Update 9/2/16: NY Times reports that NYC will change their method of lead testing in school water but unclear if this methodology would match best practices: "In the future the city would try to conduct as many tests as possible while school was in session, and on mornings other than Mondays, and that for these tests it would abandon the pre-stagnation flushing step. But she said the city would continue doing the pre-stagnation flushing when it was necessary to collect samples on Monday mornings or over school holidays." More here.
Update 9/1/16: WNYC/Schoolbook reported today that the city said it will stick to its discredited method of testing for lead in school water, even though it doesn't follow EPA protocols and the foremost expert on lead contamination said their results were essentially meaningless. The reporter, Beth Fertig, also linked to this blog for the discussion below of how even very low levels of lead in blood have been linked to lower test scores and higher rates of special needs. For the full list of NYC schools tested in July with the discredited method, and the results, including which 509 schools were identified with high levels of lead, see here.
Today, Kate Taylor of the NY Times reported that the method that NYC Department of Education has used to test lead in school water by flushing the pipes extensively beforehand is seen as illegitimate by the same scientific experts at Virginia Tech who first revealed the crisis in Flint:
“The results should be thrown into the garbage, and the city should start over,” said Marc Edwards, a civil engineering professor at Virginia Tech who helped uncover dangerously high lead levels in the water in Flint, Mich., touching off scrutiny of drinking water across the country.
Yanna Lambrinidou, an anthropologist who has worked with Dr. Edwards to expose lead contamination in water in Washington, D.C., and elsewhere, and an affiliate faculty member at Virginia Tech’s Department of Science and Technology in Society, said in an email that New York City’s schools “may have just broken the national record for flawed testing.”
I never understood why the DOE’s procedure using pre-flushing would be an accurate way to detect how much lead there may be in the water that settles into pipes and water fountains at the point when schoolchildren actually drank from them.
Subsequently, the DOE switched positions, and when they finally tested all 1500 schools, the results were not encouraging: a startling 509 schools were found to have elevated levels on the first or second draw, even after the flushing exercise noted above:
In a recent NBER paper called Do Low Levels of Blood Lead Reduce Children's Future Test Scores?, written by economists at Brown and Princeton, researchers found that by looking at the blood lead levels of preschool Rhode Island children born between 1997 and 2005 and their subsequent third grade test scores, the higher their blood lead level (BLL) the lower their test scores tended to be: "Using these data, we show that reductions of lead from even historically low levels have significant positive effects on children's reading test scores in third grade.”
Aizer, Currie, Simon, and Vivier, “Lead Exposure and Racial Disparities in Test Scores,” Feb. 7, 2015.