Please look at the following below links which may help you in your analysis.

Thanks

Thank you! It helps a lot!

Metallurgy

Dear Jonathan J. Richter many thanks for your interesting technical question. Once you have organic selenium and tellurium compounds, their evil smell will easily tell you when small amounts of them are around in the laboratory. For entitled more general overview on the role of tellurium in the environment, please see this very useful review article entitled

Tellurium in the environment: A critical review focused on natural waters, soils, sediments and airborne particles

Article Tellurium in the environment: A critical review focused on n...

This article is freely available as public full text on ResearchGate. As a review article it also lists a number of potentially useful original references.

For selenium, please have a look at this article which is perhaps somewhat outdated (published 1981):

Determination of Selenium in the Environment and in Biological Material

https://ehp.niehs.nih.gov/doi/pdf/10.1289/ehp.8137183

This paper can be freely downloaded as full text from the general internet.

The third articles deals with both elements. It is entitled

Determination of tellurium and selenium in atmospheric aerosol samples by graphite furnace atomic absorption spectrometry

Article Determination of tellurium and selenium in atmospheric aeros...

Thank you! I'll look at them ASAP