Organic Solvents

Question 1

what are the main classes of solvents?

Answer 1

aromatic hydrocarbs
aliphatic hydrocarbons
chlorinated aliphatic hydrocarbons
alcohols
glycols

Question 2

general effects of OSs?

Answer 2

CNS depression or narcosis; nonspec tox related to altering membrane fluidity;
interactions with other toxicants and drugs; e.g., due to induction of CYP enzymes
solvents are INDUCERS

Question 3

how do OSs target the liver, and egs?

Answer 3

general effects: cirrhosis, steatosis,necrosis, cancer
eg. ethanol– steatosis, cirrhosis, cancer promoter
CCl4–>CYP-catalyzed reduction rxn to CCl3e; leads to lipid perox, necrosis, and cancer

Question 4

how do OSs target the kidney, and eg

Answer 4

e.g. ethylene glycol; forms calcium oxalate, which ppts in kidney tubs

Question 5

how do OSs target NS?

Answer 5

causze peripheral neuropathy–damage to nerves at periphery, esp hands and feet
maybe causes chronic fatigue syndrome

Question 6

how do OSs target the eye, and egs?

Answer 6

methanol–metabolized to formaldehyde by alcohol dehydrogenase
formaldehyde metabolized to formic acid by aldehyde dehydrogenase
formic acid accumulates in eye (target organ)–causes eye toxicity–>blindness
treatment: ethanol, competes with MetOH for ADH

Question 7

how do OSs target the hematopoetic system, and egs?

Answer 7

benzene–causes extensive bone marrow tox; forms quinone in bone marrow, producing ox stress
toxicokinetic mech of action: 1. bone marrow has high activity of myeloperoxidase, produces semiquinone and quinone
2. bone marrow has LOW activity of NADPH-quinone oxidoreductase