A GC/MS Method for Determining UV Stabilizers in Polyethyleneterephthalate Bottles

Plastic Recycling Practices in Vietnam and Related Hazards for Health and the Environment

Waste plastic today is a global threat. The rapid increase in global production and use has led to increasing quantities of plastics in industrial and municipal waste streams. While in industrialized countries plastic waste is taken up by a waste management system and at least partly recycled, in low-income countries adequate infrastructure to collect and treat waste adequately is often not in place. This paper analyzes how plastic waste is handled in Vietnam, a country with a fast-growing industry and growing consumption. The recycling of plastic waste typically takes place in an informal context. To demonstrate this in more detail, two rural settlements—so-called craft villages—are taken as case studies. Technologies and processes for plastic recycling are described and related risks for human health and the environment are shown, as well as the potential for the improvement of this situation.

An overview of chemical additives present in plastics: Migration, release, fate and environmental impact during their use, disposal and recycling

Over the last 60 years plastics production has increased manifold, owing to their inexpensive, multipurpose, durable and lightweight nature. These characteristics have raised the demand for plastic materials that will continue to grow over the coming years. However, with increased plastic materials production, comes increased plastic material wastage creating a number of challenges, as well as opportunities to the waste management industry. The present overview highlights the waste management and pollution challenges, emphasising on the various chemical substances (known as "additives") contained in all plastic products for enhancing polymer properties and prolonging their life. Despite how useful these additives are in the functionality of polymer products, their potential to contaminate soil, air, water and food is widely documented in literature and described herein. These additives can potentially migrate and undesirably lead to human exposure via e.g. food contact materials, such as packaging. They can, also, be released from plastics during the various recycling and recovery processes and from the products produced from recyclates. Thus, sound recycling has to be performed in such a way as to ensure that emission of substances of high concern and contamination of recycled products is avoided, ensuring environmental and human health protection, at all times.

Evaluation of Developmental Toxicity of Ultraviolet Absorber 2-(3′,5′-Di-tert-Butyl-2′-hydroxyphenyl)-5-Chlorobenzotriazole in Rats

2-(3',5'-Di-tert-butyl-2'-hydroxyphenyl)-5-chlorobenzotriazole (DBHCB) is widely used as a UV absorber. In this study, the developmental toxicity of DBHCB was evaluated in rats. Pregnant rats were given DBHCB at 0, 62.5, 250, or 1000 mg kg(-1) day(-1) by gavage on days 5-19 of pregnancy. No deaths were observed in the pregnant rats of any group. No effect of DBHCB on the general conditions, body weight gain, or feed consumption was observed in the pregnant rats. There were no changes in the ovarian weight, gravid uterine weight, or necropsy findings in the maternal rats of the DBHCB-treated groups. No significant effects of DBHCB were found in the number of corpora lutea, implantations, live fetuses, resorptions or dead fetuses, incidence of pre- or postimplantation embryonic loss, viability of fetuses, fetal weight, or sex ratio of live fetuses. No significant difference in the incidence of fetuses with malformations or variations or degree of ossification was detected between the DBHCB-treated and control groups.

UPLC–MS as a powerful technique for screening the nonvolatile contaminants in recycled PET

The possibility of using recycled polyethylene terephthalate as a food contact material is being seriously considered, but the potential migration of nonvolatile compounds from it must be assessed to ensure that it is safe to do so. In the study presented here, four samples of recycled PET were each exposed to three food simulants under the harsh extraction conditions stipulated by European legislation regarding migration tests. The nonvolatile compounds that migrated from them were determined by ultra performance liquid chromatography-mass spectrometry using three different cone voltages, and both positive and negative ionization modes. A total of 36 chemical compounds were detected, some of which were identified, including common additives such as N,N'-di-beta-naphthyl-p-phenylenediamine (antioxidant) and 2,4-di-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl)phenol (light stabilizer) as well as degradation compounds such as ethylene terephthalate dimers and trimers. In addition, specific migration values of three common components of polyethylene terephthalate (diethylene glycol, terephthalic acid, and isophthalic acid) were determined and found to occur at levels of <1 mg/kg-much lower than the specific migration limits stipulated by European legislation.

Identification of oligomers in polyethyleneterephthalate bottles for mineral water and fruit juice

Cyclic oligomers were identified in PET bottles used for mineral water and fruit juice using MS and (1)H and (13)C NMR: a first series cyclic trimer, a first series cyclic tetramer, a first series cyclic dimmer and a second series cyclic trimer. An analytical method to determine first series cyclic trimer in these bottles was developed and validated, using HPLC. The first series cyclic trimer levels were 316-462 mg/100g of PET bottle.

Garrafas de PET para óleo comestível: avaliação da barreira à luz

Os óleos comestíveis são produtos alimentícios sensíveis à luz, pois estão sujeitos à degradação por foto-oxidação, cujas conseqüências são escurecimento do produto e alteração de aroma e sabor, levando à rejeição do produto. Assim, quando os óleos são acondicionados em embalagens transparentes, a foto-oxidação torna-se a principal causa da deterioração oxidativa devido ao efeito da luz, encurtando a vida-de-prateleira do produto e daí surgindo a necessidade da utilização de absorvedores de UV, substâncias incolores que, quando incorporadas ao material da embalagem, absorvem a energia UV incidente ou inativam cromóforos excitados protegendo o produto. Este estudo foi desenvolvido com o objetivo de avaliar a barreira à luz de embalagens de PET disponíveis no mercado brasileiro utilizadas para o acondicionamento de óleo comestível por meio da obtenção de espectros de transmissão de luz especular no UV-Visível. As embalagens que apresentaram barreira à luz foram submetidas a ensaios analíticos com a finalidade de identificação e quantificação do aditivo utilizado. Os aditivos absorvedores de UV identificados nas embalagens plásticas foram relacionados quanto à restrição de uso e limites de composição estabelecidos pela Resolução 105 da Agência Nacional de Vigilância Sanitária - ANVISA. Com isso foi possível fazer um diagnóstico do uso de absorvedores de UV em embalagens de PET utilizadas para o acondicionamento de óleo comestível disponíveis no mercado brasileiro.

Analytical methods for food-contact materials additives in olive oil simulant at sub-mg kg-1 level

Methods of analysis for four additives (two antioxidants, IRGANOX 245 and 1035; an ultraviolet absorber, CHIMMASORB 81; and an optical brightening agent, UVITEX OB) in olive oil are reported. These additives have the potential to migrate from food-contact materials into the European Union fatty food simulant olive oil, which is the most difficult matrix for analysis. The additives were chosen because they differed in their chemically active groups, had different functions within the polymer, have low proposed specific migration limits and are commonly used in food-contact materials such as polystyrenes and polyolefins. The proposed analytical methods for the additives are simple, rapid, inexpensive and also broadly applicable to the aqueous food simulants. All methods were evaluated by constructing calibration curves, measurement of recovery and precision, and determining the limits of detection. Most of the methods involve direct injection of an olive oil solution for high-performance liquid chromatography analysis with ultraviolet-visible or fluorescence detection. The methods allowed establishment of additive stability and measurement of migration of the selected additives into olive oil at different time-temperature conditions used in migration studies into food simulants.