Mortality from stomach cancer in Ontario miners

A comprehensive review on human health effects of chromium: insights on induced toxicity

The growing use of heavy metals in most industrial activities has led to it being considered as the most important environmental pollutant that may cause harm and toxicity to animals and humans. Chromium has been found in the environment in different oxidation states such as Cr⁰, Cr(III), and Cr(VI) and is released from a variety of anthropogenic and natural activities. At among, trivalent and hexavalent chromium are the most stable forms. Considerably, Cr(VI) is frequently more toxic than Cr(III) because of its particular solubility and high mobility. Chronic exposure and bioaccumulation of chromium, as a heavy metal, can cause toxicity and numerous pathophysiological defects, including allergic reactions, anemia, burns, and sores especially in the stomach and small intestine, damage to sperm along with the male reproductive system, and affect various biological systems. Chromium pollution can have severe consequences for water and the soil environment. This article reviews the toxicological effects of Cr(VI) and Cr(III) and their mechanisms of toxicity and carcinogenicity.

Risk assessment of chromium and cadmium emissions from the consumption of premium motor spirit (PMS) and automotive gas oil (AGO) in Nigeria

This paper assessed the chromium and cadmium emissions from consumption of premium motor spirit (PMS) and automotive gas oil (AGO) across the states, regions and the nation, Nigeria as a whole. This was with a view to determining the levels of per capita and land exposures to the emissions and the associated risks to humans, plants and animals. Annual fuel consumption and toxic transition metals contents were combined to estimate the annual emission rates of chromium and cadmium emissions from combustion of the PMS and AGO for a period of ten years (2009–2018). Per capita and land distributions of emissions were then calculated by using population and land areas, respectively. The results showed that total emission rates from both PMS and AGO were lowest in 2012, with 1,102 million mg/yr of chromium and 3,253 million mg/yr of cadmium, and highest in 2018, with 14,454 million mg/yr of chromium and 39,580 million mg/yr of cadmium. Emission rates per capita were also lowest in 2012, with 7 mg/yr.person of chromium and 20 mg/yr.person of cadmium, and highest in 2018 with 74 mg/yr.person of chromium and 201 mg/yr.person of cadmium. Land distribution was lowest in 2012, with 1.19 mg/yr.km² of chromium and 3.52 mg/yr.km² of cadmium, and highest in 2018, with 15.63 mg/yr.km² of chromium and 42.81 mg/yr.km² of cadmium. Comparing to regulatory limits, the risks of humans, animals and plants be poisoned are very high. It is recommended that stiff regulations concerning the heavy metal contents of fuels imported and distributed in Nigeria should be created and implemented to mitigate the risks of poisoning to humans, animals and crops.

Introducing biomarker panel in esophageal, gastric, and colon cancers; a proteomic approach

Cancer research is an attractive field in molecular biology and medicine. By applying large-scale tools such as advanced genomics and proteomics, cancer diagnosis and treatment have been improved greatly. Cancers of esophagus, gastric, and colon accounted for major health problem globally. Biomarker panel could bring out the accuracy for cancer evaluation tests as it can suggest a group of candidate molecules specified to particular malignancy in a way that distinguishing malignant tumors from benign, differentiating from other diseases, and identifying each stages with high specificity and sensitivity. In this review, a systematic search of unique protein markers reported by several proteomic literatures are classified in their specific cancer type group as novel panels for feasible accurate malignancy diagnosis and treatment. About thousands of introduced proteins were studied; however, a small number of them belonged to a specific kind of malignancy. In conclusion, despite the fact that combinatorial biomarkers appear to be hopeful, more evaluation of them is crucial to achieve the suitable biomarker panel for clinical application. This effort needs more investigations and researches for finding a specific and sensitive panel.

Radon and risk of extrapulmonary cancers: results of the German uranium miners' cohort study, 1960-2003

Data from the German miners' cohort study were analysed to investigate whether radon in ambient air causes cancers other than lung cancer. The cohort includes 58,987 men who were employed for at least 6 months from 1946 to 1989 at the former Wismut uranium mining company in Eastern Germany. A total of 20,684 deaths were observed in the follow-up period from 1960 to 2003. The death rates for 24 individual cancer sites were compared with the age and calendar year-specific national death rates. Internal Poisson regression was used to estimate the excess relative risk (ERR) per unit of cumulative exposure to radon in working level months (WLM). The number of deaths observed (O) for extrapulmonary cancers combined was close to that expected (E) from national rates (n=3340, O/E=1.02; 95% confidence interval (CI): 0.98-1.05). Statistically significant increases in mortality were recorded for cancers of the stomach (O/E=1.15; 95% CI: 1.06-1.25) and liver (O/E=1.26; 95% CI: 1.07-1.48), whereas significant decreases were found for cancers of the tongue, mouth, salivary gland and pharynx combined (O/E=0.80; 95% CI: 0.65-0.97) and those of the bladder (O/E=0.82; 95% CI: 0.70-0.95). A statistically significant relationship with cumulative radon exposure was observed for all extrapulmonary cancers (ERR/WLM=0.014%; 95% CI: 0.006-0.023%). Most sites showed positive exposure-response relationships, but these were insignificant or became insignificant after adjustment for potential confounders such as arsenic or dust exposure. The present data provide some evidence of increased risk of extrapulmonary cancers associated with radon, but chance and confounding cannot be ruled out.

Lung cancer and dust exposure: results of a prospective cohort study following 3260 workers for 50 years

AIMS

To study the lasting health impact of occupational dust exposure on life expectancy and specific causes of death.

METHODS

Male Viennese workers, selected at age > or =40 (mean 54) years during preventive check-ups between 1950 and 1960, were followed prospectively until death. Half of them (1630) were exposed at work to (non-fibrous) particulates, while the non-exposed workers were matched for year, age, and smoking status at the start of observation.

RESULTS

Average life expectancy of those exposed was 1.6 years less than that of those non-exposed. Only a small part of this decrease in life expectancy (hazards ratios in brackets) was related to acknowledged occupational diseases such as silicosis and silicotuberculosis (67.12). Chronic obstructive lung disease (1.82) and cancer of the lung (1.42) and stomach (1.77) were found more frequently among those exposed.

CONCLUSIONS

Results support the hypothesis that high exposure to insoluble particulates such as silica in the metal, glass, ceramics, and stone industries promotes bronchial cancer and chronic obstructive pulmonary disease. The finding of an increased incidence of stomach cancer might be related to particles swallowed after clearance from the airways.

Health risks of gold miners: a synoptic review

Health problems of gold miners who worked underground include decreased life expectancy; increased frequency of cancer of the trachea, bronchus, lung, stomach, and liver; increased frequency of pulmonary tuberculosis (PTB), silicosis, and pleural diseases; increased frequency of insect-borne diseases, such as malaria and dengue fever; noise-induced hearing loss; increased prevalence of certain bacterial and viral diseases; and diseases of the blood, skin, and musculoskeletal system. These problems are briefly documented in gold miners from Australia, North America, South America, and Africa. In general, HIV infection or excessive alcohol and tobacco consumption tended to exacerbate existing health problems. Miners who used elemental mercury to amalgamate and extract gold were heavily contaminated with mercury. Among individuals exposed occupationally, concentrations of mercury in their air, fish diet, hair, urine, blood, and other tissues significantly exceeded all criteria proposed by various national and international regulatory agencies for protection of human health. However, large-scale epidemiological evidence of severe mercury-associated health problems in this cohort was not demonstrable.

Occupation and gastric cancer

Gastric cancer is a cause of significant morbidity and mortality. There are several risk factors, with occupation emerging as one of these. There is considerable evidence that occupations in coal and tin mining, metal processing, particularly steel and iron, and rubber manufacturing industries lead to an increased risk of gastric cancer. Other "dusty" occupations-for example, wood processing, or work in high temperature environments have also been implicated but the evidence is not strong. The mechanism of pathogenesis of gastric cancer is unclear and the identification of causative agents can be difficult. Dust is thought to be a contributor to the pathological process, but well known carcinogens such as N-nitroso compounds have been detected in some environments. Further research on responsible agents is necessary and screening for detection of precursor gastric cancer lesions at the workplace merits consideration.

Occupational silica exposure and risk of various diseases: an analysis using death certificates from 27 states of the United States

BACKGROUND

Although crystalline silica exposure is associated with silicosis, lung cancer, pulmonary tuberculosis, and chronic obstructive pulmonary disease (COPD), there is less support for an association with autoimmune disease, and renal disease.

METHODS

Using data from the US National Occupational Mortality Surveillance (NOMS) system, a matched case-control design was employed to examine each of several diseases (including silicosis, lung cancer, stomach cancer, oesophageal cancer, COPD, pulmonary tuberculosis, sarcoidosis, systemic lupus erythematosus, systemic sclerosis, rheumatoid arthritis, and various types of renal disease). Cases were subjects whose death certificate mentioned the disease of interest. A separate control group for each of the diseases of interest was selected from among subjects whose death certificate did not mention the disease of interest or any of several diseases reported to be associated with crystalline silica exposure. Subjects were assigned into a qualitative crystalline silica exposure category based on the industry/occupation pairing found on their death certificate. We also investigated whether silicotics had a higher risk of disease compared to those without silicosis.

RESULTS

Those postulated to have had detectable crystalline silica exposure had a significantly increased risk for silicosis, COPD, pulmonary tuberculosis, and rheumatoid arthritis. In addition, a significant trend of increasing risk with increasing silica exposure was observed for these same conditions and for lung cancer. Those postulated to have had the greatest crystalline silica exposure had a significantly increased risk for silicosis, lung cancer, COPD, and pulmonary tuberculosis only. Finally, those with silicosis had a significantly increased risk for COPD, pulmonary tuberculosis, and rheumatoid arthritis.

CONCLUSIONS

This study corroborates the association between crystalline silica exposure and silicosis, lung cancer, COPD, and pulmonary tuberculosis. In addition, support is provided for an association between crystalline silica exposure and rheumatoid arthritis.