poisonous (adj.)

• bad
• baleful
• baneful
• brackish
• catching
• cloying
• communicable
• contagious
• corrosive
• corrupting
• corruptive
• counterproductive
• damaging
• dangerous
• deadly
• defamatory
• deleterious
• destructive
• detrimental
• diabolical
• disadvantageous
• distressing
• evil
• fatal
• fetid
• foul
• fulsome
• harmful
• high
• hurtful
• icky
• infectious
• infective
• injurious
• lethal
• maggoty
• malefic
• malevolent
• malicious
• malign
• malignant
• mawkish
• mephitic
• miasmal
• miasmic
• mischievous
• mortal
• nasty
• nauseating
• nauseous
• noisome
• noxious
• offensive
• ominous
• overripe
• pernicious
• pestiferous
• pestilent
• pestilential
• prejudicial
• rancid
• rank
• rebarbative
• rotten
• septic
• sickening
• slanderous
• spoiled
• stinking
• toxic
• toxicant
• venomous
• vicious
• vile
• virulent
• yucky