Modifiers matching impurity:

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

Simple categories matching harmful:

• chemical,
• drug,
• diuretic,
• substance,
• problem,
• organism,
• sweetener,
• deeds,
• abnormality,
• stain,
• content,
• metal,
• fish,
• material,
• force,
• contaminant,
• radiation,
• fumes,
• microorganism,
• change,
• emotion,
• symptom,
• antigen,
• product,
• practice,
• cell,
• bacteria,
• compound,
• code,
• group,
• industry,
• residue,
• experience,
• solute,
• test,
• invertebrate,
• object,
• program,
• occurrence,
• molecule,
• occupation,
• adulterant,
• stimulus,
• addiction,
• aggression,
• event,
• sediment,
• halogen,
• intermediate,
• tool,
• exposure,
• weeds,
• choice,
• power,
• conduct,
• monomer,
• element,
• impurity,
• sector,
• residual,
• pathology,
• frequency,
• effect,
• salt,
• utterance,
• microbe,
• volatile,
• curio,
• procedure,
• ion,
• service,
• state,
• virus,
• place,
• condition,
• cause,
• particle,
• emission,
• energy,
• idea,
• elements,
• constituent,
• fluid,
• danger,
• creature,
• atmosphere,
• food,
• treatment,
• radical,
• parasite,
• quality,
• pesticide,
• email,
• crime,
• preservative,
• thing,
• pollutant,
• gas,
• subsidy,
• fat,
• behaviour,
• influence,
• information,
• component,
• inhalant,
• behavior,
• tax,
• allergen,
• result,
• software,
• plant,
• fumigant,
• yeast,
• circumstances,
• alkaloid,
• weather,
• intruder,
• flavoring,
• deposit,
• consequence,
• filler,
• contamination,
• reactant,
• disease,
• light,
• gene,
• drinking,
• stuff,
• nutrient,
• environment,
• disorder,
• liquid,
• sport,
• animal,
• act,
• aerosol,
• medication,
• notion,
• commodity,
• stress,
• therapy,
• fuel,
• item,
• habit,
• entity,
• germ,
• illness,
• mineral,
• toxin,
• predator,
• pathogen,
• oxidant,
• fiber,
• phenomenon,
• work,
• ingredient,
• trait,
• action,
• activity,
• matter,
• arachnid,
• complication,
• bug,
• situation,
• agent,
• fauna,
• stimulant,
• pest,
• irradiation,
• intervention,
• herb,
• insect,
• infection,
• article,
• property,
• caterpillar,
• fraction,
• waste,
• defect,
• beverage,
• factor,
• solvent,
• process,