Evaluation of the Occurrence of Phthalates in Plastic Materials Used in Food Packaging

Phthalates are multifunctional synthetic chemicals found in a wide array of consumer and industrial products, mainly used to improve the mechanical properties of plastics, giving them flexibility and softness. In the European Union, phthalates are prohibited at levels greater than 0.1% by weight in most food packaging. In the current study, headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was optimized, through the multivariate optimization process, and validated to evaluate the occurrence of four common phthalates, di-iso-butyl phthalate (DIBP), butyl-benzyl phthalate (BBP), di-n-octyl phthalate (DOP), and 2,2,4,4-tetrabromodiphenyl (BDE), in different food packaging. The best extraction efficiency was achieved using the polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber at 80 °C for 30 min. The validated method showed good linearity, precision (RSD < 13%), and recoveries (90.2 to 111%). The limit of detection (LOD) and of quantification (LOQ) ranged from 0.03 to 0.08 µg/L and from 0.10 to 0.24 µg/L, respectively. On average, the phthalates concentration varied largely among the assayed food packaging. DIBP was the most predominant phthalate in terms of occurrence (71.4% of analyzed simples) and concentration (from 3.61 to 10.7 μg/L). BBP was quantified in only one sample and BDE was detected in trace amounts (<LOQ) in only two samples.

Dibutyl phthalate-mediated oxidative stress induces splenic injury in mice and the attenuating effects of vitamin E and curcumin

Dibutyl phthalate (DBP) is a ubiquitous environmental contaminant that at certain levels can be harmful to human health. Although DBP has been widely linked to immunotoxicity, any association between DBP exposure and splenic injury remains unknown. The purpose of this study was to investigate whether DBP exposure can induce splenic injury and the antagonistic effects of two antioxidants, vitamin E (VitE) and curcumin (Cur), on DBP-induced splenic injury. The levels of ROS, GSH, T-AOC, IL-1β, TNF-α, cytochrome C, caspase-8, caspase-9 and caspase-3 in the spleen homogenate of mice were measured. Any histopathological changes in the spleen were observed using H&E and toluidine blue staining. And the morphology of mitochondria was observed using Janus Green B staining. The results indicate that exposure to 50 mg/kg DBP could cause histopathological changes of the spleen and result in inflammation and apoptosis associated with oxidative stress, which may lead to splenic injury in mice. Moreover, both VitE and Cur could antagonize the oxidative stress induced by DBP to reduce splenic injury. These findings help to expand our understanding of DBP-mediated immunotoxicity, and to show that VitE and Cur can alleviate DBP-induced splenic injury and the possible DBP-associated decline in immune function.

Atopic Eczema: Genetic Associations and Potential Links to Developmental Exposures

Atopic eczema (AE), or atopic dermatitis (AD), is a common inflammatory skin disease with a disrupted epidermal barrier and an allergic immune response. AD/AE is prominently characterized by a symptomatic itch and transient skin lesions. Infants compose a significant percentage affected. Two models have been proposed to explain AD/AE skin pathology: the gut microbiome-focused inside-outside model and the outside-inside model concentrating on the disrupted skin barrier/skin microbiome. Gene disruptions contributing to epidermal structure, as well as those in immune system genes, are implicated. Over 30 genes have been linked to AD/AE with Flg and Tmem79/Matt alterations being common. Other linked disruptions are in the interleukin-1 family of cytokines/receptors and the TH2 gene family of cytokines. Inheritable epigenetic modifications of the genes or associated proteins may also be involved. Skin barrier disruption and the allergic immune response have been the main foci in mechanistic studies of AD/AE, but the role of the environment is becoming more apparent. Thus, an examination of in utero exposures could be very helpful in understanding the heterogeneity of AD/AE. Although research is limited, there is evidence that developmental exposure to environmental tobacco smoke or phthalates may impact disease. Management for AD/AE includes topical corticosteroids and calcineurin inhibitors, which safely facilitate improvements in select individuals. Disease heterogeneity warrants continued research not only into elucidating disease mechanism(s), via identification of contributing genetic alterations, but also research to understand how/when these genetic alterations occur. This may lead to the cure that those affected by AD/AE eagerly await.