Endotoxin enhances respiratory effects of phthalates in adults: Results from NHANES 2005-6

Longitudinal measures of phthalate exposure and asthma exacerbation in a rural agricultural cohort of Latino children in Yakima Valley, Washington

Phthalates are a class of widely used synthetic chemicals found in commonly used materials and products. Epidemiological studies suggest phthalate exposure is associated with asthma outcomes, though most studies have not investigated phthalates as triggers of exacerbations in children diagnosed with asthma. This study used data from the Home Air in Agriculture Pediatric Intervention Trial (HAPI) to examine relationships between phthalate exposure and outcomes related to childhood asthma exacerbation. We used measures of phthalate metabolites and respiratory health measures including fractional exhaled nitric oxide (FENO), the Asthma Control Test (ACT), caregiver report of symptoms, and urinary leukotriene E₄ (uLTE₄) to estimate longitudinal associations using mixed effects models, adjusted for covariates. For 100% (i.e., doubling) increases in mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono-2-ethylhexyl phthalate (MEHP), and mono-ethyl phthalate (MEP), concentrations of FENO increased by 8.7% (95% CI: 0.7-17.3), 7.2% (95% CI: 0.0-14.9), and 6.4% (95% CI: 0.0-13.3), respectively. All phthalate metabolites demonstrated associations with uLTE₄, effect sizes ranging from an 8.7% increase in uLTE₄ (95% CI: 4.3-12.5) for a 100% increase in MEHP to an 18.1% increase in uLTE₄ (95% CI: 13.3-23.1) for a 100% increase in MNBP. In models of caregiver report of symptoms, no phthalate metabolites were significantly associated in primary models. No phthalate metabolites were associated with standardized ACT score. Our results suggest urinary phthalate metabolites are significant predictors of inflammatory biomarkers related to asthma exacerbation in children but not child and caregiver report of airway symptomatology.

Environmental exposures: evolving evidence for their roles in adult allergic disorders

PURPOSE OF REVIEW

Allergic disorders are the result of complex interactions between genetic predisposition and environmental exposures. Elucidating how specific environmental exposures contribute to allergic diseases in adults is crucial, especially as the world population ages in a rapidly changing environment.

RECENT FINDINGS

The effects of environmental exposures on allergic diseases remain understudied in adults. Although epidemiological studies suggest various environmental exposures are associated with the development and exacerbation of allergic diseases, further longitudinal studies are needed across various age groups in adults to pinpoint the exposures of concerns and the time windows of susceptibility. Mechanistic studies in adults are few. A multicomponent strategy targeting several allergens has been conditionally recommended for asthma, but recent findings on mitigation strategies remain limited.

SUMMARY

Further research on how environmental exposures cause and exacerbate allergic disorders is needed in adults, particularly across disease phenotypes. The effects of mitigation strategies against environmentally induced adult allergic diseases remain large research gaps. A better understanding of how and which environmental exposures contribute to allergic disorders is necessary to identify patients who are at higher risk and would benefit from specific interventions.

Indoor Microbial Exposures and Chronic Lung Disease: From Microbial Toxins to the Microbiome

Effects of environmental microbial exposures on human health have long been of interest. Microbes were historically assumed to be harmful, but data have suggested that microbial exposures can modulate the immune system. We focus on the effects of indoor environmental microbial exposure on chronic lung diseases. We found contradictory data in bacterial studies using endotoxin as a surrogate for bacterial exposure. Contradictory data also exist in studies of fungal exposure. Many factors may modulate the effect of environmental microbial exposures on lung health, including coexposures. Future studies need to clarify which method of assessing environmental microbial exposures is most relevant.

Low doses of Bisphenol A have pro-inflammatory and pro-oxidant effects, stimulate lipid peroxidation and increase the cardiotoxicity of Doxorubicin in cardiomyoblasts

Endocrine disrupters are strictly associated to cancer and several cardiovascular risk factors. Bisphenol A (BPA) is an endocrine disrupter commonly used in the manufacturing of plastics based on polycarbonate, polyvinyl chloride and resins. Our study aims to investigate whether BPA may cause pro-oxidative and pro-inflammatory effects on cardiomyoblasts, thus exacerbating the Doxorubicin (DOXO)-induced cardiotoxicity phenomena. We tested the metabolic effects of BPA at low doses analyzing its affections on the intracellular calcium uptake, oxidative stress, lipid peroxidation and production of nitric oxide and interleukins. Co-incubation of BPA and DOXO significantly reduced the cardiomyoblast viability, compared to only DOXO exposure cells. The mechanisms underlying these effects are based on the stimulation of the intracellular calcium accumulation and lipid peroxidation. Notably, BPA increase the production of pro-inflammatory interleukins involved in cardiovascular diseases as well as in DOXO-Induced cardiotoxicity phenomena. This study provides a rationale for translational studies in the field of cardio-oncology.

Prenatal high molecular weight phthalates and bisphenol A, and childhood respiratory and allergic outcomes

BACKGROUND

The prevalence of asthma and allergy is increasing in US children. In utero exposure to chemicals used in personal care products and plastics may contribute to increase in these diseases.

METHODS

We quantified urinary concentrations of eight phthalate metabolites and bisphenol A in mothers twice during pregnancy in 1999-2000 in Salinas, California. We assessed probable asthma, aeroallergies, eczema, and spirometry in their children at age 7, and measured T helper 1 and T helper 2 cells in blood at ages 2, 5, and 7 (N = 392). We employed Bayesian model averaging to select confounders from additional biomarkers measured in this population and controlled for them in logistic and linear regressions.

RESULTS

Monocarboxyisooctyl phthalate was associated with increased odds for probable asthma (odds ratio: 1.54, 95% CI: 1.12, 2.12), and with lower forced expiratory volume in one second (β: -0.09 L, 95% CI: -0.15, -0.03) and forced expiratory flow from 25% to 75% of forced vital capacity (β: -7.06 L/s, 95% CI: -11.04, -2.90). Several other associations were attenuated in final models that controlled for additional biomarkers.

CONCLUSION

Monocarboxyisooctyl phthalate was associated with lower respiratory health after controlling for related chemical exposure, which suggests that confounding by multiple chemical exposures should be considered in future research.