0071643192.pdf

ENVIRONMENTAL EMERGENCIES

Cardiac Glycosides

Cardiac glycosides include:

■ Foxglove(Digitalis purpurea)

■ Common oleander(Nerium oleander)

■ Yellow oleander(Thevetia peruviana)

■ Lily of the valley(Convallaria majalis)

Foxglove contains digoxin; the others are structurally similar to digoxin.

MECHANISM OFTOXICITY

■ Inhibit the Na+-K+ATPase pump.

Digoxin toxicity is covered in detail in Toxicology (see Chapter 6).

Cyanogenic Plants

Cyanide poisoning may result after ingesting large numbers of pits/seeds of a

variety of fruits, including:

■ Peach pits

■ Apricot pits

■ Pear seeds

■ Crab apple seeds

MECHANISM OFTOXICITY

■ Amygdalin, a cyanogenic glycoside, is metabolized by the enzyme emulsin

tohydrocyanicacid.

■ Hydrocyanic acid may lead to acute cyanide toxicity.

SYMPTOMS/EXAM

■ Acute toxicity = cyanide poisoning (see Chapter 6, Toxicology)

■ Delayed symptom onset because cyanide is released by metabolism

■ Nausea/vomiting

■ Shortness of breath

■ Headache

■ Cardiovascular collapse

■ Chronic ingestion →polyneuropathies.

TREATMENT

■ GI decontamination

■ Cyanide antidote kit for acute toxicity

Nicotine-Containing Plants

TOBACCOPLANT

Tobacco plants contain the toxin nicotine. Common methods of use include

cigarette smoking, cigar smoking, pipe smoking, and smokeless tobacco (snuff).