Potential risk of BPA and phthalates in commercial water bottles: a minireview

The sample preparation has been considered as the Achilles’ heel (Fumes et al. 2015). Matrix-related compounds can be co-extracted and can interfere in the analysis; so, the sample preparation has a multifarious role related to target analyte extraction, preconcentration and clean-up from co-existing species (Gao et al. 2015). A preconcentration step is usually necessary before the final analysis of compounds (Gao et al. 2015; Feizi et al. 2017). However, some methods often require high amounts of organic solvents that are harmful to the environment (Gao et al. 2015; Feizi et al. 2017; Płotka-Wasylka et al. 2017). A concept that has been approached is the green analytical chemistry, which decreases or eliminates organic solvents during the extraction procedure (Fumes et al. 2015; Płotka-Wasylka et al. 2017). Karayaka et al. (2019) developed a method to extract BPA from drinking water bottles using a switchable polarity solvent (N,N-dimethylbenzylamine), which is a green solvent. Also, it is very important to use a proper sample preparation to reach the required lower LODs (Gao et al. 2015). Discoveries in materials science may supply new tools for the preparation of samples (Jalili et al. 2020). Mohammadnezhad et al. (2017) developed ionic liquid-bonded fused silica as a new solid-phase microextraction (SPME) fiber for the liquid chromatographic determination of BPA in mineral water bottled in PET. Wei et al. (2018) synthesized a novel magnetic solid-phase extraction (MSPE) for the determination of six phthalic acid esters in mineral water (including BBP, DBP and DEHP). The development of natural sorbents has also been investigated, which are cheap and readily available and sometimes their performance was comparable with synthetic sorbents (Sajid et al. 2016).

Some works in Table 1 developed extraction methods. González-Sálamo et al. (2017) used the first application of core–shell poly (dopamine) magnetic nanoparticles as a sorbent for the extraction of a group of 11 phthalic acid esters of interest. Pinsrithong & Bunkoed (2018) synthesized a hierarchically porous composite nanostructure of polypyrrole, reduced graphene oxide, magnetite nanoparticles and alginate hydrogel microspheres (PPy-rGOx-Fe3O4). They applied as a magnetic solid-phase extraction adsorbent for PAEs, including BBP, DBP and DEHP. Farajzadeh et al. (2019) developed a natural and costless adsorbent for the accomplishment of a dispersive solid-phase extraction (DSPE) procedure followed by dispersive liquid–liquid microextraction (DLLME) for the extraction and preconcentration of PAEs and alkylphenols. None of the methods of Table 1 present LOD and LOQ values lower than the MCL to BPA in drinking water by EC (0.1 μg/L), but are lower than in China (10 μg/L) (EC 2020; GB-5749-2006).

Currently, MCL has not been established for BBP (US EPA 2019a), although, in 1990, US EPA proposed an MCL of 100 μg/L (Parks et al. 1993). In 2004, New Jersey State Primary and Secondary Drinking Water Standards derived the same value, multiplying the drinking water equivalent level of 7 mg/L by the relative source contribution factor of 20% and dividing the result by the additional uncertainty factor of 10 for possible human carcinogens (NJDEP 2004). All methods show LOD and LOQ below this proposed MCL value for BBP.

Almost all methods exhibit LOD and LOQ lower than DBP by China for drinking water (3 μg/L) (GB-5749-2006). All methods show LOD and LOQ lower than DEHP by US FDA for bottled water (6 μg/L) and by WHO, Codex Alimentarius, China for drinking water (8 μg/L) (Codex Alimentarius 2001; GB-5749-2006; WHO 2017; ECFR 2020). Yang et al. (2017) analyzed BBP, DBP and DEHP by GC–MS/LLE. The values of LOD and LOQ are given in mg/kg. The LOD and LOQ are lower than the SML values by the EU for BBP (30 mg/kg), DBP (0.3 mg/kg) and DEHP (1.5 mg/kg) (EFSA 2019).