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Karlo Jurica, Natalija Uršulin-Trstenjak, Darija Vukić Lušić, Dražen Lušić and Zdenko Šmit

Ftalati su esteri ftalne kiseline i alifatskih alkohola koji se dodaju u plastične mase da bi se poboljšala njihova mekoća, savitljivost i rastezljivost. Zbog svojih fizičko-kemijskih svojstava ftalati su vrlo mobilni i lako migriraju iz plastičnih proizvoda u prostor koji ih okružuje, pa tako dospijevaju u okoliš te su stoga opasni za čovjeka.

U radu su ukratko opisana svojstva i raspodjela ftalata u okolišu, toksični učinci na ljudsko zdravlje te zakonska regulativa vezana uz maksimalno dopuštene koncentracije ftalata u vodi za piće i u proizvodima namijenjenima dojenčadi, kao i dopušteni dnevni unos u ljudski organizam. Posebna pažnja posvećena je metodama određivanja ftalata u alkoholnim pićima te razinama ftalata s osvrtom na njihovu pojavnost i koncentracije u šljivovici koja se proizvodi u Hrvatskoj. Obuhvaćena je i tematika vezana za ftalate u denaturiranom alkoholu i neregistriranom alkoholu koji se ilegalno stavlja na tržište.

U zaključku su navedene smjernice za učinkoviti nadzor nad putovima izloženosti ljudi ftalatima.

Open access

Irena Brčić Karačonji, Sonja Anić Jurica, Dario Lasić and Karlo Jurica

Abstract

Phthalates are esters of phthalic acid and aliphatic alcohol added to plastic to improve its softness, flexibility, and extensibility. They easily migrate from plastic products into the environment because of their physical and chemical properties. This review summarises their characteristics, distribution in the environment, monitoring, use, toxic effects on human health, regulatory limits in different matrices and products, and tolerable daily intake. The studies we have reviewed suggest that phthalates have a potential to affect reproduction and development in humans. Due to the inconsistent data, further studies are needed and, in the meantime, precautionary policies must be implemented. Here we draw attention to the methods of determining phthalate levels in alcoholic beverages and reported levels in plum spirits produced in Croatia. Legally produced and moderately consumed plum spirits do not seem to increase the risk of phthalate toxicity for human health. We conclude with recommendations for the effective monitoring of phthalate exposure in humans and for the implementation of alternative materials in alcohol production.

Open access

Karlo Jurica, Irena Brčić Karačonji, Vesna Benković and Nevenka Kopjar

Abstract

This study investigated the mechanisms of hydroquinone toxicity and assessed the relationships between its cytotoxic, genotoxic, and cytogenetic effects tested at 8, 140, and 280 μg mL-1 in human peripheral blood lymphocytes exposed for 24 h. The outcomes of the treatments were evaluated using the apoptosis/necrosis assay, the alkaline comet assay, and the cytokinesis-block micronucleus (CBMN) cytome assay. The tested hydroquinone concentrations produced relatively weak cytotoxicity in resting lymphocytes, which mostly died via apoptosis. Hydroquinone’s marked genotoxic effects were detected using the alkaline comet assay. Significantly decreased values of all comet parameters compared to controls indicated specific mechanisms of hydroquinone-DNA interactions. Our results suggest that the two higher hydroquinone concentrations possibly led to cross-linking and adduct formation. Increased levels of DNA breakage measured following exposure to the lowest concentration suggested mechanisms related to oxidative stress and inhibition of topoisomerase II. At 8 μg mL-1, hydroquinone did not significantly affect MN formation. At 140 and 280 μg mL-1, it completely blocked lymphocyte division. The two latter concentrations also led to erythrocyte stabilization and prevented their lysis. At least two facts contribute to this study’s relevance: (I) this is the first study that quantifies the degree of reduction in total comet area measured in lymphocyte DNA after hydroquinone treatment, (II) it is also the first one on a lymphocyte model that adopted the “cytome” protocol in an MN assay and found that lymphocytes exposure even to low hydroquinone concentration resulted in a significant increase of nuclear bud frequency. Considering the limitations of the lymphocyte model, which does not possess intrinsic metabolic activation, in order to unequivocally prove the obtained results further studies using other appropriate cell lines are advised.

Open access

Karlo Jurica, Irena Brčić Karačonji, Sandra Šegan, Dušanka Milojković Opsenica and Dario Kremer

Abstract

The phenolic glycoside arbutin and its metabolite with uroantiseptic activity hydroquinone occur naturally in the leaves of various medicinal plants and spices. In this study, an extraction procedure coupled with gas chromatography-mass spectrometry (GC-MS) was developed to determine arbutin and hydroquinone content in strawberry tree (Arbutus unedo L., Ericaceae) leaves. The method showed good linearity (R2>0.9987) in the tested concentration range (0.5-200 μg mL-1), as well as good precision (RSD<5 %), analytical recovery (96.2-98.0 %), and sensitivity (limit of detection=0.009 and 0.004 μg mL-1 for arbutin and hydroquinone, respectively). The results obtained by the validated GC-MS method corresponded well to those obtained by high performance liquid chromatography (HPLC) method. The proposed method was then applied for determining arbutin and hydroquinone content in methanolic leaf extracts. The amount of arbutin in the leaves collected on the island of Koločep (6.82 mg g-1 dry weight) was found to be higher (tpaired=43.57, tc=2.92) in comparison to the amount of arbutin in the leaves collected on the island of Mali Lošinj (2.75 mg g-1 dry weight). Hydroquinone was not detected in any of the samples. The analytical features of the proposed GC-MS method demonstrated that arbutin and hydroquinone could be determined alternatively by gas chromatography. Due to its wide concentration range, the method could also be suitable for arbutin and hydroquinone analysis in leaves of other plant families (Rosaceae, Lamiaceae, etc.).