Microplastics pollution indices of bottled water from South Eastern Nigeria

Microplastics in water, from treatment process to drinking water: analytical methods and potential health effects

“…Tap water has also been collected using the water supply cabinets established to perform other conventional analyses in drinking water or within the pipes and lines by in-line filtration of high volumes through nylon or stainless steel filters placed in different holder designs [48,52,55,68,71] . Although nets are the most described way to sample other types of surface and marine waters, the use of plankton nets is reported very few times for drinking water reservoirs [50,61] . The reason is the low amount of organic matter.…”

“…This is still hampered by the scarcity of commercially available filters of this dimension as well as the difficulty of coupling filters to the determination methods able to identify NPs. Regarding filters materials, glass microfibers (GF/C) [26,[48][49][50] , polycarbonate (PC) [46,66] , polycarbonate track-etched (PCTE) [53,62] , aluminum-coated PC [57] , cellulose [51,58,64] , polytetrafluoroethylene (PTFE) [37,60,67,70] , and stainless steel [52] have been described. As a result of the difference between the pore size of the filters used and the flow of the vacuum, findings cannot be analogized.…”

“…Strong acids also have an oxidizing effect on organic matter present in water, but the oxidant par excellence is hydrogen peroxide with or without Fe(II) to accelerate the reaction (Fenton reagent). Hydrogen peroxide can be added directly to water [43] , although it is most commonly added to the MPs after they have been separated from the sample [45,49,50,[54][55][56]61,67,70,72] . Furthermore, enzymatic proteolytic digestion has been described once [6] .…”

“…Transmission electron microscopy (TEM) has also been applied, but to a lesser extent [54] . However, the most used technique in the reviewed studies is optical microscopy, especially stereomicroscopy, due to its acceptable capacity for detecting small particles, affordability, availability, and simplicity [46][47][48][49][50][51]55,56,61,[63][64][65]70,71] . Several studies described the use of fluorescence microscopy to determine MPs, which are not fluorescent, and, therefore, it is necessary to stain them with a fluorophore, such as 1-pyrenebutyric acid N-hydroxysuccinimidyl ester (PBN) [53] , Rose Bengal [58] , or Nile red [61,62] .…”

“…Polymer chemical identification (and sometimes its quantification) is performed by using µFTIR [44,48,50,52,56,60,63,69] , µ-Raman [30,43,45,46,50,53,57,59,64,[66][67][68]70] , or Py-GC-MS [6,26,52,54,55] . However, several studies used ATR-FTIR spectroscopy [54,61,69,71] and Raman spectroscopy [63] .…”