In no other industry is the demand for sanitation higher than it is in pharmaceuticals. Companies making everything from over-the-counter pain remedies to life-saving cancer drugs are expected by the public to manufacture products with 100% quality. As a result, we see manufacturing built around robust processes, which lend themselves to frequent, thorough cleaning and disinfection.
Inventory controls have become more sophisticated, diminishing the risk of using wrong or out-of-date raw materials.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.