliforms were enumerated by standard membrane filtration technique. Results: We report that microbiological aspect of treated water was the major problem as 66% of the water samples crossed the guideline value for total coliform count. Above 92% of jar water samples, 77% of tanker water samples and 69% of filtered water samples had the total coliform count exceeding the NDWQS. Moreover, 20% of bottled water was contaminated by coliform bacteria. Iron and ammonia content were found to be higher than the guideline values in 16% and 21% of the total treated water samples respectively. Analyzing the types of treated water samples showed that 35% and 15% of tanker water samples had higher ammonia and iron content respectively, and the same parameters were higher in 23% and 19% in the filtered water samples respectively than the standard criteria recommended by NDWQS. Conclusion: The treated water samples exceed the standard values set by NDWQS and hence had poor quality. The presence of faecal pollution indicating coliform bacteria was the key problem for treated drinking water of Kathmandu valley. Therefore, monitoring and proper treatment of water should be conducted to prevent dissemination of waterborne diseases.


Author(s):  
Wonjin Sim ◽  
Sol Choi ◽  
Gyojin Choo ◽  
Mihee Yang ◽  
Ju-Hyun Park ◽  
...  

In this study, the concentrations of organophosphate flame retardants (OPFR) and perfluoroalkyl substances (PFAS) were investigated in raw water and treated water samples obtained from 18 drinking water treatment plants (DWTPs). The ∑13OPFR concentrations in the treated water samples (29.5–122 ng/L; median 47.5 ng/L) were lower than those in the raw water (37.7–231 ng/L; median 98.1 ng/L), which indicated the positive removal rates (0–80%) of ∑13OPFR in the DWTPs. The removal efficiencies of ∑27PFAS in the DWTPs ranged from −200% to 50%, with the ∑27PFAS concentrations in the raw water (4.15–154 ng/L; median 32.0 ng/L) being similar to or lower than those in the treated water (4.74–116 ng/L; median 42.2 ng/L). Among OPFR, tris(chloroisopropyl) phosphate (TCIPP) and tris(2-chloroethyl) phosphate (TCEP) were dominant in both raw water and treated water samples obtained from the DWTPs. The dominant PFAS (perfluorooctanoic acid (PFOA) and perfluorohexanoic acid (PFHxA)) in the raw water samples were slightly different from those in the treated water samples (PFOA, L-perfluorohexane sulfonate (L-PFHxS), and PFHxA). The 95-percentile daily intakes of ∑13OPFR and ∑27PFAS via drinking water consumption were estimated to be up to 4.9 ng/kg/d and 0.22 ng/kg/d, respectively. The hazard index values of OPFR and PFAS were lower than 1, suggesting the risks less than known hazardous levels.


2021 ◽  
Author(s):  
Fawzy Ismail Eissa ◽  
Mahmoud Al-Sisi ◽  
Khaled Ghanem

Abstract In Egypt, the shortage of freshwater resources and their pollution constitutes a growing concern. Therefore, the objectives of this study were to (i) monitor the occurrence and spatiotemporal variations of 100 pesticides in surface water samples collected monthly (from July 2018 to June 2019) from El-Rahawy, Sabal, and Tala sampling sites along the Rosetta branch of the River Nile in Egypt, (ii) identify potential non-carcinogenic health risks for the local people through the lifetime consumption of contaminated drinking water, and (iii) perform an ecological risk assessment of aquatic organisms upon exposure to pesticides detected in surface waters based on the risk quotients (RQs) method. Of the 100 pesticides analyzed, 22 belonging to 11 chemical families were detected, and 75.5% of surface water samples were contaminated with one or more pesticide residues. The most frequently detected pesticide was malathion (57%), followed by chlorpyrifos (54%), atrazine (23%), and carbendazim (20%). Spatial distribution showed that the El-Rahawy site had the highest pesticide load (38.47 µg/L), and Sabal had the lowest (16.29 µg/L). Temporal variations revealed that the highest total pesticide concentrations were detected in summer (27.98 µg/L) compared to spring (23.16 µg/L), winter (19.18 µg/L), and autumn (11.85 µg/L). For non-carcinogenic risks of pesticides detected in surface water, the target hazard quotient (THQ) values were less than one. This implies that there is no potential human risk from exposure to drinking water at the sites under study. However, 13 pesticides presented high-risk quotients (RQ > 1), posing potential ecological risks to aquatic organisms.


2021 ◽  
Author(s):  
Rehana Shabnam

Finding low cost, rapid tests to monitor microcystins in water is paramount to protect environmental and public health worldwide. Bioassays like Protein Phosphatase Inhibition Assay (PPIA) and Enzyme-linked Immunosorbent Assay (ELISA) have many advantages over liquid chromatography–tandem mass spectrometry (LC-MS/MS). Analytical cost per sample was found to be $136 by ELISA and $365 by LC-MS/MS. An agreement of 76% was found between ELISA and LC-MS/MS results from 2010 to 2012 (n=854) on the basis of Method Detection Limits (MDLs). Among samples with LC-MS/MS results >1.5μg/L, ELISA missed 3 samples in 2010, 1 in 2011 and none in 2012. Correlation between PP2A and ELISA was strong (R2=0.8155, p=0.8054, n=27) in surface water samples but non-existent in drinking water (R2=0.0366, p=0.0665, n=38). PP2A was found useful for monitoring non-coloured surface water but not for drinking water. A 2-tier test system is proposed: tier-1 ELISA and tier-2 PP2A for surface water samples.


Sign in / Sign up

Export Citation Format

Share Document