Makanan berpanggang sebabkan barah

https://academic.oup.com/toxsci/article/145/1/5/1627571

IMPLICATIONS FOR HUMAN HEALTH

There is great variability among different PAHs with respect to carcinogenic potency and their dose-response relationships (Deutsch-Wenzel et al., 1983; Grimmer et al., 1988). Moreover, in reality, the environmental PAHs often exist as mixtures. Tarantini et al. (2011) reported that the components in PAH mixtures can affect the carcinogenicity of each PAH, by exhibiting synergistic and antagonistic effects, often simultaneously. This finding complicates the evaluation of cancer risk for PAHs. Recently Cioroiu et al. (2013) assessed PAHs in the lungs of 31 patients with lung cancer in Romania. Fifteen PAHs were detected, of which benz[a]anthracene, anthracene, fluoranthene, BaP, benzo[b]fluoranthrene, benzo[k]fluoranthrene were considered the major components of the mixture (Fig. 2). This study is the first to record PAH concentrations in human lung cancer tissue, and indicates that lung cancer patients present high concentrations of carcinogenic (0.33–31.94 ng/g wet tissue, mean = 6.12 ±7.31 ng/g wet tissue) and noncarcinogenic (2.46–218.19 ng/g wet tissue, mean = 45.57 ± 54.83 ng/g wet tissue) PAHs in lung tissue, thereby providing strong evidence that PAHs are etiologic factors in lung cancer in humans. Further mechanistic studies of the relevant components of these mixtures, as well as the mixtures themselves, are needed to determine which component(s) (and which when combined), play a role in the etiology of lung cancer.

In conjunction with studying mixtures, quantitative cancer risk estimates of PAHs are highly uncertain because of the lack of good-quality data. According to the World Health Organization Air Quality Guidelines for Europe, the unit risk is 9 × 10⁻⁵ per ng/m³ of BaP as an indicator of the total PAH content, namely, lifetime exposure to 0.1 ng/m³ would theoretically lead to 1 extra cancer case in 100 000 exposed individuals. This concentration of 0.1 ng/m³ of BaP is suggested as a health-based guideline. Because the carcinogenic potency of fluoranthene has been estimated to be ∼20 times less than that of BaP, a tentative guideline value of 2 ng/m³ is suggested for fluoranthene. Guidelines still need to be determined for other significant PAHs such as phenanthrene, methylated phenanthrenes/anthracenes and pyrene, and large-molecule PAHs such as dibenz[a,h]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and indeno[1,2,3-cd]pyrene. Thus, it is only through careful mechanistic studies that recommendations can be provided in support of these guidelines.

https://academic.oup.com/toxsci/article/145/1/5/1627571

In conclusion, this review focuses on the mechanisms of toxicity of PAHs, in relation to pulmonary carcinogenesis in humans. To tease the mechanistic effects of multiple PAHs will require an inter-disciplinary approach with systems biologists, epidemiologists, pathologists, omics researchers, mechanistic researchers, and biostatisticians who can analyze complex data sets. PAHs are a complex mixture, often with over 100 components, making these compounds difficult to study. The most well-known PAH, BaP, is just the beginning of our understanding of the components of these mixtures. Further research is needed on how individual or binary and higher order mixtures of PAHs induce genetic and molecular alterations. To add to the complexity, these mixtures should be investigated in susceptible populations such as those with genetic polymorphisms as well as in sensitive populations such as children. This research will lead to novel strategies for the prevention and/or treatment of human lung carcinogenesis mediated by environmental PAHs

https://academic.oup.com/toxsci/article/145/1/5/1627571