Getting Value from Your Environmental Monitoring Data

Once an investigation has been triggered, a multidisciplinary team (probably the same team that devised the routine monitoring program) should meet and discuss what is known and what is unknown about the issue. This team should include members who can inject critical viewpoints in the investigation, often experts from production, sanitation, quality assurance, maintenance, engineering, or any other areas that might contribute to the investigation. This team should interview other employees and check records to determine if any unusual events happened before or during the contamination event. For example, were there any unusual moisture events, such as a roof leak, power failure, construction, formulation or process change, etc.? Answering these types of questions often leads to multiple theories that need to be followed up with additional testing and fact finding.

As EMPs began to mature, many groups found that mapping is a critical part of data management. Being able to visualize which sites have been sampled and which have tested positive or negative is extremely valuable in helping to solve contamination issues and continuously improve the EMP. Mapping can range from a simple drawing pinned on the wall with multiple Magic Markers to indicate positive and negative findings, to sophisticated computer programs (see Figure 3). A map will typically show two dimensions, but it is also important to somehow capture the dimension of time. Being able to look back over a year’s worth of data to see if certain areas or related practices are linked to a higher occurrence of positives can help pinpoint problems. It is also important to have historical references. Many facilities unfortunately have high turnover of personnel. Having maps and other documentation to help illuminate past issues, investigations, and corrective actions can be important to prevent history from repeating itself.

Every environmental positive is not created equal. The reaction to a positive in a Zone 3 drain, far away from exposed RTE product will be much different from the reaction to a Zone 1 product contact positive. The EMP team needs to have a system that knows when to initiate and escalate the investigation and corrective action activities commensurate with the risk implied by the positive sample finding(s). Being able to visualize a series of positives in relation to the physical layout of the facility, process flow, and employee activities can greatly aid in informing the direction of the investigation and corrective actions and help keep the pathogen out of the finished product. The concept of “seek and destroy” means that the EMP teams seek out the target in the most likely places, sampling areas that are difficult to clean and sanitize (and therefore also difficult to reach for sampling). This often involves very complete and careful disassembly of complex equipment while sampling each part. Then the team destroys the target organism or growth niche by seeking the root cause, implementing a permanent fix, and then verifying that the issue truly has been permanently eradicated.

Sharing EMP data between similar facilities has played an important role in helping facilities improve their EMPs. Some of the earliest data sharing efforts were between facilities owned by the same company. It then expanded to supplier groups, meeting at a common customer, and then various trade associations. Understanding where similar facilities have found environmental pathogen problem areas have allowed EMPs to greatly accelerate their effectiveness.

Another important tool in environmental pathogen investigations is the use of strain tracking. One of the earliest examples of strain tracking was the use of serogroup or serotype data to track individual strains of Salmonella. Today we can differentiate to an even higher degree using methods such as ribotyping or whole genome sequencing to differentiate between closely related targets. The ability to determine whether a facility has a house pet (an environmental pathogen that is well-adapted to the facility conditions and is isolated routinely and over long periods of time) or house pests (transient strains that are introduced from outside the facility and are then eliminated) can be key. Regulators that find repeat occurrences of a house pet may determine that the facility is operating under insanitary conditions, with very serious consequences to continuing operation of that facility. Many companies are incorporating strain tracking into their EMPs to understand persistence and better protect public health.

Improving Protocols

During investigations and corrective actions, it has often been found that the process flow has contributed to a contamination issue. For example, mapping may indicate that a higher level of Salmonella positives has been found on the floor in the hallway leading to a trash compactor. After further investigation, it is found that there is moisture from rain events that is entering the trash compactor, causing growth of Salmonella. Steps in improving this situation include, better staging of garbage, having special footwear dedicated to the area, and applying a dry floor sanitizer powder. A more permanent fix can then be worked on, going to the root cause, and fixing the problem with the ingress of moisture into the area.