agent
alert
area
attention
bacteria
bacterial
beware
bio
biohazard
biologic
biological
biology
black
caution
chemical
chemicals
contagious
contamination
danger
dangerous
environment
epidemic
forbidden
hazard
hazardous
icon
illustration
isolated
lab
laboratory
medical
poison
protect
protection
restricted
risk
safety
science
security
sign
signal
substance
symbol
toxic
vector
virus
warn
waste
weapon
yellow