As part of another chat, someone mentioned alkaloids in Lungwort (Pulmonaria officinalis). I'm thinking they mean pyrrolizidine alkaloids (PAs) as its Boraginaceae. However, I came across a research paper a couple of years ago saying that they had found no PAs in Lungwort. Previous to that, I'm sure i had read in a book somewhere the same caution and so I had meant to follow it up but never got round to it.

So, now that I've been reminded - a quick google-scholar and a look out of my old notes shows the following. Any thoughts?

Pyrrolizidine alkaloids in medicinal plants of Boraginaceal: Borago officinalis L. and Pulmonaria officinalis L. Lüthy J, Brauchli J, Zweifel U, Schmid P, Schlatter C. Pharm Acta Helv. 1984;59(9-10):242-6.
http://www.ncbi.nlm.nih.gov/pubmed/6483923
Its in German but the abstract says "No PAs could be detected in several samples of the drug Pulmonaria officinalis L."

Selective Sequestration of Pyrrolizidine Alkaloids from Diverse Host Plants by Longitarsus Flea Beetles S. Dobler, W. Haberer, L. Witte and T. Hartmann
http://www.springerlink.com/content/k09h562218235436/
"In one host plant, Pulmonaria officinalis, no PAs could be detected in the leaves, yet were present in the beetles collected from them. We suggest this is due to uptake of PAs during the root-feeding larval stage."

Interesting! but then this:

Alkaloids - secrets of life: alkaloid chemistry, biological significance ... By Tadeusz Aniszewski
says that typical Boraginaceae PAs have been found in all parts of Pulmonaria officinalis and P. obscura "This means that P. off is not an exception in not having PAs" (paraphrased)
However, they cite the following as evidence:

Planta Med 2002; 68(5): 480-482
Pyrrolizidine Alkaloids in Pulmonaria obscura

W. Haberer1, L. Witte2, Th. Hartmann2, S. Dobler1
https://www.thieme-connect.com/ejournals/abstract/plantamedica/doi/10.1055/s-2002-32088
"Leaves, roots and rhizomes, and inflorescenses of Pulmonaria obscura from two localities and of two different growth forms within one site were analyzed by GC-MS for their content in pyrrolizidine alkaloids (PAs). In roots and rhizomes PAs of the lycopsamine type typical for the Boraginaceae could be detected, e. g. intermedine, lycopsamine, and their O7-derivatives. The total PA concentrations in roots and rhizomes lay between 0.026 and 0.158 mg/g dry weight. In leaves and inflorescenses, on the other hand, only trace amounts of PAs (below 0.4 ng/mg dry weight) could be detected. No significant differences in total concentration of PAs could be found between the two sites."

No P. officinalis tested and only trace PAs in leaf of P. obscura...

I have read alot of differing literature on PA's and myself have come to the concultion that in acute cases I use high doses of certain herbs containing PA's

I always give milk thistle along side this prescription that is short -2 weeks maximun.

And for chronic stuff I use drop doses of herbs so not enough for PA's to poison.

I hardly ever prescribe comfrey internally I but borage is a staple

With all the research into herbs containing it or not I think it will also depend on where and under what conditions they are grown -but I think many herbs containing the PA's will have other constituents that buffer them perhaps...

K