Biocides Regulation Impacting Coatings in the United States: An Overview

Under the (Federal Insecticide Fungicide and Rodenticide Act (FIFRA), the U.S. Environmental Protection Agency (EPA) is required to review registered biocides every 15 years to evaluate associated risks and benefits of use based on current science. Throughout the agency’s most recent round of biocide (antimicrobial) registration reviews the American Coatings Association (ACA) has engaged with EPA, given potential disruptive changes to the use of biocides in the coatings industry.

EPA is expected to complete reviews of biocide (antimicrobial) registrations over the next two years. EPA determinations resulting from EPA review could result in labeling changes for paints and other formulated products containing biocides, decreased biocide use limits and/or canceled authorizations for use.

Biocides in paints and coatings are used to prevent microbial growth and degradation of paint film during production and storage prior to use and after application in the dry film. Increasingly, paint products have embraced waterborne technology to develop low VOC emitting paints, requiring the use of “in-can” preservatives. Without these, the paint can spoil, and in extreme cases, microbial decomposition can generate gases that rupture containers. Certain biocides are also used to disinfect equipment or as a corrective additive after formulation.

Of the hundreds of biocides currently under review, EPA identified some 40 biocides that are relevant to paints and coatings (EPA Registration Review Action Database is available online and provides a searchable database by biocide name for latest related actions).

As a key example, ITAs (isothiazolinones) are commonly used in paint. ITAs include the biocides known as OIT, BIT, MIT, CMIT and CMIT/MIT in mixture. EPA has stated it will release Proposed Interim Decisions (PIDs) for ITAs around October 2022. EPA typically releases PIDs after completing risk assessment, to announce proposed risk mitigation strategies. PIDs are subject to a 60-day public comment period, though typically EPA does not modify the draft PID before finalizing it. EPA is also required to consider benefits of biocide use when developing risk mitigation strategies proposed in a PID.

Proposed Changes and Industry Impact

As EPA developed risk assessments for ITAs and other biocides used in the paint and coatings industry over the past two years, ACA has submitted multiple sets of comments to the agency, and biocide manufacturers have also provided EPA with additional data to challenge EPA’s assessments. EPA commonly employs overly conservative data sets related to worker exposure and biocide handling in paint facilities. As such, industry and biocide manufacturers often are not aware of these assumptions until later stages, when EPA publishes draft risk assessments, placing industry in a reactive stance.

EPA also identifies risks associated with airless spray application of paints and coatings by consumers and professional painters. To address concerns about airless spray application by professional painters, EPA is proposing label changes on paint containers that prescribe respiratory protection, gloves, and other PPE. EPA will also propose lower use rates to address exposures to consumers caused by airless spray application. EPA is seeking industry input to develop a feasible industry PPE implementation and labeling program. In some instances, EPA will propose cancelation of use, as well.

In April 2022, EPA issued PIDs with proposed risk mitigation strategies for the biocides propiconazole and diuron while proposing cancelation of folpet’s authorization for use in paints. The PID for diuron includes proposed PPE implementation and labeling changes for paint containers. If finalized, this novel labeling requirement would serve as a template for other biocide PIDs, particularly for ITAs. EPA is seeking the paint and coatings industry’s input on this strategy.

The label changes contemplated by EPA would mitigate risk from airless spray application of paints with diuron by professional painters only. In addition, EPA is proposing a lower use rate for diuron to address consumer exposure. The label changes reference respiratory protection, training, fit testing, and medical surveillance currently required for spray application of paint under the U.S. Occupational Safety and Health Administration’s (OSHA) respiratory protection standard at 29 CFR 1910.134. EPA is proposing several label statements emphasizing that PPE is necessary to mitigate risk from biocides, going beyond OSHA’s requirement. EPA is also requiring painter’s hats, coveralls, and chemical-resistant gloves for professional spray application. EPA’s proposed label statements reflect these requirements.

EPA is also proposing an “industry stewardship program,” requiring the paint industry to develop an information and outreach program designed for professional painters. This would include communicating information related to PPE, fit testing, and medical surveillance of workers. Such a program could work in conjunction with professional painters’ associations.

ACA is working through its Preservation Product Stewardship Working Group to develop comments and meet with EPA on its proposals. EPA is open to changes related to how information is communicated, but strongly asserts the need for specified PPE and related training, fit testing, medical surveillance, etc. EPA also emphasizes the importance of communicating risks it has identified from biocide exposure. The alternative would be use cancelation.

ACA and Industry Response

ACA and biocide manufacturers are concerned that EPA has not incorporated an analysis of benefits properly prior to developing a risk mitigation strategy. ACA and industry have identified flaws in the underlying risk assessments, resulting in EPA’s PIDs having a high degree of inaccuracy. Inaccuracies are systemic, affecting most registration reviews, and ACA has provided EPA with presentations, comments and data related to workplace practices, benefits of biocides in paint and technical challenges related to paint formulation with biocides. At this writing, EPA has not effectively incorporated this information into its PIDs, sometimes citing its rigid procedures to revise data sets used in EPA risk assessments.

Biocide regulations directly impact industry products. As such, ACA and its members, biocide manufacturers and the American Chemistry Council have been collaborating, considering several options to address collective concerns. ACA continues to advocate industry’s perspective with EPA management, while urging Congress to exercise stronger oversight to address shortcomings in EPA’s implementation of FIFRA.