Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment Subgroup Report on the Lowermoor Water Pollution Incident 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 1 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 2 Chapter 1: Executive Summary 13 Chapter 2: Introduction 21 Historical perspective 21 Terms of reference of COT Subgroup 23 Membership of Subgroup 23 Methods of working 23 Dates of meetings and visits 25 Chapter 3: The Lowermoor water pollution incident: water supply and contamination 27 Introduction 27 Lowermoor Water Treatment Works 27 The pollution incident 32 The distribution of contaminated water 33 The nature of the contamination of the water supply 33 Calculated values for the aluminium sulphate concentration in the Lowermoor Water Treatment Works 34 Collection of water samples for water quality analysis 35 Water quality data from SWWA and South West Water Ltd 36 Introduction 36 Pre-incident monitoring data 38 Results of monitoring – 7 July to 4 August 1988 41 Results of monitoring – 5 August to 31 December 1988 57 Results of monitoring – 1989 61 Monitoring data from other sources 63 Modelling of pollutant concentrations in Lowermoor treatment works and in trunk main system 64 Indications of copper concentrations in the contaminated water 72 Other water pollution incidents involving aluminium sulphate 73 Key points 73 Chapter 4: The assessment of exposure to contaminants 77 Introduction 77 Calculated estimates of exposure by the oral route 77 Water consumption data 77 Possible intakes from food 78 Water quality data 78 Estimated exposure to contaminants from 7 July to 4 August 1988 79 Estimated exposure to contaminants from 5 August 1988 to 31 December 1989 85 Modelling of exposure estimates 88 Modelling by Black and Veatch Consulting Ltd 88 Modelling by Crowther Clayton Associates Ltd 88 Dermal exposures 91 Key Points 91 Chapter 5: Evidence from individuals and population studies from the North Cornwall area 95 Introduction 95 Personal evidence 95 Population studies 95 Data from personal testimonies made by members of the public 96 Contents 3 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 3 Introduction and method of working 96 General observations 97 Water quality, usage and consumption 97 Reported health effects (Adults) 99 Reported health data (Children) 101 Information provided by health professionals 101 Dr David Miles 101 General practitioners: Dr Chris Jarvis, Dr James Lunny, Dr Anthony Nash and Dr Richard Newman 105 Dr Ian Coutts 107 Mrs Jenny McArdle 108 Studies of the North Cornwall population 108 Epidemiological studies 108 Neuropsychological testing 115 Questionnaire survey 124 Homeopathic data 124 Data on Educational Assessment 125 Children with special educational needs 125 Tissue analyses 128 Taylor (1990) 128 Eastwood et al (1990) 128 McMillan et al (1993) 129 Powell et al (1995) 129 Howard (1993) 130 Ward (1989) 131 Critical appraisal of studies on tissue analysis 131 Effects on livestock and domestic animals 132 Types of Effects Reported 132 Concentrations of Contaminants in Animal Tissues 132 The concentration of aluminium in ice cream 133 Fish 133 Discussions with Mr Cooper 133 Report by Dr W. M. Allen 134 The Veterinary Investigation Centre 134 Appraisal of the effects on livestock and domestic animals 134 Key Points 135 Chapter 6: Toxicological and epidemiological data on contaminants from the scientific literature 139 Introduction 139 Aluminium 140 Introduction 140 General information 140 The chemistry, absorption and bioavailability of aluminium 141 The distribution of aluminium in the body 144 The excretion of aluminium 144 The toxicity of aluminium – acute and short-term effects 146 The neurotoxicity of aluminium 147 Effects on bone 150 Aluminium and carcinogenesis 150 Reproductive and developmental toxicity 151 4 COT Lowermoor Subgroup 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 4 Other effects 152 Recommended upper level intakes 152 Copper 153 Introduction 153 General information 153 The absorption, distribution and excretion of copper in man 154 The toxicity of copper 154 Recommended upper level intakes 156 Zinc 156 Introduction 156 General information 156 The absorption, distribution and excretion of zinc in humans 156 The toxicity of zinc 157 Recommended upper level intakes 157 Lead 158 Introduction 158 General information 158 The absorption, distribution and excretion of lead in humans 158 The toxicity of lead 159 Recommended upper level intakes 160 Manganese 160 Introduction 160 General information 160 The absorption, distribution and excretion of manganese in humans 161 The toxicity of manganese 161 Recommended upper level intakes 162 Iron 163 Introduction 163 General information 163 The absorption, distribution and excretion of iron in humans 164 The toxicity of iron 164 Recommended upper level intakes 165 Metal-metal interactions 165 Introduction 165 Interactions with aluminium 166 Interactions with lead 167 Interactions between the essential metals 167 Sulphate 167 Acidity (pH) 168 Key points 168 Chapter 7: Implications for health of exposure to the contaminants 173 Introduction 173 WHO Guideline Values 173 Overview of contaminant concentrations 174 Aluminium, copper and lead 174 Sulphate, zinc, manganese and iron 174 Methods used to estimate exposures 175 5 Consultation Report January 2005 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 5 Aluminium 177 Exposures 177 Toxicity 180 Discussion 181 Copper 183 Exposures 183 Toxicity 184 Discussion 185 Zinc 185 Exposures 185 Toxicity 186 Discussion 186 Lead 187 Exposures 187 Toxicity 188 Discussion 189 Manganese 190 Exposures 190 Toxicity 191 Discussion 191 Iron 192 Exposures 192 Toxicity 193 Discussion 193 Sulphate 194 Acidity (pH) 194 Additive/synergistic effects of contaminants 195 Key Points 196 Chapter 8: Evaluation of the health effects reported following the Lowermoor incident 199 Introduction 199 The exposure of individuals to contaminants 200 Symptoms experienced at the time, or months or years after the event 201 Health outcomes in the population and scientific data 202 Health effects 202 Acute effects 203 Chronic effects 203 Sensitivity to tapwater 207 Behaviour and academic performance of children 207 Chapter 9: Recommendations 209 Future monitoring and research on health 209 Future handling of similar incidents 210 References 213 Abbreviations 229 Glossary of Terms 231 6 COT Lowermoor Subgroup 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 6 Appendices Appendix 1: Membership of the Lowermoor Subgroup 243 Appendix 2: Membership of the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment 245 Appendix 3: Health and other professionals who provided information 247 Appendix 4: Discussion of the quality and reliability of scientific data 249 Appendix 5: Drinking water quality – the legislative framework 255 Appendix 6*: Water quality data for the parishes of Camelford, Davidstow, Advent, St Minver Lowlands 259 and St Minver Highlands Appendix 7*: Water quality data for the parishes of Camelford and Davidstow, 1989 259 Appendix 8*: Water quality data for the parishes of St Teath, Tintagel and Trevalga 259 Appendix 9*: Water quality data for the parishes of St Endellion, Forrabury & Minster and St Juliot 259 Appendix 10: Lowermoor water quality modelling report. Black and Veatch Consulting Ltd. August 2004 261 Appendix 11: Other water pollution incidents involving aluminium sulphate 297 Appendix 12: Report on the estimated consumption of aluminium, sulphate, copper, zinc, lead and pH following the 299 contamination incident on 6th July 1988. Crowther Clayton Associates. Report no. 91/2737 Appendix 13: Extract from “The Health of the Population”, Department of Public Health Medicine, Cornwall and 301 Isles of Scilly Health Authority, 1988 Appendix 14: Letter from DHSS to Dr CR Grainger, 24 August 1988 309 Appendix 15: Summary and critique of epidemiological studies of the North Cornwall population 317 Appendix 16: Review paper on aluminium prepared for the Lowermoor Subgroup by the 331 Department of Health Toxicology Unit, Imperial College Appendix 17: Review paper on metal-metal interactions prepared for the Lowermoor Subgroup by the 402 Department of Health Toxicology Unit, Imperial College Appendix 18: Current procedures for the management of chemical incidents 445 Appendix 19: Declaration of Lowermoor Subgroup members’ interests 447 7 Consultation Report January 2005 * On CD only. 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 7 Table 1: Theoretical concentrations of aluminium and aluminium sulphate in the treated water reservoir, 35 if mixing had been complete Table 2: Standards and guidelines for drinking water quality 39 Table 3: Water quality data from SWWA for the North Cornwall area, 6 January 1988 to 5 July 1988 – a summary 40 Table 4: Water quality data from SWWA for the Lowermoor water distribution area, 7 July 1988 to 4 August 1988 42 Table 5: Aluminium concentrations in samples taken from two locations at intervals from 9 July 1988 to 2 August 1988 52 Table 6: Number of sample results from SWWA monitoring data provided for each contaminant, 57 5 August to 31 December 1988 Table 7: Percentage of sample results between 5 August and 31 December 1988 containing more than 0.2 mg aluminium/l 58 Table 8: Number of results exceeding 1984 WHO Guideline Value, 5 August 1988 to 31 December 1988 58 Table 9: Locations and dates of samples containing high concentrations of contaminants between 5 August 61 and 31 December 1988 Table 10: Number of sample results from SWWA monitoring data provided for each contaminant in 1989 62 Table 11: Number of results exceeding 1984 WHO Guideline Value in 1989 62 Table 12: Locations and dates of samples where at least one parameter had high concentrations of contaminants in 1989 63 Table 13: Water quality data obtained from other sources 64 Table 14: Maximum modelled aluminium concentration (mg/l) for specific locations (from Black and Veatch 72 Consulting Ltd, 2004) Table 15: Estimated worst-case exposures to aluminium (calculated using water quality data from SWWA) 80 Table 16: Estimated exposures to aluminium (calculated using water quality data from non-SWWA samples) 80 Table 17: Estimated worst-case exposures to copper (calculated using water quality data from SWWA) 82 Table 18: Estimated exposures to copper (calculated using water quality data from non-SWWA sources) 83 Table 19: Estimated exposures to zinc from the 3 samples containing concentrations in excess of the 1984 WHO Guideline Value (calculated using water quality data from SWWA and other sources) 83 Table 20: Estimated worst-case exposures to lead (calculated using water quality data from SWWA) 84 Table 21: Estimated exposures to lead (calculated using water quality data from other sources) 84 Table 22: Estimated exposures to aluminium from the 3 samples containing the highest concentrations in excess of the 1984 WHO Guideline Value (calculated using water quality data from SWWA) 85 Table 23: Estimated exposures to copper from the 3 samples containing the highest concentrations in excess of the 1984 WHO Guideline Value (calculated using water quality data from SWWA) 86 Table 24: Estimated exposures to zinc from the 3 samples containing water in excess of the 1984 WHO Guideline 86 Value (calculated using water quality data from SWWA) Table 25: Estimated exposures to lead from the 3 samples containing the highest concentrations in excess of the 87 1984 WHO Guideline Value (calculated using water quality data from SWWA) Table 26: Estimated exposures to manganese from the 3 samples containing the highest concentrations in 87 excess of the 1984 WHO Guideline Value (calculated using water quality data from SWWA) Table 27: Estimated exposures to iron from the 3 samples containing the highest concentrations in excess of the 1984 87 WHO Guideline Value (calculated using water quality data from SWWA) Table 28: Estimated worst-case exposures to aluminium (calculated using results of modelling by Black and 88 Veatch Consulting Ltd) Table 29: Commonly-reported conditions attributed to the incident by 54 individuals 100 8 COT Lowermoor Subgroup 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 8 Table 30: Less commonly-reported conditions attributed to the incident 101 Table 31: Standardised mortality ratio (95% confidence intervals), July 1988 to December 1997 (from Owen et al, 2002) 111 Table 32: Cancer incidence, July 1988 to December 1998 (from Owen et al, unpublished report) 112 Table 33: Cancer mortality, July 1988 to December 1988 (from Owen et al, unpublished report) 112 Table 34: Leukaemia incidence, July 1988 to December 1998 (from Owen et al, unpublished report) 114 Table 35: Leukaemia mortality, July 1988 to December 1998 (from Owen et al, unpublished report) 114 Table 36: Battery of tests administered by McMillan et al (1990, 1993) 116 Table 37: Details of subjects examined by McMillan et al (1993) 117 Table 38: Tests carried out by Altmann et al, 1999 120 Table 39: Average Richmond test scores and year of administration 123 Table 40: Percentages of children with statements (SEN Stage 5), 1997 to 2001 127 Table 41: A summary of changes in metal concentrations in pig tissue from exposed animals compared to tissues 133 from non-exposed animals Table 42: The most sensitive neurological responses observed following aluminium exposure in animals 151 Table 43: 1984 WHO Guideline Values (GV) for drinking water quality and current standards 173 Table 44: Percentage of SWWA samples (total number of samples) exceeding the relevant 1984 WHO Guideline 174 Values for aluminium, copper and lead in drinking water Table 45: Percentage of SWWA samples (total number of samples) exceeding 1984 WHO Guideline Values for 175 manganese and iron in drinking water Table 46: Estimated worst-case exposures to aluminium from drinking water, 7 July to 4 August 1988 177 (calculated and modelled using water quality data from SWWA) Table 47: Estimated exposures to aluminium from drinking water, 6 to 11 July 1988 (calculated using 179 concentrations of aluminium in water samples from non-SWWA sources)z Table 48: Estimated worst-case exposures to aluminium from drinking water, 6 July to 4 August 1988 179 (calculated using the results of modelling by Black and Veatch Consulting Ltd, Appendix 10) Table 49: Estimated exposures to aluminium from drinking water, calculated from the 3 highest concentrations 180 recorded between 5 August 1988 and 31 December 1988 (SWWA data) Table 50: Usual intakes of aluminium from food and water and potential intakes from medicines (mg/kg bw/day) 181 Table 51: Summary of margin of safety (MoS) for aluminium after the pollution incident 182 Table 52: Estimated worst-case exposures to copper from drinking water, 8 July 1988 to 4 August 1988 184 (calculated using water quality data from SWWA) Table 53: Estimated exposures to copper from drinking water (calculated using water quality data from 184 non-SWWA sources) Table 54: Usual intakes of copper from food and water and potential intakes from medicines and dietary 185 supplements (mg/kg bw/day) Table 55: Estimated exposures to zinc from drinking water calculated forsamples taken between 186 6 July 1988 and 4 August 1988 which exceeded the 1984 WHO Guideline Value Table 56: Usual intakes of zinc from food and water and potential intakes from dietary supplements (mg/kg bw/day) 187 9 Consultation Report January 2005 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 9 Table 57: Estimated worst-case exposures to lead from drinking water, 8 July 1988 to 4 August 1988 (calculated 188 using water quality data from SWWA) Table 58: Estimated exposures to lead from drinking water (calculated using water quality data from non-SWWA sources) 188 Table 59: Usual intakes of lead from food, water, air and dust (mg/kg bw/day) 189 Table 60: Estimated worst-case exposure to manganese from drinking water, 6 July to 4 August 1988 190 (calculated from SWWA data) Table 61: Usual intakes of manganese from food and water and potential intakes from dietary supplements 191 (mg/kg bw/day) Table 62: Worst-case estimated exposures to iron from drinking water, 6 July to 4 August 1988 193 (calculated from SWWA data) Table 63: Usual intakes of iron from food and water and potential intakes from dietary supplements 193 (mg/kg bw/day) 10 COT Lowermoor Subgroup 78933-COI-Toxic-Lowermoor ch1-4 21/1/05 10:58 pm Page 10 [...]... at increased concentrations in the water at the tap The chapter describes the structure of the works, the distribution of contaminated water, the nature of the contamination of the water supply, water quality data on the concentrations of the contaminants from 13 78933-COI-Toxic -Lowermoor ch 1-4 21/1/05 10:58 pm Page 14 COT Lowermoor Subgroup before the incident to the end of 1990, and modelling of the. .. groups, confidentiality was observed 25 78933-COI-Toxic -Lowermoor ch 1-4 21/1/05 10:58 pm Page 26 78933-COI-Toxic -Lowermoor ch 1-4 21/1/05 10:58 pm Page 27 3 The Lowermoor water pollution incident: water supply and contamination Introduction 3.1 This chapter gives an overview of the Lowermoor water pollution incident, describes the distribution of contaminated water and summarises the monitoring data... committee, the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT), to advise on whether the pollution incident had resulted in delayed or persistent health effects, and on the need for additional monitoring and research (Department of Environment, Food and Rural Affairs, 2001) The COT set up a Subgroup, the Lowermoor Subgroup (LSG), under the Chairmanship of Professor... data on the neurotoxicity of aluminium and of its potential role in neurological disease and other disorders such as macrophagic myofasciitis • further investigations of the bioavailability of aluminium in humans, including of the reasons for the reported interindividual variation C Future handling of similar incidents 1.38 There have been considerable improvements in contingency arrangements for and the. .. This report of the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) considers the human health effects of the chemical exposure resulting from the water pollution incident which occurred in July 1988 at the Lowermoor Water Treatment Works, North Cornwall The report was drafted by a specially convened Subgroup of the Committee which was asked to address the following... time of the incident We also consulted evaluations of the relevant toxicology and epidemiology made by authoritative groups such as the World Health Organization (WHO) and the Expert Group on Vitamins and Minerals (EVM) • The commissioning of studies from outside contractors to increase our understanding of the water contamination incident and the passage of contaminants in the water distribution system... studies In Chapter 9, recommendations are made both for future monitoring and research on health and for the future handling of similar incidents Conclusions Who received contaminated water and how long was the water supply contaminated after the pollution incident? 14 78933-COI-Toxic -Lowermoor ch 1-4 21/1/05 10:58 pm Page 15 Consultation Report January 2005 1.10 With the exception of those locations for... transient individuals e.g holiday makers who are in the area temporarily at the time of the incident, consideration must be given as to how to identify this population for inclusion in any future monitoring programme • consideration of the effect of contamination upon the intake of chemical species from food when there are either direct or indirect routes for the contamination of food 19 78933-COI-Toxic -Lowermoor. .. after the contamination incident and very few water samples exceeded the 1984 WHO Guideline Value for zinc 1.12 Water quality data on the contaminants arising from the flushing exercises indicated that the proportion of samples with concentrations of manganese above the relevant 1984 WHO Guideline Value increased in the month after the incident but fell markedly thereafter The proportion of iron samples... to infectious agents However, the study found that the pollution incident did not cause an increased incidence of infection 1.30 There was no indication from the toxicological data on the contaminants of an adverse effect on the thyroid gland Thyroid disease is common in the population and the cases reported are considered unlikely to be caused by exposure to the contaminants resulting from the incident . Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment Subgroup Report on the Lowermoor Water Pollution Incident 78933-COI-Toxic -Lowermoor. chapter describes the structure of the works, the distribution of contaminated water, the nature of the contamination of the water supply, water quality data on the concentrations