Toxic Tails: A Race Against Time to Determine Dioxins

The sound of a scream in the early hours of a misty morning awoke the tranquil village of Foghaven. Through the thick fog that blanketed the streets, a ghastly figure emerged, its silhouette barely distinguishable yet unmistakably ominous. Residents peered from behind curtains, their hearts pounding with fear. The figure’s approach was slow, and as it came into view, the villagers could see that the skin seemed ravaged by an unknown affliction, resembling a creature risen from the grave. News spread quickly about the zombie of Foghaven, but this was no zombie, but something even more disturbing: a stark reminder of the darkness that can lurk beneath the surface of everyday life—the misty morning had revealed a nightmare, not cloaked in fantasy but in the chilling cloak of reality.

📂 Case overview: A client is under pressure as the government needs comprehensive data about dioxin levels in their produce. The deadline is looming, and failure to provide the necessary information could mean severe repercussions for the client. Can the detectives find a way to drastically speed up their process?

Shallot Holmes was planning to treat the detectives to a well-deserved day out as they had successfully helped a sugarcane mill increase its efficiency and profitability. However, when he arrived at the office, the detectives were glued to their mobile phones, transfixed by the mystery of the zombie of Foghaven that had spread nationwide through social media. Holmes had been blissfully unaware of the horror unfolding in Foghaven, but as soon as he was shown pictures of the apparent ‘zombie’, he had an idea as to what the problem might be. “Chloracne,” said Homes to the bemusement of the detectives. Seeing that the detectives didn’t know what he was talking about, he explained his theory.

“Chloracne is a skin condition often associated with exposure to certain toxic chemicals, particularly dioxins, and has been a concern for environmental and medical research. Do you remember the conference we attended about dioxins?” asks Holmes. “Oh yes, I remember, and I also worked on a case about the presence of dioxins in food,” says Cornlumbo just before the phone rings. Holmes answers the call and receives the details of their next case. “Well, detectives, my suspicions were correct; it was chloracne, and I have just heard from a fish supplier that they fear that the dioxins were from their fish. Due to the attention this case has received, the government is desperate to ensure no more outbreaks of chloracne. The client has been given the task of testing huge amounts of fish in a short period of time to meet the government's strict deadline. They began testing but quickly realized that using their current methods, they would never complete the task in time. We need to formulate a plan to speed up their process and pinpoint the source of the contaminated fish,” says Holmes.

The client has been given the task of testing huge amounts of fish in a short period of time. We need to formulate a plan to speed up their process and pinpoint the source of the contaminated fish.

How can you speed up the process of dioxin analysis?

Holmes breaks down the process of analyzing dioxins in fish and explains to the detectives the importance of toxic equivalency factors (TEFs) and the TEF values for individual congeners and their concentration, which is used to calculate Toxic Equivalents (TEQs) for toxicologists. Dioxin content is expressed in relation to fat content. Therefore, fat extraction of the sample is necessary. The client has been performing this step using the Soxhlet extraction method, which takes several hours. Once completed, they must also perform gravimetric fat determination, whereby they redissolve the extract and perform a lengthy clean-up procedure to purify the extract for GC-MS quantification. Cornlumbo suggests using Pressurized Solvent Extraction (PSE), which uses elevated temperature and pressure to reduce the extraction time from hours to minutes. This is because of improved mass transfer due to higher analyte solubility. More of the analyte can dissolve in the solvent, making the extraction process more effective. There is also enhanced penetration as the high pressure helps the solvent penetrate the sample. An increase of normal pressure (pn) to increased pressure (p2) maintains the sample in the liquid state at higher temperatures. If pressure is not increased, the solvent might turn into a gas and be less effective for extraction. “Exactly, this will definitely be key to helping the client speed up their process, but will it be enough?” says Holmes.

Pressurized Solvent Extraction (PSE) uses elevated temperature and pressure to reduce the extraction time from hours to minutes.

How can parallel extraction increase efficiency?

Miss Mapple highlights that some PSE systems can handle multiple samples simultaneously and that Parallel Extraction will not only speed up the process but also save space, use less energy, and reduce solvent consumption when compared to classical extraction and other techniques. “That’s right, and some modern equipment can also be integrated with other instruments that also process samples simultaneously , such as parallel evaporation systems. This can save huge amounts of time, increase safety, ensure reproducibility, and reduce the chances of cross-contamination as the different instruments use the same racks – thus avoiding transfer steps. Some parallel extraction instruments can handle up to six samples at once and have individual inlet valves for each position, as well as individual pressure sensors. If a blockage occurs in one position, a troubleshooting wizard automatically deactivates this position, and the extraction process for all other positions continues,” says Holmes. “Also, the clean-up processes the client performs can also be automated by modern instruments, further reducing processing time and the amount of solvent required for the procedure,” says Nancy Beef.

Parallel Extraction will speed up the process, save space, use less energy, and reduce solvent consumption compared to classical extraction and other techniques.

Can parallel extraction also speed up environmental analysis?

Holmes gathers all the data provided by the detectives and passes it on to the client, who immediately implements their strategies to speed up their process. A few days pass, and Holmes gets another call from the client. Not only did the use of parallel extraction and evaporation lead to an increase in the speed of their analysis, but the client also shared the information with other government departments struggling to meet the strict deadlines imposed. The government had also demanded an analysis of waterways, soil, and air for Persistent Organic Pollutants (POPs).

Thanks to the help of the detectives, all the departments got their analysis done in time, and the case was solved. It was discovered that the fish from a particular waterway had toxic levels of dioxins encased in their fatty tissues. The waterway and surrounding soil were also analyzed, and it was discovered that industrial waste had been dumped in the area. The offending company was heavily fined and ordered to rectify the problem. The detectives were ecstatic; not only had they solved the mystery of the Foghaven zombie, but they also raised awareness of a serious environmental issue and helped improve the ecological health of the area.