In the United States, 6,868 cases of legionellosis were reported to the Center for Disease Control and Prevention in 2009−2010. Of these reports, it is estimated that 84% are caused by the microorganism Legionella pneumophila Serogroup (Sg) 1. Legionella spp. have been isolated and recovered from a variety of natural freshwater environments. Human exposure to L. pneumophila Sg1 may occur from aerosolization and subsequent inhalation of household and facility water. In this study, two primer/probe sets (one able to detect L. pneumophila and the other L. pneumophila Sg1) were determined to be highly sensitive and selective for their respective targets. Over 272 water samples, collected in 2009 and 2010 from 68 public and private water taps across the United States, were analyzed using the two qPCR assays to evaluate the incidence of L. pneumophila Sg1. Nearly half of the taps showed the presence of L. pneumophila Sg1 in one sampling event, and 16% of taps were positive in more than one sampling event. This study is the first United States survey to document the occurrence and colonization of L. pneumophila Sg1 in cold water delivered from point of use taps.

It has been suggested that Mycobacterium avium subspecies paratuberculosis has a role in Crohn's disease. The organism may be acquired but is difficult to culture from the environment. We describe a quantitative PCR (qPCR) method to detect M. avium subsp. paratuberculosis in drinking water and the results of its application to drinking water and faucet biofilm samples collected in the United States.

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Nontuberculous mycobacteria (NTMs) are environmental microorganisms that can cause infections in humans, primarily in the lung and soft tissue. The prevalence of NTM-associated diseases is increasing in the United States. Exposure to NTMs occurs primarily through human interactions with water (especially aerosolized). Potable water from sites across the U.S. was collected to investigate the presence of NTM. Water from 68 taps was sampled 4 times over the course of 2 years. In total, 272 water samples were examined for NTM using a membrane filtration, culture method. Identification of NTM isolates was accomplished by polymerase chain reaction (PCR) amplification of the 16S rRNA and hsp65 genes. NTMs were detected in 78% of the water samples. The NTM species detected most frequently were: Mycobacterium mucogenicum (52%), Mycobacterium avium (30%), and Mycobacterium gordonae (25%). Of the taps that were repeatedly positive for NTMs, the species M. avium, M. mucogenicum, and Mycobacterium abscessus were found to persist most frequently. This study also observed statistically significant higher levels of NTM in chloraminated water than in chlorinated water.

Most studies of the relationship between maternal residential proximity to sources of environmental pollution and congenital cardiovascular malformations have combined heart defects into one group or broad subgroups. The current case-control study examined whether risk of conotruncal heart defects, including subsets of specific defects, was associated with maternal residential proximity to hazardous waste sites and industrial facilities with recorded air emissions. Texas Birth Defects Registry cases were linked to their birth or fetal death certificate. Controls without birth defects were randomly selected from birth certificates. Distances from maternal addresses at delivery to National Priority List (NPL) waste sites, state superfund waste sites, and Toxic Release Inventory (TRI) facilities were determined for 1244 cases (89.5% of those eligible) and 4368 controls (88.0%). Living within 1 mile of a hazardous waste site was not associated with risk of conotruncal heart defects [adjusted odds ratio (aOR) = 0.83, 95% confidence interval (CI) = 0.54, 1.27]. This was true whether looking at most types of defects or waste sites. Only truncus arteriosus showed statistically elevated ORs with any waste site (crude OR: 2.80, 95% CI 1.19, 6.54) and with NPL sites (crude OR: 4.63, 95% CI 1.18, 13.15; aOR 4.99, 95% CI 1.26, 14.51), but the latter was based on only four exposed cases. There was minimal association between conotruncal heart defects and proximity to TRI facilities (aOR = 1.10, 95% CI = 0.91, 1.33). Stratification by maternal age or race/ethnic group made little difference in effect estimates for waste sites or industrial facilities. In this study population, maternal residential proximity to waste sites or industries with reported air emissions was not associated with conotruncal heart defects or its subtypes in offspring, with the exception of truncus arteriosus.