For the final research part of the Toxin Research Project, it’s time to answer the question: how much is too much? To answer that question, you need to research how much of your toxin is in a “standard dose” of your toxin. “Standard dose” can be hard to find, and is often provided as a range. For example, a “standard dose” of caffeine might be 100-200 mg per “dose” with a dose being an 8 ounce cup of coffee or a 12 ounce can of soda. In that case, split the difference and use 150 mg as the standard dose for caffeine. Buckle up – this is often the hardest part of this project. Be persistent! If “standard dose” doesn’t work as a search term, try “amount per serving” and see if that works.

Instructions for Slide 3:

Add Slide 3 to your Google Slides deck and title it “Toxin LD_{50} Calculations”

On Slide 3, answer the following:

Click the PubChem link to your toxin from Slide 1

Locate the molecular weight (synonym for molar mass) in PubChem and enter it on Slide 3

Using the molar mass and the LD_{50} (from Slide 1), calculate the lethal dose of the toxin for humans of three different masses and show your calculation work on the slide:

10 kg

30 kg

75 kg

How many “standard doses” of the toxin does it take to reach the lethal dose for a person of mass 10 kg? 30 kg? 75 kg?

Here’s a video of my efforts to determine the “standard dose” of capsaicin per jalapeno pepper:

Need help bring these concepts together? From the video above, we learned that the average jalapeño contains 2.24 mg of capsaicin. Here is an example calculation for how many jalapeños a 75 kg person would have to eat to reach the lethal dose for capsaicin (identified in Slide 1 as 47.2 mg/kg):

75 kg x (47.2 mg capsaicin / 1 kg) x (1 jalapeños / 2.24 mg capcaisin) = 1580 jalapeños