[PhilGeis]

As Perry said, look to those professional entities like CIR and SCCS who detail information and live with their decision.  You can alsways find a researcher publishing an affimative opinion of disaster based usually on irrelevant and or bad science.   

On the credibility side - SCCS just published this opinion of Propyl parabens.  Please note the depth of its consideration.   ” SCCS has concluded that propylparaben is safe when used as a preservative in cosmetic products up to a maximum concentration of 0.14 %.” https://ec.europa.eu/health/sites/health/files/scientific_committees/consumer_safety/docs/sccs_o_243.pdf?fbclid=IwAR0p-PkyKeHFEcUyorfxdteQXrJru35M_f5GhXgAO2iy096yIVavgmggcVo

[PhilGeis]

Paprik said:

I’m really struggling with getting a nice preservative. 
I’ve started with Liquid Germall Plus, but I’m afraid some of my customers won’t and don’t like the fact, that it’s formaldehyde donor. 
So was looking for something different. I found Euxyl PE 9010. I like it, but the smell is just nah. A new one I tried was Geogard Ultra TM (Gluconolactone (and) Sodium Benzoate (and) Calcium Gluconate), it’s a powder, seems to be super nice and easy to use, but it messes up with my pH. So I tried Microcare DB, seems also nice, it’s EcoCert, BUT the smell! So it’s hard to find one without any smell, “scary” names like Parabens or Formaldehyde and won’t mess up with my products. 

But as for me, I’m using Liquid Germall Plus the most. 
Also thinking about Naticide - but I know there’s a smell to it. And it’s expensive. 

What do you think about Potassium Sorbate & Sodium Benzoate? 

Certainly a wide range of anticipated levels of efficacy in your suggestions - mostly on the poor side.   Not knowing the product category -I’ll offer that you should assemble a combination of  preservatives (with a chelator like EDTA)  that SHOULD work and confirm with PET.  None of the sytems you desceibed are likely to be as effective as Germall Plus esp. vs Gram negative bacteria.  Organic acids require an appropriately acidic pH and are weak preservatives, esp re. Gram negative bacteria.  Natacide is a combination of unidentified (unknown?) “natural” materials.  Even if effective - you’re offered no assurance that batch to batch compostions will be identical to that you qualified. 
Why not use phenoxyethanol in combination?