The effect of occupational exposure to solar ultraviolet radiation on malignant skin melanoma and non- melanoma skin cancer: a systematic review and meta-analysis from the WHO/ILO Joint Estimates of the Work-related Burden of Disease and Injury

A systematic review and meta-analysis of studies were conducted reporting on the association between occupational exposure to solar ultraviolet radiation (UVR) and both malignant skin melanoma (melanoma) and non-melanoma skin cancer (NMSC), with the aim of enabling the estimation of the numbers of deaths and disability-adjusted life years from melanoma and NMSC attributable to occupational exposure to solar UVR, for the development of the World Health Organization (WHO)/International Labour Organization (ILO) Joint Estimates of the Work-related Burden of Disease and Injury (WHO/ILO Joint Estimates). A protocol was developed and published, applying the Navigation Guide as an organizing systematic review framework where feasible. Electronic bibliographic databases were searched for potentially relevant records; electronic grey literature databases and organizational websites were also searched, reference lists of previous systematic reviews and included study records were hand-searched, and additional experts were consulted. Randomized controlled trials and cohort, case–control and other non-randomized studies were included that estimated the effect of any occupational exposure to solar UVR, compared with no occupational exposure to solar UVR, on melanoma (excluding melanoma of the lip or eye) or NMSC prevalence, incidence or mortality. At least two reviewers independently screened titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage. Adjusted relative risks were combined using random-effects meta-analysis. Two or more reviewers assessed the risk of bias, quality of evidence and strength of evidence. Fifty-three (48 case–control, three case–case and two cohort) eligible studies were found, published in 62 study records, including over 457 000 participants in 26 countries of three WHO regions (Region of the Americas, European Region and Western Pacific Region), reporting on the effect on melanoma or NMSC incidence or mortality. No studies on the prevalence of melanoma or NMSC were found. In most studies, exposure was self-reported in questionnaires during interviews and the health outcome was assessed via physician diagnosis based on biopsy and histopathological confirmation. The risk of bias of the body of evidence was judged to be generally “probably low”, although there were some concerns regarding risks of exposure misclassification bias, detection bias and confounding. The main meta-analyses of relevant case–control studies revealed a relative risk (RR) of melanoma and NMSC incidence of 1.45 (95% confidence interval (CI): 1.08–1.94; I2 = 81%) and 1.60 (95% CI: 1.21–2.11; I2 = 91%), respectively. No statistically significant differences in risk of melanoma and NMSC incidence were found when conducting subgroup analyses by WHO region, and no differences in risk of NMSC incidence in a subgroup analysis by sex. However, in a subgroup analysis by NMSC subtype, the increased risk of basal cell carcinoma (RR: 1.50; 95% CI: 1.10–2.04; 15 studies) was probably lower (P = 0.05 for subgroup differences) than the increased risk for squamous cell carcinoma (RR: 2.42; 95% CI: 1.66–3.53; 6 studies). The sensitivity analyses found that effect estimates of NMSC incidence were significantly higher in studies with any risk of bias domain rated as “high” or “probably high” compared with studies with only a “low” or “probably low” risk of bias, and in studies not reporting the health outcome by International Statistical Classification of Diseases and Related Health Problems (ICD) code compared with the two studies reporting ICD codes. The quality of available evidence of the effect of any occupational exposure to solar UVR on melanoma incidence and mortality and on NMSC mortality was rated as “low”, and the quality of evidence for NMSC incidence was rated as “moderate”. The strength of the existing bodies of evidence reporting on occupational exposure to solar UVR was judged as “inadequate evidence for harmfulness” for melanoma mortality and NMSC mortality. For the health outcome of melanoma incidence, the strength of evidence was judged as “limited evidence for harmfulness”, that is, a positive relationship was observed between exposure and outcome where chance, bias and confounding cannot be ruled out with reasonable confidence. For the health outcome of NMSC incidence, the strength of evidence was judged as “sufficient evidence of harmfulness”, that is, a positive relationship is observed between exposure and outcome where chance, bias and confounding can be ruled out with reasonable confidence. The 2009 International Agency for Research on Cancer classification of solar UVR as a Group 1 carcinogen that causes cutaneous melanoma and NMSC is a compelling attribute for the strength of evidence on occupational exposure to solar UVR and skin cancer incidence. Producing estimates for the burden of NMSC attributable to occupational exposure to solar UVR appears evidence-based (while acknowledging the limitations of the bodies of evidence), and the pooled effect estimates can be used as input data for the WHO/ILO Joint Estimates

Cancer Incidence and Mortality among Petroleum Industry Workers and Residents Living in Oil Producing Communities: A Systematic Review and Meta-Analysis

Petroleum extraction and refining are major sources of various occupational exposures and of air pollution and may therefore contribute to the global cancer burden. This systematic review and meta-analysis is aimed at evaluating the cancer risk in petroleum-exposed workers and in residents living near petroleum facilities. Relevant studies were identified and retrieved through PubMed and Web of Science databases. Summary effect size (ES) and 95% confidence intervals (CI) were analysed using random effect models, and heterogeneity across studies was assessed (I2). Overall, petroleum industry work was associated with an increased risk of mesothelioma (ES = 2.09, CI: 1.58–2.76), skin melanoma (ES = 1.34, CI: 1.06–1.70 multiple myeloma (ES =1.81, CI: 1.28–2.55), and cancers of the prostate (ES = 1.13, Cl: 1.05–1.22) and urinary bladder (ES = 1.25, CI: 1.09–1.43) and a decreased risk of cancers of the esophagus, stomach, colon, rectum, and pancreas. Offshore petroleum work was associated with an increased risk of lung cancer (ES = 1.20; 95% CI: 1.03–1.39) and leukemia (ES = 1.47; 95% CI: 1.12–1.92) in stratified analysis. Residential proximity to petroleum facilities was associated with childhood leukemia (ES = 1.90, CI: 1.34–2.70). Very few studies examined specific exposures among petroleum industry workers or residents living in oil producing communities. The present review warrants further studies on specific exposure levels and pathways among petroleum-exposed workers and residents living near petroleum facilities

Environmental Risk Factors for Childhood Acute Lymphoblastic Leukemia: An Umbrella Review

Leukemia is the most common type of cancer among children and adolescents worldwide. The aim of this umbrella review was (1) to provide a synthesis of the environmental risk factors for the onset of childhood acute lymphoblastic leukemia (ALL) by exposure window, (2) evaluate their strength of evidence and magnitude of risk, and as an example (3) estimate the prevalence in the German population, which determines the relevance at the population level. Relevant systematic reviews and pooled analyses were identified and retrieved through PubMed, Web of Science databases and lists of references. Only two risk factors (low doses of ionizing radiation in early childhood and general pesticide exposure during maternal preconception/pregnancy) were convincingly associated with childhood ALL. Other risk factors including extremely low frequency electromagnetic field (ELF-MF), living in proximity to nuclear facilities, petroleum, benzene, solvent, and domestic paint exposure during early childhood, all showed some level of evidence of association. Maternal consumption of coffee (high consumption/>2 cups/day) and cola (high consumption) during pregnancy, paternal smoking during the pregnancy of the index child, maternal intake of fertility treatment, high birth weight (≥4000 g) and caesarean delivery were also found to have some level of evidence of association. Maternal folic acid and vitamins intake, breastfeeding (≥6 months) and day-care attendance, were inversely associated with childhood ALL with some evidence. The results of this umbrella review should be interpreted with caution; as the evidence stems almost exclusively from case-control studies, where selection and recall bias are potential concerns, and whether the empirically observed association reflect causal relationships remains an open question. Hence, improved exposure assessment methods including accurate and reliable measurement, probing questions and better interview techniques are required to establish causative risk factors of childhood leukemia, which is needed for the ultimate goal of primary prevention

Histopathology of the Liver Following Administration of Artesunate in Adult Wistar Rats

Summary In must of the developing countries especially in Africa antimalaria drugs are taken regularly either to treat or prevent malaria. The rats were randomly divided into 3 groups of 5 each and tested as follows: - Group O- control (water), Group A – 2mg/kg and Group B - 6mg/kg. The animals were sacrificed after the 7th day. There was no mortality caused by the drug but dizziness in the animals. In the group administered with 2mg/kg of oral artesunate where was no form of distortion in the tissue architecture of the liver, but in the group administered with 6mg/kg of artesunate, artesunate caused sinusoidal congestion, infiltration of inflammatory cells and there was loss of tissue architecture. Drugs are produce to combat illnesses but may turn out be harmful when administered wrongly. In must of the developing countries especially in Africa antimalaria drugs are taken regularly either to treat or prevent malaria. They are taken such that one could even imaging if it is a food supplement. [J Interdiscipl Histopathol 2012; 1(1.000): 26-29

Histological alteration of the pulmonary alveoli, renal cortex and spleen following exposure to open refuse dump site

Background: Wastes are mainly unwanted products from domestic and industrial sources, which increases due to accelerated industrialization, urbanization, and population growth. Open refuse dumping is the predominant form of waste disposal method in Nigeria and presents huge environmental and health challenges. Hence, this study investigated the effects of long‑term exposure of rats to refuse dump sites on histological and serum analysis in three organs; kidney, lungs, and spleen.Materials and Methods: Twelve Wistar rats of both sexes were divided into two groups made up of 6 rats in each group. Group A was the controls and group B was the experimental. The experimental rats were exposed to refuse dump fume by keeping them in a research hut built in a refuse dump site for 8 months while the control rats were keep in the Department of Human Anatomy, Niger Delta University, Wilberforce Island, Bayelsa State. Results: There was loss of the elastic tissue support for bronchioles, alveolar wall and coalescence of adjacent alveoli as compared with the control. Serum urea concentrations were significantly increased (P < 0.05) in exposed rats (9.08 ± 1.58) compared with control rats (5.00 ± 0.32). Similarly, serum creatinine concentrations were significantly increased (P < 0.05) in exposed rats (106.20 ± 14.94) compared to Control rats (53.67 ± 5.68). All measured serum electrolytes were significantly altered (P < 0.05). Sodium ions (Na+) (90.17 ± 7.68) and bicarbonate ions (HCO3−) (2.33 ± 0.33) were significantly reduced (P < 0.05) while potassium ions (K+.) (61.83 ± 6.70) and chloride ions (Cl−) (117.2 ± 3.08) were significantly increased (P < 0.05).Conclusion: Our results revealed histological distortion in experimental animals due to exposure to refuse dump site.Keywords: Alveolar, kidney, necrosis, refuse dump sites, spleen, wast

Histopathology and Anticolon Cancer Effects of Turmeric Ethanolic Extracts in Wistar Rats

Colon cancer is cancer that begins in the large intestine. It usually begins as small, non cancerous clumps that form inside the colon. It typically affects older adults and can occur at any age. The aim of this study is to investigate the histopathological changes of the colon of rats experimentally induced with cadmium chloride as well as the anticancer effect of the ethanolic extract of Curcuma longa. Thirty six healthy albino rats of both sexes were classified into six groups with each group comprising of five rats as follows ; group I: normal control rats, group 2: Cadmium Chloride induced rats, group 3: Aduracil-5 fluorouracil treated rats, Group 4: dimethyl sulfuroxide treated rats, groups 5 and 6 rats were treated with 875mg/kg and 437.5mg/kg of Curcuma ethanolic extracts respectively after initial induction of cancer with cadmium chloride. Comparative observation of the cadmium induced colon showed histopathological damage as evidenced by empty goblet cells, lacerated and suppressed mucosa, destruction of the surface epithelium, features which were lacking in the control and Curcuma longa treated colon. Curcuma treated colon exhibited marked improvement of the histomorphology whilst cadmium treated colon clearly showed tumor cells, cancer cells or invasive inflammatory cells. Adruracil-5fluorouracil{an established anti colon cancer drugs} treated colon showed mild improvement in the histomorphology of the colon while the dimethyl sulfuroxide treated colon revealed an insignificant impact. The ameliorative effect on rat colon occasioned by administration of Curcuma ethanolic extract suggests that the plant product may have therapeutic activity against colon inflammation in albino rats

Environmental Risk Factors for Childhood Acute Lymphoblastic Leukemia: An Umbrella Review

Leukemia is the most common type of cancer among children and adolescents worldwide. The aim of this umbrella review was (1) to provide a synthesis of the environmental risk factors for the onset of childhood acute lymphoblastic leukemia (ALL) by exposure window, (2) evaluate their strength of evidence and magnitude of risk, and as an example (3) estimate the prevalence in the German population, which determines the relevance at the population level. Relevant systematic reviews and pooled analyses were identified and retrieved through PubMed, Web of Science databases and lists of references. Only two risk factors (low doses of ionizing radiation in early childhood and general pesticide exposure during maternal preconception/pregnancy) were convincingly associated with childhood ALL. Other risk factors including extremely low frequency electromagnetic field (ELF-MF), living in proximity to nuclear facilities, petroleum, benzene, solvent, and domestic paint exposure during early childhood, all showed some level of evidence of association. Maternal consumption of coffee (high consumption/>2 cups/day) and cola (high consumption) during pregnancy, paternal smoking during the pregnancy of the index child, maternal intake of fertility treatment, high birth weight (≥4000 g) and caesarean delivery were also found to have some level of evidence of association. Maternal folic acid and vitamins intake, breastfeeding (≥6 months) and day-care attendance, were inversely associated with childhood ALL with some evidence. The results of this umbrella review should be interpreted with caution; as the evidence stems almost exclusively from case-control studies, where selection and recall bias are potential concerns, and whether the empirically observed association reflect causal relationships remains an open question. Hence, improved exposure assessment methods including accurate and reliable measurement, probing questions and better interview techniques are required to establish causative risk factors of childhood leukemia, which is needed for the ultimate goal of primary prevention

A 35-year standardized prediction estimates for gynecological lesions in oil and gas exploration and production city in the Niger Delta

Background: The impact of constant emission of hydrocarbons and contaminated water level through oil spillage in the oil and gas exploration and production areas of Niger Delta on women's health cannot be underestimated. We developed a 35-year standardized prediction estimates for gynecological lesions using data obtained from an integrated specialist hospital serving the residence of the oil and gas exploration and production City of Port Harcourt and the surrounding areas of Niger Delta, Nigeria. Methods: The study participants comprised of 697 females who received medical care at the Braithwaite Memorial Specialist Hospital (BMSH), Port Harcourt, Rivers State, Nigeria, between 2010 and 2014. Predictive modeling of the diseases was performed using JMP statistical discovery™ software, version 12.0 (SAS Institute, Cary, NC, USA). Results: The distribution of the gynecological lesions (n = 697) differed significantly (P < 0.001) by year of diagnosis, developmental stage, age category, and types of lesion. The mean age of study participants was 39.1 ± 12.8 years, and most of the lesions (61.8%) occurred among females who were 30- to 49-year old. Leiomyoma recorded the highest 5-year standardized prevalence rate of 0.508, and with no intervention, it is estimated that the number of cases diagnosed will rise from 235 in 2015 to 1883 by the year 2050. This was followed by ovarian cyst with a prevalence rate of 0.124 and projected increase from 57 in 2015 to 461 by the year 2050. Similarly, the product of conception is also estimated to increase from 34 to 277 by the year 2050. Conclusion: The over 700% increased prediction of gynecological lesions by 2050 calls for urgent attention by both governmental and private agencies to fund awareness campaigns and screenings for women, especially for those residing in the oil- and gas-producing areas of Niger Delta

Risk factors for childhood brain tumours: A systematic review and meta-analysis of observational studies from 1976 to 2022

International audienceBackground: Childhood brain tumours (CBTs) are the leading cause of cancer death in children under the age of 20 years globally. Though the aetiology of CBT remains poorly understood, it is thought to be multifactorial. We aimed to synthesize potential risk factors for CBT to inform primary prevention.Methods: We conducted a systematic review and meta-analysis of epidemiological studies indexed in the PubMed, Web of Science, and Embase databases from the start of those resources through 27 July 2023. We included data from case-control or cohort studies that reported effect estimates for each risk factor around the time of conception, during pregnancy and/or during post-natal period. Random effects meta-analysis was used to estimate summary effect sizes (ES) and 95% confidence intervals (CIs). We also quantified heterogeneity (I2) across studies.Findings: A total of 4040 studies were identified, of which 181 studies (85 case-control and 96 cohort studies) met our criteria for inclusion. Of all eligible studies, 50% (n = 91) were conducted in Europe, 32% (n = 57) in North America, 9% (n = 16) in Australia, 8% (n = 15) in Asia, 1% (n = 2) in South America, and none in Africa. We found associations for some modifiable risk factors including childhood domestic exposures to insecticides (ES 1.44, 95% CI 1.20-1.73) and herbicides (ES 2.38, 95% CI 1.31-4.33). Maternal domestic exposure to insecticides (ES 1.45, 95% CI 1.09-1.94), maternal consumption of cured meat (ES 1.51, 95% CI 1.05-2.17) and coffee ≥ 2 cups/day (ES 1.45, 95% 95% CI 1.07-1.95) during pregnancy, and maternal exposure to benzene (ES 2.22; 95% CI 1.01-4.88) before conception were associated with CBTs in case-control studies. Also, paternal occupational exposure to pesticides (ES 1.48, 95% CI 1.23-1.77) and benzene (ES 1.74, 95% CI 1.10-2.76) before conception and during pregnancy were associated in case-control studies and in combined analysis. On the other hand, assisted reproductive technology (ART) (ES 1.32, 95% CI 1.05-1.67), caesarean section (CS) (ES 1.12, 95% CI 1.01-1.25), paternal occupational exposure to paint before conception (ES 1.56, 95% CI 1.02-2.40) and maternal smoking > 10 cigarettes per day during pregnancy (ES 1.18, 95% CI 1.00-1.40) were associated with CBT in cohort studies. Maternal intake of vitamins and folic acid during pregnancy was inversely associated in cohort studies. Hormonal/infertility treatment, breastfeeding, child day-care attendance, maternal exposure to electric heated waterbed, tea and alcohol consumption during pregnancy were among those not associated with CBT in both case-control and cohort studies.Conclusion: Our results should be interpreted with caution, especially as most associations between risk factors and CBT were discordant between cohort and case-control studies. At present, it is premature for any CBT to define specific primary prevention guidelines