Simple categories matching unnatural:

• color,
• variation,
• compound,
• component,
• cause,
• death,
• action,
• substance,
• event,
• food,
• stimulant,
• disturbance,
• drink,
• drug,
• chemical,
• object,
• condition,
• substrate,
• catastrophe,
• shade,
• force,
• surface,
• danger,

Members with property unnatural:

• insect,
• freon,
• pesticide,
• cocaine,
• logging,
• contaminant_storage,
• pink,
• hormone,
• confinement,
• suicide,
• green,
• shooting,
• soya_meal,
• plastic,
• neon_green,
• nuclear_meltdown,
• sweet_potato,
• urban_encroachment,
• beach_lighting,
• fire,
• herbicide,
• flow,
• icecream,
• pumpkin,
• parricide,
• steroid,
• reaction,
• chocolate,
• orange,
• vehicle_impact,
• purple,
• chlorofluorocarbon,
• styrene,
• riot,
• tile_floor,
• lolly,
• lightning,
• injection_needle,
• violent_death,
• cheese,
• swimming,
• illness,
• mirror,
• roads,
• road_building,
• radiation,
• computer_failure,
• fatty_acid,
• rhythmic_loop,
• fire_suppression,
• bolster,
• antibiotic,
• dog_attack,
• dwarf_habit,
• explosion,
• stress,
• bark,
• yellow,
• rot,
• steel,
• soil,
• strife,
• chemical_toxin,
• ph_buffer,
• trauma,
• primary_red,
• drug_use,
• starches,
• light_blue,
• nylon,
• bread,
• chlorobenzene,
• bright_red,
• pavement,
• sugar,
• plastic_container,
• beer,
• alcohol,
• sock,
• scouring,
• fright,
• candy_wrapper,
• vegetable,
• pop,
• captivity,
• depression,
• poison,
• interracial_marriage,
• tide,
• refined_sugar,
• glass,
• pull,
• cows_milk,
• neon_pink,
• delusion,
• chemical,
• vacuum,
• hydrocarbon,
• soil_disturbance,
• watch,
• thunder,
• concrete,
• pet-food,
• river_flow,
• bean,
• blue,
• injury,
• medication,
• driveway,
• sedimentation,
• viral_protein,
• anabolic_steroid,
• drug,
• car_crash,
• disaster,
• bottle,
• sand,
• high_wind,
• popcorn,
• sea_shell,
• pastry,
• ddt,
• crack,
• inadequate_diet,
• visual_hallucination,
• ball,
• war,
• aircraft_collision,
• aqua,
• flood,
• carrot_orange,
• fake_food,
• soft_drink,
• infanticide,
• plastic_ship,
• grass,
• fried_snack,
• chalk,
• celestial_interference,
• bologna,
• cigarette,
• accidental_death,
• frost,
• terror_attack,
• bruise,
• heavy_metal,
• trapping,
• white_bread,
• sidewalk,
• dirt,
• cigarette_smoke,
• cage,
• refined_flour,
• acid,
• soda,
• cereal,
• cords,
• grain,
• compact_soil,
• possession,
• legume,
• excess,
• automobile,
• dog,
• push,