Arsenic Exposure and Melanoma Among US Adults Aged 20 or Older, 2003-2016

Association between arsenic exposure and melanoma: a meta-analysis

BACKGROUND

Melanoma is a highly malignant tumor. Moreover, its prevalence is increasing at a rapid rate year after year. Currently, UV light is the leading cause of melanoma, although numerous other risk factors exist, including arsenic. The link between arsenic and the likelihood of developing melanoma has long been debated. As a result, we conducted a meta-analysis of the available data to investigate the association between arsenic exposure and melanoma.

METHODS

We identified seven non-randomized controlled studies with 41,949 participants by searching the Chinese CNKI, Embase, PubMed, and Cochrane Library databases. We then used random-effects or fixed-effects models to evaluate the pooled odds ratios (OR) and their 95% confidence intervals (CI). Subgroup analyses were also carried out with different included regions.

RESULTS

Participants in the study who were exposed to arsenic had a somewhat higher chance of developing melanoma than those who were not (OR = 1.47, 95% CI 1.01-2.13). A subgroup analysis was also carried out for the US region, and the findings were not statistically significant (OR = 1.40, 95% CI 0.94-2.07).

CONCLUSION

This meta-analysis shows that arsenic exposure relates to an increased risk of melanoma.

Prenatal arsenic exposure alters keratinocyte stem cell fate through persistent activation of IGF2R-MAPK cascade leading to aggravated skin carcinogenesis in mice offspring

Chronic exposure to arsenic (As) promotes skin carcinogenesis in humans and potentially disturbs resident stem cell dynamics, particularly during maternal and early life exposure. In the present study, we demonstrate how only prenatal arsenic exposure disturbs keratinocyte stem cell (KSC) conditioning using a BALB/c mice model. Prenatal As exposure alters the normal stemness (CD34, KRT5), differentiation (Involucrin), and proliferation (PCNA) program in skin of offspring with progression of age as observed at 2, 10, and 18 weeks. Primary KSCs isolated from exposed animal at Day-2 showed increased survival (Bax:Bcl-xL, TUNEL assay), proliferation (BrdU), and differentiation (KRT5, Involucrin) potential through the activation of pro-carcinogenic IGF2R-MAPK cascade (IGF2R-G(α)q-MEK1-ERK1/2). This was associated with reduced enrichment of histone H3K27me3 and its methylase, EZH2 along with increased binding of demethylase, KDM6A at Igf2r promoter. Altered KSCs conditioning through disturbed Igf2r imprint contributed to impaired proliferation and differentiation and an aggravated tumor response in offspring.

Update of the risk assessment of inorganic arsenic in food

The European Commission asked EFSA to update its 2009 risk assessment on arsenic in food carrying out a hazard assessment of inorganic arsenic (iAs) and using the revised exposure assessment issued by EFSA in 2021. Epidemiological studies show that the chronic intake of iAs via diet and/or drinking water is associated with increased risk of several adverse outcomes including cancers of the skin, bladder and lung. The CONTAM Panel used the benchmark dose lower confidence limit based on a benchmark response (BMR) of 5% (relative increase of the background incidence after adjustment for confounders, BMDL05) of 0.06 μg iAs/kg bw per day obtained from a study on skin cancer as a Reference Point (RP). Inorganic As is a genotoxic carcinogen with additional epigenetic effects and the CONTAM Panel applied a margin of exposure (MOE) approach for the risk characterisation. In adults, the MOEs are low (range between 2 and 0.4 for mean consumers and between 0.9 and 0.2 at the 95th percentile exposure, respectively) and as such raise a health concern despite the uncertainties.

Bromoform exposure is associated with non-melanoma skin cancer: evidence from NHANES 2011-2020

Background

Non-melanoma skin cancer (NMSC) is a prevalent skin malignancy. It has been indicated in many studies that trihalomethanes (THMs) exposure has a strong association with tumors but has not been associated with NMSC. Our investigation aims to explore the association between THMs exposure and NMSC.

Methods

Cross-sectional data from the 2011 to 2020 National Health and Nutrition Examination Survey (NHANES) was collected. Poisson regression and subgroup analyses were performed to evaluate the association between individual THMs components and NMSC. Fitted smoothing curves and generalized additive models were also used.

Results

This study involved 5,715 individuals, 98 (1.7%) of whom self-reported NMSC. After adjusting for covariates, Poisson regression showed that higher blood TBM levels were associated with an increased likelihood of NMSC (OR = 1.03; 95% CI: 1.01-1.05, p = 0.002). However, the correlation between the blood levels of TCM, DBCM, and BDCM and the likelihood of NMSC was not statistically significant (all p > 0.05). Subgroup analysis and interaction tests showed no significant differences between blood TBM concentration and the likelihood of NMSC, indicating that age, gender, and race were significantly independent of this positive association (all p < 0.05).

Conclusions

Our results implied that among adults older than 65 years old in the U.S., elevated blood TBM concentrations were positively associated with NMSC. More prospective investigations are required to validate this relationship with the early prevention of NMSC.

Exposure to arsenic, polycyclic aromatic hydrocarbons, metals, and association with skin cancers in the US adults

Worldwide, skin cancer affects millions of people yearly and is broadly classified into melanoma and nonmelanoma types of skin cancer. The toxicity of metals to human health is a public and clinical health problem due to their widespread use in tools, machinery, and appliances as well as their widespread distribution in the air, water, and soil. Arsenic is a carcinogenic metalloid and available in the Earth's crust. Polycyclic aromatic hydrocarbons (PAHs) are toxic to humans, and incomplete combustion of fossil fuels is the main source of PAHs. Human populations exposed to metals from various sources can lead to various diseases including cancer. Limited studies are conducted to simultaneously assess the correlation of multiple arsenic, PAHs, metals with the occurrence of skin cancer. This study aimed to analyze the association between six PAHs compounds, seven types of arsenic, and fourteen metals from urine specimen with skin cancer in US adults. We performed a cross-sectional analysis using data from a total of 14,716 adults from the National Health Examination and Nutrition Survey (NHANES) database for three cycles ranging from 2011-2012 to 2015-2016. Specialized weighted complex survey logit regressions were conducted. Linear logit regression models using only main effects were performed first to identify the correlation between the selected demographic and lifestyle variables and melanoma, nonmelanoma, and unknown types of skin cancer. A second set of linear, main-effects logit regression models were constructed to examine the correlation between melanoma, nonmelanoma, and other types of skin cancers and seven types of arsenic (arsenous acid, arsenic acid, arsenobetaine, arsenocholine, dimethylarsinic acid, monomethylacrsonic acid, and total arsenic), six PAHs (1-hydroxynaphthalene, 2-hydroxynaphthalene, 3-hydroxyfluorene, 2-hydroxyfluorene, 1-hydroxyphenathrene, and 1-hydroxypyrene), and fourteen metals (barium, cadmium, cobalt, cesium, molybdenum, manganese, lead, antimony, tin, strontium, thallium, tungsten, uranium, and mercury) when adjusted for the selected covariates. The statistical analysis was conducted using R software, version 4.0.4. A marginal positive significant correlation between total arsenic and nonmelanoma was observed. This study identified a significant positive association between barium, cadmium, cesium, mercury, tin, and melanoma development. Cesium showed a significant positive statistical association for nonmelanoma, and thallium showed a borderline significant statistical association for nonmelanoma. A statistically significant positive association was found between cadmium and an unknown type of skin cancer. The findings of this study indicated a statistically significant positive association between skin cancer and barium, cadmium, cesium, tin, mercury, and thallium. Further studies are recommended in humans to refute or confirm these findings.

Occupational exposure to arsenic, mercury and UV radiation and risk of melanoma: a case-control study from Italy

BACKGROUND

Melanoma is mainly caused by sunlight radiation, but other environmental risk factors are not well known. We investigated the association between cutaneous melanoma and occupational exposure to arsenic, mercury and UV radiation.

METHODS

A hospital-based case-control study was conducted in the inpatient wards of IDI-San Carlo Rome, Italy, including 304 incident cases of cutaneous melanoma and 305 frequency-matched controls. Detailed sociodemographic, clinical and host-related factors were collected, and all participants were physically examined using dermoscopy and following standard protocol for recording pigmented lesions. Four experts assessed exposure to arsenic, mercury and UV radiation based on occupational history. A multidimensional variable was created for each risk factor, by combining intensity and probability of exposure. Multivariable logistic regression models were run to calculate odds ratios (OR) and 95% confidence intervals (CI) of the association between exposure to these agents and melanoma.

RESULTS

A total of 5.4% of the cases vs 2.4% of the controls were exposed to arsenic (OR = 3.12; 95% CI = 1.10-8.86 for high probability and high exposure to arsenic) after controlling for sex, age, smoking status, number of nevi, phototype and history of sunburns in childhood/adolescence. Occupational exposure to mercury and UV radiation was not associated with the risk of melanoma.

CONCLUSIONS

Subjects exposed to arsenic at the workplace may be at increased risk of developing cutaneous melanoma in comparison to subjects not exposed to this agent. Further studies should be designed to investigate occupational exposure to arsenic and mercury and melanoma and confirm the findings are warranted.

Ambient UVR and Environmental Arsenic Exposure in Relation to Cutaneous Melanoma in Iowa

Intermittent sun exposure is the major environmental risk factor for cutaneous melanoma (CM). Cumulative sun exposure and other environmental agents, such as environmental arsenic exposure, have not shown consistent associations. Ambient ultraviolet radiation (UVR) was used to measure individual total sun exposure as this is thought to be less prone to misclassification and recall bias. Data were analyzed from 1096 CM cases and 1033 controls in the Iowa Study of Skin Cancer and Its Causes, a population-based, case-control study. Self-reported residential histories were linked to satellite-derived ambient UVR, spatially derived environmental soil arsenic concentration, and drinking water arsenic concentrations. In men and women, ambient UVR during childhood and adolescence was not associated with CM but was positively associated during adulthood. Lifetime ambient UVR was positively associated with CM in men (OR for highest vs. lowest quartile: 6.09, 95% confidence interval (CI) 2.21–16.8), but this association was not as strong among women (OR for highest vs. lowest quartile: 2.15, 95% CI 0.84–5.54). No association was detected for environmental soil or drinking water arsenic concentrations and CM. Our findings suggest that lifetime and adulthood sun exposures may be important risk factors for CM.