DOCSLIB.ORG

Evaluating Analytical Methods for Detecting Unknown Chemicals in Recycled Water

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

PROJECT NO. 4992 Evaluating Analytical Methods for Detecting Unknown Chemicals in Recycled Water Evaluating Analytical Methods for Detecting Unknown Chemicals in Recycled Water Prepared by: Keith A. Maruya Charles S. Wong Southern California Coastal Water Research Project Authority 2020 The Water Research Foundation (WRF) is a nonprofit (501c3) organization which provides a unified source for One Water research and a strong presence in relationships with partner organizations, government and regulatory agencies, and Congress. The foundation conducts research in all areas of drinking water, wastewater, stormwater, and water reuse. The Water Research Foundation’s research portfolio is valued at over $700 million. The Foundation plays an important role in the translation and dissemination of applied research, technology demonstration, and education, through creation of research‐based educational tools and technology exchange opportunities. WRF serves as a leader and model for collaboration across the water industry and its materials are used to inform policymakers and the public on the science, economic value, and environmental benefits of using and recovering resources found in water, as well as the feasibility of implementing new technologies. For more information, contact: The Water Research Foundation Alexandria, VA Office Denver, CO Office 1199 North Fairfax Street, Suite 900 6666 West Quincy Avenue Alexandria, VA 22314‐1445 Denver, Colorado 80235‐3098 Tel: 571.384.2100 Tel: 303.347.6100 www.waterrf.org [email protected] ©Copyright 2020 by The Water Research Foundation. All rights reserved. Permission to copy must be obtained from The Water Research Foundation. WRF ISBN: 978‐1‐60573‐503‐0 WRF Project Number: 4992 This report was prepared by the organization(s) named below as an account of work sponsored by The Water Research Foundation. Neither The Water Research Foundation, members of The Water Research Foundation, the organization(s) named below, nor any person acting on their behalf: (a) makes any warranty, express or implied, with respect to the use of any information, apparatus, method, or process disclosed in this report or that such use may not infringe on privately owned rights; or (b) assumes any liabilities with respect to the use of, or for damages resulting from the use of, any information, apparatus, method, or process disclosed in this report. Southern California Coastal Water Research Project Authority Funding has been provided in full or in part through an agreement with the California State Water Resources Control Board. The California Water Quality, Supply, and Infrastructure Improvement Act of 2014 (Proposition 1) authorizes $7.545 billion in general obligation bonds to fund ecosystems and watershed protection and restoration, water supply infrastructure projects, including surface and groundwater storage, and drinking water protection. The contents of this document do not necessarily reflect the views and policies of the foregoing, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. This document was reviewed by a panel of independent experts selected by The Water Research Foundation. Mention of trade names or commercial products or services does not constitute endorsement or recommendations for use. Similarly, omission of products or trade names indicates nothing concerning The Water Research Foundation's positions regarding product effectiveness or applicability. ii The Water Research Foundation Acknowledgments Research Team Principal Investigator: Keith A. Maruya, Ph.D. Southern California Coastal Water Research Project Authority Project Team: Charles S. Wong, Ph.D. Southern California Coastal Water Research Project Authority Expert Reviewers Eunha Hoh, Ph.D. San Diego State University Shane Snyder, Ph.D. NTU Singapore Coordinating Committee Robert Brownwood Division of Drinking Water, State Water Resources Control Board James Crook, Ph.D., P.E. Environmental Consultant Adam Olivieri, Dr.PH, P.E. EOA Claire Waggoner Division of Water Quality, State Water Resources Control Board Water Research Foundation Staff John Albert, MPA Chief Research Officer Justin Mattingly Research Manager Julie Minton Research Program Leader Evaluating Analytical Methods for Detecting Unknown Chemicals in Recycled Water iii Abstract and Benefits Abstract: This report provides a synopsis of the current state‐of‐the‐science for analytical methods to identify and measure unknown trace organic compounds (TOrCs) in recycled water. It proposes is an integrated framework that includes targeted analysis of known contaminants, as well as semi‐ and non‐targeted analysis of unknown contaminants by both instrumental methods and by bioassays, along with the advantages and limitations of each approach. A research plan is also presented to evaluate the utility of using these strategies for identifying unknown TOrCs. Finally, a communications strategy is outlined for regulators, managers, and the general public with regards to monitoring for unknown TOrCs using the methods discussed. Benefits: Demonstrates that recycled water can contain a plethora of known and unknown TOrCs that affect water quality and potential reuse of this resource. Demonstrates that a variety of instrumental methods exist for both targeted and semi‐/ non‐targeted analysis of TOrCs, each with advantages and limitations. Demonstrates that an integrated approach that uses targeted analysis, instrumental semi‐/ non‐targeted analysis, and bioassays as appropriate can address unknown TOrCs well. Demonstrates that the proposed research plan evaluates whether candidate analytical methods can correctly identify model “unknown” compounds. Demonstrates that later phases of the proposed research determine if indicator compounds can be used to signal the presence of TOrCs. Demonstrates that accuracy, transparency, and timeliness are crucial for disseminating results around unknown TOrCs to stakeholders: regulators, customers, and the general public. Keywords: Recycled water, trace organic compounds, targeted analysis, non‐targeted analysis, bioassays, potable reuse. iv The Water Research Foundation Contents Acknowledgments ........................................................................................................................................ iii Abstract and Benefits ................................................................................................................................... iv Tables ........................................................................................................................................................... vii Figures ......................................................................................................................................................... viii Acronyms and Abbreviations ........................................................................................................................ ix Executive Summary ....................................................................................................................................... xi Chapter 1: Introduction ............................................................................................................................... 1 1.1 Study Goals ......................................................................................................................... 1 1.2 Problem Statement ............................................................................................................. 1 1.3 Scope and Organization ...................................................................................................... 1 1.4 Definitions ........................................................................................................................... 2 Chapter 2: Analytical Methods for Low Molecular Weight Unknown Compounds in Waters .................. 5 2.1 Developing Analytical Methods for Water Quality Monitoring .......................................... 5 2.2 Sample Handling and Processing ........................................................................................ 5 2.3 Analytical Methods for Identifying Known and Unknown Contaminants .......................... 7 2.3.1 Targeted Methods ................................................................................................. 7 2.3.2 Semi‐ and Non‐Targeted Methods ........................................................................ 8 2.4 Tiered Monitoring Strategy for Recycled Water ............................................................... 10 2.4.1 Tier 1: Bulk Water Analysis for Surrogates of TOrCs ............................................... 11 2.4.2 Tier 2: Targeted Chemical Analysis for Indicator TOrCs........................................... 11 2.4.3 Tier 3: Instrumental Non‐Targeted Analysis ............................................................ 12 2.4.4 Tier 3: Bioassay Directed Identification of Unknowns ............................................. 15 2.5 Interpretation of Analytical Results for Unknown Contaminants .................................... 15 2.6 Data Support Tools for Non‐Targeted Analysis ................................................................ 17 2.7 Frequency of Monitoring .................................................................................................. 17 Chapter 3: Proposed Research Plan .........................................................................................................
Recommended publications
  • Report of the Advisory Group to Recommend Priorities for the IARC Monographs During 2020–2024

    Report of the Advisory Group to Recommend Priorities for the IARC Monographs During 2020–2024

    IARC Monographs on the Identification of Carcinogenic Hazards to Humans Report of the Advisory Group to Recommend Priorities for the IARC Monographs during 2020–2024 Report of the Advisory Group to Recommend Priorities for the IARC Monographs during 2020–2024 CONTENTS Introduction ................................................................................................................................... 1 Acetaldehyde (CAS No. 75-07-0) ................................................................................................. 3 Acrolein (CAS No. 107-02-8) ....................................................................................................... 4 Acrylamide (CAS No. 79-06-1) .................................................................................................... 5 Acrylonitrile (CAS No. 107-13-1) ................................................................................................ 6 Aflatoxins (CAS No. 1402-68-2) .................................................................................................. 8 Air pollutants and underlying mechanisms for breast cancer ....................................................... 9 Airborne gram-negative bacterial endotoxins ............................................................................. 10 Alachlor (chloroacetanilide herbicide) (CAS No. 15972-60-8) .................................................. 10 Aluminium (CAS No. 7429-90-5) .............................................................................................. 11
  • Disinfection Byproducts in Chlorinated Drinking Water

    Disinfection Byproducts in Chlorinated Drinking Water

    International Journal of Water and Wastewater Treatment SciO p Forschene n HUB for Sc i e n t i f i c R e s e a r c h ISSN 2381-5299 | Open Access RESEARCH ARTICLE Volume 4 - Issue 2 | DOI: http://dx.doi.org/10.16966/2381-5299.156 Disinfection Byproducts in Chlorinated Drinking Water Malia Vester1, Hany F Sobhi2 and Mintesinot Jiru1* 1Department of Natural Sciences, Coppin State University, Maryland, USA 2Center for Organic Synthesis, Department of Natural Sciences, Coppin State University, Maryland, USA *Corresponding author: Mintesinot Jiru, Department of Natural Sciences, Coppin State University, Maryland, USA, Tel: 410-951-4139; E-mail: [email protected] Received: 07 Jul, 2018 | Accepted: 14 Nov, 2018 | Published: 20 Nov, 2018 Citation: Vester M, Sobhi HF, Jiru M (2018) Disinfection Byproducts in Chlorinated Drinking Water. Int J Water Wastewater Treat 4(2): dx.doi. org/10.16966/2381-5299.156 Copyright: © Vester M, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract Trihalomethanes (THMs) are disinfection byproducts formed through the reaction of chlorine and organic matter. There are four forms of Trihalomethanes: chloroform, bromoform, dibromochloromethane and bromodichloromethane. Studies have shown that chloroform, a principal disinfection byproduct, is carcinogenic in rodents. Although the presence of these hazardous materials are constantly being monitored by Water Treatment Plant and the Environmental Protection Agency (EPA), they continue to be present at an unpredictable levels and the full effects of these byproducts are not fully understood.
  • Organic Matter Composition Related to Methane Ebullitive Flux of an Urban Coastal Lagoon, Southeastern Brazil

    Organic Matter Composition Related to Methane Ebullitive Flux of an Urban Coastal Lagoon, Southeastern Brazil

    Quim. Nova, Vol. 42, No. 6, 619-627, 2019 http://dx.doi.org/10.21577/0100-4042.20170373 ORGANIC MATTER COMPOSITION RELATED TO METHANE EBULLITIVE FLUX OF AN URBAN COASTAL LAGOON, SOUTHEASTERN BRAZIL Alessandra da Fonseca Vianaa,*, , Marco Aurélio dos Santosa, Marcelo Corrêa Bernardesb and Marcelo Amorima aInstituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa de Engenharia, Universidade Federal do Rio de Janeiro, 21941-450 Rio de Janeiro – RJ, Brasil b Departamento de Geoquímica, Universidade Federal Fluminense, 24020-141 Niterói – RJ, Brasil Artigo Recebido em 25/04/2019; aceito em 04/06/2019; publicado na web em 26/06/2019 In 2016, Brazil emitted 18.25 Tg of methane. Some of these emissions occur through continental aquatic ecosystems, locations of fate and accumulation of organic and inorganic matter. Thus, the aim of this study is to evaluate the origin of organic matter in Rodrigo de Freitas Lagoon, an eutrophic, coastal and chocked lagoon in Rio de Janeiro, Brazil, through the determination of n-alkanes and sterols compounds in the upper two centimeters of sediment and compare these data with methane ebullitive flux. The concentrations of n-alkanes varied between 2.43 and 25.82 µg g-1. C29 was predominant compound in most sites, but also with important petrogenic source evidenced by the occurrence of Unresolved Complex Misture. The total concentration of sterols ranged from 2.76 to 56.01 µg g-1. β-sitostanol was the most abundant compound and coprostanol was the most relevant at the sites under -2 -1 -2 -1 influence of domestic effluents. 4CH ebullitive flux averaged 199 mg m d in the dry period and 9.3 mg m d during the wet season.
  • Study on the Derivatization Process Using NO-Bis-(Trimethylsilyl)

    Study on the Derivatization Process Using NO-Bis-(Trimethylsilyl)

    World Academy of Science, Engineering and Technology International Journal of Chemical and Molecular Engineering Vol:4, No:1, 2010 Study on the Derivatization Process Using N-O-bis-(trimethylsilyl)-trifluoroacetamide, N-(tert-butyldimethylsilyl)-N-methyltrifluoroace tamide, Trimethylsilydiazomethane for the Determination of Fecal Sterols by Gas Chromatography-Mass Spectrometry Jingming Wu, Ruikang Hu, Junqi Yue, Zhaoguang Yang, and Lifeng Zhang Abstract—Fecal sterol has been proposed as a chemical indicator I. INTRODUCTION of human fecal pollution even when fecal coliform populations have O protect public health, it is important to monitor drinking diminished due to water chlorination or toxic effects of industrial effluents. This paper describes an improved derivatization procedure Twater and recreational water bodies to ensure the for simultaneous determination of four fecal sterols including pathogens are not present. Recently, various chemical coprostanol, epicholestanol, cholesterol and cholestanol using gas compounds have been used for identifying human sewage chromatography-mass spectrometry (GC-MS), via optimization study contamination in water bodies [1-3]. Coprostanol, formed on silylation procedures using N-O-bis during catabolism of cholesterol by indigenous bacteria present (trimethylsilyl)-trifluoroacetamide (BSTFA), and in the gut of humans or animals, is the primary fecal sterol N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA), which lead to the formation of trimethylsilyl (TMS) and detected in the domestic wastewater or sediment samples [1-3]. tert-butyldimethylsilyl (TBS) derivatives, respectively. Two It has been proposed as a chemical indicator of human fecal derivatization processes of injection-port derivatization and water bath pollution even when fecal coliform populations have derivatization (60 oC, 1h) were inspected and compared.
  • Potassium Bromate

    Potassium Bromate

    POTASSIUM BROMATE VWR International, Pty Ltd Chemwatch: 1484 Issue Date: 25/01/2013 Version No: 6.1.1.1 Print Date: 10/12/2013 Safety Data Sheet according to WHS and ADG requirements S.GHS.AUS.EN SECTION 1 IDENTIFICATION OF THE SUBSTANCE / MIXTURE AND OF THE COMPANY / UNDERTAKING Product Identifier Product name POTASSIUM BROMATE Chemical Name potassium bromate Synonyms Br-K-O3, KBrO3, bromic acid potassium salt Proper shipping name POTASSIUM BROMATE Chemical formula BrHO3.K Other means of identification Not Available CAS number 7758-01-2 Relevant identified uses of the substance or mixture and uses advised against Used as laboratory reagent, oxidising agent, permanent wave compound, maturing agent in flour, dough conditioner and food additive. Bromate is Relevant identified uses converted to bromide in the baking or cooking process, but the levels are not in excess of the natural bromide content of many natural foods., Note: Food additive uses restricted as to proportions used., [~Intermediate ~] Details of the supplier of the safety data sheet Registered company name VWR International, Pty Ltd Unit 1/31 Archimedes Place 4172 QLD Address Australia Telephone 61 7 3009 4100 ; 1300 727 696 Fax 61 7 3009 4199 ; 1300 135 123 Website http://au.vwr.com Email [email protected] Emergency telephone number Association / Organisation Not Available Emergency telephone numbers 61 7 3009 4100 ; 1300 727 696 Other emergency telephone numbers 61 7 3009 4100 ; 1300 727 696 SECTION 2 HAZARDS IDENTIFICATION Classification of the substance or mixture HAZARDOUS CHEMICAL. DANGEROUS GOODS. According to the Model WHS Regulations and the ADG Code.
  • Abstract Measurement and Analysis of Bromate Ion

    Abstract Measurement and Analysis of Bromate Ion

    ABSTRACT MEASUREMENT AND ANALYSIS OF BROMATE ION REDUCTION IN SYNTHETIC GASTRIC JUICE by Jason Dimitrius Keith Bromate ion is a possible carcinogen that is regulated by the US EPA at a Maximum Contamination Level (MCL) of 10 µg/L in drinking water. In order to propose an improved scientifically appropriate bromate ion MCL, a more rigorous scientific methodology is needed for determining low level dose health risks. The objectives of this research project were to measure bromate ion with oxidizing and/or reducing agents typically ingested in foods and drinking water. The loss of bromate ion in HCl is too slow for significant reduction in the stomach. -5 Addition of 10 M H2S, a gastric juice component, decreases the half-life from 153 to 14 minutes. The ingested reducing agents iodide ion, nitrite ion, and iron(II) decrease the lifetime of bromate ion in the stomach. Chlorine, monochloramine, and iron(III) have little actual effect on the lifetime of bromate ion. The measured rates and chemical details of the reactions are discussed. MEASUREMENT AND ANALYSIS OF BROMATE ION REDUCTION IN SYNTHETIC GASTRIC JUICE A Thesis Submitted to the faculty of Miami University in partial fulfillment of the requirements for the degree of Master of Science Department of Chemistry by Jason Dimitrius Keith Miami University Oxford, Ohio 2005 Co-Advisor________________ (Dr. Gilbert Gordon) Co-Advisor________________ (Dr. Gilbert E. Pacey) Reader_________________ (Dr. Michael W. Crowder) Reader_________________ (Dr. Hongcai Zhou) TABLE OF CONTENTS TABLE OF CONTENTS ii LIST OF TABLES iii LIST OF FIGURES iv ACKNOWLEDGEMENTS v INTRODUCTION 1 Bromate Ion Chemistry and Human Toxicology 1 Prior Analytical Methodology 6 Objectives 7 METHOD DEVELOPMENT AND ESTABLISHMENT OF PROTOCOLS 7 Solution Preparation 7 Preparation and Measurement of Stock HOCl/ Cl2 and ClNH2 Solutions 11 Measurement of Iron(II) and Iron(III) in Solution 12 Instrumentation.
  • Aniline and Aniline Hydrochloride

    Aniline and Aniline Hydrochloride

    SOME AROMATIC AMINES AND RELATED COMPOUNDS VOLUME 127 This publication represents the views and expert opinions of an IARC Working Group on the Identification of Carcinogenic Hazards to Humans, which met remotely, 25 May–12 June 2020 LYON, FRANCE - 2021 IARC MONOGRAPHS ON THE IDENTIFICATION OF CARCINOGENIC HAZARDS TO HUMANS ANILINE AND ANILINE HYDROCHLORIDE 1. Exposure Characterization 1.1.2 Structural and molecular formulae, and relative molecular mass 1.1 Identification of the agent (a) Aniline 1.1.1 Nomenclature NH2 (a) Aniline Chem. Abstr. Serv. Reg. No.: 62-53-3 EC No.: 200-539-3 Molecular formula: C H N IUPAC systematic name: aniline 6 7 Relative molecular mass: 93.13 (NCBI, 2020a). Synonyms and abbreviations: benzenamine; phenylamine; aminobenzene; aminophen; (b) Aniline hydrochloride aniline oil. NH2 (b) Aniline hydrochloride Chem. Abstr. Serv. Reg. No.: 142-04-1 EC No.: 205-519-8 HCl IUPAC systematic name: aniline hydro - Molecular formula: C6H8ClN chloride Relative molecular mass: 129.59 (NCBI, Synonyms: aniline chloride; anilinium chlo- 2020b). ride; benzenamine hydrochloride; aniline. HCl; phenylamine hydrochloride; phenylam- monium chloride. 1.1.3 Chemical and physical properties of the pure substance Aniline is a basic compound and will undergo acid–base reactions. Aniline and its hydrochlo- ride salt will achieve a pH-dependent acid–base equilibrium in the body. 109 IARC MONOGRAPHS – 127 (a) Aniline Octanol/water partition coefficient (P): log Kow, 0.936, predicted median (US EPA, 2020b) Description: aniline appears as a yellowish Conversion factor: 1 ppm = 5.3 mg/m3 [calcu- to brownish oily liquid with a musty fishy lated from: mg/m3 = (relative molecular odour (NCBI, 2020a), detectable at 1 ppm 3 mass/24.45) × ppm, assuming temperature [3.81 mg/m ] (European Commission, 2016; (25 °C) and pressure (101 kPa)].
  • Toxicological Review of Chloral Hydrate (CAS No. 302-17-0) (PDF)

    Toxicological Review of Chloral Hydrate (CAS No. 302-17-0) (PDF)

    EPA/635/R-00/006 TOXICOLOGICAL REVIEW OF CHLORAL HYDRATE (CAS No. 302-17-0) In Support of Summary Information on the Integrated Risk Information System (IRIS) August 2000 U.S. Environmental Protection Agency Washington, DC DISCLAIMER This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. Note: This document may undergo revisions in the future. The most up-to-date version will be made available electronically via the IRIS Home Page at http://www.epa.gov/iris. ii CONTENTS—TOXICOLOGICAL REVIEW for CHLORAL HYDRATE (CAS No. 302-17-0) FOREWORD .................................................................v AUTHORS, CONTRIBUTORS, AND REVIEWERS ................................ vi 1. INTRODUCTION ..........................................................1 2. CHEMICAL AND PHYSICAL INFORMATION RELEVANT TO ASSESSMENTS ..... 2 3. TOXICOKINETICS RELEVANT TO ASSESSMENTS ............................3 4. HAZARD IDENTIFICATION ................................................6 4.1. STUDIES IN HUMANS - EPIDEMIOLOGY AND CASE REPORTS .................................................6 4.2. PRECHRONIC AND CHRONIC STUDIES AND CANCER BIOASSAYS IN ANIMALS ................................8 4.2.1. Oral ..........................................................8 4.2.2. Inhalation .....................................................12 4.3. REPRODUCTIVE/DEVELOPMENTAL STUDIES ..........................13
  • Are There Single-Well Hydrogen Bonds in Pyridine-Dichloroacetic Acid Complexes? Charles L

    Are There Single-Well Hydrogen Bonds in Pyridine-Dichloroacetic Acid Complexes? Charles L

    Supplementary Material (ESI) for Chemical Communications This journal is © The Royal Society of Chemistry 2009 Are There Single-Well Hydrogen Bonds in Pyridine-Dichloroacetic Acid Complexes? Charles L. Perrin* and Phaneendrasai Karri Electronic Supplementary Information EXPERIMENTAL DETAILS Materials. All pyridines, dichloroacetic acid, and dichloroacetic anhydride were purchased from Aldrich Chemical Company. Pyridines were stored over activated 4Å molecular sieves under dry N2 for several days prior to use. NMR solvents CD2Cl2 and CDCl3 and 1-mL ampoules of H218O (97.6 atom% 18O) were purchased from Cambridge Isotope Labs. Preparation of Cl2CHCOOH-18O2. Dichloroacetyl chloride (0.5 mL, 5 mmol) was stirred in an ice bath with 0.3 mL H218O (16 mmol) for 1 hr, then warmed to 25ºC and stirred. Incorporation of 18O label was monitored by mass spectrometry. After 48 hr the peaks of mono-18O and di-18O2 acids had nearly equal intensites, and the ratio did not change further. The stirring was stopped and water and HCl were evaporated under reduced pressure (<1 mm Hg) for 24 hr. The extent of labeling was confirmed by the 13C NMR spectrum of a 2:1 mixture with unlabeled dichloroacetic acid in CDCl3, which showed three peaks of nearly the same intensity. Preparation of NMR Samples. Samples were prepared under inert atmosphere using syringe transfer techniques. Pyridine or a substituted pyridine (1.2 mmol) was added to dichloromethane- d2 (1 g). Dichloroacetic acid-18O2 (10 uL of 1:1 mixture with dichloroacetic acid-18O, 0.06 mmol each) and dichloroacetic acid (5 uL, 0.06 mmol) were added to the solution.
  • Toxicological Profile for Bromodichloromethane

    Toxicological Profile for Bromodichloromethane

    BROMODICHLOROMETHANE 89 CHAPTER 5. POTENTIAL FOR HUMAN EXPOSURE 5.1 OVERVIEW Bromodichloromethane has been identified in at least 238 of the 1,854 hazardous waste sites that have been proposed for inclusion on the EPA National Priorities List (NPL) (ATSDR 2017). However, the number of sites in which bromodichloromethane has been evaluated is not known. The number of sites in each state is shown in Figure 5-1. Of these sites, 233 are located within the United States, 2 are located in the Virgin Islands, and 3 are located in Puerto Rico (not shown). Figure 5-1. Number of NPL Sites with Bromodichloromethane Contamination • The most likely route of exposure for the general public to bromodichloromethane is through ingestion, inhalation, and dermal contact of chlorinated drinking water. • A median bromodichloromethane intake of 2.8–4.2 µg/day from drinking water has been estimated; inhalation and dermal exposure would add to this daily intake. BROMODICHLOROMETHANE 90 5. POTENTIAL FOR HUMAN EXPOSURE • Bromodichloromethane is formed as a byproduct of water disinfection methods using chlorination. This is the primary source of bromodichloromethane in the environment. • Its principal use is as a chemical intermediate for organic synthesis and as a chemical reagent. • Volatilization is an important fate process. Bromodichloromethane evaporates from sources and enters the environment as a gas, which is slowly broken down in air. Residual bromodichloromethane may be broken down slowly by bacteria. • In the atmosphere, bromodichloromethane is thought to undergo slow degradation through oxidative pathways, with a half-life of about 2–3 months. 5.2 PRODUCTION, IMPORT/EXPORT, USE, AND DISPOSAL 5.2.1 Production The principal anthropogenic source of bromodichloromethane is its unintentional formation as a byproduct during the chlorination of water containing organic materials and bromide.
  • Conversion of Cholesterol to Coprostanol and Cholestanol in the Estuary Sediment

    Conversion of Cholesterol to Coprostanol and Cholestanol in the Estuary Sediment

    Conversion of Cholesterol to Coprostanol and Cholestanol in the Estuary Sediment 著者 "TESHIMA Shin-ichi, KANAZAWA Akio" journal or 鹿児島大学水産学部紀要=Memoirs of Faculty of publication title Fisheries Kagoshima University volume 27 number 1 page range 41-47 別言語のタイトル 海底堆積物におけるコレステロールからコプロスタ ノールおよびコレスタノールへの変換 URL http://hdl.handle.net/10232/13110 Mem. Fac. Fish., Kagoshima Univ. Vol. 27, No. 1, pp. 41-47 (1978) Conversion of Cholesterol to Coprostanol and Cholestanol in the Estuary Sediment Shin-ichi Teshima* and Akio Kanazawa* Abstract This paper deals with the conversion of cholesterol-4-14C to radioactive coprosta nol, cholestanol, and cholestenone in the estuary sediment from Kagoshima Bay, Kagoshima, Japan. The incubation of cholesterol-4-14C with the sediment and sea water gave radio active coprostanol, cholestanol, and cholestenone. The identification of these radio active compounds was performed by thin-layer chromatography and preparative gas- liquid chromatography followed by radioactive measurements. However, the incu bation of cholesterol-4-14C with sterilized sediment and with sea water (or sterilized sea water) produced extremely small amounts of the above mentioned conversion products. These results indicated that the conversion of cholesterol to coprostanol, cholestanol, and cholestenone is effected by the action of microorganisms in the sediment. Several workers have attempted to use coprostanol (5^-cholestane-3y?-ol) as an indicator of fecal pollution in water1"7*. Since the feces of human and mam mals are regarded as the only source of coprostanol in natural environments, the occurrence of coprostanol has been conceived to be indicative of water pol lution in the cause of human life. As to the marine environments, the authors have pointed out the presence of coprostanol in both sea water and the sediments in Ariake Sea, indicating that the concentration of coprostanol was markedly high in the sediments as com pared with that of sea water7).
  • 1,2-DICHLOROETHANE 1. Exposure Data

    1,2-DICHLOROETHANE 1. Exposure Data

    1,2-DICHLOROETHANE Data were last reviewed in IARC (1979) and the compound was classified in IARC Monographs Supplement 7 (1987a). 1. Exposure Data 1.1 Chemical and physical data 1.1.1 Nomenclature Chem. Abstr. Serv. Reg. No.: 107-06-2 Chem. Abstr. Name: 1,2-Dichloroethane IUPAC Systematic Name: 1,2-Dichloroethane Synonym: Ethylene dichloride 1.1.2 Structural and molecular formulae and relative molecular mass Cl CH2 CH2 Cl C2H4Cl2 Relative molecular mass: 98.96 1.1.3 Chemical and physical properties of the pure substance (a) Description: Colourless liquid with a pleasant odour (Budavari, 1996) (b) Boiling-point: 83.5°C (Lide, 1995) (c) Melting-point: –35.5°C (Lide, 1995) (d) Solubility: Slightly soluble in water; miscible with ethanol, chloroform and diethyl ether (Lide, 1995; Budavari, 1996) (e) Vapour pressure: 8 kPa at 20°C (Verschueren, 1996) (f) Flash-point: 18°C, open cup (Budavari, 1996) (g) Conversion factor: mg/m3 = 4.0 × ppm 1.2 Production and use World production capacities in 1988 for 1,2-dichloroethane have been reported as follows (thousand tonnes): North America, 9445; western Europe, 9830; Japan, 3068; and other, 8351 (Snedecor, 1993). Production in the United States has been reported as follows (thousand tonnes): 1983, 5200; 1990, 6300; 1991, 6200; 1992, 6900; 1993, 8100 (United States National Library of Medicine, 1997). The total annual production in Canada in 1990 was estimated to be 922 thousand tonnes; more than 1000 thousand tonnes were produced in the United Kingdom in 1991 (WHO, 1995). –501– 502 IARC MONOGRAPHS VOLUME 71 1,2-Dichloroethane is used primarily in the production of vinyl chloride; 99% of total demand in Canada, 90% in Japan and 88% of total production in the United States are used for this purpose.