Weeks 34-35 – Types of Exposure

When we consider chemical exposure, it’s important to think about frequency: how often will exposure occur?  Imagine you are at the gas station.  It’s a warm day, and as you fill you fill your tank with gas, you smell the faint scent of gasoline vapor in the air.  As you wrap up and put the nozzle back on the pump, a few drops of gas fall from the nozzle, thus preparing the scene for the next person.  You just experienced an acute inhalation exposure to gasoline vapor.

  • Acute: exposure to a chemical for 24 hours or less

Thankfully for you, it is a low-level exposure; you will be fine.  For the attendant who has been working at the gas station for the last few years, every time they tidy up the pumping area (take out the garbage, change out the soapy water for washing windshields, sweep up litter, and spread kitty litter to absorb larger gas spills) they are experiencing chronic exposure to inhaled gasoline vapors.

  • Chronic: exposure to a chemical for more than 3 months

When it rains, those drops of gasoline are washed down into the sewers and are carried out into Puget Sound.  Fish swimming in the area come into contact with the gasoline, absorbing it through their eyes and skin and inhaling it through their gills.  The gasoline evaporates when the weather turns sunny again, so the fish are only exposed for a few days (sub-acute exposure).

  • Sub-acute: exposure to a chemical for 1 month or less

Birds in the area feed on the gasoline-exposed fish.  It takes a few months for the birds to fully metabolize the gasoline ingested with the fish (sub-chronic exposure).

  • Sub-chronic: exposure to a chemical between 1 to 3 months

Your turn to show what you know.  Complete the Types of Exposure Google Form and then return to Weeks 34-35 – How Much Is Too Much? and continue working.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s