This study was carried out to examine the association between exposure to polycyclic aromatic hydrocarbon with traffic exhaust and biomarkers of lipid peroxidation and antioxidant levels among highway toll station workers. We conducted a cross-sectional study of 47 female highway toll station workers exposed to traffic exhausts and 27 female classroom trainees as a reference group. Exposure assessment was based on a biomarker of polycyclic aromatic hydrocarbon exposure, urinary 1-hydroxypyrene-glucuronide (1-OHPG). Urinary isoprostane was assayed as a biomarker of lipid peroxidation, and plasma antioxidative capacity of lipid-soluble substances (ACL) and water-soluble substances (ACW) was measured. The median concentration of urinary isoprostane was higher among the exposed non-smokers (4.63 ng/mL) compared with the reference non-smokers (3.52 ng/mL, difference: 0.91, 95% CI -0.15 to 1.98) (Wilcoxon rank-sum test: p = 0.04). The median concentration of ACW among non-smoking exposed subjects (37.9 μg/mL Trolox equivalent) was lower than that of the reference non-smokers (86.3 μg/mL). Adjusting for confounding effects by linear regression, a change in log (isoprostane) concentration was significantly related to a unit change in log(1-OHPG) (regression coefficient [s], β = 0.14, 95% CI 0.07 to 0.21). Exposure to polycyclic aromatic hydrocarbon is associated with increased lipid peroxidation and reduced antioxidative capacity in toll station workers.

Environmental exposures often produce reactive electrophiles in vivo, leading to oxidative stress, which plays a major role in carcinogenesis. These electrophiles frequently form adducts with human albumin, which can be measured to assess in vivo oxidative stress. Here, we aimed to examine the associations between circulatory albumin adducts and acute myeloid leukemia (AML), the most common adult myeloid leukemia that showed consistent associations with environmental exposures. We conducted a nested case-control study of 52 incident AML cases and 103 controls matched on age, sex and race within two prospective cohorts: the CLUE and PLCO studies. We measured 42 untargeted albumin adducts in prediagnostic samples using liquid chromatography-high-resolution mass spectrometry. Circulatory albumin adducts were associated with AML in conditional logistic regression models. For instance, higher levels of Cys34 disulfide adduct of the S-γ-glutamylcysteine, a precursor of the essential antioxidant, glutathione were associated with a lower risk of AML (odds ratios [95% confidence intervals]) for the 1st, 2nd and 3rd tertiles were 1.0, 0.65 (0.31-1.36) and 0.31 (0.12-0.80), respectively (P-trend = .01). These associations were largely driven by effects present among cases diagnosed at or above the median follow-up time of 5.5 years. In conclusion, applying a novel approach to characterize exposures in the prediagnostic samples, we found evidence supporting the notion that oxidative stress may play a role in the pathogenesis of AML. Our findings offer insight into AML etiology and may be relevant in identifying novel therapeutic targets.

Background: A common pathway where carcinogenic chemicals exert their biological influence is the generation of oxidative stress resulting from the production of reactive electrophiles. These electrophiles often form adducts with nucleophilic Cys34 of human serum albumin, which can be quantified to assess in vivo oxidative stress and other biological processes. Here, we aimed to examine the associations of Cys34 albumin adducts with acute myeloid leukemia (AML), the most common adult myeloid leukemia, which has strong links with exposure to certain chemicals and ionizing radiation. Methods: This nested case-control study included data from 52 incident AML cases and 103 controls matched on age, sex, and race from two prospective cohorts: the CLUE study (24 cases and 48 controls) and the PLCO Trial (28 cases and 55 controls) and 42 untargeted serum Cys34 albumin adducts measured by liquid chromatography-high resolution mass spectrometry. We calculated odds ratios (OR) and 95% confidence intervals (CI) for AML risk for each albumin adduct on a continuous scale and across tertiles of exposure in combined samples as well as stratified by the median years of follow-up. Results: The median (range) follow-up from phlebotomy at enrollment was 5.47 (1.02 - 29.93) years. Several Cys34 albumin adducts were significantly associated with incident AML risk. For example, higher serum levels of S-γ-Glu-Cys adduct (894.44) were associated with lower risk of AML (ORcontinuous= 0.18; 95% CI: 0.37-0.92; p-value= 0.04). Similarly, the ORs for the 2nd and 3rd tertiles of adduct levels compared to the lowest tertile were 0.65 (95% CI: 0.31-1.36) and 0.31 (95% CI: 0.12-0.80), respectively (p-trend = 0.01). Stratification by median years of follow-up showed that the association was largely driven by effects present among cases diagnosed ≥5.47 years of follow-up; the ORcontinuous was 0.06 (95% CI: 0.01-0.61; p-value = 0.02) and ORs by tertile were 0.32 (95% CI: 0.09-1.16) and 0.22 (95% CI: 0.06-0.89) for the 2nd and 3rd tertiles, respectively compared to the lowest tertile (p-trend= 0.04). In contrast, there was no association for cases diagnosed within 5.47 years of follow-up (ORcontinuous= 0.78; 95% CI: 0.07-8.95; p-value= 0.84). Conclusion: Higher serum levels of Cys34 adduct of S-γ-Glu-Cys, which is a substrate for the biosynthesis of L-glutathione, a key antioxidant in humans, were associated with a lower risk of AML. Modified Cys34 adducts of human serum albumin could potentially help to understand the underlying mechanisms of leukemogenesis. Citation Format: Mohammad L. Rahman, Bryan Bassig, Hasmik Grigoryan, Wei Hu, Dean Hosgood, Wen-Yi Huang, Jason Wong, Paul Strickland, Stephen Rappaport, Qing Lan, Nathaniel Rothman. A nested case-control study of untargeted serum protein adductomics and the risk of AML [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 225.

Islami, Farhad; Boffetta, Paolo; van Schooten, Frederik J; Strickland, Paul; Phillips, David H; Pourshams, Akram; Fazel-Tabar Malekshah, Akbar; Godschalk, Roger; Jafari, Elham; Etemadi, Arash; +6 more... Abubaker, Salahadin; Kamangar, Farin; Straif, Kurt; Møller, Henrik; Schüz, Joachim; Malekzadeh, Reza; (2012) Exposure to Polycyclic Aromatic Hydrocarbons Among Never Smokers in Golestan Province, Iran, an Area of High Incidence of Esophageal Cancer a Cross-Sectional Study with Repeated Measurement of Urinary 1-OHPG in Two Seasons. Front Oncol, 2. 14-. ISSN 2234943X DOI: https://doi.org/10.3389/fonc.2012.00014 Downloaded from: http://researchonline.lshtm.ac.uk/id/eprint/56926/

Abstract Purpose of study: Female breast cancer is the second leading cause of cancer death in U.S. women, and the incidence of new breast cancer cases continues to increase. Despite slightly lower breast cancer incidence rates among African American (AA) compared to European American (EA) women in the U.S., AA women experience significantly higher breast cancer mortality. To better understand the extent to which environmental and genetic factors might help explain higher mortality rates among AA women, we examined the association between a measure of exposure to chemical pollutants and genomic profiling with breast cancer mortality among women with breast cancer in North Carolina. Procedures: Using a molecular epidemiologic approach, we examined the association of county hog concentration (a marker of environmental exposure to chemical pollutants) and genomic variations identified via targeted exome sequencing with age-adjusted breast cancer mortality rates among 146 women in North Carolina, stratified by race (AA vs. EA). The odds of breast cancer-specific mortality were estimated as a function of county hog concentration quintiles. Results: Overall, breast cancer mortality among AA women was higher than among EA women (OR=1.4, p<0.0001). Although there was no effect of hog concentration on breast cancer mortality of EA women, there was an increase in deaths from breast cancer in African American women in the highest quintile of hog concentration (OR=1.18, p=0.03), compared to the lower quintiles. In the lowest quintile of hog concentration, breast cancer mortality remained higher among AA versus EA women (OR=1.38, p=0.0002). This suggests that along with environmental factors, biological factors also contribute to disparities. Next, we performed targeted exome sequencing of breast cancer samples collected from a cohort in eastern North Carolina. AA breast cancer samples showed a high frequency of CNVs (copy number variations) of COL11A2, COL12A1, CYP21A2, LYRM2, COL9A1, DNAH11, and DST. EA breast cancer samples showed a high frequency of CNVs of PRG4, PLB1, CHRM5, OCA2, HMCN1, and MUC5B. Among these, HMCN1, MUC5B (among EA), and COL12A1, DNAH11, DST (among AA) were genes with significantly high CNVs identified from The Cancer Genome Atlas. Conclusions: Our findings suggest that living in a county with a high concentration of hogs may increase breast cancer mortality risk among AA women, and the high frequency of CNVs varies by race; both CNV and county hog concentration may contribute to racial disparities in breast cancer mortality among AA and EA women in North Carolina. Citation Format: Jung S. Byun, Sean Lee, Sijung Yun, Eliseo J. Perez-Stable, Anna M. Napoles, Paul Strickland, Kevin L. Gardner. Race, copy number variation, and local hog concentration in breast cancer mortality [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1183.

Elevated serum sCD27 and sCD30 from a single banked sample have been associated with future non-Hodgkin lymphoma risk (NHL); however, the etiologic relevance of this finding is unclear. To address this question, we conducted a case-control study (235 cases, 235 controls) nested within the CLUE-I and CLUE-II cohorts, which enrolled participants in 1974 and 1989 respectively in Washington County, Maryland. Our study features a subset of 102 cases and 102 controls with two banked pre-diagnostic samples each, collected 15 years apart. In analyses involving an individual sample per subject, both sCD27 and sCD30 were associated with NHL diagnosed up to 20 years later. In analyses involving repeated samples, cases were significantly more likely than controls to have higher analyte levels in the CLUE-II vs. CLUE-I sample for sCD27 (p = 0.006) but not sCD30 (p = 0.16). In joint analyses of dichotomized analyte levels in both samples, the strongest NHL association observed for sCD27 was for having below-median levels in CLUE-I and above-median levels in CLUE-II [odds ratio (OR) 3.6, 95% confidence interval (CI) 1.4-9.2 vs. below-median levels in both). In joint analyses for sCD30, the strongest NHL association was observed for having above-median levels in both samples (OR 1.7, 95% CI 0.8-3.7), particularly for cases diagnosed >10 years after the CLUE-II sample (OR 2.4, 95% CI 0.9-6.7). Our findings suggest that sCD27 is a disease marker for NHL and add to the weight of evidence that elevated circulating sCD30 is a marker of increased NHL susceptibility.

Background Most smoke-free legislation to reduce secondhand smoke (SHS) exposure exempts waterpipe (hookah) smoking venues. Few studies have examined SHS exposure in waterpipe venues and their employees. Methods We surveyed 276 employees of 46 waterpipe tobacco venues in Istanbul, Moscow, and Cairo. We interviewed venue managers and employees and collected biological samples from employees to measure exhaled carbon monoxide (CO), hair nicotine, saliva cotinine, urine cotinine, urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and urine 1-hydroxypyrene glucuronide (1-OHPG). We estimated adjusted geometric mean ratios (GMR) of each SHS biomarker by employee characteristics and indoor air SHS measures. Results There were 73 nonsmoking employees and 203 current smokers of cigarettes or waterpipe. In nonsmokers, the median (interquartile) range concentrations of SHS biomarkers were 1.1 (0.2, 40.9) µg/g creatinine urine cotinine, 5.5 (2, 15) ng/mL saliva cotinine, 0.95 (0.36, 5.02) ng/mg hair nicotine, 1.48 (0.98, 3.97) pg/mg creatinine urine NNAL, 0.54 (0.25, 0.97) pmol/mg creatinine urine 1-OHPG, and 1.67 (1.33, 2.33) ppm exhaled CO. An 8-hour increase in work hours was associated with higher urine cotinine (GMR: 1.68, 95% CI: 1.20, 2.37) and hair nicotine (GMR: 1.22, 95% CI: 1.05, 1.43). Lighting waterpipes was associated with higher saliva cotinine (GMR: 2.83, 95% CI: 1.05, 7.62). Conclusions Nonsmoking employees of waterpipe tobacco venues were exposed to high levels of SHS, including measurable levels of carcinogenic biomarkers (tobacco-specific nitrosamines and PAHs). Implications Smoke-free regulation should be extended to waterpipe venues to protect nonsmoking employees and patrons from the adverse health effects of SHS.

BACKGROUND: Advancements in the quality and availability of highly sensitive analytical instrumentation and methodologies have led to increased interest in the use of microsamples. Among microsamples, dried blood spots (DBS) are the most well-known. Although there have been a variety of review papers published on DBS, there has been no attempt at describing the full range of analytes measurable in DBS, or any systematic approach published for characterizing the strengths and weaknesses associated with adoption of DBS analyses. CONTENT: A scoping review of reviews methodology was used for characterizing the state of the science in DBS. We identified 2018 analytes measured in DBS and found every common analytic method applied to traditional liquid samples had been applied to DBS samples. Analytes covered a broad range of biomarkers that included genes, transcripts, proteins, and metabolites. Strengths of DBS enable its application in most clinical and laboratory settings, and the removal of phlebotomy and the need for refrigeration have expanded biosampling to hard-to-reach and vulnerable populations. Weaknesses may limit adoption in the near term because DBS is a nontraditional sample often requiring conversion of measurements to plasma or serum values. Opportunities presented by novel methodologies may obviate many of the current limitations, but threats around the ethical use of residual samples must be considered by potential adopters. SUMMARY: DBS provide a wide range of potential applications that extend beyond the reach of traditional samples. Current limitations are serious but not intractable. Technological advancements will likely continue to minimize constraints around DBS adoption. (c) 2017 American Association for Clinical Chemistry

Abstract Elevated serum levels of the immune activation markers sCD27 and sCD30 have been consistently associated with increased future risk of non-Hodgkin lymphoma (NHL). However, past studies could not clarify patterns of these markers over time preceding diagnosis, given their use of a single banked sample per participant. To address this question, we conducted a nested case-control study within the CLUE-I and CLUE-II cohorts including 102 case-control matched pairs with two banked samples per participant, collected fifteen years apart. The CLUE-II sCD27 concentrations among cases were higher than in the earlier CLUE-I samples (P<0.0001), whereas no systematic difference was observed for controls (P=0.89). The sCD27 increase was greater for cases diagnosed less than 10 years vs. 10+ years after CLUE-II enrollment (P = 0.0007). For sCD30, an increase between samples was observed for both cases (P = 0.0002) and controls (P=0.02), and the magnitude of increase among cases did not significantly differ across the two follow-up periods (P = 0.12). In comparison to having low (below-median) sCD27 levels in both CLUE-I and CLUE-II samples, associations with NHL were observed for having low CLUE-I sCD27 and high CLUE-II sCD27 (“low / high”; odds ratio 2.4, 95% confidence interval 1.0-6.2) as well as having high sCD27 levels in both samples (“high / high”; 2.1, 1.0-4.4). For sCD30, only the “high-high” category was associated with NHL (2.1, 0.9-5.0). The “low-high” sCD27 association was apparent only for cases diagnosed less than 10 years after CLUE-II (4.1, 1.3-13.0), while the “high-high” associations were consistent across follow-up periods. Our findings suggest that multiple factors may underlie NHL associations with these markers; rising sCD27 closer to diagnosis is likely driven by occult disease, whereas associations with stable elevated analyte levels may reflect etiologically relevant effects. Citation Format: Mark P. Purdue, Qing Lan, Judith Hoffman-Bolton, Allan Hildesheim, Paul Strickland, Kala Visvanathan, Nathaniel Rothman. Circulating sCD27 and sCD30 in samples collected fifteen years apart and non-Hodgkin lymphoma risk: Findings from the CLUE-I and CLUE-II cohorts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3232.

Polycyclic aromatic hydrocarbons (PAHs), the by-products of incomplete combustion of organic materials, are commonly found on particulate matter (PM) and have been associated with the development of asthma and asthma exacerbation in urban populations. We examined time spent in the home and outdoors as predictors of exposures to airborne PAHs and measured urinary 1-hydroxypyrene-glucuronide (1-OHPG) as internal dose of PAHs in 118 children aged 5–12 years from Baltimore, MD. During weeklong periods (Saturday–Saturday) in each of four seasons: daily activities were assessed using questionnaires, indoor air nicotine and PM concentrations were monitored, and urine specimens were collected on Tuesday (day 3) and Saturday (day 7) for measurement of 1-OHPG. Time spent in non-smoking homes was associated with significantly decreased 1-OHPG concentration in urine (β=−0.045, 95% CI (−0.076, −0.013)), and secondhand smoke (SHS) exposures modified these associations, with higher urinary 1-OHPG concentrations in children spending time in smoking homes than non-smoking homes (P-value for interaction=0.012). Time spent outdoors was associated with increased urinary 1-OHPG concentrations (β=0.097, 95% CI (0.037, 0.157)) in boys only. Our results suggest that SHS and ambient (outdoor) air pollution contribute to internal dose of PAHs in inner city children.

Section 1: Foundations and Principles 1. Gastronomy and Tourism through the Media Lens 2. A History of Gastronomy 3. Food, Destinations and Tourists 4. Festivals and Gastronomy 5. Food Rituals and Etiquette Section 2: Trends and Innovations 6. The Quest for Good Food 7. Food Gardens and Foraging 8. Farmers' Markets 9. Food for Nutrition 10. Food Trucks and Pop-Up Restaurants Section 3: Media and Gastronomy 11. Food Pioneers and Champions 12. A Recipe for Travel 13. Just Desserts: A Darker Cinema Gastronomica 14. The Picnic: Gastronomy Al Fresco 15. Gastronomic Globalization

OBJECTIVE:The prevalence of waterpipe tobacco smoking has risen in recent decades. Controlled studies suggest that waterpipe secondhand smoke (SHS) contains similar or greater quantities of toxicants than cigarette SHS, which causes significant morbidity and mortality. Few studies have examined SHS from waterpipe tobacco in real-world settings. The purpose of this study was to quantify SHS exposure levels and describe the characteristics of waterpipe tobacco venues.METHODS:In 2012-2014, we conducted cross-sectional surveys of 46 waterpipe tobacco venues (9 in Istanbul, 17 in Moscow, and 20 in Cairo). We administered venue questionnaires, conducted venue observations, and sampled indoor air particulate matter (PM2.5) (N=35), carbon monoxide (CO) (N=23), particle-bound polycyclic aromatic hydrocarbons (p-PAHs) (N=31), 4-methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) (N=43), and air nicotine (N=46).RESULTS:Venue characteristics and SHS concentrations were highly variable within and between cities. Overall, we observed a mean (standard deviation (SD)) of 5 (5) waterpipe smokers and 5 (3) cigarette smokers per venue. The overall median (25th percentile, 75th percentile) of venue mean air concentrations was 136 (82, 213) µg/m(3) for PM2.5, 3.9 (1.7, 22) ppm for CO, 68 (33, 121) ng/m(3) for p-PAHs, 1.0 (0.5, 1.9) ng/m(3) for NNK, and 5.3 (0.7, 14) µg/m(3) for nicotine. PM2.5, CO, and p-PAHs concentrations were generally higher in venues with more waterpipe smokers and cigarette smokers, although associations were not statistically significant.CONCLUSION:High concentrations of SHS constituents known to cause health effects indicate that indoor air quality in waterpipe tobacco venues may adversely affect the health of employees and customers.

Asthma is the most common chronic illness in children living in developed countries and the leading cause of childhood hospitalization and school absenteeism. Prevalence rates of asthma are increasing and show disparities across gender, geographic regions, and ethnic/racial groups. Common risk factors for developing childhood asthma include exposure to tobacco smoke, previous allergic reactions, a family history of asthma, allergic rhinitis or eczema, living in an urban environment, obesity and lack of physical exercise, severe lower respiratory tract infections, and male gender. Asthma exacerbation in children can be triggered by a variety of factors, including allergens (e.g., pollen, dust mites, and animal dander), viral and bacterial infections, exercise, and exposure to airway irritants. Recent studies have shown that exposure to polycyclic aromatic hydrocarbons (PAHs), a major component of fine particulate matter from combustion sources, is also associated with onset of asthma, and increasing asthmatic symptoms. In this paper, we review sources of childhood PAH exposure and the association between airborne PAH exposure and childhood asthma prevalence and exacerbation.

This poster reports on an Australian Government Office for Learning and Teaching (OLT) project to assist business educators to embed simulations into the curriculum. The purpose of this project was to gather and disseminate good practice in the design of pedagogy and assessment in simulation-based units in business. Data collection included interviews with educators and decision makers, student focus groups and surveys. The project included the development of an online toolkit consisting of case studies, a good practice guide and a simulation learning barometer. A ‘framework for simulation-based pedagogy’ is presented as a key outcome of the project.

There is an emerging hypothesis that exposure to cadmium (Cd), mercury (Hg), lead (Pb), and selenium (Se) in utero and early childhood could have long-term health consequences. However, there are sparse data on early life exposures to these elements in US populations, particularly in urban minority samples. This study measured levels of Cd, Hg, Pb, and Se in 50 paired maternal, umbilical cord, and postnatal blood samples from the Boston Birth Cohort (BBC). Maternal exposure to Cd, Hg, Pb, and Se was 100% detectable in red blood cells (RBCs), and there was a high degree of maternal–fetal transfer of Hg, Pb, and Se. In particular, we found that Hg levels in cord RBCs were 1.5 times higher than those found in the mothers. This study also investigated changes in concentrations of Cd, Hg, Pb, and Se during the first few years of life. We found decreased levels of Hg and Se but elevated Pb levels in early childhood. Finally, this study investigated the association between metal burden and preterm birth and low birthweight. We found significantly higher levels of Hg in maternal and cord plasma and RBCs in preterm or low birthweight births, compared with term or normal birthweight births. In conclusion, this study showed that maternal exposure to these elements was widespread in the BBC, and maternal–fetal transfer was a major source of early life exposure to Hg, Pb, and Se. Our results also suggest that RBCs are better than plasma at reflecting the trans-placental transfer of Hg, Pb, and Se from the mother to the fetus. Our study findings remain to be confirmed in larger studies, and the implications for early screening and interventions of preconception and pregnant mothers and newborns warrant further investigation.

Despite the successes of smoke-free legislation, tobacco control policies largely exempt water pipe venues. Compared to cigarettes, experimental studies suggest that water pipe secondhand smoke contains higher levels of nicotine, carbon monoxide (CO), and polycyclic aromatic hydrocarbons (PAHs). Our objective was to characterize airborne concentrations of secondhand smoke contaminants in water pipe venues and biomarkers of exposure in employees. In 2012-2013, we conducted cross-sectional surveys of water pipe venues and employees in Istanbul, Turkey and Moscow, Russia. Data from Cairo, Egypt is expected in March 2014. We enrolled 9 venues (71 employees) in Turkey and 17 venues (104 employees) in Russia. We collected air samples of nicotine, particulate matter (PM2.5), nicotine-derived nitrosamine ketone (NNK), CO, and particle-bound PAHs. Employee exposure was assessed via biomarkers in urine (cotinine, NNAL [a NNK metabolite], 1-hydroxypyrene glucuronide [1-OHPG; a PAH metabolite]), hair (nicotine), saliva (cotinine), and exhaled breath (CO). Fieldworkers recorded venue characteristics, customer smoking behaviors, and employee sociodemographic and smoking status. The median (25th, 75th percentile) concentrations of PM2.5 were 207 (66, 424) µg/m3 and 214 (110, 500) µg/m3 in Turkey and Russia, respectively. Biomarkers of exposure to tobacco smoking and secondhand smoke were extremely high among smokers and were elevated among non-smokers (Table 1). This study provides novel, real-world evidence for the inclusion of water pipe venues in smoke-free legislation.

Context: Cholinesterase (ChE) specific activity is the ratio of ChE activity to ChE mass and, as a biomarker of exposure to cholinesterase inhibitors, has a potential advantage over simple ChE activity. Objective: To examine the association of several potential correlates (serum arylesterase/paraoxonase activity, serum albumin, sex, age, month of blood collection, and smoking) with plasma ChE specific activity. Methods: We analyzed data from 195 cancer-free controls from a nested case-control study, accounting for potential confounding. Results: Arylesterase activity had an independent, statistically significant positive association with ChE specific activity, and its magnitude was the greatest for the arylesterase phenotype corresponding to the QQ PON1192 genotype followed by phenotypes corresponding to QR and RR genotypes. Serum albumin was positively associated with ChE specific activity. Conclusions: Plasma arylesterase activity was positively associated with plasma ChE specific activity. This observation is consistent with protection conferred by a metabolic phenotype resulting in reduced internal dose.

PURPOSE:Polycyclic aromatic hydrocarbons (PAHs) are byproducts of incomplete combustion of organic materials. Sources include tobacco smoke, charbroiled meat, and air pollution. Indirect evidence suggests that PAHs may be associated with carcinogenesis, but the association with gastric cancer is unclear.METHODS:Using a nested case-control study design, we examined prediagnostic urinary concentrations of 1-hydroxypyrene glucuronide (1-OHPG), a PAH metabolite, in 153 gastric cancer cases and 306 matched controls within the Shanghai Women's Health Study. Conditional logistic regression adjusted for potential risk factors was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs).RESULTS:Urinary 1-OHPG concentrations were slightly higher among cases than controls, with medians of 0.29 μmol/mol Cr (interquartile range, 0.16-0.48) and 0.24 μmol/mol Cr (interquartile range, 0.12-0.45), respectively. Increasing concentrations of 1-OHPG appeared to be associated with elevated risk of gastric cancer, but not within the highest category of 1-OHPG (Q4 vs Q1: OR = 1.4; 95% CI = 0.8-2.5).CONCLUSIONS:Our findings suggest that higher concentrations of 1-OHPG are related to gastric cancer risk, but no clear dose-response relationship was observed.