In case you missed it, just before Christmas, the US Food and Drug Administration proposed a new regulation that calls into question the growing use of antimicrobial chemicals used in a wide array of products, including building materials. HBN has reported since 2010 on how the safety and the efficacy of adding antimicrobials to everyday products has been consistently challenged by independent investigations.
The Centers for Disease Control and Prevention (CDC) concluded a 2003 comprehensive study of infection control practice with the statement that "No evidence is available to suggest that use of these [antimicrobial] products will make consumers and patients healthier or prevent disease. No data support the use of these items as part of a sound infection-control strategy."
Kaiser Permanente similarly concluded in a December 2006 position statement that "[w]e do not recommend environmental surface finishes or fabrics that contain antimicrobials for the purpose of greater infection control and the subsequent prevention of hospital acquired infections." KP states that there is "no evidence that environmental surface finishes or fabrics containing antimicrobials assist in preventing infections."
One of the most widely used antimicrobials is Triclosan, which is sold under trade names such as Microban and BioFresh. The World Health Organization included Triclosan in its 2013 state-of-the-science report on endocrine-disrupting chemicals. The Centers for Disease Control found Triclosan in 75% of Americans tested, with levels rising from 2003 through 2010. Doctors from Johns Hopkins concluded in 2012 that these levels of Triclosan in the human body "were significantly associated with allergic sensitization."
Our Pharos Project researchers have identified Triclosan as both a potential asthmagen, and a persistent, bioaccumulative substance that can build up in humans, and when released to the environment, has been found in species as diverse as earthworms and bottlenose dolphins. Under certain conditions, Triclosan can break down in the environment into a group of dioxins – a class of chemicals known as potent carcinogens and endocrine disrupters. Additionally, Pharos Project research into Triclosan process chemistry found dioxin residuals as a common contaminant in this antimicrobial.
The FDA's proposed rule targets hand-soaps but will likely impact the growing array of antimicrobial products such as doorknobs, countertops, engineered wood floors, carpet tiles, paints, and wallcoverings. If enacted, the proposed rule will require manufacturers to prove that antimicrobials they add are safe and effective, responding to concerns from the many independent experts that say they are neither. Indeed independent experts fear that the ubiquitous use of antimicrobials may put people at greater risk as "superbacteria" develop resistance to the products. For this reason, the Canadian Medical Association has called for a ban on antimicrobial chemicals in ordinary consumer products.
The Triclosan story underscores the need for manufacturers to fully disclose building product contents so that architects, designers, building owners and occupants can make informed decisions about avoiding hazards while the regulatory agencies muddle through. The antimicrobial products specified in construction documents today with the intention of promoting healthy building, could be perceived quite differently in years to come. The FDA's action on antimicrobials comes some 35 years after it initiated an inquiry into Triclosan, and only after the agency settled a lawsuit with the Natural Resources Defense Council. That settlement requires the FDA to conclude this rulemaking . . . by 2016. In the meantime, using our Pharos Building Product Library, it is possible to identify products that contain Triclosan and to screen product lists to avoid antimicrobials and other biocides.
 See discussion, Full Disclosure Required: A Strategy to Prevent Asthma Through Building Product Selection, pp. 35-36, footnote 97.
 See discussion, Full Disclosure Required: A Strategy to Prevent Asthma Through Building Product Selection, pp. 35-36, footnote 96.