Modifiers matching buffer:

• inexpensive,
• volatile,
• physiological,
• urinary,
• nonvolatile,
• minor,
• alkaline,
• working,
• organic,
• gaseous,
• appropriate,
• aromatic,
• inorganic,
• mobile,
• common,
• salt,
• natural,
• dilute,
• cellular,
• active,
• biological,
• basic,
• enzymatic,
• charged,
• nontoxic,
• complex,
• exogenous,
• chemical,
• simple,
• acidic,
• endogenous,
• stable,
• intracellular,
• standard,
• acid,
• ancillary,

Simple categories matching nontoxic:

• metal,
• material,
• fabric,
• antifreeze,
• acid,
• ingredient,
• agent,
• chemical,
• liquid,
• fluid,
• solvent,
• buffer,
• gas,
• leaf,
• substance,
• component,
• plant,
• constituent,
• solute,
• solution,
• salt,
• product,
• bark,
• oil,
• coating,
• solid,
• compound,