Climate change threat to air cargo pharma shipments
03 / 03 / 2015
EXPOSURE to extreme temperatures ruined more air cargo pharma shipments than ever before last year, and is driving this traffic to ocean carriers, say experts.
Their research shows that the past 12 months witnessed a series of unprecedented global temperature extremes and, as a result, some pharma air cargo distributors experienced large losses.
They were unprepared for the sudden temperature events such as the recent record-breaking heatwave in parts of South America and other unexpected temperature highs and lows experienced around the world.
"As the frequency and intensity of extreme weather events accelerates so does the need for improved temperature control of pharmaceutical products during their transportation to market," advises cool-chain expert Tony Wright of Excelsius, a respected cool-chain consultancy.
In recent months the world has witnessed a succession of temperature extremes generally attributed to global warming and believed to be part of a long-term pattern of greater weather severity and uncertainty, he notes.
It is a trend that has not gone unnoticed by an industry that relies on being able to keep goods in transit under strictly-controlled temperature conditions.
“Solar radiation spikes during air handling operations have become one of the weakest links in the pharmaceutical cool-chain, a problem that is causing some manufacturers to switch from fast and efficient air carriage to the considerably slower sea freight.
"Solar radiation is a prime cause of airfreight temperature excursions," continues Wright. Even brief exposure can be fatal for some shipments.
"This is a huge issue for major pharma companies which at any given point in time will have millions of dollars worth of merchandise in transit across the globe.
“A single temperature excursion can wipe out the entire value of a shipment, causing enormous commercial, logistical and reputational loss," he warns.
One solution lies in adequate physical defences against sudden exposure to the weather.
New triple-action Tyvek® air cargo covers from DuPont claim to be “a reliable and affordable means” of protecting pharmaceutical products that must be kept within the ‘controlled room temperature’ (CRT) temperature band of +15°C to +25°C – in accordance with the latest EU legislation.
During validation tests on the effects of solar radiation on palletised pharma products, Dupont found that temperature spikes of up to 15°C above ambient are regularly measured under normal outdoor air cargo conditions.
Other similar direct sunlight tests found surface temperatures as high as 70°C or more and these are temperatures that can be further magnified by local conditions such as the ‘mirror’ effect of nearby glass or metal clad buildings.
“The problem doesn’t stop there,” says a statement. “The use of clear or black cargo coverings creates a very powerful ‘greenhouse’ effect as the sun’s rays are absorbed and trapped.”
This is another phenomenon observed in the validation tests. Temperature differences of as much as 43°C have been discovered between clear shrinkwrap and Tyvek when exposed to solar radiation during recent tests in Florida.
“This is because common packaging materials such as stretchwrap and bubblewrap can provide a ‘greenhouse effect’, by trapping heat and increasing the surface temperature of the pharma merchandise way beyond the surrounding air temperature,” says Dupont.
The triple-action Tyvek air cargo covers restrict this solar heat gain because of the fabric’s exceptional reflective properties in both the visible and infrared radiation wavelengths.
Aynur Rasulova-Rzepa, a special products consultant and manager at Dubai cargo agency International Transport Services, notes that summer temperatures in the shade in the Gulf city are routinely in the mid-40s but can easily be several degrees higher than that during particularly hot spells.
These, however, are the temperatures in the shade. Where pharmaceutical shipments are exposed to direct sunshine the surface temperature and the product packaging can easily combine to reach dangerous levels.
"Many route qualification programmes rely on data derived from average ambient temperature conditions and fail to take into account the huge solar exposure effects that can be encountered during loading and off-loading operations, often the result of unplanned delays or disruptions," says Aynur.
"Even brief exposures and occasional sunny intervals can cause huge and surprisingly fast temperature spikes."