Inventory controls have become more sophisticated, diminishing the risk of using wrong or out-of-date raw materials. Equipment cleaning and disinfection is minimizing cross contamination between batches.
In every continuous improvement process, you eliminate the largest obstacles to quality first and work your way down the list. Often nearing the bottom of this list are pallets. Pallets are one of the most universal components of our distribution network and, as such, they became almost invisible. That is, until the culprit of some costly product recalls turned out to be the facility’s material handling equipment and pallets. Before such product integrity problems were traced back to these workhorses, manufacturers didn’t give pallets much thought beyond making sure they had the right size and strength.
PALLET BASICS FOR PHARMA FACILITIES
The purpose of a pallet is to enable the rapid, inexpensive movement of goods by making them easily accessible to mechanical handling, i.e., forklifts and pallet jacks. The three primary materials used to make pallets are wood, plastic and metal. Each material comes with its own set of benefits and challenges, making certain pallet types more suitable than others for drug manufacturing environments. Pharmaceutical manufacturers must understand how these different pallet materials can impact their facility and the quality of their final product.
When comparing pallet materials, wood pallets pose the most challenges to sanitation. The first and most obvious challenge is that of housekeeping. It is not uncommon for wood pallets to be damaged by handling equipment. Wood particles and nails can be broken loose, causing unsightly litter on the floor. These loose fragments pose significant contamination risks in pharmaceutical manufacturing facilities, especially if the pallets are being used with any lifting and dumping equipment that would place them above processing machinery.
In addition, exposed nails are a physical risk to employees as a source of cuts or punctures. The flooring in pharmaceutical facilities can also be damaged by the nails and jagged edges characteristic of wood pallets.
However, as has been shown by huge product recalls, it is the absorptive nature of wood that presents the greatest risk to product integrity. Water absorbed into a wooden pallet can become a breeding ground for bacteria and microorganisms.
A 2010 report from ABC News citing a study of wooden pallets in the food industry found that a significant portion of the pallets were contaminated with E.coli, salmonella or listeria. Moisture in the wood allowed for the growth of these pathogens. To combat the issue, wood pallet manufacturers have used the absorptive nature of wood to their advantage by applying pesticides and fungicides to prevent the pallets from becoming breeding grounds for contaminants. However, multiple incidents from 2009 to 2011 have shown how the treatment of wood pallets can backfire into tremendously costly product recalls.
Wood Pallets at the Root of Drug Recalls
Following consumer reports of pills having an unusual mildew-like odor that was associated with nausea, stomach pain, vomiting and diarrhea, FDA investigations determined that 2,4,6-tribromophenol (TBP), a fungicide/flame retardant chemical, was the primary cause of product recalls for three different pharmaceutical manufacturers. The initial cases took place from 2009 to 2011 with Johnson and Johnson, Depomed and Pfizer — each having consumer complaints and subsequent recalls that were traced back to wooden pallets treated with TBP.
Analysis revealed that the pallet moisture content exceeded the 13 percent limit, which allowed for fungal growth. The reaction of the fungi with the TBP resulted in the production of 2,4,6-Tribromoanisole (TBA), a highly volatile chemical that gives off a moldy, foul odor and is associated with nausea, vomiting and diarrhea. Including additional cases in 2011, it is likely that the industry cost of pallet contamination exceeded $1 billion, not to mention the loss of reputation. These incidents led to the following statement from the FDA:
“FDA recommends that manufacturers and distributors take precautions to prevent the use of wood products treated with or exposed to a halogenated phenolic preservative [such as TBP] anywhere in the supply chain. This includes all facilities that manufacture, hold or distribute drug products, components or packaging materials. We recommend that manufacturers not store drug products, components or packaging materials near wood or wood-derived storage materials unless there is assurance that the wood material has not been treated with a halogenated phenolic preservative.”
Plastic provides a stark contrast to wood from a sanitation perspective. Polyethylene is the primary material used to manufacture plastic pallets. Since this material is inert, very little sticks to it. Plastic pallets can be readily washed and disinfected, making them ideal for the support of a clean, contaminant-free manufacturing environment.
The inherent resilience of plastic pallets makes them ideal for multiple-use applications where they provide both sanitary conditions and long-term cost savings. The relative softness of the plastic means that damage to floors and equipment is virtually eliminated. And typically, plastic pallets are the lightest option with the lowest probability of causing employee injuries.
Safety Measures for Using Plastic Pallets
The downside of this material is the reduced friction it provides between the pallet and the product it is carrying. Care needs to be exercised by forklift operators to avoid sharp turns that can destabilize the load and cause spills. Some plastic pallet manufacturers have addressed this issue through the application of traction media on the pallet deck, or by molding ribs on the face of their pallet to physically locate and secure the load.
Additional safety consideration should be given to plastics in the event of fire. Although it takes higher temperatures to ignite plastic over wood, the resultant fire burns hotter. Some plastic manufacturers have integrated flame-retardant additives to their products, but these additives have led to contamination problems similar to those caused by the pesticide and fungicide chemical treatments used on wood pallets. Depending on a facility’s insurance requirements, changing out fire sprinkler heads to allow higher water flow may be an acceptable safety measure for pharmaceutical plants using plastic pallets.
Pallets constructed from metals such as aluminum and stainless steel offer sanitary advantages like those provided by plastic pallets. In fact, since pharma manufacturers have cleaning protocols for metals based on their machinery cleaning processes, the sanitization of metal pallets falls within well-known procedures.
Although metal pallets do not share the characteristic of softness with their plastic counterparts, metal’s strength makes it unlikely that aluminum or steel fragments will result from normal material handling operations.
Two primary downsides of metal pallets are typically weight and hardness. Metal pallets can be damaging to the pristine, expensive flooring found in most pharmaceutical facilities. Scratched floor surfaces can be a constant source of maintenance costs and can increase sanitation needs.
EVALUATING PALLET COSTS
Wood represents the lowest up-front cost for the mass handling of goods, with more than 95 percent of pallets in use worldwide being constructed of wood. Plastic and metal represent a significant jump in initial price, but usually end up saving manufacturers money in the long run because of the longevity these materials provide. Durable plastic and metal pallets typically outlast wood by a factor of 10-15 times.
From a pharmaceutical perspective, the true cost of pallets must take into account a material’s potential for contamination issues and resultant product recalls. To date, drug recalls due to contamination originating from pallets have only been traced back to wood. The loss of both revenue and reputation associated with such recalls creates a choice between plastic pallets and metal pallets for many pharmaceutical facility operators.
Several pharma manufacturers receive raw materials on wood pallets and immediately transfer the loads over to plastic pallets, which are sanitized before bringing goods into the manufacturing facility. On the other end of the production process, once their pharmaceuticals have been securely packaged, these manufacturers bring finished goods out of their plant on plastic pallets and then transfer the products to wood pallets for final shipment to the customer. This allows the manufacturer to have maximum control over the sanitation of their processing environment while receiving long-term value from their plastic pallets.
Choosing the right pallet type for your pharmaceutical facility requires more than an evaluation of black-and-white figures. It requires an understanding of the role material-handling equipment plays in your sanitation efforts throughout the production process. The increased risk of contamination that comes with lower upfront costs is something all plant operators should evaluate before introducing wood pallets to their facility. The reduced surface friction of plastic pallets and the maintenance needs often associated with metal pallets are concerns that should factor into an operator’s decision as well. Ultimately, the safety and well-being of your end-users should be your guide in choosing the right pallet type for your pharmaceutical facility.
ABOUT THE AUTHOR:
Peter Connors is the founder of Remcon Plastics, Inc., a plastics manufacturer specializing in material handling solutions for the food processing and pharmaceutical industries. Remcon’s bins, totes, pallets, and wide selection of material handling containers are rotationally molded to provide maximum durability and long-term value.