Editing Polychlorinated biphenyl (section)

===Water===
Because of their low [[vapour pressure]], PCBs accumulate primarily in the [[hydrosphere]], despite their [[hydrophobicity]], in the organic fraction of [[soil]], and in [[organism]]s including the human body.<ref>{{cite journal | vauthors = Norström K, Czub G, McLachlan MS, Hu D, Thorne PS, Hornbuckle KC |display-authors=3| title = External exposure and bioaccumulation of PCBs in humans living in a contaminated urban environment | journal = Environment International | volume = 36 | issue = 8 | pages = 855–861 | date = November 2010 | pmid = 19394084 | pmc = 2891214 | doi = 10.1016/j.envint.2009.03.005 | bibcode = 2010EnInt..36..855N }}</ref> The hydrosphere is the main reservoir. The immense volume of water in the oceans is still capable of dissolving a significant quantity of PCBs.<ref>{{cite web |title=A Look at How Long-Banned PCBs Persist in the Ocean |url=https://eos.org/research-spotlights/a-look-at-how-long-banned-pcbs-persist-in-the-ocean |website=Eos|date=7 May 2019 }}</ref>

As the pressure of ocean water increases with depth, PCBs become heavier than water and sink to the deepest ocean trenches where they are concentrated.<ref>{{cite news|url=https://www.economist.com/science-and-technology/2017/02/18/nasty-chemicals-abound-in-what-was-thought-an-untouched-environment|title=Nasty chemicals abound in what was thought an untouched environment|newspaper=The Economist|access-date=10 April 2022|date=18 February 2017}}</ref>