Just about anything that is shipped in bulk today is shipped on wood or plastic pallets. Most industries, including automotive, chemical, food, paper, retail, etc., use pallets to transport their products from manufacturer to store. It is estimated that just in the United States, nearly two billion pallets are used every year to ship products. The vast majority of these pallets are made of wood. Only 2% are made of plastic, 1% are made of a wood composite, and less than 1% are made from metal.
Why are wood pallets so popular? Largely because they are cheap, durable, and easy to repair. The wood from a broken pallet can easily be recycled into a new pallet, and the construction of the pallets makes them unlikely to break and easy to repair when they do. They can often make several trips from plant to warehouse to distribution center to retail store and back without needing any maintenance. They are so inexpensive that many companies will simply give their old pallets away for firewood or to be grinded up into wood chips when they are no longer functional.
While pallets are used in all industries careful consideration should be made before using wood pallets in the supply chain for food and pharmaceuticals production plants. Market forces have pushed pallet manufacturers to build cheaper pallets with lower standards, capacities and deck coverage. In order to lower the price inexpensive soft woods are often used with fewer fasteners and nails making them susceptible to breakage and splintering. The soft wood itself is fibrous and porous because it is not sealed, allowing the absorption of moisture, liquids, and chemicals; because of this multiuse wood pallets are rarely washed or treated in between use.
This also means that wood pallets collect bacteria, dirt, debris, chemicals, particles of food or pharmaceutical ingredients and carry those particulates into the plant and production areas. The FDA conducted a study of wood pallets and found that about 10% played host to E. Coli, Salmonella, and other harmful, disease-causing bacteria. While 10% may not sound like a large fraction of all wood pallets used in the US, this still equates to hundreds of thousands of pallets which makes a consumer extremely likely to come into contact with food or drug products that have been shipped on a contaminated pallet.
Just in the last year alone, there have been recalls of peanut butter, frozen chicken, pet food, bacon, ice cream, hamburger, and beef. While none of the contamination events that triggered these recalls have fingered pallets as the contaminating substance, food manufacturers are starting to become more and more aware of how bacteria is finding its way into their manufacturing plants.
Though none of the recalls this year were blamed on contaminated shipping pallets, the recall of thousands of bottles of Tylenol Arthritis Pain Caplets at the end of 2010 was attributed to wood pallets. The customers who reported the contamination said that the drugs had a musty scent and that after taking them, they experienced stomach pains, vomiting, and diarrhea. After an investigation into what could have contaminated the pills, Tylenol eventually determined that it was a fungicide used on the lumber that their shipping pallets were constructed from. When the fungicide encountered moisture, it broke down and released a chemical that found its way into the drugs.
Both the raw materials used to make products in the food and drug industries and those finished products are shipped on inexpensive wood pallets, leading many to be concerned about whether or not those products are actually safe for consumption. With wood pallets being so ubiquitous and a necessary part of so many industries, is there a way to prevent this type of contamination?
Plastic pallets have many of the same benefits of wood pallets. They are inexpensive, can be reused and reused, and can be recycled. They have the additional benefits of being completely non-porous and they have the ability to be sanitized before each use. They are more expensive than wood pallets, but because they last longer than their wooden counterparts, they are ultimately a better investment, especially because they are unlikely to harbor the dangerous bacteria or substances that wood can. Plastic pallets can act as an intermediary for products shipped on wooden pallets. If loads are transferred to plastic pallets before entering a production area, there is a far lower risk of contamination than with wood pallets, and they can then be cleaned by workers or with a pallet washing system made specifically for this purpose.