Molds and mycotoxins in dust from water-damaged homes in New Orleans after hurricane Katrina.

UNLABELLED: Dust collected in New Orleans homes mold-contaminated because of the flooding after hurricane Katrina was analyzed for molds and mycotoxins. The mycoflora was studied by cultivation and quantitative PCR for selected molds. The most commonly found mold taxa were Aspergillus, Cladosporium, and Penicillium. Verrucarol, a hydrolysis product of macrocyclic trichothecenes predominately produced by Stachybotrys spp. was identified in three dust samples by gas chromatography-tandem mass spectrometry, and sterigmatocystin (produced by various Aspergillus spp.) was found in two samples by high pressure liquid chromatography-tandem mass spectrometry. This is the first demonstration of mycotoxins in Katrina-associated dust samples. The analytical methods used represent valuable tools in further studies on bioaerosol exposure and health risks. PRACTICAL IMPLICATIONS: In the aftermath of natural disasters like hurricane Katrina water-damages on infrastructure and public and private property are often associated with health risks for remediation workers and returning residents. In the case of New Orleans evaluations of health hazards, health studies, and assessments of bioaerosol have been conducted previously. However, until now mycotoxins have not been addressed. Our study shows, for the first time, the presence of mycotoxins in dust collected in houses in New Orleans mold-contaminated because of the hurricane Katrina. The results may highlight the potential health threats posed by mold aerosols in post-disaster inhabited areas.

Few Associations Found between Mold and Other Allergen Concentrations in the Home versus Skin Sensitivity from Children with Asthma after Hurricane Katrina in the Head-Off Environmental Asthma in Louisiana Study.

Mold and other allergen exposures exacerbate asthma symptoms in sensitized individuals. We evaluated allergen concentrations, skin test sensitivities, and asthma morbidity for 182 children, aged 4-12 years, with moderate to severe asthma, enrolled 18 months after Katrina, from the city of New Orleans and the surrounding parishes that were impacted by the storm, into the Head-off Environmental Asthma in Louisiana (HEAL) observational study. Dust (indoor) and air (indoor and outdoor) samples were collected at baseline of 6 and 12 months. Dust samples were evaluated for dust mite, cockroach, mouse, and Alternaria by immunoassay. Air samples were evaluated for airborne mold spore concentrations. Overall, 89% of the children tested positive to ≥1 indoor allergen, with allergen-specific sensitivities ranging from 18% to 67%. Allergen concentration was associated with skin sensitivity for 1 of 10 environmental triggers analyzed (cat). Asthma symptom days did not differ with skin test sensitivity, and surprisingly, increased symptoms were observed in children whose baseline indoor airborne mold concentrations were below median levels. This association was not observed in follow-up assessments. The lack of relationship among allergen levels (including mold), sensitivities, and asthma symptoms points to the complexity of attempting to assess these associations during rapidly changing social and environmental conditions.