Food Safety Tech (FST): What’s so important about IS0 17025 accreditation?
Shaw: The ISO 17025 standard is a gold standard for lab quality. The standard is system based, and not prescriptive, so there can be a lot of differences in how it’s implemented. ISO requires you to have a procedure to do something, it doesn’t tell you what that procedure is. For instance, the standard requires you to have a procedure for customer complaints, however the lab can either have a very basic system of recording and investigating these complaints, or it could process that complaint and get to the root cause, and correct the nonconformance, so that the problem wouldn’t be repeated. Similarly when it comes to personnel requirements, the standard can be interpreted as having competent people on staff, or having elaborate six-week long training programs and documenting this.
FST: How does laboratory design impact microbiology operations?
Shaw: Lab design is very important from both an operation and quality point of view. It’s important to keep in mind that you are dealing with potentially dangerous pathogens and contaminants, and after you have prepped and enriched the sample, and it’s positive for a pathogen, you have a huge number of microorganisms in that sample. You have to make sure that this is not moved back into the lab. Thus lab design has to ensure single directional flow of sample from one side of the lab to the other side, with both sample and personnel moving along the clean to dirty direction. Once samples come in, are prepped, enriched, incubated, and then tested, positive samples then are a threat to the lab, and the environment, in case there’s a spill or a bad technique in place.
From an efficiency point of view, LEAN is a big concept now. So lab design, if done well, can help realize efficiencies in consumables, personnel, minimizing foot traffic etc. If everything is set up correctly – in terms of reagents, equipment, testing kits etc – then you can reduce time and effort spent in gathering samples, and moving around the lab. At Eurofins, we take this very seriously. We have a team that’s dedicated to lab design process and engineering around our workflow, and believe investing resources in the necessary software system LIMS to drive up efficiencies.
FST: How should high risk samples be treated? Should customers notify the lab of hot samples?
Shaw: There are two schools of thought about this. The first one is we want to treat all samples the same, so that we don’t bias the technician. We barcode all samples in the same way, test them in the same way.
On the other hand, we don’t want to open the lab to unnecessary risk, and contaminate the lab. So we handle high-risk samples differently, by taking extra precautions. Sometimes, a customer can bring in a sample and say it has Salmonella, and needs to be tested. We will still run the sample through the same procedure, but will separate it from the other batches. We also have to take care to schedule testing of these positive samples carefully such as moving it towards the end of a shift or break.
FST: With changing rules for food safety testing, what’s changing with regards to documentation?
Shaw: It’s important, as always, to record anything that can affect the result of a test. Also clear time stamps must be documentation. When things happened, who did the preparation of the sample, who analyzed the sample? Consumption of media, test kits, chemicals and agents, or anything that was used in the analys, all must be clearly recorded. In some labs, all of the documentation is still in paper, and hence is a very manual process, while other labs are highly digitized and have the ability to track a lot of this information electronically.
FST: What are some practical challenges that food safety testing lab typically encounter?
Shaw: Labs typically face challenges with result validation, typos in documenting test results, and customer requests around retest situations. When it comes to reporting, it’s important to have a number of eyes looking at your data, to make sure that it makes complete sense. For instance, if you are testing a product for coliform bacteria, and specifically for E.coli, then the latter number cannot be higher than the total coliform number. If there is, it means there’s an issue with the analysis.
Typos with lab results, sample number etc. are other issues that every lab suffers on a day to day basis. Fundamentally, humans make errors, but as technology evolves, and systems learn to interface better with each other, such errors can be minimized.
Another challenge relates to situations when we have released the CoA and then the customer calls us to modify the lot numbers. This is a gray area, and potentially could become problematic. In such situations, when the customer requires something to changed, it’s prudent to have some kind of documentation about this, clearly specifying that it was a customer-initiated request. Of course, such situations also have an ethical component to it, so they need to be handled carefully.
Accommodating requests for retesting samples can also be a challenge. For instance, you test a sample on Day 1, and are also to test again on Day 3, you could get different results. Getting similar results with microorganisms, even when the samples are homogenized etc., is challenging and not realistic if you consider that the microorganism could increase or decrease in those few days.
Overall, Shaw encourages food companies to take a careful look at their food safety testing needs and the lab’s abilities. “Don’t just accept an ISO certificate. Ask to look at the labs, their processes etc. Good labs will encourage that, while the not so robust ones, may not accept that request, even though they have an ISO certificate, and that, in my mind, should raise a red flag,” explains Shaw.
I have a situation where a customer I process a product for, requests that only a single sample out of a production run of 40,000 is sent to a lab for APC,Coliform and other tests, and that the entire lot be disposed if that sample comes back above specs (20 for coliform). We are contending that we either have to have a larger sample for that run to provide a statistically valid sample size, or that we are allowed to send a 7 additional samples from the same time stamp for retest if the results come back positive. Who is right?