harmfulness (n.)

• air
• badness
• balefulness
• bitchiness
• contamination
• cussedness
• deadliness
• devilment
• devilry
• deviltry
• hatefulness
• injuriousness
• insalubriousness
• insalubrity
• lethality
• maleficence
• malice
• maliciousness
• malignance
• malignancy
• malignity
• meanness
• mischievousness
• nastiness
• noisomeness
• noxiousness
• ominousness
• orneriness
• perniciousness
• pollution
• toxicity
• unhealthfulness
• unhealthiness
• unwholesomeness
• viciousness
• virulence
• water
• wickedness