Determination of polybrominated diphenyl ethers (PBDEs) in foods commercialized in Brazil employing microextraction by packed sorbent (MEPS) and daily intake estimated

Author(s)

Marilia Cristina Oliveira Souza

• Document type: Doctoral Thesis
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Ciências Farmacêuticas de Ribeirão Preto (PCARP/BC)
• Defense date: 2019-03-15

Examining board members

Fernando Barbosa Junior; Leandro Augusto Calixto; Paulo Clairmont Feitosa de Lima Gomes; Isarita Martins; Maria Eugenia Queiroz Nassur; Jonas Augusto Rizzato Paschoal

• Advisor: Fernando Barbosa Junior; Bruno Alves Rocha

Abstract

Polybrominated diphenyl ethers (PBDEs) are compounds classified as flame retardants and are persistent organic pollutants. These compounds are used in several products to increase fire and high temperatures resistance. The occurrence of potential human health effects after exposure has become a great concern due to the increase of PBDE concentration in the environment. Diet is considered the most important source of exposure to PBDEs, and food samples should be monitored to evaluate the contamination. However, the routine determination of these contaminants in a complex matrix, such as food samples, requires a simple, rapid and sensitive method compatible with the low concentrations found. In this sense, the present study proposes a new method combining the microextraction by packed sorbent (MEPS) and the gas chromatography coupled to mass spectrometry to determine 7 PBDEs (BDE-28, BDE-47, BDE-99, BDE- BDE-153, BDE-154, and BDE-183) in food samples of animal origin and with high lipid content, including egg, fish, seafood, and milk. So, the proposed method presents the following advantages: (i) -reduces the amount of sample required in the analyzes (50 and 100 mg of lyophilized sample); (ii) reduces solvent consumption; (iii) improves the detection limits (9 ng/g lipid in egg, 2 ng/g in fresh fish, and 1.5 ng/g in fresh milk), and ensures a great reproducibility and repeatability, high recovery values and absence of matrix effect. After the analytical validation step, the method was applied to the analysis of 123 different samples. The BDE-47 was the congener that presented the highest percentage of detection among all PBDEs analyzed. The sum of the mean concentrations (?PBDEs) of all the analyzed congeners was 18.1 ng/g lipid in egg samples, 26.4 ng/g in fresh fish, 25.6 ng/g in fresh seafood, and 39.9 ng/g in fresh milk. The concentrations determined in the samples of this study were higher than those found in samples from European countries and from the United States. Based on these results, this study suggests that the high concentrations found can be justified by the absence of legislation in Brazil regarding the use of PBDEs and the maximum amount allowed in food and environmental samples. Considering the results obtained for PBDE concentrations in the samples and the average food consumption in Brazil, the PBDEs estimate daily intake (EDI) for Brazilian population was calculated, and the total EDI was 31.9 ng/kg body weight - day. Indeed, the value of 0.356 for hazard index (HI) was estimated based on the reference dose values (BDE-47, BDE-99, and BDE-153). The EDI presented high values in relation to other studies described in the literature and the HI value was less than 1. The results suggest that the cumulative risk of exposure to PBDEs may be underestimated since only three PBDEs and four different types of food were included in the calculation. Therefore, a more detailed risk assessment to estimate the potential Brazilian health damage is of great importance (AU)

• FAPESP's process: 15/19665-8 - Determination of the main representatives of polybrominated diphenyl ethers class (PBDEs) in fish, eggs and milk employing microextraction packed sorbent (MEPS) and gas chromatography coupled with mass spectrometry (GC-MS)
• Grantee: Marília Cristina Oliveira Souza
• Support Opportunities: Scholarships in Brazil - Doctorate