Chlorinated paraffins in hinges of kitchen appliances

Abstract

Chlorinated paraffins (CPs) are anthropogenic pollutants of growing environmental concern. These highly complex mixtures of thousands of homologs and congeners are usually applied as additives in lubricants or as flame retardants and plasticizers in polymers and paints. Recent studies indicated the presence of high amounts of CPs in the kitchen environment whose sources could not be unequivocally identified. One option was the use of CPs as or in lubricants of hinges. To test this hypothesis, we performed wipe tests on lubricants on 29 hinges of different types of kitchen appliances (refrigerators, baking ovens, dishwashers, freezers, microwave oven, pasta machine, food processor, steam cooker) and analyzed them for short-chain CPs (SCCPs) and medium-chain CPs (MCCPs). CPs were detected in 21 samples (72%). Per wipe, SCCP concentrations ranged between 0.02 and 10 µg (median 0.23 µg), while MCCPs ranged from 0.09 to 750 µg (median 1.0 µg). Highest MCCP amounts (380 and 750 µg per wipe, respectively) were determined in new and unused appliances. A medium correlation between SCCP content and appliance age was observed, but no additional statistic correlation between SCCP/MCCP amount and appliance type or manufacturer could be observed. CPs released from hinges by volatilization, abrasion, and cleaning processes could enter the environment and come in contact with persons living in the corresponding households.

A fast gas chromatography coupled with electron capture negative ion mass spectrometry in selected ion monitoring mode screening method for short‐chain and medium‐chain chlorinated paraffins

“…Scan time per ion was 62 ms for the developed GC/ECNI-MS-SIM screening method, whereas it was 28 ms for the comprehensive GC/ECNI-MS-SIM method. CP quantification was carried out analogously to the procedure of Sprengel and Vetter, 15 which was modified from Reth et al 25 isotope ratios as described previously by Sprengel and Vetter. 6 CP concentrations that gave a signal of the most abundant formed ion with a signal-to-noise ratio of 10 and 3, respectively, were considered as limits of quantification (LOQ) and limits of detection (LOD) of the single chain CP standards measured with the screening method.…”

“…Industrially produced since the 1930s, and used in different bulk applications (e.g., as lubricants, cutting fluids, plasticizers, and flame retardants 3,6–11 ), CPs are one of the industrial chemicals with the highest production volumes of currently more than 1 million tons per year 8,12–14 . Despite this versatility, SCCPs and MCCPs were shown to have detrimental environmental properties such as persistence, lipophilia, and—at least partly—(eco)toxicity 5,7,15 . Gradually, this group of anthropogenic pollutants has been detected worldwide in virtually all environmental matrices, as well as in food, indoor samples, and human milk 5,7,15–18 .…”

“…Typically, GC and high‐performance liquid chromatography (HPLC) in combination with low‐ or high‐resolution mass spectrometry (HRMS) are used in CP analysis (Table S1 in Sprengel and Vetter 15 ). 3 Among the various instrumental setups, GC coupled with electron capture negative ion mass spectrometry (GC/ECNI‐MS) in selected ion monitoring (SIM) mode is still the most commonly used method for SCCP and MCCP analysis (Table S1 in Sprengel and Vetter 15 ). 6 Although GC/ECNI‐MS (low resolution) instruments are comparatively affordable, the required efforts are high 15 .…”

“…still the most commonly used method for SCCP and MCCP analysis (Table S1 in Sprengel and Vetter 15 ). 6 Although GC/ECNI-MS (low resolution) instruments are comparatively affordable, the required efforts are high.…”

“…Determined CP amounts were compared with an established comprehensive GC/ECNI-MS-SIM quantification method. 15 Comparative measurements included single chain-length CP standards, a technical CP product, and several edible oil samples with and without CPs.…”