Long-chain Chlorinated Paraffins Research Articles

Medium-chain chlorinated paraffins (MCCPs) induce renal cell aging and ferroptosis.

Medium-chained chlorinated paraffins (MCCPs) are a class of chlorinated derivatives of straight-chain n-alkanes with complex compositions, which are widely used in industry. The chlorinated paraffins (CPs) are divided into short chain chlorinated paraffins (SCCPs), medium chain chlorinated paraffins (MCCPs) and long chain chlorinated paraffins (LCCPs). SCCPs have been banned due to their severe bioaccumulation and biotoxicity. Therefore, MCCPs are used as a substitute for SCCPs. However, the toxicological data of MCCPs are still very limited. For this, we systematically investigated the toxicological impact of MCCPs on a renal cell model in the current study. Our work provides basic research data for analyzing the toxicological effects of MCCPs, suggesting that MCCPs should be restricted in their usage. A series of biochemical experiments was performed, including Western blot, indirect immunofluorescence assay, and ELISA was performed to analyze the toxicological effects of MCCPs. Two renal cell lines were used as a model for assessing the toxicological effects of MCCPs. Cell proliferation assays showed that MCCPs could inhibit the proliferation of kidney cells in a dose-dependent manner. Further studies showed that MCCPs induced ferroptosis in kidney cells by evaluating a series of ferroptosis marker molecules. Additionally, MCCPs induced inflammatory response and premature senescence in HEK293 and NRK-52E cells. Molecular mechanism experiments showed that ferroptosis induced by MCCPs emerged as a significant contributor to premature aging of kidney cells. The current study provides basic research data to analyze the toxicological effects of MCCPs and their toxicity mechanisms. It also provides a theoretical basis for the assessment of the potential ecological risk of MCCPs, as well as basic experimental data for the rational and standardized use of MCCPs.

Identification of Sulfur-Containing Chlorinated Paraffin Structural Analogues in Human Serum: Origination from Biotransformation or Bioaccumulation?

Chlorinated paraffins (CPs) are manufactured and used in high quantities and have diverse structural analogues. It is generally recognized that sulfur-containing structural analogues of CPs are mainly derived from sulfate-conjugated phase II metabolism. In this study, we non-targeted identified three classes of sulfur-containing CP structural analogues (CPs-S) in human serum, including 44 CP sulfates (CPs-SO4H/CPs-SO4H-OH), 14 chlorinated benzene sulfates (CBs-SO4H), and 19 CP sulfite esters (CPs-SO3/CPs-S2O6), which were generated during the production of commercial mixtures of CPs and, thus, bioaccumulated via environmental exposures. We first wrote a program to screen CPs-S, which were baseline-separated from CPs according to their polar functional groups. Then, mass spectral analyses of alkalization-acidification liquid-liquid extracts of serum samples and Orbitrap mass spectrometry analyses in the presence and absence of tetraphenylphosphonium chloride (Ph4PCl), respectively, were performed to determine the ionization forms ([M + Cl]- or [M - H]-) of CPs-S. The presence of fragment ions (SO4H-, SO3-, SO2Cl-, and HSO3-) revealed the structures of CPs-S, which were validated by their detections in commercial mixtures of CPs. The estimated total concentrations of CPs-S in the human serum samples were higher than the concentrations of medium- and long-chain CPs. The profiles of CPs-S in human serum were similar to those detected in CP commercial mixtures and rats exposed to the commercial mixtures, but CPs-S were not detected in human liver S9 fractions or rat tissues after exposure to CP standards. These results, together with the knowledge of the processes used to chemically synthesize CPs, demonstrate that CPs-S in humans originates from environmental bioaccumulation.

Characterization of short-, medium-, and long-chain chlorinated paraffins in Tibetan butter and implications for local human exposure

Since short-chain chlorinated paraffins (SCCPs) were severely restricted under the Stockholm Convention in 2017, a shift to the production of other chlorinated paraffin (CP) groups has occurred, particularly medium-chain (MCCPs) and long-chain CPs (LCCPs), although data on the latter are sparser in the literature. This study described the occurrence of three types of CPs in butter samples from six livestock milk sources across 15 sites in Tibet. The median levels of SCCPs, MCCPs, and LCCPs were 132, 456, and 13.2 ng/g lipid, respectively. The detection rate of 97.6% suggests that LCCPs can be transmitted to humans. Thus, all CPs, regardless of their chain length and degree of chlorination, should be treated with caution. The differences in concentration were mainly caused by dynamic wet deposition and thermodynamic cold-trapping effects across the different districts. The homolog pattern of CPs varied widely across livestock species, which was attributed to the diverse impacts of the physicochemical properties of the homologs, especially the heterogeneity in the uptake and transfer of CPs across different organisms. Under three different criteria, the health risks associated with the daily intake of SCCPs should not be neglected, especially considering other intake exposure pathways and the degradation of longer-carbon-chain monomers.

Application of Liquid- and Supercritical Fluid Chromatography Coupled with High-Resolution Mass Spectrometry for the Analysis of Short-, Medium-, and Long-Chain Chlorinated Paraffins in Dietary Supplements

Chlorinated paraffins (CPs) are an emerging and ubiquitous group of environmental pollutants associated with adverse effects on human health, including endocrine disruption and possible carcinogenicity. In this study, supercritical fluid chromatography (SFC) and ultrahigh-performance liquid chromatography (UHPLC)—both coupled with high-resolution mass spectrometry (HRMS)—methods for the analysis of short-, medium-, and long-chain CPs in fish oil-based dietary supplements were developed and validated at concentration levels of 0.6 and 3.0 μg/g lipid weight (lw). The recoveries were in the range of 80–96% and repeatabilities, expressed as relative standard deviations, were <19%. The limits of detection for the UHPLC–HRMS method (from 0.03 to 0.05 μg/g lw) were 5 to 10 times lower than those obtained by SFC–HRMS (from 0.13 to 0.50 μg/lw).

Homologue Composition of Technical Chlorinated Paraffins Used in Several Countries over the Last 50 Years─SCCPs Are Still Out There.

Chlorinated paraffins (CPs) are widely produced chemicals, with certain CP subgroups facing global restrictions due to their environmental dispersion, persistence, bioaccumulation, and toxicity. To evaluate the effectiveness of these international restrictions, we assessed the homologue group contribution and the mass fraction of short-chain CPs (SCCPs: C10-C13), medium-chain CPs (MCCPs: C14-C17), and long-chain CPs (LCCPs: ≥C18) in 36 technical CP mixtures used worldwide over the last 50 years. Using low-resolution mass spectrometry (LC-ESI-MS/MS), we quantified 74 CP homologue groups (C10Cl4-C20Cl10). Additionally, high-resolution mass spectrometry (LC-ESI-QTOF-MS) screening was employed to identify unresolved CP contents, covering 375 CP homologue groups (C6Cl4-C30Cl30). Overall, 1 sample was mainly composed of <C10-CPs, 10 of SCCPs, 13 of MCCPs, and 12 of LCCPs. Specific homologue group contributions and mass fractions of CP subgroups varied considerably. However, the predominance of C11Cl6- and C14Cl6-CP homologue groups was in good agreement with that of the dominant homologue groups in environmental matrices and manufactured products. SCCP yields are still high in some technical CP mixtures, and three technical CP mixtures currently produced failed the Stockholm Convention restrictions on SCCPs. This study sheds light on significant challenges in implementing international CP restrictions effectively.

Detection of trace chlorine pollutants in recycled pulp using gas chromatography-tandem mass spectrometry with response surface-optimized carbon structure online catalysis.

Chlorinated aromatics and alkanes are widely used for their flame retardancy, but they need to be monitored when used in recycled pulp. This paper reports the use of palladium acetate/activated carbon (Pa/Ac) activated by nitric acid as an online catalyst to determine chlorinated aromatics and chlorinated alkanes in recycled paper products using gas chromatography-tandem mass spectrometry (GC-MS/MS), which significantly improves the sensitivity of the method and remarkably lowers the detection limits. The Pa/Ac catalyst was prepared using a self-made catalytic device and used as key to the online catalytic conversion of target chlorinated aromatic hydrocarbons and chlorinated alkanes for GC-MS/MS analysis. The response surface model was used to optimize catalytic conditions. Then GC-MS/MS in the multireaction monitoring mode with online catalysis was applied for the analysis of polychlorinated biphenyls, polychlorinated terphenyls, polychlorinated naphthalene, and chlorinated paraffins (CP) in recycled paper products. Compared with traditional methods, the Pa/Ac catalyst can transform chlorinated aromatic hydrocarbons into aromatic hydrocarbons through dechlorination hydrogenation, thus lowering the detection limit of the GC-MS/MS method significantly. It can transform paraffin chloride into the corresponding alkane to better distinguish short-chain, medium-chain, or long-chain CPs. Online catalytic conversion significantly improved the sensitivity and reproducibility (88.7%-113.1%) of the method. Tissue samples with various concentration levels of chlorinated aromatics and chlorinated alkanes were tested. The linearity range of the reduced target compounds in the reduction product solution was 0.02-1.00 μg/ml (R2 >0.995). The quantitative detection limit was 0.03-0.05 μg/kg, and relative standard deviation was less than 6.9%. This study was the first to introduce the Pa/Ac catalytic device as an online catalytic unit in the determination of chlorinated aromatics and chlorinated alkanes using the GC-MS/MS method. The target compounds were converted into alkanes and aromatic hydrocarbons with unchanged carbon structures, and the method could achieve a low detection limit with no need for high-end methods such as GC-chemical ionization ion source (CI)-MS or high-resolution mass spectrometry. These methods are suitable for the determination of chlorine pollutants in recycled paper and its raw materials.

An international investigation of chlorinated paraffin concentrations and homologue distributions in indoor dust

In this study, very short-, short-, medium-, and long-chain chlorinated paraffins (vSCCPs, SCCPs, MCCPs and LCCPs, respectively) were measured in 40 indoor dust samples from four countries including Japan (n = 10), Australia (n = 10), Colombia (n = 10) and Thailand (n = 10). Homologues of the chemical formula CxH(2x+2−y)Cly ranging C6-36 and Cl3-30 were analysed using liquid chromatography coupled to Orbitrap high resolution mass spectrometry (LC-Orbitrap-HRMS) and integrated using novel custom-built CP-Seeker software. CPs were detected in all dust samples with MCCPs the dominant homologue group in all countries. Overall median ∑SCCP, ∑MCCP and ∑LCCP (C18-20) concentrations determined in dust samples were 30 μg/g (range; 4.0–290 μg/g), 65 μg/g (range; 6.9–540 μg/g) and 8.6 μg/g (range; <1.0–230 μg/g), respectively. Of the quantified CP classes, overall concentrations were generally highest in the samples from Thailand and Colombia, followed by Australia and Japan. vSCCPs with C≤9 were detected in dust from each country with an overall frequency of 48%, while LCCPs (C21-36) were present in 100% of samples. Estimated daily intakes (EDIs) calculated for SCCPs and MCCPs relating to ingestion of contaminated indoor dust were considered not to represent health risks based on currently available toxicological data using the margin of exposure (MOE) approach. To the authors’ knowledge, this study provides the first data on CPs in indoor dust from Japan, Colombia and Thailand, and is among the first reports of vSCCPs in indoor dust, globally. These findings indicate that further toxicological data and the availability of appropriate analytical standards are needed to evaluate the potential for negative health outcomes deriving from exposure to vSCCPs and LCCPs.

(096) Chronic Oral Exposure to Short Chain - Chlorinated Paraffins Induced Testicular Toxicity by Promoting NRF2-mediated Oxidative Stress

Abstract Introduction Chlorinated paraffins (CPs) are important additives in a variety of chemical processing. Based on the lengths of the carbon chains, CPs are classified into short-chain CPs (SCCPs, C10-13), medium-chain CPs (MCCPs, C14-17) and long-chain CPs (LCCPs, C18-30) with the chlorine content ranging from 30%-70%. SCCPs were listed in the persistent organic pollutants (POPs) by Stockholm Convention due to its toxicity, bioaccumulation potential, long range transport potential and environmental persistence. Numerous studies have analyzed the toxicities of SCCPs in various organisms, with the toxic effects including lethality and carcinogenicity, developmental toxicity, endocrine disrupting effect and immunomodulatory effect. Objectives As a widespread environmental contaminant, short chain chlorinated paraffins (SCCPs) has attracted great attention. However, the toxicity of SCCPs on male reproductive system remains ambiguous. In this study, we investigated the toxic effects of SCCPs on testis. Methods We treated mice with 1,10 or 100 mg/kg bm/d SCCPs by gavage once a day for 35 days. The tissues and blood samples were collected after treatment. The weight of mice and testes were measured. The organ index is the body weight divided by the weight of the testis. The left testes were used for protein extraction, RNA extraction and measurement of SOD, CAT, GST and MDA. The left epididymis was used for analysis of sperm parameters. The right testis and epididymis were fixed in Bouin’s solution for H&amp;E and TUNEL staining. GC2 cell (mouse spermatocyte) treated with SCCPs was used to examined the cell viability by CCK8 kits. Cellular ROS generation was evaluated by 2',7'Dichlorodihydrofluorescein diacetate (DCFH-DA). We used Apoptosis Detection Kit to detect the cell apoptosis by dual staining cells with Annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI). Results SCCPs resulted in disorderly arranged seminiferous epithelium and increased apoptotic cells in testes. Both in vivo and in vitro experiments indicated that the oxidative stress was induced after SCCPs exposure, and dysfunction of nuclear factor erythroid-related factor (NRF2) signaling pathway played a role in this process. Moreover, resveratrol, an NRF2 activator, could alleviate the damage of SCCPs on spermatogenetic cells in vitro. Our study indicated that oxidative stress is the key point for explaining the testicular toxicity caused by SCCPs, and NRF2 could be used as a potential target for clinical treatment to alleviate the reproductive toxicity induced by SCCPs. Conclusions Our study is the first to evaluate the toxic effects of SCCPs on male reproductive system, which is associated with overproduction of ROS. This study also indicates that NRF2/ARE pathway plays the vital role in the toxic effects of SCCPs in spermatogenesis, thus providing a target for the prophylaxis and treatment. Disclosure No

Characterization of short-, medium- and long-chain chlorinated paraffins in ambient PM2.5 from the Pearl River Delta, China

Research on the environmental occurrence of long-chain chlorinated paraffins (LCCPs) in ambient fine particulate matter (PM2.5) is still scarce. In the present study, short-chain chlorinated paraffins (SCCPs), medium-chain chlorinated paraffins (MCCPs) and LCCPs were simultaneously quantified and profiled in PM2.5 samples collected from 96 primary or secondary schools in the Pearl River Delta of South China. SCCPs, MCCPs and LCCPs were detected in higher than 90% samples with concentrations in the range of 0.832–109, 1.02–110, and 0.173–17.4 ng/m3, respectively. The dominant congener groups of SCCPs, MCCPs and LCCPs were C13Cl6-8, C14Cl7-8, and C18Cl7-9, respectively. The concentrations of SCCPs and MCCPs were higher in summer than in winter, while an opposite seasonal trend was observed for LCCPs. Principal components analysis showed there were seasonal variations in the congener group patterns with C13Cl6-7 and C14Cl7 more abundant in summer than in winter. Concentrations of CPs also exhibited slight spatial variations. Exposure risk assessment based on different age groups suggested exposure to PM2.5-associated CPs would not pose significant health risk. The present study expands the existing knowledge of CPs contamination in atmospheric environment.

Dietary Intake Contributed the Most to Chlorinated Paraffin Body Burden in a Norwegian Cohort.

Determining the major human exposure pathways is a prerequisite for the development of effective management strategies for environmental pollutants such as chlorinated paraffins (CPs). As a first step, the internal and external exposure to CPs were quantified for a well-defined human cohort. CPs in participants' plasma and diet samples were analyzed in the present study, and previous results on paired air, dust, and hand wipe samples were used for the total exposure assessment. Both one compartment pharmacokinetic modeling and forensic fingerprinting indicate that dietary intake contributed the most to body burden of CPs in this cohort, contributing a median of 60-88% of the total daily intakes. The contribution from dust ingestion and dermal exposure was greater for the intake of long-chain CPs (LCCPs) than short-chain CPs (SCCPs), while the contribution from inhalation was greater for the intake of SCCPs than medium-chain CPs (MCCPs) and LCCPs. Significantly higher concentrations of SCCPs and MCCPs were observed in diets containing butter and eggs, respectively (p < 0.05). Additionally, other exposure sources were correlated to plasma levels of CPs, including residence construction parameters such as the construction year (p < 0.05). This human exposure to CPs is not a local case. From a global perspective, there are major knowledge gaps in biomonitoring and exposure data for CPs from regions other than China and European countries.

Seasonal variation of short-, medium- and long-chain chlorinated paraffin distribution in Belgian indoor dust

Chlorinated paraffins (CPs) are high production volume plasticizers and flame retardants, which have exhibited bioaccumulative and toxic properties. CPs may be released from treated consumer goods and bind with indoor dust, leading to human exposure via unintentional dust ingestion. In this study, the concentrations and homologue distribution of CPs were measured in 50 indoor dust samples collected in paired winter and summer sampling campaigns from 25 homes in Flanders, Belgium. Short-, medium- and long-chain CPs (SCCPs (C10-13), MCCPs (C14-17) and LCCPs (C18-20), respectively) were each detected in all Belgian indoor dust samples with overall median concentrations of 6.1 µg/g (range 0.61 to 120 µg/g), 45 µg/g (range 4.5 to 520 µg/g) and 4.5 µg/g (range 0.3 to 50 µg/g), respectively. Concentrations were significantly higher in the winter samples than summer for each of the three groups (p < 0.05). LCCPs homologues ranging from C21-32 were also detected in dust samples and accounted for approximately half of the LCCP relative abundance based on instrumental peak area, although a lack of appropriate analytical standards prevented quantification of these homologues. While clear sources of CP contamination in dust could not be identified, significant associations between concentrations of ∑SCCPs, ∑MCCPs and ∑LCCPs (C18-20) (p < 0.05) suggested the combined application within materials or products in homes. Based on typical exposure scenarios, estimated daily intake of ∑CPs (C10-20) for adults and toddlers were 14 and 270 ng/kg bw/day, respectively, though margin of exposure assessments for SCCPs and MCCPs indicated that adverse health effects were unlikely for all exposure scenarios. This study presents the first evidence of seasonal variation in the levels and distribution for each of the SCCP, MCCP and LCCP classes in indoor dust and highlights the urgent need for appropriate analytical standards for LCCP quantification.

Influence of Sediment Dredging on the Distribution of Chlorinated Paraffin

To study the influence of dredged sediment transportation on the distribution of short-chain chlorinated paraffins (SCCPs, C10-13), medium-chain chlorinated paraffins (MCCPs, C13-17), and long-chain chlorinated paraffins (LCCPs, C18-28), 62 surficial sediment samples were collected from the Huangpu River and the Shanghai offshore areas, East China. A high-performance liquid chromatograph coupled with a quadrupole time-of-flight mass spectrometry system (HPLC-QTOF MS) was employed to measure CPs. The concentrations of CPs in sediment samples ranged from 8.76 to 1270.7 ng g−1 for SCCPs, from 22.03 to 1730.78 ng g−1 for MCCPs, and from undetected (ND) to 236.86 ng g−1 for LCCPs. The concentrations were lower than those that can be toxic to organisms. Furthermore, the influence of sediment dredging activity on the distribution of CPs was also investigated. The concentrations of CPs in sediment discarding areas were significantly higher than those in the surrounding areas, but this result is consistent with the concentrations in the Huangpu River sediments where CPs originated. Also, the SCCP congener group in the discarding area was similar to that in the Huangpu River. These findings indicated that CPs exhibited lower migration in the discarding area and had limited environmental impacts.

QuEChERS-based extraction and two-dimensional liquid chromatography-high resolution mass spectrometry for the determination of long chain chlorinated paraffins in sediments

In this study, a method was established for the analysis of long-chain chlorinated paraffins (LCCPs) in sediment based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and two-dimensional liquid chromatography-Orbitrap high resolution mass spectrometry (2DLCOrbitrap HRMS). Compared with other reported methods, this method greatly reduces sample preparation time (2 h) and solvent consumption. The QuEChERS extraction method presented satisfactory recoveries, 90.5–95.2, 84.7–86.6, and 81.4–83.4% of 5, 50, and 200 ng/g LCCPs with 49% Cl spiked into sediments. Meanwhile, no matrix effects were found in the LCCPs analysis after online purification by the 2DLC system. With the current commercial LCCP standards and a mixture of three chlorinated paraffins (CPs) industrial products, a suspect screening strategy was established and accurate identification of LCCPs (including vLCCPs, which carbon chain length greater than 20) under the plight that the reference standards for vLCCPs are currently unavailable. A total of 21 C18–20-LCCP and 22 vLCCP congeners were identified in sediment samples collected from Dongting Lake, China. The total concentrations of LCCPs in six sediment samples ranged from 1.69 to 18.0 ng/g (median 6.66 ng/g) and was dominated by C18 groups (mean, 28.8%), C19 groups (mean, 19.1%) and C21 groups (mean, 16.9%). Taken together, the successful application of this method to analyze sediment samples shows great potential for the analysis of LCCPs in environmental samples in future studies.

Evaluating the dynamic distribution process and potential exposure risk of chlorinated paraffins in indoor environments of Beijing, China

Chlorinated paraffins (CPs) are typical semi-volatile chemicals (SVOCs) that have been used in copious quantities in indoor material additives. SVOCs distribute dynamically between the gas phase and various condensate phases, especially organic films. Investigating the dynamic behaviors of existing CPs in indoor environments is necessary for understanding their potential risk to humans from indoor exposure. We investigate the distribution profiles of CPs in both gas phase and organic films in indoor environments of residential buildings in Beijing, China. The concentrations of CPs were in the range of 32.21–1447 ng/m3 in indoor air and in the range of 42.30–431.1 μg/m2 and in organic films. Cooking frequency was identified as a key factor that affected the distribution profiles of CPs. Furthermore, a film/gas partitioning model was constructed to explore the transportation and fate of CPs. Interestingly, a re-emission phenomenon from organic films was observed for chemical groups with lower log Koa components, and, importantly, their residue levels in indoor air were well predicted. The estimated exposure risk of CPs in indoor environment was obtained. For the first time, these results produced convincing evidence that the co-exposure risk of short-chain CPs (SCCPs), medium-chain CPs (MCCPs), and long-chain CPs (LCCPs) in indoor air could be further increased by film/gas distribution properties, which is relevant for performing risk assessments of exposure to these SVOCs in indoor environments.

Application of Liquid- and Supercritical Fluid Chromatography Coupled with High-Resolution Mass Spectrometry for the Analysis of Short-, Medium-, and Long-Chain Chlorinated Paraffins in Dietary Supplements

Chlorinated paraffins (CPs) are an emerging and ubiquitous group of environmental pollutants associated with adverse effects on human health, including endocrine disruption and possible carcinogenicity. In this study, supercritical fluid chromatography (SFC) and ultrahigh-performance liquid chromatography (UHPLC) — both coupled with high-resolution mass spectrometry (HRMS) — methods for the analysis of short-, medium-, and long-chain CPs in fish oil-based dietary supplements were developed and validated at concentration levels of 0.6 and 3.0 µg/g lipid weight (lw). The recoveries were in the range of 80–96% and repeatabilities, expressed as relative standard deviations, were &lt;19%. The limits of detection for the UHPLC–HRMS method (from 0.03 to 0.05 µg/g lw) were 5 to 10 times lower than those obtained by SFC–HRMS (from 0.13 to 0.50 µg/lw).

Exposure to short-, medium-, and long-chain chlorinated paraffins for infant via cow infant formula, goat infant formula and baby food

Dietary exposure is an important pathway for many pollutants from external exposure to human beings. In this study, we investigated the exposure to short-chain chlorinated paraffins (SCCPs), medium-chain chlorinated paraffins (MCCPs) and long-chain chlorinated paraffins (LCCPs), which are a class of industrial compounds that are of significant concern, in different infant foods (cow infant formula, goat infant formula and baby food are collectively called infant food in this study) in Chinese market. The concentrations of ∑SCCPs, ∑MCCPs and ∑LCCPs in infant foods were in the ranges of 6.22–273 ng/g, 13.1–2020 ng/g and 0.80–1280 ng/g, respectively. Especially, for the first time, we found that the proportion of ∑LCCPs (22.0%) in goat infant formula is almost equivalent to that of ∑SCCPs (25.0%), implying that LCCPs should also be further concerned since the related information is very scarce. There were differences between CP profiles among imported cow infant formula and Chinese cow infant formula due to the different sources of CPs to the infant formula. Imported infant foods were characterized by higher proportion of SCCPs, while Chinese infant foods were characterized by higher proportion on LCCPs. Margin of exposure results demonstrated that there was no significant health concern for the infant, but that large variation of CP concentrations and excessive feeding in practice may cause potential health threats to the infant. LCCPs were detected in all infant food samples, and to our knowledge, this is the first report of LCCPs in cow infant formula, goat infant formula and baby food. This study could provide important data of infant exposure to CPs, especially, LCCPs.

Determination of Long Chain Chlorinated Paraffins in Soils and Sediments by High-Performance Liquid Chromatography (HPLC) High Resolution Mass Spectrometry (HR-MS)

Long-chain chlorinated paraffins (LCCPs) have gained attention due to their bioaccumulation and toxicity. However, their determination is hindered by low vapor pressure and limited elution from gas chromatography columns. In this study, ammonium acetate (CH3COONH4) was employed as the mobile phase additive and directly applied to high-performance liquid chromatography coupled with Orbitrap high resolution mass spectrometry (HPLC-Orbitrap HRMS). Acetate adducts [M + CH3COO]– were selected for quantifying the LCCPs. The mass spectral parameters, such as the radio frequency lens percentage, vaporizer, ion transfer tube temperature, and spray voltage, were optimized. A new analytical strategy for LCCPs was established based on HPLC-Orbitrap HRMS. The accuracy, limits of detection (LOD), and limits of quantification (LOQ) were equal to 94.8% to 109.4%, 7.9 to 16.0 pg/μL, and 26.3 to 53.3 pg/μL for the LCCPs, respectively. The linear range was between 0.04 and 10.0 ng/μL with R2 values of 0.999 for the LCCPs. The relative standard deviations for intra-day and inter-day precision were from 0.5% to 3.3% and from 0.7% to 7.2%, respectively. This method was validated using 20 sediment and soil samples. For the first time, highly chlorinated (Cl>15) and longer carbon chain length (C>36) homologues of LCCPs were observed in soil. The method was suitable for determining LCCPs while avoiding modified instruments and eliminating the incompatibility of CH2Cl2 with the HPLC mobile phase. Further measurements are required of sediment, soil, and air to better characterize LCCPs in the environment.

Are fish oil-based dietary supplements a significant source of exposure to chlorinated paraffins?

Chlorinated paraffins (CPs) are an emerging group of environmental pollutants associated with adverse effects on human health (such as endocrine disruption and possible carcinogenicity). CPs are classified into several groups: short- (SCCPs), medium- (MCCPs) and long-chain chlorinated paraffins (LCCPs). In this study, CPs were determined in fish oil-based omega-3 dietary supplements (DS) representing widely consumed products that might be contaminated with various lipophilic contaminants including CPs. The CPs were isolated from DS (n = 85) by solid phase extraction. The SCCPs and MCCPs were determined by gas chromatography coupled with high-resolution mass spectrometry operated in a negative chemical ionisation mode. The LCCPs (up to C21) were screened using supercritical fluid chromatography coupled with high-resolution mass spectrometry with electrospray ionisation operated in negative mode. The CP concentrations varied from <0.01 to 56.48 μg/g fat for SCCPs (median 0.12 μg/g fat; limit of quantification, LOQ, for SCCPs was exceeded in 51 out of 85 samples) and from <0.03–89.08 μg/g fat for MCCPs (median 0.26 μg/g fat; LOQ for MCCPs was exceeded in 66 out of 85 samples), respectively. The LCCPs were not quantified in this study, nevertheless their limit of detection (0.5 μg/g fat) was exceeded in 7 out of 85 samples. Due to high levels of CPs, DS might pose as a significant source of CPs exposure to some population groups.

Evidence of complementarity between targeted and non-targeted analysis based on liquid and gas-phase chromatography coupled to mass spectrometry for screening halogenated persistent organic pollutants in environmental matrices

This study explored the complementarity between targeted (TS) and non-targeted screening (NTS) based on liquid and gas-phase chromatography coupled to (high-resolution) mass spectrometry (LC-/GC-(HR)MS) for the comprehensive characterization of organohalogen fingerprints within a set of Lake Ontario lake trout samples. The concentrations of 86 legacy, emerging and novel halogenated compounds (HCs), were determined through 4 TS approaches involving no less than 6 hyphenated systems. In parallel, an innovative NTS strategy, involving both LC and GC-Q-Orbitrap, was implemented to specifically highlight halogenated signals. Non-targeted HRMS data were processed under the HaloSeeker software based on Cl and Br isotopic ratio and mass defect to extend the screening to unsuspected and unknown HCs. A total of 195 halogenated mass spectral features were characterized in the Lake Ontario lake trout, including well known HCs (PCBs, PBDEs, PBBs, DDT and their degradation products), emerging HCs (novel brominated flame retardants, short-, medium- and long-chain chlorinated paraffins) or suggested molecular formula (mainly polychlorinated ones). Among the 122 HCs highlighted by TS, only 21 were identified by NTS. These results fueled a discussion on the potential and limitations of both approaches, and the current position of NTS within environmental and health monitoring programs.

Short- and medium-chain chlorinated paraffins in commercial complementary baby food produced in different European countries: Occurrence, congener group profiles, portion-based dietary intake, and risk assessment

This study was performed to evaluate the presence of chlorinated paraffins (CPs) in complementary baby food from different European countries, to assess portion-based dietary intake of CPs, and to characterize possible risks to children arising from CPs uptake. In total, 86 baby food samples from 22 countries were grouped into eight food-type categories considering the WHO classification. In six out of eight sample categories, predominance of medium-chain CPs (MCCPs) concentrations over short-chain CPs (SCCPs) was observed and, contrary to expectations, samples that contained ingredients of animal origin (e.g., meat or fish) did not display elevated CPs levels. The median ∑CPs concentrations for selected sample categories ranged from 0.8 ng g−1 for desert to 2.8 ng g−1 found in dry cereal and porridge subgroups, while the highest CPs concentration of 387 ng g−1 was observed in dry porridge. Among the selected groups of baby foods, portion-based intake of ∑CPs varied from 1.0 to 43.6 ng kg−1 body weight (b.w.) while exposure estimations indicated that portion-based dietary exposure through consumption of complementary baby food was the highest for infants aged 3–12 months due to the lower body weight. The risk characterization according to the European Food Safety Authority (EFSA) approach showed that the margin of exposure (MOE) figures higher than the critical value for ∑CPs, indicating that the dietary exposures through consumption of complementary baby food are unlikely to be of significant health concern for children. However, it should be pointed out that the performed risk assessment covered only SCCPs and MCCPs, while the occurrence of other groups from CPs and CPs related compounds (e.g., very short-chain CPs, chlorinated alkenes, or long-chain CPs (LCCPs)) was not addressed.