Most of the information is used to improve the user experience and to target advertisements to support a free business model, Huesch writes, but “[w]ere such risks to be realized, the ramifications could span embarrassment, discrimination in the labor market or the deliberate decision by marketers not to offer or advertise particular goods and services to an individual, based solely on the companies’ privately gathered knowledge.”

Huesch downloaded free privacy software as well as a commercial program that detects hidden traffic from a user’s computer on the websites of third parties and searched for the terms “depression,” “herpes” and “cancer.” The free privacy tools detected cookies or other “tracking elements” in 13 of 20 sites, and the commercial program found that seven actively sent search terms to third parties.

Huesch notes that traditional health privacy concerns have revolved around medical records but that much health-related information is generated in Internet searching.