Lung cancer and occupational exposures other than cotton dust and endotoxin among women textile workers in Shanghai, China

Unlocking the secrets: Volatile Organic Compounds (VOCs) and their devastating effects on lung cancer

Lung cancer (LCs) is still a serious health problem globally, with many incidences attributed to environmental triggers such as Volatile Organic Compounds (VOCs). VOCs are a broad class of compounds that can be released via various sources, including industrial operations, automobile emissions, and indoor air pollution. VOC exposure has been linked to an elevated risk of lung cancer via multiple routes. These chemicals can be chemically converted into hazardous intermediate molecules, resulting in DNA damage and genetic alterations. VOCs can also cause oxidative stress, inflammation, and a breakdown in the cellular protective antioxidant framework, all of which contribute to the growth of lung cancer. Moreover, VOCs have been reported to alter critical biological reactions such as cell growth, apoptosis, and angiogenesis, leading to tumor development and metastasis. Epidemiological investigations have found a link between certain VOCs and a higher probability of LCs. Benzene, formaldehyde, and polycyclic aromatic hydrocarbons (PAHs) are some of the most well-researched VOCs, with comprehensive data confirming their cancer-causing potential. Nevertheless, the possible health concerns linked with many more VOCs and their combined use remain unknown, necessitating further research. Identifying the toxicological consequences of VOCs in LCs is critical for establishing focused preventative tactics and therapeutic strategies. Better legislation and monitoring mechanisms can limit VOC contamination in occupational and environmental contexts, possibly reducing the prevalence of LCs. Developing VOC exposure indicators and analyzing their associations with genetic susceptibility characteristics may also aid in early identification and targeted therapies.

Micro(nano)plastics in the Human Body: Sources, Occurrences, Fates, and Health Risks

The increasing global attention on micro(nano)plastics (MNPs) is a result of their ubiquity in the water, air, soil, and biosphere, exposing humans to MNPs on a daily basis and threatening human health. However, crucial data on MNPs in the human body, including the sources, occurrences, behaviors, and health risks, are limited, which greatly impedes any systematic assessment of their impact on the human body. To further understand the effects of MNPs on the human body, we must identify existing knowledge gaps that need to be immediately addressed and provide potential solutions to these issues. Herein, we examined the current literature on the sources, occurrences, and behaviors of MNPs in the human body as well as their potential health risks. Furthermore, we identified key knowledge gaps that must be resolved to comprehensively assess the effects of MNPs on human health. Additionally, we addressed that the complexity of MNPs and the lack of efficient analytical methods are the main barriers impeding current investigations on MNPs in the human body, necessitating the development of a standard and unified analytical method. Finally, we highlighted the need for interdisciplinary studies from environmental, biological, medical, chemical, computer, and material scientists to fill these knowledge gaps and drive further research. Considering the inevitability and daily occurrence of human exposure to MNPs, more studies are urgently required to enhance our understanding of their potential negative effects on human health.

Worker studies suggest unique liver carcinogenicity potential of polyvinyl chloride microplastics

BACKGROUND

Plastic debris pervades our environment. Some breaks down into microplastics (MPs) that can enter and distribute in living organisms causing effects in multiple target organs. MPs have been demonstrated to harm animals through environmental exposure. Laboratory animal studies are still insufficient to evaluate human impact. And while MPs have been found in human tissues, the health effects at environmental exposure levels are unclear.

AIM

We reviewed and summarized existing evidence on health effects from occupational exposure to MPs. Additionally, the diverse effects documented for workers were organized by MP type and associated co-contaminants. Evidence of the unique effects of polyvinyl chloride (PVC) on liver was then highlighted.

METHODS

We conducted two stepwise online literature reviews of publications focused on the health risks associated with occupational MP exposures. This information was supplemented with findings from animal studies.

RESULTS

Our analysis focused on 34 published studies on occupational health effects from MP exposure with half involving exposure to PVC and the other half a variety of other MPs to compare. Liver effects following PVC exposure were reported for workers. While PVC exposure causes liver toxicity and increases the risk of liver cancers, including angiosarcomas and hepatocellular carcinomas, the carcinogenic effects of work-related exposure to other MPs, such as polystyrene and polyethylene, are not well understood.

CONCLUSION

The data supporting liver toxicity are strongest for PVC exposure. Overall, the evidence of liver toxicity from occupational exposure to MPs other than PVC is lacking. The PVC worker data summarized here can be useful in assisting clinicians evaluating exposure histories from PVC exposure and designing future cell, animal, and population exposure-effect research studies.

Characteristics and health risks of population exposure to phthalates via the use of face towels

The production of face towels is growing at an annual rate of about 4% in China, reaching 1.13 million tons by 2021. Phthalates (PAEs) are widely used in textiles, and face towels, as an important household textile, may expose people to PAEs via the skin, further leading to health risks. We collected new face towels and analyzed the distribution characterization of PAEs in them. The changes of PAEs were explored in a face towel use experiment and a simulated laundry experiment. Based on the use of face towels by 24 volunteers, we calculated the estimated daily intake (EDI) and comprehensively assessed the hazard quotient (HQ), hazard index (HI), and dermal cancer risk (DCR) of PAEs exposure in the population. PAEs were present in new face towels at total concentrations of <MDL-2388 ng/g, with a median of 173.2 ng/g, which was a lower contamination level compared with other textiles. PAE contents in used face towels were significantly higher than in new face towels. The concentrations of PAEs in coral velvet were significantly higher than those in cotton. Water washing removed some PAEs, while detergent washing increased the PAE content on face towels. Gender, weight, use time, and material were the main factors affecting EDI. The HQ and HI were less than 1, which proved PAEs had no significant non-carcinogenic health risks. Among the five target PAEs studied, DEHP was the only carcinogenic PAE and may cause potential health risks after long-term exposure. Therefore, we should pay more attention to DEHP.

The Carcinogenic Effects of Formaldehyde Occupational Exposure: A Systematic Review

BACKGROUND

Formaldehyde, classified as a carcinogen in 2004, as of today is widely used in many work activities. From its classification, further studies were performed to evaluate its carcinogenicity. The aim of the systematic review is to update the evidence on occupational exposure to formaldehyde and cancer onset.

METHODS

The review, in accordance with the PRISMA statement, includes articles in English reporting original results of studies conducted on workers exposed to formaldehyde, considering all types of cancer, published from 1 January 2000 to 30 July 2021 and selected from the Pubmed and Scopus databases. The studies' quality was assessed by the Newcastle-Ottawa Scale.

RESULTS

A total of 21 articles were included, conducted in different European, American, and Asian countries. The most investigated occupational areas are those characterized by a deliberate use of formaldehyde. Some studies evaluated all types of cancer, whereas others focused on specific sites such as thyroid and respiratory, lymphohematopoietic, or central nervous systems. The results showed weak associations with lung cancer, nasopharyngeal cancer, leukemia, and non-Hodgkin's lymphoma.

CONCLUSIONS

The results demonstrate the need for further original studies carried out on representative samples of workers exposed to measured levels of FA. These studies should be designed to reduce the bias due to co-exposure to other carcinogens.

Role of occupational exposures in lung cancer risk among women

OBJECTIVES

To explore possible associations between selected occupational agents and lung cancer risk among women.

METHODS

A population-based case-control study on lung cancer was conducted from 1996 to 2001 in Montreal, Canada. Cases were individuals diagnosed with incident lung cancer and population controls were randomly selected from electoral lists and frequency-matched to age and sex distributions of cases. Questionnaires on lifetime occupational history, smoking and demographic characteristics were collected during in-person interviews. As part of a comprehensive exposure assessment protocol, experts reviewed each subject's work history and assessed exposure to many agents. The current analysis, restricted to working women in the study, includes 361 cases and 521 controls. We examined the association between lung cancer and each of 22 occupational exposures, chosen because of their relatively high prevalences among these women. Each exposure was analysed in a separate multivariate logistic regression model, adjusted for smoking and other selected covariates.

RESULTS

There were few elevated OR estimates between lung cancer and any of the agents, and none were statistically significant, although the limited numbers of exposed women engendered wide CIs.

CONCLUSIONS

There was little evidence to suggest that women in this population had experienced excess risks of lung cancer as a result of their work exposures. However, the wide CIs preclude any strong inferences in this regard.

Occupational exposure to formaldehyde and risk of lung cancer: A systematic review and meta-analysis

BACKGROUND

Formaldehyde exposure is associated with nasopharyngeal cancer and leukemia. Previously-described links between formaldehyde exposure and lung cancer have been weak and inconsistent. We performed a systematic review and meta-analysis to evaluate quantitatively the association between formaldehyde exposure and lung cancer.

METHODS

We searched for articles on occupational formaldehyde exposure and lung cancer in PubMed, EMBASE, Web of Science, and CINAHL databases. In total, 32 articles were selected and 31 studies were included in a meta-analysis. Subgroup analyses and quality assessments were also performed.

RESULTS

The risk of lung cancer among workers exposed to formaldehyde was not significantly increased, with an overall pooled risk estimate of 1.04 (95% confidence interval [CI], 0.97-1.12). The pooled risk estimate of lung cancer was increased when higher exposure studies were considered (1.19; 95% CI, 0.96-1.46). More statistically robust results were obtained when high quality (1.13; 95% CI, 1.08-1.19) and recent (1.13; 95% CI, 1.07-1.19) studies were used in deriving pooled risk estimates.

CONCLUSIONS

No significant increase in the risk of lung cancer was evident in the overall pooled risk estimate; even in higher formaldehyde exposure groups. Our findings do not provide strong evidence in favor of formaldehyde as a risk factor for lung cancer. However, since risk estimates were significantly increased for high-quality and recent studies, the possibility that exposure to formaldehyde can increase the risk of lung cancer might still be considered.

Cotton dust exposure and risk of lung cancer: A meta-analysis of observational studies

Findings on the association between cotton dust exposure and lung cancer risk in epidemiologic studies have been inconsistent. Therefore, we conducted a meta-analysis of data from observational studies to quantify this association.PubMed, EMBASE, and the Cochrane library databases were searched for observational studies with data on cotton dust exposure and lung cancer risk. Studies that reported adjusted relative risks (RRs) with 95% confidence intervals (CIs) of lung cancer associated with cotton dust exposure were included. Subgroup analyses were conducted according to key characteristics.Fifteen studies involving a total of 73,812 individuals were included in the meta-analysis. Combining estimates from all the 15 observational studies, cotton dust exposure was associated with a decreased risk of lung cancer (combined RR, 0.78; 95% CI, 0.66-0.91; P = .002). Pooled estimates of multivariate RRs by gender were 0.71 (95% CI, 0.58-0.88; P = .001) among males, based on 7 studies, and 0.77 (95% CI, 0.67-0.89; P < .001) among females, based on 9 studies. Further analyses examining the influence of a single study on the results by omitting a study at each turn yielded a range of RR from 0.74 to 0.82.Our meta-analysis indicates that cotton dust exposure is associated with a decreased risk of lung cancer.

Occupational exposure to textile dust and lung cancer risk: Results from the ICARE Study

BACKGROUND

To investigate the association of lung cancer with occupational exposure to textile dust and specifically to cotton dust in the population-based case-control study ICARE.

METHODS

Lifelong occupational history of 2926 cases and 3555 controls was collected using standardized questionnaires, with specific questions for textile dust exposure. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using unconditional logistic regression models controlling for confounding factors including smoking and asbestos exposure.

RESULTS

An inverse association between textile dust exposure and lung cancer was found among workers exposed ≥5% of their work time (OR = 0.80, 95%CI = 0.58-1.09), more pronounced for distant exposures (40+ years; up to a 56% reduced risk, statistically significant). The OR of lung cancer was significantly decreased among workers exposed to cotton fibers (OR = 0.70, 95%CI = 0.48-0.97).

CONCLUSIONS

Our results provide some evidence of a decreased risk of lung cancer associated with exposure to textile dust, particularly cotton.

Spatial Analysis of Regional Factors and Lung Cancer Mortality in China, 1973-2013

Background: China's lung cancer crude death rate has increased 6.9-fold from 1973 to 2014. During this time, the country experienced extremely rapid economic growth and social change. It is important to understand the effects of risk factors on lung cancer mortality (LCM) for better allocation of limited resources of cancer prevention and control in China.Methods: Using three nationwide mortality surveys from 1973 to 2005, Global Health Data Exchange data in 2013, three nationwide smoking surveys from 1984 to 2013, four population censuses from 1964 to 2000, and other datasets, we have compiled datasets and developed spatial random effect models to assess the association of various area-level-contributing factors on LCM. Spatial scan statistics are used to detect high-risk clusters of LCM.Results: LCM is higher in urban and more industrialized areas (RR = 1.17) compared with those in rural areas. The level of industrial development's effect is higher for men, which accounts for about 70% of all LCM. Smoking is positively associated with regional variation of LCM rates, and the effect is higher for women than for men.Conclusions: The geographic pattern of high LCM in China is different from that of Western countries. LCM is positively associated with higher socioeconomic status, with more urbanized areas at a higher level of industrial development.Impact: There is a need to further explore additional risk in the high-risk clusters. The study is about China, but this situation may happen in other countries experiencing rapid industrialization and other developing countries. Cancer Epidemiol Biomarkers Prev; 26(4); 569-77. ©2017 AACRSee all the articles in this CEBP Focus section, "Geospatial Approaches to Cancer Control and Population Sciences."

Textile industry and occupational cancer

BACKGROUND AND SUMMARY

Thousands of workers are engaged in textile industry worldwide. Textile industry involves the use of different kinds of dyes which are known to possess carcinogenic properties. Solvents used in these industries are also associated with different health related hazards including cancer. In previous studies on textile and iron industries, the authors have reported genotoxicity among them and observed occurrence of cancer deaths among textile industry workers. Thus, an attempt has been made to compile the studies on the prevalence of different types of cancers among textile industry workers.

LITERATURE SEARCH

A wide literature search has been done for compiling the present paper. Papers on cancer occurrence among textile industry workers have been taken from 1976 to 2015. A variety of textile dyes and solvents, many of them being carcinogenic, are being used worldwide in the textile industry. The textile industry workers are therefore, in continuous exposure to these dyes, solvents, fibre dusts and various other toxic chemicals. The present study evaluates the potential of different chemicals and physical factors to be carcinogenic agents among occupationally exposed workers by going through various available reports and researches. Papers were collected using different databases and a number of studies report the association of textile industry and different types of cancer including lung, bladder, colorectal and breast cancer. After going through the available reports, it can be concluded that workers under varied job categories in textile industries are at a higher risk of developing cancer as various chemicals used in the textile industry are toxic and can act as potential health risk in inducing cancer among them. Assessing the cancer risk at different job levels in textile industries may be found useful in assessing the overall risk to the workers and formulating the future cancer preventive strategies.

Night shift work and lung cancer risk among female textile workers in Shanghai, China

In 2007, the International Agency for Research on Cancer classified shift work that involves circadian disruption as a probable human carcinogen. Suppression of the anti-neoplastic hormone, melatonin, is a presumed mechanism of action. We conducted a case-cohort study nested within a cohort of 267,400 female textile workers in Shanghai, China. Newly diagnosed lung cancer cases (n = 1451) identified during the study period (1989-2006) were compared with an age-stratified subcohort (n = 3040). Adjusting for age, smoking, parity, and endotoxin exposure, relative risks [hazard ratios (HRs)] were estimated by Cox regression modeling to assess associations with cumulative years and nights of rotating shift work. Results did not consistently reveal any increased risk of lung cancer among rotating shift work or statistically significant trends for both cumulative years (HR 0.82, 95% CI 0.66 to 1.02; P(trend) = 0.294) and nights (HR 0.81, 95% CI 0.65 to 1.00; P(trend) = 0.415). Further analyses imposing 10- and 20-year lag times for disease latency also revealed similar results. Contrary to the initial hypothesis, rotating nighttime shift work appears to be associated with a relatively reduced lung cancer risk although the magnitude of the effect was modest and not statistically significant.

Urinary concentrations of metabolites of pyrethroid insecticides in textile workers, Eastern China

Pyrethroid insecticides have been applied in the production of cotton, wool and textile. In order to examine whether textile workers are exposed to pyrethroid insecticides, we recruited 50 textile workers in two textile plants in Eastern China. Their urine samples were collected for the measurement of pyrethroid metabolites: cis- and trans-isomers of 2,2-dichlorovinyl-2,2-dimethylcyclopropane-1-carboxylic acid (cis-Cl2CA and trans-Cl2CA) and 3-phenoxybenzoic acid (3-PBA). Our results showed that textile workers were exposed to high levels of pyrethroid insecticides. cis-Cl2CA and 3-PBA were dominant metabolites with concentrations of 0.17-261μg/L, while concentrations of trans-Cl2CA were in the range of 0.26-11μg/L. Levels of three metabolites were in a descending order: cis-Cl2CA, 3-PBA, and trans-Cl2CA. Levels of the metabolites were associated with ages and job responsibilities of textile workers. Sewing workers, cutting workers, machine operators, reorganizers, and older workers were more likely in contact with pyrethroid insecticides in the textile production. trans- to cis-Cl2CA ratios might indicate that exposure of textile workers was via dermal absorption and inhalation.

Mortality from solid tumors among workers in formaldehyde industries: an update of the NCI cohort

BACKGROUND

Formaldehyde, a widely used chemical, is considered a human carcinogen.

METHODS

We extended follow-up of the largest industrial cohort of workers in formaldehyde industries (n = 25,619) by 10 years through 2004. Standardized mortality ratios (SMRs) and rate ratios (RRs) were calculated for deaths from solid tumors using quantitative formaldehyde exposure estimates.

RESULTS

During 998,239 person-years, 13,951 deaths occurred. With one additional death, previously observed excesses for nasopharyngeal cancer (n = 10) persisted for peak, average intensity and cumulative exposure; RRs in the highest exposure categories were 7.66 (95% CI: 0.94, 62.34), P-trend = 0.005, 11.54 (95% CI: 1.38, 96.81), P-trend = 0.09, and 2.94 (95% CI: 0.65, 13.28), P-trend = 0.06, respectively. For all cancer, solid tumors and lung cancer, SMRs among exposed workers were elevated, but internal analyses revealed no positive associations with formaldehyde exposure.

CONCLUSIONS

Consistent with previous analyses of this cohort, this update continues to suggest a link between formaldehyde exposure and nasopharyngeal cancer.

Reproductive factors and risk of lung cancer in female textile workers in Shanghai, China

PURPOSE

Hormonal factors may play a role in the development of lung cancer in women. This study examined the relationship between lung cancer and reproductive factors in a large cohort of women, most of whom never smoked (97%).

METHODS

A cohort of 267,400 female textile workers in Shanghai, China, enrolled in a trial of breast self-examination provided information on reproductive history, demographical factors, and cigarette smoking at enrollment in 1989-91. The cohort was followed until July of 2000 for incidence of lung cancer; 824 cases were identified. Hazard ratios (HR) and 95% confidence intervals (CI) associated with selected reproductive factors were calculated using Cox proportional hazards modeling, adjusting for smoking, age, and also parity when relevant.

RESULTS

Nulliparous women were at increased risk compared to parous women (HR = 1.33, 95% CI 1.00-1.77). Women who had gone through menopause at baseline were at increased risk compared to women of the same age who were still menstruating. Risk was higher in women with a surgical menopause (HR = 1.64, 95% CI 0.96-2.79) than in those with a natural menopause (HR = 1.35, 95% CI 0.84-2.18), and risk was highest in those postmenopausal women with a hysterectomy and bilateral oophorectomy at baseline (HR = 1.39, 95% CI 0.96-2.00), although the risk estimates were not statistically significant.

CONCLUSIONS

These results support experimental data that demonstrate a biological role for hormones in lung carcinogenesis.

Dust is in the air: effects of occupational exposure to mineral dust on lung function in a 9-year study

BACKGROUND

Occupational mineral dust exposure is a well-known risk factor for numerous respiratory and systemic diseases. The aim of the present longitudinal study was to assess the influence of work-associated dust exposure on spirometric results. Furthermore, the impact of implementation of stricter limit values for occupational contact with quartz dust on lung function was evaluated.

METHODS

Anthropometric data (age, gender, BMI), smoking behavior, and lung function parameters (FVC, FEV1, MEF50) from 7,204 medical examinations of 3,229 female and male workers during the years 2002-2010 were examined following Austrian standards for occupational medicine and the guidelines of the European Respiratory Society. Analysis of data was performed using models of multiple linear regression.

RESULTS

Lung function decrease over time was associated with smoking habits and duration of occupational dust exposure. Specifically, occupational quartz exposure negatively influenced the annual lung function parameters (FVC, -6.68 ml; FEV1, -6.71 ml; and MEF50, -16.15 ml/s, all p < 0.001). Thus, an overadditive effect of smoking and work-related contact with quartz was found regarding decline in MEF50 (p < 0.05). Implementation of stricter occupational limit values for dust exposure resulted in a highly significant deceleration of the annual decrease in respiratory function (p = 0.001).

CONCLUSIONS

Individual smoking habits and occupational dust exposure had a negative impact on lung function. To reduce the risk of loss of respiratory capacity, smoking cessation is especially recommended to workers exposed to quartz dust. Moreover, stricter limit values could prevent chronic occupational damage to the respiratory system.

Recent trend in risk assessment of formaldehyde exposures from indoor air

Studies about formaldehyde (FA) published since the guideline of 0.1 mg/m(3) by the World Health Organization (WHO) in 2010 have been evaluated; critical effects were eye and nasal (portal-of-entry) irritation. Also, it was considered to prevent long-term effects, including all types of cancer. The majority of the recent toxicokinetic studies showed no exposure-dependent FA-DNA adducts outside the portal-of-entry area and FA-DNA adducts at distant sites were due to endogenously generated FA. The no-observed-adverse-effect level for sensory irritation was 0.5 ppm and recently reconfirmed in hypo- and hypersensitive individuals. Investigation of the relationship between FA exposure and asthma or other airway effects in children showed no convincing association. In rats, repeated exposures showed no point mutation in the p53 and K-Ras genes at ≤15 ppm neither increased cell proliferation, histopathological changes and changes in gene expression at 0.7 ppm. Repeated controlled exposures (0.5 ppm with peaks at 1 ppm) did not increase micronucleus formation in human buccal cells or nasal tissue (0.7 ppm) or in vivo genotoxicity in peripheral blood lymphocytes (0.7 ppm), but higher occupational exposures were associated with genotoxicity in buccal cells and cultivated peripheral blood lymphocytes. It is still valid that exposures not inducing nasal squamous cell carcinoma in rats will not induce nasopharyngeal cancer or lymphohematopoietic malignancies in humans. Reproductive and developmental toxicity are not considered relevant in the absence of sensory irritation. In conclusion, the WHO guideline has been strengthened.