Lead Levels in Drinking Water at Salisbury Community

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Costanza Robinson and Davis April 2019 Lead Levels in SCS Drinking Water. Lead Levels in Drinking Water at,Salisbury Community School Salisbury VT. Molly Costanza Robinson Ph D and Gabrielle Davis, Dept of Chemistry Biochemistry Program for Environmental Studies Middlebury College Middlebury. VT Prof of Environ Chemistry mcostanz middlebury edu. April 1 2019,BACKGROUND, Lead exposures derive from a variety of sources including dust from older lead based paint. soil contamination from earlier leaded gasoline and water contamination from leaded pipes solder. and fixtures 1 Dust from leaded paint is believed to be the dominant source of lead exposure but the. EPA estimates that 20 of lead exposure is through drinking water 2 Health effects of lead include. irreversible developmental neurotoxicity 3 disruption of the endocrine and reproductive systems 4. and gastrointestinal and cardiovascular issues 5 Even at low levels 5 g Pb dL blood lead has. been known to decrease IQ scores 3 Because of the health risks posed by lead including that it can. bioaccumulate the U S Environmental Protection agency has set a non enforceable health standard. Maximum Contaminant Level Goal MLCG for lead in drinking water of zero 2 While no level of. lead exposure is considered to be safe for anyone lead exposure is a particular concern in children. Whereas children absorb 50 of Pb that they ingest adults absorb 35 50 6 Furthermore lead s. chemical similarity to calcium promotes uptake into children s bones which can leach out over time. and serve as a long term source of Pb exposure 7 The American Academy of Pediatrics. recommends a maximum lead level in drinking water of 1 g L referred to as ppb or part per. billion 8 Because developing children spend much of their time at school and the effects are. largely irreversible exposure to lead through drinking water in schools is a critical issue 9 10. In 1991 the United States Environmental Protection Agency EPA established the Lead and. Copper Rule which requires public water suppliers to monitor for lead in drinking water and set an. action level for the concentration of lead in drinking water to 15 ppb and a maximum contaminant. level goal of 0 ppb 11 If lead concentrations exceed 15 ppb in more than 10 of customer taps. sampled public water suppliers must take action to control corrosion and inform the public about steps. they should take to protect their health Importantly this action level is used administratively to. evaluate anti corrosion measures and is not a health based standard The American Academy of. Pediatrics has issued a health based recommendation that water fountains in schools not deliver water. exceeding 1 ppb lead 8 Currently schools are not required to test for lead in drinking water unless. they rely on a private water supply and serve more than 25 people daily 12 This results in water. being tested for lead in only 8 11 of schools nationwide 13 Previous national legislative efforts. including those by former Vermont Senator Jim Jeffords to direct the EPA to require states to develop. school testing programs and to address any problems found have been unsuccessful While municipal. water must be tested for lead at the site of distribution and at a small number of end user typically. residential outlets lead can leach into the water at various points within the system including from. lead containing pipes solder and individual outlet fixtures The federal 1986 Safe Drinking Water Act. limited the use of lead pipes and lead containing solders in new drinking water systems where lead. free was defined as less than 0 2 lead for solders and fluxes and not more than 8 lead for pipes. and pipe fittings 14 The amount of lead allowed in lead free products installed after 2010 in. Vermont 15 and after 2014 nationally was reduced 33 fold by redefining lead free as products in. which wetted surfaces of a pipe contain a weighted average of 0 25 lead and the wetted surfaces of. solder and flux contain a weighted average of 0 2 lead The 2011 federal revision also exempted. from lead free requirements certain products that are used exclusively for non potable uses such as. Costanza Robinson and Davis April 2019 Lead Levels in SCS Drinking Water. irrigation outdoor watering or any other uses where the water is not anticipated to be used for human. consumption as well as other products including shower or water distribution main gate valves 2. inches in diameter 14 Because of shifting lead free definitions exemptions from lead free. requirements and uncertainty regarding individual pipe and fixture composition and installation dates. direct testing of water from each outlet is the only way to understand the potential for lead exposure. through drinking water, Data from the U S Center for Disease Control and Prevention CDC in 2016 indicate that. 8 of Vermont children have blood lead levels that exceed Vermont s 5 g dL microgram per. deciliter standard 16 Approximately 150 Vermont schools who are on their own drinking water. supply regularly test some water outlets but few schools have ever had all of their outlets tested In. 2017 the Vermont Department of Health VDH and Agencies of Education and Natural Resources. launched a pilot project to test all drinking water outlets in 16 Vermont public schools that are on. municipal water supplies 17 Results of that pilot showed substantial differences across schools in. the frequency of lead detection and in lead levels 18 Schools ranged from having 0 up to 54 of. outlets exceeding the EPA action level for lead and from 3 88 of outlets exceeding AAP 1 ppb. safety level 1 In response to the VDH pilot and with the support of the Governor the Vermont. legislature took up a bill S 40 An Act Related to Testing and Remediation of Lead in the Drinking. Water of Schools and Childcare Facilities in 2019 to require testing of school drinking water for lead. The Senate unanimously passed S 40 in February 2019 which includes a 3 ppb lead action level the. House is considering the bill In the current draft of the bill the sampling reflected in this report would. be accepted as having fulfilled the requirements of testing but the samples would need to be. reanalyzed by a certified laboratory, Salisbury Community School SCS receives water through its own well and serves more than.
25 people consequently it tests a handful of outlets for lead every three years 19 Under Vermont. state law SCS is also specifically required to tests water for lead in early education preschool. classrooms The current study represents the first time lead levels have been tested in water from all. outlets at SCS,Site Description, Salisbury Community School SCS is located in the town of Salisbury VT and provides pre. kindergarten through 6th grade instruction 20 SCS is part of the Addison Central School District. which oversees public schools in the area SCS was constructed in 1997 with minor renovations since. then Any replacement of fixtures and other water infrastructure was performed in compliance with the. lead free requirements of the 1986 Safe Drinking Water Act We worked with ACSD Facilities. Manager Eric Warren on the study design including completion of a plumbing questionnaire and. mapping of flow paths 2 All water outlets in the school n 35 were mapped by location and type. Outlets sampled at SCS included a source sample sinks conventional and floor utility water. fountains bottle fillers kitchen sprayers and a shower Figure 1 Mapping included noting the flow. path of water from the initial water entry point to the school Knowledge of the water flow path is. critical to the integrity of water sampling as outlets need to be sampled in sequence from upstream to. The AAP health based recommendation is made specifically for water fountains but would reasonably be applied to any. outlet used for direct consumption by children Information regarding use of outlets for consumption was not publicly. available for statewide pilot, EPA Plumbing Profile Questionnaire can be found on p 96 of EPA 2006 and includes questions regarding pipe and. fixture type and composition building age and dates of renovation among other information. Costanza Robinson and Davis April 2019 Lead Levels in SCS Drinking Water. downstream to avoid inadvertent flushing of pipes and fixtures prior to sampling We did not. independently verify information provided to us regarding plumbing and water flow in the school. Figure 1 Salisbury Community School floor plan showing water flow paths arrows and water outlet sample. locations with colors representing main branch lines The location of water input to the school is in the. marked with a star Marker shapes indicate fixture type The sample naming scheme associated with outlets is. provided in Appendix A The floor plan with outlet locations labeled by Outlet ID is provided in Appendix B. Sample Collection, Water was sampled on a Saturday morning January 12 2019 during the regular school year. and prior to any use for the day 3 Water should ideally sit stagnant in the pipes and fixtures for least 8. h but no more than 12 h before collection 4 Water samples were collected in certified clean HDPE. Nalgene bottles 250 mL 5 Two types of samples were collected first draw FD and flush samples. FL Table 1 The two types of samples collectively provide information on the source of lead in the. water and therefore on appropriate remediation measures First draw FD samples were obtained by. collecting the first 250 mL of water from each outlet After all FD samples were collected FL samples. were obtained by flushing water out of the outlets for 30 seconds and then collecting another 250 mL. Two field blanks were collected at Middlebury College the day before sample collection using ultra. purified water and were exposed to the sampling conditions of SCS The sample naming scheme and. The U S EPA 2006 recommends against sampling during holidays or periods of time that the school is not in regular use. in order to avoid collecting samples that have non representative high levels of lead. Some outlets are used infrequently and had likely been sitting for longer than 8 12 h We considered this to be in. keeping with the goals of the EPA guidance in that our samples are representative of what a student might encounter at. that particular outlet on a given day, School samples are smaller than the 1 L sample collected by public water suppliers for compliance with the Lead and. Copper Rule A smaller sample is more effective at identifying the sources of lead at an outlet because lead sample is also. more representative of water per serving consumed by a child EPA 2006. Costanza Robinson and Davis April 2019 Lead Levels in SCS Drinking Water. SCS floor plan showing outlet locations labeled by outlet ID are provided in Appendix A and B. respectively, Table 1 Types descriptions and rationale for samples collected.
Sample Type Description and Rationale, First Draw First 250 mL of water to exit outlet after sitting stagnant in pipes for 8 12 hours see footnote 2. FD on p 3 Provides information on Pb in the drinking water from all sources including water. coming in to the school water pipes and the outlet fixtures and connections. Flush FL First 250 mL of water to exit outlet after sitting stagnant in pipes for 8 12 having taken a FD. sample and subsequently having been flushed for 30 seconds Provides information on Pb in. the drinking from all sources excluding the outlet fixtures and immediate connections i e. from more distant connections pipes and or incoming water. Sample Preparation and Lead Analysis, After collection samples were placed in a cooler and within 48 hours were acidified to 0 5. 1 25 mL trace metal grade HNO3 for preservation After 16 h or more sample turbidity was verified. to be 1 NTU and acidity pH 2 Two samples had high turbidity and their reported lead level are. considered low estimates of actual total lead 6 Samples were analyzed for lead using inductively. coupled plasma mass spectrometry manufacturer recommended conditions and conventional quality. control and quality assurance methods 7 Lead concentrations are reported to the nearest part per billion. ppb i e g Pb L water for samples at above the limit of quantification LOQ 0 5 ppb as 0 5 ppb. for samples with detectable lead below the LOQ and as non detect n d for samples with lead levels. below the limit of detection 0 1 ppb, A health based prioritization of outlet remediation highest high or moderate priority is made. based on the measured lead levels in FD samples and the potential use of the outlet for consumption or. cooking Lead levels are evaluated relative to three standards the administrative not health based. EPA action level for lead of 15 ppb the American Academy of Pediatrics health based safety standard. for school water fountains of 1 ppb and the anticipated Vermont state action level for drinking water. in schools of 3 ppb,RESULTS DISCUSSION,Lead Level Summary. Water from 35 outlets was sampled including collecting one FD and one FL sample from each. outlet FD samples are used to evaluate lead exposures while FL samples are used to evaluate the. potential source of any lead found Complete sample data are provided in Appendix C Summary. results for FD samples are shown in Figure 2 All outlets produced FD samples with detectable lead. but in roughly half the cases the lead was at 1 ppb or lower and therefore meets the AAP. Lead Levels in Drinking Water at Salisbury Community School Salisbury VT Molly Costanza Robinson Ph D and Gabrielle Davis Dept of Chemistry amp Biochemistry Program for Environmental Studies Middlebury College Middlebury

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