Document ID: EPA-HQ-OAR-2021-0133-0009
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2022-03-07T05:00Z

﻿                  UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
           SECTOR POLICIES AND PROGRAMS DIVISION
           OFFICE OF AIR QUALITY PLANNING AND STANDARDS
           OFFICE OF AIR AND RADIATION

DATE:January 8, 2021 

SUBJECT:Documentation of Phone Conference with Nisus Corporation

FROM:John Bradfield (EPA/OAR/OAQPS/SPPD/NRG)

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TO:EPA-HQ-OAR-2021-0133
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The purpose of this memorandum is to discuss the phone conference between John Bradfield of the U.S. Environmental Protection Agency (EPA) with Greg Baumann and Anna Crowder of Nisus Corporation on December 8, 2020 regarding manufactured preservatives for use in the wood preserving process. This information will be used in the technology review for the National Emission Standards for Hazardous Air Pollutants for Wood Preserving Area Sources (Subpart QQQQQQ).  

I.  New Preservative Technology

Q1. What new preservatives and/or active ingredients have been introduced into the wood preserving industry since 2007? What products are they used on? What are the relative costs for new/old preservatives?

Nisus is new to Copper Naphthenate. Nisus registered its Copper Naphthenate product in 2011. Prior to that, Nisus had focused exclusively on Borate products. Copper Naphthenate is not a new product, of course.  It was identified as a preservative in the 19th century, began to be manufactured commercially in the 1920's in Europe, and in the 1950's in the U.S. Nisus entered the Copper Naphtenate market for several reasons. The only manufacturer was planning to end production; as a large company, a small market product like Copper Naphthenate did not match up well with their business model. EPA encouraged Nisus to take on the product since it was the only general wood preservative available to consumers. As a small company, a small market product like Copper Naphthenate was easy for Nisus to take on. Since the process had the EPA's attention, the registration proceeded quickly.  Nisus is the major producer of Copper Naphthenate; there are no other current U.S. producers that they are aware of.

Another preservative product that Nisus has registered is Oxine Copper (Copper-8-Quinolinolate).  It is already widely used as a sap stain and is AWPA listed for treating mold, fungi and termites in above ground wood applications. Unlike the green tinted products, Oxine Copper imparts a nice, golden color to the wood, a potential marketing plus. It's not one of our products but another relatively new product is DCOI, sometimes referred to as DCOIT. 

Q2. Are there new preservatives and/or active ingredients currently being evaluated/registered under FIFRA? If yes, what types?

We are not aware of any new active ingredients under consideration. The wood preservation industry doesn't develop new pesticides, it's too expensive generally. In the past new treatments have been developed based on products developed by the agriculture or biocide pesticide industry, which has the market and capital for pesticide development.  

Q3. Is it easier/cheaper to control HAP emissions from wood preservatives through P2 (material/ingredient substitution) or add-on controls?

Nisus doesn't own any plants that treat wood. Nisus does not get involved in any plant pollution control processes except to help customers. Regarding preservation treatment use at the facility, Nisus provides information on product dilution rates based on the label. 

Q4. Are there any "greener" alternatives to creosote?  What are the technical issues for railroad ties/switches and/or utility poles?

Copper Naphthenate can be considered a greener alternative to creosote in several ways. Copper Naphthenate is a general use, not a restricted use, pesticide; it is safe enough to be purchased and used by consumers.  Only Copper Naphthenate and DCOI are general use pesticides. All other pesticides can only be sold commercially to treatment facilities and used by state certified applicators.  Consumers can't purchase restricted use pesticides without a state license.  Copper Naphthenate does not contain any Hazardous Air Pollutants of concern. One technical advantage is that railroad ties that have Copper Naphthenate in them don't drip in place like creosote can. Consequently, some railroads prefer Copper Naphthenate for bridge ties. Copper Naphthenate's environmental footprint is relatively good. Borate pretreatment for ties is also perceived to be a green treatment and enhances product lifetimes. About 90% of railroad ties are creosote but there is steady growth in the Copper Naphthenate market.

The use of Copper Naphthenate in utility poles is small but growing. Because of its environmental impact, some utilities have used Copper Naphthenate nearly exclusively for years. Copper Naphthenate and CCA have the technical advantage of not dripping. Both pentachlorophenol and creosote can drip and be messy at the base of a pole. Copper Naphthenate and CCA are also less conductive than pentachlorophenol and creosote poles. Climbing Copper Naphthenate poles is not an issue while CCA poles need a secondary treatment to improve its climbing characteristics. Pentachlorophenol is the main product used for utility poles, followed by CCA. Creosote and Copper Naphthenate have a small part of the utility pole market. The announcement that pentachlorophenol production would be ending means that the utility pole market will be changing. 

Q5. How are companies reducing HAP emissions from creosote?  We noted permits with specific naphthalene content (mass fraction, by weight) limits for incoming materials and total facility emission limits for naphthalene, POM, biphenyl, dibenzofuran, and quinoline.

Nisus is not in the creosote business and does not have any information on this subject. 

Q6. We also noted some facilities using add-on controls (e.g., condenser/ scrubber systems) to reduce HAP/VOC emissions from creosote operations.  Are there new (since 2007) creosote mixtures or solutions being used today?  What was the motivation  -  odor issues?

Nisus is not in the creosote business and does not have any information on this subject. 

Q7. Are there any HAP issues/concerns with fire retardants?  Most seem to be borates and contain no HAP.

No. Nisus markets a zinc borate to be used in wood products as a pesticide, generally not as a fire retardant. Zinc borate has no HAP, but because of the zinc, requires workplace protection to avoid breathing dust containing zinc borate. 

Q8. What Nisus products can meet which AWPA standards? (AWPA U1, UC3B, UC4A, UC4B, UC4C, 5A, 5B, 5CU1, UC3BU1, UC3BU1, UC3B
Copper Naphthenate:  UC3A, UC3B, UC4A, UC4B, UC4C 
ZB (Zinc Borate): UC1, UC2 and UC3A 
Copper 8-quinolinolate:  UC1, UC2, UC3A and UC3B
SBX (water soluble borates):  UC1, UC2 
SBX is also permitted as a dual-treatment for crossties when followed up with an over-treatment of Creosote or Copper naphthenate  -  this would be UC4A, UC4B and UC4C.

II.  Existing Preservative Technology

Q1. Pentachlorophenol (PCP or Penta) is still used for some utility poles and other outdoor/commercial applications. It typically has some associated HAP (dioxin) emissions from impurities  -  permits show some facilities have switched, but not all  -  is the industry waiting to see if another manufacturer steps in?  Are impurity levels better today than pre-2007? (

Nisus is not in the pentachlorophenol business.  However, because of the pentachlorophenol ban under the Stockholm convention, Canada is proposing cancelling its registration and many pentachlorophenol users are switching to Copper Naphthenate. Changeover requires cleaning and produces hazardous waste with unused penta. Also, some equipment metals, primarily in pumps, may not be compatible with Copper Naphthenate, and require a relatively easy changeout. 

Q2. CCA was discontinued for residential/household use in 2003 but is still used for outdoor/commercial applications. It was typically replaced with ACQ or CA (which contain no HAP)  -  permits show several facilities have switched, but not all  -  why not? 

Nisus is not in the CCA, Ammoniacal Copper Quaternary or Copper Azole business and does not have any information on this subject. 

Q3. Some permit application changes mentioned industry concerns about a possible "quat" shortage and switching from ACQ to CA products.  Was that a real issue/concern? (Relevant to Nisus?)

Nisus is not in the Ammoniacal Copper Quaternary business but understands that there is a Quaternary shortage because of its use as a disinfectant and the Covid pandemic.  Quaternary comes from China and has a tariff. 

Q4. Nisus indicates in their corporate history that Copper Naphthenate was added to the product list when other preservative manufacturers were exiting the market for the product and a lapse in the EPA registration was possible. Why had the preservative fallen out of favor? 

As noted above, Nisus was encouraged by EPA to keep Copper Naphthenate available. EPA expedited the registration process. 

Q5. Is Nisus aware of any companies using add on controls (e.g. scrubbers, etc) to control odors or emissions associated with Copper Naphthenate application (see Q6 regarding creosote above)?

No.  Copper Naphthenate does have odor in concentrated form, but after it is diluted, usually by a factor of 8 or more, the odor is diminished. 

Q6. There are reports of odors from Copper Naphthenate products.  What are the causes of the odors?  Is there a standard practice to reduce odors? 

Napthenic acid, a principal component of Copper Naphthenate production, is a petrochemical byproduct, a byproduct of jet fuel production. Currently, the byproduct is concentrated by a processor and distilled by a third party and is purchased by Nisus. Most Carboxylic acids are 12-16 chain compounds and have an odor.  Our suppliers are having some success in further refining their product, which will allow us to reduce the odor. Basically, many of the compounds that volatilize are being removed.  The only products where there is an odor issue are is in the topical application products, which are frequently sold as a booster for treated product that are in service. 

Q7. Are there Naphthalene emissions from Copper Naphthenate products?

Napthalene is not a component of copper naphthenate, despite the similarity in their names. 

Q8. How long have borate products been marketed as insecticides?

Nisus was the first to market borates, beginning as a log home treatment, in the 1980's. 

Q9. Borates are generally expected to leach from wood upon exterior exposures. Nisus markets borate pre-treatment products designed to enhance primary treatments. Do subsequent treatments following the borate pre-treatment reduce borate leaching? Does Nisus market a `stand-alone' borate product that can be used in exterior applications?

When applied as a surface treatment, the Borate is allowed to soak in for a several days or sometimes longer. After it dries, then the product is pressure treated with Copper Naphthenate or creosote. The Borate makes the product a better treated product and the Copper Naphthenate or creosote locks the borate in place, so it won't leach out. Currently, this dual treatment is generally only used in railroad ties. 

III.  Preservative Treatment/Process

Q1. Are there new processes involving pre-, dual-, or post-application for Copper Naphthenate?  We noted things like a secondary emulsion treatment for CCA treated poles and KDAT for water borne treatments by some suppliers.  

See our answer above. Copper Naphthenate is an oil-based product and does not require further treatment to get the advantages of an oil-based surface, which is desirable in utility poles for climbing.  

Q2. Are there any anticipated changes in treatments, applications, treatment processes or any notable process changes that have occurred since 2007?

See our answer above regarding the changeover in the use of pentachlorophenol. Treatment controls that can be required for facilities using creosote and pentachlorophenol are not required for Copper Naphthenate treatment processes.  Controls include mechanical control of door openings and sprayer applications. 

IV.  Wood Products

Q1. Are there new (since 2007) wood products being pressure- or heat-treated with preservatives that we need to consider? 

Solid wood packing frequently now requires insecticide treatment or heat treatment.  But for heavy duty wood preservative products there are no new products on the market. 

V.  Green Certifiation

Q1. What green certifications do Nisus and Nisus customers participate in? 

For residential markets, we work with the Green Building Council and in the commercial market we work with LEED.  For organic requirements, we work with OMRI, the Organic Materials Review Institute.