Lead levels elevated in New Orleans homes following Hurricane Katrina
MedWire News: Study findings show that following the aftermath of Hurricane Katrina nearly two-thirds of homes in affected areas have lead levels above recommended safe limits, raising concerns about potential health risks for the New Orleans population.
"New Orleans children are at a risk for elevated blood lead levels, including children who were not considered at high risk previously and for whom lead reduction has been considered a public health success," say Felicia Rabito (Tulane School of Public Health and Tropical Medicine, New Orleans, Louisiana, USA) and colleagues.
During 2007-2008, the researchers administered a standard residential questionnaire and performed lead testing of both the interior and exterior of 109 homes located in New Orleans.
Using standard Department of Housing and Urban Development (HUD)/Environmental Protection Agency (EPA) cut-off points of more than 40 µg/ft2 for floor dust and over 250 µg/ft2 for windowsill dust, 50.5% of homes had at least one interior sample containing elevated levels of lead.
Furthermore, 46.7% of 90 homes with bare soil had levels greater than 400 ppm, with 26.7% showing levels in excess of 1200 ppm. When both interior and exterior samples were considered, 61.4% of homes had least one measurement in excess of the HUD/EPA standard.
After controlling for housing age, soil lead levels remained significantly associated with interior lead levels above HUD/EPA recommendations.
When the researchers compared soil lead levels for pre- and post-Hurricane Katrina time periods, they found that in the 2000 survey soil lead ranged from 25 to 1789 ppm while in the 2007-2008 survey the range was significantly increased, from 10 to 24,000 ppm.
In addition, medial soil lead levels post-Hurricane Katrina were 37% higher than those before the event, at 560 versus 408 ppm.
Regression analysis revealed that the age of housing was the only factor significantly associated with elevated soil lead. Age of housing and elevated soil lead were significantly associated with increased interior lead levels.
Rabito and team note that the widespread lead contamination around homes was unexpected, given the low proportion of minority homeowners - who would normally be considered to have a low risk for lead exposure - included in the study.
"Lead contamination may be a result of the unprecedented amount of home renovation and demolition that was required as a result of Hurricane Katrina damage both in high and low income neighborhoods," say the authors.
"Steps should be taken to mitigate the risk of exposure to lead-contaminated soil and dust. Further research is needed to quantify the possible contribution of reconstruction activities to environmental lead levels," write the authors in the journal Environmental Health Perspectives.
By Ingrid Grasmo