@article{rosen_kotlarz_knappe_lea_collier_richardson_hoppin_2024, title={Erratum: “Drinking Water–Associated PFAS and Fluoroethers and Lipid Outcomes in the GenX Exposure Study”}, url={https://doi.org/10.1289/EHP13342}, DOI={10.1289/EHP13342}, abstractNote={,}, journal={Environmental Health Perspectives}, author={Rosen, Emma M. and Kotlarz, Nadine and Knappe, Detlef R.U. and Lea, C. Suzanne and Collier, David N. and Richardson, David B. and Hoppin, Jane A.}, year={2024}, month={Feb} }
 @article{kotlarz_mccord_collier_lea_strynar_lindstrom_wilkie_islam_matney_tarte_et al._2024, title={Erratum: “Measurement of Novel, Drinking Water-Associated PFAS in Blood from Adults and Children in Wilmington, North Carolina”}, url={https://doi.org/10.1289/EHP13341}, DOI={10.1289/EHP13341}, journal={Environmental Health Perspectives}, author={Kotlarz, Nadine and McCord, James and Collier, David and Lea, C. Suzanne and Strynar, Mark and Lindstrom, Andrew B. and Wilkie, Adrien A. and Islam, Jessica Y. and Matney, Katelyn and Tarte, Phillip and et al.}, year={2024}, month={Feb} }
 @article{holcomb_christensen_hoffman_lee_blackwood_clerkin_gallard-góngora_harris_kotlarz_mitasova_et al._2024, title={Estimating Rates of Change to Interpret Quantitative Wastewater Surveillance of Disease Trends}, url={https://doi.org/10.1101/2024.04.24.24306320}, DOI={10.1101/2024.04.24.24306320}, abstractNote={Abstract Background Wastewater monitoring data can be used to estimate disease trends to inform public health responses. One commonly estimated metric is the rate of change in pathogen quantity, which typically correlates with clinical surveillance in retrospective analyses. However, the accuracy of rate of change estimation approaches has not previously been evaluated. Objectives We assessed the performance of approaches for estimating rates of change in wastewater pathogen loads by generating synthetic wastewater time series data for which rates of change were known. Each approach was also evaluated on real-world data. Methods Smooth trends and their first derivatives were jointly sampled from Gaussian processes (GP) and independent errors were added to generate synthetic viral load measurements; the range hyperparameter and error variance were varied to produce nine simulation scenarios representing different potential disease patterns. The directions and magnitudes of the rate of change estimates from four estimation approaches (two established and two developed in this work) were compared to the GP first derivative to evaluate classification and quantitative accuracy. Each approach was also implemented for public SARS-CoV-2 wastewater monitoring data collected January 2021 – May 2024 at 25 sites in North Carolina, USA. Results All four approaches inconsistently identified the correct direction of the trend given by the sign of the GP first derivative. Across all nine simulated disease patterns, between a quarter and a half of all estimates indicated the wrong trend direction, regardless of estimation approach. The proportion of trends classified as plateaus (statistically indistinguishable from zero) for the North Carolina SARS-CoV-2 data varied considerably by estimation method but not by site. Discussion Our results suggest that wastewater measurements alone might not provide sufficient data to reliably track disease trends in real-time. Instead, wastewater viral loads could be combined with additional public health surveillance data to improve predictions of other outcomes.}, author={Holcomb, David A. and Christensen, Ariel and Hoffman, Kelly and Lee, Allison and Blackwood, A. Denene and Clerkin, Thomas and Gallard-Góngora, Javier and Harris, Angela and Kotlarz, Nadine and Mitasova, Helena and et al.}, year={2024}, month={Apr} }
 @article{holcomb_christensen_hoffman_lee_blackwood_clerkin_gallard-gongora_harris_kotlarz_mitasova_et al._2024, title={Estimating rates of change to interpret quantitative wastewater surveillance of disease trends}, volume={951}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2024.175687}, abstractNote={Wastewater monitoring data can be used to estimate disease trends to inform public health responses. One commonly estimated metric is the rate of change in pathogen quantity, which typically correlates with clinical surveillance in retrospective analyses. However, the accuracy of rate of change estimation approaches has not previously been evaluated.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Holcomb, David A. and Christensen, Ariel and Hoffman, Kelly and Lee, Allison and Blackwood, A. Denene and Clerkin, Thomas and Gallard-Gongora, Javier and Harris, Angela and Kotlarz, Nadine and Mitasova, Helena and et al.}, year={2024}, month={Nov} }
 @article{kotlarz_mccord_wiecha_weed_cuffney_enders_strynar_knappe_reich_hoppin_2024, title={Measurement of Hydro-EVE and 6:2 FTS in Blood from Wilmington, North Carolina, Residents, 2017-2018}, volume={132}, ISSN={["1552-9924"]}, url={https://doi.org/10.1289/EHP14503}, DOI={10.1289/EHP14503}, number={2}, journal={ENVIRONMENTAL HEALTH PERSPECTIVES}, author={Kotlarz, Nadine and McCord, James and Wiecha, Nate and Weed, Rebecca A. and Cuffney, Michael and Enders, Jeffrey R. and Strynar, Mark and Knappe, Detlef R. U. and Reich, Brian J. and Hoppin, Jane A.}, year={2024}, month={Feb} }
 @article{kotlarz_mccord_wiecha_weed_cuffney_enders_strynar_knappe_reich_hoppin_2024, title={Reanalysis of PFO5DoA Levels in Blood from Wilmington, North Carolina, Residents, 2017-2018}, volume={132}, ISSN={["1552-9924"]}, url={https://doi.org/10.1289/EHP13339}, DOI={10.1289/EHP13339}, abstractNote={,}, number={2}, journal={ENVIRONMENTAL HEALTH PERSPECTIVES}, author={Kotlarz, Nadine and McCord, James and Wiecha, Nate and Weed, Rebecca A. and Cuffney, Michael and Enders, Jeffrey R. and Strynar, Mark and Knappe, Detlef R. U. and Reich, Brian J. and Hoppin, Jane A.}, year={2024}, month={Feb} }
 @article{wallis_kotlarz_knappe_collier_lea_reif_mccord_strynar_dewitt_hoppin_2023, title={Estimation of the Half-Lives of Recently Detected Per- and Polyfluorinated Alkyl Ethers in an Exposed Community}, volume={57}, ISSN={["1520-5851"]}, url={https://doi.org/10.1021/acs.est.2c08241}, DOI={10.1021/acs.est.2c08241}, abstractNote={To estimate half-lives for novel fluoroethers, the GenX Exposure Study obtained two serum measurements for per- and polyfluoroalkyl substances (PFAS) for 44 participants of age 12-86 years from North Carolina, collected 5 and 11 months after fluoroether discharges into the drinking water source were controlled. The estimated half-lives for these compounds were 127 days (95% confidence interval (95% CI) = 86, 243 days) for perfluorotetraoxadecanoic acid (PFO4DA), 296 days for Nafion byproduct 2 (95% CI = 176, 924 days), and 379 days (95% CI = 199, 3870 days) for perfluoro-3,5,7,9,11-pentaoxadodecanoic acid (PFO5DoA). Using these estimates and the literature values, a model was built that predicted PFAS half-lives using structural properties. Three chemical properties predicted 55% of the variance of PFAS half-lives based on 15 PFAS. A model with only molecular weight predicted 69% of the variance. Some properties can predict the half-lives of PFAS, but a deeper understanding is needed. These fluoroethers had biological half-lives longer than published half-lives for PFHxA and PFHpA (30-60 days) but shorter than those for PFOA and PFOS (800-1200 days). These are the first and possibly only estimates of human elimination half-lives of these fluoroethers.}, number={41}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Wallis, Dylan J. and Kotlarz, Nadine and Knappe, Detlef R. U. and Collier, David N. and Lea, C. Suzanne and Reif, David and McCord, James and Strynar, Mark and DeWitt, Jamie C. and Hoppin, Jane A.}, year={2023}, month={Oct}, pages={15348–15355} }
 @article{cuffney_wilkie_kotlarz_knappe_lea_collier_dewitt_hoppin_2023, title={Factors associated with per- and polyfluoroalkyl substances (PFAS) serum concentrations in residents of New Hanover County, North Carolina: The GenX exposure study}, volume={237}, ISSN={["1096-0953"]}, url={https://doi.org/10.1016/j.envres.2023.117020}, DOI={10.1016/j.envres.2023.117020}, abstractNote={In 2017, people living in New Hanover County, North Carolina, learned that for ∼40 years they were unknowingly exposed to per- and polyfluoroalkyl substances (PFAS) through drinking water sourced by the Cape Fear River. Using data from the GenX Exposure Study, which measured serum PFAS levels in county residents, we aimed to understand questionnaire-measured factors associated with serum PFAS levels. Because most residents were served by the same municipal water source, we focused on surrogate factors of drinking water exposure that may contribute to variability in PFAS levels. Our analysis included 335 participants aged 6 and older. We included seven chemicals detected in ≥75% of the study population: four well-studied perfluoroalkyl acids (PFOA, PFOS, PFNA, PFHxS) and three understudied fluoroethers (Nafion byproduct 2, PFO4DA, PFO5DoA). For each PFAS, we evaluated associations of variables with serum PFAS levels adjusting for key demographic characteristics. Additionally, we developed predictive models for each PFAS. We used years of residence in the lower Cape Fear Region as a surrogate for water consumption. Duration of drinking water exposure was associated with higher serum levels of all seven PFAS. Drinking municipal water treated by home filters or other sources of water (non-city) were associated with lower PFAS concentrations for all seven PFAS compared to drinking municipal water without additional filtration. Males had higher levels of well-studied PFAS, but there was no difference for fluoroethers. For six PFAS, the predictive models explained ≥30% of the variance in serum PFAS levels. While some factors were significantly associated with levels of individual PFAS, their relative importance to overall prediction was low, such as microwave popcorn consumption. Consistently, water consumption-related variables were important for both the association and predictive investigations. These analyses provide additional evidence that drinking water is a primary source for serum PFAS concentrations among New Hanover County residents.}, journal={ENVIRONMENTAL RESEARCH}, author={Cuffney, Michael and Wilkie, Adrien A. and Kotlarz, Nadine and Knappe, Detlef and Lea, C. Suzanne and Collier, David N. and Dewitt, Jamie and Hoppin, Jane A.}, year={2023}, month={Nov} }
 @article{hoffman_holcomb_reckling_clerkin_blackwood_beattie_reyes_harris_mitasova_kotlarz_et al._2023, title={Using Detrending to Assess SARS-CoV-2 Wastewater Loads as a Leading Indicator of Fluctuations in COVID-19 Cases at Fine Temporal Scales: Correlations Across Twenty Sewersheds in North Carolina}, url={https://doi.org/10.31223/X5967X}, DOI={10.31223/X5967X}, abstractNote={Wastewater surveillance emerged during the COVID-19 pandemic as a novel strategy for tracking the burden of illness in communities. Previous work has shown that trends in wastewater SARS-CoV-2 viral loads correlate well with reported COVID-19 case trends over longer time periods (i.e., months). We used detrending time series to reveal shorter sub-trend patterns (i.e., weeks) to identify leads or lags in the temporal alignment of the wastewater/case relationship. Daily incident COVID-19 cases and twice-weekly wastewater SARS-CoV-2 viral loads measured at 20 North Carolina sewersheds in 2021 were detrended using smoothing ranges of ∞, 16, 8, 4 and 2 weeks, to produce detrended cases and wastewater viral loads at progressively finer time scales. For each sewershed and smoothing range, we calculated the Spearman correlation between the cases and the wastewater viral loads with offsets of -7 to +7 days. We identified a conclusive lead/lag relationship at 15 of 20 sewersheds, with detrended wastewater loads temporally leading detrended COVID-19 cases at 11 of these sites. For the 11 leading sites, the correlation between wastewater loads and cases was greatest for wastewater loads sampled at a median lead time of 6 days before the cases were reported. Distinct lead/lag relationships were the most pronounced after detrending with smoothing ranges of 4–8 weeks, suggesting that SARS-CoV-2 wastewater viral loads can track fluctuations in COVID-19 case incidence rates at fine time scales and may serve as a leading indicator in many settings. These results could help public health officials identify, and deploy timely responses in, areas where cases are increasing faster than the overall pandemic trend.}, author={Hoffman, Kelly and Holcomb, David and Reckling, Stacie and Clerkin, Thomas and Blackwood, Denene and Beattie, Rachelle and Reyes, Francis and Harris, Angela and Mitasova, Helena and Kotlarz, Nadine and et al.}, year={2023}, month={Jun} }
 @article{hoffman_holcomb_reckling_clerkin_blackwood_beattie_reyes_harris_mitasova_kotlarz_et al._2023, title={Using detrending to assess SARS-CoV-2 wastewater loads as a leading indicator of fluctuations in COVID-19 cases at fine temporal scales: Correlations across twenty sewersheds in North Carolina}, url={https://doi.org/10.1371/journal.pwat.0000140}, DOI={10.1371/journal.pwat.0000140}, abstractNote={Wastewater surveillance emerged during the COVID-19 pandemic as a novel strategy for tracking the burden of illness in communities. Previous work has shown that trends in wastewater SARS-CoV-2 viral loads correlate well with reported COVID-19 case trends over longer time periods (i.e., months). We used detrending time series to reveal shorter sub-trend patterns (i.e., weeks) to identify leads or lags in the temporal alignment of the wastewater/case relationship. Daily incident COVID-19 cases and twice-weekly wastewater SARS-CoV-2 viral loads measured at 20 North Carolina sewersheds in 2021 were detrended using smoothing ranges of ∞, 16, 8, 4 and 2 weeks, to produce detrended cases and wastewater viral loads at progressively finer time scales. For each sewershed and smoothing range, we calculated the Spearman correlation between the cases and the wastewater viral loads with offsets of -7 to +7 days. We identified a conclusive lead/lag relationship at 15 of 20 sewersheds, with detrended wastewater loads temporally leading detrended COVID-19 cases at 11 of these sites. For the 11 leading sites, the correlation between wastewater loads and cases was greatest for wastewater loads sampled at a median lead time of 6 days before the cases were reported. Distinct lead/lag relationships were the most pronounced after detrending with smoothing ranges of 4–8 weeks, suggesting that SARS-CoV-2 wastewater viral loads can track fluctuations in COVID-19 case incidence rates at fine time scales and may serve as a leading indicator in many settings. These results could help public health officials identify, and deploy timely responses in, areas where cases are increasing faster than the overall pandemic trend.}, journal={PLOS Water}, author={Hoffman, Kelly and Holcomb, David and Reckling, Stacie and Clerkin, Thomas and Blackwood, Denene and Beattie, Rachelle and Reyes, Francis and Harris, Angela and Mitasova, Helena and Kotlarz, Nadine and et al.}, editor={Kapoor, VikramEditor}, year={2023}, month={Oct} }
 @article{al-faliti_kotlarz_mccall_harris_smith_stadler_reyes_vela_2022, title={Comparing Rates of Change in SARS-CoV-2 Wastewater Load and Clinical Cases in 19 Sewersheds Across Four Major Metropolitan Areas in the United States}, volume={7}, url={https://doi.org/10.1021/acsestwater.2c00106}, DOI={10.1021/acsestwater.2c00106}, abstractNote={There is no standard approach to interoperate the during the pandemic. We tested several data processing approaches on wastewater surveillance data sets generated from 19 sewersheds across four major metropolitan areas in the United States from May 2020 through October 2021. First, we explored the effect of different data processing techniques on the correlation between SARS-CoV-2 wastewater RNA load and clinical case counts and found that locally weighted smoothing (LOESS) smoothing applied to multivariate imputation by chain equations (MICE)-imputed wastewater viral load led to the strongest correlations in 16 out of 19 sewersheds (84%). Next, we calculated the rate of change (RC) in wastewater viral load and in clinical cases and found that imputing missing viral load data on a 28-day window produced the strongest correlation (Spearman's rho = 0.63). Furthermore, we determined an average sensitivity threshold of 2.4 new COVID-19 cases per day resulted in a significant RC in wastewater, but sensitivity varied with the laboratory method used. Our retrospective analysis using RC highlighted certain methodological insights, reduced site-specific impacts, and estimated a wastewater sensitivity threshold-supporting the use of relative, rather than absolute, measures of SARS-CoV-2 wastewater data for more interoperable data sets.}, journal={ACS ES&T Water}, publisher={American Chemical Society (ACS)}, author={Al-Faliti, Mitham and Kotlarz, Nadine and McCall, Camille and Harris, Angela R. and Smith, Adam L. and Stadler, Lauren B. and Reyes, III and Vela, Jeseth Delgado}, year={2022}, month={Nov} }
 @article{rosen_kotlarz_knappe_lea_collier_richardson_hoppin_2022, title={Drinking Water-Associated PFAS and Fluoroethers and Lipid Outcomes in the GenX Exposure Study}, volume={130}, ISSN={["1552-9924"]}, url={https://doi.org/10.1289/EHP11033}, DOI={10.1289/EHP11033}, abstractNote={Background: Residents of Wilmington, North, Carolina, were exposed to drinking water contaminated by fluoroethers and legacy per- and polyfluoroalkyl substances (PFAS), such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), with fluoroether exposure occurring from 1980 to 2017. PFOA and PFOS have previously been associated with metabolic dysfunction; however, few prior studies have examined associations between other PFAS and lipid levels. Objectives: We measured the association between serum fluoroether and legacy PFAS levels and various cholesterol outcomes. Methods: Participants in the GenX Exposure Study contributed nonfasting blood samples in November 2017 and May 2018 that were analyzed for 20 PFAS (10 legacy, 10 fluoroethers) and serum lipids [total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides] and calculated non-HDL cholesterol. We estimated covariate-adjusted associations between quartiles of exposure to each of the PFAS measures (as well as the summed concentrations of legacy PFAS, fluoroethers, and all 10 targeted PFAS) and lipid outcomes by fitting inverse probability of treatment weighted linear regressions. Results: In this cross-sectional study of 326 participants (age range 6–86 y), eight PFAS were detected in >50% of the population. For PFOS and perfluorononanoic acid (PFNA), non-HDL cholesterol was approximately 5mg/dL higher per exposure quartile increase: [PFOS: 4.89; 95% confidence interval (CI): 0.10, 9.68 and PFNA: 5.25 (95% CI: 0.39, 10.1)], whereas total cholesterol was approximately 6mg/dL higher per quartile [PFOS: 5.71 (95% CI: 0.38, 11.0), PFNA: 5.92 (95% CI: 0.19, 11.7)]. In age-stratified analyses, associations were strongest among the oldest participants. One fluoroether was associated with higher HDL, whereas other fluoroether compounds were not associated with serum lipid levels. Discussion: PFNA and PFOS were associated with higher levels of total and non-HDL cholesterol, with associations larger in magnitude among older adults. In the presence of these legacy PFAS, fluoroethers appeared to be associated with HDL but not non-HDL lipid measures. https://doi.org/10.1289/EHP11033}, number={9}, journal={ENVIRONMENTAL HEALTH PERSPECTIVES}, author={Rosen, Emma M. and Kotlarz, Nadine and Knappe, Detlef R. U. and Lea, C. Suzanne and Collier, David N. and Richardson, David B. and Hoppin, Jane A.}, year={2022}, month={Sep} }
 @article{wallis_barton_knappe_kotlarz_mcdonough_higgins_hoppin_adgate_2023, title={Source apportionment of serum PFASs in two highly exposed communities}, volume={855}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2022.158842}, abstractNote={Per- and polyfluoroalkyl substances (PFASs) are synthetic chemicals that are ubiquitous in environmental and biological systems, including human serum. PFASs are used in many products and industrial processes and are tied to numerous health effects. Due to multiple sources and exposure pathways, methods are needed to identify PFAS sources in communities to develop targeted interventions. We assessed effectiveness of three source apportionment methods (UNMIX, positive matrix factorization [PMF], and principal component analysis - multiple linear regression [PCA-MLR]) for identifying contributors to human serum PFAS concentrations in two highly exposed populations in Colorado and North Carolina where drinking water was contaminated via upstream sources, including a Space Force base and a fluorochemical manufacturing plant. UNMIX and PMF models extracted three to four potential PFAS exposure sources in the Colorado and North Carolina cohorts while PCA-MLR classified two in each cohort. No sources were characterized in NHANES (National Health and Nutrition Examination Study). Results suggest that these three methods can successfully identify sources in highly exposed populations. Future PFAS exposure research should focus on analyzing serum for an expanded PFAS panel, identifying cohorts with other distinct point source exposures, and combining biological and environmental data to better understand source apportionment results in the context of PFAS toxicokinetic behavior.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Wallis, Dylan J. and Barton, Kelsey E. and Knappe, Detlef R. U. and Kotlarz, Nadine and McDonough, Carrie A. and Higgins, Christopher P. and Hoppin, Jane A. and Adgate, John L.}, year={2023}, month={Jan} }
 @article{kotlarz_holcomb_pasha_reckling_kays_lai_daly_palani_bailey_guidry_et al._2023, title={Timing and Trends for Municipal Wastewater, Lab-Confirmed Case , and Syndromic Case Surveillance of COVID-19 in Raleigh, North Carolina}, volume={113}, ISSN={["1541-0048"]}, url={https://publons.com/wos-op/publon/54927766/}, DOI={10.2105/AJPH.2022.307108}, abstractNote={ Objectives. To compare 4 COVID-19 surveillance metrics in a major metropolitan area.  Methods. We analyzed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in wastewater influent and primary solids in Raleigh, North Carolina, from April 10 through December 13, 2020. We compared wastewater results with lab-confirmed COVID-19 cases and syndromic COVID-like illness (CLI) cases to answer 3 questions: (1) Did they correlate? (2) What was the temporal alignment of the different surveillance systems? (3) Did periods of significant change (i.e., trends) align?  Results. In the Raleigh sewershed, wastewater influent, wastewater primary solids, lab-confirmed cases, and CLI were strongly or moderately correlated. Trends in lab-confirmed cases and wastewater influent were observed earlier, followed by CLI and, lastly, wastewater primary solids. All 4 metrics showed sustained increases in COVID-19 in June, July, and November 2020 and sustained decreases in August and September 2020.  Conclusions. In a major metropolitan area in 2020, the timing of and trends in municipal wastewater, lab-confirmed case, and syndromic case surveillance of COVID-19 were in general agreement.  Public Health Implications. Our results provide evidence for investment in SARS-CoV-2 wastewater and CLI surveillance to complement information provided through lab-confirmed cases. (Am J Public Health. 2023;113(1):79–88. https://doi.org/10.2105/AJPH.2022.307108 ) }, number={1}, journal={AMERICAN JOURNAL OF PUBLIC HEALTH}, publisher={American Public Health Association}, author={Kotlarz, Nadine and Holcomb, David A. and Pasha, Tanvir and Reckling, Stacie and Kays, Judith and Lai, Yi-Chun and Daly, Sean and Palani, Sivaranjani and Bailey, Erika and Guidry, Virginia T. and et al.}, year={2023}, month={Jan}, pages={79–88} }
 @article{guillette_mccord_guillette_polera_rachels_morgeson_kotlarz_knappe_reading_strynar_et al._2020, title={Elevated levels of per- and polyfluoroalkyl substances in Cape Fear River Striped Bass (Morone saxatilis) are associated with biomarkers of altered immune and liver function}, volume={136}, ISSN={["1873-6750"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85079172705&partnerID=MN8TOARS}, DOI={10.1016/j.envint.2019.105358}, abstractNote={Per- and polyfluoroalkyl substances (PFAS) are anthropogenic chemicals of concern that persist in the environment. Environmental monitoring revealed high concentrations of hexafluoropropylene oxide dimer acid (HFPO-DA) and other novel PFAS in the lower Cape Fear River; however, there is limited information on PFAS exposures and effects of this contamination on aquatic biota. Serum concentrations of 23 PFAS in Striped Bass (Morone saxatilis) from the Cape Fear River (n = 58) and a reference population from an aquaculture laboratory on the Pamlico/Tar watershed (n = 29) were quantified using liquid chromatography and high-resolution mass spectrometry, and correlations between PFAS concentrations and health-related serum biomarkers were evaluated. Perfluorooctane sulfonate, the predominant PFAS in Cape Fear River Striped Bass serum, was detectable in every sample with serum concentrations reaching 977 ng/mL. Perfluorononanoic and perfluorodecanoic acid were also detected in all samples, with perfluorohexanesulfonic acid present in >98% of the samples. HFPO-DA (range <0.24-5.85 ng/mL) and Nafion byproduct 2 (range <0.2-1.03 ng/mL) were detected in 48% and 78% of samples, respectively. The mean total PFAS concentration found in domestic Striped Bass raised in well-water under controlled aquaculture conditions was 40 times lower, with HPFO-DA detected in 10% of the samples, and Nafion byproduct 2 was not detected. The elevated PFAS concentrations found in the Cape Fear River Striped Bass were associated with biomarkers of alterations in the liver and immune system.}, journal={ENVIRONMENT INTERNATIONAL}, author={Guillette, T. C. and McCord, James and Guillette, Matthew and Polera, M. E. and Rachels, Kyle T. and Morgeson, Clint and Kotlarz, Nadine and Knappe, Detlef R. U. and Reading, Benjamin J. and Strynar, Mark and et al.}, year={2020}, month={Mar} }
 @article{haig_kotlarz_kalikin_chen_guikema_lipuma_raskin_2020, title={Emerging investigator series: bacterial opportunistic pathogen gene markers in municipal drinking water are associated with distribution system and household plumbing characteristics}, volume={6}, ISSN={["2053-1419"]}, DOI={10.1039/d0ew00723d}, abstractNote={Municipally-treated drinking water (DW) is a potential source of exposure to bacterial opportunistic pathogens (OPs), which can cause infection in susceptible individuals.}, number={11}, journal={ENVIRONMENTAL SCIENCE-WATER RESEARCH & TECHNOLOGY}, author={Haig, Sarah-Jane and Kotlarz, Nadine and Kalikin, Linda M. and Chen, Thomas and Guikema, Seth and LiPuma, John J. and Raskin, Lutgarde}, year={2020}, month={Nov}, pages={3032–3043} }
 @article{kotlarz_mccord_collier_lea_strynar_lindstrom_wilkie_islam_matney_tarte_et al._2020, title={Measurement of Novel, Drinking Water-Associated PFAS in Blood from Adults and Children in Wilmington, North Carolina}, volume={128}, ISSN={["1552-9924"]}, DOI={10.1289/EHP6837}, abstractNote={Background: From 1980 to 2017, a fluorochemical manufacturing facility discharged wastewater containing poorly understood per- and polyfluoroalkyl substances (PFAS) to the Cape Fear River, the primary drinking water source for Wilmington, North Carolina, residents. Those PFAS included several fluoroethers including HFPO-DA also known as GenX. Little is known about the bioaccumulation potential of these fluoroethers. Objective: We determined levels of fluoroethers and legacy PFAS in serum samples from Wilmington residents. Methods: In November 2017 and May 2018, we enrolled 344 Wilmington residents ≥6 years of age into the GenX Exposure Study and collected blood samples. Repeated blood samples were collected from 44 participants 6 months after enrollment. We analyzed serum for 10 fluoroethers and 10 legacy PFAS using liquid chromatography–high-resolution mass spectrometry. Results: Participants’ ages ranged from 6 to 86 y, and they lived in the lower Cape Fear Region for 20 y on average (standard deviation: 16 y). Six fluoroethers were detected in serum; Nafion by-product 2 and PFO4DA were detected in >99% of participants. PFO3OA and NVHOS were infrequently detected. Hydro-EVE was present in a subset of samples, but we could not quantify it. GenX was not detected above our analytical method reporting limit (2 ng/mL). In participants with repeated samples, the median decrease in fluoroether levels ranged from 34% for Nafion byproduct 2 to 65% for PFO4DA in 6 months due to wastewater discharge control. Four legacy PFAS (PFHxS, PFOA, PFOS, PFNA) were detected in most (≥97%) participants; these levels were higher than U.S. national levels for the 2015–2016 National Health and Nutrition Examination Survey. The sum concentration of fluoroethers contributed 23% to participants’ summed PFAS (median: 25.0 ng/mL). Conclusion: Poorly understood fluoroethers released into the Cape Fear River by a fluorochemical manufacturing facility were detected in blood samples from Wilmington, North Carolina, residents. Health implications of exposure to these novel PFAS have not been well characterized. https://doi.org/10.1289/EHP6837}, number={7}, journal={ENVIRONMENTAL HEALTH PERSPECTIVES}, author={Kotlarz, Nadine and McCord, James and Collier, David and Lea, C. Suzanne and Strynar, Mark and Lindstrom, Andrew B. and Wilkie, Adrien A. and Islam, Jessica Y. and Matney, Katelyn and Tarte, Phillip and et al.}, year={2020}, month={Jul} }
 @article{kotlarz_raskin_zimbric_errickson_lipuma_caverly_2019, title={Retrospective Analysis of Nontuberculous Mycobacterial Infection and Monochloramine Disinfection of Municipal Drinking Water in Michigan}, volume={4}, ISSN={["2379-5042"]}, url={https://doi.org/10.1128/mSphere.00160-19}, DOI={10.1128/mSphere.00160-19}, abstractNote={Infections by nontuberculous mycobacteria (NTM) result in significant morbidity, mortality, and health care costs. NTM are primarily acquired from environmental sources, including exposure to municipally treated drinking water. Higher levels of NTM have been reported in drinking water disinfected with monochloramine than in drinking water disinfected with chlorine. Our results suggest that municipal drinking water disinfection with monochloramine compared to chlorine is not associated with higher risk of NTM infection. This is important given that regulations that limit drinking water concentrations of disinfection by-products, which are formed primarily when chlorine disinfection is used, incentivize drinking water utilities to change from chlorine disinfection to monochloramine disinfection.}, number={4}, journal={MSPHERE}, author={Kotlarz, Nadine and Raskin, Lutgarde and Zimbric, Madsen and Errickson, Josh and LiPuma, John J. and Caverly, Lindsay J.}, editor={Mattes, Timothy E.Editor}, year={2019} }
 @article{haig_kotlarz_lipuma_raskin_2018, title={A High-Throughput Approach for Identification of Nontuberculous Mycobacteria in Drinking Water Reveals Relationship between Water Age and Mycobacterium avium}, volume={9}, ISSN={["2150-7511"]}, DOI={10.1128/mbio.02354-17}, abstractNote={ABSTRACT
          
            Nontuberculous mycobacteria (NTM) frequently detected in drinking water (DW) include species associated with human infections, as well as species rarely linked to disease. Methods for improved the recovery of NTM DNA and high-throughput identification of NTM are needed for risk assessment of NTM infection through DW exposure. In this study, different methods of recovering bacterial DNA from DW were compared, revealing that a phenol-chloroform DNA extraction method yielded two to four times as much total DNA and eight times as much NTM DNA as two commercial DNA extraction kits. This method, combined with high-throughput, single-molecule real-time sequencing of NTM
            rpoB
            genes, allowed the identification of NTM to the species, subspecies, and (in some cases) strain levels. This approach was applied to DW samples collected from 15 households serviced by a chloraminated distribution system, with homes located in areas representing short (<24 h) and long (>24 h) distribution system residence times. Multivariate statistical analysis revealed that greater water age (i.e., combined distribution system residence time and home plumbing stagnation time) was associated with a greater relative abundance of
            Mycobacterium avium
            subsp.
            avium
            , one of the most prevalent NTM causing infections in humans. DW from homes closer to the treatment plant (with a shorter water age) contained more diverse NTM species, including
            Mycobacterium abscessus
            and
            Mycobacterium chelonae
            . Overall, our approach allows NTM identification to the species and subspecies levels and can be used in future studies to assess the risk of waterborne infection by providing insight into the similarity between environmental and infection-associated NTM.
          
          
            IMPORTANCE
            An extraction method for improved recovery of DNA from nontuberculous mycobacteria (NTM), combined with single-molecule real-time sequencing (PacBio) of NTM
            rpoB
            genes, was used for high-throughput characterization of NTM species and in some cases strains in drinking water (DW). The extraction procedure recovered, on average, eight times as much NTM DNA and three times as much total DNA from DW as two widely used commercial DNA extraction kits. The combined DNA extraction and sequencing approach allowed high-throughput screening of DW samples to identify NTM, revealing that the relative abundance of
            Mycobacterium avium
            subsp.
            avium
            increased with water age. Furthermore, the two-step barcoding approach developed as part of the PacBio sequencing method makes this procedure highly adaptable, allowing it to be used for other target genes and species.
          }, number={1}, journal={MBIO}, author={Haig, Sarah-Jane and Kotlarz, Nadine and LiPuma, John J. and Raskin, Lutgarde}, year={2018} }
 @article{kotlarz_rockey_olson_haig_sanford_lipuma_raskin_2018, title={Biofilms in Full-Scale Drinking Water Ozone Contactors Contribute Viable Bacteria to Ozonated Water}, volume={52}, ISSN={["1520-5851"]}, url={https://doi.org/10.1021/acs.est.7b04212}, DOI={10.1021/acs.est.7b04212}, abstractNote={Concentrations of viable microbial cells were monitored using culture-based and culture-independent methods across multichamber ozone contactors in a full-scale drinking water treatment plant. Membrane-intact and culturable cell concentrations in ozone contactor effluents ranged from 1200 to 3750 cells/mL and from 200 to 3850 colony forming units/mL, respectively. Viable cell concentrations decreased significantly in the first ozone contact chamber, but rose, even as ozone exposure increased, in subsequent chambers. Our results implicate microbial detachment from biofilms on contactor surfaces, and from biomass present within lime softening sediments in a hydraulic dead zone, as a possible reason for increasing cell concentrations in water samples from sequential ozone chambers. Biofilm community structures on baffle walls upstream and downstream from the dead zone were significantly different from each other ( p = 0.017). The biofilms downstream of the dead zone contained a significantly ( p = 0.036) higher relative abundance of bacteria of the genera Mycobacterium and Legionella than the upstream biofilms. These results have important implications as the effluent from ozone contactors is often treated further in biologically active filters and bacteria in ozonated water continuously seed filter microbial communities.}, number={5}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Kotlarz, Nadine and Rockey, Nicole and Olson, Terese M. and Haig, Sarah-Jane and Sanford, Larry and LiPuma, John J. and Raskin, Lutgarde}, year={2018}, month={Mar}, pages={2618–2628} }