harmful
also
baleful
baneful
corroding
corrosive
corrupting
corruptive
counterproductive
damaging
deadly
destroying
destructive
detrimental
disadvantageous
disserviceable
distressing
hurtful
injurious
lethal
malefic
malevolent
malign
malignant
mischievous
noisome
noxious
ominous
pernicious
poisonous
prejudicial
ruining
ruinous
scatheful
see
toxic
unadvantageous
unfavorable
unprofitable
unrewarding
useless
venenate
veneniferous
venenous
addictive
adverse
beneficial
cancer-causing
carcinogenic
curative
debilitate
disruptive
hazardous
intoxicating
mephitic
soporific
undesirable
delirious
imperious
mysterious
serious