Emerging Chemicals of Concern Flashcards
Pharmaceuticals
- Need to be biological active
- Characters of xenobiotics
- Can pass across membrane - lipophilic
- Persistence to have effect
- Can bioaccumulate
Where does environmental exposure to pharmaceutical come from?
Municipal waste water, agricultural runoff
What are the three possible fates for the pharmaceuticals?
- Biodegrades
- Remains sludge - compounds that are highly lipophilic do not readily degrade
- End up in receiving waters - hydophilic but still persistent
Antibiotic axytetracycline
Fish feed additive
- used against bacterial disease
- binds to 30S subunit interfering with tRNA/mRMA complex
- Remains for up to 12 weeks after administration
Endocrine system
Responsible for releasing hormones (chemical messengers)
- act on other cells within body
- interact with cell receptors (plasma membrane or nuclear)
- triggers biological response within the target cell
Diethylstilbestrol (DES)
Synthetic estrogen given to pregnant women
- increased vaginal or cervical cancer
- exposed in utero (DES daughters), have increase infertility, ectopic pregnancy, miscarriage, pre-term labour
Epigenetics
Study of mitotically and/or meiotically heritable changes in gene function that cannot be explained by change in DNA sequences
Agonist
Synthetic chemical mimics natural hormone and binds to receptor causing a similar to response by the cell
Antagonistic
Synthetic chemical mimics natural hormone and minds to a receptor and prevents a normal response
Synthetic estrogen and fish
Male fish leaving near municipal sewage outlets - female and female sex characteristics
- livers produce vitellogenin (Vg) egg yolk protein
- low level of natural and synthetic estrogen
Oxybenzone
Found in sunscreen
- affects coral planulae, may lead to coral bleaching
- reduction in ciliary movement and morphology
