In vitro cytotoxic effects of secondary metabolites of DEHP and its alternative plasticizers DINCH and DINP on a L929 cell line

Abstract

Background: Phthalic acid esters are widely used to improve the plasticity of PVC in medical devices (MD). The most famous plasticizer is DEHP, whose use in medical devices has been contested by the European authorities since 2008. Several alternative plasticizers are being considered to replace DEHP, such as DEHT, TOTM, DINP or DINCH, but they are also released from the PVC throughout their life cycle and are metabolized in the same way as DEHP. Objectives: Our study focuses on the in vitro cytotoxicity of two alternative plasticizers (DINCH and DINP) contained in certain medical devices. They are likely to migrate and be transformed in vivo into the primary and secondary metabolites by a metabolism similar to that of DEHP. This preliminary study is the first to assess the in vitro cytotoxicity of oxidized metabolites of DINCH and DINP based on the EN ISO 10-993-5 standards documents. Methods: We have studied the complete multi-step organic synthesis of secondary metabolites of DINP and DINCH and have performed cytotoxicity tests on L929 murine cells according to the ISO-EN ISO 10993-5 standard design for the biocompatibility of a MD. The tested concentrations of obtained metabolites (0.01, 0.05 and 0.1 mg/mL) covered the range likely to be found for DEHP (total metabolism) in biological fluids coming into direct contact Highlights  7-oxo-MMeOCH and 5-oxo-MEHP induced no action on cell proliferation at 0.1 mg/mL  Among secondary metabolites of DEHP, 5-oxo-MEHP induced an action on L929  Among secondary metabolites of MMeOCH, 7-oxo-MMeOCH induced an action on L929  Secondary metabolites of MMeOCH are less toxic than MMeOCH  Secondary metabolites of MMeOP are not toxic like MMeOCH

Urinary Concentrations of Major Phthalate and Alternative Plasticizer Metabolites in Children of Thailand, Indonesia, and Saudi Arabia, and Associated Risks

“…19,20 Such observations are of public health importance, because first experimental evidence suggests the toxic potential of some of these alternatives, although their associations with toxicological consequences in general human populations are not well understood yet. 21,22 Children tend to exhibit higher intake amounts of phthalates than adults, because of their greater surface area to body weight ratio, 23 intake amount relative to body weight, 24 and likelihood of distinct behaviors (such as mouthing) that would increase exposure. 25 Phthalate exposures among children are, however, most extensively investigated for certain geographical regions such as North America, Europe, and East Asia.…”

Di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH) alters transcriptional profiles, lipid metabolism and behavior in zebrafish larvae

“…Several in vivo and in vitro toxicological studies have analyzed possible adverse effects of DINCH and contradictory results were obtained ( Campioli et al., 2015 ; Campioli et al., 2019 ; Campioli et al., 2017 ; David et al., 2015 ; EFSA, 2007 ; Eljezi et al., 2019 ; Engel et al., 2018 ; Nardelli et al., 2017 ; Vasconcelos et al., 2019 ). The in vivo toxicological studies of DINCH on rats have shown no effect on behavior, organ weight, serum chemistry ( David et al., 2015 ), and no evidence of reproductive toxicity or endocrine disruptive properties ( EFSA, 2007 ).…”

Ex Vivo Model to Assess the Exposure of Patients to Plasticizers from Medical Devices during Pre-CAR-T Cells’ Apheresis

“…In addition, DEHP has also been categorized as carcinogenic, mutagenic, or toxic for reproduction 1B under the Classification Labeling and Packaging (CLP) Regulation (Testai et al, 2016; Regulation (EU) 2017/745 [27]), due to suspected reprotoxicity in humans [10]. Moreover, DEHP-and especially its primary metabolite MEHP (mono(2-ethylhexyl)phthalate)-is also responsible for a significant decrease in cell viability as soon as reaching blood concentrations of 0.05 mg/mL and 0.01 mg/mL, respectively [28]. Our model (simulant) does not allow us to measure the exposure to MEHP, due to the absence of the esterase contained in the bloodstream (therefore, no metabolism can occur).…”