Navigation Links
Children's blood lead levels linked to lower test scores

DURHAM, N.C. -- Exposure to lead in early childhood significantly contributes to lower performances on end-of-grade (EOG) reading tests among minority and low-income children, according to researchers at Duke University and North Carolina Central University.

"We found a clear dose-response pattern between lead exposure and test performance, with the effects becoming more pronounced as you move from children at the high end to the low end of the test-score curve," said lead investigator Marie Lynn Miranda, director of the Children's Environmental Health Initiative (CEHI) at Duke's Nicholas School of the Environment.

"Given the higher average lead exposure experienced by African-American children in the United States, our results show that lead does in fact explain part of the observed achievement gap that blacks, children of low socioeconomic status and other disadvantaged groups continue to exhibit in school performance in the U.S. education system, compared to middle- and upper-class whites," Miranda said.

The study, published online in the peer-reviewed journal NeuroToxicology, linked data on blood-lead levels from the North Carolina Childhood Lead Poisoning Prevention Program surveillance registry to EOG reading test scores for 4th graders in all 100 of the state's counties.

Researchers used innovative methods, including the use of a statistical approach called quantile regression, to measure the contribution of lead exposure to declining levels in children's EOG scores.

Their analyses revealed that early childhood exposure to lead, the family's poverty status and parental education all account for test-score declines. On average, exposure to lead accounts for between 7 percent and 16 percent of the decline, with the larger declines associated with higher blood-lead levels.

By comparison, they found the family's poverty status, as indicated by enrollment in a free or reduced-price school lunch program, accounts for 25 percent to 28 percent of EOG declines.

And parental education accounts for the largest portion of the drop in test scores, between 58 percent and 65 percent of the total.

"This demonstrates the particular vulnerabilities of socioeconomically and environmentally disadvantaged children," said Miranda, an associate professor at the Nicholas School and Duke Medical School's department of pediatrics. "Children who experience these cumulative deficits are especially disadvantaged when they enter the school system."

The team's analysis showed that children already at the low end of the test-score curve were more greatly affected by lead exposure the greater the exposure, the greater the impact on their scores. However, downward shifts were also documented in exposed children at the high end of the EOG curve. This is important, the study noted, because EOG scores are used to place students into advanced and intellectually gifted (AIG) programs at schools across the United States.

"Our findings show that even low-level lead exposure can push some children out of the score range that would make them eligible for these special programs," Miranda said. "To the extent that low-income and minority children are systematically exposed to more lead, AIG programs become less economically and racially diverse."


Contact: Tim Lucas
Duke University

Related biology news :

1. Super sticky barnacle glue cures like blood clots
2. Blood vessel builders
3. Blood counts are clues to human disease
4. New blood-thinning drug safer than rat poison
5. University of Iowa scientists use blood-brain barrier as therapy delivery system
6. New blood tests promise simple, cost-effective diagnosis of gastrointestinal cancers
7. Diesel exhaust is linked to cancer development via new blood vessel growth
8. New information about how fat increases blood pressure could help identify those at risk
9. Gene signal GS-101 data shows safe and effective inhibition of ophthalmic blood vessel growth
10. Blood-flow metabolism mismatch predicts pancreatic tumor aggressiveness
11. Glow-in-the-dark red blood cells made from human stem cells
Post Your Comments:
(Date:5/16/2016)... YORK , May 16, 2016   EyeLock ... solutions, today announced the opening of an IoT Center ... to strengthen and expand the development of embedded iris ... an unprecedented level of convenience and security with unmatched ... authenticate one,s identity aside from DNA. EyeLock,s platform uses ...
(Date:4/28/2016)... -- First quarter 2016:   , Revenues ... first quarter of 2015 The gross margin was 49% ... and the operating margin was 40% (-13) Earnings per ... from operations was SEK 249.9 M (21.2) , Outlook ... 7,000-8,500 M. The operating margin for 2016 is estimated ...
(Date:4/15/2016)... DUBLIN , April 15, 2016 ... of the,  "Global Gait Biometrics Market 2016-2020,"  report ... ) , ,The global gait ... CAGR of 13.98% during the period 2016-2020. ... movement angles, which can be used to compute ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... ClinCapture, the only free ... and will showcase its product’s latest features from June 26 to June 30, ... poster on Disrupting Clinical Trials in The Cloud during the conference. DIA ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity Products, ... tools designed, tuned and optimized exclusively for Okuma CNC machining centers at The ... of a collaboration among several companies with expertise in toolholding, cutting tools, machining ...
(Date:6/23/2016)... 23, 2016 adds ... to its pharmaceuticals section with historic and forecast ... much more. Complete report on the ... profiling 15 companies and supported with 261 tables ... . The Global Cell Culture ...
(Date:6/22/2016)... Research and Markets has announced the addition of the "Biomarkers: ... The global biomarkers market has grown ... market is expected to grow at a five-year compound annual growth ... billion in 2015 to $96.6 billion in 2020. ... 2020) are discussed. As well, new products approved in 2013 and ...
Breaking Biology Technology: