The U.S. Food and Drug Administration (FDA) includes gluconolactone (glucono delta-lactone), calcium gluconate, copper gluconate, ferrous gluconate and manganese gluconate on its list of direct food substances affirmed as Generally Recognized as Safe (GRAS). The FDA considers sodium gluconate GRAS for use in food as a sequestrant, and zinc gluconate GRAS for use in food as a nutrient. Ferrous gluconate is also permitted for use in food as a colorant exempt from certification.

FDA: Link to Code of Federal Regulations for gluconic acid and its salts

• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…
• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…
• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…
• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…
• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…
• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…
• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…

As part of the Organization for Economic Cooperation and Development (OECD) High Production Volume (HPV) chemical program, safety information available on gluconolactone, gluconic acid, sodium gluconate, calcium gluconate and potassium gluconate was reviewed. These compounds were not skin or eye irritants, nor were they skin sensitizers. Mutagenicity and reproductive and developmental toxicity data were negative. The reviewers concluded that gluconic acid and its derivatives were of low priority for additional work.

Link to the OECD summary: http://www.chem.unep.ch/irptc/sids/oecdsids/gluconates.pdf

Gluconic acid, gluconolactone, calcium gluconate, cobalt gluconate, copper gluconate, ferrous gluconate, lithium gluconate, magnesium gluconate, potassium gluconate and sodium gluconate may be used in cosmetics and personal care products marketed in Europe according to the general provisions of the Cosmetics Regulation of the European Union. Water-soluble zinc compounds, including zinc gluconate, are permitted to be used in cosmetics and personal care products at a maximum concentration of 1% zinc (see Annex III). Barium salts (excluding barium sulfide and barium sulfate) such as barium gluconate are not permitted to be used in cosmetics and personal care products in Europe (see Annex II).

Link to the EU Cosmetic Regulation: http://europa.eu/legislation_summaries/consumers/product_labelling_and_packaging/co0013_en.htm