Lung Cancer and Radon: Pooled Analysis of Uranium Miners Hired in 1960 or Later.

BACKGROUND: Despite reductions in exposure for workers and the general public, radon remains a leading cause of lung cancer. Prior studies of underground miners depended heavily upon information on deaths among miners employed in the early years of mine operations when exposures were high and tended to be poorly estimated. OBJECTIVES: To strengthen the basis for radiation protection, we report on the follow-up of workers employed in the later periods of mine operations for whom we have more accurate exposure information and for whom exposures tended to be accrued at intensities that are more comparable to contemporary settings. METHODS: We conducted a pooled analysis of cohort studies of lung cancer mortality among 57,873 male uranium miners in Canada, Czech Republic, France, Germany, and the United States, who were first employed in 1960 or later (thereby excluding miners employed during the periods of highest exposure and focusing on miners who tend to have higher quality assessments of radon progeny exposures). We derived estimates of excess relative rate per 100 working level months (ERR/100 WLM) for mortality from lung cancer. RESULTS: The analysis included 1.9 million person-years of observation and 1,217 deaths due to lung cancer. The relative rate of lung cancer increased in a linear fashion with cumulative exposure to radon progeny (ERR/100 WLM=1.33; 95% CI: 0.89, 1.88). The association was modified by attained age, age at exposure, and annual exposure rate; for attained ages <55 y, the ERR/100 WLM was 8.38 (95% CI: 3.30, 18.99) among miners who were exposed at ≥35 years of age and at annual exposure rates of <0.5 working levels. This association decreased with older attained ages, younger ages at exposure, and higher exposure rates. DISCUSSION: Estimates of association between radon progeny exposure and lung cancer mortality among relatively contemporary miners are coherent with estimates used to inform current protection guidelines. https://doi.org/10.1289/EHP10669.

Clinical and urodynamic features of secondary tethered cord syndrome: How can they be found longitudinally?

PURPOSE: Secondary tethered cord syndrome (TCS) can be diagnosed with signs of progressive deterioration in urological or neuro-orthopedic systems following primary untethering surgery. Though urological deterioration is a common secondary TCS manifestation, a paucity of diagnostic criteria makes diagnoses challenging. A detailed description of urological deterioration may help diagnose secondary TCS. Thus, the clinical and urodynamic features of the current secondary TCS cases were described. MATERIALS AND METHODS: Fifty-one patients who had undergone reuntethering for secondary TCS experienced improvement or stabilization of progressive problems. Moreover, their clinical and videourodynamic changes were longitudinally described. RESULTS: Loss of postoperative spontaneous voiding was the first urological secondary TCS sign for those who could void spontaneously. Urological problems mostly occurred during elementary school (6-12 years). Major urological presentations were recalcitrant urinary tract infection or urinary incontinence. Follow-up videourodynamic studies revealed typical changes, from acontractile bladder to overactive and low-complaint bladders. While detrusor overactivity did not always occur during the progression, detrusor sphincter dyssynergia was always present in all patients with urological deterioration. All patients postoperatively showed significant urodynamic improvement regardless of preoperative bladder dysfunction. This included four cases of restoring spontaneous voiding. Nine patients experienced newly appearing nonprogressive neuro-orthopedic complications despite their urological improvement. CONCLUSIONS: Urological deterioration should prompt secondary TCS suspicion, and changes in clinical patterns and videourodynamic studies helped diagnose it. However, reuntethering can effectively address urological problems at the cost of some neuro-orthopedic functions in some patients.

Strengthening surveillance of consumer products in Canada: the vaping example. / Renforcer la surveillance des produits de consommation au Canada : l'exemple du vapotage.

INTRODUCTION: The overall objective of this study was to demonstrate how information collected by the Consumer Product Safety Program ("the Program") can be used to identify emerging hazards. Specifically, this study characterized and quantified trends associated with vaping reports received by the Program over the past five years. METHODS: Data collated by the Program were extracted for the period from 1 January, 2015 to 30 September, 2019. The data were summarized using descriptive statistics and trends were quantified for annual percent change. In order to compare characteristics of vaping reports, the proportionate injury ratios (PIRs) and corresponding 95% CIs were used to compare vaping-related injuries to all other reports received by the Program. RESULTS: A total of 71 vaping-related reports were received between 1 January, 2015 and 30 September, 2019. During this period, the annual percent change increase in the number of reports received was approximately 73% annually (p < .05). Among the reported injuries, 41% were burn injuries. Proportionally, there were more vaping reports involving males (PIR = 1.89; 95% CI: 1.51-2.36) and individuals between the ages of 15 and 19 years (PIR = 11.53; 95 % CI: 4.95-26.8) as compared to all other reports submitted to the Program. CONCLUSIONS: While the number of reports relating to vaping products is small, the results of this analysis suggest that certain groups, including males and youth, are more likely to be the subject of a vaping-related incident.

Injuries and poisonings associated with e-cigarettes and vaping substances, electronic Canadian Hospitals Injury Reporting and Prevention Program, 2011-2019. / Traumatismes et intoxications associés à la cigarette électronique et aux substances de vapotage, base de données électronique du Système canadien hospitalier d'information et de recherche en prévention des traumatismes, 2011-2019.

Electronic cigarettes are devices that deliver nicotine to the user by heating an e-liquid. In Canada, the Tobacco and Vaping Products Act became law on May 23, 2018. The purpose of this study was to describe the cases of injuries and poisonings associated with e-cigarette and vaping substances that presented to Canadian emergency departments within the electronic Canadian Hospitals Injury Reporting and Prevention Program network between 2011 and 2019. A total of 68 cases were retrieved (54.4% males). Of the 68 cases, 8 occurred between 2011 and 2014, while 35 (51.5%) occurred in 2018 or 2019. Ingestions, inhalations and burns were observed.

Of 68 cases of injury or poisoning due to e-cigarette use or vaping between 2011 and 2019, 54.4% involved males. Of the 68 cases, 8 occurred between 2011 and 2014 while 35 (51.5%) occurred in 2018 or 2019. The annual percent change (APC) was 50.7% (95% CI: 15.9­96.1). Children under 5 years of age who either ingested the e-juice or vaping liquid or inhaled from the device accounted for 52.9% of incidents. In two cases, the device's battery exploded in the pocket of an adult male, causing a burn to the thigh. There were 3 traumatic brain injuries as a result of a fall subsequent to vaping.

Parmi les 68 cas de traumatisme ou d'intoxication causés par l'usage de la cigarette électronique ou le vapotage entre 2011 et 2019, 54,4 % concernaient des patients de sexe masculin. Parmi les 68 cas, 8 dataient de 2011 à 2014 et 35 (51,5 %) de 2018 et 2019. La variation annuelle en pourcentage (VAP) a été de 50,7 % (IC à 95 % : 15,9 à 96,1). Des enfants de moins de 5 ans ayant ingéré ou inhalé du liquide à vapoter à même le dispositif comptent pour 52,9 % des incidents. Dans deux cas, la pile du dispositif a explosé dans la poche d'un adulte, provoquant une brûlure à la cuisse. Trois traumatismes cérébraux se sont produits en raison d'une chute survenue à la suite d'une activité de vapotage.

Tobacco smoke exposure and sleep: estimating the association of urinary cotinine with sleep quality. / Exposition à la fumée du tabac et sommeil : estimation de l'association entre concentration de cotinine urinaire et qualité du sommeil.

INTRODUCTION: A majority of studies on tobacco smoke exposure and sleep quality have relied on self-reported smoking, resulting in potential exposure misclassification and biases related to self-report. The objective of this study was to investigate associations between urinary cotinine, a biological marker of tobacco smoke exposure, and sleep quality measures, including sleep duration, sleep continuity or efficiency, sleep satisfaction and alertness during normal waking hours. METHODS: Using data on a national sample of 10 806 adults (aged 18-79 years) from the Canadian Health Measures Survey (2007-2013), we performed binary logistic regression analyses to estimate associations between urinary cotinine concentrations and sleep quality measures, while controlling for potential confounders. Additionally, we performed ordinal logistic regression to assess the association between urinary cotinine concentrations and increased number of sleep problems. RESULTS: Overall, 28.7% of adult Canadian survey respondents had urinary cotinine concentrations above the limit of detection (LOD), nd the prevalence of each sleep problem ranged from 5.5% to 35.6%. Elevated urinary cotinine concentrations (quartile 4 vs.

Histopathologic Analysis of Lung Cancer Incidence Associated with Radon Exposure among Ontario Uranium Miners.

Although radon is a well-established contributor to lung cancer mortality among uranium miners, the effects of radon decay products on different histopathologies of lung carcinoma are not well established. Using a retrospective cohort design, this study aims to examine the risks of lung cancer by histological subtypes associated with exposure to radon decay products among the Ontario Uranium Miners cohort. Cases were stratified by histological groups, and associated risks were estimated for cumulative radon exposure after adjustment for attained age and calendar period. Between 1969 and 2005, 1274 incident cases of primary lung cancer were identified. Of these, 1256 diagnoses (99%) contained information on histology. Squamous cell carcinoma was most common (31%), followed by adenocarcinoma (20%), large cells (18%), small cell lung carcinoma (14%), and other or unspecified cell types (17%). Of the histological sub-groups, small cell lung carcinoma had the strongest association with cumulative radon exposure; compared to the reference group (<1 cumulative working level months (WLM)), the highest exposure category (>60 cumulative WLM) had a relative risk (RR) of 2.76 (95% CI: 1.67⁻4.57). Adenocarcinoma had the lowest risk and was not significantly associated with exposure to radon decay products (RR = 1.49, 95% CI: 0.96⁻2.31). An increasing, linear trend in relative risk was noted with increasing cumulative WLM across small cell, squamous cell, and large cell lung carcinomas (Ptrend < 0.05). Similarly, the excess relative risk (ERR) per WLM was highest for small cell lung carcinoma (ERR/WLM = 0.15, p < 0.01), followed by squamous cell carcinoma (ERR/WLM = 0.12, p < 0.01). Non-statistically significant excess risk was observed for adenocarcinoma (ERR/WLM = 0.004, p = 0.07). Our analysis of the Ontario Uranium Miners cohort data shows differences in the magnitude of the risks across four histological subtypes of lung carcinoma; the strongest association was noted for small cell lung carcinoma, followed by squamous cell, large cell, and lastly adenocarcinoma, which showed no significant associations with exposure to radon decay products.

The lows of getting high: sentinel surveillance of injuries associated with cannabis and other substance use.

OBJECTIVES: Cannabis is a widely used illicit substance that has been associated with acute injuries. This study seeks to provide near real-time injury estimates related to cannabis and other substance use from the electronic Canadian Hospitals Injury Reporting and Prevention Program (eCHIRPP) database. METHODS: Data from the eCHIRPP database, years 2011 to 2016, were analyzed via data mining, descriptive, logistic regression, and sensitivity analyses. Drug use trends over time for cannabis and/or other substances (alcohol, illicit drugs, and medications) were assessed. Descriptive statistics (intent, external cause, and nature of injury) and proportionate injury ratios (PIR) associated with cannabis use are presented. RESULTS: Cannabis use was observed in 184 cases/100,000 eCHIRPP cases, and related injuries were mostly identified as unintentional (66.8%). Poisoning (68.5%) and intoxication (69.4%) were the external cause and nature of injury most associated with these events, and hospitalization was recorded for 14.3% of cases. Per 100,000 eCHIRPP cases, cannabis was used alone in 72.4 cases, and in combination with alcohol, illicit drugs, or medications in 74.6 cases, 11.3 cases, and 7.9 cases, respectively. Relative to non-use, the PIR of hospitalization was not significant for cannabis-only users of either sex (males: PIR 1.0, 95% CI 0.6-1.7, females: PIR 0.9, 95% CI: 0.5-1.7). CONCLUSION: Cannabis use injuries are rare, but can occur when cannabis is used with or without other substances. As Canada considers legislative changes, our finding of cases related to unintentional injury, poisoning, and intoxication suggests areas that might benefit from health literacy efforts.

Evaluating the early impacts of delisting high-strength opioids on patterns of prescribing in Ontario. / Évaluation des premiers effets du retrait des opioïdes à forte concentration sur les schémas de prescription en Ontario.

INTRODUCTION: Ontario delisted high-strength fentanyl, hydromorphone and morphine from the public drug formulary for non-palliative care prescribers on 31 January, 2017. Our aim is to assess the early impact of this policy on prescribing patterns and to examine whether this impact varied by prescriber type, opioid type and opioid strength. METHODS: We conducted a population-based, cross-sectional study on palliative and non-palliative care patients dispensed fentanyl, hydromorphone or morphine through the Ontario public drug program between 1 January, 2014, and 31 July, 2017. For each month during the study period, we reported the total number of high-strength opioid recipients stratified by prescriber type, and the total volume of each drug dispensed, stratified by strength. We used interventional autoregressive integrated moving average (ARIMA) models to assess the policy's impact on prescribing patterns. RESULTS: We observed a 98% decrease in the total number of publicly funded recipients of high-strength opioids between December 2016 and July 2017 (5930 to 133 recipients) for all prescribers. The policy led to a significant decline in the total volume of all three opioids dispensed: hydromorphone from 20 374 621 to 16 952 097 mg (p < .01); morphine from 40 644 190 to 33 555 480 mg (p < .03); and fentanyl from 9 604 913 to 5 842 405 mcg/h (p < .01). For both fentanyl and hydromorphone, this reduction generally corresponded to an increase in the number of low-strength opioids dispensed. CONCLUSION: Delisting high-strength opioids substantially reduced the number of highstrength opioid recipients and reduced the overall volume of long-acting opioids dispensed in Ontario through the public drug program. Future studies should examine its impact on patient outcomes.

INTRODUCTION: Le 31 janvier 2017, l'Ontario a retiré le fentanyl, l'hydromorphone et la morphine à forte concentration des médicaments remboursables par les programmes publics de médicaments s'ils sont prescrits par des médecins en soins non palliatifs. Nous avons voulu évaluer les premiers effets de cette politique sur les schémas de prescription et déterminer si ces effets variaient en fonction du type de prescripteur ainsi que du type d'opioïdes et de leur concentration. MÉTHODOLOGIE: Nous avons mené une étude transversale représentative de la population auprès de patients nécessitant des soins palliatifs et des soins non palliatifs à qui du fentanyl, de l'hydromorphone ou de la morphine couverts par les programmes publics de médicaments de l'Ontario avaient été prescrits entre le 1er janvier 2014 et le 31 juillet 2017. Pour chacun des mois de la période à l'étude, nous avons calculé le nombre total de patients ayant reçu des opioïdes à forte concentration (réparti par type de prescripteurs) ainsi que le volume total de chaque médicament délivré (réparti par concentration). Nous avons utilisé des modèles autorégressifs à moyennes mobiles intégrés (ARMMI) interventionnels pour évaluer les effets des changements apportés par la politique sur les habitudes de prescription. RÉSULTATS: Entre décembre 2016 et juillet 2017, le nombre total de patients ayant reçu des opioïdes à forte concentration remboursés par le régime public a diminué de 98 % pour l'ensemble des prescripteurs, passant de 5 930 à 133. La nouvelle politique a entraîné une baisse substantielle du volume total des trois opioïdes délivrés, soit de 20 374 621 à 16 952 097 mg (p < 0,01) pour l'hydromorphone, de 40 644 190 à 33 555 480 mg (p < 0,03) pour la morphine et de 9 604 913 à 5 842 405 mcg/h (p < 0,01) pour le fentanyl. Dans le cas du fentanyl et de l'hydromorphone, cette diminution a dans l'ensemble coïncidé avec une augmentation du nombre d'opioïdes à faible concentration délivrés. CONCLUSION: Le retrait des opioïdes à forte concentration a sensiblement réduit le nombre de patients à qui ces médicaments ont été prescrits, ainsi que le volume total d'opioïdes à action prolongée délivrés en Ontario dans le cadre du régime public de médicaments. D'autres études devraient être menées pour en examiner les effets sur les patients.

Risk of Lung Cancer Mortality in Nuclear Workers from Internal Exposure to Alpha Particle-emitting Radionuclides.

BACKGROUND: Carcinogenic risks of internal exposures to alpha-emitters (except radon) are poorly understood. Since exposure to alpha particles-particularly through inhalation-occurs in a range of settings, understanding consequent risks is a public health priority. We aimed to quantify dose-response relationships between lung dose from alpha-emitters and lung cancer in nuclear workers. METHODS: We conducted a case-control study, nested within Belgian, French, and UK cohorts of uranium and plutonium workers. Cases were workers who died from lung cancer; one to three controls were matched to each. Lung doses from alpha-emitters were assessed using bioassay data. We estimated excess odds ratio (OR) of lung cancer per gray (Gy) of lung dose. RESULTS: The study comprised 553 cases and 1,333 controls. Median positive total alpha lung dose was 2.42 mGy (mean: 8.13 mGy; maximum: 316 mGy); for plutonium the median was 1.27 mGy and for uranium 2.17 mGy. Excess OR/Gy (90% confidence interval)-adjusted for external radiation, socioeconomic status, and smoking-was 11 (2.6, 24) for total alpha dose, 50 (17, 106) for plutonium, and 5.3 (-1.9, 18) for uranium. CONCLUSIONS: We found strong evidence for associations between low doses from alpha-emitters and lung cancer risk. The excess OR/Gy was greater for plutonium than uranium, though confidence intervals overlap. Risk estimates were similar to those estimated previously in plutonium workers, and in uranium miners exposed to radon and its progeny. Expressed as risk/equivalent dose in sieverts (Sv), our estimates are somewhat larger than but consistent with those for atomic bomb survivors.See video abstract at, http://links.lww.com/EDE/B232.

Status report -- Childhood overweight and obesity in Canada: an integrative assessment. / Rapport d'étape -- Embonpoint et obésité chez les enfants au Canada : une évaluation globale.

INTRODUCTION: Obesity is a complex risk factor for chronic disease that is associated with a number of socioecological determinants. In this status report, we provide an overview of the socioecological framework that is now guiding our ongoing surveillance efforts in the area of childhood overweight and obesity. This framework considers individual risk and protective factors (sociodemographic, lifestyle, psychosocial and early-life) through the lens of the life stage, levels of influence and environments in which these factors play a role. METHODS: Using data from the Canadian Community Health Survey and the Canadian Health Measures Survey, univariate and bivariate analyses were used to report on behavioural, psychosocial, and early life factors associated with excess weight among Canadian children. RESULTS: Estimates of early-life (e.g. breastfeeding), behavioural (e.g. physical activity), and psychosocial factors (e.g. sense of community) are presented as they relate to age group, sex, income adequacy and weight status. CONCLUSION: Building upon our recent reporting on trends in and sociodemographic factors associated with childhood obesity in Canada, this work illustrates the remaining risk and protective factors shown in our surveillance framework. This analysis supports the shift towards a holistic appraisal of determinants related to healthy weights.

INTRODUCTION: L'obésité est un facteur de risque complexe des maladies chroniques associé à un certain nombre de déterminants socioécologiques. Ce rapport d'étape fournit un aperçu du cadre socioécologique qui guide actuellement nos efforts de suivi de l'embonpoint et de l'obésité chez les enfants. Ce cadre intègre différents facteurs de risque et de protection (facteurs sociodémographiques, liés au mode de vie, psychosociaux et en début de vie) et tient compte de l'étape de vie, des niveaux d'influence et de l'environnement au sein desquels ces facteurs jouent un rôle. MÉTHODOLOGIE: Nous avons effectué des analyses univariées et bivariées fondées sur les données de l'Enquête sur la santé dans les collectivités canadiennes et de l'Enquête canadienne sur les mesures de la santé pour rendre compte des facteurs comportementaux, des facteurs psychosociaux et des facteurs en début de vie associés à un surplus de poids chez les enfants canadiens. RÉSULTATS: Les estimations liées aux facteurs en début de vie (p. ex. l'allaitement), aux facteurs comportementaux (p. ex. l'activité physique) et aux facteurs psychosociaux (p. ex. le sentiment d'appartenance à la collectivité) sont présentées en fonction du groupe d'âge, du sexe, de la suffisance du revenu et du poids. CONCLUSION: Cette étude, qui s'appuie sur notre publication récente sur les tendances en matière d'obésité chez les enfants au Canada et les facteurs sociodémographiques qui y sont associés, présente les facteurs de risque et de protection intégrés à notre cadre de surveillance. D'après notre analyse, une évaluation plus globale des déterminants associés au maintien d'un poids santé est nécessaire.

Maternal exposure to ambient air pollution and risk of early childhood cancers: A population-based study in Ontario, Canada.

BACKGROUND: There are increasing concerns regarding the role of exposure to ambient air pollution during pregnancy in the development of early childhood cancers. OBJECTIVE: This population based study examined whether prenatal and early life (<1year of age) exposures to ambient air pollutants, including nitrogen dioxide (NO2) and particulate matter with aerodynamic diameters ≤2.5µm (PM2.5), were associated with selected common early childhood cancers in Canada. METHODS: 2,350,898 singleton live births occurring between 1988 and 2012 were identified in the province of Ontario, Canada. We assigned temporally varying satellite-derived estimates of PM2.5 and land-use regression model estimates of NO2 to maternal residences during pregnancy. Incident cases of 13 subtypes of pediatric cancers among children up to age 6 until 2013 were ascertained through administrative health data linkages. Associations of trimester-specific, overall pregnancy and first year of life exposures were evaluated using Cox proportional hazards models, adjusting for potential confounders. RESULTS: A total of 2044 childhood cancers were identified. Exposure to PM2.5, per interquartile range increase, over the entire pregnancy, and during the first trimester was associated with an increased risk of astrocytoma (hazard ratio (HR) per 3.9µg/m3=1.38 (95% CI: 1.01, 1.88) and, HR per 4.0µg/m3=1.40 (95% CI: 1.05-1.86), respectively). We also found a positive association between first trimester NO2 and acute lymphoblastic leukemia (ALL) (HR=1.20 (95% CI: 1.02-1.41) per IQR (13.3ppb)). CONCLUSIONS: In this population-based study in the largest province of Canada, results suggest an association between exposure to ambient air pollution during pregnancy, especially in the first trimester and an increased risk of astrocytoma and ALL. Further studies are required to replicate the findings of this study with adjustment for important individual-level confounders.

Risk factors for falls among seniors: implications of gender.

Despite extensive literature on falls among seniors, little is known about gender-specific risk factors. To determine the prevalence of falls by gender and sociodemographic, lifestyle/behavioral, and medical factors, we conducted a cross-sectional study in a nationally representative sample of Canadian adults who were 65 years of age or older (n = 14,881) from the Canadian Community Health Survey-Healthy Aging (2008-2009). Logistic regression models were applied to investigate gender-specific associations between potential risk factors and falls. In men, stroke (odds ratio (OR) = 1.91), nutritional risk (OR = 1.86), post-secondary school degree (OR = 1.68), eye disorder (OR = 1.35), widowed/separated/divorced marital status (OR = 1.28), and arthritis (OR = 1.27) were independently associated with significantly higher odds of falls. In women, significant independent correlates of falls included stroke (OR = 1.53), age of 85 years or older (OR = 1.51), nutritional risk (OR = 1.39), consumption of at least 1 alcoholic drink per week (OR = 1.39), use of 5 or more medications (OR = 1.36), arthritis (OR = 1.36), diabetes (OR = 1.31), and osteoporosis (OR = 1.22). Higher physical activity levels were protective in both genders, and higher household income was protective in women. Gender should be considered when planning fall prevention strategies.

Urinary inorganic arsenic in residents living in close proximity to a nickel and copper smelter in Ontario, Canada.

OBJECTIVES: The current study determines whether internal exposure to inorganic arsenic for residents living in close proximity to an operating smelter is any different from that for residents living in a similar community without anthropogenic sources of inorganic arsenic. Furthermore, the study examines factors that may contribute to internal inorganic arsenic exposure in these populations. METHODS: A cross-sectional study was used to determine whether recent internal exposure to inorganic arsenic for residents living in close proximity to an operating smelter with known elevated soil arsenic content is any different from exposure for residents living in a similar socio-demographic community without point sources of arsenic. Personal information was collected from participants during in-home interviews, and first morning void urine samples were obtained to assess recent internal exposure to arsenic. RESULTS: The mean concentration of urinary inorganic arsenic of residents living in the exposed community was 7.11 ug/L (Standard deviation (SD) 4.53, N = 368) and in the non-exposed community was 7.19 ug/L (SD 5.63, N = 321). The difference in urinary inorganic concentration was not statistically significant (p = 0.83). Regression analysis showed that age and sex were significant predictors of internal exposure, with males and younger age groups having higher exposure levels. CONCLUSIONS: Based on analyses of data collected, the results did not demonstrate a statistically significant difference in recent internal exposure to inorganic arsenic between the community with and the one without industrial or other point sources of environmental arsenic contamination. However, individual characteristics such as age and sex are important contributors to urinary inorganic arsenic levels.

Fourier-transform infrared spectroscopic study of characteristic molecular structure in cancer cells of esophagus: an exploratory study.

OBJECTIVE: To investigate the structural changes at the molecular level and to assess the usefulness of Fourier-transform infrared (FTIR) spectroscopy in the diagnosis of esophageal cancer. METHODS: A pilot study was established of 10 consecutive patients with adenocarcinoma of the esophagus. Tissue samples from the diseased and normal sites of the resected specimens were analyzed and compared using FTIR spectroscopy and histopathology. RESULTS: Specific changes were observed in the FTIR spectral features of esophageal cancer and thus spectral criteria were established for the detection of malignancy in esophagus tissues by FTIR spectroscopy. The spectral changes in cancer were the results of characteristic structural alterations at the molecular level in the esophageal cancer specimens. These alternations included an increase in the nuclei-to-cytoplasm ratio, an increase in the relative amount of DNA while a decrease in the relative amount of RNA, an enhancement in the phosphorylation of proteins, a decrease in the glycogen level, a loss of hydrogen bonding of the COH groups in the amino acid residues of proteins, a tighter intermolecular packing and a stronger intermolecular interaction among the DNA molecules, an increase in the distribution of protein segments with the conformation of beta-sheet and unordered turns and a tighter packing of the alpha-helical segments in overall tissue proteins, a decrease in the overall CH(3)-to-CH(2) ratio and an accumulation of triglycerides. CONCLUSIONS: FTIR is an automated method that has shown promise in differentiating cancer in the esophagus and may play a role in surveillance programs in premalignant conditions.

Chlorination disinfection by-products and pancreatic cancer risk.

Chlorination disinfection by-products (CDBPs) are produced during the treatment of water with chlorine to remove bacterial contamination. CDBPs have been associated with an increased risk of bladder cancer. There is also some evidence that they may increase the risk of pancreatic cancer. We report results from a population-based case-control study of 486 incident cases of pancreatic cancer and 3,596 age- and sex-matched controls. Exposure to chlorination by-products was estimated by linking lifetime residential histories to two different databases containing information on CDBP levels in municipal water supplies. Logistic regression analysis found no evidence of increased pancreatic cancer risk at higher CDBP concentrations (all odds ratios < 1.3). Null findings were also obtained assuming a latency period for pancreatic cancer induction of 3, 8, or 13 years.