Years ago, many avoided citric acid due to potential organic growth and molding issues. Today, citric acid has improved leaps and bounds with new formulations for biocides to prevent any organic growth in solution. See our complete write up on the advancements of citric acid (specifically Citrisurf). These new advancements in citric acid have allowed smaller manufacturers which had little to no experience with chemical handling and processing to bring their passivation needs in house. Today, many companies are taking a second look at citric acid due to its ease of chemical handling & disposal and safe for employee exposure all of which are more difficult with nitric acid.