Posts: 2
Joined: Fri Mar 15, 2019 10:24 am
Occupation: Student

LC50 help

Postby nanosilvergirl » Fri Mar 15, 2019 10:29 am

Hi, I'm doing the project on the effects of nanosilver on Daphnia Magna. I want to do the LC50, however I don't know a good program to do it on. Google Sheets seems to not be a good method. All of my Daphnia died in 4 hours, and I recorded the dead and alive Daphnia every hour, so I will be doing 4 different LC50 concentrations, correct? Does this mean I take the average of all to find the LC50 number for the nanosilver?

As well, do I do the dose-reponse curve for each time point as well? Do I find the LC50 from the dose-reponse curve? I researched on how to fin the LC50 and lots of them require logs which is very confusing to me.


Moderator Note: I combined your questions into one post so experts will see that your questions have not yet been answered.
Last edited by MadelineB on Fri Mar 15, 2019 7:20 pm, edited 1 time in total.

Posts: 622
Joined: Fri Jun 20, 2014 4:42 pm
Occupation: Biostatistician/Data Scientist

Re: LC50 help

Postby MadelineB » Sun Mar 17, 2019 2:46 pm

Hello Nanosilvergirl and welcome to Science Buddies,

Are you doing this Science Buddies project? ... -pond-life

There is a good reference in the Background section of this project which should help you understand about using bioassyas to calculate the LC50. Try working through the examples: ... alyze.html

Let us know if this helps!

Return to “Grades 9-12: Life, Earth, and Social Sciences”