Rebecca Perritt

The Team Study - Personal Exposures to Toxic-Substances in Air, Drinking-Water, and Breath of 400 Residents of New-Jersey, North-Carolina, and North-Dakota:

EPAs TEAM Study has measured exposures to 20 volatile organic compounds in personal air, outdoor air, drinking water, and breath of approximately 400 residents of New Jersey, North Carolina, and North Dakota. All residents were selected by a probability sampling scheme to represent 128,000 inhabitants of Elizabeth and Bayonne, New Jersey, 131,000 residents of Greensboro, North Carolina, and 7000 residents of Devils Lake, North Dakota. Participants carried a personal monitor to collect two 12-hr air samples and gave a breath sample at the end of the day. Two consecutive 12-hr outdoor air samples were also collected on identical Tenax cartridges in the backyards of some of the participants. About 5000 samples were collected, of which 1500 were quality control samples. Ten compounds were often present in personal air and breath samples at all locations. Personal exposures were consistently higher than outdoor concentrations for these chemicals and were sometimes 10 times the outdoor concentrations. Indoor sources appeared to be responsible for much of the difference. Breath concentrations also often exceeded outdoor concentrations and correlated more strongly with personal exposures than with outdoor concentrations. Some activities (smoking, visiting dry cleaners or service stations) and occupations (chemical, paint, and plastics plants) were associated with significantly elevated exposures and breath levels for certain toxic chemicals. Homes with smokers had significantly increased benzene and styrene levels in indoor air. Residence near major point sources did not affect exposure.

Aggressive vs. conservative phototherapy for infants with extremely low birth weight

BACKGROUND It is unclear whether aggressive phototherapy to prevent neurotoxic effects of bilirubin benefits or harms infants with extremely low birth weight (1000 g or less). METHODS We randomly assigned 1974 infants with extremely low birth weight at 12 to 36 hours of age to undergo either aggressive or conservative phototherapy. The primary outcome was a composite of death or neurodevelopmental impairment determined for 91% of the infants by investigators who were unaware of the treatment assignments. RESULTS Aggressive phototherapy, as compared with conservative phototherapy, significantly reduced the mean peak serum bilirubin level (7.0 vs. 9.8 mg per deciliter [120 vs. 168 micromol per liter], P<0.01) but not the rate of the primary outcome (52% vs. 55%; relative risk, 0.94; 95% confidence interval [CI], 0.87 to 1.02; P=0.15). Aggressive phototherapy did reduce rates of neurodevelopmental impairment (26%, vs. 30% for conservative phototherapy; relative risk, 0.86; 95% CI, 0.74 to 0.99). Rates of death in the aggressive-phototherapy and conservative-phototherapy groups were 24% and 23%, respectively (relative risk, 1.05; 95% CI, 0.90 to 1.22). In preplanned subgroup analyses, the rates of death were 13% with aggressive phototherapy and 14% with conservative phototherapy for infants with a birth weight of 751 to 1000 g and 39% and 34%, respectively (relative risk, 1.13; 95% CI, 0.96 to 1.34), for infants with a birth weight of 501 to 750 g. CONCLUSIONS Aggressive phototherapy did not significantly reduce the rate of death or neurodevelopmental impairment. The rate of neurodevelopmental impairment alone was significantly reduced with aggressive phototherapy. This reduction may be offset by an increase in mortality among infants weighing 501 to 750 g at birth. (ClinicalTrials.gov number, NCT00114543.)

Population-Based Analysis of the Effect of the Northridge Earthquake on Cardiac Death in Los Angeles County, California

OBJECTIVES We sought to determine whether a natural disaster affected total cardiovascular mortality and coronary mortality in an entire population. BACKGROUND The effect of the January 17, 1994 Northridge Earthquake (NEQ) on all deaths and causes of deaths within the entire population of Los Angeles County is unknown. The purposes of our study were to analyze all deaths in this entire population before, during and after the NEQ and to determine whether the NEQ temporally and spatially altered death due to cardiovascular disease. METHODS We analyzed all death certificate data (n = 19,617) from Los Angeles County during January of 1992, 1993 (control periods) and 1994, using International Classification of Diseases, 9th Revision codes for ischemic heart disease (IHD) and atherosclerotic cardiovascular disease (ASCVD), as well as other causes of death. RESULTS There was an average of 73 deaths per day due to IHD and ASCVD during January 1 to 16, 1994; this increased to 125 on the day of the NEQ, and then decreased to 57 deaths per day from January 18 to 31 (p < 0.00001, before NEQ vs. day of NEQ; after NEQ vs. day of NEQ; and before NEQ vs. after NEQ). The NEQ was associated with an increase in deaths due to myocardial infarction and trauma but not cardiomyopathy, hypertensive heart disease, valvular heart disease, cerebrovascular disease or noncardiovascular causes. Based on plots of daily deaths due to IHD and ASCVD, the decrease in deaths during the 14 days after the NEQ (-144) overcompensated for the increase on the day of the NEQ (+55). Geographic analysis revealed a redistribution of deaths due to IHD and ASCVD toward the epicenter on the day of the NEQ. CONCLUSIONS When an entire population simultaneously experiences a major environmental stress, there is an increase in death due to coronary artery disease (but not other cardiac causes), followed by a decrease that overcompensates for the excess of death. The overcompensation may represent a residual population that is more resistant to stress or a possible preconditioning effect of the stress, or both. This study supports the concept that cardiovascular events within an entire population can be triggered by a shared stress.

The California TEAM study: Breath concentrations and personal exposures to 26 volatile compounds in air and drinking water of 188 residents of Los Angeles, Antioch, and Pittsburg, CA

Abstract The U.S. EPA carried out a study of personal exposures to 26 volatile organic chemicals in the air, drinking water, and exhaled breath of 188 California residents in 1984. Sixteen chemicals were often found above quantifiable limits in the personal air samples, but only the four trihalomethanes were often found in drinking water. The highest exposures were to 1,1,1-trichloroethane, para-dichlorobenzene, xylenes, benzene, and tetrachloroethylene. Indoor air concentrations generally exceeded outdoor air concentrations, particularly at the higher percentiles. Breath concentrations of eight chemicals showed significant correlations with preceding personal air concentrations in the two visits to Los Angeles. Smoking, employment, and automobile-related activities were identified as important sources of personal exposure to a number of target compounds.

National Human Exposure Assessment Survey (NHEXAS): distributions and associations of lead, arsenic, and volatile organic compounds in EPA Region 5

The National Human Exposure Assessment Survey (NHEXAS) Phase I field study conducted in EPA Region 5 provides extensive exposure data on approximately 250 study participants selected via probability sampling. Associated environmental media and biomarker (blood, urine) concentration data were also obtained to aid in the understanding of relationships of the exposures to both contaminant sources and doses. Distributional parameters for arsenic (As), lead (Pb), and four volatile organic compounds (VOCs)—benzene, chloroform, tetrachloroethylene, and trichloroethylene—were estimated for each of the relevant media using weighted data analysis techniques. Inter-media associations were investigated through correlation analysis, and longitudinal correlations and models were used to investigate longitudinal patterns. Solid food appeared to be a major contributor to urine As levels, while Pb levels in household (HH) dust, personal air, and beverages all were significantly associated with blood Pb levels. Relatively high (>0.50) longitudinal correlations were observed for tap water Pb and As, as compared to only moderate longitudinal correlations for the personal air VOCs.

Patterns of HIV risk and alcohol use among African-American crack abusers.

Although the association between heavy alcohol use and HIV risk has been studied in treatment populations, we know little about patterns of alcohol use and HIV risk among out-of-treatment African-American drug users. This study examines the extent to which alcohol use affects HIV risk in a sample of 495 African-American crack users who did not inject drugs. We present differences between levels of alcohol and crack use with regard to sexual practices (including sex while impaired), number of partners, frequency of sexual activity, and condom use. The findings suggest an intimate relationship between alcohol use, crack use, and sexual risks for HIV infection. Respondents who reported frequent use (15-30 days in the last 30 days) of alcohol, crack, or both displayed significantly greater risk than those who reported less than frequent use.

Predictors of Death or Bronchopulmonary Dysplasia in Preterm Infants with Respiratory Failure

Objectives:To identify the variables that predict death/physiologic bronchopulmonary dysplasia (BPD) in preterm infants with severe respiratory failure.Study Design:The study was a secondary analysis of data from the NICHD Neonatal Research Network trial of inhaled nitric oxide (iNO) in preterm infants. Stepwise logistic regression models and Classification and Regression Tree (CART) models were developed for the outcome of death or physiologic BPD (O2 at 36 weeks post-menstrual age).Result:Death and/or BPD was associated with lower birth weight, higher oxygen requirement, male gender, additional surfactant doses, higher oxygenation index and outborn status, but not the magnitude of response in PaO2 to iNO. The positive predictive value of the CART model was 82% at 95% sensitivity.Conclusions:The major factors associated with death/BPD were an increased severity of respiratory failure, lower birth weight, male gender and outborn status, but not the magnitude of initial response to iNO.

Influence of clinical status on the association between plasma total and unbound bilirubin and death or adverse neurodevelopmental outcomes in extremely low birth weight infants

Objectives:  To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants.

Trends in the use of pharmacotherapies for acute myocardial infarction among physicians who design and/or implement randomized trials versus physicians in routine clinical practice: the MILIS-TIMI experience

BACKGROUND Although studies have documented that randomized, controlled trials (RCTs) have a measurable influence on clinical practice, investigators have uncovered important deficiencies in the application of RCT findings to the management of acute myocardial infarction (AMI). Little is known about the extent to which physicians who design and/or implement clinical trials differ from physicians in routine practice in their translation of the literature. METHODS Our aims were to (1) evaluate recent trends in selected treatments of AMI in relation to the publication of RCTs, statistical overviews, and task-force guidelines, and (2) compare prescribing practices in AMI management between physicians in routine clinical practice and physicians who design and/or implement RCTs. We reviewed the use of aspirin, beta-blockers, angiotensin-converting enzyme inhibitors, and calcium channel blockers on entry and at discharge in patients enrolled in the MILIS, TIMI 1, 2, 4, 5, 6, and 9B trials with ST-elevation (and depression in MILIS) myocardial infarction for a period approaching 2 decades (August 1978 to September 1995). We hypothesized that physicians who participate in RCTs apply the findings of the published literature more promptly and thoroughly than physicians in routine practice. RESULTS Use of aspirin, beta-blockers, and angiotensin converting enzyme inhibitors exhibited a statistically significant time-related increase at discharge and, excepting beta-blockers, at enrollment across the trials. Prescription of calcium channel blockers showed a statistically significant decrease at discharge only. For all medications under study, increases and decreases in use associated with publication of clinical data occurred earlier and more steeply for the discharge cohort (prescriptions by physicians participating in RCTs) than for the enrollment cohort (prescriptions by physicians in routine practice). Recent prescribing practices (1994 to 1995) among RCT investigators and their colleagues have higher concordance with published findings than those of physicians in routine practice. CONCLUSIONS Physicians who design and/or implement RCTs translate the results of the medical literature more promptly and to a greater extent than physicians in routine clinical practice. Differences between different physician classes need to be studied further amid efforts to reconfigure health care delivery that currently favor more dominant roles for primary care physicians.

Comparison of indoor and outdoor residential levels of volatile organic chemicals in five U.S. geographical areas

Abstract Matched pairs of indoor and outdoor air samples from residences in Greensboro, NC; Baton Rouge/ Geismar, LA; Deer Park/Pasadena, TX; Elizabeth/Bayonne, NJ: Antioch/W. Pittsburg, CA; and several small communities in the Los Angeles area were collected and analyzed for over 20 volatile organic compounds during the period from 1981 to 1984. Indoor (I) medians and maximum levels were higher than the corresponding outdoor (O) concentrations over the large majority of chemicals studied. In some cases, e.g., chloroform, dichlorobenzenes, and tetrachloroethylene, the median ratios (I/O) were greater than 10.