BIOCHEMISTRY LABORATORY: LAB SAFETY, WASTE MANAGEMENT, AND BASIC TESTS (Notes for MLSBCHML 1st Semester)

Flashcards covering waste management hazards, hazard types, MSDS components, general lab safety, and common biochemical tests (Molisch, Benedict's, Barfoed's, Seliwanoff's) based on the provided notes.

What are the potential hazards associated with handling wastes in the lab?

Physical, chemical, biological, and ergonomic (repetitive movements/strain) hazards.

What are some hazardous healthcare waste characteristics?

May contain toxic chemicals, infectious agents, radioactive materials, sharps, cytotoxic/genotoxic drugs; may be mutagenic, teratogenic, or carcinogenic.

What does mutagenic mean?

Causes permanent changes (mutations) in DNA.

What does teratogenic mean?

Causes defects or malformations in an embryo or fetus during development.

What does carcinogenic mean?

An agent capable of causing cancer.

Name the main categories of healthcare wastes.

Non-hazardous wastes, biohazardous wastes, sharps and radioactive wastes.

What is half-life in radioactive waste?

The time required for a radioactive material to reduce its activity by half.

What is waste characterization?

Process of identifying the waste type to decide specific treatment and disposal; different wastes go into different bins/containers.

What is involved in collection and storage of wastes?

Proper labeling; trained personnel; correct containers; removal of unwanted chemicals; lab cleanout with leak response.

What is the aim of treatment and disposal in waste management?

To minimize harm to people and the environment using methods like chemical disinfection, pyrolysis, or incineration.

What is a biological hazard source?

Infectious agents (bacteria, parasites, fungi) and related diseases.

What is a sharp hazard source?

Needles, lancets, broken glass; risks include punctures, cuts, and exposure to bloodborne pathogens.

Name some chemical hazard sources.

Reagents and preservatives; can include carcinogenic or caustic agents; exposure to toxic chemicals.

What is a radioactive hazard source?

Radioisotopes and other equipment used; exposure to radiation.

What is an electric hazard source?

Frayed cords, ungrounded or wet equipment; risk of electric shock and burns.

What is a physical hazard source?

Wet floors, heavy materials; risk of falls, sprains, strains.

What is a fire hazard source?

Open flames and organic chemicals; risk of burns.

Name the key sections typically listed in a Material Safety Data Sheet (MSDS).

Physical/chemical characteristics; fire/explosion potential; reactivity; health hazards and first aid; safe handling/disposal; primary routes of entry; exposure limits and carcinogenic potential.

Why is proper labeling and container standard important in waste management?

Ensures proper identification, handling, and disposal by trained personnel.

Molisch's test: what indicates a positive result?

A violet ring at the interface.

Which sugar is non-reducing?

Sucrose.

What does green color in Benedict's test indicate?

Low concentration of reducing sugar.

Why must sulfuric acid be added carefully down the tube in Molisch's test?

To avoid splashing and to maintain a layered interface for the reaction.

Which test differentiates aldose from ketose?

Seliwanoff's test.

If a carbohydrate is positive in Molisch's and Benedict's tests but negative in Barfoed's test, what is the likely identity?

A reducing disaccharide (e.g., lactose or maltose).

If a sugar tests positive for Seliwanoff's test and Benedict's test, and is a ketose, what class does it belong to?

Ketohexose.

A diabetic patient's urine shows Benedict's positive with a yellow precipitate. What does this likely indicate?

Presence of ketose or low glucose; the notes indicate presence of ketose.

Which sugar is indicated when Molisch's, Benedict's, Barfoed's, and Seliwanoff's tests are all positive?

Fructose (a ketose monosaccharide).

After heating glassware, why should it be allowed to stand before washing?

To avoid thermal shock and possible cracking or damage.

Which is the safest heating method in the lab?

Hotplate.

In case of a large chemical spill on the floor, what should you do?

Alert others and evacuate if necessary.

What is the meaning of a buffer solution?

A solution that resists changes in pH upon addition of small amounts of acid or base.