Document ID: EPA-HQ-OPPT-2010-0572-0168
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2017-01-12T05:00Z

Reference 1  -  
Response to Comments to the Proposed Rule, Chemical Substances When Manufactured or Processed as Nanoscale Materials; TSCA Reporting and Recordkeeping Requirements
The chemical substances subject to this rule are chemical substances as defined in section 3 of TSCA.
December 27, 2016
Docket # EPA-HQ-OPPT-2010-0572
RIN 2070-AJ54

Comment 1:  Several commenters stated that TSCA applies to chemical substances not different physical forms or different particle sizes of chemical substances and that discrete forms or discrete physical forms are not "chemical substances" subject to reporting under section 8(a) of TSCA.  
Response: TSCA section 8(a) authorizes EPA to promulgate rules for submissions of such reports as the Agency "may reasonably require."  EPA believes that the information from this reporting will help EPA to determine whether chemical substances manufactured and processed at the nanoscale may exhibit behavior relevant to health and safety that is different from that of non-nanoscale forms of chemical substances. EPA thus has the authority to require reporting pertaining to different forms of chemical substances.   
Comment 2: Commenters stated that molecular structure, molecular identity, (one commenter defined molecule as the smallest fundamental unit of a compound that can take part in a chemical reaction), chemical substance definition, CAS Index name and chemical nomenclature have been used by EPA to distinguish chemical substances when administering TSCA.  Some of these commenters cited the premanufacture notice (PMN) program as an example of how TSCA applies these parameters to chemical substances.  The commenters asked why EPA had authority under section 8(a) of TSCA to require reporting for discrete physical forms of existing chemical substances while it defined chemical substances differently under section 5 of TSCA. 
Response: How EPA applies section 5 of TSCA for reporting of new chemical substances that are not on the TSCA Inventory may be different from reporting requirements for certain chemical substances at the nanoscale under Section 8 of TSCA. The parameters identified by commenters to distinguish chemical identity would not distinguish non-nanoscale forms of chemical substances from nanoscale forms of chemical substances.  EPA does not want to require reporting of non-nanoscale forms of chemical substances in this rule.  
Comment 3:   Several commenters stated that reporting on chemical substances that are nanoscale materials as described in the proposed rule was not justified on the basis of health or environmental risk; health or environmental hazards; or potential for exposure.  Reporting should not be based on a chemical substance being nanoscale or other arbitrary parameters. EPA should gather further information on properties or characteristics regarding hazards and exposures then focus reporting requirements based on these parameters.
Response:  TSCA section 8(a) rules are not based on risk or hazard findings.  In the proposed rule EPA discussed and referenced numerous studies illustrating the differences that exist between chemical substances and chemical substances manufactured in nanoscale forms.  Altering the size of a material from conventional particle size can produce unique or novel properties that are desirable for a variety of commercial applications. However, these unique or novel properties can also result in nanoscale materials presenting increased hazards to humans and the environment.  Because of the potential for unique and novel properties of nanoscale materials, EPA needs more information about chemical substances manufactured and processed at the nanoscale that are in commerce and available health and safety information.  Despite a voluntary reporting program for chemical substances at the nanoscale and research for its economic analysis, EPA has been unable to obtain reliable information about chemical substances at the nanoscale in commerce and any available hazard and exposure information regarding those nanoscale chemical substances. The purpose of the TSCA section 8(a) rule is to obtain this information and determine if any additional information gathering or risk reduction actions under TSCA are needed. 
Comment 4: Several commenters stated that the proposed information requests are outside those allowed by section 8(a) of TSCA. Commenters specifically identified material characterization including particle size and morphology, methods of manufacture, weight percent of impurities, environmental release information, general population, consumer exposure, risk management practices, and engineering controls.  One commenter wanted EPA to explain more clearly the basis of authority for requesting information that does not fall within the scope of the clear statutory authority of TSCA section 8(a). 
Response:   Section 8(a) gives EPA broad authority to collect information that the Administrator may reasonably require.  The categories in section 8(a)(2) are examples of what can be required under section 8(a). Section 8(a)(1) authorizes EPA to require reporting of such information with respect to chemical substances as the Administrator may reasonably require.  Although it contains limitations with respect to requirements to report with mixtures and to chemical substances manufactured in small quantities for experimentation, those limitations are not relevant to the requirements imposed by this rulemaking.  Section 8(a)(2) is best interpreted as listing examples of the kinds of information EPA can require reporting on under section 8(a)(1), not as limiting EPA's authority.  If Congress had intended to impose limitations on EPA's section 8(a)(1) authority, it would have added them to the limitations it included in section 8(a)(1).  EPA has always interpreted section 8(a) in this fashion, see 58 FR 63134 (November 30, 1993)  -  an interpretation that is supported by the legislative history of section 8(a), H.R. Conf. Rep. 94-1679, at 80 (1976); S. Rep. No. 94-698, at 22 (1976), H.R. Rep. No. 94-1341, at 42 (1976).   
      Further, the information required under the rule is consistent with the examples of information discussed in section 8(a)(2).  For example, requiring weight percent of impurities is analogous to byproducts (and EPA has long interpreted impurities to be within the scope of information that it may require under section 5(b)(1)(A) of TSCA, which incorporates section 8(a)(2); see 40 CFR 720.45(b)), material characterization including particle size and morphology is analogous to the molecular structure of chemical substances manufactured and processed at the nanoscale, environmental release falls under methods of disposal, while methods of manufacture, risk management practices, engineering controls, general population and consumer exposure fall under estimates of individuals who would be exposed (see 740.45(g)).  Adopting a narrow interpretation of section 8(a) rulemaking authority as suggested by the commenters would result in EPA being unable to require available characterization information that differentiates one form of a discrete reportable chemical substance from another form.  EPA would also be unable to require available estimates of the amounts of human and environmental exposure.
Comment 5: Several commenters supported the proposed data collection elements and use of the proposed form.  One commenter suggested additional details on reporting exposure and release information relating to publicly owned treatment works (POTW) including function and application categories to be used for reporting, and whether discharges were directly to sewers or from products without direct or common pathways for discharges. Another commenter suggested including experimental conditions when measuring zeta potential and other physical-chem properties.  
Response: Until EPA has further information on nanoscale forms of certain chemical substances in commerce that are being released to water and for which uses, the level of detail suggested by the commenter for POTW releases would be better addressed by additional TSCA actions or actions under other statutes.  If a person subject to the requirements of this rule is reporting physical-chemical properties, they would be required to submit available or reasonably ascertainable data regarding the physical-chemical properties which could include descriptions of the experimental conditions.  
Comment 6: Another commenter asked EPA to evaluate the need for the extensive data elements in the proposed reporting form which is different from previous TSCA section 8(a) rules and current TSCA section 5 reporting.  
Response:  When EPA considered the types of information to be reported, it considered the types of information that would be needed to achieve the goals identified in the proposed rule to find out about chemical substances at the nanoscale in commerce and information on how those chemical substances could be better assessed.  The information is important because it is the information EPA uses to assess risks to human health and the environment for chemical substances.  Some information collection elements were added specific to nanoscale materials that were not included in previous reporting requirements because those reporting requirements did not focus on information specific to nanoscale forms of chemical substances.
Comment 7: Several commenters proposed much more limited reporting of information because of potential burden with one commenter suggesting that companies report only some chemical identity and characterization information and characteristics exhibited by the chemical substance in its nanoscale form because of its size.  
Response:   Information required by this rule must only be reported if it is known to or reasonably ascertainable by persons subject to the rule.  This is defined to mean all information in a person's possession or control, plus all information that a reasonable person similarly situated might be expected to possess, control, or know.  Because TSCA section 8(a) rules do not require companies to develop or report information that is not known or reasonably ascertainable, the current descriptions for information to be reported such as chemical identity and characterization, human exposure and environmental release, test data, physical properties, and information specific to nanoscale materials will allow persons subject to the rule to identify and report available information without undue burden. 
Comment 8: One commenter asked EPA to clarify what was required to be reported for an overview of the life cycle of the nanoscale material while another commenter stated that EPA should evaluate the need for the reporting of the overview of life cycle.   
Response: EPA will remove the requirement for an overview of the life cycle in Section C of the reporting form, as that information duplicates information already identified in the reporting requirements of manufacturing, processing and use information in Sections A, B, and D.   
Comment 9:  Commenters suggested using the chemical data reporting (CDR) and the Preliminary Assessment Information Rule (PAIR) forms as a basis for reporting because of previous use in TSCA section 8(a) rules and because the proposed form goes beyond information allowed to be reported under TSCA section 8(a).
Response:  As described in the response to comment 3, all of the information required by this rule may be required under section 8(a). When EPA selected the form for reporting, it considered the types of reasonably ascertainable information to be reported that would be needed to achieve the goals identified in the proposed rule to find out about nanoscale materials in commerce and information on how those nanoscale materials could be better assessed.  The PAIR and CDR forms do not provide sufficient information to allow EPA to analyze the impact of chemical substances produced at the nanoscale.
Comment 10:  Many commenters stated the proposal gives too much discretion to interpret compliance obligations.  Commenters suggested clarifying the definition of unique or novel properties, adopting an alternative, or not using it at all.  One commenter noted that if the requirement that reportable chemicals exhibit unique and novel attributes due to particle size is removed from the definition, the rule would not differentiate genuinely new nanoscale materials from traditional legacy products in commerce.  Several commenters stated there should be some differentiation between genuinely new nanoscale materials in commerce and traditional products.  Two commenters supported the definition while one commenter supported a definition of 1-100 nm and unique or novel characteristics.
Response:  Based on these comments, EPA agrees that what is a reportable chemical substance should be better defined and clarified. EPA is finalizing the rule with further explanation of "unique and novel properties" as described in the National Nanotechnology Initiative's definition.  Some nanostructured materials are stronger or have different magnetic properties compared to other forms or sizes of the same material. Others are better at conducting heat or electricity. See www.nano.gov. They may become more chemically reactive or reflect light better or change color as their size or structure is altered.  A property is novel when it is different from the properties associated with other forms or sizes of the same chemical substance.  As also noted on www.nano.gov, when particle sizes of solid matter in the visible scale are compared to what can be seen in a regular optical microscope, there is little difference in the properties of the particles. But when particles are created with dimensions of about 1 - 100 nanometers, the materials' properties can change significantly from those at larger scales.  See also comment 11 and the response for further clarification on what is considered a reportable chemical substance. 
      For purposes of this rule, EPA is defining unique and novel properties to include an element of intent, meaning that those properties are the reason why the chemical substance is manufactured in that form or size.  The rule includes a definition of unique and novel properties in the definitions section of the regulatory text (See 704.20(a)). Unique and novel properties means any size-dependent properties that vary from those associated with other forms or sizes of the same chemical substance​, and such properties are a reason that the chemical substance is manufactured or processed in that form or size.  In order to be reportable it's not sufficient that a chemical substance contains particles in the size range of 1-100 nanometers; it must also have a size-dependent property different from properties at sizes greater than 100 nanometers and those properties are the reason that the chemical substance is manufactured or processed in that form or size.  Intentionally manufacturing or processing nanoscale gold so that it exhibits a red or purple color instead of a yellow color would create a unique or novel optical property seen at the nanoscale.  Such a change would likely result in changes of other properties, such as specific surface area which can result in different health and safety impacts.  Unique and novel properties which impact performance generally cannot be isolated from concurrent changes in properties that impact biological systems. For example, see the discussion in Unit II.B. of the proposed rule of the range of biological impacts of nanoscale materials. EPA is exempting certain biological materials, in part, because they do not exhibit different size-dependent properties in the size range of 1-100 nanometers.   
Other chemical substances, including as an example some chemicals that commenters  proposed that EPA exempt from reporting, such as pigments, polymers, and polymer dispersions, could be manufactured in nanoscale forms that both exhibit unique and novel properties and in forms that do not. In the concept paper for the NMSP (Ref. 10), EPA stated that many polymers or oligomers, particularly linear or planar polymers, should not be reported even though they have dimensions in the nanoscale.  Those polymers did not demonstrate size-dependent properties.  The paper did note that when conditions of polymerization or post-reaction processing create free particles that fit the general description of "engineered nanoscale material" those chemical substances should be reported under the NMSP.  Please also refer to the comment and response to comment 12 regarding the difference between enhanced and novel properties.
Comment 11:  Several commenters also suggested a better definition of trace amounts, stating that the term is not definitive and gives too much discretion to interpret compliance obligations.  The commenters suggested including a numerical value to define trace amount.  Most commenters did not suggest a specific value although one commenter noted the original definition of the Agency's draft proposed rule submitted to OMB would have required reporting for those substances containing >=10% particles in the range of 1-100 nm while another commenter suggested using a numerical value of less than 10% of particles as trace amount that would not be considered to be a reportable chemical substance.  Commenters asked EPA to clarify if particle size was to be determined by weight, volume, or count.  One commenter stated that EPA should not use weight based criteria to determine particle size as that measurement is sometimes skewed by the inclusion of very large particles.  Several other commenters suggested using weight based criteria to identify particle size but did not give any reasons why. 
	Response: Chemical substances manufactured or processed at the nanoscale that contain incidental amounts of particles in the size range of 1-100 nanometers are not reportable chemical substances.  EPA used trace amounts in the proposed rule to define this concept.  However, based on the public comments to more clearly define trace amounts including several comments to establish a numerical cutoff, EPA is instead using a numerical value of less than 1% of particles from 1-100 nm by weight to more clearly define those chemical substances that would not be reportable. EPA has chosen this number because it is the percentage cut-off used in OSHA's hazard communication standard for all chemicals substances that are not OSHA carcinogens (for which there is a 0.1% cut-off) (Ref. 11).  This 1% cut-off is a level that industry has used to identify chemicals in safety data sheets (and previously in material safety data sheets.)  Industry is already using this cut-off to identify at least some nanoscale chemical substances, e.g., carbon nanotubes in mixtures.  EPA is using the weight based method for measuring particles even though that measurement is sometimes altered by the presence of very large particles because it is the most widely use method and more data will be available.  The final rule does not require reporting for any chemical substance where less than 1% percent of the particle size distribution by weight is less than 100 nanometers.   
Comment 12: Commenters noted that enhanced properties are not the same as unique and novel properties and asked EPA to clarify the definition of enhanced property and replace it with "novel" in section C.5. of the reporting form to be consistent with the definition of nanoscale material. 
Response: Enhanced properties are generally described as increased reactivity or surface area when particle size decreases.  While reactivity and surface area increase, there is often little difference in the intrinsic properties of the particles in ranges above 100 nanometers.  When particles are created with dimensions in the 1 - 100 nanometer range, the materials' properties can change significantly from those at larger scales.  EPA agrees that not all enhanced properties are unique or novel.  For example, grinding or engineering pigments for better performance which results only in incidental amounts of particles between 1-100 nm would not constitute a nanoscale material with unique or novel properties.  Grinding or engineering pigments for better performance which results in almost all particles that are less than 100 nm would constitute a nanoscale material with unique or novel properties. EPA will replace the word enhanced with novel in section C.5. of the reporting form. 
Comment 13: One commenter suggested that "EPA should use the same definition of nanomaterials that was applied in the Nanoscale Materials Stewardship Program ("NMSP") to identify the volumes and uses of nanoscale substances currently in commerce and then use this information to identify those substances of concern for which the collection of data on those materials is warranted"  The commenter stated "such an approach by EPA would prevent confusion and unnecessary reporting because of the vague terms and concepts of exhibit unique and novel characteristics or properties because of their size."
Response:  The NMSP did not define nanoscale materials.  It described the types of chemical substances that could be nanoscale materials and the types of chemical substances that generally were not nanoscale materials.  This approach would therefore be too vague for persons to determine whether they are subject to the rule.  Because it does not identify which chemical substances are subject to reporting, EPA cannot use that approach for regulatory requirements.
Comment 14:  One commenter stated that EPA should use the ISO TS 27687 definition of nanomaterials for the definition of reportable chemical substance because it is an internationally recognized definition of nanomaterials and distinguishes between two subgroups, nano-objects and nanostructured materials. 
Response: The ISO definition of a nanomaterial is a material with any external dimension in the nanoscale or having internal structure or surface structure in the nanoscale.  That definition would include chemical substances that were not manufactured or engineered for size-dependent properties and contain particles greater than 100 nm.  EPA's definition of a reportable chemical substance is not intended to include those types of chemical substances. 
Comment 15:  Several commenters asked EPA to clarify the objects and collections of objects to which the 1-100 nm measurement applies.  In other words does that mean any form with particles 1-100 nm or does that include aggregates and agglomerates greater than 100 nm but based on primary particles less than 100 nm?  	
Response:  Chemical substances required to be reported would include any form with particles 1-100 nm but would not include aggregates or agglomerates greater than 100 nm even if they contain primary particles less than 100 nm.  EPA has modified the description of particles that would be subject to reporting in the definition of reportable chemical substance to better reflect this understanding.  The language in reportable chemical substance now reads. "..where any particles, including aggregates, or agglomerates."
Comment 16:  A commenter asked "Is it EPA's intention to require reporting on large molecules within the size range of 1  -  100 nm, which are not normally considered to be nanoscale materials (for example, monomers, polymers, colloids, etc.).  The commenter also asked "Are polymers or metals attached to a ligands which are larger than 1 nm in size also considered a nanoscale material for reporting."
Response:  In order to be a reportable chemical substance, the chemical must not only be a particle in the size range of 1-100 nanometers.  It must also have a unique or novel property, which is any size-dependent property that varies from those associated with other forms or sizes of the same chemical substance​, and such property is a reason that the chemical substance is manufactured or processed in that form.  As described in the example cited in Comment 10, there are examples of monomers, polymers, and colloids that are not reportable chemical substances.   Large molecules and chemicals attached to ligands greater than 1 nm that do not meet the definition do not need to be reported unless they form particles that meet the definition of a reportable chemical substance. 
Comment 17:  One commenter stated that "We have experienced cases where the Chemical Abstract Service (CAS) has not provided industry with a new registry number for a nanoscale form of an existing CAS‐designed material. Will EPA provide guidance to industry in these cases?"
Response:  EPA will provide guidance to industry but it will focus on the definition of a reportable chemical substance and the properties of the nanoscale material.  CAS does not issue a different CAS registry number for different nanoscale forms of the same chemical substance and EPA does not use CAS registry number to identify different nanoscale forms of the same chemical substance.  Whether a CAS number is assigned or not will not affect whether a chemical substance should be reported.  
Comment 18: One commenter noted that ".. nanoscale materials larger than the arguably somewhat arbitrary cut-off of 100 nm may also pose unique health or environmental concerns compared to bulk substances. The same commenter stated "While we appreciate the pragmatic need to establish specific size parameters for a Section 8(a) reporting rule, we encourage the Agency not to limit itself to materials <100 nm as it works towards characterizing the risks of nanoscale materials in the future." 
Response:   EPA acknowledges that nanoscale materials greater than 100 nm may have different properties unique to health or environmental concerns.  For this rule, EPA chose the generally accepted range of 1-100 nm to gather information on certain chemical substances in commerce as a starting point and will consider in the future potential risks from nanoscale materials greater than 100 nm.  EPA believes that using a specific generally recognized size range will result in more useful data than if a less specific parameter were used.  The commenter did not suggest an alternative size range or other parameter to be used.  EPA reiterates that 1-100 nm is a commonly recognized size range for nanoscale materials. 
Comment 19:  A variety of commenters stated that EPA should add additional exemptions for biological materials such as enzymes, lipids, carbohydrates, peptides, polypeptides, nucleotides, liposomes, antibodies, viruses, virus-like particles, viral based products, organelles, and microorganisms.  The commenters stated that the additional biological materials should be exempted for the same reason EPA proposed to exempt DNA, RNA, and proteins, that the additional biological materials did not exhibit properties as a function of their size range. 
Response:  Because the other biological materials meet the same criteria that EPA identified in the proposed rule, EPA is adding an exemption for enzymes, lipids, carbohydrates, peptides, liposomes, antibodies, viruses,  and microorganisms in the final rule.  The properties of all the exempted biological materials are not a function of the size range per se which can be in the nanoscale but rather of the precise nucleotide sequence (in the case of DNA and RNA), shape, and complex biological structures (living cells).
Comment 20:   Several commenters identified additional possible exemptions for organic and inorganic pigments and dyes because they are well understood or characterized and present low risk and low potential for exposure.  Commenters also stated that most organic and inorganic pigments do not meet the definition of particles of 1-100 nm and a unique or novel property and that some forms typically exist in the 1-100 nm range.
Response: A reportable chemical substance is not just a substance containing particles in the size range of 1-100 nanometers; it must also have a size-dependent property different from properties at sizes greater than 100 nanometers.  Organic and inorganic pigments and dyes could be manufactured in nanoscale forms that both exhibit unique and novel properties andin forms that do not.  If a chemical substance does not exhibit unique and novel properties, then no reporting would be required. EPA lacks information demonstrating minimal risk and exposure for nanoscale forms of organic and inorganic pigments and dyes that would be subject to reporting.  EPA is not including an exemption for these chemical substances because it would exempt some of the chemical substances at the nanoscale in commerce for which EPA is collecting information on health and safety effects which would allow EPA to better assess and manage risks of nanoscale materials.
Comment 21:   Several commenters identified additional possible exemptions for polymers including polymer dispersions because they are well understood or characterized and present low risk and low potential for exposure.  Commenters also stated that polymers and polymer dispersions do not demonstrate a unique or novel property although they often exist in the 1-100 nm range.  Commenters suggested that EPA include an exemption for polymers and polymer dispersions to be consistent with the polymer exemption under section 5 of TSCA. 
Response: A reportable chemical substance is not just a substance containing particles in the size range of 1-100 nanometers; it must also have a size-dependent property different from properties at sizes greater than 100 nanometers.  Polymers and polymer dispersions could be manufactured in nanoscale forms that both exhibit unique and novel properties andin forms that do not.  If a chemical substance does not exhibit unique and novel properties, then no reporting would be required.  EPA lacks information demonstrating minimal risk and exposure for nanoscale forms of polymers and polymer dispersions that would be subject to reporting.  The polymer exemption under TSCA section 5 is not based on whether the polymer is a chemical substance at the nanoscale subject to reporting and does not include all polymers.  EPA is not including an exemption for polymers and polymer dispersions because it would exempt some of the chemical substances at the nanoscale in commerce for which EPA is collecting information on health and safety effects which would allow EPA to better assess and manage risks of nanoscale materials.
Comment 22:   Several commenters identified additional possible exemptions for chemical substances used in adhesives, coatings and sealants and chemical substances when they are embedded in a polymer matrix or incorporated into a formulated product such as adhesives, cement, ink, coatings, glass, paint, plastic and rubber.  Commenters stated these types of materials are well-understood or characterized and present low risk and low potential for exposure.  Commenters also noted TSCA section 5 regulations such as SNURs which exempted requirements for carbon nanotubes, silica, and pigments when incorporated into polymer matrices. 
Response: Most of the activities described by commenters for exemption would only require reporting for a reportable chemical substance before it is incorporated into a formulated product or polymer matrix.  Reporting would not be required by persons who use the formulated product or polymer matrix.  EPA lacks information demonstrating minimal risk and exposure for formulated products or processing a chemical substance in a nanoscale form into a polymer matrix.  EPA is not including the proposed exemptions because they pertain to chemical substances at the nanoscale in commerce for which EPA is collecting information on health and safety effects which would allow EPA to better assess and manage risks of nanoscale materials.
 Comment 23:  Several commenters proposed limited or no reporting for other nanoscale materials such as carbon black, silica, titanium dioxide, and nanosilver based on the proposed exemption for nanoclays and zinc oxide.  The commenters asked EPA to better define the criteria it used to exempt nanoclays and zinc oxide as well-characterized so that it could be applied to these chemical substances.  Several commenters also described the hazards and exposures of these chemical substances as well-characterized.  Several commenters stated that EPA should not exempt zinc oxide and nanoclays as EPA had not identified and made available the data that demonstrated why they are well-characterized.  
Response:  EPA has decided to not exempt nanoclays and zinc oxide from reporting.  When considering the comments to exempt other chemical substances based on its proposed exemption for zinc oxide and nanoclays, EPA realized that it had given too much weight to the available information on zinc oxide and nanoclays.  While there is some available information on these chemical substances, EPA does not consider the available information sufficient  to extrapolate this information to all other forms of these chemical substances to exclude information collection under TSCA.  Further, this limited information is not a sufficient basis to create a broader exemption by analogy for other chemical substances.  Thus, even for chemical substances manufactured as nanoscale materials that could be described as a group as well-characterized or demonstrating low hazard, EPA lacks information on how much and what type of specific nanoscale materials are in commerce and what kind of information is available to assess the properties that can impact health and safety and thus potential risks of those nanoscale materials.  The chemical substances that commenters and EPA stated were well characterized could be manufactured in nanoscale forms that both exhibit unique and novel properties andin forms that do not.  EPA is not exempting from reporting any of the chemical substances proposed by commenters, including zinc oxide and nanoclays because doing so would exempt some of the nanoscale materials in commerce for which EPA is collecting information on health and safety effects which would allow EPA to better assess and manage risks of nanoscale materials. See also the response to comment 25. 
Comment 24:  A commenter also suggested exempting nanocellulose because it was also as well characterized as the chemical substances described in comment 23 and that available data for commercial forms of nanocellulose demonstrate low hazard and risk.
Response:  EPA is not exempting nanocellulose for the same reasons described in comment 23.  The type of information described by the commenter is the type of information EPA seeks to collect, to identify nanoscale materials in commerce and to provide available information useful in the assessment of those materials. 
Comment 25: Several other commenters disagreed with exempting nanoclays and zinc oxide from reporting because EPA did not give an adequate basis for exempting them and even if current forms are well-characterized why exempt future new forms without information on those new forms.  One commenter gave an example of needing more information on new forms of zinc oxide to address water quality issues from additional use.  
Response:  As noted in the response to comment 23, EPA will not finalize the proposed exemption of zinc oxide and nanoclays.  The rule will also require reporting of any new future nanoscale forms of those chemical substances. 
Comment 26:  Some commenters proposed a volume cutoff below which no reporting is required such as 10 or 100 kg.   
Response: EPA is not adopting a volume cutoff below which reporting is not required, in order to obtain a better understanding of nanoscale forms of chemical substances in commerce including those with high added value but low production volume.  One time gathering of information on even low volume nanoscale materials could result in data relevant to their environmental and health effects.  
Comment 27:  Several commenters stated that EPA should exempt naturally occurring or mined nanoscale materials. One commenter noted that CDR regulations exempt naturally occurring chemical substances as described at 40 CFR § 710.4(b).  Several commenters also stated naturally occurring nanoscale materials should be exempt from reporting as they do not meet the criteria of the definition of "manufactured or processed."  Another commenter suggested limiting reporting to engineered nanomaterials as they are "generated for a specific function" or "deliberately manipulated."
Response:  EPA did not exempt naturally occurring materials or limit reporting to chemical substances engineered at the nanoscale because some of these chemical substances meet the criteria of a reportable chemical substance and some of them do not.  These chemical substances must be reported only if they meet the definition of containing particles in the size range of 1-100 nanometers and a size-dependent property different from properties at sizes greater than 100 nanometers.  EPA expects that reportable chemical substances would usually be the result of processing of naturally occurring or mined materials by manufacturers and processors
Comment 28:  A commenter stated that EPA should add an explicit exemption for nanoscale substances that are unintentionally generated during manufacturing and processing. Another commenter asked EPA to clarify if it matters if a nanoscale substance is intentionally added versus accidentally formed.  
Response:  If a nanoscale chemical substance is unintentionally generated or added and not intended to be part of the commercially manufactured or processed chemical substance, it may be considered a byproduct or impurity and would be exempt under 40 CFR 704.5(b) or (c).  If a nanoscale chemical substance is unintentionally formed but is considered to be part of the function of the commercial product, it would be a reportable chemical substance.  There are examples where a chemical substance is intentionally produced, but unintentionally produced at the nanoscale, and the manufacturer knows that it contributes to the function of their product.  In those cases, where a company knows about its functionality, the chemical substance is still subject to TSCA reporting requirements. See, for example, EPA's PMN regulations at 40 CFR 720.30(h)(2), which exempts from reporting a byproduct not used for commercial purposes, but retains the reporting requirement if the byproduct is used for commercial purposes.  The rule does not require a company to determine the functionality of every impurity or byproduct.  A company is required to report that chemical substance when it knows the chemical substance has commercial functionality. 
Comment 29:   Several commenters asked EPA to clarify the exemption for chemical substances manufactured at the nanoscale as part of a film on a surface. EPA should more clearly differentiate the nanoscale structures in semiconductor devices from the discrete nanoscale materials that are reportable under the rule and  that the exemption should state ..."chemical substances manufactured or processed at the nanoscale as part of a film on a surface" because forming these types of film are often considered processing and not thought of as manufacturing.  Two commenters also suggested that EPA include specific techniques in the definition to make clear it is the nanoscale film less than 100 nm that is exempt.  The commenters stated "To achieve these refinements, the commenter recommends that the exemption language at 704.20(c)(1)(iii) be worded as follows: "Chemical substances manufactured or processed at nanoscale as part of a film on a surface, utilizing vapor or atomic layer deposition, ion implant, sputtering, diffusion, plating, spin‐on processing or other deposition technique."  This would help to clarify that the key to the exemption is the application of chemical substances to a surface "as part of a film," 
Response: As noted by the commenters who suggested modified language for this exemption, in many applications films less than 100 nm can be formed over a wide variety of surfaces.  In some cases, these films can be formed even though the chemical substances used to form the film are not nanoscale materials.  The purpose of the exemption is not to require reporting on films on a surface because those films do not exhibit size-dependent properties.  In those instances where the chemical substances that are used to form a film on a surface are nanoscale forms subject to reporting under the rule, the manufacturer or processors would report that they are used to form a film on a surface.  EPA is not including the language regarding techniques suggested by commenters because it does not want to limit or suggest the exemption is limited to specific techniques.  The exemption is directed to a chemical substance formed as a film regardless of technique.  Because "chemical substances manufactured at the nanoscale as part of a film on a surface" did not adequately describe the films on a surface exemption that was proposed and may also confuse manufacturers or processors who form a film using nanoscale chemical substances, EPA will change the wording of the exemption to state "chemical substances formed at the nanoscale as part of a film on a surface." 
Comment 30: Several commenters suggested that EPA not exempt chemical substances manufactured at the nanoscale as part of a film on a surface to obtain more data as it emerges.  The commenters either gave no explanation or assumed EPA's basis was low exposure and noted the potential for exposure from the constituents of films or coatings. 
Response:   While the rule does exempt chemical substances manufactured at the nanoscale as part of a film on a surface, EPA will nonetheless receive information on reportable nanoscale materials that are used to manufacture chemical substances at the nanoscale that are incorporated into such a film..  When EPA reviews the reported information the Agency can evaluate the data from that commercial activity.    
Comment 31: Several commenters stated that EPA cannot require information that violates the language under the Toxic Substances Control Act (TSCA) § 8(a) prohibiting "any reporting which is unnecessary or duplicative."  Commenters stated that requiring reporting of some of the information already reported to the NMSP would be duplicated especially the large amount of health and safety information submitted for broad classes of chemical substances such as silica and carbon black.  Commenters also asked EPA to explain why the proposed reporting requirements do not duplicate reporting required under CDR.  
Response:  The reporting required by this rule does not duplicate reporting EPA would receive under other TSCA regulations.  Chemical data reporting (CDR) under 40 CFR part 711 does not require manufacturers to distinguish reporting for different forms of chemical substances including nanoscale materials.  This rule also exempts reporting for chemical substances that are nanoscale materials that have already been reported under section 5 of TSCA since 2005 except for new discrete forms.  As noted in the interim report on the NMSP (Ref. 12), EPA received limited reporting on nanoscale materials in commerce. The reporting for nanoscale materials such as silica and carbon black gave an overview of the entire industry but not information on individual nanoscale materials.  A company reporting a silica or carbon black-based nanoscale material does not have to resubmit the information submitted under the NMSP.  However, any reporting of silica or carbon black nanoscale materials would need to include any health and safety information that company possesses for the specific nanoscale material it is reporting.  As already noted, CDR reporting does not distinguish between different nanoscale forms of chemical substances.  Several commenters stated that EPA needs more information on nanoscale materials in commerce.  EPA addresses more specific comments about information required by the rule in other response to comments.
Comment 32:  Several commenters noted that processors do not know about the particle size and other characteristics of formulations they process or use and should not be required to report.  Response: Reporting of information under TSCA section 8(a) is required only to the extent the information is known or reasonably ascertainable, and includes information that the Administrator may reasonably require.  This standard applies both to the extent of an entity's obligation to determine whether it is required to report, and to the extent of information any entity is required to report.  If processors do not know about specific physical properties of chemical substances, they must still take reasonable measures to ascertain the information that would determine whether they are subject to the rule. If processors do not know about specific properties such as particle size and other properties that would allow them to know if they are processing a chemical substance subject to the rule, it would be within the reasonably ascertainable standard to ask their suppliers for information that would enable to processor to determine whether the supplier is selling them a nanoscale material subject to reporting and if so provide them with what reportable information they have.  Their supplier is not required to provide any additional information to the processor but might provide other supporting information, for example, whether their supplier has reported or intends to report the chemical substance under this rule.  If the supplier provides information indicating that the substance is not reportable or if the processor lacks any other means of reasonably ascertaining whether the substance is reportable, the processor does not need to perform tests to determine whether the substance is reportable.  Information developed in the normal course of business or that the processor chooses to develop must also be used.  The processor may want to document the steps they took to determine if reporting was required.  Companies that purchase formulations but do not change or modify those formulations and only use them are not considered processors and are not required to report.  
      If the information provided by the supplier indicates that reporting is required, the processor is required to report information that is known or reasonably ascertainable, which may include information obtained from the supplier.  This would include situations where the processor may not know the exact chemical identity or some of its physical properties.
      The obligations imposed by the reasonably ascertainable standard are discussed more fully in the Chemical Data Reporting final rule, 76 FR 50816, 50829 (August 16, 2011),
Comment 33: Several commenters asked EPA to clarify if manufacturers and processors are only required to report available or reasonably ascertainable information does this mean they need to develop information to comply with the rule.  Other commenters asked EPA to clarify if manufacturers and processors need to develop information to comply with the rule.
Response: Manufacturers and processors are not required to conduct testing or develop information under this rule.  However, they are required to report information that is known or reasonably ascertainable. 
Comment 34:  Several commenters objected to imposing the same reporting requirements on both processors and manufacturers stating that some processors will not be aware of information known to manufacturers such as for example chemical identity, physical-chemical properties, byproducts, impurities, health effects data, and general population exposure.  In addition, the commenters speculated that processors may report uses and processes already reported by the manufacturer.  The commenters felt the reporting requirements place impractical or burdensome obligations on processors without collecting information that would serve the intended purposes of the rule when manufacturers were in the best position to report information required by the rule. Commenters suggested limiting reporting to only manufacturers or limiting the information to be reported by processors. 
Response: Processors are only required to submit information that is known or reasonably ascertainable.  In addition, processors may have access to pertinent information that manufacturers do not have access to.  Processors can often describe in greater detail how the nanoscale material is processed and used and any characteristics that change because of processing.  Details on the processing and use of nanoscale forms of chemical substances with unique or novel properties will give EPA a better understanding regarding how to assess those chemical substances and whether any further actions are warranted under TSCA.
Comment 35: One commenter noted that OSHA does not require particle size information and asked if EPA will work towards mandating reporting of this information to customers.
Response:  EPA would encourage manufacturers to inform their customers if they distribute a chemical substance subject to reporting for this rule so their customers would know they are also subject to reporting. 
Comment 36:  A commenter asked if processors of a chemical submitted as a PMN are required to report.  Another commenter stated that all manufacturers and processors should be exempt from reporting for a chemical substance already the subject of a section 5 submission, not just the original submitter. 
Response:  Only persons who submitted the section 5 submission after January 1, 2005 are exempt from reporting.  Other manufacturers and processors would still be required to report.  The additional information they would have on details of manufacture, processing, and use would not be duplicative reporting because that information would not be reasonably ascertainable by the PMN submitter.   
Comment 37: A commenter asked if a nanoscale substance is reported as a new chemical for one use but later has a different use from the one reported, would this require section 8(a) reporting.
Because this rule includes one-time reporting of nanoscale forms of chemical substances in commerce, new uses of reportable chemical substances do not require additional reporting.  However, if the person manufactures or processes a discrete form of the reportable chemical substance then that person would be required to report under this rule. 
Comment 38: A commenter asked if "reporting for mixtures is notifier-specific or substance- specific.  For example if a manufacturer reports and sells to 10 processors, does each customer report?"  
Response:  Reporting for mixtures is not required but is required for a reportable chemical substance in a mixture.  Any reportable chemical substance that is incorporated into a mixture or substrate would require reporting for manufacturing or processing of that chemical substance.  If a manufacturer sells a mixture containing a reportable chemical substance to multiple processors then each processor is also required to report.    
Comment 39: A commenter asked "would each manufactured material containing the nanoparticles throughout this supply chain all the way to the end use need to be separately reported, or would reporting of only the primary discrete nanoparticle need to be reported at the point of manufacture to avoid redundant reporting of the same primary material?"  The commenter also asked if this includes incorporation into articles and substrates.  
Response: Each manufacturer and processor in the supply chain would need to report reasonably ascertainable information on how the nanoscale form of the chemical substance is manufactured, processed or used throughout the supply chain.  The additional information they would have on details of manufacture, processing, and use would not be duplicative reporting because that information would not be reasonably ascertainable by the manufacturer.  Once a chemical substance has been incorporated into an article, no further reporting is required as persons that manufacture or process chemical substances as part of articles are exempt from reporting. 
Comment 40:  One commenter stated that EPA has publicly expressed misgivings about the value of processor reporting under TSCA. In March 2013, the Government Accountability Office issued a report on the TSCA program that recommended issuance of a Section 8 rule requiring reporting of exposure-related data by chemical processors.  The GAO report includes a letter from EPA responding to this recommendation. EPA questioned the value of processor data, noting that "processors" are not always end-users of products, and that end-users "often have little exposure-relevant data."
Response:  Because this rule focuses on chemical substances manufactured as nanoscale materials with unique and novel properties, processors are expected to have information on whether those nanoscale materials are handled differently than other chemicals or if the nanoscale materials have any additional characteristics because of processing details not known to manufacturers or end users.  This rule does not require reporting from end users unless the end users are also processors. 
Comment 41:  Some commenters noted how the CBI interests of downstream companies that supply confidential information to manufacturers may not be protected when manufacturers provide that information as part of their reporting but do not claim the information as confidential.  
One of the commenters stated that "The form that would be required under this proposed rule seeks highly detailed information from chemical suppliers about what they may know about their customers' businesses, technologies and operations. Unintentional public release of the intellectual property of customers would result in severe and substantial economic impacts to U.S.-based industry. The current CBI protection provisions in 40 CFR Part 704 and Part 2, were not designed with a scenario like the Nano Reporting Rule in mind and thus should be upgraded to protect the reasonable interests of downstream companies."  One commenter suggested procedures for addressing this issue such as EPA could review information regarding Industrial Sites Controlled by Others and on the Lifecycle Overview on the proposed reporting form.  "In conducting this review, EPA could also take into consideration the number of facilities that the reporter is characterizing (which would be identified on page 11) to determine whether the information reported is characterizing specific facilities or a more generalized description of a downstream industry. Looking at the specific entries on these few pages, EPA would determine whether a CBI claim "could be expected" by an affected business if that business knew that the information on these pages would be publicly disclosed."  Other commenters stated that "EPA should also include in the form instructions a statement that reporters should consult with their customers on these sections of the form and an explanation that reporters should assert CBI claims for information that they expect to be considered CBI by their customers."
Response: While 40 CFR 2.204(c)(2)(i) requires EPA to make an inquiry regarding CBI claims when "a company might be expected to assert a claim if it knew EPA proposed to disclose the information," EPA is generally not in a position to speculate concerning CBI claims that might be asserted by downstream or upstream companies.  Therefore it is properly up to the businesses involved to communicate regarding confidentiality. Once information has been received and not claimed as confidential, it may be difficult if not impossible to protect it.  EPA will add language to the form instructions that "You may want to consult with your customers or suppliers about the confidentiality of any information you report about them on this form." 
Comment 42:  There were numerous comments to not include the 135 day reporting requirement for new discrete forms.  This requirement was characterized by several commenters as de facto new chemical reporting.  The commenters noted it is burdensome, would adversely affect commercialization and was arbitrary as reporting before commercialization of an existing chemical was not part of TSCA 8(a) authority.  One commenter stated EPA should give a risk-based explanation for the proposed reporting.  Numerous commenters stated EPA should make clear when commercialization can begin  -  for example after notification to EPA or after 135 days.  Commenters offered alternatives such as 60 days before commercialization or up to six months after commercialization.  The 135 day reporting requirement was supported by several commenters who stated it would allow EPA time to evaluate the reported nanoscale materials and take any necessary actions under TSCA.   
Response:  EPA did not intend to create de facto new chemical reporting for new discrete forms of nanoscale materials, because the 135-day period is not a formal review-period that prohibits manufacture before the end of the 135-day period.  Rather, based on EPA's experience with the Premanufacture Notice (PMN) program, EPA believes that in most cases companies have the requisite intent to manufacture or process at least 135 days before manufacturing or processing will begin, and the rule requires reporting based upon this presumed intent. However, if a company does not form the requisite intent 135 days ahead of time, the company must report within 30 days of the formation of such an intent.  Moreover, if a company desires to begin manufacture or processing less than 135 days after the submission for this rule is made, the company is free to do so. There is no obligation upon the company to wait 135 days after reporting to manufacture or process. EPA is revising the language in 704.20(f)(2) to clarify that the rule does not prevent manufacturing before the 135-day period has passed. If the company changes its schedule or does not form the intent until a later time, it may wish to document supporting facts.  
	Further, the comments made EPA realize that the regulatory text as written in the proposal created a result unintended by the Agency (and not commented upon): because (1) the default period of 135 days is greater than the advance of periods required for various section 5 submissions, and (2) the reporting exemption for section 5 submissions in 704.20(c)(2) of the proposal would apply only where the company had already filed a section 5 submission, a company proposing to manufacture a discrete form of a reportable substance for which a section 5 submission had not been filed might conceivably be required to first file a section 8(a) report, followed by a section 5 submission. In such cases EPA only needs the section 5 submission, and sees no value in the additional burden of requiring a duplicative section 8(a) submission. Therefore EPA is adding a new subcategory of non-reportable chemical substances to 704.20(c)(1), for chemical substances that are not on the TSCA Inventory at the time reporting would otherwise be required, to clarify the Agency's original intent in the NPRM. If a reportable chemical substance is not on the TSCA Inventory a manufacturer only needs to submit a new chemical notification under section 5 of TSCA.
Comment 43:  Several commenters stated that the reporting requirement for discrete forms of existing chemicals is not reasonable or necessary.  One commenter stated that "The proposed reports and 135 day waiting period with no sunset, for an entire class of emerging technology, would establish a notification program for existing chemicals that takes longer, and is more burdensome, than for new chemical substances under section 5."  The commenter stated that it "does not agree with EPA's determination that this aspect of the proposal is consistent with existing Administration policy, and urges its withdrawal entirely" and that "has reviewed EPA's existing guideline for reporting nanoscale substances to the TSCA Inventory, and two policy statements issued by the White House Office of Science and Technology Policy. These policy statements have concluded that the U.S. regulatory framework as it exists today is sufficient to regulate nanomaterials."
Response:  As described in the response to comment 42 the reporting requirements in this rule serve only as a reporting program and do not regulate commercialization of existing chemical substances. As described in the response to comment 1, reporting requirements for discrete forms of chemical substance is consistent with TSCA section 8(a) authority.  The reporting requirements for discrete forms of reportable chemical substances will allow EPA to gather additional information on nanoscale materials in commerce when it becomes available and to determine if any further actions under TSCA are necessary. 
Comment 44:  Several commenters stated EPA should allow more time for companies to report chemical substances in commerce.  One commenter stated "we don't have enough time to prepare the report especially for first period (six months) because preparing the report will be a time consuming process for the company manufacturing several types of nanoscale materials." In order for any new reporting requirements of this rule not to coincide with reporting requirements of the 2016 CDR rule another commenter suggested "that any reporting obligations under this rule commence no earlier than September 30, 2017, one year after the 2016 CDR data reporting period closes"  
Response: Based on these comments, EPA will extend the period to report chemical substances in commerce to one year after the effective date of the rule.  This will allow companies time to familiarize themselves with the new reporting requirements and to comply with requirements if they have multiple reportable chemical substances.  It will also ensure that the reporting requirements of this rule do not coincide with the 2016 CDR reporting. 
Comment 45:  There is not standardized testing for the physical properties in the proposed rule identified for manufacturers and processors to determine if they qualify for the rule. EPA should identify test methods to be used to comply with the rule.  Many processors will not know to test for these properties.  EPA cannot require this testing until validated protocols are developed. 
Response:  Testing or developing new information is not required by the rule.  Only known or reasonably ascertainable information needs to be reported.  Companies are only required to report on known or reasonably ascertainable information.  See the response to comment 3 for guidance as to situations in which a company does not know about the physical properties identified in the regulation.  In the proposed rule, EPA supplied examples of testing guidelines that could be used for these types of properties should the company desire to do such testing.
Comment 46:  Commenters asked EPA to either reevaluate or justify the use of seven standard deviations as the numerical change in property values to determine the discrete form of a reportable chemical substance.  One commenter stated that "The scientific basis for the use of seven standard deviations as a cutoff for reporting is not presented in the proposed rule.  Therefore, it should either be justified or supplanted with a justified cut-off. The use of standard deviation as a measure of confidence in statistical conclusions is generally useful. It is assumed that the measured value is the mean of the values measured, although this is not stated. Also, is this cut-off of seven times the standard deviation for physicochemical values assumed to be based on a normal distribution?" One commenter stated EPA should reconsider seven times the standard deviation as the numerical change in property values to determine the discrete form of a reportable chemical substance because "This approach sets a very high bar: It would not only require potentially very large changes in size/properties to trigger new reporting, but it would also exclude from reporting even very large changes in size unless accompanied by a large change in properties  -  and vice versa." 
Response:  The standard deviation is a measure of how spread out a distribution of values are, in this case particle size distribution.  EPA is continuing to use seven standard deviation as it allows for natural variations in change for variable materials such as nanoscale materials.  When determining to use seven standard deviations, EPA attempted to balance how much variation to allow for discrete forms of a reportable chemical substance and whether companies have the analytical tools to make such distinctions.  Using this approach permits materials with wide or narrow ranges of variability to be treated in the same proportion.  Unless the physical property measurement already contains a measured mean and a distribution based on multiple measurements such as a particle size distribution, the mean should be assumed to be the measured value and a normal distribution should be assumed.   
Comment 47:  There were several suggestions to better align reporting with Canadian nanoscale materials reporting such as only identifying specific substances for reporting, only have manufacturers and importers report, the quantity and scope of materials covered, information to be reported and subsequent reporting requirements.  One commenter stated "... if the U.S. and Canadian approaches are not more closely aligned, the comparability of information and ability to move forward in a coordinated manner would be at risk and that the reporting burden on industry could be extremely high." Another commenter stated "The reporting burden on companies that are required to report to both governments will be extremely high unless the U.S. and Canadian approaches are aligned."
Response:  The commenters did not identify a specific reason why not aligning the proposals would be unduly burdensome other than the US approach required more information on more nanoscale materials for a longer period of time, nor did they suggest a way to align the different approaches.  EPA believes the approach it has taken is consistent with the intent of TSCA and believes an alignment solely for purposes of alignment would be arbitrary.  Because these rules were developed under different statues and review processes, EPA and Canada were unable to make additional changes to align the rules as they were being developed, proposed, and finalized.  EPA will continue to work with Canada to align, where appropriate, any additional information gathering or risk management activities.   
Comment 48:  One commenter asked EPA to enable submitters to authorize EPA to share CBI provided under this rule with Environment Canada and Health Canada. 
Response:  In order to continue work on sharing available information and to inform future alignment on activities pertaining to nanoscale materials, EPA will include in final rule the option to share information with Canada.  As suggested by the commenter the reporting form will include the option to authorize sharing of all CBI information with Environment and Climate Change Canada and Health Canada.  Any shared CBI would be subject to the CBI protection policies of those agencies.
Comment 49:  Several commenters supported the existing $4 million dollar small business exemption. Because of the uncertainty of hazards for nanomaterials, one commenter wanted a smaller dollar amount so that more small businesses would be required to report. Other commenters stated it should be increased to $9.5 million dollars to account for inflation since 1988 when the current small business amount of $4 million was established.  
Response:   Based on these comments and updated economic information, EPA is changing the definition of small business in the final rule to include any company with sales of $11 million dollars or less.  In suggesting EPA change the value to $9.5 million, the commenter assumed the original $4 million was promulgated in 1988. However, the $4 million was initially promulgated in 1984 (49 FR 45425) with a base year of 1983. Therefore, it is appropriate to inflate the $4 million from $1983 to $2015.  When accounting for inflation since 1983, EPA calculated the figure to be $11 million dollars.  
In proposing this definition, EPA provided notice and comment on the criteria for small manufacturers and processors subject to this rule, and consulted with the Small Business Administration (SBA)  in accordance with TSCA section 8(a)(3)(B). EPA's change to this definition is consistent with both public comments and the feedback we received from SBA.  
EPA recognizes that recent amendments to TSCA include a new and separate obligation under amended TSCA section 8(a)(3)(C), which requires EPA, after consultation with the SBA, to review the adequacy of the standards for determining the manufacturers and processors which qualify as small manufacturers and processors for purposes of TSCA sections 8(a)(1) and 8(a)(3). TSCA furthermore requires that (after consulting with the SBA and providing public notice and an opportunity for comment) EPA make a determination as to whether revision of the standards is warranted. In the Federal Register of December 15, 2016 (81 FR 90840) (FRL-9956-03), EPA sought public comment on whether a revision of the current size standard definitions is warranted at this time; announced EPA's initiation of the required consultation with the SBA, and provided its preliminary determination that revision to the currently codified size standards for TSCA Section 8(a) is indeed warranted. As part of this effort, EPA will review the adequacy of the standards for small manufacturers and processors in existing TSCA section 8(a) rules, including this one. Any changes resulting from the assessment will undergo consultation with SBA and will be proposed for notice and comment as required by TSCA section 8(a)(3)(C).    
Comment 50:  One commenter stated that "EPA also should implement a different, higher annual sales figure for small business processors in this rule" because "sales of the processed product can result in annual sales figures that will easily exceed the proposed small business threshold of four million dollars for an otherwise small business processing operation."  Another commenter objected to the change eliminating the production volume limit for the small business exemption suggesting to exclude producers of very small amounts because "The fact that nanomaterials may only be processed in small volumes points to the fact that the potential for exposure to man or the environment still remains low for these materials."
Response: As explained in the proposed rule, EPA does not believe that the production volume of chemical substances manufactured or processed as nanoscale materials is the most relevant consideration for defining the small business exemption for the rule, because many nanoscale chemical substances manufactured or processed in small volumes.  For the same reason, EPA would not consider it relevant to consider only nanoscale chemical substance sales or a different sales figure for a processor to identify what is considered a small processor exempt from the rule.  
Comment 51:   One commenters stated that the definition of small manufacturer or processor should be consistent with the Small Business Administration (SBA) definitions based upon its analysis of sectors impacted, sales and employment.
Response:  EPA consulted with the SBA on factors to be included in the definition.  SBA's response is included in the docket.  The only suggestion from SBA was to increase the sales figure based on inflation to a higher number around $9.5 million. As discussed in Comment 49, EPA chose a figure of $11 million in the final rule.  The other considerations of sustainability, sectors impacted, and employment do not greatly affect whether a company is considered a small manufacturer or processor because they do not have measurable impact on the total sales of a company.    
Comment 52:  Several commenters stated that EPA has underestimated the number of affected entities and the number of discrete forms of nanoscale materials that individual companies may have to report and the burden associated with that reporting.  One commenter stated that in the references cited by EPA in its economic analysis "There is no mention of large scale additives or legacy products of any kind. In particular, there is no mention of color pigments" and "EPA's description and estimate of the size of the regulated community indicates that EPA could not possibly have intended to include millions of pounds of color pigments or the thousands of companies which manufacture and use color pigments in inks, paints, plastics, ceramics, cement and other industries."  Another commenter stated that "...members have anecdotally mentioned that they may have dozens or more potentially reportable discrete forms of nanoscale substances, not the approximately 5 per company estimate in the EPA's economic analysis of the Proposed Rule.  A commenter also stated that the data used to develop EPA's estimates of number of affected entities is outdated. Commenters stated cost estimates should be adjusted based on these considerations and the broad scope of the rule.  
Response:  EPA's analysis for the proposed rule evaluated several sources of data to estimate the number of companies affected by the rule, including BCC Research's report: Nanotechnology: A Realistic Market Assessment (2008). Since the proposal, BCC released an updated report (2014) which EPA used to recalculate its estimate for the number of nanoscale material companies following the same methodology as in the proposal. EPA found that there was no significant difference in the estimated number of nanoscale material firms using the updated information (there was actually a slight decline) and therefore, finds its estimate of nanoscale material firms to be a reasonable estimate of those affected by the rule. Previous comments clarifying the definition of a reportable chemical substance, trace amounts, and that every use of a formulation would not require separate reporting should make it clear that reporting of every legacy product such as color pigments would not be required, and EPA expects that reporting would be required for very few. EPA recently reviewed premanufacturing notices (PMNs) for pigments and dyes submitted to the Agency for fiscal years 2014, 2015, and 2016 (fiscal year 2016 ended May 31, 2016) and found that of the 179 PMNs submitted, 70 submitted information on particle size (particle size is not required to be reported). Of those 70, only 1 pigment/dye would be of a size (<100 nm) that would be reportable under this rule, although it is not known if that pigment/dye would have met all other criteria which would make it subject to reporting. Commenters provided no additional data or specific references which EPA could use to further assess the likelihood or number of pigments requiring reporting.
EPA disagrees with those commenters who argue that EPA's estimate of the number of reportable nanoscale materials per firm are underestimated, providing no more than an anecdotal mention that companies may have more reportable nanoscale substances ("may have dozens or more") than estimated by EPA, stating that companies had an uncertain understanding of the proposed definition of discrete forms. EPA has provided more clarification on definitions (e.g., responses to comments 10, 11, 12) to address uncertainty in what is a reportable substance. EPA's estimate of number of reportable nanoscale materials represents an average across firms, therefore, any particular firm may have fewer or more materials that it must report. Because the information is anecdotal, it is not clear what the basis of the commenter's estimate is. EPA's estimate reflects an annual number of reportable nanoscale materials per year and includes consideration that at any one time, a firm may have a number of nanoscale materials that may be in various stages of development, including R&D and commercially relevant materials. Because the rule provides an exemption for nanoscale materials being used for R&D, these are not included in EPA's estimate of reportable substances. It is not clear if the commenter's anecdotal information excludes these materials. EPA's estimate of number of reportable nanoscale materials represents an average across firms, therefore, any particular firm may have fewer or more materials that it must report. Furthermore, to evaluate the effect of different estimates of the number of reportable substances per company, EPA has also developed a sensitivity analysis which evaluated a range of reportable substances per firm during the first year from .39 (implying fewer than one nanoscale material per year over the time frame of the analysis) to 25.67 which is included in the economic analysis. Commenters did not provide specific references or data that would allow EPA to further revise its analysis on the basis of the number of reportable nanoscale materials.
Comment 54:  A commenter stated that EPA lacked quantitative data for its regulatory flexibility analysis finding for processors, and should identify data for processors and conduct an economic analysis using that data.  The commenter also stated that "Small businesses have expressed concerns that some processors may not have the regulatory sophistication or personnel to comply with the reporting requirements. As a result, these small businesses will incur the cost of third party training and other professional assistance. Such additional costs are not included in the agency's EA. In addition, the agency has not considered other important cost factors in the EA such as the time and effort required to acquire, review and analyze the relevant information to determine whether a material meets the reportable criteria and whether or not a reporting obligation exists. In many cases, processors may not have the information and have to take additional steps to obtain the information from their suppliers or manufacturers. This may prove to be particularly burdensome for small processors with limited resources."  Based on this EPA should recognize the different, potentially higher administrative costs for processors and conduct an economic analysis on that basis.    
Response: Notwithstanding this comment, EPA believes that the reporting burden per reportable substance is the same for all entities reporting under the rule and does not include different burden estimates for manufacturers and processors. The information required by this rule must only be reported if it is known to or reasonably ascertainable by persons subject to the rule. This is defined to mean all information in a person's possession or control, plus all information that a reasonable person similarly situated might be expected to possess, control, know, or obtain (the rule does not require companies to develop information). 
EPA's estimate of burden does include an estimate for completing all required information elements. For some companies reporting on certain materials, it is possible some information fields may not be known or reasonably ascertainable so that EPA's estimate may overestimate the costs for some reports. Furthermore, EPA does not expect that a processor would need to incur third party training or other professional assistance in order to provide reasonably known or ascertainable information. What constitutes known or reasonably ascertainable may differ across business types and sizes such that what may be reasonably ascertainable for one business, for instance, a large manufacturer with more available resources, may not be the same for another business, such as a small processor with limited resources. Regardless, EPA has provided an exemption from the rule for the smallest businesses involved with manufacturing and processing nanoscale materials (those with less than $11 million is sales) who may have more limited resources.
Not only are companies required to report only that information which is known or reasonably ascertainable, but companies, including processors, need only use information that is in their possession or which is reasonably ascertainable to determine their compliance obligations under the rule. Therefore, processors and are not expected to incur a significant burden for compliance determination. 

Comment 55:   One commenter stated that "EPA should apply its annual growth rate methodology to its estimate of the regulated community (described in section 2.2.4 of the EA) and recalculate subsequent analyses based on this consideration to more accurately reflect industry growth over time. Assuming EPA adopts the recommendation to apply the annual industry growth rate methodology used in its sensitivity analysis to its broader EA, EPA should amend its calculations to reflect the correct denominator (number of years). This recalculation would increase the total number of firms impacted by this rulemaking, including, potentially, the number of small firms affected.
Response:  In EPA's original analysis, it assumed no growth in the number of regulated entities over time, however, provided a sensitivity analysis incorporating a growth rate to evaluate the effect of an increased number of firms subject to reporting over the time frame of the rule. The commenter suggests that EPA incorporate this growth rate in its main analysis and make a correction to the estimated growth rate based on a revised calculation.  To determine whether to incorporate the growth rate into the main analysis, EPA reviewed the estimated number of firms manufacturing nanoscale materials and subject to the rule in its original analysis and compared it to an estimate using more recent data to evaluate the growth in the industry. EPA's original analysis relied primarily on a 2008 market study to estimate the number of U.S. nanoscale material manufacturers subject to the rule. EPA reviewed a 2014 version of the same study and, following the same methodology, found little change (actually a slight decrease) in the number of estimated nanoscale material manufacturing companies in the U.S. that would be subject to the rule, supporting EPA's assumption of no growth in the overall number of nanoscale material firms.
EPA did, however, revise the growth rate in its sensitivity analysis to correct for an error identified by the commenter.
Comment 56:   Several commenters suggested that EPA should better define particle.   
One commenter stated "The word "particle" is not a term with specific meaning. It is critical that EPA is clear about the definition of "particle" so that companies understand what materials require reporting. For example, does the term "particle" include solid objects that contain internal crystalline domains at the nanoscale? Does it include dispersions, suspensions, or aerosols? A definition of "particle" would provide an important starting point for determining whether a material is subject to reporting. It should take into account the ability of a "particle" to move freely in its environment."
Response:  EPA will use the definition of particle from ISO which is a "minute piece of matter with defined physical boundaries."   The notes to the ISO definition may assist in applying this definition. Note 1: A physical boundary can also be described as an interface. Note 2: A particle can move as a unit.  EPA is using this definition because there is international agreement on the definition and it addresses the commenter's questions about the ability of a particle to move in the environment and that it could include dispersions, suspensions, or aerosols. 
Comment 57:   Because the preamble to the rule stated that a reportable chemical substance contained particles 1-100 nm in at least one dimension but the proposed regulation did not specify the number of dimensions, several commenters suggested that EPA clarify the number of dimensions for particles of 1-100 nm that are required for nanomaterial to be a reportable chemical substance. 
Response: Chemical substances that contain particles that are 1-100 nm in at least one dimension are considered reportable chemical substance.  EPA has changed the definition of reportable chemical substance in the final rule to state that particles must 1-100 nm in at least one dimension. 
Comment 58:  Several commenters asked for clarification of the criterion to exclude chemical substances that dissociate completely in water to form ions that are smaller than 1 nm.  The commenters asked how fast or what the rate of dissociation would be. 
Response:  The rate of dissociation or how fast that dissociation occurs does not affect which chemicals are excluded.  If the chemical substance completely dissociates to form ions smaller than 1 nm it is not a reportable chemical substance.  
Comment 59:  Several commenters stated that the shape criteria for identifying reportable chemical substances are too vague and unworkable.  The commenters asked what the criteria are to discern one shape from another. For example one commenter stated  "For morphology, how would manufacturers and processors distinguish between the different morphologies identified in the proposed regulatory text: what definitions would distinguish for example a rod from an ellipsoid, needle, wire, and/or fiber as these shapes could be considered on a continuum?  Another commenter stated "It is unclear how different the shapes of two forms would have to be in order to trigger the discrete forms requirement." 
Response:  As noted in the proposed rule the different morphology could be any change in the shape of particles.  Different morphology does not include random shape changes or natural variation in shapes of particles that are not definitive and that, as commenters have noted, occur in a continuum.  Some nanoscale materials are engineered to give all the particles a certain morphology or shape.  The change in shape needs to be a specifically engineered change in the shape of particles of a nanoscale material, to effect a change and form a unique or novel property for a chemical substance in the particle size range of 1-100 nm.
Comment 60:  Several commenters stated that the definition of discrete forms of a reportable chemical substance needed to be clarified, including factors to be used to distinguish discrete forms.  One commenter stated the factors should be eliminated from the rule as they are unnecessarily burdensome, while other commenters suggested deleting some of the elements such as zeta potential, dispersion stability, and surface reactivity.  The commenters believe that the proposed elements for reporting discrete forms "cannot reliably be measured" and that the rule "compels companies to conduct tests on these or other physical-chemical properties to determine whether they must report, many of which are not required or commonly performed."   
Response:  To clarify the definition of discrete forms of a reportable chemical substance and address these comments, EPA will include responses previously made to several other comments.  EPA cannot require testing under a TSCA section 8(a) rule.  While manufacturers and processors are not required to test for the properties identified in the definition of discrete forms of a reportable chemical substance, they are still required to determine their compliance obligations under the rule based upon information that is in their possession or which is reasonably ascertainable. If information within a company's possession or that is reasonably ascertainable does not demonstrate that the company is manufacturing or processing a discrete form of a reportable chemical substance, there is no obligation to report.  EPA expects that in most cases such information will be in the company's possession or reasonably ascertainable.  For example, persons subject to the rule may be required to report when they change a manufacturing process to make a different size material in the range of 1-100 nm.  However, they are not required to report that different size material if particle size and surface area of the nanoscale material have not sufficiently changed to meet the definition of a discrete form of a reportable chemical substance.  
Comment 61:  Several commenters asked whether research and development is exempt from reporting or asked EPA to clarify the exemption.  One commenter asked EPA to define small quantities. Others asked EPA if companies could sell research and development quantities for profit or if reporting was required if the core commercial activity of a company was research and development.
Response.  As described in 40 CFR part 704.5(e), a person who manufactures (includes import), processes, or proposes to manufacture or process a substance subject to reporting under this rule only in small quantities solely for research and development is exempt from the reporting requirements of the rule.  Small quantities solely for research and development  (or ``small quantities solely for purposes of scientific experimentation or analysis or chemical research on, or analysis of, such substance or another substance, including such research or analysis for the development of a product'') is defined in 40 CFR part 704.3 to mean quantities of a chemical substance manufactured or processed or proposed to be manufactured or processed solely for research and development that are not greater than reasonably necessary for such purposes. This exemption applies if a company sells research and development quantities for a profit or if the main commercial activity of the company is research and development. 
Comment 62:  A commenter asked what mechanism will be used to update any new information if there is a change in manufacture, processing or use becomes necessary after the first reporting of a discrete form. 
Response: Because this rule only requires one time reporting, updating with new information is not required unless a manufacturer or processor is reporting a new discrete form of a reportable chemical substance.  
Comment 63:  Several commenters asked EPA to clarify reporting requirements for reportable chemical substances that are contained in coatings and mixtures.  One commenter asked EPA to define coating.  One commenter stated it is not clear why coated nanomaterials are defined separately from chemical mixtures.  The commenter stated there are cases where discrete nanomaterials are surface treated (commonly coated with polymeric substances) in a similar fashion as defined for chemical mixtures.  Another commenter stated their seemed to be a different standard for reporting on mixtures and that EPA needed to explain why this information was necessary.
Response:    Mixtures are not reportable under this rule; however the components of any mixture that contains reportable chemical substances subject to the rule would be reported.  The term coating in the rule describes surface treating or coating of a reportable chemical substance with another chemical substance.  The change in coating makes it a discrete form of a reportable chemical substance subject to reporting even if all of the other intrinsic characteristics of the reportable chemical substance remain the same.  Coating or surface treating a nanoscale material results in a nanoscale material with different properties. There is not a requirement that every chemical substance coated or surface treated with another chemical substance must be reported.  However, any type of engineering including surface treatment of a chemical substance that results in a reportable chemical substance requires reporting under this rule. 
Comment 64:  Commenters stated that EPA should clarify that the exemptions for new chemicals reported since January 1, 2005 and the NMSP would not exempt information that has changed since the original reporting.
Response: For a reportable chemical substance that was submitted as a new chemical substance under section 5 of TSCA or as part of the NMSP, no updated information would need to be reported unless a manufacturing or processing change resulted in a new discrete form of the reportable chemical substance.   
Comment 65: Several commenters asked EPA to clarify and confirm that articles are exempt.  Commenters asked if the article exemption would apply to textile yarns, fabrics, apparel, nanometal metalized yarns, and extremely large and complex equipment. One commenter supported the article exemption.  
Response:   As described in 40 CFR 704.5(a), a person who imports, processes, or proposes to import or process a reportable chemical substance subject to this rule solely as part of an article is exempt from the reporting requirements of this part with regard to that substance.  Manufacturers (including importers) or processors of a reportable chemical substance that is incorporated into an article would be required to report any required information for activities before the chemical substance is incorporated into the article.  An article is defined in 40 CFR 704.3 as manufactured item (1) which is formed to a specific shape or design during manufacture, (2) which has end use function(s) dependent in whole or in part upon its shape or design during end use, and (3) which has either no change of chemical composition during its end use or only those changes of composition which have no commercial purpose separate from that of the article, and that result from a chemical reaction that occurs upon end use of other chemical substances, mixtures, or articles; except that fluids and particles are not considered articles regardless of shape or design.  The article exemption would usually apply to the products cited by commenters. Any person who is not sure if their product meets the definition of an article under TSCA should contact EPA for clarification.
Comment 66:  Commenters stated that aggregates and agglomerates are not adequately defined. One commenter asked if there was any threshold of energy for dispersion of aggregates and agglomerates.    
Response:  There is no threshold of energy dispersion for aggregates and agglomerates.  Aggregates and agglomerate are defined using the definition from ISO to clarify the types of particles that can be used to measure particle sizes, for purposes of determining if a chemical substance is a reportable chemical substance subject to the rule.  Primary particles are also identified for this purpose.
Comment 67:  Commenters asked for further clarification on emulsions and micro emulsions and if they should be specifically included or excluded within the definition of a reportable chemical substance.  
Response:  Emulsions and micro emulsions per se are not reportable chemical substances.  If a chemical substance contained in an emulsion meets the definition of a reportable chemical substance then that chemical substance is subject to the requirements of the rule. One example cited by a commenter where a chemical substance had only incidental amounts of particles are less than 100 nanometers and no size-dependent properties are being exploited would not be a reportable chemical substance.  
Comment 68: Commenters asked EPA to clarify that chemical substances used for miniaturization through creation of nanostructures, and chemical substance used in nanoscale manufacturing are not covered by this rule.
Response:  If the chemical substances described by the commenter meet the definition of a reportable chemical substance they would be subject to reporting requirements of the rule.  Whether a chemical substance is used in nanoscale manufacturing or miniaturization through creation of nanostructures are not criteria of a reportable chemical substance. 
Comment 69:  A commenter asked that EPA allow reporting of multiple nanoscale forms of reportable chemical substances in a single submission with appropriate identification of their range in material properties.  The commenter stated this would be more consistent with current new chemicals reporting and should also assist with data management. 
Response:  Required reporting may be consolidated under the rule.  Companies should consult with EPA before submitting consolidated reports.  EPA will issue guidance on consolidated reporting on its website. 
Comment 70:  A commenter stated that crystallinity should be included in the reporting requirements.  
Response: Crystallinity is already included in the physical and chemical properties worksheet for nanoscale materials specific data.
Comment 71:   Numerous commenters supported electronic reporting, although one commenter supported only if it was fully functional.  One commenter stated electronic reporting should be voluntary.  Other commenters noted the electronic reporting will not necessarily reduce the reporting burden if it is not functional or for those persons who will be submitting a limited number of reports. 
Response.  Even with the exceptions noted by commenters, overall electronic reporting remains the least burdensome approach, based upon EPA's extensive experience with electronic reporting for PMNs and other submissions.  EPA will assist persons subject to the rule with issues regarding first time reporting or electronic reporting. 
Comment 72: EPA specifically asked for comments on a future rulemaking for periodic reporting on nanoscale materials in commerce. Numerous commenters did not support future rulemaking for periodic reporting of nanoscale materials while another group of commenters did support future periodic reporting requirements.  Several commenters stated that it depended on certain conditions such as limiting to manufacturers, no 135-day period, and the reporting threshold. 
Response: EPA will take these comments into consideration regarding any future rulemaking proposal. 
Comment 73:  Commenters generally supported making data available to the public, including reporting of aggregated information, integrating data with existing databases, including worker exposure data, issuing for notice and comment each risk evaluation the agency conducts for chemical substances reported under the rule, and making as much data public as possible including limiting CBI claims. One commenter objected to using Chemview as it would just generate a list of chemical substances/defacto Inventory with a negative connotation.  The commenter asked if EPA would distinguish between different forms of the same chemical substance.  
Response:  EPA will take these comments into consideration when making reported information available to the public.  EPA will make as much information publicly available as is feasible, including different forms of the same chemical substance.  How EPA presents that information will depend on the information submitted and what is claimed as confidential. 
Comment 74:  A commenter stated that persons subject to the rule should be required to report weight percentage of impurities and byproducts and should also be required to report the chemical identity and particle size information.
Response:  Chemical identity, particle size information, and weight percentage of impurities are already part of the reporting requirements. 
Comment 75:  Several commenters did not support the exemption for reportable chemical substances already reported under section 5 of TSCA.  Commenters thought that additional reporting of new information not previously reported would be an opportunity to update production and use information.  
Response:  EPA continues to get updated data because of testing requirements and significant new use notices for new chemical submissions that are nanoscale materials that have been regulated under section 5 of TSCA. Under the 8(a) rule EPA will get reporting from manufacturers or processors who did not report the nanoscale material under section 5 of TSCA.  EPA is including the exemption to avoid duplicate reporting. 
Comment 76:  Two commenters identified the three factors used to determine discrete forms of a reportable chemical substance which are changes in process, size, and certain physical properties for identifying a discrete form of a reportable chemical substance.  The commenter proposed that a change in any one of those factors instead of all three factors should require reporting of a discrete form of a chemical substance.  One commenter stated this was because a change in any one of these factors, "can independently affect the risk potential associated with exposure to the substance and hence should trigger separate reporting."
Response:  Not all process changes result in significant changes in properties.  Changing to just one of those factors to require reporting would not allow for the natural variability of size and properties of nanoscale materials.  EPA will retain the approach of needing all three factors to change. 
Comment 77:  One commenter stated that "release information" should specify that such information should include any potential unintended releases into the environment such as spills, fires, etc.
Response:  Persons subject to the reporting requirements of the rule are already required to report environmental releases from routine or repeated activity or even non-routine releases that are known or reasonably ascertainable.  However releases due to true emergency conditions such as a fire or a catastrophic spill would not be reportable as that information is not reasonably ascertainable and would be too speculative.
Comment 78:  The definition of zeta potential appears incorrect in the proposed rule document, and clarity is required to ensure the appropriate parameters are reported.  The commenter stated that "Zeta potential is not equivalent to the net surface charge on a particle, but rather an estimation of that property.  The zeta potential or electrokinetic potential of a particle is the electrical potential of the particle's interfacial double layer at the slip plane and is measured in milliVolts."
Response:  EPA agrees that the definition should be clarified.  EPA will use a broader description of zeta potential.  Zeta potential is the electrostatic potential near the particle surface.  It can be measured using various methods.  See ISO/TR 13014:2012 "Guidance on Physicochemical Characterization for Manufactured Nano-objects Submitted for Toxicological Testing" (Ref. 4) and the description of zeta potential by Colloidal Dynamics (Ref. 5) for examples.  It is typically measured by electrophoresis.
Comment 79:  A commenter noted that the adverse effects cited refer to several articles wherein the observed effects have been later attributed to residual solvent and inappropriate experimental procedures.  
Response: While some scientific information has changed for some of the articles referenced as noted by the commenter, the scientific information in the other references in the proposed rule and subsequent data that has been developed do demonstrate that some nanoscale materials may have different properties regarding environmental health and safety. 
Comment 80:  One commenter stated the rule should include pesticides while other commenters stated that the rule should not apply to any food, food additive, drug, cosmetic, medical device, pesticide or other excluded material."
Response:  As stated in the preamble to the proposed rule, a chemical substance as defined under TSCA section 3(2) does not include any food, food additive, drug, cosmetic, medical device, pesticide or other excluded materials. This rule does not apply to those enumerated items because there is no jurisdiction under TSCA to do so.
Comment 81:  A commenter asked what the criteria are for distinguishing new processing methods for a nanoscale material from existing methods.  The commenter asked if EPA will provide guidance or regulatory citations as to what would constitute a process change that would require filing a new report. 
Response:   The type of process change is not the criterion, it is the intent of the process change.  Any manufacturing or processing change that is intended to change particle size and properties would be a process change that could require new reporting. 
Comment 82: Two commenters stated that 22,000 pounds was still too large for a reporting threshold and was not justified. 
Response:  The commenters are referring to the 22,000 pound production volume number cited in the preamble of the proposed rule for premanufacture notices that were submitted for nanoscale materials. EPA used that data to justify changing the small business exemption for this rule. 22,000 pounds is not a reporting threshold in the final or proposed rule.  There is no quantitative reporting threshold. 
Comment 83: Commenters stated that EPA should give more explanation on what it plans to do with data.
Response: EPA intends to use the information to improve its assessment of nanoscale new chemical substances.  EPA will also review the information to determine if there are potential risks that warrant risk management action.  EPA will also make any non-confidential information available to the public.  Until EPA receives and reviews the data it is unable to give a more detailed explanation of what it will do with the data. 
Comment 84:  A commenter stated the definition proposed for a discrete form needs to reflect the preamble discussion that a change in both size and property is required, if this becomes part of the final rule.
Response:  The definition in section 704.20(a) of the rule states that process, size, and property must change to be considered a discrete form of a reportable chemical substance. EPA has clarified the definition in a manner that reflect this.
Comment 85: A commenter noted that the preamble in the proposed rule stated that a change in mean particle size of 10% or greater would be used to determine if a discrete form of a reportable chemical substance differs from another form of the same reportable chemical substance.  However, the proposed regulatory text used 7 times the standard deviation of the measured value (+/- 7 times the standard deviation) for the change in mean particle size.  The commenter asked EPA to clarify what was intended. 
Response: In the proposed rule, the preamble inadvertently stated a change in mean particle size of 10% or greater.  The proposed regulatory text used the 7 times the standard deviation of the measured values (+/- 7 times the standard deviation) for change in mean particle size.  The 7 times the standard deviation language is what was intended and is contained in the final rule.   
Comment 86:  Commenters made numerous suggestions that fall outside the scope of the rule.  This included a future rule to define all nanosized chemical substances as new chemical substances, reconsider promulgating the significant new use rule for nanomaterials, consider a test rule and TSCA section 6 rule for nanomaterials, fully implement and fund TSCA, limit CBI claims, explain how the requirements of the rule would inform safety-by-design principles, and work with stakeholders to develop an international definition of nanomaterial. 
Response:  Because these comments fall outside the scope of the rule, EPA is not responding to these comments. EPA may consider future measures based on submitted information
Comment 87: A commenter asked that EPA clarify that the film exemption includes polymer coatings that are not in the 1-100 nm range.
Response:  If a polymer coating is not in the 1-100 nm range, it is not a reportable chemical substance.
Comment 88: One commenter believes that the exemption for "ions" could be extended to any material which fully dissociates or dissolves in water, regardless of size or degree of ionization, as these materials will be equivalent to the molecular form in relevant environmental conditions or during human exposures.
Response: EPA is not expanding the exemption as some nanoscale materials that do dissociate or dissolve in water exhibit unique or novel properties. 
Comment 89:  One commenter stated "If the nanoscale material is fixed to non-nanoscale materials and doesn't act as nanoscale material, it should be exempted from the scope of this proposed rule because in such a case exposure will be very small." 
Response:   If the nanoscale material is a reportable chemical substance then reporting would still be required if it was "fixed" to a non-nanoscale material.  EPA does not have enough information on these types of materials to establish that exposures are small and exempt all of them from reporting.   
Comment 90:  A commenter stated that "applications which result in low or no significant pulmonary exposures to isolated nanoscale chemical substances should be exempt."
Response: EPA does not have sufficient information to identify the applications or exposures that would be the basis for an exemption. Therefore the Agency is not including such an exemption.
Comment 91: EPA should clarify whether a final product made from a reportable chemical substance that will be a solid article of non-nano scale such as a coated electrode or a centimeter size crystal is subject to reporting. 
Response:  If the final product meets the definition of an article at 40 CFR 704.5(a), it is exempt from reporting.  If a final product does not meet the definition of a reportable chemical substance, it is not subject to reporting even if it was made using reportable chemical substances. 
Comment 92: A commenter suggested that EPA exempt heavy fuel oils from reporting because they are not manufactured to be 1-100 nm but some do fall within that size range.   
Response:  Heavy fuel oils would not require reporting as they are not solid chemical substances and do not exhibit unique and novel properties because of their size.  By definition a heavy fuel oil is manufactured to be burned for energy.  That intrinsic property will not change because of a change in particle size. 
Comment 93: A commenter noted there was no analysis of the impact of the 135-day notification period, "Both in terms of sending a negative signal to the market and not allowing companies to respond quickly to customer requests."  Commenters stated cost estimates should be adjusted to consider potential profit losses due to the delay in market introduction.
Response: EPA's responses to comments 42 and 43 have addressed that the 135 day period to report a discrete form of a reportable chemical substance is only a notification program and does not affect commercialization of existing chemical substances. Therefore, companies will not experience delay in market introduction and potential profit losses as a result of this rule.
Comment 94: One commenter requested that the benefits to POTWs be included in the economic analysis. They note that "Active EPA management of nanoscale materials will ensure that the chance of costly incidents of wastewater treatment interference or restrictions on biosolids disposal will be reduced."
Response: The rule requires reporting on nanoscale materials only and does not assume that there are risks related to these chemicals, nor does the proposed rule manage any potential risks associated with nanoscale materials. Therefore, it is not appropriate to include any benefits for managing nanoscale materials in the benefits described in the Economic Analysis.

References from the Final Rule
 EPA. Chemical Substances When Manufactured or Processed as Nanoscale Materials; TSCA Reporting and Recordkeeping Requirements; Proposed Rule. Federal Register April 6, 2015 (80 FR 18330) (FRL-9920-90).
 2016. EPA. Response to Comments to the Proposed Rule, Chemical Substances When Manufactured or Processed as Nanoscale Materials; TSCA Reporting and Recordkeeping Requirements; RIN 2070-AJ54. Docket # EPA-HQ-OPPT-2010-0572.
 2011. Executive Office of the President. Policy Principles for the U.S. Decision-Making Concerning Regulation and Oversight of Applications of Nanotechnology and Nanomaterials. https://www.whitehouse.gov/sites/default/files/omb/inforeg/for-agencies/nanotechnology-regulation-and-oversight-principles.pdf
 2015.  EPA. Economic Analysis for the TSCA Section 8(a) Reporting      Requirements for Certain Nanoscale Materials (RIN 2070-AJ54). xxxx xx, 2016.
 2012. International Organization for Standardization (ISO). Nanotechnologies -- Guidance on Physicochemical Characterization for Manufactured Nano-objects Submitted for Toxicological Testing. ISO/TR (Technical Report) ISO/TR 13014:2012.
 1999. Colloidal Dynamics. The Zeta Potential.  http://www.colloidal-dynamics.com/docs/CDElTut1.pdf.
 2013. ISO/TR. Guidelines for Characterization of Dispersion Stability. ISO/TR 13097:2013.
 2016. EPA. Information Submission Form. TSCA section 8(a) Information Reporting for Nanoscale Materials. EPA Form No. 7710 - [tbd]; EPA ICR No. 2517.02; OMB Control No. 2070 - NEW. 
 2013. EPA. Electronic Reporting Under the Toxic Substances Control Act; Final Rule. Federal Register (78 FR 72818, December 4, 2013) (FRL 9394-6).
 2007. EPA. Nanoscale Materials Stewardship Program  -  Concept Paper.
 OSHA. OSHA Hazard Communication Standard; 29 CFR part 1910.1200, 
https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=standards&p_id=10099.
 2009. EPA. Interim Report on the Nanoscale Materials Stewardship Program. 
 20##. EPA. Chemical-Specific Rules, Toxic Substances Control Act Section 8(a).  OMB control No. 2070-0067 (EPA ICR No. 1198.##).
 2015. EPA. Addendum to an Existing EPA ICR Entitled: Chemical-Specific Rules, Toxic Substances Control Act Section 8(a).  EPA ICR No. 2157.02; OMB Control No. 2070-[new].