The cold chain is a chain of decisions.

A product passes through several organisations before it reaches the person who needs it. Each must control its part of the journey and make the next handoff work.

Who is responsible between two controlled environments?

A refrigerated shipment arrives on time. The transport record is available. The receiving cold room is operating correctly. But the product is still on the loading dock. Who is responsible for it now?

That interval concerns me. The vehicle and the receiving cold room can both operate correctly while responsibility for the product between them remains unclear.

Several organisations, one product

A pharmaceutical company operates within a much longer journey. Depending on the product, that journey may involve starting-material suppliers, manufacturing sites, storage providers, carriers, distributors, pharmacies and healthcare teams before the finished medicine reaches a patient.

Each participant operates a particular part of that journey. A manufacturer can oversee distribution without running every vehicle or storage facility. A carrier can document transport conditions while having limited information about what happened before collection or after delivery.

Claims of complete visibility need a precise scope. Which stages are covered? Who holds the records? Where does the picture stop?

Shared monitoring data can improve that picture. The ability to act still depends on the people and organisations responsible for each operation.

The handoff needs an owner

When responsibility passes between organisations, the arrangements need to be understood by both sides. The required storage conditions, the monitoring evidence, the acceptance process and the handling of exceptions all need to travel with the product.

At the receiving dock, who checks the temperature record? Who can place the shipment on hold? Who assesses an excursion? Where is the product kept while that decision is pending? Who is contacted if the record is missing?

The answers need to be agreed before the vehicle arrives. A signature on a delivery document may say very little about who assessed the temperature history.

The European Commission’s GDP guidelines for human medicines address written agreements for outsourced activities and responsibilities during transport. They also make oversight of outsourced activities part of the quality system. Delegating an operation requires a clear allocation of duties and appropriate supervision.

A study that stayed with me

This question of where control ends takes me back to the early years of OCEASOFT. We participated in work on the food cold chain, and I remember the attention it brought to what happened after the consumer left the shop.

Cemagref researchers Évelyne Derens, B. Palagos and J. Guilpart published The cold chain of chilled products under supervision in France in 2006. Their method followed refrigerated foods from the end of production through to the consumer, using small temperature recorders concealed inside the products.

The paper reports 314 usable product histories, representing more than 3,800 days of recording. It found that around three quarters of the products had been kept in good or very good temperature conditions, while the most serious departures from recommendations occurred particularly towards the end of the chain.

What stayed with me was the importance of the domestic refrigerator. The effort invested in professional storage and transport could be followed by conditions that those professionals neither operated nor continuously observed.

The product continues its journey after it leaves the part we can see. That observation has stayed with me.

The person at the end of the chain

Food and medicines both end up in the human body. That is what gives these storage and transport decisions their significance. Someone will eat the food or receive the medicine, relying on the product to remain safe and suitable for its intended use.

A temperature excursion raises a product-specific question. Its consequences depend on the exposure and the evidence available for that product. In food, inadequate temperature control can allow microbial hazards to develop. For medicines, an excursion can affect stability, quality or potency. The assessment needs to establish whether the product can still be used safely and as intended.

That is why I want a clear process for recognising an excursion, preserving its record and getting it assessed by the appropriate people. A later return to the required temperature does not, by itself, demonstrate that the product remains suitable for use.

After dispensing, the storage requirement continues

The food study tells us nothing about the stability of a particular medicine. It does make me ask what happens after dispensing: how does the patient maintain the conditions that product requires?

For a medicine that needs refrigerated storage, the patient or carer needs clear instructions for the journey home and subsequent storage, together with a contact if something goes wrong. Those arrangements should reflect the product’s approved requirements and the relevant healthcare guidance.

The final handoff deserves the same attention as the earlier ones. It may involve someone with far less equipment, information or training than the professional teams upstream.

What I expect from each participant

I want each organisation to be able to explain how it controls its own activities, what evidence supports that control and how it prepares the next participant to take over.

Good performance within individual segments needs to be joined by clear responsibilities at their boundaries. Otherwise, a gap can remain between two operations that each appear satisfactory on their own.

Follow the product across a handoff. At that moment, who is looking after it, what do they know, and what can they do if the conditions are wrong?