Browsing by Author "Pinho, Carina"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- Analysis of total extractable hydrocarbons in environmental water samples. Implementation and validation of a FT-IR methodPublication . Pinho, Carina; Melo, Armindo; Mansilha, Catarina; Gameiro, Paula
- Bisphenol A migration from plastic materials: direct insight of ecotoxicity in Daphnia magnaPublication . Mansilha, Catarina; Silva, Poliana; Rocha, Sónia; Gameiro, Paula; Domingues, Valentina; Pinho, Carina; Ferreira, IsabelBisphenol A (BPA) is an endocrine disrupting chemical (EDC) whose migration from food packaging is recognized worldwide. However, the real overall food contamination and related consequences are yet largely unknown. Among humans, children exposition to BPA contamination has been emphasized because the immaturity of their biological systems. The main aim of this study was to assess the reproductive burden of BPA leached from commercially available plastic containers used or related to child nutrition, performing ecotoxicological tests using the biomonitoring specie Daphnia magna. Acute and chronic tests, as well as single and multigenerational tests were done. Migration of BPA from several baby bottles and other plastic containers evaluated by GC-MS indicated that a broader range of foodstuff may be contaminated when packed in plastics. Ecotoxicological tests results performed using defined concentrations of BPA were in agreement with literature, although a precocious maturity of daphnids was detected at 3.0 mg/L. Curiously, an increased reproductive output (embryos per female) was observed when daphnids were bred in the polycarbonate (PC) containers (145.1±4.3% to 264.7±3.8%), both in single as in multigenerational tests, in comparison with the negative control group (100.3±1.6%). A strong correlated dose-dependent ecotoxicological effect was observed, providing evidence that BPA leached from plastic food packaging materials act as functional estrogen in vivo at very low concentrations. In contrast, embryo production by daphnids cultured in polypropylene and non-PC bottles, was slightly but not significantly enhanced (92.5±2.0% to 118.8±1.8%). Multigenerational tests also revealed magnification of the adverse effects, not only on fecundity but also on mortality, which represents a worrying trend for organisms that are chronically exposed to xenoestrogens for many generations. Two plausible explanations for the observed results could be given: a non-monotonic dose-response relationship or a mixture toxicity effect.
- Occurrence of Bisphenol A, Estrone, 17β-Estradiol and 17α-Ethinylestradiol in Portuguese RiversPublication . Rocha, Sónia; Domingues, Valentina F.; Pinho, Carina; Fernandes, Virgínia C.; Delerue-Matos, Cristina; Gameiro, Paula; Mansilha, CatarinaThis study focused on the occurrence of several EDCs including bisphenol A, estrone (E1), the 17b-estradiol (E2) and 17a-ethinylestradiol (EE2) in fourteen rivers of Portugal. Samples analysis revealed a widespread contamination of BPA especially in Ave, Ca´vado, Douro, Ferro, Sousa and Vizela Rivers. Achieving 98.4 ng/L for the highest concentration. The estrogens achieved above the method quantification limit (MQL) were E1 in A ´ gueda River and E2 in Ave, Lima and Taˆmega Rivers. The maximum concentration detected for E1 was 26.9 ng/L. EE2 was detected only below MQL.
- Optimization of conditions for anthocyanin hydrolysis from red wine using response surface methodology (RSM)Publication . Pinho, Carina; Mansilha, Catarina; Gameiro, PaulaOptimization of conditions for anthocyanin hydrolysis from red wine was investigated using response surface methodology. The aglycon forms of the anthocyanins were quantified by high-performance liquid chromatography with diode array detection. The combined effects of three independent variables, HCl amount, heating temperature, and hydrolysis time, were studied using a 2(3) full-factorial central composite design. Anthocyanin hydrolysis yield depended mainly on the heating temperature and time of hydrolysis. HCl amount was the factor that least influenced the hydrolysis of anthocyanins. From experimental results, the maximum yield of anthocyanidins was reached with 9.8 mL of HCl (32% v/v), a heating temperature of 166.2 °C, and a hydrolysis time of 46.6 min. Five anthocyanidins, namely, delphinidin, cyanidin, petunidin, peonidin, and malvidin, were quantified in red wine. The reliability of the method was confirmed by recovery experiments, performed under optimal conditions. Recoveries indicated that anthocyanidins resisted the hydrolysis conditions.