Deck 17: The Lung and Gill Exposures Representing Toxic Concentrationsmodel for Environmental Toxicology

Question 1

What chemical formed by electrical discharges causes oxidant damage to the respiratory tract starting with the nasal epithelium?

Answer 1

Ozone is that chemical and is found following electrical storms or high traffic with cars. It has been studied extensively as a model respiratory toxicant.

Question 2

Cancers of the larynx are fairly rare for most cigarette users, but marijuana smokers contract this disease. Why?

Answer 2

It has to do with particle size from unfiltered burn products. Metabolism of those products can activate them to DNA-reactive carcinogens.

Question 3

Why will vaping (nicotine electronically put into a vapor) increase the person's response to other air pollutants similarly to a standard smoker of cigarettes?

Answer 3

Although vaping will not necessarily get burn products, the nicotine itself will paralyze the cilia in the trachea/bronchioles and not remove air pollution particles as well (longer residence time). Nicotine will also be metabolized in the lung to known carcinogenic metabolites (Type II and Clara cells of the alveoli biotransform nicotine-derived smoke products 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonornicotine
(NNN) via α-hydroxylation pathways to reactive intermediates that form DNA adducts and subsequently lung cancer).

Question 4

Why do metals that cause gill damage not only affect respiratory functions but also functions that appear in the mammal to be controlled by the kidney?