Environmental Lead after Hurricane Katrina: Implications for Future Populations

Article excerpt

BACKGROUND: As a result of Hurricane Katrina, > 100,000 homes were destroyed or damaged and a significant amount of sediment was deposited throughout the city of New Orleans, Louisiana. Researchers have identified the potential for increased lead hazards from environmental lead contamination of soils.

OBJECTIVES: We assessed the distribution of residential soil and dust lead 2 years poststorm and compared soil lead before and after the storm.

METHODS: We conducted a cross-sectional study in New Orleans in which households were selected by stratified random sampling. A standard residential questionnaire was administered, and lead testing was performed for both the interior and exterior of homes. Logistic regression was used to identify significant predictors of interior and exterior lead levels in excess of allowable levels.

RESULTS: One hundred nine households were enrolled; 61% had at least one lead measurement above federal standards. Of homes with bare soil, 47% had elevated lead and 27% had levels exceeding 1,200 ppm. Housing age was associated with soil lead, and housing age and soil lead were associated with interior lead. Race, income, and ownership status were not significantly associated with either interior or exterior lead levels. The median soil lead level of 560 ppm was significantly higher than the median level of samples collected before Hurricane Katrina.

CONCLUSIONS: The high prevalence (61%) of lead above recommended levels in soil and dust samples in and around residences raises concern about potential health risks to the New Orleans population, most notably children. 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.

KEY WORDS: children's health, environmental exposures, housing, lead exposure, soil pollutants. Environ Health Perspect 120:180-184 (2012). http://dx.doi.org/l0.1289/ehp.1103774 [Online 3 November 2011]

When Hurricane Katrina Hooded the city of New Orleans, Louisiana, and adjacent areas in August 2005, one of many environmental health concerns was the possibility of widespread contamination of soils and sediments. To assess the hurricane's impact, the U.S. Environmental Protection Agency (EPA) and the Louisiana Department of Environmental Quality initiated an investigation into the floodwater sediment contamination in residential neighborhoods both before the floodwaters receded and before cleanup. Sampling results indicated that residential soils contained lead; however, the U.S. EPA found that the hurricane did not significantly affect the distribution of lead because the post-hurricane geography of lead distribution resembled prehurricane distributions (U.S. EPA 2005). Another lead assessment, conducted in 2006, reported a 46% decrease in median soil lead from pre-Katrina levels (Zahran er al. 2010). Both of these studies were conducted in the immediate aftermath of Hurricane Katrina and preceded the extensive renovation effort that would be required to rebuild the city.

A 2007 report by the Agency for Toxic Substances and Disease Registry (ATSDR) highlighted the potential risk of lead exposure to families returning to New Orleans in light of the extensive amount of renovation and demolition that would be required to rebuild the city. According to the 2000 U.S. Census, > 100,000 homes in New Orleans were built before 1950, an estimated 83% of which have lead hazards (ATSDR 2007). The report concluded by stating that despite surveys indicating no increase in environmental lead levels, the actual extent of lead hazards would he determined oniy after soil data collected subsequent to reconstruction activities became available (ATSDR 2007). A recently published survey 0f schoolyard soil also suggested the need for more extensive assessment of residential lead hazards (Presley et al. …