Temporal Variation in Indoor Radon Concentrations Using Environmental Public Health Tracking Data.

ABSTRACT: Indoor radon is the second leading cause of lung cancer in the United States (US) after smoking and the number one for lung cancer in non-smokers. Understanding how indoor radon varies during the year reveals the best time to test to avoid underestimating exposure. This study looks at the temporal variation in 13 years of radon concentrations in buildings located in 46 US states and the District of Columbia (DC). In the dataset, radon concentration varies from 3.7 Bq m -3 (Becquerels per cubic meter) to 52,958.1 Bq m -3 , with an overall mean of 181.4 Bq m -3 . About 35.4% of tests have a radon concentration level equal to or greater than the US Environmental Protection Agency (US EPA) action level 4.0 pCi L -1 (148 Bq m -3 ). 3 Temporal variation in radon concentrations was assessed using the overall monthly mean radon concentration. The highest concentrations were found in January (203.8 Bq m -3 ) and the lowest in July (129.5 Bq m -3 ). Higher monthly mean indoor radon concentrations were found in January, February, and October, and lower in July, August, and June. This result is consistent with findings from other studies and suggests continuing to encourage radon testing throughout the year with an emphasis on testing during the colder months.

Co-Occurrence of Metal Contaminants in United States Public Water Systems in 2013-2015.

The United States Environmental Protection Agency monitors contaminants in drinking water and consolidates these results in the National Contaminant Occurrence Database. Our objective was to assess the co-occurrence of metal contaminants (total chromium, hexavalent chromium, molybdenum, vanadium, cobalt, and strontium) over the years 2013-2015. We used multilevel Tobit regression models with state and water system-level random intercepts to predict the geometric mean of each contaminant occurring in each public water system, and estimated the pairwise correlations of predicted water system-specific geometric means across contaminants. We found that the geometric means of vanadium and total chromium were positively correlated both in large public water systems (r = 0.45, p < 0.01) and in small public water systems (r = 0.47, p < 0.01). Further research may address the cumulative human health impacts of ingesting more than one contaminant in drinking water.

Community drinking water data on the National Environmental Public Health Tracking Network: a surveillance summary of data from 2000 to 2010.

This report describes the available drinking water quality monitoring data on the Centers for Disease Control and Prevention (CDC) National Environmental Public Health Tracking Network (Tracking Network). This surveillance summary serves to identify the degree to which ten drinking water contaminants are present in finished water delivered to populations served by community water systems (CWS) in 24 states from 2000 to 2010. For each state, data were collected from every CWS. CWS are sampled on a monitoring schedule established by the Environmental Protection Agency (EPA) for each contaminant monitored. Annual mean and maximum concentrations by CWS for ten water contaminants were summarized from 2000 to 2010 for 24 states. For each contaminant, we calculated the number and percent of CWS with mean and maximum concentrations above the maximum contaminant level (MCL) and the number and percent of population served by CWS with mean and maximum concentrations above the MCL by year and then calculated the median number of those exceedances for the 11-year period. We also summarized these measures by CWS size and by state and identified the source water used by those CWS with exceedances of the MCL. The contaminants that occur more frequently in CWS with annual mean and annual maximum concentrations greater than the MCL include the disinfection byproducts, total trihalomethanes (TTHM), and haloacetic acids (HAA5); arsenic; nitrate; radium and uranium. A very high proportion of exceedances based on MCLs occurred mostly in very small and small CWS, which serve a year-round population of 3,300 or less. Arsenic in New Mexico and disinfection byproducts HAA5 and TTHM, represent the greatest health risk in terms of exposure to regulated drinking water contaminants. Very small and small CWS are the systems' greatest difficulty in achieving compliance.

Acute Nonoccupational Pesticide-Related Illness and Injury - United States, 2007-2011.

CDC's National Institute for Occupational Safety and Health (NIOSH) collects data on acute pesticide-related illness and injury reported by 12 states (California, Florida, Iowa, Louisiana, Michigan, North Carolina, Nebraska, New Mexico, New York, Oregon, Texas, and Washington). This report summarizes the data on illnesses and injuries arising from nonoccupational exposure to conventional pesticides that were reported during 2007-2011. Conventional pesticides include insecticides, herbicides, fungicides, and fumigants. They exclude disinfectants (e.g., chlorine and hypochlorites) and biological pesticides (1). This report is a part of the Summary of Notifiable Noninfectious Conditions and Disease Outbreaks - United States, which encompasses various surveillance years but is being published in 2016 (2). The Summary of Notifiable Noninfectious Conditions and Disease Outbreaks appears in the same volume of MMWR as the annual Summary of Notifiable Infectious Diseases (3). In a separate report, data on illnesses and injuries from occupational exposure to conventional pesticides during 2007-2011 are summarized (4).

U.S. census unit population exposures to ambient air pollutants.

BACKGROUND: Progress has been made recently in estimating ambient PM(2.5) (particulate matter with aerodynamic diameter < 2.5 µm) and ozone concentrations using various data sources and advanced modeling techniques, which resulted in gridded surfaces. However, epidemiologic and health impact studies often require population exposures to ambient air pollutants to be presented at an appropriate census geographic unit (CGU), where health data are usually available to maintain confidentiality of individual health data. We aim to generate estimates of population exposures to ambient PM(2.5) and ozone for U.S. CGUs. METHODS: We converted 2001-2006 gridded data, generated by the U.S. Environmental Protection Agency (EPA) for CDC's (Centers for Disease Control and Prevention) Environmental Public Health Tracking Network (EPHTN), to census block group (BG) based on spatial proximities between BG and its four nearest grids. We used a bottom-up (fine to coarse) strategy to generate population exposure estimates for larger CGUs by aggregating BG estimates weighted by population distribution. RESULTS: The BG daily estimates were comparable to monitoring data. On average, the estimates deviated by 2 µg/m(3) (for PM(2.5)) and 3 ppb (for ozone) from their corresponding observed values. Population exposures to ambient PM(2.5) and ozone varied greatly across the U.S. In 2006, estimates for daily potential population exposure to ambient PM(2.5) in west coast states, the northwest and a few areas in the east and estimates for daily potential population exposure to ambient ozone in most of California and a few areas in the east/southeast exceeded the National Ambient Air Quality Standards (NAAQS) for at least 7 days. CONCLUSIONS: These estimates may be useful in assessing health impacts through linkage studies and in communicating with the public and policy makers for potential intervention.

Fish and shellfish consumption estimates and perceptions of risk in a cohort of occupational and recreational fishers of the Chesapeake Bay.

Exposure to persistent, bioaccumulating substances, through the consumption of contaminated fish is of concern in human populations. Consumption may be particularly high for subsistence, commercial, and recreational fishers, so it is important to obtain accurate consumption estimates to assess risks in these groups. The objectives of the work reported here were: to obtain estimates of fish and shellfish consumption (meals and portion size) in an occupational cohort; to determine what percentage of the consumption was from local fish; to evaluate reliability of two methods of reporting fish and shellfish consumption; and to examine risk perceptions in relation to consumption. Subjects included 99 recreational and occupational fishers in the Chesapeake Bay area, Virginia, who were recruited for a cohort study of estuary-associated syndrome. Subjects reported average fish and shellfish consumption (all species) on a weekly, monthly or yearly basis, and were asked species-specific information, which was summed. The median number of fish meals consumed a year was significantly different depending on the method used, 52 (interquartile range, IQR:24-104) (average method) and 65 (IQR:30-117) (sum of species-specific), respectively. Shellfish estimates were 24 (IQR:12-52) (average) and 47 (IQR:31-84) (sum) meals a year. Of those who consumed fish, participants reported an average meal size of 8.9+/-3.38 oz. (median 8 oz, range 4-16) with close to 70% of fish consumed self-caught and 50% from Virginia waters. Using multiple regression, occupation, and risk perceptions were found to be significantly correlated with fish consumption levels, and consumption of fish from locations under advisory.

A Norwalk-like virus outbreak on the Appalachian Trail.

In May and June 1999, an outbreak of acute gastrointestinal illness occurred among long-distance hikers on the Appalachian Trail between Catawba and Troutville, Virginia. An investigation found that 45 out of 70 hikers had become ill within two days of arriving in Catawba, Virginia. Water samples were collected from a general store frequented by the hikers and from several nearby buildings and a popular all-you-can-eat restaurant. Symptoms were consistent with those caused by Norwalk-like viruses, and laboratory diagnosis detected Norwalk-like viruses in stool and serum specimens. People who consumed food items prepared at the general store were almost twice as likely to become ill as persons who did not consume those foods. Environmental sampling of water from the taps inside and outside the general store and from several surrounding establishments in Catawba found contamination by fecal coliform bacteria but not by Norwalk-like virus. Since several hikers reported illness prior to arriving at Catawba, person-to-person transmission of a highly contagious agent such as Norwalk-like virus could not be ruled out. Poor sanitation, scarce water supplies, and crowding can increase the risk of gastrointestinal illness among long-distance hikers.