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Environmental Inhaled Agents and Their Relation to Lung Cancer
Published in Jacob Loke, Pathophysiology and Treatment of Inhalation Injuries, 2020
The metabolic activation of the carcinogen benzo(a)pyrene is one of the best studied. Human bronchus has been shown to metabolize benzo(a)pyrene into various metabolites, in particular the reactive diolepoxide 7, 8-dihydro-7, 8-dihydroxybenzo(a)pyrene 9, 10-oxide, which can bind to DNA of bronchus by covalent bonds and possibly initiate tumor formation (Cohen, 1981).
Effect of tomato juice on the sperm quality of mice exposed to tertiary cigarette smoke
Published in Ade Gafar Abdullah, Isma Widiaty, Cep Ubad Abdullah, Medical Technology and Environmental Health, 2020
A.R. Furqaani, A.K. Sari, R. Ekowati, L.H. Siswanti, A. Triamullah, T. Sugiartini
Dai and colleagues (2015) have shown that toxins in cigarettes are compounds that play a role in activating the oxidative stress mechanism so that there is an increase in free radicals in the body. This free radical increase is positively correlated with DNA fragmentation and damage. Benzo(a)pyrene (B[a]P) found in cigarette smoke is mutagenic and carcinogenic. The compound will bind with DNA covalently to form a DNA adduct called benzo(a)pyrene diol epoxide-DNA (BPDE-DNA). It is known that BPDE-DNA increases in smokers and significantly decreases the percentage of halo acrosomes and is a contributing factor of DNA damage in smokers’ sperm (Hammadeh et al. 2016). Increasing environmental pollutants, including cigarette residues, expose humans to various substances that threaten health. Therefore, people need to change their lifestyle and consume food and nutrients that can minimize these adverse effects.
Quality Assurance, Validation, and Peer Review
Published in Samuel C. Morris, Cancer Risk Assessment, 2020
Replication is one bulwark of science. Particularly in the physical sciences, publication of an important new discovery leads to a rush in other laboratories to repeat or replicate the experiment. This redundancy and duplication, so often decried by bureaucrats and congressmen, provides credibility and assurances that the original findings were real, and not an artifact of the local experimental set-up or other anomaly. Moreover, the essence of scientific results is that they can be replicated if the same circumstances are recreated. In biology, experiments are less frequently replicated, partly due to time and expense. Because of greater random variation in biology, even exact replications cannot be expected to give the same results. Nonetheless, closely related studies with similar findings greatly increase the value of information. One of the reasons that benzo[a]pyrene is so well understood and so frequently cited as an example of chemical carcinogenesis is that there have been many experiments and studies with this one substance. When in vitro tests, animal studies and epidemiology all show a chemical to be a carcinogen, there is little question left.
Polycyclic aromatic hydrocarbons in soil situated around solid waste dumpsite in Awka, Nigeria
Published in Toxin Reviews, 2023
Chiedozie C. Aralu, Patrice-Anthony C. Okoye, Kovo G. Akpomie, Helen O. Chukwuemeka‐Okorie, Hillary O. Abugu
The most carcinogenic PAH, Benzo(a)pyrene recorded concentrations ranging from ND to 0.45 µg/kg for the study area and 0.37–0.58 µg/kg for the control area. The total PAHs recorded from this analysis were lower than previous reports (Nasrollahzadeh et al. 2012, Alawi and Azeez 2016). Benzo(g,h,i)perylene levels reported were all lesser than previous studies (Popenda and Włodarczyk-Makuła 2018, Włodarczyk-Makuła et al. 2018). When comparing the total levels of PAHs in the soil samples, it was found that soil close to a dumpsite in previous studies were higher than the values obtained in this study 0.1049–5.1662 mg/kg (Okechukwu et al. 2021), 10–1200 µg/kg (Shitandayi et al. 2019), 30.036–60.958 mg/kg (Ekpete et al. 2019), 1756–2224 μg/Kg (Adeyi and Oyeleke, 2017), 11.0– 41.6 mg/Kg (Olufunmilayo et al. 2015), 0.94–2.79 mg/kg (Oketola and Akpotu, 2015), and 25.8–7380 μg kg (Wang et al. 2015). The total levels of PAHs obtained in this study were higher than previously recorded work (Mustapha et al. 2019).
The association between urinary polycyclic aromatic hydrocarbon metabolites and atopic triad by age and body weight in the US population
Published in Journal of Dermatological Treatment, 2022
Sooyoung Kim, Kathryn A. Carson, Anna L. Chien
A number of geographic studies have demonstrated that air pollutants are risk factors for the development of atopic dermatitis. Lee et al. found that flexural eczema was associated with nitrogen oxides (NOx) and carbon monoxide (CO) in Taiwanese children going to school within 2 km of 55 stations (29). A prospective cohort study during the first six years of life in Munich demonstrated strong positive associations between eczema and distance to main roads (30). In another study, eczema symptoms in 9–11 year old children were associated with exposure to three year averaged concentrations of air pollutants (NOx, CO, PM10, and benzene) (31). Our findings added evidence for the association between air pollution and atopic dermatitis. 1-PYR and 3-PHE increased the risk of chronic pruritus in elderly patients. Also, the risk of chronic pruritus increased with higher levels of 2-PHE among overweight people. 1-PYR is a biomarker of total exposure of PAH and specifically represents the higher molecular weight pyrene (32). It was reported that repeated exposure to high concentrations of PAHs, especially semi-volatile pyrene during 5–6 years of age and prenatal period was associated with asthma in children (33). The exposure to pyrene induced the production of IL-4 and enhanced allergic IgE responses in mice (34). 1-PYR was reported to be positively associated with clinical inflammatory parameters including total white blood cell count and serum C-reactive protein (35).
Placental levels of polycyclic aromatic hydrocarbons (PAHs) and their association with birth weight of infants
Published in Drug and Chemical Toxicology, 2022
Priyanka Agarwal, Madhu Anand, Paromita Chakraborty, Laxmi Singh, Jamson Masih, Ajay Taneja
Table 2 summarizes the descriptive statistics of PAHs congeners. The total concentration of PAH quantified in placenta tissue samples ranged from 0.64–1363.33 µg/L, with a mean value of 97.20 µg/L (wet-weight concentration levels). Among the sixteen congeners analyzed, the highest levels of chrysene (36.92 µg/L) and benzo(k)fluoranthene (34.82 µg/L) were observed. Pearson’s correlation analysis revealed that chrysene and benzo(k)fluoranthene had a strong correlation with the concentrations of other PAHs and ∑PAHs as well (Pearson correlation coefficient, r = 0.27–0.99, Supplementary file S2). The detection rates were different for the individual PAHs with highest PAHs detected as follows: benzo(k)fluoranthene (44%), benzo(a)anthracene (43%) and benzo(b)fluoranthene (41%), while the lowest detection rate was observed for acenaphthene and fluorene (4–8% of total samples analyzed). Benzo(a)pyrene, a known human carcinogen, was detected in 27.4% of the samples. It was also observed during the study that high molecular weight PAHs (HMW: Fla, Pyr, BaA, Chy, BbF, BkF, BaP, DahA, IcdP, BghiP) were more abundant than low molecular weight PAHs (LMW: Nap, Ace, Acy, Flu, Phen, Anth) in the analyzed samples. The ratio of ∑LMW PAHs to ∑HMW PAHs (LMW/HMW) is commonly used to recognize the emission sources of PAHs in the atmosphere. In the current study, the ratio of ∑LMW/HMW < 1, clearly points that in placental tissue samples, the main source of PAHs is mostly pyrogenic.