Study On Photodegradation Of Parabens And Their Chlorinated Byproducts In Environmental Water

Parabens are a series of broad-spectrum preservatives commonly used in foods,medicines,cosmetics and personal care products.For the past few years,they have been widely detected in various environmental waters due to their enormous utilization.Actually,parabens have been proved to be potential endocrine disrupting chemicals and there are a certain extent safety risks for the natural environment as well as the human frequently exposed to that.During current wastewater treatment process,it is easy to generate chlorinated parabens in chlorine disinfection and their toxicity and adverse effect on human health are more serious than the parent parabens.Therefore,in this paper we use ultraviolet-visible spectroscopy,high-performance liquid chromatography,and xenon light source to explore the photodegradation of parabens and their chlorinated byproducts under simulated solar illumination and in aqueous solution.Represented by MP,EP,MDHB and EDHB the four dissolved organic matter fulvic acid?FA?on photolysis of parabens and their chlorinated derivatives were researched systemically.According to the experiment results,there is no direct photolysis of in addition,the degradation rate enhances with the increase of the photosensitizer concentration within experimental range.In alkaline solution,the deprotonation of MP and EP is in favor of their indirect oxidation of hydroxyl radical.MDHB and EDHB can undergo direct photolysis under simulated sunlight,and NO₃^-has no effect on their photolysis rates,but Fe³⁺can significantly inhibit their photolysis.Same with MP and EP,alkaline conditions are more conducive to the photo-induced degradation of MDHB and EDHB.However,as a kind of dissolved organic matter,FA shows greater inhibitory effect than photosensitization in this all experiments,as a consequence,FA inhibits the decomposition of parabens and their chlorinated byproducts.Known to the function mechanism that natural photosensitizer influence on the photolysis of parabens and their chlorinated byproducts,is helpful to understand the migration and transformation of them in environmental water,furthermore,it can provide theoretical guidance for the control and disposal of the environmental pollution arising from parabens and their chlorinated byproducts.