Www.benkeet.com ©2014 Ben Keet 1 Development of the ‘Ben Keet Method’ of house dust analysis to identify lead and other contaminants Drs. Ben Keet, SQEP,

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www.benkeet.com 2014 Ben Keet 1 Development of the Ben Keet Method of house dust analysis to identify lead and other contaminants Drs. Ben Keet, SQEP, FRSC, MRSNZ, MinstD Geo & Hydro K8 Ltd e-mail: ben@benkeet.comben@benkeet.com Slide 2 After years of cleaning up industrial sites . I realised need to focus on the important issues Like the environmental effects on people, esp. Children This requires a change from commercial environmental engineering to social environmental engineering www.benkeet.com2011 Ben Keet 2 Slide 3 However CHANGE, - happens even when you dont expect it - but not always the way you want - or as fast www.benkeet.com2011 Ben Keet 3 Slide 4 www.benkeet.com2011 Ben Keet 4 Estimated costs of paediatric lead poisoning, United States, 1997. Environment Attributable Factor (EAF)= 100% Main consequence = Loss of IQ over lifetime Mean blood lead level in 1997 among 5-year-old children= 2.7 g/dL A blood lead level of 1 g/dL I points per child= Mean loss of 0.25 Therefore, 2.7 g/dL = Mean loss of 0.675 IQ points per child Loss of 1 IQ point = Loss of lifetime earnings of 2.39% Therefore, loss of 0.675 IQ points = Loss of 1.61% of lifetime earnings Economic consequences For boys: loss of 1.61% $881,027 (lifetime earnings) 1,960,200 = $27.8 billion For girls: loss of 1.61% $519,631 (lifetime earnings) 1,869,800 = $15.6 billion Total costs of paediatric lead poisoning = $43.4 billion Environmental Pollutants and Disease in American Children: Estimates of Morbidity, Mortality, and Costs for Lead Poisoning, Asthma, Cancer, and Developmental Disabilities, Philip J. Landrigan, Clyde B. Schechter, Jeffrey M. Lipton, Marianne C. Fahsand Joel Schwartz, The Center for Childrens Health and the Environment, The Department of Community and Preventive Medicine, and The Department of Pediatrics, Mount Sinai School of Medicine, New York, New York, USA; Environmental Health Perspectives VOLUME 110 | NUMBER 7 | July 2002 For me it started with realizing the social costs of lead poisoning. Searching I only found financial implications : Whaw ! Slide 5 www.benkeet.com2014 Ben Keet 5 Environmental attributable cost by condition Base-case (US $ Billion) Lead poisoning50.9 Methyl Mercury tox5.1 Asthma2.2 Intellectual Disability5.4 Autism7.9 ADHD5 Ref. Leonardo Trasande and Yinghua Liu Reducing The Staggering Costs Of Environmental Disease In Children, Estimated At $76.6 Billion In 2008 (published online May 4, 2011; 10.1377/hlthaff.2010.1239), 30, no.5 (2011):863-870 Health Affairs Lead = 66% of total cost of $ 76.6 Billion just in USA 6 years and a few $m R&D later same outcomes Slide 6 Hypothesis: In NZ the cost per person is 2 x higher NZ$ 1.5 Billion (annually ! ) reasons: NZ houses: Many of wood and w/b all walls painted v.s. US houses: Many of brick only windows and doors painted Interiors NZ: - mainly painted v.s. US:- high use of wall paper NZ phased out last lead-based paint around 1982 v.s. US phased out lead-based paint around 1965 NZ average disposable income is much lower than in the US leading to poor maintenance and less re-painting. www.benkeet.com2008 Ben Keet 6 Slide 7 Lead-based paint history www.benkeet.com2011 Ben Keet 7 Pre-1945 - 70 paint > 50% Pb Start phase out world-wide in late 60-ies Still in use in NZ in mid 80-ies Slide 8 1980 - 1.000.000 households in NZ 1984 BRANZ estimates: 251.000 properties with lead based paint www.benkeet.com2011 Ben Keet 8 Ref. NZ Statistics Slide 9 Difference US - NZ NZ US (RRP = Renovation Repair Painters) On January 1, 2011, firms working in pre-1978 homes and child- occupied facilities must be certified and use lead-safe work practices during renovations. The penalty for noncompliance is $37,000 per day, per violation and possible jail time www.benkeet.com2014 Ben Keet 9 Dominion Post 27 July 2011 Are we taking Lead serious in NZ? Slide 10 How my journey began 2006 (I just got a handheld XRF analyser) Parent from school requests assessment of house and garden as his 2 yr old became sick a few weeks after moving in a new (old) house (30-ies) Lead level in garden around house was > 2000 mg/kg Swipe test of floors gave > 20 mg/m 2 of lead (US clearance = 100 g/ft 2 ) [20 x over] Swipes: cumbersome, variable and costly. very dependent on time since cleaning (info from mother re last cleaning = invariably wrong) www.benkeet.com2014 Ben Keet 10 Slide 11 Late 2006 More house surveys Used battery vacuum cleaner to take dust samples Main flaw: Areas most frequented and also most often cleaned Surveys biased towards least used and least cleaned areas. www.benkeet.com2014 Ben Keet 11 Slide 12 2007 Used vacuum cleaner bag to get average dust sample Useful as the most used areas are also most often vacuumed Started to separate the dust into grain size fractions www.benkeet.com2011 Ben Keet 12 Very first sieved house dust analysis Slide 13 If on site: analyse painted surfaces & soil www.benkeet.com2011 Ben Keet 13 And mark with lead concentration Soil Slide 14 2008: FREE survey at HB Field Days www.benkeet.com2014 Ben Keet 14 Stand in HBRC marquee Opposite entrance gate 6000 visitors 3 days 14 people signed up 4 gave permission to publish results Slide 15 Main stumbling blocks Home owners dont want bad info on their property (value worries) Many prefer not to know (ostriches) If it was an issue, the council would inform us Solution: Vacuum cleaner bags dropped off at intermediary (Environment Centres) Or send direct to independent lab: Now the Ben Keet Method is offered by Hill Laboratories www.benkeet.com2014 Ben Keet 15 Slide 16 Some results www.benkeet.com2011 Ben Keet 16 Every analysis tells a story There are similarities Slide 17 Initial findings: Analysis of fine and coarse fractions gives total concentration AND an indication where the problem may be: Coarse particles containing lead originate mainly from indoors Fine particles containing lead may be carried in house from outdoors My hypotheses: 1 Better correlation blood lead level - lead in fine dust (i.e. soil is important) 2 Lead concentration in particle seize indicates source 3 Mass identification of houses with high lead is possible using a Aerial photographs b Visual indicators Possible other factors; lead speciation, bio-availability www.benkeet.com2014 Ben Keet 17 Slide 18 Conclusion:Ben Keet Method of house dust analysis is Potentially Better Significantly Cheaper Using dust from vacuum cleaner bag provides: House average lead concentration in dust for most used areas Rapid assessment of potential lead exposure Significant savings compared to wipe tests Can be carried out off-site even anonymous www.benkeet.com2008 Ben Keet 18 Recommended remediation of lead-paint surfaces: Clean surfaces with ammonia / sugar soap solution Re-paint with acrylic based paint Recommended for garden soil high in lead: Ensure good mats at house entrance Replace soil or cover with new soil + indicator layer Slide 19 Further work, recommendations and R&D needed www.benkeet.com2011 Ben Keet 19 Study relationship lead in dust fractions with blood lead level (bll) Lead dust surveys should be carried out in all pre 1980 houses with small children Lead dust house surveys should be recommended by Plunket for all pregnant woman Testing for lead in blood of pregnant woman and babies should become standard in NZ ( as in is in the US and many EU countries ) MfE, DHBs, councils should subsidise remedial work (re-painting / soil work) of older houses, especially for households with young kids (just like house insulation) Slide 20 Housing Authority of Baltimore City is to pay nearly $12 million in court-ordered judgments that it owes former public housing tenants who suffered lead-paint poisoning years ago as children. By Scott Calvert, The Baltimore Sun8:59 a.m. EDT, August 18, 2011 http://www.baltimoresun.com/health/bs-md-brochin-lead-paint-20110817,0,7720622.story?goback=%2Egde_164261_member_68234249 www.benkeet.com2014 Ben Keet 20 Thank you for your attention Questions discussion.. Reminder: