Tamanna Islam, M. Acharjee, M. Acharjee, N. Tabassum, Mahima Ranjan Acharjee
Present study assessed the pathogenic prevalence in municipal water from 10 supply point and deep tube-well water from 10 deep tube-well point delivered across the Kashipur zone of Narayanganj city, Bangladesh along with their drug resistant pattern through conventional, biochemical and disk diffusion methods. The physico-chemical properties of the deep tube-well water were in satisfactory level, only the samples from location 1, 3, 5 and 9 were exceed the marginal limit for dissolved oxygen however most of the samples of supplied water cross the marginal limit of all parameter (dissolved oxygen ,temperature, pH, electrical conductivity, total dissolve solid and turbidity). Pathogenic bacteria including Escherichia coli and Staphylococcus spp. were found in both supplied water and sewerage authority water (102–106 cfu/ml) and deep tube-well water (102–104 cfu/ml). Additionally, fecal coliforms, Klebsiella spp., Salmonella spp., Shigella spp., Vibrio spp. and Pseudomonas spp. was monitored only among the supplied water. Both of the samples were found to be contaminated with heterotrophic bacteria up to 108 cfu/ml. Most of the bacteria were found to be resistant against more than one drug. Hence, the municipal water of the study area was microbiologically unsafe. The propagation of drug resistant strains was assumed to escalate the public health threat. A survey on public opinions were also conducted to know their daily life style and their concern on water treatment and diseases outbreaks caused by contaminated water.
{"title":"Bacterial Propagation in Municipal Water and Deep Tube-well Water in Kashipur Locality of Narayanganj City, Bangladesh","authors":"Tamanna Islam, M. Acharjee, M. Acharjee, N. Tabassum, Mahima Ranjan Acharjee","doi":"10.2965/jwet.20-049","DOIUrl":"https://doi.org/10.2965/jwet.20-049","url":null,"abstract":"Present study assessed the pathogenic prevalence in municipal water from 10 supply point and deep tube-well water from 10 deep tube-well point delivered across the Kashipur zone of Narayanganj city, Bangladesh along with their drug resistant pattern through conventional, biochemical and disk diffusion methods. The physico-chemical properties of the deep tube-well water were in satisfactory level, only the samples from location 1, 3, 5 and 9 were exceed the marginal limit for dissolved oxygen however most of the samples of supplied water cross the marginal limit of all parameter (dissolved oxygen ,temperature, pH, electrical conductivity, total dissolve solid and turbidity). Pathogenic bacteria including Escherichia coli and Staphylococcus spp. were found in both supplied water and sewerage authority water (102–106 cfu/ml) and deep tube-well water (102–104 cfu/ml). Additionally, fecal coliforms, Klebsiella spp., Salmonella spp., Shigella spp., Vibrio spp. and Pseudomonas spp. was monitored only among the supplied water. Both of the samples were found to be contaminated with heterotrophic bacteria up to 108 cfu/ml. Most of the bacteria were found to be resistant against more than one drug. Hence, the municipal water of the study area was microbiologically unsafe. The propagation of drug resistant strains was assumed to escalate the public health threat. A survey on public opinions were also conducted to know their daily life style and their concern on water treatment and diseases outbreaks caused by contaminated water.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69264579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sachiko Shiode, Kathleen McDonough, S. Belanger, G. Carr
The environmental risk of the anionic surfactant, linear alkylbenzene sulfonate (LAS), in Japanese surface waters is presented using a probabilistic exposure and effects assessment. A chronic toxicity Species Sensitivity Distribution (SSD) (20 species) is used to define the 5th percentile hazardous concentration and compared to experimental stream mesocosm findings following toxicity normalization to various LAS carbon chain lengths (CL) ranging from C10 to C14. CL-dependent ecotoxicity data are combined with environmental monitoring in Japan where CL distributions of LAS are also quantified. Over 9,000 surface water measurements with CL specific LAS concentrations were compiled. Because LAS displays a common polar narcotic mode of action across all CL, a Toxic Unit (TU) concentration-addition approach can be followed whereby TU exceeding 1 correspond to environmental risk of cumulative Predicted Exposure Concentrations (PEC)/Predicted No Effects Concentration (PNEC) also exceeding 1. SSD, mesocosm, and monitoring data confirm that an extremely small number of water samples exceed a TU of 1 (5 of 4748 for SSD PNEC; 0 sites for mesocosm PNEC). Total LAS measurements from > 25,000 sites were compared to CL normalized PNECs demonstrating > 99.99% probability that the PEC would be less than the PNEC indicating negligible risk from LAS in Japan surface waters.
{"title":"Probabilistic Environmental Risk Assessment for Linear Alkyl Benzene Sulfonate (LAS) in Japan Reduces Assessment Uncertainty","authors":"Sachiko Shiode, Kathleen McDonough, S. Belanger, G. Carr","doi":"10.2965/jwet.19-016","DOIUrl":"https://doi.org/10.2965/jwet.19-016","url":null,"abstract":"The environmental risk of the anionic surfactant, linear alkylbenzene sulfonate (LAS), in Japanese surface waters is presented using a probabilistic exposure and effects assessment. A chronic toxicity Species Sensitivity Distribution (SSD) (20 species) is used to define the 5th percentile hazardous concentration and compared to experimental stream mesocosm findings following toxicity normalization to various LAS carbon chain lengths (CL) ranging from C10 to C14. CL-dependent ecotoxicity data are combined with environmental monitoring in Japan where CL distributions of LAS are also quantified. Over 9,000 surface water measurements with CL specific LAS concentrations were compiled. Because LAS displays a common polar narcotic mode of action across all CL, a Toxic Unit (TU) concentration-addition approach can be followed whereby TU exceeding 1 correspond to environmental risk of cumulative Predicted Exposure Concentrations (PEC)/Predicted No Effects Concentration (PNEC) also exceeding 1. SSD, mesocosm, and monitoring data confirm that an extremely small number of water samples exceed a TU of 1 (5 of 4748 for SSD PNEC; 0 sites for mesocosm PNEC). Total LAS measurements from > 25,000 sites were compared to CL normalized PNECs demonstrating > 99.99% probability that the PEC would be less than the PNEC indicating negligible risk from LAS in Japan surface waters.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2965/jwet.19-016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69262396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The people in Thailand generally soak sticky rice in water for 12–24 h before steaming and rinse jasmine rice before cooking. This study aimed at estimating fluoride intake from rice by the measuring rice consumption and examining factors affecting fluoride adsorption on jasmine rice and sticky rice in Buak Khang Subdistict, Chiang Mai Province, Thailand. It was found that 65.7% of 35 households still use tap water containing fluoride at 5.94 ± 0.29 mg/L of fluoride for rice soaking and rinsing. The amount of jasmine rice and sticky rice consumption was 0.096 ± 0.05 kg/meal and 0.114 ± 0.06 kg/ meal, respectively. The fluoride taken up into rice exhibited a positive correlation with the initial fluoride in water, the duration and water volume for rice soaking. The fluoride intake from jasmine rice and sticky rice based on the field survey was 0.004 ± 0.007 mg/kg-bw/day and 0.025 ± 0.024 mg/ kg-bw/day, respectively. The results of this study indicated that eating rice can significantly contribute to the total amount of fluoride intake; thus, it is recommended to use fluoride-free water or reducing time duration for rice soaking in areas using fluoride-containing groundwaters.
{"title":"Assessment of Fluoride Intake from Rice Consumption by Using Tap Water Containing Fluoride for Rice Soaking Water","authors":"Benyapa Sawangjang, S. Takizawa","doi":"10.2965/jwet.19-084","DOIUrl":"https://doi.org/10.2965/jwet.19-084","url":null,"abstract":"The people in Thailand generally soak sticky rice in water for 12–24 h before steaming and rinse jasmine rice before cooking. This study aimed at estimating fluoride intake from rice by the measuring rice consumption and examining factors affecting fluoride adsorption on jasmine rice and sticky rice in Buak Khang Subdistict, Chiang Mai Province, Thailand. It was found that 65.7% of 35 households still use tap water containing fluoride at 5.94 ± 0.29 mg/L of fluoride for rice soaking and rinsing. The amount of jasmine rice and sticky rice consumption was 0.096 ± 0.05 kg/meal and 0.114 ± 0.06 kg/ meal, respectively. The fluoride taken up into rice exhibited a positive correlation with the initial fluoride in water, the duration and water volume for rice soaking. The fluoride intake from jasmine rice and sticky rice based on the field survey was 0.004 ± 0.007 mg/kg-bw/day and 0.025 ± 0.024 mg/ kg-bw/day, respectively. The results of this study indicated that eating rice can significantly contribute to the total amount of fluoride intake; thus, it is recommended to use fluoride-free water or reducing time duration for rice soaking in areas using fluoride-containing groundwaters.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"18 1","pages":"117-131"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2965/jwet.19-084","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69263062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sayak Das, Goshaidas Roy, M. Sherpa, I. Najar, Nagendra Thakur
The major recreational hot springs of Sikkim which are famous tourist destinations were selected for the current study. Physicochemical and microbial quality of all the seven hot spring water samples were examined to assess the seasonal variation for three months. Polok hot spring was the hottest among all, whose temperature reached up to 75°C. In all the other hot springs, temperature ranged from 40 ° C to 50 ° C. Piper diagram, durov plot and schoeller plot categorized these hot springs as calcium chloride type. Elemental analysis showed similar pattern of composition in all the hot springs. Various other parameters such as total hardness of water, total alkalinity, phenolic compounds, biochemical oxygen demand, chemical oxygen demand were analyzed and they were found to be within the permissible limits of American Public Health Association and Bureau of Indian Standards. There was no growth in any differential and selection media used for the detection of coli-aerogenes, enteric bacterial pathogens belonging to Enterobacteriaceae , Salmonella - Shigella sp., Vibrio sp. and Pseudomonas sp. Hence, the hot springs of Sikkim are safe for recreational purposes.
{"title":"Chemical Ecology and Microbial Quality Assessment of Water of Recreational Hot Springs of Sikkim Himalayas","authors":"Sayak Das, Goshaidas Roy, M. Sherpa, I. Najar, Nagendra Thakur","doi":"10.2965/jwet.20-056","DOIUrl":"https://doi.org/10.2965/jwet.20-056","url":null,"abstract":"The major recreational hot springs of Sikkim which are famous tourist destinations were selected for the current study. Physicochemical and microbial quality of all the seven hot spring water samples were examined to assess the seasonal variation for three months. Polok hot spring was the hottest among all, whose temperature reached up to 75°C. In all the other hot springs, temperature ranged from 40 ° C to 50 ° C. Piper diagram, durov plot and schoeller plot categorized these hot springs as calcium chloride type. Elemental analysis showed similar pattern of composition in all the hot springs. Various other parameters such as total hardness of water, total alkalinity, phenolic compounds, biochemical oxygen demand, chemical oxygen demand were analyzed and they were found to be within the permissible limits of American Public Health Association and Bureau of Indian Standards. There was no growth in any differential and selection media used for the detection of coli-aerogenes, enteric bacterial pathogens belonging to Enterobacteriaceae , Salmonella - Shigella sp., Vibrio sp. and Pseudomonas sp. Hence, the hot springs of Sikkim are safe for recreational purposes.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69265089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In Japan, data on the reproduction sensitivity of Daphnia magna , which is a widely used organism in laboratory toxicity tests, to nickel are key to determination of water quality target values for nickel, which are used to set values for the environmental quality standards for conservation of the living environment. However, the use of data on the sensitivity of more than one species, including native species, will provide more relevant values. In this study, sensitivity of reproduction to nickel was investigated for five Daphnia species, D. magna , D. similis , D. pulex , D. galeata and D. ambigua , four of which are native to Japan. The no observed effect concentration and the 10% effect concen tration (EC 10 ) values of dissolved nickel for reproduction were below the lowest test concentration and 7.9 µg/L for D. magna , 4.6 and 11.2 µg/L for D. similis , 26 and 25.8 µg/L for D. pulex , 23 and 41.0 µg/L for D. galeata , and 62 and 63.8 µg/L for D. ambigua , respectively. Our results indicate that use of ecotoxicity data for native, ecologically relevant Daphnia species can strongly influence the determination of the water quality target values for nickel.
{"title":"Reproduction Sensitivity of Five Daphnia Species to Nickel","authors":"H. Mano, N. Shinohara, W. Naito","doi":"10.2965/jwet.20-083","DOIUrl":"https://doi.org/10.2965/jwet.20-083","url":null,"abstract":"In Japan, data on the reproduction sensitivity of Daphnia magna , which is a widely used organism in laboratory toxicity tests, to nickel are key to determination of water quality target values for nickel, which are used to set values for the environmental quality standards for conservation of the living environment. However, the use of data on the sensitivity of more than one species, including native species, will provide more relevant values. In this study, sensitivity of reproduction to nickel was investigated for five Daphnia species, D. magna , D. similis , D. pulex , D. galeata and D. ambigua , four of which are native to Japan. The no observed effect concentration and the 10% effect concen tration (EC 10 ) values of dissolved nickel for reproduction were below the lowest test concentration and 7.9 µg/L for D. magna , 4.6 and 11.2 µg/L for D. similis , 26 and 25.8 µg/L for D. pulex , 23 and 41.0 µg/L for D. galeata , and 62 and 63.8 µg/L for D. ambigua , respectively. Our results indicate that use of ecotoxicity data for native, ecologically relevant Daphnia species can strongly influence the determination of the water quality target values for nickel.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69265934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Algal water blooms in lakes or reservoirs are often caused by an enrichment of phosphorus. Depending on a bottom environment, dissolved phosphorus (phosphate) can be released into a water column from bottom sediments and accelerate algal and macrophyte nutrient dynamics. This study focuses on phosphorus pollutant loads in stormwater wash-off from roadways. Control of phosphorus discharge from non-point sources in urban areas is important for preventing water pollution. Sources of phosphorus in pollutant loads were explored by comparing first flush runoff with road dust/water mixture and vehicle wash-off water, where characteristics of the particulate and dissolved portions, and the relationship between road dust and wash-off from vehicles were also discussed. It was clear that the concentration of dissolved phosphorus in the vehicle wash-off water was higher than that in the first flush runoff. One of the affecting factors of the dissolved phosphorus was inferred to be the nature of the additives in engine oils or certain types of engines.
{"title":"Motor Vehicle Wash-off Water as a Source of Phosphorus in Roadway Runoff","authors":"K. Wada, R. Simpson, N. Kishimoto, N. Takei","doi":"10.2965/jwet.19-047","DOIUrl":"https://doi.org/10.2965/jwet.19-047","url":null,"abstract":"Algal water blooms in lakes or reservoirs are often caused by an enrichment of phosphorus. Depending on a bottom environment, dissolved phosphorus (phosphate) can be released into a water column from bottom sediments and accelerate algal and macrophyte nutrient dynamics. This study focuses on phosphorus pollutant loads in stormwater wash-off from roadways. Control of phosphorus discharge from non-point sources in urban areas is important for preventing water pollution. Sources of phosphorus in pollutant loads were explored by comparing first flush runoff with road dust/water mixture and vehicle wash-off water, where characteristics of the particulate and dissolved portions, and the relationship between road dust and wash-off from vehicles were also discussed. It was clear that the concentration of dissolved phosphorus in the vehicle wash-off water was higher than that in the first flush runoff. One of the affecting factors of the dissolved phosphorus was inferred to be the nature of the additives in engine oils or certain types of engines.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"18 1","pages":"9-16"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69262656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lake Tazawa in Akita Prefecture, Japan, is an acidic lake caused by the inflow of low-pH water from Tamagawa Hot Springs. Because of this anthropogenic acidification, many indigenous fish species and aquatic ecosystem have perished. Although several counter-measures such as artificial neutralization have been implemented against the acidic waters of Tamagawa River flowing into Lake Tazawa, the pH level of the lake remained low. Therefore, a bioassay evaluation of the low-pH lake water is necessary for ecosystem restoration. In this study, short-term chronic toxicity tests were applied to observe biological responses of three trophic levels of aquatic organisms using water samples of Lake Tazawa. As a result, Lake Tazawa water has toxic effect on all tested aquatic organisms. Especially, the fish embryo/larvae was directly affected by low-pH water, while algae and crustaceans were affected not only by low pH but other factors such as fluorine ion and metals. In order to improve the water quality management of Lake Tazawa for ecosystem restoration, further efforts are needed to reduce multiple toxic substances in addition to the pH neutralization of lake water.
{"title":"Short-term Chronic Toxicity Tests on Acidified Lake Tazawa Using Responses of Three Trophic Levels of Aquatic Organisms","authors":"Juhyun Kim, S. Masuda, S. Harada, O. Nishimura","doi":"10.2965/jwet.19-046","DOIUrl":"https://doi.org/10.2965/jwet.19-046","url":null,"abstract":"Lake Tazawa in Akita Prefecture, Japan, is an acidic lake caused by the inflow of low-pH water from Tamagawa Hot Springs. Because of this anthropogenic acidification, many indigenous fish species and aquatic ecosystem have perished. Although several counter-measures such as artificial neutralization have been implemented against the acidic waters of Tamagawa River flowing into Lake Tazawa, the pH level of the lake remained low. Therefore, a bioassay evaluation of the low-pH lake water is necessary for ecosystem restoration. In this study, short-term chronic toxicity tests were applied to observe biological responses of three trophic levels of aquatic organisms using water samples of Lake Tazawa. As a result, Lake Tazawa water has toxic effect on all tested aquatic organisms. Especially, the fish embryo/larvae was directly affected by low-pH water, while algae and crustaceans were affected not only by low pH but other factors such as fluorine ion and metals. In order to improve the water quality management of Lake Tazawa for ecosystem restoration, further efforts are needed to reduce multiple toxic substances in addition to the pH neutralization of lake water.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"1 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69263095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Puvaneswaree Nalaya, S. Wahid, Halmi Effendi Mohd. Izuan
Pentachlorophenol (PCP) has been used extensively in the wood preservation industry. It is highly persistent in the environment and toxic to living organisms. The present study investigated the effectiveness of an oil palm empty fruit bunch biochar (EFBB) pyrolyzed at 350, 550 and 650°C in adsorbing PCP as compared to a commercial activated carbon (AC). The ash content, surface area and aromaticity increased while the pore volume, cation exchange capacity, O/C and (O+N)/C molar ratios decreased as the pyrolysis temperature increased. Only the EFBB pyrolyzed at 350°C and the AC adsorbed the PCP while no PCP adsorption was observed on the EFBBs pyrolyzed at 550°C and 650°C. The Langmuir maximum adsorption capacity ( Q max ) values was 6.035 mg g −1 , and 126.582 mg g −1 for the 350°C EFBB and the AC, respectively. The higher porosity and more oxygenated functional groups of the EFBB pyrolyzed at 350°C EFBB could be the reason for its ability to adsorb the PCP compared to the other EFBBs. The high PCP sorption by the AC on the other hand, could be attributed to its high surface area and microporous structure.
{"title":"Characterization of Empty Fruit Bunch Biochar Pyrolyzed at Different Temperatures with Respect to Activated Carbon and their Sorption Capacities for Pentachlorophenol","authors":"Puvaneswaree Nalaya, S. Wahid, Halmi Effendi Mohd. Izuan","doi":"10.2965/jwet.20-013","DOIUrl":"https://doi.org/10.2965/jwet.20-013","url":null,"abstract":"Pentachlorophenol (PCP) has been used extensively in the wood preservation industry. It is highly persistent in the environment and toxic to living organisms. The present study investigated the effectiveness of an oil palm empty fruit bunch biochar (EFBB) pyrolyzed at 350, 550 and 650°C in adsorbing PCP as compared to a commercial activated carbon (AC). The ash content, surface area and aromaticity increased while the pore volume, cation exchange capacity, O/C and (O+N)/C molar ratios decreased as the pyrolysis temperature increased. Only the EFBB pyrolyzed at 350°C and the AC adsorbed the PCP while no PCP adsorption was observed on the EFBBs pyrolyzed at 550°C and 650°C. The Langmuir maximum adsorption capacity ( Q max ) values was 6.035 mg g −1 , and 126.582 mg g −1 for the 350°C EFBB and the AC, respectively. The higher porosity and more oxygenated functional groups of the EFBB pyrolyzed at 350°C EFBB could be the reason for its ability to adsorb the PCP compared to the other EFBBs. The high PCP sorption by the AC on the other hand, could be attributed to its high surface area and microporous structure.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69263507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Asaoka, Ryosuke Yoshiki, Yuki Haga, C. Matsumura, Akira Umehara, K. Takeda
Perfluoroalkyl substances (PFASs) such as perfluorocarboxylic acid (PFCAs) and perfluoroalkane sul fonates (PFSAs) are persistent, bioaccumulative, and toxic substances that are distributed worldwide. Here we investigated the current concentrations of PFASs in the surface sediments from the Seto Inland Sea, Japan. The concentrations of PFCAs in surface sediments from the Sea ranged from 0.05 to 0.67 ng g −1 . Perfluoroundecanoic acid (PFUnDA) was detected at all 15 sampling stations; its concentration was 0.05–0.24 ng g −1 . Perfluorohexanoic acid (PFHxA), which is used as an alternative to perfluorooctanoic acid (PFOA), was detected in Osaka Bay and Kii Channel. The contamination of PFCAs in the sediment from Osaka Bay and Kii Channel is shifting to PFHxA. In contrast, only perfluorooctanesulfonic acid (PFOS) was detected at the center part of the bays in the Sea. The sig nificant positive correlation between the PFCAs concentrations in the sediment and the sedimentation rates was observed in the Sea. Hence, the concentration of PFCAs in surface sediments from the Sea was controlled by the sedimentation rate.
全氟烷基物质(PFASs)，如全氟羧酸(PFCAs)和全氟烷烃磺酸盐(PFSAs)是分布在世界各地的持久性、生物蓄积性和有毒物质。本文研究了日本濑户内海表层沉积物中全氟辛烷磺酸的现状浓度。海洋表层沉积物中PFCAs的浓度范围为0.05 ~ 0.67 ng g−1。在所有15个采样站都检测到全氟癸酸;其浓度为0.05 ~ 0.24 ng g−1。在大阪湾和Kii海峡检测到用作全氟辛酸(PFOA)替代品的全氟己酸。大阪湾和启宜海峡沉积物中的PFCAs污染正向PFHxA转移。相比之下，只有在海湾的中心部分检测到全氟辛烷磺酸(PFOS)。海洋沉积物中PFCAs浓度与沉积速率呈显著正相关。因此，海洋表层沉积物中PFCAs的浓度受沉积速率的控制。
{"title":"Spatial Distribution of Perfluorinated Organic Compounds in Surface Marine Sediments from the Seto Inland Sea, Japan","authors":"S. Asaoka, Ryosuke Yoshiki, Yuki Haga, C. Matsumura, Akira Umehara, K. Takeda","doi":"10.2965/jwet.19-146","DOIUrl":"https://doi.org/10.2965/jwet.19-146","url":null,"abstract":"Perfluoroalkyl substances (PFASs) such as perfluorocarboxylic acid (PFCAs) and perfluoroalkane sul fonates (PFSAs) are persistent, bioaccumulative, and toxic substances that are distributed worldwide. Here we investigated the current concentrations of PFASs in the surface sediments from the Seto Inland Sea, Japan. The concentrations of PFCAs in surface sediments from the Sea ranged from 0.05 to 0.67 ng g −1 . Perfluoroundecanoic acid (PFUnDA) was detected at all 15 sampling stations; its concentration was 0.05–0.24 ng g −1 . Perfluorohexanoic acid (PFHxA), which is used as an alternative to perfluorooctanoic acid (PFOA), was detected in Osaka Bay and Kii Channel. The contamination of PFCAs in the sediment from Osaka Bay and Kii Channel is shifting to PFHxA. In contrast, only perfluorooctanesulfonic acid (PFOS) was detected at the center part of the bays in the Sea. The sig nificant positive correlation between the PFCAs concentrations in the sediment and the sedimentation rates was observed in the Sea. Hence, the concentration of PFCAs in surface sediments from the Sea was controlled by the sedimentation rate.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69262684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Determining the concentrations of dissolved and particulate selenium is of great importance, because it affects the toxicity, removal, recovery and reuse of selenium. For measurement, particulate selenium is usually separated from dissolved selenium by centrifugation or filtration. The reported relative centrifugation forces (rcf) used in separation are inconsistent and vary widely from 500 to 41,000 g. The 0.45 μm pore size filter is the most frequently used for the filtration. We systematically studied the effects of rcf and filter pore size on separation for typical environmental samples. We found that rcf ≥ 20,000 g and filter pore size ≤ 20 nm led to almost complete separation. The minimum rcf needed for separation could be predicted by Stokes’ law when the particulate selenium concentration was low (0.05 mg-Se/L), but could not be predicted when the particulate selenium concentration increased to ≥ 0.5 mg-Se/L probably due to aggregation of selenium nanoparticles at high concentrations. The presence of other particles (e.g., bacteria) also made the minimum rcf not predictable by Stokes’ law due to attachment of particulate selenium to bacteria. Therefore, the presence of other particles and the concentration of particulate selenium should be considered while choosing the appropriate centrifugation condition.
{"title":"Comparing Methods for Measuring Dissolved and Particulate Selenium in Water","authors":"Zhiming Zhang, Youneng Tang","doi":"10.2965/jwet.20-003","DOIUrl":"https://doi.org/10.2965/jwet.20-003","url":null,"abstract":"Determining the concentrations of dissolved and particulate selenium is of great importance, because it affects the toxicity, removal, recovery and reuse of selenium. For measurement, particulate selenium is usually separated from dissolved selenium by centrifugation or filtration. The reported relative centrifugation forces (rcf) used in separation are inconsistent and vary widely from 500 to 41,000 g. The 0.45 μm pore size filter is the most frequently used for the filtration. We systematically studied the effects of rcf and filter pore size on separation for typical environmental samples. We found that rcf ≥ 20,000 g and filter pore size ≤ 20 nm led to almost complete separation. The minimum rcf needed for separation could be predicted by Stokes’ law when the particulate selenium concentration was low (0.05 mg-Se/L), but could not be predicted when the particulate selenium concentration increased to ≥ 0.5 mg-Se/L probably due to aggregation of selenium nanoparticles at high concentrations. The presence of other particles (e.g., bacteria) also made the minimum rcf not predictable by Stokes’ law due to attachment of particulate selenium to bacteria. Therefore, the presence of other particles and the concentration of particulate selenium should be considered while choosing the appropriate centrifugation condition.","PeriodicalId":17480,"journal":{"name":"Journal of Water and Environment Technology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69262784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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