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Toronto ’ s Management of Lead Service Lines Lead Colloborative Consortium Workshop, June 8, 2012 Howard Shapiro, Toronto Public Health. 1. What is a Service Line / Water Service?. Health effects seen at levels of lead in current population Lead exposure should be minimized where possible
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Toronto’s Management of Lead Service Lines Lead Colloborative Consortium Workshop, June 8, 2012 Howard Shapiro, Toronto Public Health 1
Health effects seen at levels of lead in current population • Lead exposure should be minimized where possible • However, issue portrayed as individual crisis • Question for TPH was is significance of water lead levels that are slightly above drinking water guidelines • Communication to public • Management strategies Overall Approach and Issues
Toronto • City 2.7 million • Very active media presence • History of lead contamination in certain communities now largely resolved • Lead not much of an issue in recent past • Spring 2007 lead found in London, Ontario drinking water above drinking water standard in older homes due to lead services • Toronto media asks about situation in Toronto Situation
Samples from 5 Minute Flush How Big a Problem?
Desire to not counter extensive promotion of Toronto’s water • Water leaving treatment plant very low in lead • Water from Toronto homes within Ontario Drinking Water Standard for lead • Homes built before 1955 usually have lead service and may have high lead in water • Can find out by requesting free water test from Toronto Water • While waiting use water filter Early Messaging
Tried to provide health context • Effects of lead at this level in water would be subtle on intelligence of children but not detectable but parent or physician • Water one source of lead but not only one • Important in older homes with lead pipes since likely to have lead paint, lead in soil • Takes place within trends of decreasing lead levels over time • Developed TPH web pages for lead • Very hard to distinguish between population and individual importance of lead Early Messaging
Of City side only • Homeowner can pay to have their side done at same time • When: • At time of scheduled water main replacement • During emergency repairs • In response to high lead water test • On request (long waiting period) • Toronto Water reluctant to undertake corrosion control Early Program Focused on Replacement
Estimated 65,000 lead services • 28,000 already replaced • Original plan 13 year time frame • Accelerate replacement to 9 years • Additional $19 million per year • Mainly through increasing main replacement in area likely to have lead services Toronto Water Accelerates Program
Requires twice yearly testing • 2 X 1 litre samples • 30 minutes stagnation after flushing • 100 homes in large city such as Toronto • Benchmark – 10 ppb 90 %ile • Corrosion Control plan if fail 2 out of 3 consecutive rounds of testing Province Introduces New Rules
Trained nurses doing neonatal visits in lead water issue • Initiated development of filter faucet rebate program • Sent postcard to approx. 50,000 homes in areas likely to have LSL Changes to Approach
Testing of water for lead not a good way to risk stratify individual homes • Intermittent particulate release • Impact of water on lead levels may be more significant than some studies suggested • Replacing part of lead service with copper may be worse than leaving entire lead line Existing and Developing Information
Edwards et al. Environ. Sci. Technol. 2009 • Showed impacts of spike in DC water levels on BLL’s • Incidence of BLL > 10 μg/dL increased 4 times for children ≤1.3 years during time of high lead water levels • CDC Issues notice in 2010 about past MMWR • Cross-sectional study of people with high water lead levels (> 300 ppb) in DC flawed • Sampling time of blood and water not known • Issue was a temporary spike in water lead levels in DC • Also warned against partial replacement Further Developments Water Impact
Galvanic Corrosion can Increase Lead Levels • Process used in batteries • Occurs with metals of different electrical potential • Results in corrosion of one metal • With lead and copper results in corrosion of lead • Lead levels can be higher than lead pipe alone
Accelerated LSL replacement discontinued • Now only done as part of state of good repair (e.g. when replacing main) • Water filter and information sheet left at each home after all LSL replacements • Corrosion control is being implemented Additional Changes
Water testing de-emphasized for individual homes • Not promoted for individuals to risk stratify • People can request LSL replacement without water testing so long as commit to replacing their side • Vulnerable groups are encouraged to use filter until lead service removed (no longer based on testing result) • Re-evaluating communication strategy based on survey of homes with partial and full LSL replacements Additional Changes
Howard Shapiro • Toronto Public Health • hshapir@toronto.ca • 416-338-8562 Questions