TNO has developed a method for rapidly detecting exposure to benzene. This is a nice example of personalized sensing, a type of sensor system that is used to better manage environmental impacts on people. What sets this method apart from the rest is its user friendliness, its ability to deliver on-site read outs, and the fact that the results are available within just a few hours.
Prolonged exposure to some of the substances in natural gas and oil can be harmful to health. Accordingly, the producers of oil products take all possible measures to protect their employees. Biomonitoring (the measurement of levels of harmful substances in workers’ urine) shows when, and to what extent, people are being exposed to risks. Benzene is one such harmful substance. Low levels in the body are legally permitted.
Waiting for the results
The method that is currently used to test for the presence of benzene in workers is rather cumbersome. From the moment that samples are taken, it can sometimes take up to several weeks before the results are known. This is because the urine samples are tested in specialized laboratories. In addition, samples from oil platforms or other remote areas, for example, are often transported on regular helicopter flights, which may not be scheduled every day.
A new test method
Shell looked for a faster and more practical approach. Jan Urbanus, the Manager of Exposure and Health Analytical Sciences at Shell Health explains that "First and foremost, we want to be able to intervene immediately, if necessary. For instance, faster access to test results enables us to modify working procedures the very next day, if necessary. In addition, we see it as our duty to contribute to general knowledge about exposure to chemicals in the workplace. We want to greatly expand the scope and frequency of these measurements, and not only in situations where increased risk may be involved." Shell Health found TNO to be a very effective partner. Jan points out that TNO’s staff includes analysts with the requisite knowledge of occupational hygiene. "Equally important, however, is their ability to commercialize applications. Market research and feasibility studies are part and parcel of the range of services they offer. TNO is also able to identify the right partners and get them involved."
On-site field test
The new test method involves fewer steps and has a lower detection limit than its predecessor. Anjoeka Pronk, senior Occupational and Environmental Health Scientist at TNO, explains that "We have reduced the complex analytical method to a few simple steps, with a throughput time of just a few hours. We have also boosted the method’s sensitivity, enabling us to measure values below the current occupational exposure limit. Next, we scrutinized the entire process, from the point at which the urine sample was taken through to the test itself. This involved questions such as which laboratory instruments are required, and which ones can be used for this particular application? For example, how do you take urine samples in the field? How do you heat them to 37°C, the temperature at which the test has to be carried out? Ultimately, occupational hygienists or nurses should be able to perform these procedures on-site, without any problems, thus eliminating the need for a specialized lab."
“We want to greatly expand the scope and frequency of these measurements, and not only in situations where increased risk may be involved”
Read out on site
The first phase of the project has now been completed. The modified analytical method has been validated in the laboratory. However, complex read-out devices are still needed to detect the breakdown product of benzene. Thus, the next step focuses on the development of a compact and user-friendly version of these read-out devices that can be used to read out the results of this analytical method on site. Anjoeka adds that "We want to develop this device in cooperation with a company that manufactures equipment for measuring pollutants. The ultimate aim is for this test method to be made commercially available to the oil and gas industry in particular, and to industry in general."
Anjoeka adds that similar methods can be used to detect exposure to various other harmful substances. "We are already exploring the option of developing a similar analytical method for PAHs (Polycyclic aromatic hydrocarbons, which are harmful substances generated when organic matter burns at high temperatures, ed.). Our goals include developing a device that can provide read outs for a range of different substances that can be harmful in certain quantities."
Measurement is the key
The new method of testing is more than just a convenient, well-thought-out ‘on the fly’ solution for quickly detecting if exposures exceed the exposure limits. It opens the door to more wide ranging measurements. The greater the range of assessed situations, the more effective our ability to determine when and where risks can occur. It offers the option of implementing safety measures in advance. That input can help the petrochemical industry to manage risk even more effectively than it does at the moment. The ultimate aim is to restrict people’s exposure to harmful substances to an absolute minimum. For every single worker, in workplaces everywhere.
What is benzene?
Benzene is a volatile substance that is released in the production or use of oil products such as diesel and gasoline. Should this be a cause for concern? Generally speaking, no. This is because benzene is only harmful to health when large quantities and prolonged exposure are involved.