Figure 5. — The effect of environmental factors, such as temperature and salinity, on the accumula- 

 tion of radioactivity by invertebrates is studied under controlled conditions in the laboratory. In- 

 vestigators remove organisms from the experimental environment, analyze the live organisms for 

 radioactivity content, then return them to the aquaria. The effect of temperature and salinity on 

 the accumulation of the radioactivity by the organisms is evaluated by statistical analysis of the 

 data. 



Figure 6. — Radioactivity content of organisms used in laboratory experiments is measured with 

 specially designed electronic equipment containing a scintillation detector. Here the investigator 

 is placing a plastic container holding one oyster into a chamber where the amount of radioactive 

 zinc accumulated by the oyster can be measured. 



