D6 Environmental impact of some medication Flashcards
What are the three types of waste produced by medicinal chemistry?
- Solvent waste
- Antibiotic waste
- Nuclear waste
How is solvent waste generated?
When synthesising and extracting complex molecules to form drugs, organic solvents are used. Left-overs from this are often toxic which causes problems when disposing them.
How is solvent waste disposed?
It is disposed by incineration which releases the toxins into the environment
What are the three factors that assess the sustainability of solvents?
- toxicity to workers
- safety of the process
- harm to the environment
this bases the criteria to determine desirable and undesirable solvents
How are solvents classified? Give examples
Preferred solvents (water, alcohols, esters)
* water H20
* ethanol C2H5OH
* 2-propanol CH3CH(OH)CH3
* propanone CH3COCH3
* ethyl ethanoate CH3COOC2H5
Undesirable solvents (chlorinated and aromatic compounds, ethers)
* dichloromethane CH2Cl2
* methanol HCHO
* tetrachloromethane CCl4
* diethyl ether C2H5OC2H5
* benzene C6H6
What is the safest solvent for the environment?
water H2O
What is nuclear waste?
Radioactive waste that is hazardous to living things and the environment
How is nuclear waste disposed?
(+) give examples of each type of nuclear waste
It depend on the level of waste and the amount of time that it remains radioactive. Whether it gives of large or small amounts of ionizing radiation for a long or short period of time
Low-level waste (short half-life)
* The contaminated material is sealed in a contained for a few hours or days until the radioactivity has decreased. It is then disposed by conventional means
* Stored in shielded containers until the isotopes have decayed and then disposed of as non-radioactive waste.
* Gowns, protective clothing, shoe covers, tissues, needles, mops
High-level waste (long half-life)
* the waste is stored underwater in reinforced cooling ponds from 5 to 10 years. It is then transferred to a dry storafe in heavily sealed structured burried underground
* Radioactive sources (Co-60, Cs-137)
Co-60, Cs-137 are elements in the periodic table
Nuclear medicine mostly produces low-level waste
in what ways are antibiotics released into the environment?
- the use of antibiotics in animal feeds (animal waste - soil - water - human food chain)
- improper disposal of antibiotic medicines by hospitals and households.
- antibiotics excreted by humans in urine. enter the sewage system at low concentrations
- Sewage treatment plants are rarely equipped to remove antibiotics from wastewater, therefore they can ultimately end up in the drinking water supply.
why is the release of antibiotics into the environment bad?
Because they inrease the exposure of bacteria to the antibiotics, making them more likely to mutate to being resistant.
Strict measures of infection control and antibiotic use should be a global priority. How can individuals help?
These efforts must be backed to minimize the release of antibiotics into the environment. Individuals can contribute by avoiding overuse and complying with instructions to complete a dose only when required
What is Tamiflu? What does it do?
Tamiflu (oseltamivir) is an antiviral that lessens the spread of a virus in the body by preventing the release of new viral particels from their host cells.
What are the 12 principle of Green Chemistry?
- Prevent waste
- Maximize atom economy
- Design less hazardous chemical syntheses
- Design safer chemicals and products
- Use safer solvents and reaction conditions
- Increase energy efficiency
- Use renewable feedstocks
- Avoid chemical derivatives
- Use catalysts, not stoichiometric reagents
- Design chemicals and products to degrade after use
- Analyze in real time to prevent pollution
- Minimize the potential for accidents
Revise: Atom economy
Where is oseltamivir (tamiflu) found? Why is the extraction of this compound difficult? What alterantives exist to obtain it?
- It is found in low concentration in many plants (needles of pine trees and chinese star anise (star-shaped fruit)
- the extraction is a lengthy chemical procedure
- producing it through fermentation reactions of genetically engineered bacteria
