Dale P Sandler

University of Bergen, Bergen, Hordaland, Norway

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Publications (298)1524.41 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Tamoxifen has been US Food and Drug Administration-approved for primary prevention of breast cancer since 1998 but has not been widely adopted, in part because of increased risk of serious side effects. Little is known about the risk-benefit profiles of women who use chemoprevention outside of a clinical trial. We examined characteristics associated with initiation and discontinuation of tamoxifen for primary prevention of breast cancer within a large cohort of women with a first-degree family history of breast cancer. This research was conducted within The Sister Study, a cohort of 50884 US and Puerto Rican women age 35 to 74 years enrolled from 2003 to 2009. Eligible women were breast cancer-free at enrollment and had a sister who had been diagnosed with breast cancer. Participants reported tamoxifen use, ages started and stopped taking tamoxifen, and total duration of use at enrollment. We identified 788 tamoxifen users and 3131 nonusers matched on age and year of enrollment who had no history of contraindicating factors (stroke, transient ischemic attack, cataract, endometrial or uterine cancer). Characteristics associated with tamoxifen initiation were evaluated with multivariable conditional logistic regression. All statistical tests were two-sided. Based on published risk-benefit indices, 20% of women who used tamoxifen had insufficient evidence that the benefits of tamoxifen outweigh the risk of serious side effects. After 4.5 years, 46% of women had discontinued tamoxifen. While the majority of women who used tamoxifen for primary prevention of breast cancer were likely to benefit, substantial discontinuation of tamoxifen before five years and use by women at risk of serious side effects may attenuate benefits for breast cancer prevention. Published by Oxford University Press 2014.
    JNCI Journal of the National Cancer Institute 01/2015; 107(1). · 15.16 Impact Factor
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    ABSTRACT: Pesticides have been associated with Parkinson's disease (PD), and protective gloves and workplace hygiene can reduce pesticide exposure. We assessed whether use of gloves and workplace hygiene modified associations between pesticides and PD. The Farming and Movement Evaluation (FAME) study is a nested case–control study within the Agricultural Health Study. Use of protective gloves, other PPE, and hygiene practices were determined by questionnaire (69 cases and 237 controls were included). We considered interactions of gloves and hygiene with ever-use of pesticides for all pesticides with ≥ 5 exposed and unexposed cases and controls in each glove-use stratum (paraquat, permethrin, rotenone, and trifluralin). 61% of respondents consistently used protective gloves and 87% consistently used ≥ 2 hygiene practices. Protective glove use modified the associations of paraquat and permethrin with PD: neither pesticide was associated with PD among protective glove users, while both pesticides were associated with PD among non-users (paraquat OR 3.9 [95% CI 1.3, 11.7], interaction p = 0.15; permethrin OR 4.3 [95% CI 1.2, 15.6] interaction p = 0.05). Rotenone was associated with PD regardless of glove use. Trifluralin was associated with PD among participants who used < 2 hygiene practices (OR 5.5 [95% CI 1.1, 27.1]) but was not associated with PD among participants who used 2 or more practices (interaction p = 0.02). Although sample size was limited in the FAME study, protective glove use and hygiene practices appeared to be important modifiers of the association between pesticides and PD and may reduce risk of PD associated with certain pesticides.
    Environment International 11/2014; · 5.66 Impact Factor
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    ABSTRACT: Background: The objective of this study is to evaluate the relationship between occupational physical activity and leisure-time physical activity in the Sister Study, a cohort of United States and Puerto Rican women Methods: We performed a cross-sectional analysis of 27,487 Sister Study women employed for a minimum of 1 year at Sister Study baseline enrollment. Occupational physical activity was self-reported as mostly sitting, mostly standing, mostly walking or heavy labor. We estimated the weekly energy expended for all reported leisure-time activities (sports, exercise, and non-occupational daily activities) in metabolic equivalent (MET) hours per week. Log-binomial regression was used to model the relationship between occupational physical activity level and leisure-time physical activity (7.5 MET hours per week - the minimal activity recommended by the U.S government), adjusting for potential confounders. Results: Approximately 17% of women (n= 4,614) did not meet the minimum recommended leisure-time physical activity level. Compared with women in more active jobs, women in mostly sedentary jobs had a 23% lower prevalence (RR: 0.77, 95%CI: 0.64-0.90) of meeting minimal physical activity guidelines. The association between occupational physical activity and leisure-time physical activity was not modified by age, education, or income. Conclusions: Occupational sitting is associated with leisure-time physical inactivity in women aged 35-74 years. The results of this study suggest that women in mostly sedentary jobs should be targeted for health promotion strategies that encourage physical activity outside of the workplace.
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
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    ABSTRACT: Background: Physical activity is a modifiable risk factor for breast cancer. An inverse association between recreational physical activity and breast cancer has been well established in epidemiologic studies. It is not clear, however, if occupational physical activity reduces the risk of breast cancer. The objective of this study was to evaluate the association between occupational physical activity and breast cancer risk in a prospective study of 47,775 women enrolled in the Sister Study between 2004 and 2009. Methods: Data on lifetime occupational history and suspected risk factors for breast cancer were collected at enrollment. For each job held after the age of 18, study participants were asked to characterize their physical activity. Active work was defined as working in a job that required continuous walking or heavy manual labor. The association between occupational physical activity and breast cancer risk was evaluated using multivariable Cox proportional hazards regression models. Results: A total of 1,914 breast cancer cases were diagnosed after five years of follow-up. Compared with women who did not spend any time in active jobs, women who spent a high proportion (>75%) of their working years in active jobs had a borderline reduced risk of breast cancer (HR = 0.75; 95% CI = 0.56-1.00) after adjusting for breast cancer risk factors. This association was independent of leisure-time physical activity. Conclusions: These results suggest that occupational physical activity may reduce the risk of breast cancer in women.
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
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    ABSTRACT: Background and Objective Cotinine is considered a “gold standard” biomarker for smoking. However, some researchers propose alternative biomarkers, such as 2,5-dimethylfuran (2DF), and others question the value of measuring biomarkers at all. We evaluated the impact of combining self-reported smoking and each of two smoking biomarkers on smoking prevalence and the estimated association between smoking and wheezing. Methods We analyzed data from 2,228 National Health and Nutrition Survey (2005-2006) participants with self-reported current smoking data and two serum smoking biomarkers (cotinine and 2,5-dimethylfuran). Cut-points for defining smoking were > 3.08 ng/mL for cotinine and 0.014 ng/mL for 2DF. Smoking prevalence was estimated using self-report alone and then augmented with biomarker data. We compared odds ratios for wheeze in the past year associated with each smoking measure adjusted for age, gender, and education. Results 502 (23%) participants reported being current smokers. Inclusion of self-reported nonsmokers positive for smoking by cotinine increased smoking prevalence to 29%, while consideration of 2DF increased the prevalence to 24%. In adjusted models, self-reported smokers were more likely to report wheeze than nonsmokers (OR=2.45, 95% CI=1.87-3.20). The association did not change when adding 2DF to the definition (OR=2.45, 95% CI=1.89-3.19) and was modestly attenuated when adding cotinine (OR=2.32, 95% CI=1.80-3.01). Conclusions Of the two biomarkers examined, only cotinine modified smoking prevalence and effect estimates in a model of the effects of smoking on wheeze. Variation across measures could reflect underreporting, inappropriate biomarker cut-points, or differences in biomarker sensitivity. Measurement of cotinine and sensitivity analyses to estimate misclassification bias may be most beneficial in studies of populations that tend to under-report current smoking status.
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
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    ABSTRACT: Farming and pesticide use have previously been linked to non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia (CLL) and multiple myeloma (MM). We evaluated agricultural use of specific insecticides, fungicides, and fumigants and risk of NHL and NHL-subtypes (including CLL and MM) in a U.S.-based prospective cohort of farmers and commercial pesticide applicators. A total of 523 cases occurred among 54,306 pesticide applicators from enrollment (1993–97) through December 31, 2011 in Iowa, and December 31, 2010 in North Carolina. Information on pesticide use, other agricultural exposures and other factors was obtained from questionnaires at enrollment and at follow-up approximately five years later (1999–2005). Information from questionnaires, monitoring, and the literature were used to create lifetime-days and intensity-weighted lifetime days of pesticide use, taking into account exposure-modifying factors. Poisson and polytomous models were used to calculate relative risks (RR) and 95% confidence intervals (CI) to evaluate associations between 26 pesticides and NHL and five NHL-subtypes, while adjusting for potential confounding factors. For total NHL, statistically significant positive exposure-response trends were seen with lindane and DDT. Terbufos was associated with total NHL in ever/never comparisons only. In subtype analyses, terbufos and DDT were associated with small cell lymphoma/chronic lymphocytic leukemia/marginal cell lymphoma, lindane and diazinon with follicular lymphoma, and permethrin with MM. However, tests of homogeneity did not show significant differences in exposure-response among NHL-subtypes for any pesticide. Because 26 pesticides were evaluated for their association with NHL and its subtypes, some chance finding could have occurred. Our results showed pesticides from different chemical and functional classes were associated with an excess risk of NHL and NHL subtypes, but not all members of any single class of pesticides were associated with an elevated risk of NHL or NHL subtypes. These findings are among the first to suggest links between DDT, lindane, permethrin, diazinon and terbufos with NHL subtypes.
    PLoS ONE 10/2014; 9(10). · 3.53 Impact Factor
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    ABSTRACT: Our objective was to examine whether functional polymorphisms in hemochromatosis (HFE; H63D and C282Y), transferrin (TfC2), and glutathione-s-transferase Pi1 (GSTP1; Ile105Val) genes modify any lead-ALS association. We measured blood lead using atomic absorption spectroscopy and bone lead – a biomarker of cumulative lead exposure – using K-shell-X-ray fluorescence in 100 neurologist-confirmed ALS cases and 194 controls, the latter recruited as part of two separate studies; all subjects lived in New England. Participants were considered variant carriers or wild-type for each polymorphism. To assess effect modification, we included cross-product terms between lead biomarkers and each polymorphism in separate adjusted polytomous logistic regression models. Compared with wild-type, the odds ratio (OR) per 15.6 μg/g patella lead (interquartile range; IQR) was 8.24 (95% CI 0.94–72.19) times greater among C282Y variant carriers, and 0.34 (95% CI 0.15–0.78) times smaller among H63D variant carriers. Results were weaker for tibia lead. Compared with wild-type the OR per 2 μg/dl blood lead (IQR) was 0.36 (95% CI 0.19–0.68) times smaller among H63D variant carriers, and 1.96 (95% CI 0.98–3.92) times greater among GSTP1 variant carriers. In conclusion, we found that HFE and GSTP1 genotypes modified the association between lead biomarkers and ALS. Contrasting modification by the HFE polymorphisms H63D and C282Y may suggest that the modification is not simply the result of increased iron.
    Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration 10/2014; · 2.59 Impact Factor
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    ABSTRACT: The National Institute for Environmental Health Sciences (NIEHS) is conducting an epidemiologic study (GuLF STUDY) to investigate the health of the workers and volunteers who participated from April to December of 2010 in the response and cleanup of the oil release after the Deepwater Horizon explosion in the Gulf of Mexico. The exposure assessment component of the study involves analyzing thousands of personal monitoring measurements that were collected during this effort. A substantial portion of these data has values reported by the analytic laboratories to be below the limits of detection (LOD). A simulation study was conducted to evaluate three established methods for analyzing data with censored observations to estimate the arithmetic mean (AM), geometric mean (GM), geometric standard deviation (GSD), and the 95th percentile (X0.95) of the exposure distribution: the maximum likelihood (ML) estimation, the β-substitution, and the Kaplan-Meier (K-M) methods. Each method was challenged with computer-generated exposure datasets drawn from lognormal and mixed lognormal distributions with sample sizes (N) varying from 5 to 100, GSDs ranging from 2 to 5, and censoring levels ranging from 10 to 90%, with single and multiple LODs. Using relative bias and relative root mean squared error (rMSE) as the evaluation metrics, the β-substitution method generally performed as well or better than the ML and K-M methods in most simulated lognormal and mixed lognormal distribution conditions. The ML method was suitable for large sample sizes (N ≥ 30) up to 80% censoring for lognormal distributions with small variability (GSD = 2-3). The K-M method generally provided accurate estimates of the AM when the censoring was <50% for lognormal and mixed distributions. The accuracy and precision of all methods decreased under high variability (GSD = 4 and 5) and small to moderate sample sizes (N < 20) but the β-substitution was still the best of the three methods. When using the ML method, practitioners are cautioned to be aware of different ways of estimating the AM as they could lead to biased interpretation. A limitation of the β-substitution method is the absence of a confidence interval for the estimate. More research is needed to develop methods that could improve the estimation accuracy for small sample sizes and high percent censored data and also provide uncertainty intervals.
    Annals of Occupational Hygiene 09/2014; · 2.07 Impact Factor
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    ABSTRACT: Rationale: Limited prior data suggests an association between traffic-related air pollution and incident asthma in adults. No published studies assess the effect of long-term exposures to particulate matter less than 2.5 µm in diameter (PM2.5) on adult incident asthma. Objectives: To estimate the association between ambient air pollution exposures (PM2.5 and nitrogen dioxide, NO2) and development of asthma and incident respiratory symptoms. Methods: The Sister Study is a US cohort study of risk factors for breast cancer and other health outcomes (n=50,884) in sisters of women with breast cancer (enrollment: 2003-2009). Annual average (2006) ambient PM2.5 and NO2 concentrations were estimated at participants' addresses using a national land-use/kriging model incorporating roadway information. Outcomes at follow-up (2008-2012) included incident self-reported wheeze, chronic cough, and doctor-diagnosed asthma in women without baseline symptoms. Measures and Main Results: Adjusted analyses included 254 incident cases of asthma, 1,023 of wheeze, and 1,559 of chronic cough. For an interquartile range (IQR) difference (3.6 µg/m3) in estimated PM2.5 exposure, the adjusted odds-ratio (aOR) was 1.20 (95% CI=0.99-1.46, P=0.063) for incident asthma and 1.14 (95% CI=1.04-1.26, P=0.008) for incident wheeze. For NO2, there was evidence for an association with incident wheeze (aOR=1.08, 95% CI=1.00-1.17, P=0.048 per IQR of 5.8 ppb). Neither pollutant was significantly associated with incident cough (PM2.5: aOR=0.95, 95% CI=0.88-1.03, P=0.194, NO2: aOR=1.00, 95% CI=0.93-1.07, P=0.939). Conclusions: Results suggest that PM2.5 exposure increases the risk of developing asthma and PM2.5 and NO2 increase the risk of developing wheeze, the cardinal symptom of asthma, in adult women.
    American Journal of Respiratory and Critical Care Medicine 08/2014; · 11.04 Impact Factor
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    ABSTRACT: Background:Autoantibodies are of growing interest in cancer research as potential biomarkers; yet the determinants of autoimmunity are not well understood. Antinuclear antibodies (ANA) are common in the general population, and are more prevalent in women and older adults. Here we examined the relationship of ANA with reproductive and hormonal factors in a representative sample of U.S. women. Methods:We analyzed data on reproductive history and exogenous hormone use in relation to serum ANA in 2,037 females ages 12 and older from the National Health and Nutrition Examination Survey (NHANES; 1999-2004). Estimated ANA prevalences were adjusted for sampling weights. Prevalence odds ratios (POR) and 95% confidence intervals (CI) were adjusted for age, race and poverty-income-ratio, and models were stratified by menopause status. Results:In premenopausal women ages 20 and older, ANA prevalence was associated with parity (p<0.001; parous versus nulliparous POR=2.0; 95%CI 1.2, 3.4), but in parous women ANA did not vary by number of births, age at first birth, years since last birth or breastfeeding. In postmenopausal women, ANA prevalence was associated with an older age at menarche (p=0.019; age 16-20 versus 10-12 years POR=3.0, 95%CI 1.6, 5.9), but not with parity. Oral contraceptives and estrogen therapy were not associated with a higher ANA prevalence. Conclusions:Childbearing (having had one or more births) may explain age-associated elevations in ANA prevalence seen in premenopausal women. Impact:These findings highlight the importance of considering reproductive history in studies of autoimmunity and cancer in women.
    Cancer Epidemiology Biomarkers & Prevention 08/2014; 23(11). · 4.32 Impact Factor
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    ABSTRACT: This paper develops a hierarchical framework for identifying spatiotemporal patterns in data with a high degree of censoring using the gradient process. To do this, we impute censored values using a sampling-based inverse CDF method within our Markov chain Monte Carlo algorithm, thereby avoiding burdensome integration and facilitating efficient estimation of other model parameters. We illustrate use of our methodology using a simulated data example, and uncover the danger of simply substituting a space- and time-constant function of the level of detection for all missing values. We then fit our model to area measurement data of volatile organic compounds (VOC) air concentrations collected on vessels supporting the response and clean-up efforts of the Deepwater Horizon oil release that occurred starting April 20, 2010. These data contained a high percentage of observations below the detectable limits of the measuring instrument. Despite this, we were still able to make some interesting discoveries, including elevated levels of VOC near the site of the oil well on June 26th. Using the results from this preliminary analysis, we hope to inform future research on the Deepwater Horizon study, including the use of gradient methods for assigning workers to exposure categories.
    Spatial Statistics. 08/2014;
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    ABSTRACT: Farmers may be at increased risk for adverse respiratory outcomes compared with the general population due to their regular exposures to dusts, animals and chemicals. However, early life farm exposures to microbial agents may result in reduced risk. Understanding respiratory disease risk among farmers and identifying differences between farmers and other populations may lead to better understanding of the contribution of environmental exposures to respiratory disease risk in the general population.
    Occupational and Environmental Medicine 07/2014; 71(7):484-91. · 3.23 Impact Factor
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    ABSTRACT: Pesticide exposure may be positively associated with depression. Few previous studies considered the episodic nature of depression or examined individual pesticides.
    Environmental Health Perspectives 06/2014; · 7.03 Impact Factor
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    ABSTRACT: In the 2010 Deepwater Horizon Oil Spill, thousands of workers may have been exposed to various potentially harmful chemicals found in crude oil including benzene, ethylbenzene, xylene, and toluene. These and total hydrocarbons (THC) (a composite of all the volatile chemicals in crude oil) were monitored. Over 150 000 personal measurements were taken, but many of the measurements of individual chemicals were below the analytic method's limit of detection (LOD), making estimation of exposure levels challenging. The concentration of each chemical relative to THC is related to the concentration of the chemical and THC in the source crude oil. Knowing these relationships, we can develop models to predict concentrations of individual chemicals from THC concentrations when only a THC concentration was detectable. The goal of this study was to determine the correlations between concentrations of the various oil chemicals and THC for use in situations where only THC was above the LOD.
    Occupational and Environmental Medicine 06/2014; 71 Suppl 1:A102-3. · 3.23 Impact Factor
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    ABSTRACT: After the Deepwater Horizon, response vessels were brought near the wellhead area to stop the leak, collect oil and drill the relief wells. The objective of this paper is to characterise inhalation exposure on these vessels for various exposure groups (EGs) to total hydrocarbons (THCs).
    Occupational and Environmental Medicine 06/2014; 71 Suppl 1:A105. · 3.23 Impact Factor
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    ABSTRACT: BP contractors collected nearly 25 000 personal passive dosimeter samples (about 150 000 individual exposure measurements, primarily benzene, ethylbenzene, toluene, xylene and total hydrocarbon (THC)), related to the response and cleanup of the Deepwater Horizon oil spill. BP used a sampling strategy based on compliance with applicable occupational exposure limits (OELs). Most of the measurements were below the reported limit of detection (censored). This occurred because the analytic laboratories calibrated their instruments relative to the chemicals' OELs and they reported measurements below the lowest calibration standard (approximately 5% of the OEL) as less than the LOD. In an epidemiology study, however, all exposure levels are of interest rather than only those levels related to an OEL. Published evaluation studies on the analytical methods indicate that the methods were capable of measuring much lower concentrations than those reported. This presentation discusses the process used to recalculate the measurement data to the analytic method's LOD.
    Occupational and Environmental Medicine 06/2014; 71 Suppl 1:A103-4. · 3.23 Impact Factor
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    ABSTRACT: Workers and communities impacted by previous oil spills have shown increases in adverse mental health outcomes. The GuLF STUDY is investigating potential health effects among workers involved in the Deepwater Horizon oil spill clean-up response. Participants confronted physical and psychosocial stressors including exposures to oil and dispersants, income uncertainties, and challenges of family and community disruption.
    Occupational and Environmental Medicine 06/2014; 71 Suppl 1:A29. · 3.23 Impact Factor
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    ABSTRACT: Epidemiologic studies have linked pesticide use to various health outcomes, including cancer, but underlying mechanisms remain unclear. In a previous analysis from the Agricultural Health Study (AHS), a prospective cohort study of pesticide applicators in the US, use of certain pesticides was linked to shorter relative telomere length (RTL) measured in buccal cell DNA. In this analysis we examined the associations between occupational pesticide use and RTL measured in blood DNA.
    Occupational and Environmental Medicine 06/2014; 71 Suppl 1:A14-5. · 3.23 Impact Factor
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    ABSTRACT: Organic solvents are ubiquitous in occupational settings where they may contribute to risks for carcinogenesis. However, there is limited information on organic solvents as human breast carcinogens. We examined the relationship between occupational exposure to solvents and breast cancer in a prospective study of 47,661 women with an occupational history in the Sister Study cohort. Occupational solvent exposure was categorized using self-reported job-specific solvent use collected at baseline. Multivariable Cox regression analyses were used to assess breast cancer risk, adjusting for established breast cancer risk factors. A total of 1,798 women were diagnosed with breast cancer during follow-up, including 1,255 invasive cases. Overall the risk of invasive breast cancer was not associated with lifetime exposure to solvents [HR, 1.04; 95% confidence interval (CI), 0.88-1.24]. Parous women who worked with solvents before their first full-term birth had an increased risk of estrogen receptor-positive invasive breast cancer compared with women who never worked with solvents (HR, 1.39; 95% CI, 1.03-1.86). A significantly elevated risk for estrogen receptor-positive invasive breast cancer was associated with solvent exposure among clinical laboratory technologists and technicians (HR, 2.00; 95% CI, 1.07-3.73). Occupational exposure to solvents before first birth, a critical period of breast tissue differentiation, may result in increased vulnerability for breast cancer. Our findings suggest a need for future studies in this area to focus on exposure time windows and solvent types in different occupational settings. Cancer Res; 74(11); 3076-83. ©2014 AACR.
    Cancer Research 06/2014; 74(11):3076-3083. · 9.28 Impact Factor
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    ABSTRACT: Farming and exposure to pesticides have been linked to non-Hodgkin lymphoma (NHL), and multiple myeloma (MM) in previous studies. We evaluated use of insecticides, fungicides and fumigants and risk of NHL, including MM and other NHL sub-types in the Agricultural Health Study, a US-based prospective cohort study.
    Occupational and Environmental Medicine 06/2014; 71 Suppl 1:A36. · 3.23 Impact Factor

Publication Stats

7k Citations
1,524.41 Total Impact Points


  • 2014
    • University of Bergen
      Bergen, Hordaland, Norway
  • 2002–2014
    • National Institutes of Health
      • • Branch of Epidemiology (EPI)
      • • Branch of Occupational and Environmental Epidemiology
      Maryland, United States
  • 1988–2014
    • University of North Carolina at Chapel Hill
      • • Department of Epidemiology
      • • Department of Obstetrics and Gynecology
      • • School of Nursing
      • • Department of Pediatrics
      North Carolina, United States
  • 1983–2014
    • National Institute of Environmental Health Sciences
      • • Epidemiology Branch
      • • Biostatistics Branch
      Durham, North Carolina, United States
  • 2013
    • Centers for Disease Control and Prevention
      • Division of Respiratory Disease Studies
      Atlanta, Michigan, United States
    • Northwestern University
      • Department of Preventive Medicine
      Evanston, IL, United States
    • Georgia Regents University
      Augusta, Georgia, United States
  • 2008–2013
    • Karolinska Institutet
      • Institutionen för medicinsk epidemiologi och biostatistik
      Solna, Stockholm, Sweden
  • 2012
    • Parkinson’s Institute
      Sunnyvale, California, United States
    • Georgia Health Sciences University
      Augusta, Georgia, United States
  • 2011
    • Brigham Young University - Provo Main Campus
      • Department of Health Science
      Provo, UT, United States
  • 2006–2011
    • University of Iowa
      • • Department of Occupational and Environmental Health
      • • Department of Epidemiology
      Iowa City, IA, United States
  • 2010
    • University of Washington Seattle
      • Department of Pediatrics
      Seattle, WA, United States
    • University of Nevada, Reno
      Reno, Nevada, United States
    • The Nebraska Medical Center
      Omaha, Nebraska, United States
    • Wake Forest School of Medicine
      • Center for Genomics and Personalized Medicine Research
      Winston-Salem, NC, United States
  • 1996–2010
    • National Cancer Institute (USA)
      • • Division of Cancer Epidemiology and Genetics
      • • Occupational and Environmental Epidemiology
      • • Epidemiology and Biostatistics
      Bethesda, MD, United States
  • 2009
    • United States Environmental Protection Agency
      Cincinnati, Ohio, United States
    • Seoul National University
      • Department of Preventive Medicine
      Sŏul, Seoul, South Korea
  • 2005–2008
    • Fred Hutchinson Cancer Research Center
      • Division of Public Health Sciences
      Seattle, WA, United States
  • 2007
    • University of New Mexico
      Albuquerque, New Mexico, United States
    • Korea University
      • College of Medicine
      Seoul, Seoul, South Korea
  • 2005–2006
    • University of Ottawa
      • Department of Epidemiology and Community Medicine
      Ottawa, Ontario, Canada
  • 2004–2005
    • University of Illinois at Chicago
      • Division of Epidemiology and Biostatistics
      Chicago, IL, United States
  • 2000
    • Temple University
      Philadelphia, Pennsylvania, United States
  • 1999
    • University of Minnesota Twin Cities
      • Department of Pediatrics
      Minneapolis, MN, United States
    • Yale-New Haven Hospital
      New Haven, Connecticut, United States