Photolysis of parabens using medium-pressure mercury lamps: Toxicity effects in MCF7, Balb/c 3T3 cells and Ceriodaphnia dubia

Author(s)

Gomes, Francisco E. R. ^[1] ; Bergo, Patricia L. S. ^{[2, 3]} ; Trap, Marilia A. ^[2] ; Spadoto, Mariangela ^[4] ; Galinaro, Carlos A. ^[3] ; Rodrigues-Filho, Edson ^[2] ; Leitao, Andrei ^[3] ; Tremiliosi-Filho, Germano ^[3]

Affiliation

^[1] Fed Inst Educ Sci & Technol Mato Grosso, BR-78850000 Primavera Do Leste, MT - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem, CP 676, BR-13565905 Sao Carlos, SP - Brazil

^[3] Univ Sao Paulo, Sao Carlos Inst Chem, Av Trabalhador Sao Carlense 400, CP 780, BR-13560970 Sao Carlos, SP - Brazil

^[4] Univ sao Paulo, Sao Carlos Engn Sch, Av Trabalhador Sao Carlense 400, BR-13560970 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Chemosphere; v. 208, p. 325-334, OCT 2018.
• Web of Science Citations: 4

Abstract

Degradation studies of the propylparaben (PrP), butylparaben (BuP) and of the propylparaben-butylparaben mixture (PrP-BuP) in deionized water and surface river water was investigated as a function of pH and initial concentration of the reactants using a medium-pressure mercury lamp. The photolysis of parabens (concentration ranging from 5 to 30 mg L-1) followed apparent pseudo-first-order kinetics, with rate constants (k) in deionized water and surface river water changed from 1.80 x 10(-1) to 3.68 x 10(-2) min(-1) and 1.43 x 10(-1) to 1.45 x 10(-2) min(-1), respectively. Degradation reaction was faster at pH 5 in comparison with pH 7 or 11. The photolysis of parabens was greater than 91%, with low mineralization (26.15%) observed in acidic medium after 95 min. Analysis by chromatography coupled to mass spectrometry (LC-MS/MS) showed that only one product was generated during the degradation reaction and has UV bands similar to 3,4-dihydroxybenzoic acid. Estrogenic activity tests showed that non degraded parabens stimulated the growth of breast adenocarcinoma (MCF-7) cells and this effect was evaluated after the photolysis. Cytotoxicity assays using fibroblasts cells (Balb/C 3T3 clone A31) indicated that the parental compounds and degradation products were not cytotoxic. On the contrary, non-degraded parabens were toxic to Ceriodaphnia dubia, but the product of photolysis was not. Overall, the photolytic method presented was able to degrade these parabens providing safe and non-estrogenic reaction product. (C) 2018 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 11/24137-0 - Method development and validation for standardization of Morus spp. leaves extracts and evaluation of biological activity of phytotherapic formulation for climacteric symptoms treatment
• Grantee: Patrícia Luísa de Souza Bergo
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 11/07025-3 - In silico studies and cell-based assays to identify new therapeutic approaches to prostate cancer
• Grantee: Andrei Leitão
• Support Opportunities: Regular Research Grants