According to a recent study, early 20th-century London fishmongers provided a creative solution for the problem of foodborne typhoid transmission.
The issue was that shellfish
acted as vectors for waterborne diseases … Once the connection was understood, consumers alone could have substantially reduced typhoid deaths by consuming far fewer shellfish.
Instead, a prominent fishmonger company
used the Billingsgate [fish] market to help high-quality sellers signal the quality of their products by sampling and testing harvest sites, banning sales from known contaminated areas, and requiring vendors to purchase shellfish cleaning services.
This strategy meant that
consumers who were willing to risk their own quality control could purchase shellfish for a lower price from traders who did not transit through Billingsgate, while those willing to pay a premium for third-party quality control purchased shellfish through Billingsgate.
Profit-motivated companies can create public goods.
Cross-posted from Substack.