Historical Exposure Research Articles

Kin networks and quality of government: a regional analysis

AbstractThis paper examines the relationship between kin-based institutions and quality of government in the regions of Spain, France, and Italy. The results show that the rate of cousin marriage during the twentieth century is a strong predictor of the modern-day quality of government in the regions of these three countries. Regions characterized by a higher prevalence of cousin marriage tend to have on average worse governance outcomes. This finding holds after accounting for country fixed effects and different variables that may be correlated with both consanguinity and regional quality of government, including an extensive array of geographical, historical, and contemporary factors. The observed association between cousin marriage and quality of government persists when I utilize an instrumental variable approach that exploits regional variation in the degree of historical exposure to the marriage laws of the medieval Catholic Church to address potential endogeneity concerns. Furthermore, the paper also provides evidence consistent with the idea that the effect of cousin marriage on the quality of government operates through its impact on a series of cultural traits such as impersonal trust, fairness, and conformity-obedience.

HANZE v2.1: an improved database of flood impacts in Europe from 1870 to 2020

Abstract. Assessing long-term trends in flood losses and attributing them to climatic and socioeconomic changes requires comprehensive and systematic collection of historical information. Here, we present flood impact data for Europe that are part of the HANZE (Historical Analysis of Natural HaZards) database. The dataset covers riverine, pluvial, coastal, and compound floods that have occurred in 42 European countries between 1870 and 2020. The data were obtained by extensive data collection from more than 800 sources ranging from news reports through government databases to scientific papers. The dataset includes 2521 events characterized by at least one impact statistic: area inundated, fatalities, persons affected. or economic loss. Economic losses are presented both in the original currencies and price levels and with the inflation and exchange rate adjusted to the 2020 value of the euro. The spatial footprint of affected areas is consistently recorded using more than 1400 subnational units corresponding, with minor exceptions, to the European Union's Nomenclature of Territorial Units for Statistics (NUTS) level 3. Daily start and end dates, information on causes of the events, notes on data quality issues or associated non-flood impacts, and full bibliography of each record supplement the dataset. Apart from the possibility of downloading the data (https://doi.org/10.5281/zenodo.8410025; Paprotny, 2023a), the database can be viewed, filtered, and visualized online at https://naturalhazards.eu (last access: 4 November 2024). The dataset is designed to be complementary to HANZE-Exposure, a high-resolution model of historical exposure changes (such as population and asset values) and be easily usable in statistical and spatial analyses, including multi-hazard studies.

Combined toxicity of perfluoroalkyl substances and microplastics on the sentinel species Daphnia magna: Implications for freshwater ecosystems

Persistent chemicals from industrial processes, particularly perfluoroalkyl substances (PFAS), have become pervasive in the environment due to their persistence, long half-lives, and bioaccumulative properties. Used globally for their thermal resistance and repellence to water and oil, PFAS have led to widespread environmental contamination. These compounds pose significant health risks with exposure through food, water, and dermal contact. Aquatic wildlife is particularly vulnerable as water bodies act as major transport and transformation mediums for PFAS. Their co-occurrence with microplastics may intensify the impact on aquatic species by influencing PFAS sorption and transport. Despite progress in understanding the occurrence and fate of PFAS and microplastics in aquatic ecosystems, the toxicity of PFAS mixtures and their co-occurrence with other high-concern compounds remains poorly understood, especially over organisms’ life cycles.Our study investigates the chronic toxicity of PFAS and microplastics on the sentinel species Daphnia, a species central to aquatic foodwebs and an ecotoxicology model. We examined the effects of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and polyethylene terephthalate microplastics (PET) both individually and in mixtures on Daphnia ecological endpoints. Unlike conventional studies, we used two Daphnia genotypes with distinct histories of chemical exposure. This approach revealed that PFAS and microplastics cause developmental failures, delayed sexual maturity and reduced somatic growth, with historical exposure to environmental pollution reducing tolerance to these persistent chemicals due to cumulative fitness costs. We also observed that the combined effect of the persistent chemicals analysed was 59% additive and 41% synergistic, whereas no antagonistic interactions were observed. The genotype-specific responses observed highlight the complex interplay between genetic background and pollutant exposure, emphasizing the importance of incorporating multiple genotypes in environmental risk assessments to more accurately predict the ecological impact of chemical pollutants.

Surveillance of asbestos related disease among workers enrolled in an exposure registry.

Contemporary asbestos exposure occurs during construction, remediation, and maintenance involving asbestos-containing materials (ACM), as compared to the historical exposure scenarios of asbestos mining and milling. The Ontario Asbestos Workers Register (AWR) was established in 1986 to track asbestos exposure among construction workers. This study reports on the risk of asbestos-related diseases (ARD) among workers in the AWR. AWR registrants were linked probabilistically with administrative health databases (1986-2019) to identify cases of ARD including both cancer and chronic respiratory disease. Follow-up began at AWR enrollment and continued prospectively. Incidence rates were compared to the general population using standardized incidence ratios (SIRs). Associations between ACM exposure and ARD were estimated among AWR registrants using Poisson regression. In total, 26,204 (81%) registrants were linked successfully. Common industries of employment were construction (62%), manufacturing (19%) and education (8%). Among men and women mesothelioma (M:SIR 6.83 [95% CI = 5.56-8.31]; W:SIR 19.2 [3.86-56.1]) and pulmonary fibrosis (M:SIR 14.1 [12.2-16.2]; W:SIR 9.25 [2.49-23.7]) rates were higher than the general population. Asbestosis risk was elevated among men (M:SIR 11.2 [9.59-13.1]). Workers with longer reported exposures (≥140 h) had increased rates of lung cancer (RR 1.34 [1.10-1.63]), mesothelioma (RR 2.83 [1.75-4.58]), asbestosis (RR 3.07 [2.12-4.43]), chronic obstructive pulmonary disease (RR 1.42 [1.29-1.57]), and pulmonary fibrosis (RR 1.88 [1.35-2.62]). Exposure to asbestos in construction and building maintenance continues to contribute to ARD incidence. Despite a Canadian ban on asbestos in new products, exposures to existing ACM will persist from construction activities. The AWR offers an opportunity for ongoing surveillance of resulting ARD in Ontario.

Comparison of a radiofrequency electric and magnetic field source-based job-exposure matrix with personal radiofrequency exposure measurements.

Assessing occupational exposure to radiofrequency electromagnetic fields (RF-EMF) presents significant challenges due to the considerable variability in exposure levels within and between occupations. This spatial and temporal variability complicates the reliable evaluation of potential health risks associated with RF-EMF exposure in the workplace. Accurate assessment methods are crucial to understand the extent of exposure and to evaluate potential health risks, especially given the potential for higher exposures in occupational settings compared to the general population. This study compares the historical RF-EMF exposure estimates in the INTEROCC RF-EMF job-exposure matrix (RF-JEM) with recent personal measurement data collected in 2 countries as part of the OccRF-Health study, to assess the broader applicability of the RF-JEM. Weighted kappa (k w) coefficients and Spearman rank correlation tests were performed to assess the alignment between RF-JEM estimates and measurements for 8h time-weighted average exposure intensity and prevalence estimates across various occupations. The comparisons were mainly based on 22 jobs having ≥5 measured workers in the OccRF-Health study. Poor agreement was found for both exposure prevalence and intensity between both methods (k w < 0.1). RF-JEM values likely overestimated exposure levels for both electric (E) and magnetic (H) fields (mean percentage difference >194%) compared to current personal measurements. Findings suggest that the INTEROCC-JEM likely overestimates current exposure intensity levels in the measured jobs. Adopting a semiquantitative JEM could also mitigate misclassification errors due to exposure variability, improving accuracy in exposure assessment. These findings indicate the need for more targeted personal measurements, including among highly exposed workers, and for potentially considering new exposure metrics to more accurately assess occupational RF-EMF exposures in occupational epidemiological research.

The prevalent trajectory of early menopause associated with PM2.5 exposure across 1956–2018 extrapolated from LightGBM algorithm

BackgroundFine particulate matter (PM2.5) is noxious to female reproductive development and facilitates the occurrence of subsequent diseases. Early menopause is initiative factor of female aging. But due to the lack of historical exposure of PM2.5, we could not gain insight into the linkage between ambient PM2.5 exposure and early menopause. MethodsWe conducted a community-based retrospective cross-sectional study and pooled 1173 postmenopausal women. The machine learning algorithm of LightGBM was processed to derive the historical concentrations of PM2.5 based on aerography of 1956–2022. The quantile g-computation and binary logistic regression were employed to estimate the mixed and single associations between PM2.5 and early menopause. ResultsThe visibility topped the most important feature for derivations of historical PM2.5 concentrations. The R2 of 10-fold cross-validation and predictive capability during processing were all above 0.8. The prevalence of early menopause was 7.3 %. Each 10 µg/m3 PM2.5 increased the prevalence of early menopause during prior 2 years exposure (OR: 1.49, 95 %CI: 1.03–2.16) and spring and autumn (OR: 1.28, 95 %CI: 1.07–1.54). After adjusting the reverse effects of temperature, the prior 2 years exposure of PM2.5 remained positively associated with early menopause in the fourth quantile vs the first quantile (OR: 3.36, 95 %CI: 1.53–7.36) in the spring and autumn. The higher BMI (OR: 1.40, 95 %CI: 1.14–1.72), waistline (OR: 1.42, 95 %CI: 1.09–1.85) and unfavourable dietary habits of less meat (OR: 1.72, 95 %CI: 1.11–2.68), more fried food (OR: 2.39, 95 %CI: 1.15–4.99) elevated the prevalence of early menopause. ConclusionsThe accurate environmental exposure assessment of historical PM2.5 vigorously promoted the researches on the relationship between PM2.5 and early menopause. It sounds the alarm on female infertility menace associated with particulate matter especially during the turbulent 2 years before menopause.

Older Adult Family Homicide in Victoria, Australia 2001–2015: A Description of Family and Family Violence Homicide Victimisation

Abstract Purpose This study examined factors present among older adult family homicide victims and their offenders compared to younger adult family homicide using the social-ecological model. Method The study used a population-based single-jurisdiction cross-sectional design of consecutive homicide cases of adults (aged 18 years and older) reported to the coroner in Victoria, Australia for the period 2001–2015. Included were homicides involving an intimate or familial relationship. The data source was the Victorian Homicide Register, maintained by the Coroners Court of Victoria. Descriptive and multivariate analysis was performed to compare the presence of factors between younger and older adult family homicides. Results During the study period 37/283 (13.1%) family homicides occurred among older adult victims (aged 65 years and older) and 246/283 (86.9%) occurred among younger adults (aged 18–64 years). The deceased older adult was often male (57%), with a documented physical illness (54%). Offenders against the older adult were frequently male (68%), non-intimately related (73%), with diagnosed mental illness, a history of substance use and/or historical exposure to violence (all 57%). There were 15 older adult family violence (FV) homicide victims, eight that were previously victims of the homicide offender, primarily enduring emotional, physical and psychological violence as well as the perpetrator assaulting another family member. Seven older adults had perpetrated FV against their offender. Conclusions The history of violence perpetration in the deceased and mental health factors in their offender, as well as the greater proportion of parent-child and other familial relationships offer interesting focal points for future prevention research.

Historical exposure to metals in contaminated areas and its impact on cardio- and cerebrovascular health

Environmental pollution is of global concern. In Southeast Sweden, historical glass production has contaminated communities with toxic metals. Long-term residency in these communities and high consumption of local foods may constitute a risk for cardiovascular disease (CVD) or stroke.The current study investigates if residency in these contaminated sites and long-term consumption of local foods is associated with self-reported CVD and stroke. In addition, the body burden of the toxic metals arsenic, cadmium, and lead, as well as inflammatory protein markers, were studied for association with CVD and stroke.From an existing questionnaire cohort and biomonitoring sub cohort (n = 2290/882) of people living in the contaminated areas, self-reported CVD cases (n = 366/166) and stroke cases (n = 78/25) were identified. Individuals were grouped based on their residency within a 2 km radius of glassworks with historical high, moderate, or low air-borne lead emissions. Body burden of arsenic, cadmium, and lead was analyzed using ICP-MS. Inflammatory markers were investigated using electrochemiluminescence.Long-term residency near glassworks with historically high levels of lead emissions, and high consumption of local foods, were associated with CVD. The risk was increasing for each year of residency in high emission areas. Increased body burden of arsenic in blood, and lead in urine, were associated with stroke. Five and two inflammatory markers, respectively, were elevated in CVD and stroke cases after adjusting for confounders.An increased risk for CVD was found in areas with historically high emissions of lead but possibly also other toxic metals. Interestingly, there was an indication of a dose-response relationship with increasing risk for CVD per year of residency time. Inhalation and consumption of local food may constitute major pathways for this association. The study shows that long-term exposure to toxic metals in these contaminated areas is associated with CVD and that there is a need to limit exposure in the general population.

Historical Pollution Exposure Impacts on PM2.5 Dry Deposition and Physiological Responses in Urban Trees

Historical Pollution Exposure Impacts on PM2.5 Dry Deposition and Physiological Responses in Urban Trees

Bauxite mine and alumina refinery workers: mortality and cancer risk.

Aluminium industry workers are at risk of long-term health consequences. To investigate mortality and cancer incidence in bauxite mine and alumina refinery workers. A pre-existing cohort of workers was re-linked with the Australian National Death Index, and the Australian Cancer Database to provide additional death (7 years) and cancer (9 years) data. Standardized mortality ratios (SMRs) and standardized incidence rates (SIRs) were estimated by job category, duration of employment and time since first employment. Linkage was performed for 6935 (6207 male) workers. Compared with the general population, there was a reduced or similar risk of death for mine/refinery workers for all causes except mesothelioma which was increased amongst male production workers [SMR 2.42, 95% CI 1.11-4.60]. Mesothelioma incidence was also increased amongst males [SIR 2.50, 95% CI 1.60-3.71]. Male office workers had a greater incidence of prostate cancer [SIR 1.30, 95% CI 1.06-1.57] and thyroid cancer [SIR 3.47, 95% CI 1.66-6.38]. Melanoma incidence was increased in female office workers [SIR 2.27, 95% CI 1.36-3.54]. Lip cancer incidence was increased in male maintenance/production workers [SIR 2.04, 95% CI 1.02-3.65]. Overall cancer incidence was otherwise similar to the general Australian population. Overall risk of death and incidence of cancer for bauxite mine and alumina refinery workers was similar to the general population. Incidence and risk of death from mesothelioma were higher, likely due to historic asbestos exposure in this and other industries. The increased risk of melanoma, lip, prostate and thyroid cancers requires further investigation.

Interactions between phenanthrene exposure and historical chemical stress: Implications for fitness and ecological resilience of the sentinel species Daphnia magna

Polycyclic aromatic hydrocarbons (PAHs) arise from incomplete combustion of oil, coal, and gasoline, with lipophilic properties facilitating their widespread distribution and persistence. Due to their biochemical attributes, PAHs can accumulate in animal tissues, potentially causing mutagenic and carcinogenic effects. Since the industrial revolution, PAH concentrations in the environment have risen, with lakes showing levels from 0.159 to 33,090 μg/kg sediment. Despite acute toxicity studies showing adverse effects on freshwater organisms, the long-term impacts and synergistic interactions with other pollutants remain largely unexplored.This study investigates the impact of phenanthrene (PHE), a prominent PAH found in aquatic environments, on Daphnia magna, a species of significant ecological importance in freshwater ecosystems globally, being both a sentinel species for chemical pollution and a keystone organism in freshwater aquatic ecosystems. Leveraging the dormancy of D. magna, which spans decades or even centuries, we exposed strains with diverse histories of chemical contaminant exposure to environmentally relevant concentrations of PHE. Initially, acute exposure experiments were conducted in accordance with OECD guidelines across 16 Daphnia strains, revealing substantial variation in acute toxic responses, with strains naïve to chemical pollutants showing the lowest toxicity. Utilizing the median effect concentration EC10 derived from acute exposures, we assessed the impacts of chronic PHE exposure on life history traits and ecological endpoints of the 16 strains. To elucidate how historical exposure to other environmental stressors may modulate the toxicity of PHE, temporal populations of D. magna resurrected from a lake with a well-documented century-spanning history of environmental impact were utilized. Our findings demonstrate that PHE exposure induces developmental failure, delays sexual maturation, and reduces adult size in Daphnia. Populations of Daphnia historically exposed to chemical stress exhibited significantly greater fitness impacts compared to naïve populations. This study provides crucial insights into the augmented effects of PAHs interacting with other environmental stressors.

Asbestos-Related lung Cancer: An underappreciated oncological issue

Asbestos, a group of class I (WHO) carcinogenic fibers, is the main cause of mesothelioma. Asbestos inhalation also increases the risk to develop other solid tumours with lung cancer as the most prominent example [91]. The incidence of asbestos-related lung cancer (ARLC) is estimated to be to six times larger than the mesothelioma incidence thereby becoming an important health issue [86]. Although the pivotal role of asbestos in inducing lung cancer is well established, the precise causal relationships between exposures to asbestos, tobacco smoke, radon and ‘particulate’ (PM2.5) air pollution remain obscure and new knowledge is needed to establish appropriate preventive measures and to tailor existing screening practices[22,61,65]. We hypothesize that a part of the increasing numbers of lung cancer diagnoses in never-smokers can be explained by (historic and current) exposures to asbestos as well as combinations of different forms of air pollution (PM2.5, asbestos and silica).

Leisure Activity, Childhood Starvation, and Risk of Incident Diabetes in Older Adults: Evidence from a Chinese Nationwide Cohort Study

ObjectiveThis study explores the impact of leisure activity and the association between childhood starvation and the risk of diabetes in older Chinese adults. DesignProspective cohort study based on the Chinese Longitudinal Healthy Longevity Study (CLHLS), a nationwide cohort study in China. Setting and participantsA total of 4637 older adults aged ≥65 years, all with documented diabetes history, experiences of childhood starvation, and participation in leisure activities were recruited. MethodsChildhood starvation exposure was assessed via self-reported responses from a structured questionnaire. The leisure activities were measured by 9 distinctive components and categorized into 3 distinct categories: productive activity, recreational activity, and sedentary activity. Diabetes status was determined by self-reported, physician-diagnosed cases during the follow-up period. Nonparametric survival models were employed for analysis. ResultsOver an average follow-up period of 4.3 years, 215 of 4637 participants (4.6%) reported a confirmed diagnosis of diabetes. Nonparametric survival models showed that those reporting childhood starvation had a higher risk of late-life diabetes [hazard ratio (HR) 1.72, 95% CI 1.21-2.44]. Engaging in productive activity (HR 0.90, 95% CI 0.83-0.99) and recreational activity (HR 0.88, 95% CI 0.77-1.00) was linked with a reduced risk of late-life diabetes. Sedentary activity did not show a significant effect. Further analysis highlighted the interactions effects of leisure activities on diabetes risk across different demographic and historical exposure subgroups. Conclusions and implicationsEngaging in productive and recreational leisure activities was inversely associated with the risk of diabetes in older adults who experienced childhood starvation. Promoting such activities could be beneficial in mitigating long-term diabetes risk related to early-life nutritional deficiencies.

Slave trades, kinship structures and women's political participation in Africa

AbstractWe study whether present‐day women's political participation in sub‐Saharan Africa is associated to the temporary gender ratio imbalances caused by the transatlantic and Indian Ocean slave trades, taking into account pre‐existing gender norms influenced by kinship structures. To study the interrelatedness between historical exposure to the slave trades, patrilineality and their association to contemporary women's political participation, we use individual‐level data for 35,595 women from 28 sub‐Saharan African countries from three rounds of Afrobarometer surveys, georeferenced to historical ethnic region kinship and slave trade data. Our findings suggest that a woman's ethnic region historical exposure to the transatlantic slave trade is associated with an increase in her likelihood to vote today, however, only in non‐patrilineal ethnic regions. This effect is mitigated in patrilineal ethnic regions, where women have less decision‐making power. This paper contributes to the literature on the contemporary sub‐national effects of the slave trades and the historical causes of gender gaps in political participation.

Asbestos exposures associated with the use and handling of drilling mud additives.

This paper summarizes historical asbestos exposure data collected during the handling of short-fiber chrysotile asbestos that was used as an additive to drilling fluid in oil and gas exploration. A total of 1171 industrial hygiene (IH) personal and area air samples were collected and analyzed from more than 20 drilling rigs between 1972 and 1985. The dataset consists of 1097 short-term samples (<240min) with more than 80% having sample durations less than 30min. Average airborne fiber concentrations measured during asbestos handling activities ranged from 0.62 f/cc to 3.39 f/cc using phase-contrast microscopy (PCM). An additional 14 samples were considered long-term samples (>240min) and there were 60 samples with no reported sample duration. Eight-hour time-weighted average (8-h TWA) results, calculated using short-term samples, along with long-term samples greater than 240min, did not exceed contemporaneous Occupational Safety and Health Administration (OSHA) permissible exposure limits (PELs). This analysis fills a data gap in the evaluation of asbestos exposures from the use of drilling mud additives (DMAs) that contained chrysotile asbestos.

Estimating impacts of reducing acrylonitrile exposure on lung cancer mortality in an occupational cohort with the parametric g-formula

ObjectivesTo inform the potential human carcinogenicity of acrylonitrile, we estimate associations between acrylonitrile exposures and lung cancer mortality in US workers with the objectives of (1) assessing potential for healthy...

Systematic investigation of organochlorine pesticides and polychlorinated biphenyls blood levels in Greek children from the Rhea birth cohort suggests historical exposure to DDT and through diet to DDE

The blood levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) have been thoroughly investigated in Greek children from the Rhea birth cohort study. This investigation aimed to assess exposure levels, explore their possible relationship with children's age and sex, and indicate potential sources of exposure. Exposure patterns and common sources of PCBs and OCPs were analyzed using bivariate and multivariate statistics.A total of 947 blood samples from study participants were analyzed for OCP and PCB exposure, with 375 samples collected at 4 years old, 239 at 6.5 years old, and 333 at 11 years old. Elevated levels of DDE were observed in 6.5-year-old children compared to corresponding levels in other European countries. Higher levels of DDE were found in 4-year-old children, with the lowest concentrations in the 11-year-old group. The DDT/DDE ratio was consistently less than 1 among all the examined subjects. These results indicate exposure to DDT and DDE both in utero and through breastfeeding and dietary intake. For the entire cohort population, the highest concentration was determined for PCB 28, followed by PCBs 138, 153, and 180. The sum of the six indicator PCBs implied low exposure levels for the majority of the cohort population. Spearman correlations revealed strong associations between PCBs and OCPs, while principal component analysis identified two different groupings of exposure. DDE exhibited a correlation with a series of PCBs (153, 156, 163, 180), indicating a combined OCP-PCB source, and an anticorrelation with others (52, 28, 101), implying a separate and competing source.

Long-term exposure to ambient fine particulate matter and risk of liver cancer in the NIH-AARP Diet and Health Study

BackgroundFine particulate matter (PM2.5) exposure has been associated with liver cancer incidence and mortality in a limited number of studies. We sought to evaluate this relationship for the first time in a U.S. cohort with historical exposure assessment. MethodsWe used spatiotemporal prediction models to estimate annual average historical PM2.5 concentrations (1980–2015) at residential addresses of 499,729 participants in the NIH-AARP Diet and Health Study, a cohort in 6 states (California, Florida, Louisiana, New Jersey, North Carolina, and Pennsylvania) and 2 metropolitan areas (Atlanta, Georgia, and Detroit, Michigan) enrolled in 1995–1996 and followed up through 2017. We used a time-varying Cox model to estimate the association for liver cancer and the predominant histologic type, hepatocellular carcinoma (HCC), per 5 µg/m3 increase in estimated outdoor PM2.5 levels, incorporating a 5-year average, lagged 10 years prior to cancer diagnosis and adjusting for age, sex, race/ethnicity, education level and catchment state. We also evaluated PM2.5 interactions with hypothesized effect modifiers. ResultsWe observed a non-significantly increased risk of liver cancer associated with estimated PM2.5 exposure (Hazard ratio [HR] = 1.05 [0.96–1.14], N = 1,625); associations were slightly stronger for HCC, (84 % of cases; HR = 1.08 [0.98–1.18]). Participants aged 70 or older at enrollment had an increased risk of liver cancer versus other age groups (HR = 1.50 [1.01–2.23]); p-interaction = 0.01) and risk was elevated among participants who did not exercise (HR = 1.81 [1.22–2.70]; p-interaction = 0.01). We found no evidence of effect modification by sex, smoking status, body mass index, diabetes status, or alcohol consumption (p-interaction > 0.05). ConclusionsOur findings in this large cohort suggest that residential ambient PM2.5 levels may be associated with liver cancer risk. Further exploration of the variation in associations by age and physical activity are important areas for future research.

Pesticide exposure and risk of cholangiocarcinoma: A hospital-based matched case-control study.

Cholangiocarcinoma (CCA) caused by Opisthorchis viverrini is a well-known and significant public health issue in northeastern Thailand; however, a link between pesticide exposure (PE) and CCA risk has not yet been established. Therefore, our research objective was to investigate the relationship between PE and CCA risk. A hospital-based matched case-control study was carried out. All cases (in-patients) and controls (out-patients) were volunteers at a tertiary hospital in northeast Thailand. Between 2015 and 2019, 178 incident cases of pathologically-confirmed CCA and 356 controls were selected from the check-up clinic from the Srinagarind Hospital outpatient database (two controls per case). The recruited controls were individually-matched to the CCA cases based on sex, age (±5 years) and admission date (±3 months). During face-to-face interviews, a standardised pre-tested questionnaire was used to collect data. Multivariable conditional logistic regression was used to analyse the data. The respective frequency of PE between the 178 CCA cases and 356 controls was 77.0% versus 87.6% for never used, 14.6% versus 5.3% for have used but stopped and 8.4% versus 7.0% for currently using. After adjusting for the highest educational attainment, smoking behaviour, alcohol use and family history of cancer, PE was not significantly associated with CCA (p-value = 0.086). Using volunteers who have never used PE as the reference group, the respective odds of developing CCA for those who have ever used but have since stopped and are currently using was 2.04 (adjusted OR = 2.04; 95% CI: 1.03-4.04) versus 0.83 (adjusted OR = 0.83; 95% CI: 0.39-1.76) times more likely to develop CCA than those who had never used PE. There is no association between PE and the risk of CCA. Notwithstanding the finding, future research should focus on enhancing PE assessment methods that consider complex chemical mixtures, chemicals of interest, historical exposure and exposure pathways. Moreover, there is need for more extensive and longer population-based cohort studies that include younger, non-occupationally exposed individuals during periods of developmental susceptibility.

Early life exposure of infants to benzylpenicillin and gentamicin is associated with a persistent amplification of the gut resistome

BackgroundInfant gut microbiota is highly malleable, but the long-term longitudinal impact of antibiotic exposure in early life, together with the mode of delivery on infant gut microbiota and resistome, is not extensively studied.MethodsTwo hundred and eight samples from 45 infants collected from birth until 2 years of age over five time points (week 1, 4, 8, 24, year 2) were analysed. Based on shotgun metagenomics, the gut microbial composition and resistome profile were compared in the early life of infants divided into three groups: vaginal delivery/no-antibiotic in the first 4 days of life, C-section/no-antibiotic in the first 4 days of life, and C-section/antibiotic exposed in first 4 days of life. Gentamycin and benzylpenicillin were the most commonly administered antibiotics during this cohort’s first week of life.ResultsNewborn gut microbial composition differed in all three groups, with higher diversity and stable composition seen at 2 years of age, compared to week 1. An increase in microbial diversity from week 1 to week 4 only in the C-section/antibiotic-exposed group reflects the effect of antibiotic use in the first 4 days of life, with a gradual increase thereafter. Overall, a relative abundance of Actinobacteria and Bacteroides was significantly higher in vaginal delivery/no-antibiotic while Proteobacteria was higher in C-section/antibiotic-exposed infants. Strains from species belonging to Bifidobacterium and Bacteroidetes were generally persistent colonisers, with Bifidobacterium breve and Bifidobacterium bifidum species being the major persistent colonisers in all three groups. Bacteroides persistence was dominant in the vaginal delivery/no-antibiotic group, with species Bacteroides ovatus and Phocaeicola vulgatus found to be persistent colonisers in the no-antibiotic groups. Most strains carrying antibiotic-resistance genes belonged to phyla Proteobacteria and Firmicutes, with the C-section/antibiotic-exposed group presenting a higher frequency of antibiotic-resistance genes (ARGs).ConclusionThese data show that antibiotic exposure has an immediate and persistent effect on the gut microbiome in early life. As such, the two antibiotics used in the study selected for strains (mainly Proteobacteria) which were multiple drug-resistant (MDR), presumably a reflection of their evolutionary lineage of historical exposures—leading to what can be an extensive and diverse resistome.31ajk8a-14RKZLdCXmKHuwVideo