Excess Cancer Risk Research Articles

Excess pancreatic cancer risk due to smoking and modifying effect of quitting smoking: The Multiethnic Cohort Study

PurposeRisk factors for pancreatic cancer include racial/ethnic disparities and smoking. However, risk trajectories by smoking history and race/ethnicity are unknown. We examined the association of smoking with pancreatic cancer by race/ethnicity to generate age-specific incidence estimates by smoking history.MethodsWe modeled pancreatic cancer incidence by race/ethnicity, age, pack-years, and years-quit using an excess relative risk model for 182,011 Multiethnic Cohort participants. We tested heterogeneity of smoking variables and pancreatic cancer by race/ethnicity and predicted incidence by smoking history.ResultsWe identified 1,831 incident pancreatic cancer cases over an average 19.3 years of follow-up. Associations of pack-years (p interaction by race/ethnicity = 0.41) and years-quit (p interaction = 0.83) with pancreatic cancer did not differ by race/ethnicity. Fifty pack-years smoked was associated with 91% increased risk (95% CI 54%, 127%) relative to never smokers in the combined sample. Every year quit corresponded to 9% decreased excess risk (95% CI 2%, 15%) from pack-years smoked. Differences in baseline pancreatic cancer risk across racial/ethnic groups (p < 0.001) translated to large differences in risk for smokers at older ages across racial/ethnic groups (65–122 cases per 100,000 at age 70).ConclusionSmoking pack-years were positively associated with elevated pancreatic cancer risk. Predicted risk trajectories showed a high impact of smoking cessation at < 65 years. Although we did not identify significant heterogeneity in the association of pack-years or years quit with pancreatic cancer risk, current smoker risk varied greatly by race/ethnicity in later life due to large differences in baseline risk.

Health risk analysis of benzene, toluene, ethylbenzene, and xylene (BTEX) in groundwater in Yogyakarta City, Indonesia

Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) are persistent and bio-accumulative compounds that occur in petroleum-based products. Benzene is categorized as a carcinogenic substance while ethylbenzene is potentially carcinogenic. One of the sources of BTEX contamination in the environment is gas stations. The leakage of underground storage tanks (UST) of gas stations is a potential source of groundwater contamination, while in many areas, it is the main source of daily water consumption. The long-term consumption of this BTEX-contaminated groundwater may generate health risks. This paper will present the health risk analysis of the consumption of BTEX-contaminated groundwater taken from dug wells near a gas station in Yogyakarta City which has a history of major leakage. Analysis of BTEX in groundwater samples has been already presented in the previous study. Data for intake calculation was acquired through questionnaires and interviews on water consumption patterns. Risk analysis was conducted for both the carcinogenic effect of benzene and the non-carcinogenic effect for all BTEX compounds. Health risk analysis on BTEX exposure in groundwater resulted in the Hazard Quotient (HQ) value for all compounds which were still less than one, meanwhile, the Excess Cancer Risk (ECR) for benzene was less than 10-4. The result indicates the low health risk associated with the consumption of BTEX-contaminated groundwater in the study area.

Analysis of the radiological dose and hazards assessment around swampy agricultural soil in Keffi, Nasarawa State, Nigeria

The present study analyzes radiological dose and hazard around the swampy agricultural soil in Keffi Local Government Area of Nasarawa State, using determined activity concentration (AC) of 238U, 232Th and 40K obtained from swampy agricultural soil samples, systematically collected from Ten (10) sampled points. Samples collected were further analyzed using a sodium iodide detector for activity concentrations of 238U, 232Th and 40K. The average AC of 238U, 232Th and 40K were 26.73±4.64, 9.77±2.57 and 1115.52 ±67.43 Bq/kg, respectively. The gamma absorbed dose rate (Dabs) ranges from 6.37E-01 to 2.33E+01 nGy/hr with a mean value of 6.10E+00 nGy/hr. The annual effective dose equivalent (AEDE) ranges from 8.12E-03 to 2.97E-01 mSv/yr with an estimated mean value of 7.77E-02 mSv/yr. The annual gonadal dose equivalent ranges from 4.48E-02 to 1.72E+01 mSv/yr with a mean value of 4.49E-01 mSv/yr. The calculated radium equivalent activity ranges from 1.44E+01 to 4.49E+02 Bq/kg with a mean value of 1.18E+02 Bq/kg, which falls below the recommended standard value of 3.7E+02 Bq/kg. The external and internal hazard index ranges from 3.89E-02 to 1.21E+00 mSv/yr with a mean value of 3.20E-01 mSv/yr, and 3.90E-02 to 1.41E+00 mSv/yr with a mean value of 3.70E-01 mSv/yr. The gamma hazard index ranges from 5.24E-02 to 1.84E+00 mSv/yr with a mean value of 4.83E-01 mSv/yr. The activity utilization index ranges from 8.65E-02 to 1.34E+00 mSv/yr with a mean value of 3.82E-01 mSv/yr, excess life cancer risk (ELCR) for both adult and child was found to be 1.94E-01 and 2.72E-01, respectively, higher than the recommended world average value of 0.29E-03. The high value of ELCR implies that residents around the study area have a high chance of developing cancer over a lifetime. Hence periodic radiological dose and hazard analysis is recommended to keep the exposure as low as reasonably achievable.

Risk assessment for conventional diesel exhaust (before 1990) and lung cancer in a cohort of miners.

Diesel exhaust in the latter half of the 20th century has been found to be a lung carcinogen. Conventional diesel emissions continue in the transportation, mining, construction, and farming industries. From the Diesel Exhaust in Miners Study, a public-use dataset was used to calculate the excess lifetime risk of lung cancer associated with diesel exposure (1947-1997). Excess rates of lung cancer mortality associated with respirable elemental carbon (REC) and possible other mining exposures (e.g., oil mists, explosives emissions) were investigated using Poisson regression methods. Lung cancer mortality declined with increasing employment duration while increasing with cumulative REC and non-diesel exposures, suggesting a strong worker survivor effect. Attenuation of the REC effect was observed with increasing cumulative exposure. After adjustment for employment duration, the excess rate ratio for lung cancer mortality was 0.67 (95% CI=0.35-0.99) for a 10-year lagged exposure to 200μg/m3 REC, a typical below-ground exposure in the study mines. At exposures of 200, 10, and 1μg/m3 REC, the estimated excess lifetime risks, respectively, were 119, 43, and 8.7 per thousand. Analysis of an inception cohort hired after dieselization commenced produced smaller and less certain estimates of lifetime risk. From exposures to conventional diesel engine exhaust common in occupational groups in the past, the excess lifetime risk of lung cancer was more than 5%. Ambient REC exposures in the general population were estimated to confer lifetime risks of 0.14 to 14 per thousand, depending on assumptions made.

Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Seafood from Orashi River in Omoku, Rivers State of Nigeria and Human Health Risk Assessment

This study investigated the level of polycyclic aromatic hydrocarbons (PAHs) in seafood, namely, C. sapidus (Crab), P. mollusca (Mollusc), Cambarus sp. (Crayfish), Caridea (Shrimp) from Orashi River in Omoku, Rivers State of Nigeria. The PAHs in the samples were determined by gas chromatography–mass spectrometry. There was no variation in the relative level of PAHs congeners. The mean concentrations of individual PAHs decreased in the order: D(a,h)ant > Pyr > Fluth > B(g,h,i)p > B(a)A > B(b)f > Ind (1,2, 3)pyr > B(a)pyr > Chr > B(k)flu > Ant > Flu > Phen > Aceth > Ace > Nap. Anthracene contributed the highest PAHs values, with 51.685% in Caridea. The EDI values of B(a)P, Ʃ2PAH, Ʃ4PAH, Ʃ8PAH across all the seafood were within the maximum permissible limit recommended by EFSA; this suggests that the accumulation of the PAHs in the body system are within the permitted levels. Similarly, the HI of the PAHs congeners obtained from this study were less than 1 which is the safe limit recommended by USEPA. The total Excess Cancer Risk of the PAHs congeners obtained from this study exceeded the permissible maximum limit recommended by USEPA. This study suggests that the water may be contaminated with PAHs which have the tendency to cause non-carcinogenic and carcinogenic risk because of frequent and high consumption of seafoods.

No excess cancer risk for non-erosive disease.

No excess cancer risk for non-erosive disease.

Mapping of uranium in groundwater of Mysuru district, Karnataka, India and radiation dose to the population

Uranium in ground and surface water may pose significant health hazards, if they are ingested via drinking pathway because of its radiological and chemical toxicities. Higher uranium concentration in drinking water can lead to serious diseases like leukemia, kidney cancer, stomach cancer and renal damages etc. In the present investigation, uranium concentration in groundwater samples of Mysuru district has been studied using an LED fluorimeter. About 350 water samples have been collected covering all the areas of Mysuru district and the uranium concentration varied from 0.34 to 242.93 µg l−1. The age depended dose due to uranium in drinking water has been estimated to evaluate the health hazards. The annual ingestion dose varied from 0.51 to 95.76 µSv y−1. The radiological and chemical toxicity risk to the population due to uranium in water was estimated. The Excess Cancer Risk varied from 1.22 × 10−6 to 102.63 × 10−6. The mean value of Hazard Quotient 0.07 indicates that the populations are less prone to adverse health effects of uranium contamination in water.

Cancer incidence among visual artists: 45 years of follow-up in four Nordic countries

Introduction Professional visual artists constitute a heterogeneous vocational group, including, but not limited to painters, photographers, textile artists, and sculptors who may face exposure to workplace hazardous substances and lifestyle factors that may contribute to the development of selected cancers. The objective of this registry-based cohort study was to assess the cancer incidence among Nordic visual artists. Materials and methods This study is based on data from the Nordic Occupational Cancer (NOCCA) project that combines census data of 15 million people from all Nordic countries and cancer registries from 1961 to 2005. For the present study we selected a cohort of visual artists from Finland, Iceland, Norway, and Sweden. Standardized incidence ratio (SIR) analyses were conducted with the cancer incidence rates for the entire national study populations used as reference rates. Results In male visual artists, there were statistically significant excesses in cancers of the tongue (SIR 2.91, 95% confidence interval 1.74–4.55), oral cavity (2.09, 1.26–3.27), pharynx (2.18, 1.45-–3.15), testis (1.91, 1.11–3.05), renal pelvis (2.48, 1.42–4.03) and bladder (1.33, 1.14–1.55). The risk was significantly decreased for cancers of the lip (0.45, 0.18-0.93) and stomach (0.65, 0.50–0.84). In female visual artists, the only significantly increased risk was observed for breast cancer (1.29, 1.13–1.48) and the only significantly decreased risk for stomach cancer (0.43, 0.17–0.88). The incidence of lung cancer was close to the population average in both sexes. Conclusions The non-elevated incidence of lung cancer suggests a similar prevalence of smoking between visual artists and the general population, while the elevated risk of cancers of mouth and pharynx among male visual artists is suggestive of more widespread alcohol drinking. The excess risk of urogenital cancers might be associated with exposure to solvents.

Cancer risk and temporal trends in people with HIV during a quarter of a century – a nationwide population-based matched cohort study

Background It is important to understand current trends in cancer risk among people living with HIV (PLWH) to improve outcomes and to commission and delivery appropriate services. Methods Nationwide, population-based, matched cohort study on all adult PLWH treated at Danish HIV health care centres since 1 January 1995 and a comparison cohort, randomly selected from the background population and matched on sex and date of birth. Results We included 6327 PLWH and 63,270 individuals in the comparison cohort − 74% were men and median age was 37 (interquartile range: 30–46). For both smoking related cancers, virological cancers and other cancers, incidence was substantially higher in the first year of observation for PLWH than for the remaining observation period. The risk of smoking related cancer remained stably increased throughout the observation period, whereas the relative risk of virological cancers decreased, especially in the first year of follow up. Finally, the risk of other cancers for PLWH decreased to a level below that of the background population during the study period. Conclusion The fact that the risk of other cancers was probably not higher among PLWH than in the comparison cohort is encouraging, as the excess risk of virological and smoking related cancers is potentially preventable by timely treatment of HIV and smoking cessation.

Assessing the health risks of coal-burning arsenic-induced skin damage: A 22-year follow-up study in Guizhou, China

Risk assessment of arsenic-induced skin damage has always received significant global attention. Theories derived from arsenic exposure in drinking water may not be applicable to the coal-burning type to arsenic-exposed area. Furthermore, very few studies have successfully determined the reference value of cumulative arsenic (CA) exposure that leads to specific skin lesions. In this study, we conducted a 22-year follow-up investigation to assess the risk of skin lesions and cancer resulting from long-term, multi-channel arsenic exposure from hazard identification, dose-response assessment, exposure assessment, and risk characterization. The results show that the arsenic exposure can significantly increase the prevalence of skin lesions. For each interquartile range increase of hair arsenic (HA) and CA, the risk of skin damage increased by 1.91 and 3.90 times, respectively. The lower confidence limit of the benchmark dose of HA of arsenic-induced various skin lesions ranged from 0.07 to 0.12 μg·g−1, and 932.57 to 1368.92 mg for CA. The chronic daily intake, lifetime average daily dose in the arsenic-exposed area after the comprehensive prevention and control measures have decreased significantly, but remained higher than the daily baseline level of 3.0 μg·kg−1·d−1. Even as recently as 2020, the hazard quotients and hazard index still exceeded 1, measuring 155.33 and 55.20, and the lifetime excess risk of skin cancer (2.80 × 10−3) remains significantly higher than the acceptable level of 10−6. Our study underscores the effectiveness of comprehensive prevention and control measures in managing high arsenic exposure in coal-burning arsenic poisoning areas. However, it is crucial to acknowledge that the risk of both non-carcinogenic and carcinogenic effects on the skin remains substantially higher than the acceptable level. We recommend setting reference limits for monitoring skin damage among individuals exposed to arsenic, with a recommended upper limit of 0.07 μg·g−1 for HA and a maximum acceptable level of 935.57 mg for CA.

Updated risk models for lung cancer due to radon exposure in the German Wismut cohort of uranium miners, 1946-2018.

UNSCEAR recently recommended that future research on the lung cancer risk at low radon exposures or exposure rates should focus on more contemporary uranium miners. For this purpose, risk models in the German Wismut cohort of uranium miners were updated extending the follow-up period by 5years to 1946-2018. The full cohort (n = 58,972) and specifically the 1960 + sub-cohort of miners first hired in 1960 or later (n = 26,764) were analyzed. The 1960 + sub-cohort is characterized by low protracted radon exposure of high quality of measurements. Internal Poisson regression was used to estimate the excess relative risk (ERR) for lung cancer per cumulative radon exposure in Working Level Months (WLM). Applying the BEIR VI exposure-age-concentration model, the ERR/100WLM was 2.50 (95% confidence interval (CI) 0.81; 4.18) and 6.92 (95% CI < 0; 16.59) among miners with attained age < 55years, time since exposure 5-14years, and annual exposure rates < 0.5WL in the full (n = 4329 lung cancer deaths) and in the 1960 + sub-cohort (n = 663 lung cancer deaths), respectively. Both ERR/WLM decreased with older attained ages, increasing time since exposure, and higher exposure rates. Findings of the 1960 + sub-cohort are in line with those from large pooled studies, and ERR/WLM are about two times higher than in the full Wismut cohort. Notably, 20-30years after closure of the Wismut mines in 1990, the estimated fraction of lung cancer deaths attributable to occupational radon exposure is still 26% in the full Wismut cohort and 19% in the 1960 + sub-cohort, respectively. This demonstrates the need for radiation protection against radon.

Radiological Safety Assessment of Agricultural Soil within the Bitumen Belt of Ondo State Nigeria, Using RESRAD-ONSITE and RESRAD-BIOTA Codes

Exploration and exploitation of bitumen can create radiation exposure pathways that must be considered in risk management scenarios. RESRAD-ONSITE and RESRAD-BIOTA developed by the US Department of Energy (US DOE) to assess contaminated sites, were used in the present study to predict the radiation dose and excess cancer risk associated with residual radioactive materials within Ondo State Bitumen Belt for the duration of 100 years, using site-specific parameters. The activity concentrations of 40K, 232Th and 238U in soil samples were determined by gamma-spectrometry and their average values were 35.85, 3.27 and 5.01 BqKg-1 respectively. While the estimated internal doses in biota due to 40K, 232Th and 238U were 7.54E-06, 3.03E-07 and 4.55E-08 Gy d−1 respectively for terrestrial animals, 6.69E-06, 3.68E-08 and 2.29E-08 Gy d−1 respectively for terrestrial plants, 6.49E-06, 5.88E-09 and 2.22E-08 08 Gy d−1 respectively for the Nigerian Dwarf Goat (NDG). The maximum total dose of 0.0229 mSvyr−1 was obtained at Agbabu at t = 30 years for an on-site resident farmer using the RESRAD-ONSITE Code, while the minimum total dose of 0.0014 was obtained at Araromi at t = 100 years. These values were by far lower than the National Research Council's acceptable limit of 0.25 mSvy-1. Likewise, the maximum Excess Cancer Risk (ECR) of 0.050 × 10−3 was obtained at Agbabu, while the lowest ECR value of 0.015 x 10-3 was shared by three communities: Omotosho (OMO), Akotogbo (AKG), and Ibekegbo (IKB). The observed low cancer risks in all the selected communities are of less human health concern since they are lower than the world safe value of 0.29 x 10-3. This implies that utilization of the studied soil for farming may not cause any immediate health hazard to the inhabitant but prolonged exposure might pose radiologically induced health challenges.

P25-11: The effect of the introduction of European Union drinking water standard on arsenic exposure and related lifetime excess cancer risk in Hungary – a population based estimation of public health and economic benefits

P25-11: The effect of the introduction of European Union drinking water standard on arsenic exposure and related lifetime excess cancer risk in Hungary – a population based estimation of public health and economic benefits

Characterization of the sources and health risks of polycyclic aromatic hydrocarbons in PM2.5 and their relationship with black carbon: A case study in northern Taiwan

Polycyclic aromatic hydrocarbons (PAHs) and black carbon (BC) often coexist in PM2.5 because both form during the incomplete combustion of organic matter. These compounds are regarded as hazardous air pollutants with potential health effects, including respiratory and cardiovascular effects. In this study, to evaluate the health risks of PAHs and BC at an urban site in northern Taiwan, 16 priority PAHs and BC, identified by the United States Environmental Protection Agency, were analyzed and quantified in PM2.5 to determine their concentrations, their relationship with each other, and their likely sources. The results indicated that the mean concentrations of total PAHs and BC were 0.91 ng m−3 and 0.97 μg m−3, respectively, with a significant positive correlation between them, indicating the same emission sources. The results also indicated that fossil fuel combustion and traffic emissions were primary contributors to PAHs, with wood and biomass combustion playing a less prominent role. Among these 16 priority PAHs, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[b]fluoranthene, and indeno[1,2,3-cd]pyrene served as major carcinogenic compounds, accounting for 89.0% of the total carcinogenic toxicity. Thus, the lifetime excess cancer risk resulting from PAH exposure was estimated as 8.03 × 10−6, indicating a potential carcinogenic risk to human health at the sampling site. Overall, this study highlights the need for future mitigation policies for traffic emissions and fossil fuel combustion for reducing the local emissions of BC and co-produced PAHs in northern Taiwan.

No Excess Cancer Risk among Veterinarians in Denmark, Finland, Iceland, Norway, and Sweden after the 1980s.

The cancer profile of veterinarians has received little research attention, despite the profession potentially being exposed to a wide range of known and suspected carcinogens. In this large-scale cohort study, we assessed cancer incidence in veterinarians in Denmark, Finland, Iceland, Norway, and Sweden, across more than 40 years (1961-2005). The cohort comprised 4708 veterinarians and 119,503 person-years at follow-up. The overall cancer incidence in veterinarians was close to the incidence in the total population in all countries and in all age groups. In male veterinarians, the standardized incidence ratios (SIR) in 1961-1990 were elevated for colon cancer (1.86, 95% confidence interval (CI) 1.39-2.44), prostate cancer (1.35, 95% CI 1.07-1.67), and especially skin melanoma (3.62, 95% CI 2.78-2.84), while there was no longer any statistically significant excess in the more recent follow-up period. Decreased SIRs were observed for lip cancer (0.11, 95% CI 0.00-0.62), laryngeal cancer (0.38, 95% CI 0.12-0.89), lung cancer (0.59, 95% CI 0.47-0.74), and stomach cancer (0.58, 95% CI 0.38-0.86), without a marked change in SIR over time. Non-significant excesses among male veterinarians were also observed in Hodgkin lymphoma (1961-1990 only), and leukaemia. This multi-country study indicates that there was an elevated incidence of several cancer types among male veterinarians before the 1990s but not after that. Some of the findings might rather be attributed to lifestyle factors and not directly to work conditions, but the excess risk of cancers of kidney and bladder, for example, might be related to work exposures.

Estimation of Health Risks Caused by Metals Contained in E-Cigarette Aerosol through Passive Vaping.

It is expected that secondary exposure to e-cigarette aerosol (passive vaping) will soon become an issue of public health. Passive vaping inhales e-cigarette aerosol containing similar harmful substances as active vaping. However, parallel studies on passive vaping are minimal. Therefore, there is a need for passive vaping-related health risk studies to assess the impact of vaping on public health. This research conducted a series of experiments in a room using a puffing machine and the Mobile Aerosol Lung Deposition Apparatus (MALDA) to study e-cigarette aerosol respiratory deposition through passive vaping. The experimental data acquired were applied to estimate the deposited mass and health risks caused by toxic metals contained in e-cigarette aerosol. Five popular e-cigarette products were used in this study to generate e-cigarette aerosol for deposition experiments. In addition, size-segregated e-cigarette aerosol samples were collected, and metal compositions in the e-cigarette aerosol were analyzed. Results obtained showed that estimated non-cancer risks were all acceptable, with hazard quotient and hazard index all less than 1.0. The calculated cancer risks were also found acceptable, with lifetime excess cancer risk generally less than 1E-6. Therefore, the e-cigarettes tested and the passive vaping exposure scenarios studied do not seem to induce any potential for metal-related respiratory health effects.

Studies of dose distribution to Lung and Stomach and Estimation of Second Cancer Risk due to Outfeld Dose in Radiotherapy with 60Co Teletherapy Beam

A critical component of the radiation regimen for treating cancer patients is the precise dose delivery to the treatment organ while minimizing the dose to the healthy tissue. This study aims to evaluate in-field organ dose and dose distribution outside the target organs to estimate the excess lifetime risk of second cancer. The study was carried out with a male Alderson Rando Phantom. 20 sets of thermoluminescence dosimeters (MTS-100) were used in this study. The in-field organs absorbed dose was measured by inserting TLDs at different geometrical depths of the left lung, right lung, and stomach, and for peripheral organs skin dose TLDs were placed at the surface of the corresponding organs. Target organs were irradiated at 100 cGy and 200 cGy by a 60Co teletherapy unit, and irradiated TLDs were read out by a RE-2000 TLD reader. For precise dose delivery to the cancerous organs by 60Co teletherapy, the depth dose correction factor for lung cancer treatment is 0.8667 ± 0.01, and for the stomach is 0.7856 ± 0.017. In the case of the treatment for the lung and stomach, the closest organs received significant doses compared to the other distant organs. Thus, the risk of second cancer due to the peripheral dose is obtained. The stomach is at the highest risk when the lung is the target and the liver is at the highest risk when the stomach is the targeted organ.

Arsenic Levels in Soil and Rice and Health Risk Assessment via Rice Consumption in Industrial Areas of East Java, Indonesia

Industrial use of arsenic can potentially cause environmental problems in water, soil, and air. Arsenic is one of heavy metals that is highly toxic and carcinogenic. Arsenic contamination in the environment is harmful to human health because it can enter the body through the food chain. This study determined the concentration of arsenic in soil and rice and its impact on human health risks. Sampling was carried out in several East Java industrial cities or districts, for instance, Gresik, Mojokerto, Sidoarjo, Nganjuk, Ponorogo, and Surabaya. The measurement of arsenic in soil was done using Energy Dispersive X-Ray fluorescence (EDXRF), while the measurement of arsenic in rice was done by Total X-Ray Fluorescence (TXRF). The results showed that arsenic concentration in several areas of East Java has varying levels. The concentration of arsenic in soil was highest in Gresik (13,786 mg/kg). The highest arsenic concentration in rice was found in Mojokerto (0.154 mg/kg). The results of risk assessment in this study showed that the Hazard Quotient (HQ) value was &gt;1 and the Excess Cancer Risk (ECR) was &gt;10-4 in all areas at the age of children &lt;2 years. Health risk assessment of adults showed HQ&gt;1 and ECR&gt;10-4 in several areas of East Java. This indicates that consumption of rice contaminated with arsenic has the potential to pose non-carcinogenic and carcinogenic health risks.

The underestimated impact of excess body weight on colorectal cancer risk: Evidence from the UK Biobank cohort.

The association between excess weight and colorectal cancer (CRC) risk may have been underestimated due to potential weight loss during pre-clinical sojourn time of CRC. We aimed to investigate this association and the corresponding population attributable fraction (PAF), accounting for prediagnostic weight loss. Data from the UK Biobank prospective cohort were used. Multivariable adjusted hazard ratios (HR) and their 95% confidence intervals (CI) for various periods of follow-up and the corresponding PAF of excess weight were calculated. During a median of 10.0 years of follow-up, of 453,049 participants, 4794 developed CRC. The excess weight-CRC association became substantially stronger with including increasing lengths of follow-up in the analyses and further excluding the initial years of follow-up. HRs (95% CIs) for overweight and obesity were 1.06 (0.97-1.16) and 1.14 (1.03-1.26) after 7 years of follow-up, 1.13 (1.05-1.21) and 1.23 (1.14-1.33) when including complete follow-up length, and 1.26 (1.12-1.43) and 1.42 (1.24-1.63) when excluding the initial 7 years of follow-up. The corresponding PAFs of excess weight were estimated as 6.8%, 11.3%, and 19.0%, respectively. Comprehensive consideration of the potential effect of prediagnostic weight loss discloses a much stronger impact of excess body weight on CRC risk than previously assumed.

Spatial distributions of PM10-bound metal elements in the central part of western Taiwan and their potential emission sources and the carcinogenic health risks.

This study aimed to investigate the spatial distribution of metal elements in PM10 and their potential sources and associated health risks over a period of two years in eight locations in the central part of western Taiwan. The study revealed that the mass concentration of PM10 and the total mass concentration of 20 metal elements in PM10 were 39.0 μg m-3 and 4.74 μg m-3, respectively, with total metal elements accounting for approximately 13.0% of PM10. Of the total metal elements, 95.6% were crustal elements (Al, Ca, Fe, K, Mg, and Na), with trace elements (As, Ba, Cd, Cr, Co, Cu, Ga, Mn, Ni, Pb, Sb, Se, V, and Zn) contributing only 4.4%. Spatially, the inland areas exhibited higher PM10 concentrations due to lee-side topography and low wind speeds. In contrast, the coastal regions exhibited higher total metal concentrations because of the dominance of crustal elements from sea salt and crustal soil. Four primary sources of metal elements in PM10 were identified as sea salt (58%), re-suspended dust (32%), vehicle emissions and waste incineration (8%), and industrial emissions and power plants (2%). The positive matrix factorization (PMF) analysis results indicated that natural sources like sea salt and road dust contributed up to 90% of the total metal elements in PM10, while only 10% was attributed to human activities. The excess cancer risks (ECRs) associated with As, Co, and Cr(VI) were greater than 1 × 10-6, and the total ECR was 6.42 × 10-5. Although only 10% of total metal elements in PM10 came from human activities, they contributed to 82% of the total ECR.