Four approaches to reusing and recycling post-consumer paint include:

• paint exchanges;
• pains consolidation;
• paint blending; and
• paint reprocessing.

The four approaches vary considerably from each other. Paint exchanges represent reuse, while consolidation is more of a recycling activity. Blending and reprocessing are higher degrees of recycling, and each has its own associated problems and obstacles.

Paint exchanges are preferred by the paint and coatings industry because they are relatively free of restrictive barriers, such as developing adequate resale markets, liability concerns and regulatory barriers. Once paint is removed from its original container, then barriers to paint recycling must be given serious consideration by all involved in the local household hazardous waste program, including participating paint manufacturers.

Consolidation of latex paint may be a good method for recycling usable paint without too many barriers. However, this form of recycling may require extensive testing by the local government who is generally the customer for this type of paint to ensure that the paint is not contaminated with heavy metals, mercury, pesticides, bacteria or other materials, and that it meets the requirements of the Occupational Safety and Health Administration (OSHA). As the degree of recycling technology increases, so too do the potential barriers which may hinder paint recycling as a viable post-consumer paint management tool.

The easiest and least expensive method for reusing paint is paint exchanges. Paint exchanges have been coordinated in many communities across the United States, usually in conjunction with household hazardous waste collection events. While there is no standard determining factor, many communities consider leftover paint reusable if at least one-third of a gallon remains in the original container, the label is intact, and the paint has not been frozen or contaminated.

Paint exchanges may reduce the total volume of paint for disposal by 25 percent or more with increased community participation.

Paint left on exchange tables should first be inspected to make sure it is still usable. These usable paints may be donated to local community projects, theater groups, schools, churches and other groups or projects such as anti-graffiti campaigns. In addition, homeowners who want a little paint or a certain color of paint may pick up free paint at these exchanges, which are also referred to as "drop-and-swap" programs. It is advisable to label the paint for "exterior use only," since paint manufactured prior to 1991 may contain mercury. (The paint industry, working with the EPA, voluntarily ceased using mercury biocides in interior latex paints in 1990 and in exterior latex paints in 1991.)

Paint exchanges are most efficient when end-users can be identified before the paint is collected. In other words, paint is treated as a commodity and a "broker" finds a customer for the leftover paint. The paint is then transferred directly from the participant to the end-user. Through this system, the municipality decreases the need to manage leftover paint.

Paint consolidation generally produces a low-grade 100-percent recycled paint. This process is relatively inexpensive to implement and may effectively reduce the volume of latex paint for disposal by as much as 50 percent or more. Paint consolidation for reuse of solvent-based paint generally is not recommended; consolidation for eventual use in a fuel-blending program is more feasible. However, if the consolidated paint is destined for a paint manufacturer, expensive testing may be required to ensure that the paint is not contaminated and meets specific requirements, thus, reducing liability concerns for the manufacturer. Manufacturers will not generally accept any post-consumer paint for recycling which has not been extensively tested and screened for possible foreign materials, as well as for raw materials data.

During household hazardous waste collection events, good quality latex paint should be filtered, tested and consolidated into 55-gallon drums. Most programs separate the light and dark latex paints in different drums, producing a beige color and a brown or dark color. The paint should be tested for possible contamination before being repackaged into 5-gallon containers and either donated or sold at a nominal cost to local government contractors or community agencies. Some communities use this consolidated, recycled latex paint in anti-graffiti campaigns, which have been fairly successful. Generally, every drum or batch of the consolidated latex paint varies slightly, due to variations in paint quality and color. Solvent-based or alkyd paint consolidation f or reuse is not generally done at this time because of the complexity and incompatibility as well as other considerations of such paint formulations.

Paint blending involves participating paint manufacturers blending leftover paint with virgin materials to yield a new paint with a recycled content. Post-consumer paint is a minority constituent or filler in these batches, constituting about 10-20 percent of the finished product. Manufacturing wash water can also be blended into the paint product. In both of these situations, bacterial contamination of the latex paint is a major threat. This is one of the reasons why most paint manufacturers are very cautious about accepting any post-consumer paint without extensive testing. The resulting latex paint is generally intended for exterior use for anti-graffiti purposes. To NPCA's knowledge, a very few U.S. paint manufacturers regularly blend leftover post-consumer paint for sale, and they have specific contractual agreements with their state governments or municipalities.

Many paint manufacturers around the country recycle their own errant or odd batches of paint. However, all of this paint is pre-consumer and therefore, the manufacturer knows what is in it. The process is more complicated when dealing with post-consumer paint, and these complications may present several real barriers to paint recycling by this advanced method. The barriers to paint recycling are discussed in the following pages.

Blending post-consumer paint for use in an energy recovery system is widely used in the industry for solvent-based paints. Fuel blending is an ideal recycling activity to reuse unwanted or unused waste post-consumer solvent-based paints. Please note, however, that paint and related products may only be fuel blended if the BTU content is at least 5000 BTU. If the BTU content is less than 5000, it must be incinerated.

Latex paints generally are not blended for a fuel-to-energy program because they are low in energy value (BTU); however, small batches of latex may be blended with solvent-based paints for such a reuse program as long as the BTU value of the blend is relatively high (generally over 10,000 BTU/lb). Check with your local cement kiln operator or fuel-blender to see what is acceptable.

Paint reprocessing, or high-tech recycling, requires careful quality control during the sorting and reprocessing steps. Leftover paint should first be sorted to exclude paints that would compromise the quality of the finished product or that would render it hazardous. NPCA recommends that the paint be bulked into batches of 1,000 gallons or more. The characteristics of each batch should be tested using standard paint industry procedures. Paint color and characteristics should be adjusted with additives, until each batch meets a uniform internal standard. The 100-percent recycled paint would then be ready to be sold at retail.

In the United States, the limited high-tech paint recycling programs which exist only handle latex paint. Solvent-based paint recycling is not advised by the paint industry at this time because of the complexity of the paint materials and the high cost of handling and recycling solvent-based paints compared to other post-consumer paint management alternatives, such as waste-to-energy programs.

While the paint industry supports paint exchange programs, limited consolidation and fuel-blending programs, the industry has yet to reach a consensus on low-tech or high-tech paint recycling. Not only is it difficult to find a viable market for blended latex paint, but also, paint reprocessing presents many technical, regulatory, legal and marketing barriers for most paint manufacturers. Before manufacturers consider whether to actively participate in paint recycling programs, these obstacles must be addressed and overcome.

Recycling paint may sound like the perfect environmental solution to paint disposal but will it really solve the problem of leftover paint?

A typical paint manufacturer produces many, many different paints each formulated, tested and marketed to meet specific needs. One of the biggest misperceptions is that all latex paint is alike and all solvent-based paint is alike. In order to understand the wide diversity of paint product types, let's look at just architectural paints which include consumer paints. There are solvent- and water-based products; interior and exterior products; wall paint, trim paint, ceiling paint, floor and porch paint; stains and varnishes; concrete block and cement coatings; metal and corrosion resistant coatings; water-proofing elastomeric products; stain-blocking products; primers, sealers and surfacers; etc.

Unlike materials such as paper, cans or glass bottles, paint is not uniform in composition and is not intended to be thrown away. Paint is a very complex mixture which can easily be adulterated, by intention or by accident. Some people tend to use a half-empty paint can to dispose of other household wastes such as household cleaners, pesticides and motor oil. These contaminants are especially hard to detect in alkyd paints. This raises health and safety concerns. Since there is no way to know for sure what else is in paint cans when they come into a paint collection site, utmost care must be taken to ensure that the waste paint poses no health or safety threat to those individuals who must dispose of the waste paint.

The barriers to paint recycling discussed in this section address primarily low-tech and high-tech recycling as discussed in the previous section. Certainly, some of these barriers exist for consolidation/blending of paints, and these need to be considered by both the waste management officials and any paint manufacturer who wants to become involved in paint reuse and recycling programs.

While some of these barriers may be overcome through extensive discussions and contractual agreements between the local household hazardous waste program officials and a participating paint manufacturer, it must be clear that paint recycling is a voluntary activity at the local or regional level. Paint recycling should remain an activity discussed and agreed upon by a specific, participating paint manufacturer and local household hazardous waste/solid waste professionals.

Since there is no standard paint recycling protocol, different paint recycling programs have different methods of processing and testing post-consumer paint. Ideally, every container of paint collected should be thoroughly tested to ensure good quality, uncontaminated paint for recycling programs. Unfortunately, running a battery of tests on collected paint can be expensive, and most municipalities do not have adequate funds for such quality assurance testing that is necessitated by standards of both OSHA and the industry. This poses a major problem because household paint may not be adequately tested to satisfy the participating paint manufacturer, causing liability to increase. In addition, responsibility for bearing the testing and processing costs is a consideration. Neither paint manufacturers nor local waste management officials have extensive financial resources to fund large, complicated paint recycling programs. However, some paint recycling programs exist without exorbitant costs.

Even if funds are available, the average paint manufacturer would not accept residual paint as a raw material without extensive testing because of liability concerns. A typical full TCLP test in the Chicago area for a paint manufacturer can cost at a minimum $1,200; this would translate to approximately $6 to $7 per gallon of paint for testing. This cost may be reduced to a base of approximately $600-$800 by restricting the TCLP test to heavy metals content only.

In order for a participating paint manufacturer to accept post-consumer paint as a material for reuse in the manufacturing of paint, the post-consumer residual paint may need to be tested (and inspected) for the following (although tests may be done in aggregate to help reduce costs):

• Presence of any toxic, regulated materials, including mercury, lead, hexavalent chromium, cadmium, isocyanates, organic chlorides, etc.
• Presence of bacteria, fungus or enzymes.
• Non-volatile solids content.
• Pigment volume concentration.
• Titanium dioxide content.
• VOC content.
• Resin types and content.
• Presence of seeds, gels, dirt and/or grit.
• Color (L,a,b; or x,y,z format).

Most of this testing may be required by the participating paint manufacturer to ensure compliance with hazardous materials control legislation; some paint manufacturers may require less testing. The degree of testing should be discussed prior to any contractual agreement. An independent lab typically charges from $500 to $1,000 per sample for a full battery of tests for these requirements.

Contamination of paint with such components as pesticides, used oil or other foreign matter will have a major effect on a paint recycling program. Because a standard TCLP will not identify many hazardous constituents of old paint, it is difficult to determine what consumers may have mixed with the paint before bringing it to a paint collection program (see table below). Because contamination is of major concern to most paint manufacturers, extensive testing may be required before a typical paint manufacturer will even consider accepting post-consumer paint as a raw material for either low-tech or high-tech paint recycling. In addition, contamination again raises concerns about product and environmental liability and worker safety.

Latex paints pose a special problem since they may be contaminated by bacteria. With the voluntary withdrawal of mercurial biocide use in latex paints in 1990 in interior paints and in 1991 in exterior paints, concern with bacterial contamination has increased. In addition, there are chemicals that can kill the "good" bacteria, but once the product has been contaminated, enzymes produced by the bacteria are present and they create special problems that could make the mixture unstable and much more difficult to reuse in a recycling program that requires reprocessing of any kind.

One of the biggest obstacles to paint recycling is the imbalance in the basic economic equation of supply and demand. Currently, there is not a well-established niche market for recycled paint products. Many manufacturers participating in paint recycling programs are having difficulty finding markets for the paint. This causes the problem of a company having to stockpile large quantities of unmarketable, recycled paint. No one seems to want the product. Perhaps people perceive it to be inferior to new paints, or the lack of color choices is too limited (most recycled paint is available in either beige or a dirty brown color). Certainly, the quality of the recycled paint is generally inconsistent from batch to batch, and is poor compared to a virgin paint product. The shelf-life of recycled paint is relatively short in comparison to virgin paint. However, some programs have been successful because a well-defined market was identified prior to paint recycling, such as a local government purchasing agency. Canada's pilot paint recycling project, in which several manufacturers participated, is a prime example of too much recycled paint and not enough demand.

Some local governments have prepared bid specifications for recycled paint purchasing, but such accommodations do not overcome the major obstacles in paint recycling such as liability, cost, transportation and contamination as outlined below.

The cost of collecting, identifying, segregating, handling and testing paint with the idea of paint recycling may be expensive, and in the end, may produce only a small fraction of material suitable for consideration as a raw material to most paint manufacturers. Manufacturers also have to supply additional raw materials to add to the post-consumer paint in order to meet certain specifications (e.g., government procurement specifications) in addition to providing the packaging, labeling and labor to make the post-consumer paint usable, assuming that a market already exists.

Currently, recycled paints are being marketed at a cost of $2 to $7 per gallon, although, on average, recycling the paint can typically cost $7.20 per gallon. Since the current recycling programs generally consist of giving the paint away free, the manufacturers usually have to absorb the cost for recycling post-consumer paint, recouping little of the costs associated with processing. However, municipalities sometimes pay paint manufacturers $2 to $3 per gallon to take back the paint for reprocessing.

Currently, there are no federal regulations governing paint recycling or disposal. Household hazardous waste, including paint products, are exempted from stringent hazardous waste regulations under RCRA. However, while homeowners are not required to specifically treat their wastes before disposing of them in the garbage, those professionals who collect the household hazardous waste at a collection site are responsible for obtaining the proper operating permits. Some permanent facilities may be designated as TSD facilities, which require adherence to strict regulations. Generally, waste management contractors operate or dispose of household hazardous waste, and therefore, are permitted hazardous waste handlers. Paint manufacturers are not considered hazardous waste handlers, prompting many of those who may have considered participating in paint recycling programs to decline. In addition, paint manufacturers are not disposal facilities and cannot and will not accept hazardous waste which requires proper permits for handling under TSD regulations.

Participants in a paint recycling program may face liability concerns because of the number of chemical and biological contaminants post-consumer paint may contain, and because of the possible presence of discontinued or banned chemicals (e.g., mercury) in older post-consumer paints. There are many variables that make paint recycling unattractive to many paint manufacturers, and all of these issues should be considered and discussed openly.

Non-paint products by themselves generally present little health and safety concerns, if used in accordance with directions. Like paint, these formulated products are strictly regulated and labeled appropriately for consumer use. However, when these products find their way into paint, it is very difficult to determine if the contaminated paint is safe for recycling, and extensive testing of the paint may be needed in order to identify the possible contaminants. Without identification of contaminants, manufacturers cannot prepare labels that appropriately warn the manufacturer's employees about the product's hazards.

In addition, other liability factors should be considered, such as ensuring proper labeling and testing, as well as guarantees to home-owners and retailers. Little is known about the durability of the recycled paint, and even a little undetected contaminant may affect surfaces painted with the recycled paint.

Once collected, processed, and tested, post-consumer paint may be shipped to participating paint manufacturers for reprocessing under contractual agreement. Handling and packaging procedures for paints vary, depending on whether a product is classified as a hazardous material or not. (Note: a hazardous material is not necessarily a hazardous waste.) The Department of Transportation governs the shipping and carrying of hazardous materials. DOT's hazardous materials regulations are found in Title 49 of the Code of Federal Regulations.