Skip to main content

Homosalate vs Recombinant Bovine Somatotropin: which is worse?

Quick answer: Recombinant Bovine Somatotropin carries the heavier risk profile. Homosalate is restricted in the EU and allowed in the US; Recombinant Bovine Somatotropin is in the EU and in the US.

PropertyHomosalateRecombinant Bovine Somatotropin
EU statusRestricted
US statusAllowed
Risk levelmedium
Banned inEuropean Union, Canada, Japan, Australia, New Zealand
Restricted inEuropean Union
Categoryuv filteradditive
Where it hidessunscreen, SPF moisturizer, SPF foundation

What is Homosalate?

Homosalate is an organic UV filter that absorbs UVB radiation.

What is Recombinant Bovine Somatotropin?

Recombinant bovine somatotropin (rBST) is the synthetic version of bovine growth hormone (BST), naturally produced by the pituitary gland in cattle. The recombinant version is produced using genetically engineered bacteria and is injected into dairy cows to increase milk production by 10-15%. Brand name: Posilac.

Documented risks

Homosalate: A suspected endocrine disruptor; the EU limits it to 7.34% in face products (2025), well below typical US concentrations.

Recombinant Bovine Somatotropin: See recombinant-bovine-growth-hormone-rbgh for full detail. Key concerns: rBST elevates IGF-1 in milk; elevated blood IGF-1 is associated with breast, prostate, and colorectal cancer risk in epidemiological studies. Animal welfare: increased mastitis (up to 25-50% higher rates), lameness, and antibiotic use. The Codex Alimentarius Commission declined to endorse rBST safety MRLs in a historic 33-29 vote. Health Canada rejected rBST approval in 1999 after finding it caused significant animal health problems requiring increased antibiotic use.

Got either one in your pantry?

Scan a barcode and we'll flag both Homosalate and Recombinant Bovine Somatotropin (plus 200+ other ingredients banned overseas).

Scan free →
Sign up free — 5 scans every day →