Modifiers matching impurity:

• airborne,
• harmful,
• stubborn,
• physical,
• inorganic,
• volatile,
• particulate,
• microscopic,
• active,
• random,
• foreign,
• coarse,
• solid,
• dilute,
• suspended,
• separate,
• residual,
• damaging,
• smaller,
• sticky,
• reactive,
• atmospheric,
• organic,
• minute,
• insoluble,
• colloidal,
• minor,
• common,
• environmental,
• micro,
• unwanted,
• harmless,
• small,
• nonpolar,
• dissolved,
• soluble,
• heterogeneous,
• undesired,
• desirable,
• natural,
• chemical,
• biological,
• mechanical,
• fluid,
• light,
• heavier,
• polar,
• hazardous,
• homogeneous,
• lightweight,
• interfering,
• little,
• off,
• visible,
• ionic,
• unavoidable,
• ordinary,
• initial,
• anionic,
• up,
• out,
• absorptive,
• mental,
• possible,
• lighter,
• mobile,
• corrosive,
• gaseous,
• fine,

Simple categories matching ionic:

• contaminant,
• equilibrium,
• crystal,
• oxalate,
• compound,
• substrate,
• liquid,
• metabolite,
• component,
• gas,
• solid,
• group,
• fluid,
• metal,
• salt,
• drug,
• molecule,
• ligand,
• fluoride,
• nitrate,
• substance,
• chemical,
• current,
• system,
• material,
• azide,
• surfactant,
• particle,
• mineral,
• oxide,
• solute,
• conductor,
• tool,
• polymer,
• constituent,
• signal,
• waste,
• solution,
• insulator,
• use,
• atom,
• impurity,
• substitution,