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1.
Dent J (Basel) ; 12(4)2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38667999

ABSTRACT

Poor oral health is an important concern for athletes, as it can affect both general health and athletic performance. The aim of this study is to investigate the effects of activity in chlorinated water on oral health in elite swimmers compared to non-swimming athletes. This cross-sectional study included 101 swimmers and 100 other athletes aged 13-26 years with a minimum training intensity of five hours per week (for at least the preceding two years). Oral health was assessed using the approximal plaque index (API) and the decayed/missing/filled teeth (DMFT) index. A DIAGNOcam was used to detect caries. Results show that swimmers were younger (15 years vs. 18 years), were more likely to be female (54% vs. 17%), and had a lower body mass index (20.1 kg/m2 vs. 21.9 kg/m2) and a lower juice consumption (9% vs. 24%). Non-swimmers had significantly more decayed, missing, or filled teeth due to caries and plaque. In conclusion, by comparing elite swimmers and athletes competing in different sports, we have shown that competitive swimmers have a lower incidence of dental caries and plaque. Further research is needed to test our findings and to understand this relationship in greater detail.

2.
Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 26(1cont): 182-198, jan.-jun. 2023.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1437900

ABSTRACT

O emprego de água na suinocultura global é o principal insumo e, conse- quentemente, elevado. Mas, para que o produtor obtenha resultados positivos técnicos e econômicos, precisa controlar que a água tenha a qualidade correta e seja ministrada na quantidade certa, seguindo as indicações da Instrução Normativa nº 113/2020 do Minis- tério da Agricultura, Pecuária e Abastecimento-MAPA, acerca da qualidade exigida deste elemento líquido, bem como a Instrução Normativa nº 357/2005 do CONAMA, relacio- nada ao uso e controle da água potável destinada ao consumo de humanos e animais. Uma forma de manter a qualidade da água potável na suinocultura é utilizando o dióxido de cloro (ClO2), eficaz numa ampla faixa de pH (4-10) na eliminação de vírus, bactérias e algas. Neste trabalho, objetiva-se apresentar índices zootécnicos da suinocultura parana- ense relacionados com a qualidade da água potável ­ pH, alcalinidade, dureza e cloração - e o reflexo dela na sanidade do animal evitando a poluição dos efluentes. O procedi- mento metodológico adotado é qualitativo com abordagem indutiva e técnica de pesquisa exploratória baseada em uma revisão de literatura. Da pesquisa bibliográfico-documental em sites de revistas científicas como a UNIPAR, a SCIELO, a Biblioteca Digital de Teses e Dissertações (BDTD), e sites do MAPA obteve-se um vasto material de consulta e apoio acerca do tema apresentado. Conclui-se que a qualidade da água na suinocultura deve ser monitorada por um profissional para que a produção seja lucrativa, zelando pelo bem- estar do rebanho, oferecendo-lhes água potável devidamente tratada, evitando a cloração indevida, dureza e alcalinidade fora do padrão exigido por lei.(AU)


The use of water in world pig farming is the main input and, consequently, high. In order for the producer to obtain positive technical and economic results, he will need to control that the water has the correct quality and that it is administered in the appropriate quantity, following the indications of Regulatory Instruction No. 113/2020 of the Ministry of Agriculture, Livestock and Supply-MAPA, on the required quality of this liquid element, as well as CONAMA Normative Instruction No. 357/2005, relating to the use and control of drinking water for human and animal consumption. One way to maintain the quality of drinking water in pig farming is by using chlorine dioxide (ClO2), effective in a wide range of pH (4-10) to eliminate viruses, bacteria and algae. In this work, the objective is to present zootechnical indices of swine production in Paraná related to the quality of drinking water - pH, alkalinity, hardness and chlorination - and its reflection on animal health, avoiding effluent contamination. The methodological procedure adopted is qualitative with an inductive approach and an exploratory research technique based on a literature review. From the bibliographical-documentary research on websites of scientific journals such as UNIPAR, SCIELO, the Digital Library of Theses and Dissertations (BDTD) and MAPA websites, a large amount of reference and support material on the topic presented was obtained. It is concluded that the quality of water in pig farming must be monitored by a professional so that production is profitable, ensuring the well-being of the herd, offering them duly treated drinking water, avoiding undue chlorination, hardness and alkalinity of the appropriate standard required by law.(AU)


El uso de agua en la porcicultura mundial es el principal insumo y, en consecuencia, elevado. Para que el productor obtenga resultados técnicos y económicos positivos, necesitará controlar que el agua tenga la calidad correcta y se administre en la cantidad adecuada, siguiendo las indicaciones de la Instrucción Normativa nº 113/2020 del Ministerio de Agricultura, Pecuaria y Suministro-MAPA, sobre la calidad exigida de este elemento líquido, así como la Instrucción Normativa del CONAMA n° 357/2005, relativa al uso y control del agua potable destinada al consumo humano y animal. Una forma de mantener la calidad del agua potable en la porcicultura es utilizando el dióxido de cloro (ClO2), eficaz en una amplia faja de pH (4-10) para eliminar virus, bacterias y algas. En este trabajo, el objetivo es presentar índices zootécnicos de la producción porcina en Paraná relacionados con la calidad del agua de bebida - pH, alcalinidad, dureza y cloración - y su reflejo en la salud del animal, evitando la contaminación de los efluentes. El procedimiento metodológico adoptado es cualitativo con un enfoque inductivo y una técnica de investigación exploratoria basada en una revisión de la literatura. De la investigación bibliográfico-documental en sitios web de revistas científicas como UNIPAR, SCIELO, la Biblioteca Digital de Tesis y Disertaciones (BDTD) y sitios web del MAPA, se obtuvo una gran cantidad de material de consulta y apoyo sobre el tema presentado. Se concluye que la calidad del agua en la porcicultura debe ser monitoreada por un profesional para que la producción sea rentable, velando por el bienestar del hato, ofreciéndoles agua potable debidamente tratada, evitando cloraciones indebidas, durezas y alcalinidades del padrón adecuado exigido por ley.(AU)


Subject(s)
Animals , Swine/physiology , Water Quality , Meat Industry/standards , Water Chlorination
3.
Eur J Ophthalmol ; 30(3): 430-438, 2020 May.
Article in English | MEDLINE | ID: mdl-32064920

ABSTRACT

PURPOSE: A prospective, open-label study in 20 professional swimmers evaluated the efficacy and safety of an ophthalmic solution containing crosslinked hyaluronic acid, coenzyme Q10, and vitamin E TPGS in releasing eye irritation and restoring ocular surface damages after prolonged exposure to chlorinated water. METHODS: Individually, one eye was instilled with the ophthalmic solution and the other used as a comparator. Eye drops were self-administered three times a day for 2 months. Tear film breakup time (primary endpoint), Schirmer I test, beating of eyelashes/min, tear osmolarity, corneal and conjunctival staining with fluorescein, Ocular Surface Disease Index questionnaire, subject satisfaction, visual acuity (secondary endpoints), and Efron Grading Scale were evaluated at screening/baseline (V1), week 1 (V2), week 2 (V3), week 4 (V4), and week 8 (V5). RESULTS: After 2 months, breakup time test significantly improved in the treated eyes (+1.67 s) compared to control (-3.00 s) (p = 0.0002). Corneal and conjunctival surfaces of treated eyes recovered significantly compared to control eyes when assessed by fluorescein staining (p < 0.0001), Ocular Surface Disease Index (p < 0.05), and visual analog scale (p = 0.0348) scores. Improvements were also observed with Schirmer I test, beating of eyelashes, and tear osmolarity, despite without statistical significance. Efron Grading Scale was consistent with the other tests. The ocular tolerability was excellent. CONCLUSION: The adequate combination of crosslinked hyaluronic acid, coenzyme Q10, and vitamin E TPGS, contained in the ophthalmic solution VisuXL®, has been shown to protect ocular surface from potential damages originating from prolonged exposure to chlorinated water. VisuXL may represent a compelling treatment in other situations beyond dry eye syndrome.


Subject(s)
Chloramines/adverse effects , Conjunctival Diseases/drug therapy , Corneal Diseases/drug therapy , Hyaluronic Acid/administration & dosage , Hyperemia/drug therapy , Ubiquinone/analogs & derivatives , Water Pollutants, Chemical/adverse effects , Administration, Ophthalmic , Adolescent , Adult , Conjunctival Diseases/chemically induced , Conjunctival Diseases/physiopathology , Corneal Diseases/chemically induced , Corneal Diseases/physiopathology , Cross-Linking Reagents , Disinfectants/adverse effects , Drug Combinations , Humans , Hyperemia/chemically induced , Hyperemia/physiopathology , Male , Ophthalmic Solutions , Osmolar Concentration , Prospective Studies , Quality of Life , Surveys and Questionnaires , Swimming Pools , Tears/chemistry , Tears/physiology , Ubiquinone/administration & dosage , Vitamin E/administration & dosage , Vitamins/administration & dosage , Young Adult
4.
J Dairy Sci ; 103(2): 1208-1214, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31837793

ABSTRACT

The objective of this study was to assess the effects of electrochemically activated drinking water (ECW) on milk chlorate, milk perchlorate, milk iodine, milk composition, milk fatty acid profile, and overall performance of dairy cows. Ten Red Danish cows in mid-lactation (203 ± 31 d in milk; average ± SD) were chosen from these 2 groups for intensive sampling. The treated group drank water with 4 ppm of ECW (29 mg/L of chlorate of Neuthox, Danish Clean Water A/S, Sønderborg, Denmark). The treatment lasted 60 consecutive days, with milk and water sampling on d 0, 30, and 60. Additionally, milk samples from both the control group and treated group were taken on d 90 to assess if any carry-over effect was present. Interactions between period and milk yield and somatic cell for the full group and period and milk fat content and milk urea nitrogen in the selected animals occurred. Milk yield was not significantly affected by treatments. Milk fat, milk fatty acid profile, chlorate, perchlorate, and iodine contents were not significantly different between treatments. Milk urea increased, whereas ß-hydroxybutyrate and somatic cell count decreased significantly in the treated groups. Results showed that at a dosing of 4 ppm of ECW, both chlorate and perchlorate concentrations in milk (<0.002 mg/kg) were low, and no deleterious effects on milk production or milk chemical composition were observed. These data can be of use when assessing the effects of ECW on milk and milk powder chlorate and perchlorate levels and provide a context for assessing the potential for influencing human health under the conditions prevailing on a commercial dairy farm.


Subject(s)
Drinking Water/chemistry , Milk/chemistry , 3-Hydroxybutyric Acid/analysis , Animals , Cattle , Chlorates/analysis , Denmark , Diet/veterinary , Electrochemical Techniques , Fatty Acids/analysis , Female , Iodine/analysis , Lactation , Perchlorates/analysis
5.
Polymers (Basel) ; 11(7)2019 Jul 08.
Article in English | MEDLINE | ID: mdl-31288492

ABSTRACT

The influence of chlorinated water on the global and local aging behavior of polypropylene (PP) was investigated for three differently stabilized PP grades consisting of the same PP base polymer. While one of the PP grades contained only a processing stabilizer (PP-S0), the other two were modified with a primary phenolic antioxidant (PP-S1) and a combination of a primary phenolic antioxidant and a hindered amine stabilizer (PP-S3). To study global aging effects, micro-sized specimens were pre-exposed to chlorinated water (5 mg/L free chlorine) at 60 °C for up to 750 h. Over the entire exposure period, significant material aging was detected by monitoring a continuous decrease in stabilizer content, oxidation induction temperature, mean molar mass, and mechanical strain at break. In terms of aging resistance and ultimate mechanical performance, PP-S1 was found to outperform the other two material formulations under these test conditions. Moreover, superimposed mechanical-environmental fatigue tests with cracked round bar specimens were carried out with the three PP grades in non-chlorinated (0 mg/L free chlorine) and chlorinated (5 mg/L free chlorine) water at 80 °C and 95 °C to study local crack tip aging effects. While the fatigue crack growth resistance substantially deteriorated for all three materials in chlorinated water, a significantly stronger effect was found for the higher temperature, with crack growth rates at a given stress intensity factor range in chlorinated water being ca. 30 to 50 times faster than in non-chlorinated water, depending on the material. Molar mass measurements of material samples taken from various positions of the tested CRB specimens provided clear evidence of enhanced local crack tip aging due to the chlorinated water environment.

6.
Polymers (Basel) ; 11(6)2019 Jun 04.
Article in English | MEDLINE | ID: mdl-31167458

ABSTRACT

Polypropylene random copolymers (PP-R) are common materials for pressurized hot water pipes. In many pipe systems, potable water is disinfected by chlorine to prevent waterborne diseases. This paper deals with hot chlorinated water induced aging of two PP-R grades with varying morphology. One material had a conventional monoclinic α crystal form (PP-Rα), whereas the other was explicitly beta-nucleated resulting in a trigonal ß crystal form with a fine spherulite structure (PP-Rß). Micro-sized specimens with a thickness of 100 µm were used for aging experiments at 60 °C in chlorinated water with 5 mg/L free chlorine, and aging indicators were monitored for exposure times of up to 2000 h. On the other hand, superimposed mechanical-environmental tests were carried out by using cracked round bar specimens with a diameter of 14 mm to determine the fatigue crack growth (FCG) resistance of both PP-R grades at 60 °C in non-chlorinated and chlorinated water. PP-Rß was found to outperform PP-Rα with an about 30% higher time-to-embrittlement value of 2000 h. Furthermore, PP-Rß exhibited an enhanced FCG resistance in both non-chlorinated and chlorinated water. The effect of chlorine content on the deterioration of the FCG resistances was significantly more pronounced for PP-Rα.

7.
Ann Agric Environ Med ; 25(4): 651-655, 2018 Dec 20.
Article in English | MEDLINE | ID: mdl-30586974

ABSTRACT

Indoor swimming pools can be used all year round and serve for one of the most popular sport pursued for recreation. The positive effect of swimming arises in particular from the involvement of all the muscles of the body, decreasing the burden on the joints, as well as functional improvement of both the lungs and heart. Chlorine is typically used to disinfect swimming pool water and as a result the changes that take place lead to the formation of by-products, such as monochloramines (NH2Cl), dichloramines (NH2Cl2) i trichloramines (NH2Cl3), trihalogenometans (THM) or haloacetic acid (HAA). The highest concentration of these substances is just above the water surface and they may cause irritation of skin, eyes and mucosa of the respiratory tract. The toxic effect of high chlorine concentration and its side-products on the respiratory system is known, but the effect of low concentrations of these compounds is still not fully determined. Recent studies suggest that development of allergic diseases among swimmers may be increased by epithelial disorders driven by airway barrier dysfunction caused by chlorine irritation. Swimming in chlorinated water may be linked to symptoms of bronchial hyperreactivity, asthma and rhinitis especially in children, elite swimmers and employees of indoor swimming pools. Hypersensivity pneumonitis related to the use of swimming pools may manifest as a swimming pool or sauna user lung, most commonly caused by water polluting pathogens. The article summarizes recent data concerning the influence of chlorinated water on the development of allergic diseases.


Subject(s)
Chlorine/adverse effects , Disinfectants/adverse effects , Hypersensitivity/etiology , Water/analysis , Halogenation , Humans , Hypersensitivity/immunology , Swimming , Water/adverse effects
8.
J Pharm Biomed Anal ; 152: 137-142, 2018 Apr 15.
Article in English | MEDLINE | ID: mdl-29414005

ABSTRACT

The study aims the development and validation of a LC-MS/MS method for the identification and quantification of benzodiazepines and zolpidem in nails as alternative keratinized matrix to hair in long-term monitoring of anxiolytic and hypnotic drugs. Both fingernail and toenail samples (1-2 mm) were collected by clipping the excess overhang of the nail from volunteers and from postmortem cases. They were washed twice with organic solvents, dried under nitrogen stream, pulverized, immersed in a methanol solution (internal standard: diazepam-D5) and sonicated up to two hours. The solution was then direct injected in the LC-MS/MS system. Mass spectrometry was set in MRM mode, selecting two transitions for each substance. 32 analytes among benzodiazepines, metabolites and hypnotics were included in the list. The method fulfilled the internationally required criteria for validation. Limits of detection ranged from 0.03 pg/mg (zolpidem) to 13.1 pg/mg (bromazepam). 9 subjects under therapy were positive at 7 different benzodiazepines and/or metabolites (lorazepam, desalkylflurazepam, bromazepam, diazepam, alprazolam, lormetazepam and prazepam), while 5 molecules were measured in 4 postmortem cases (diazepam, desmethyldiazepam, delorazepam, 7-aminoclonazepam and zolpidem). In vitro experiments on eight authentic samples suggested that benzodiazepines in nails are influenced by the prolonged exposure to chlorinated water.


Subject(s)
Benzodiazepines/chemistry , Chlorine/adverse effects , Nails/chemistry , Pyridines/chemistry , Water/adverse effects , Bromazepam/chemistry , Chromatography, Liquid/methods , Diazepam/chemistry , Female , Forensic Toxicology/methods , Humans , Limit of Detection , Male , Tandem Mass Spectrometry/methods , Zolpidem
9.
Polymers (Basel) ; 10(8)2018 Jul 27.
Article in English | MEDLINE | ID: mdl-30960754

ABSTRACT

To assess the potential use of polyamide (PA) for solar-thermal systems applications, the effect of water with varying chlorine content on the fatigue crack growth (FCG) resistance of two PA formulations differing in their stabilizer packages was investigated at 80 °C. A commercial PA containing 30 wt % glass fibers and a standard stabilization package (PA-0) was used as the reference material. For the other formulation, the reference material PA-0 was compounded with two additional stabilizers (PA-S1). Keeping the specimen geometry and initial loading conditions the same, the total number of cycles to ultimate specimen failure was found to be reduced with an increase in chlorine content for both materials. As to the effect of the chlorine content on crack growth kinetics, the most pronounced effect in enhancing the crack growth rates or decreasing the FCG resistance was determined between 0 ppm and 1 ppm chlorine content. When comparing the relative change of FCG resistance in chlorinated water (10 ppm) to the FCG resistance in non-chlorinated water (0 ppm), the additional stabilization in the material PA-S1 appears beneficial over the stabilization in the reference material PA-0.

10.
Forensic Sci Int ; 278: 217-220, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28750304

ABSTRACT

INTRODUCTION: An in vitro study on authentic positive samples was carried out, aiming the evaluation of the effect of chlorinated water on benzodiazepines in hair. Two subjects exposed to chlorinated water for several consecutive times were also investigated. METHOD: Seven hair samples collected from autopsy cases, previously tested positive for benzodiazepines, were washed with dichloromethane and methanol. They were longitudinally divided in six aliquots of about 30mg. An aliquot was processed without treatment while other five ones were soaked in chlorinated water (0.1% sodium dichloroisocyanurate and 0,1M sulfuric acid at pH 5.5) for 4, 20, 24 and 30h respectively. Hair samples were then processed following a fully validated and previously published method. Briefly hair samples were sonicated in 600 microliters methanol containing halazepam (IS) up to two hours. Ten microliters were injected in a liquid chromatographic tandem mass spectrometric (LC-MS/MS) system. Analytes were eluted from a C18 reversed-phased column. Two transitions on multiple reaction monitoring and positive ionization mode were monitored for each compound. RESULT AND DISCUSSIONS: Six compounds among benzodiazepines and metabolites were identified and quantified in the seven hair samples: diazepam (575pg/mg), desmethyldiazepam (562pg/mg), chlordesmethyldiazepam (173pg/mg), desalkylflurazepam (320pg/mg), clonazepam (three cases-195, 119 and 111pg/mg respectively), lormetazepam (two cases-182 and 416pg/mg respectively). Traces of 7-aminoclonazepam were identified into 2 samples. Stability of benzodiazepines in water was evaluated by soaking an aliquot of hair for up to 30h in deionized water. No significant degradation was observed. Samples soaked in chlorinated water showed considerable decreasing from the initial concentration even after the 4-h treatment: the fastest degradation was provided by clonazepam that showed a 61% loss. The greatest loss was measured for diazepam (86% loss after 30-h soaking). CONCLUSION: To the best of our knowledge this is the first in vitro study that evaluated benzodiazepines stability in hair after prolonged exposure to chlorinated water. The results showed that the longer the exposure the higher the degradation. Prolonged exposure to chlorinated water and sunlight must be always taken into account as possible causes of false negative results.


Subject(s)
Benzodiazepines/analysis , Chlorine/chemistry , Disinfectants/chemistry , Drug Stability , Hair/chemistry , Water/chemistry , Child, Preschool , Chlorine/analysis , Chromatography, Liquid , Disinfectants/analysis , Female , Humans , Male , Swimming Pools , Tandem Mass Spectrometry
11.
Environ Toxicol ; 31(8): 1009-16, 2016 Aug.
Article in English | MEDLINE | ID: mdl-25640707

ABSTRACT

Trihalomethanes (THMs) are disinfection byproducts found in chlorinated water, and are associated with several different kinds of cancer in human populations and experimental animal models. Metabolism of THMs proceeds through enzymes such as GSTT1 and CYP2E1 and gives rise to reactive intermediates, which form the basis for their toxic activities. The aim of this study was to assess the mitochondrial dysfunction caused by THMs at low levels, and the resulting hepatic histological and biochemical changes in the mouse. Male ICR mice were administered with two THMs: dibromochloromethane (DBCM) and bromodichloromethane (BDCM); once daily, by gavage, to a total of four administrations. Animals were sacrificed four weeks after DBCM and BDCM administrations. Blood biochemistry was performed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TB), albumin (Alb), total protein (TP), creatinine, and urea. Animals exposed to DBCM and BDCM showed elevated ALT and TB levels (p < 0.05) as compared with controls. Histological analysis confirmed the presence of vacuolar degenerescence and a multifocal necrotizing hepatitis in 33% of animals (n = 2). Mitochondrial analysis showed that THMs reduced mitochondrial bioenergetic activity (succinate dehydrogenase (SQR), cytochrome c oxidase (COX), and ATP synthase) and increased oxidative stress (glutathione S-transferase (GST)) in hepatic tissues (p < 0.05). These results add detail to the current understanding of the mechanisms underlying THM-induced toxicity, supporting the role of mitochondrial dysfunction and oxidative stress in liver toxicity caused by DBCM and BDCM. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1009-1016, 2016.


Subject(s)
Oxidative Stress/drug effects , Trihalomethanes/toxicity , Water Pollutants, Chemical/toxicity , Alanine Transaminase/blood , Animals , Chemical and Drug Induced Liver Injury/blood , Disinfection , Humans , Liver/drug effects , Liver/metabolism , Male , Mice , Mice, Inbred ICR , Mitochondria, Liver/drug effects , Mitochondria, Liver/metabolism , Water Purification
12.
Environ Health Toxicol ; 26: e2011003, 2011.
Article in English | MEDLINE | ID: mdl-22125764

ABSTRACT

OBJECTIVES: N-Nitrosodimethylamine (NDMA) is classified as a probable human carcinogen by the United States Environmental Protection Agency (US EPA) and is formed during the chlorination of municipal drinking water. In this study, selected nitrosamines were measured in chlorinated drinking water collected from Chuncheon, Kangwon-do, Republic of Korea, and a risk assessment for NDMA was conducted. METHODS: Twelve water samples were collected from 2 treatment plants and 10 household taps. Samples were analyzed for 6 nitrosamines via solid-phase extraction cleanup followed by conversion to dansyl derivatives and high-performance liquid chromatography-fluorescence detection (HPLC-FLD). Considering the dietary patterns of Korean people and the concentration change of NDMA by boiling, a carcinogenic risk assessment from ingestion exposure was conducted following the US EPA guidelines. RESULTS: NDMA concentrations ranged between 26.1 and 112.0 ng/L. NDMA in water was found to be thermally stable, and thus its concentration at the end of boiling was greater than before thermal treatment owing to the decrease in water volume. The estimated excess lifetime carcinogenic risk exceeded the regulatory baseline risk of 10(-5). CONCLUSIONS: This result suggests that more extensive studies need to be conducted on nitrosamine concentration distributions over the country and the source of relatively high nitrosamine concentrations.

13.
Article in English | WPRIM (Western Pacific) | ID: wpr-101237

ABSTRACT

OBJECTIVES: N-Nitrosodimethylamine (NDMA) is classified as a probable human carcinogen by the United States Environmental Protection Agency (US EPA) and is formed during the chlorination of municipal drinking water. In this study, selected nitrosamines were measured in chlorinated drinking water collected from Chuncheon, Kangwon-do, Republic of Korea, and a risk assessment for NDMA was conducted. METHODS: Twelve water samples were collected from 2 treatment plants and 10 household taps. Samples were analyzed for 6 nitrosamines via solid-phase extraction cleanup followed by conversion to dansyl derivatives and high-performance liquid chromatography-fluorescence detection (HPLC-FLD). Considering the dietary patterns of Korean people and the concentration change of NDMA by boiling, a carcinogenic risk assessment from ingestion exposure was conducted following the US EPA guidelines. RESULTS: NDMA concentrations ranged between 26.1 and 112.0 ng/L. NDMA in water was found to be thermally stable, and thus its concentration at the end of boiling was greater than before thermal treatment owing to the decrease in water volume. The estimated excess lifetime carcinogenic risk exceeded the regulatory baseline risk of 10(-5). CONCLUSIONS: This result suggests that more extensive studies need to be conducted on nitrosamine concentration distributions over the country and the source of relatively high nitrosamine concentrations.


Subject(s)
Humans , Dimethylnitrosamine , Drinking , Drinking Water , Eating , Family Characteristics , Halogenation , Nitrosamines , Oligopeptides , Phosphatidylcholines , Republic of Korea , Risk Assessment , United States Environmental Protection Agency , Water
14.
J Food Prot ; 60(10): 1230-1234, 1997 Oct.
Article in English | MEDLINE | ID: mdl-31207719

ABSTRACT

Microbiological quality in grated beetroots was studied. The vegetable was washed with cold water (8°C) or with chlorinated water (8°C and 252 mg active chlorine per liter water) and packaged in trays wrapped in high permeability film (PVC). Storage temperatures were 0, 4, and 20°C. Aerobic count colonies (ACC), fungi and yeasts, and lactose fermentative bacteria were determined. Representative colonies were identified. The results obtained showed that the treatment with chlorinated water caused significant decreases (P < 0.05) in the initial yeast counts and total aerobic counts. Treatment with cold chlorinated water significantly decreased the yeast counts and PCA counts after 3 days at 0 and 4°C. The change to 20°C caused significantly increased (P < 0.05) PCA counts in the grated beetroots (107 to 108 CFU/g). The microorganisms predominant among the isolates from fresh grated beetroots were gram negative bacteria (80%) and yeasts. None of the trays with grated beetroots contained molds. Some of the bacteria identified were Micrococcus luteus , Acinetobacter spp., Corynebacterium spp., and Enterobacteriaceae .

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