analysis
analyzing
bacteria
biotechnology
bottle
bright
chemical
chemist
chemistry
clean
contaminated
contamination
control
drink
ecology
ecosystem
environment
exam
examining
exclamation
experiment
fresh
idea
infection
lab
laboratory
liquid
man
medical
medicine
microbes
microbiology
pollutant
pollution
quality
research
researcher
safety
sample
science
scientific
scientist
student
studying
test
testing
toxic
tube
virus
water