Perspectives on Assessment of Risks from Dermal Exposure to Polycyclic Aromatic Hydrocarbons
Rhoda G. M. Wang, James B. Knaak, Howard I. Maibach in Health Risk Assessment, 2017
Polycyclic aromatic hydrocarbons (PAHs) are a diverse class of chemicals characterized by two or more fused aromatic rings that contain only carbon and hydrogen atoms. PAHs find their way into the environment primarily by the incomplete combustion of organic materials. Because combustion of organic materials occurs in such diverse settings throughout society, PAHs are ubiquitous. Polycyclic aromatic hydrocarbons are released into the environment in a number of common materials, including soot, coal tar, tobacco smoke, petroleum, air pollutants, and cutting oils (Klaassen et al., 1986; page 172). They are found in wood smoke, gasoline and diesel exhaust, and are synthesized by some plants, including human food crops (International Agency for Research on Cancer (IARC), 1983). From such sources, PAHs easily reach air, water, soil, sediments, and aquatic organisms. Exposure to PAHs is extensive in modern, industrialized countries.
Multistep Carcinogenesis and Human Epithelial Cells
George E. Milo, Bruce C. Casto, Charles F. Shuler in Transformation of Human Epithelial Cells: Molecular and Oncogenetic Mechanisms, 2017
Certain carcinogenic polycyclic aromatic hydrocarbons have been identified in our environment, and some chemicals or radiation are known definitely to cause cancer in human. Since it is estimated that 80% of human cancers are epithelial in origin, the human epithelial cell system described here may be a useful in vitro tool for screening potential carcinogenic agents. The molecular mechanisms of chemical or radiation-induced neoplastic transformation of human epithelial cells are poorly understood. Studies to identify the genes that are differentially expressed and to characterize activated transforming genes or suppressor genes during in vitro transformation by chemicals or irradiation are in progress. Analysis of the expression of known transforming genes in these transformed human epithelial cells are also in progress.
Environment, pregnancy complications, and omics
Moshe Hod, Vincenzo Berghella, Mary E. D'Alton, Gian Carlo Di Renzo, Eduard Gratacós, Vassilios Fanos in New Technologies and Perinatal Medicine, 2019
During its development, the central nervous system is highly susceptible to external stimuli that may exert a deleterious impact. Several industrial chemicals, such as lead, arsenic, and pesticides, have been associated with causing neurotoxicity (29). Maternal exposure during pregnancy to indoor environmental pollutants, such as mold and pesticides, has also been suggested to impair fetal neurologic development and cognitive function (30). Data from six European birth cohorts, including 9,482 children, demonstrated an association of exposure during pregnancy to air pollutants, particularly NO2, with reduced psychomotor development (global psychomotor development score decreased by 0.68 points [95% CI = −1.25 to −0.11] per increase of 10 μg/m3 in NO2) (31). A prospective Polish study showed an association of exposure to polycyclic aromatic hydrocarbons, which are indoor and outdoor air pollutants that result from industrial combustion, home cooking, and cigarette smoking, with impaired cognitive development in children, 5 years of age, following in utero exposure (32).
The induction of aryl hydrocarbon receptor (AHR) in immune organs of developing chicks by polycyclic aromatic hydrocarbons
Published in Toxicology Mechanisms and Methods, 2018
A. R. Nisha, H. Hazilawati, M. L. Mohd Azmi, M. M. Noordin
Polycyclic aromatic hydrocarbons are ubiquitous and persistent organic pollutants characterized by the presence of fused aromatic rings. They are formed by the incomplete combustion of organic materials and fossil fuels (Okedeyi 2012); hence the most predominant air pollutant (El-Shahawi et al. 2010). The global emission of the 16 PAHs listed by the United States Environmental Protection Agency as priority pollutants was approximately 520 000 tons in 2004 (Zhang and Tao 2009). When inhaled, PAHs bind to their ligands to form the AHR complex which then associates with the AHR nuclear translocator protein (McIntosh et al. 2010). The transformed complex binds to xenobiotic responsive elements in responsive genes and turns on their transcription. These genes encode enzymes involved in the metabolism (Hankinson 1995; Pohjanvirta 2011), bioactivation to reactive metabolites (Ma and Lu 2007) and genotoxicity (Baird et al. 2005). The effects of PAHs on the immune system of various animals and models have been studied for the last 30 years. Despite these efforts, the mechanism or mechanisms by which PAHs exert their effects on the immune system are still unknown. Hence the study was done in an effort to find out the correlation between PAH toxicity and AHR activation in developing chicks by isolation and identification of AHR mRNA transcript thymus, bursa of Fabricius and spleen of developing chicks. This study also aims to interpret the correlation between AHR activation and dose of PAHs.
Removal efficiency of PAH’s from five wastewater treatment plants in Jordan
Published in Toxin Reviews, 2018
Mahmoud A. Alawi, Ibrahim N. Tarawneh, Zahra’ Ghanem
Jordan is one of the developing countries that have shortage of water resources; it is among the lowest per capita worldwide and the water scarcity is the most important natural constraint of its economic growth and development (Batarseh et al., 2003). The treated water is a potential solution for addressing the problems of poor quantity and quality of water in this region (Al-Khashman et al., 2013). This study took a number of samples of effluent, influent and sludge from five wastewater treatment plants in Jordan to study the removal efficiency polycyclic aromatic hydrocarbons (PAH’s), which is considered as one of the persistence organic pollutants (POP’s) in the environment. Polycyclic aromatic hydrocarbons are hazardous organic compounds, considered as one of the most important environmental pollutants, they consist of two or more benzonid groups formed at high temperature during the incomplete combustion of organic matter, they are found in the environment in air, water, soil and food. PAH’s have carcinogenic and mutagenic effect on human body, so a systematic monitoring is applied in most countries worldwide (Ramos et al., 2012; Torretta, 2012; Torretta & Katsoyiannis, 2013).
In vitro effects of combustion generated carbon dots on cellular parameters in healthy and cancerous breast cells
Published in Nanotoxicology, 2022
Nikita Dinger, Valeria Panzetta, Carmela Russo, Paolo Antonio Netti, Mariano Sirignano
Our group recently presented a simple and economic synthesis route with a one-step controllable production of tunable luminescent CDs in fuel rich combustion reactors (Russo, Apicella, and Ciajolo 2019; Russo et al. 2023). In fact, fossil fuels might emit in the conditions of incomplete combustion gaseous by-products such as high molecular weight polycyclic aromatic hydrocarbons (PAHs) and particulate matter (Bockhorn 1994). This carbonaceous particulate is characterized by a bimodal size distribution: nanoparticles in the range 1–5 nm, and soot particles from 10 to 100 nm (D’Anna 2009; Mahrt et al. 2017; Michelsen et al. 2020; H. Wang 2011). Small nanoparticles are mainly generated in a process termed nucleation and are constituted of organic carbon—namely, a moiety of different PAHs—arranged in stacks and loose structure of molecules held by van der Waals interactions and crosslinking bonds (C. S. Wang et al. 2017). At flame conditions, these small nanoparticles are mainly visible-transparent and do not emit any significant incandescent or visible radiation (D’Anna 2009). However, both at flame temperature and at room temperature, these nanoparticles exhibit a strong fluorescence upon light excitation (Sirignano et al. 2017). Another peculiar characteristic of these small nanoparticles is their high surface area to mass ratio (Pedata et al. 2015). For these reasons, these small nanoparticles can be ascribed to the class of CDs.
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