RESUMO

A risk assessment was performed to estimate the lead (Pb) dietary intake in the Brazilian population. Data on Pb concentration in food were obtained through a systematic review with meta-analyses and from the GEMS/Food database, both involving data through 2018. Food consumption data were obtained from a Brazilian official dietary survey. Pb dietary intakes were estimated by a deterministic approach. Risk characterisation was conducted using the margin of exposure approach (MOE). The total Pb intake in the Brazilian population ranged from 1.53 to 2.01 µg/kg bw/day. Major contributors to Pb dietary exposure were the vegetable and vegetable products and beverage categories. From the results obtained, a risk of increased systolic pressure, nephrotoxicity and decrease of 0.5 point intelligence quotient can be expected, MOE<1, with greater magnitudes of risk observed for men in rural areas and in the Midwest, Southeast and South Brazilian regions. The dietary risk assessment indicates a health concern for the Brazilian population associated with Pb dietary intake.

Assuntos

RESUMO

The aim of this paper was the validation of a methodology for determination of L-phenylalanine (Phe) in wheat fl our by second derivative spectrophotometry. For this purpose, 0.525g of wheat flour was hydrolyzed with HCl 5.7 mol/L at 110C for 24 h. This material was diluted to 50 mL with 0.1 mol/L sodium phosphate buffer, pH 7.0. The solutions prepared from this hidrolyzed were measured on UV/VIS spectrophotometer at wavelength range from 230 nm to 280 nm. The second derivative spectrophotometrys spectra were plotted and the values of the negatives peaks areas were used for estimating the Phe contents. Linearity was demonstrated in the range of 0.010 mg/mL to 0.035 mg/mL (corresponding to 251 mg/100g to877 mg/100g of Phe in flour). Matrix effects were observed. The Phe determination was not affected by similar compounds such as L-tyrosine and L-tryptofan. The recoveries ranged from 81 % to 118 % and the relative standard deviation under repetitivity and within-reproducibility conditions were 11 % and 15 %, respectively, for samples at 354 mg/100g, showing the adequate recovery and precision of the methodology. The limits of detection and quantification were 63 mg/100gand 175 mg/100g, respectively. The studied parameters indicated that this methodology is suitable for monitoring and controlling of Phe contents in wheat flour.

O objetivo deste trabalho foi validar um método quantitativo para determinação de L-fenilalanina (Fen) em farinha de trigo por espectrofotometria derivada segunda. A amostra de farinha de trigo, na quantidade de 0,525g, foi submetida à hidrólise ácida com HCl a 5,7 mol/L, a 110 C, por 24 h. O material hidrolisado foi reconstituído para 50 mL com tampão fosfato de sódio a 0,1 mol/L, pH 7,0. As soluções preparadas a partir dessa amostra foram submetidas às leituras de absorvância, entre 230 nm e 280 nm, em espectrofotômetro UV/VIS. Os espectros de derivada segunda foram traçados e os valores das áreas dos picos negativos foram utilizados para estimar os teores de Fen. A linearidade do método foi demonstrada na faixa de 0,010 mg/mL a 0,035 mg/mL (correspondente a teores de 251 mg/100g a 877 mg/100g de Fen em farinha de trigo). Efeitos de matriz foram observados. A determinação de Fen não sofreu interferência de compostos como L-tirosinae L-triptofano. As porcentagens de recuperação variaram de 81 % a 118 % e os desvios padrão relativos de repetitividade e reprodutibilidade parcial foram respectivamente 11 % e 15 %, para amostras contendo 354 mg/100g, demonstrando adequada recuperação e precisão do método. Os limites de detecção e quantificação foram, respectivamente, 63 mg/100ge 175 mg/100g. Os parâmetros de desempenho estudados indicaram adequação do método para o monitoramento