Lifestyle and Chemicals: Exploring Behavioral Habits Related to Endocrine Disruptor Exposure Among the General Population of Saudi Arabia.

BACKGROUND: Endocrine-disrupting chemicals (EDCs) interfere with hormonal systems, potentially causing metabolic, reproductive, and neurological issues, as well as hormone-related cancers. Found in everyday products, EDCs accumulate in body tissues over time, with adverse effects depending on the dose and duration of exposure. This study aims to explore behaviors related to EDC exposure among Saudi citizens to assess the need for further risk reduction interventions. METHODOLOGY: This cross-sectional study employed a validated, self-administered online questionnaire to assess daily life behaviors associated with EDC exposure. A total of 563 participants were recruited using convenient sampling through online platforms. RESULTS: The study revealed that a significant majority of participants were aged 18-25 years (48.67%, n=274). On average, participants scored 32.78 out of a maximum of 60 for potential EDC exposure, with scores ranging from 13 to 54 points. The majority (85.26%, n=480) fell into the moderate potential exposure category, while a small minority (4.26%, n=24) exhibited high potential risk based on their reported daily habits, predominantly among male participants (95.83%, n=23). A significant majority (72.65%, n=409) indicated a likelihood of adopting lifestyle changes to reduce exposure to harmful substances. CONCLUSION: This study reveals diverse behavioral patterns linked to endocrine disruptor exposure among the general population in Saudi Arabia. Interestingly, the participants showed a positive attitude and willingness to change their risky behaviors. These findings underscore the necessity for educational programs and public health campaigns aimed at addressing gaps in knowledge. Encouraging the public to adopt behaviors that reduce exposure is essential to minimizing the potential long-term effects of EDCs.

Environmental Signals.

Environmental factors have long been known to play a role in the pathogenesis of congenital heart disease (CHD), but this has not been a major focus of research in the modern era. Studies of human exposures and animal models demonstrate that demographics (age, race, socioeconomic status), diseases (e.g., diabetes, hypertension, obesity, stress, infection, high altitude), recreational and therapeutic drug use, and chemical exposures are associated with an increased risk for CHD. Unfortunately, although studies suggest that exposures to these factors may cause CHD, in most cases, the data are not strong, are inconclusive, or are contradictory. Although most studies concentrate on the effects of maternal exposure, paternal exposure to some agents can also modify this risk. From a mechanistic standpoint, recent delineation of signaling and genetic controls of cardiac development has revealed molecular pathways that may explain the effects of environmental signals on cardiac morphogenesis and may provide further tools to study the effects of environmental stimuli on cardiac development. For example, environmental factors likely regulate cellular signaling pathways, transcriptional and epigenetic regulation, proliferation, and physiologic processes that can control the development of the heart and other organs. However, understanding of the epidemiology and risk of these exposures and the mechanistic basis for any effects on cardiac development remains incomplete. Further studies defining the relationship between environmental exposures and human CHD and the mechanisms involved should reveal strategies to prevent, diagnose, and treat CHD induced by environmental signals.

Machine learning-derived dose-response relationships considering interactions in mixtures: Applications to the oxidative potential of particulate matter.

Conventional environmental health research is primarily focused on isolated chemical exposures, neglecting the complex interactions between multiple pollutants that may synergistically or antagonistically influence toxicity, thereby posing unexpected health risks. In this study, we address this knowledge gap by introducing an explainable machine learning (ML) approach with Feature Localized Intercept Transformed-Shapley Additive Explanations (FLIT-SHAP) designed to extract the dose-response relationships of specific pollutants in mixtures. In contrast to traditional SHAP, FLIT-SHAP can localize the global intercept to elucidate mixture effects, which is crucial for understanding the oxidative potential (OP) of ambient particulate matter (PM). Assessing multi-pollutant OP using FLIT-SHAP revealed both synergistic (55-63 %) and antagonistic (25-42 %) effects in laboratory-controlled OP data, but an antagonistic (33-66 %; lower OP) effect in ambient PM. Notably, the FLIT-SHAP approach demonstrated higher prediction accuracy (R2 = 0.99) compared to the additive model (R2 = 0.89) when evaluated against real-world PM samples. Quinones, such as phenanthrenequinone, play a more significant role in PM2.5 than previously recognized. Through this study, we highlighted the potential of FLIT-SHAP to enhance toxicity predictions and aid decision-making in the field of environmental health.

Permeation of a firearm cleaning solvent through disposable nitrile gloves.

The objective was to study the interaction of the components of a complex liquid mixture on the permeation parameters of its constituents. A firearm cleaning solvent, Hoppes No. 9 Gun Bore Cleaner, was selected to challenge two varieties of disposable nitrile gloves, the thinnest (Kimberly-Clark Lavender) and thickest (Kimberly-Clark Blue), using the closed-loop ASTM F739 cell without recirculation and n-decane collection followed by quantitation of the permeated compounds using capillary gas chromatography-mass spectrometry. The thicker Blue glove resisted the permeation of Hoppe's relative to the thinner Lavender glove as shown by 3.2 times more mass permeated by the Lavender glove at 60 min despite the same standardized breakthrough times (7.5 ± 2.5 min). The kerosene fraction permeated faster at a much higher rate than expected. The Kimberly-Clark disposable nitrile glove chemical resistance guide lists a breakthrough time for kerosene of 82 min for Sterling disposable nitrile glove material. However, for Hoppe's the kerosene components appeared at the standardized breakthrough time. Mixture components that were reported by the glove manufacturer to quickly permeate the disposable nitrile material, such as ethanol, did not permeate at a rate slower than expected, indicative of a possible carrier function. A semiquantitative risk assessment confirmed the unacceptability of both gloves. Persons using personal protective equipment, such as gloves, may not be afforded the expected resistance to chemical permeation when chemicals are in a suitable mixture, hence enhancing the risk of exposure. More research is needed to produce better glove testing measures to ensure the safety of workers.

Estimation of intake and quantification of hemoglobin adducts of acrylamide in adolescents in Sweden.

Blood samples (n = 600) from participants in the Swedish dietary survey Riksmaten Adolescents 2016-17 were analyzed with respect to hemoglobin (Hb) adducts from acrylamide (AA) and its metabolite glycidamide (GA) as biomarkers of internal dose/exposure. The results are presented from statistical analyses of food consumption data (2-day dietary recall and questionnaires) and measured Hb adduct levels. The estimated exposure as well as consumption data were examined in relation to non-dietary factors such as sex, age (group medians of 12, 15, and 18 years), place of residence (urban/rural), smoking status, and parental education level. The median AA adduct level was estimated to be 34 pmol/g Hb (range 14-225). No significant difference was found for place of residence, parental education, sex, or age. A significant difference was found between the median adduct levels of daily smokers (n = 8) and never smokers (n = 323) in the older age groups, but not between occasional smokers (n = 47) and never smokers. The median differences between daily smokers and never smokers were 76, 40, and 128 pmol/g Hb for AA, GA, and AA + GA, respectively. The median AA intake for the whole group of adolescents, as estimated from dietary recall data combined with reported concentrations in food, was 0.40 µg/kg bw/day. The corresponding median intake estimated from measured Hb adduct levels of AA was 0.20 µg/kg bw/day. A significant, although low, positive Spearman correlation was found between the two intake estimates (p-value = 8 × 10-3; ρ = 0.11). From the estimated intake of AA from food frequency questionnaires, significance was found for the 15-year-old children with higher AA adduct levels observed at higher consumption frequencies of fried potatoes/French fries. AA is considered a genotoxic carcinogen. For the estimated intake of AA for any age group and method (dietary recall or AA adduct), both a calculated margin of exposure as well as lifetime quantitative cancer risk estimates indicate health concern. A future study on food consumption designed with respect to AA exposure would provide a better understanding of the correlation between consumption and exposure and should give a more reliable estimate of the contribution of dietary AA to the overall cancer risk.

Recent use of consumer and personal care products and exposures to select endocrine disrupting chemicals among urban children with asthma.

BACKGROUND: Emerging studies suggest that endocrine disrupting chemicals (EDCs) in personal care and other consumer products are linked with various adverse health effects, including respiratory and reproductive effects. Despite Black persons using more personal care products than other demographic groups and having a high asthma burden, little is known regarding their consumer product use patterns and associated EDC exposures. OBJECTIVE: To examine the association between recent exposure to select EDCs with specific consumer products and behaviors in a cohort of 110 predominantly Black children with asthma, ages 8-17 years, living in Baltimore City, Maryland. METHODS: We quantified concentrations of bisphenol A (BPA), bisphenol S (BPS), bisphenol F, two dichlorophenols, four parabens, triclosan, benzophenone-3, and triclocarban in spot urine samples. Questionnaires were used to capture recent (last 24-h) consumer product use and behaviors. Associations between EDCs and consumer product uses/behaviors were assessed using multivariable linear regression, adjusting for age, gender, race/ethnicity, and caregiver income level. Effect estimates were expressed as geometric mean ratios of biomarker concentrations of product-users vs non-users. RESULTS: Increased concentrations to select EDCs were associated with recent use of air freshener (ratios; BPA: 1.9, 95%CI 1.4-2; BPS 1.7, 95%CI 1-2.97; propyl paraben: 3.0, 95%CI 1.6-5.6), scented candles (methyl paraben: 2.6, 95%CI 1.1-6.1), and scented carpet powder (2,5-dichlorophenol: 2.8, 95%CI 1.2-6.3). Additionally, consuming canned food was associated with some increased biomarker concentrations (ratios: BPA: 1.7, 95%CI 1.2-2.4; BPS: 2.1, 95% CI: 1.2-3.6). SIGNIFICANCE: These findings add to the body of evidence suggesting that recent use of select consumer products in Black children contributes to exposure of chemicals of concern and could potentially inform exposure mitigation interventions. Findings have broad potential health implications for pediatric populations and Black children who may face exposure and health disparities. IMPACT: Little is known about how children's personal care product use and consumer behaviors affect their exposures to endocrine disrupting chemicals (EDCs). This is particularly true for Black children who often experience a disparate exposure burden to many EDCs. This is a significant knowledge gap among children that are uniquely vulnerable to EDCs as they undergo critical windows of growth and development. Our findings show associations between consumer products and EDC exposures in predominantly Black children in low-income settings. Identifying EDC exposure determinants has broad health implications as many of these chemicals have been associated with adverse health risks.

Determination of the urinary concentrations of six bisphenols in public servants by online solid-phase extraction-liquid chromatography tandem mass spectrometry.

Bisphenols are widely used as monomers and additives in plastic production. Thus, bisphenol A (BPA) and its most prominent substitutes have been detected in many environmental and human samples. This study proposes an online solid-phase extraction analytical methodology coupled to liquid chromatography with tandem mass spectrometry for the determination of six bisphenols (BPA and bisphenols F (BPF), S (BPS), AF (BPAF), B (BPB), and E (BPE)) in urine samples as an efficient and automated methodology. The method was developed and validated for all bisphenols with good recoveries (92-112%) and repeatability (RSD ≤ 10%) despite the variable matrix effects, except BPAF (which would require a dedicated internal standard), achieving method quantification limits in the 0.05-2.2 ng mL-1 range. The methodology was subsequently applied to 435 urine samples from a non-occupational exposure population (civil servants for the regional government) from Santiago de Compostela (Galicia, Spain). Only BPA, BPF, and BPS were positively detected; the last two presented higher detection frequencies than BPA. When the urinary concentrations are extrapolated to human intake and compared to the European Food Safety Agency (EFSA) tolerable daily intake (TDI) of 2 × 10-4 µg kg-1 day-1 (TDI), all BPA positively identified samples would surpass this threshold. Although no TDI exists currently for the other two identified bisphenols, it is evident that human exposure to bisphenols should be limited. Finally, the results stratification by gender revealed higher levels of exposure to BPF in the women group.

Differences in the anatomy and physiology of the human and rat respiratory tracts and impact on toxicological assessments.

Inhalation is a critical route through which substances can exert adverse effects in humans; therefore, it is important to characterize the potential effects that inhaled substances may have on the human respiratory tract by using fit for purpose, reliable, and human relevant testing tools. In regulatory toxicology testing, rats have primarily been used to assess the effects of inhaled substances as they-being mammals-share similarities in structure and function of the respiratory tract with humans. However, questions about inter-species differences impacting the predictability of human effects have surfaced. Disparities in macroscopic anatomy, microscopic anatomy, or physiology, such as breathing mode (e.g., nose-only versus oronasal breathing), airway structure (e.g., complexity of the nasal turbinates), cell types and location within the respiratory tract, and local metabolism may impact inhalation toxicity testing results. This review shows that these key differences describe uncertainty in the use of rat data to predict human effects and supports an opportunity to harness modern toxicology tools and a detailed understanding of the human respiratory tract to develop testing approaches grounded in human biology. Ultimately, as the regulatory purpose is protecting human health, there is a need for testing approaches based on human biology and mechanisms of toxicity.

Maternal exposure to bisphenols, phthalates, perfluoroalkyl acids, and trace elements and their associations with gestational diabetes mellitus in the APrON cohort.

The increasing global prevalence of gestational diabetes mellitus (GDM) has been hypothesized to be associated with maternal exposure to environmental chemicals. Here, among 420 women participating in the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort study, we examined associations between GDM and second trimester blood or urine concentrations of endocrine disrupting chemicals (EDCs): bisphenol-A (BPA), bisphenol-S (BPS), twelve phthalate metabolites, eight perfluoroalkyl acids (PFAAs), and eleven trace elements. Fifteen (3.57%) of the women were diagnosed with GDM, and associations between the environmental chemical exposures and GDM diagnosis were examined using multiple logistic and LASSO regression analyses in single- and multi-chemical exposure models, respectively. In single chemical exposure models, BPA and mercury were associated with increased odds of GDM, while a significant inverse association was observed for zinc. Double-LASSO regression analysis selected mercury (AOR: 1.51, CI: 1.12-2.02), zinc (AOR: 0.017, CI: 0.0005-0.56), and perfluoroundecanoic acid (PFUnA), a PFAAs, (AOR: 0.43, CI: 0.19-0.94) as the best predictors of GDM. The combined data for this Canadian cohort suggest that second trimester blood mercury was a robust predictor of GDM diagnosis, whereas blood zinc and PFUnA were protective factors. Research into mechanisms that underlie the associations between mercury, zinc, PFUnA, and the development of GDM is needed.

A systematic review and meta-analysis of environmental contaminant exposure impacts on weight loss and glucose regulation during calorie-restricted diets in preclinical studies: Persistent organic pollutants may impede glycemic control.

Epidemiological evidence links chemical exposure with type 2 diabetes (T2DM) risk and prevalence. Chemical exposure may therefore also limit success of weight loss or restoration of glycemic control during calorie restricted diets. Few human studies examine this hypothesis. This systematic review and clustered meta-analysis examines preclinical evidence that exposure to anthropogenic environmental contaminants impedes weight loss and resumption of glycemic control during calorie restriction. Of five eligible papers from 212 unique citations, four used C57BL/6 mice and one used Sprague Dawley rats. In four the animals received high fat diets to induce obesity and impaired glycemic control. All examined persistent organic pollutants (POPs). Polychlorinated biphenyl (PCB) 77 exposure did not affect final mass (standardised mean difference (SMD) = -0.35 [-1.09, 0.39]; n = 5 (experiments); n = 3 (papers)), or response to insulin in insulin tolerance tests (SMD = -1.54 [-3.25, 0.16] n = 3 (experiments); n = 2 (papers)), but impaired glucose control in glucose tolerance tests (SMD = -1.30 [-1.96, -0.63]; n = 6 (experiments); n = 3 (papers)). The impaired glycemic control following perfluoro-octane sulphonic acid (PFOS) exposure and enhanced mass loss following dichlorodiphenyltrichloroethane (DDT) exposure have not been replicated. Animal studies thus suggest some chemical groups, especially PCB and PFOS, could impair glucose control management during calorie restriction, similar to conclusions from limited existing clinical studies. We discuss the research that is urgently required to inform weight management services that are now the mainstay prevention initiative for T2DM.

Applying Cell Painting in Non-Tumorigenic Breast Cells to Understand Impacts of Common Chemical Exposures.

There are a substantial number of chemicals to which individuals in the general population are exposed which have putative, but still poorly understood, links to breast cancer. Cell Painting is a high-content imaging-based in vitro assay that allows for rapid and unbiased measurements of the concentration-dependent effects of chemical exposures on cellular morphology. We optimized the Cell Painting assay and measured the effect of exposure to 16 human exposure relevant chemicals, along with 21 small molecules with known mechanisms of action, for 48 hours in non-tumorigenic mammary epithelial cells, the MCF10A cell line. Through unbiased imaging analyses using CellProfiler, we quantified 3042 morphological features across approximately 1.2 million cells. We used benchmark concentration modeling to quantify significance and dose-dependent directionality to identify morphological features conserved across chemicals and find features that differentiate the effects of toxicants from one another. Benchmark concentrations were compared to chemical exposure biomarker concentration measurements from the National Health and Nutrition Examination Survey to assess which chemicals induce morphological alterations at human-relevant concentrations. Morphometric fingerprint analysis revealed similar phenotypes between small molecules and prioritized NHANES-toxicants guiding further investigation. A comparison of feature fingerprints via hypergeometric analysis revealed significant feature overlaps between chemicals when stratified by compartment and stain. One such example was the similarities between a metabolite of the organochlorine pesticide DDT (p,p'-DDE) and an activator of canonical Wnt signaling CHIR99201. As CHIR99201 is a known Wnt pathway activator and its role in ß-catenin translocation is well studied, we studied the translocation of ß-catenin following p'-p' DDE exposure in an orthogonal high-content imaging assay. Consistent with activation of Wnt signaling, low dose p',p'-DDE (25nM) significantly enhances the nuclear translocation of ß-catenin. Overall, these findings highlight the ability of Cell Painting to enhance mode-of-action studies for toxicants which are common exposures in our environment but have previously been incompletely characterized with respect to breast cancer risk.

Changes in plasma concentrations of per- and Polyfluoroalkyl substances after bariatric surgery in adolescents from the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study.

Exposure to per- and poly-fluoroalkyl substances (PFAS) is ubiquitous due to their persistence in the environment and in humans. Extreme weight loss has been shown to influence concentrations of circulating persistent organic pollutants (POPs). Using data from the multi-center perspective Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) cohort, we investigated changes in plasma-PFAS in adolescents after bariatric surgery. Adolescents (Mean age = 17.1 years, SD = 1.5 years) undergoing bariatric surgery were enrolled in the Teen-LABS study. Plasma-PFAS were measured at the time of surgery and then 6-, 12-, and 36 months post-surgery. Linear mixed effect models were used to evaluate longitudinal changes in plasma-PFAS after the time of bariatric surgery. This study included 214 adolescents with severe obesity who had available longitudinal measures of plasma-PFAS and underwent bariatric surgery between 2007 and 2012. Underlying effects related to undergoing bariatric surgery were found to be associated with an initial increase or plateau in concentrations of circulating PFAS up to 6 months after surgery followed by a persistent decline in concentrations of 36 months (p < 0.001 for all plasma-PFAS). Bariatric surgery in adolescents was associated with a decline in circulating PFAS concentrations. Initially following bariatric surgery (0-6 months) concentrations were static followed by decline from 6 to 36 months following surgery. This may have large public health implications as PFAS are known to be associated with numerous metabolic related diseases and the significant reduction in circulating PFAS in individuals who have undergone bariatric surgery may be related to the improvement of such metabolic related diseases following bariatric surgery.

Innovative analytical methodologies for characterizing chemical exposure with a view to next-generation risk assessment.

The chemical burden on the environment and human population is increasing. Consequently, regulatory risk assessment must keep pace to manage, reduce, and prevent adverse impacts on human and environmental health associated with hazardous chemicals. Surveillance of chemicals of known, emerging, or potential future concern, entering the environment-food-human continuum is needed to document the reality of risks posed by chemicals on ecosystem and human health from a one health perspective, feed into early warning systems and support public policies for exposure mitigation provisions and safe and sustainable by design strategies. The use of less-conventional sampling strategies and integration of full-scan, high-resolution mass spectrometry and effect-directed analysis in environmental and human monitoring programmes have the potential to enhance the screening and identification of a wider range of chemicals of known, emerging or potential future concern. Here, we outline the key needs and recommendations identified within the European Partnership for Assessment of Risks from Chemicals (PARC) project for leveraging these innovative methodologies to support the development of next-generation chemical risk assessment.

When Does Multiphase Chemistry Influence Indoor Chemical Fate?

Human chemical exposure often occurs indoors, where large variability in contaminant concentrations and indoor chemical dynamics make assessments of these exposures challenging. A major source of uncertainty lies in the rates of chemical transformations which, due to high surface-to-volume ratios and rapid air change rates relative to rates of gas-phase reactions indoors, are largely gas-surface multiphase processes. It remains unclear how important such chemistry is in controlling indoor chemical lifetimes and, therefore, human exposure to both parent compounds and transformation products. We present a multimedia steady-state fugacity-based model to assess the importance of multiphase chemistry relative to cleaning and mass transfer losses, examine how the physicochemical properties of compounds and features of the indoor environment affect these processes, and investigate uncertainties pertaining to indoor multiphase chemistry and chemical lifetimes. We find that multiphase reactions can play an important role in chemical fate indoors for reactive compounds with low volatility, i.e., octanol-air equilibrium partitioning ratios (Koa) above 108, with the impact of this chemistry dependent on chemical identity, oxidant type and concentration, and other parameters. This work highlights the need for further research into indoor chemical dynamics and multiphase chemistry to constrain human exposure to chemicals in the built environment.

The effect of occupational exposure to noise and chemical agents on hearing abilities.

Exposure to loud noise or chemical agents may cause hearing disorders such as tinnitus and recruitment, known as an increase in the perception of loudness in addition to hearing loss. Our study aims to evaluate the hearing abilities of hairdressers exposed to noise and chemical agents in the working environment. The study included one hundred hairdressers and one hundred participants who do not work as hairdressers or are nonworkers. The participants' demographic characteristics, working conditions, and auditory complaints were questioned, and each participant completed the Speech, Spatial, and Qualities of Hearing Scale (SSQ). A statistically significant difference was found between the two groups in speech perception, spatial perception, hearing quality, and general SSQ scores. Hairdressers' SSQ scores were significantly lower in all sub-dimensions and general scale scores (p < 0.001). The auditory complaints of the hairdressers and the low SSQ scores indicate that exposure to noise and chemical agents affects the hairdressers' hearing system.

Occupational exposures and cancer risk in commercial laundry and dry cleaning industries: a scoping review.

BACKGROUND: The laundry and dry cleaning industries are critical for maintaining cleanliness and hygiene in our daily lives. However, they have also been identified as sources of hazardous chemical exposure for workers, leading to potentially severe health implications. Despite mounting evidence that solvents like perchloroethylene and trichloroethylene are carcinogenic, they remain commonly used in the industry. Additionally, while alternative solvents are increasingly being utilized in response to indications of adverse health and environmental effects, there remains a significant gap in our understanding of the potential risks associated with exposure to these new agents. METHODS: This study aims to identify gaps in the literature concerning worker exposure to contemporary toxic chemicals in the laundry and dry cleaning industry and their associated carcinogenic risks. A scoping review of peer-reviewed publications from 2012 to 2022 was conducted to achieve this objective, focusing on studies that detailed chemical exposures, sampling methods, and workers within the laundry and dry cleaning sector. RESULTS: In this scoping review, 12 relevant papers were assessed. A majority (66%) examined perchloroethylene exposure, with one notable finding revealing that biomarkers from dry cleaners had significant micronuclei frequency and DNA damage, even when exposed to PCE at levels below occupational exposure limits. Similarly, another study supported these results, finding an increase in early DNA damage among exposed workers. Separate studies on TCE and benzene presented varied exposure levels and health risks, raising concern due to their IARC Group 1 carcinogen classification. Information on alternative solvents was limited, highlighting gaps in health outcome data, exposure guidelines, and carcinogenic classifications. CONCLUSION: Research on health outcomes, specifically carcinogenicity from solvent exposure in dry cleaning, is limited, with 66% of studies not monitoring health implications, particularly for emerging solvents. Further, findings indicated potential DNA damage from perchloroethylene, even below set occupational limits, emphasizing the need to reevaluate safety limits. As alternative solvents like butylal and high-flashpoint hydrocarbons become more prevalent, investigations into the effects of their exposure are necessary to safeguard workers' health. This scoping review is registered with the Open Science Framework, registration DOI: https://doi.org/10.17605/OSF.IO/Q8FR3 .

Prenatal exposure to metals and autism spectrum disorder: Current status and future directions.

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder with genetic and environmental contributors to etiology. Many metals have the potential to be neurotoxic and their exposures are widespread. The field of metals exposure and ASD research is emerging, and in this review article we assess the current state of the literature, with emphasis on the previous two years. Epidemiology studies are discussed with respect to exposure timing, exposure matrix, and outcome assessment. Toxicology studies are described for exposure dosing and timing, as well as behavioral and molecular outcomes. Further epidemiological and toxicological investigations can identify the timing and importance of metals as ASD risk factors and uncover biological mechanisms for risk mitigation and therapeutic strategies.

Contaminación, disruptores endocrinos y cáncer / Contamination, endocrine disruptors and cancer

Desde mediados del siglo XX numerosas especies, muy diferentes entre sí y ubicadas en todas las áreas y rincones del planeta, comenzaron a presentar diversas alteraciones, muchas de las cuales sugerían estar relacionadas con trastornos del sistema endocrino. Las investigaciones demostraron que tales alteraciones eran producidas por la exposición a diferentes sustancias químicas contaminantes, las cuales podían alterar la salud y producir graves enfermedades. Dentro de ellas destacó un grupo heterogéneo de compuestos con estructuras químicas muy diferentes, capaces de actuar a dosis muy bajas, mostrar distintos mecanismos de acción y ser capaces de alterar el equilibrio hormonal, por lo que se les denominó “disruptores endocrinos químicos”. Estas sustancias, al ser liberadas al medioambiente o formar parte de objetos, alimentos o medicinas, constituyen un gran riesgo para los seres humanos y toda la vida del planeta, produciendo no solo disfunciones endocrinas sino también diferentes tipos de cáncer, destacando los más frecuentes. A pesar de la trascendencia y significado del impacto de estos compuestos, ellos no son suficientemente conocidos ni entendidos, por lo que el objetivo de esta revisión es mostrar su origen e impacto en la salud humana, resaltando su papel como inductores de cáncer, lo cual ha motivado múltiples investigaciones clínicas y biológicas.

Since the mid-twentieth century, many species, very different from each other and located in all areas and corners of the planet, began presenting various alterations, many of which suggested to be related to endocrine disorders. Research has shown that such alterations were caused by exposure to various chemical contaminants that could affect the health and cause serious illnesses. Among them stands a diverse and large group of compounds, with very different chemical structures, capable of altering the hormonal balance, act at very low doses and with different mechanisms of action, that are called “endocrine disrupting chemicals”. When released into the environment or as part of objects, food or medicines, constitute a major risk to animals and humans, which produces not only endocrine dysfunctions but also different cancers, which include the most common types. Despite the importance and significance of the impact of these compounds, they are not sufficiently known or understood, so the aim of this review is to show their origin and impact in the field of human health, highlighting their role as inducers of cancer, which has led to multiple clinical and biological investigations.