mole_concentration_of_particulate_organic_mercury_in_sea_water mol m-3 [MLM3] "Mole concentration" means number of moles per unit volume, also called "molarity", and is used in the construction "mole_concentration_of_X_in_Y", where X is a material constituent of Y. A chemical species or biological group denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". Particulate means suspended solids of all sizes. "Organic mercury" describes a family of chemical species in which mercury atoms covalently bonded to carbon-containing groups, forming organomercury compounds (e.g., methylmercury (MeHg), monomethylmercury (MMHg), dimethylmercury (DMHg), ethylmercury (EtHg)).