The way food is prepared has the power to affect the population's exposure to polycyclic aromatic hydrocarbons (PAHs), substances primarily generated by the incomplete combustion of organic material. Common culinary techniques, such as baking, grilling, smoking, toasting, and frying, can promote the creation of these compounds, some of which are linked to cancer risk.
Due to a lack of information in Brazil on how to safely identify the presence of PAHs in food and regarding public exposure, a team of researchers from the Faculty of Pharmaceutical Sciences of Ribeirão Preto (FCFRP), affiliated with USP, conducted an analysis of the main scientific findings published on the subject between 2014 and 2024. This study aimed to point out the gaps in data generation concerning these contaminants in the national territory.
The research was conducted during Gabriel Henrique Savietto's master's degree, under the guidance of Professor Marília Cristina Oliveira Souza, and its results were published in the journal Food Additives & Contaminants Part A. The researcher explained that PAHs result from the incomplete combustion of organic matter, being lipophilic compounds, meaning they have a high affinity and ease of dissolving in fats, oils, and nonpolar solvents.
Savietto emphasized that this lipophilic property facilitates the accumulation of these contaminants in the human body, given that they are found in animal products, such as fish and other aquatic products.
The occurrence of PAHs during preparation is closely linked to the processing conditions applied. High temperatures, incomplete combustion, and the contact of fat with extremely hot surfaces are factors that can drive the formation of these compounds. The researcher mentioned that, in grilled foods, the dripping of fat onto the hot surface can contribute to the formation of these contaminants, which end up present in the final product.
One of the greatest health dangers lies in the carcinogenic potential of certain PAHs. However, Savietto clarified that simple exposure to the compounds does not guarantee cancer development; he warned that continuous exposure can increase the risk of diseases in various organs and is associated with changes in several bodily systems.
Therefore, the researcher advocates that educating the population about the existence and formation mechanisms of PAHs in food can reduce exposure. Changes in cooking habits can mitigate this formation. In the case of fried foods, the repeated use of oil at high temperatures also contributes to the increase in PAHs. For grilled foods, it is crucial to prevent fat from dripping directly onto very hot surfaces to reduce the incidence of these contaminants.
Thus, small adjustments in preparation procedures, such as controlling temperature and heating time, make a significant difference. Savietto reinforced that, in grilled items, direct contact with combustion products and the dripping of fat onto hot surfaces promote the formation of PAHs and, consequently, their presence in the finished food.
The studies revealed that, in Brazil, research on PAHs remains mainly concentrated in the South and Southeast regions, which hinders the analysis of contamination in food from other parts of the country. Researchers consider this fact an obstacle to understanding how different dietary patterns and processing methods impact contamination levels.
For Savietto, this disparity not only compromises the understanding of food safety but also exposes differences in monitoring and research structure among the various regions. He stated categorically: 'We cannot talk about food safety for the entire Country when the production of knowledge and monitoring of contaminants does not reach all regions equally.'
Despite the findings across various types of food, the lack of data prevents the precise determination of which products consumed in Brazil present the highest risk of contamination. The reviewed studies indicate higher concentrations of contaminants in items subjected to processes such as smoking, roasting, frying, and grilling. Fish and seafood, along with processed meats and processed foods, are among the evaluated products.
The Sanitary Surveillance Agency (Anvisa) is responsible for regulating PAHs in Brazil, but this regulation has restrictions. Currently, it focuses mainly on benzo[a]pyrene in certain food categories, while international standards, notably European ones, encompass more food groups and consider PAH4, which is a set of four PAHs used in risk and contamination assessment.
However, Savietto pointed out that legislation alone is not enough without an effective monitoring system. He informed that the article produced highlights crucial limitations in the inspection and monitoring of PAH contamination, citing the scarcity of data and the insufficient production of information to fully assess the levels of these contaminants in different regions and foods in the country. Furthermore, he mentioned the lack of standardization in laboratory analyses, which hinders the comparison of results and the elaboration of more solid risk assessments.
A total of 36 studies were considered for the analysis. The results showed that the situation is not alarming in cases of acute exposure, but the scenario changes drastically when considering chronic exposure, as the population may come into contact with contaminants through different foods over the years.
However, Savietto warns that it is still not possible to accurately quantify this long-term risk for the entire Brazilian population, making this a central point that needs to be addressed by future investigations, especially those expanding research to less studied areas.
