Public hearings are scheduled for the new chemical information regulations in California are planned for the end of January and mid February.

On Dec. 17, 2010, the California Office of Environmental Health Hazard Assessment (OEHHA) issued proposed regulations that would specify hazard traits, environmental and toxicological endpoints, and other relevant data that are to be included in the Toxics Information Clearinghouse (Clearinghouse) the California Department of Toxic Substances Control (CDTSC) will develop. The CDTSC will use information from the Clearinghouse to help identify chemicals of concern in consumer products as part of its Green Chemistry Program. The OEHHA will hold a public hearing on the proposed regulations on Jan. 31, 2011. Comments are due Feb. 15, 2011. More information is available online at this link.

This proposed regulation:

• Identifies and defines specific hazard traits;
• Identifies four general categories of hazard traits: toxicological, environmental, exposure potential and physical;
• Lists non-exclusive general categories of endpoints for each toxicological or environmental hazard trait;
• Lists non-exclusive general categories of "other relevant data" for each toxicological or environmental hazard trait;
• Shows how endpoint and other relevant data can be used as evidence in evaluating whether or not a chemical substance has a hazard trait; and
• Shows how data can be used to determine whether or not a chemical substance has an exposure potential or physical hazard trait.

The OEHHA’s August 2010 pre-regulatory draft regulations included several references to nanomaterials, defining "exposure potential hazard traits" to include "particle size or fiber dimension," including the existence of a chemical substance in the form of nanoparticles or fibers. The pre-regulatory draft regulations stated that a chemical substance has this hazard trait if it is in particle form in the nanoparticle size range (less than or equal to 0.1 micrometers (μm) in mass median aerodynamic diameter). Under the pre-regulatory draft regulations, physical hazard traits, which may affect human health or the environment, included a "nanomaterial hazard trait."  While the proposed regulations released on Dec. 17, 2010, include no references to nanomaterials or nanotechnology under exposure potential hazard traits, the OEHHA defines particle size or fiber dimension hazard trait. The proposed regulations define the particle size or fiber dimension hazard trait "as the existence of a chemical substance in the form of small particles or the propensity to form into such small-sized particles or fibers with use or environmental release." Evidence for the particle size or fiber dimension hazard trait includes, but is not limited to, measures of particle size less than or equal to 10 μm in mass median aerodynamic diameter for inhalation exposure; less than 10 μm in any dimension for dermal or ingestion exposure; or fibers with a 3:1 aspect ratio and a width less than or equal to 3 μm.

In the Initial Statement of Reasons, the OEHHA discussed some of the general comments it received "to explain why [the] OEHHA chose one path over another to develop specific provisions of the proposed regulation." In the section concerning the particle size or fiber dimension hazard trait, OEHHA states that its definition of particle size or fiber dimension includes "the potential for particles of 1 μm or less to pose an exposure potential hazard through multiple exposure pathways," and that "[v]ery small particles can also cross the walls of the gastrointestinal tract and the skin into the systemic circulation." For both of these statements, the OEHHA cites an article entitled, Safety Assessment for Nanotechnology and Nanomedicine: Concepts of Nanotoxicology. While the OEHHA may have removed explicit references to nanoparticles and nanomaterials from the proposed regulations, clearly, the office continues to have some concern regarding the risk they may pose.