Introduction
Cleaning agent, lubricant and chlorinated paraffin-containing lubricants for degreasing and cleaning; especially effective for difficult-to-clean high-viscosity metal processing oils. Chlorinated paraffin, colorless and transparent (first grade), has low concentration, comprehensive use, fast oiling speed and good oil removal effect.
Stainless steel chemicals: supplies for rust removal, pickling, passivation, cleaning, polishing, etching, protection, lubrication, coloring, degreasing, blackening, etc. Copper chemicals: supplies for oil removal, rust removal, polishing, passivation, antioxidant, anti-discoloration, coloring, blackening, protection, etching, lubrication, etc.
Steel chemicals: supplies for degreasing, cleaning, lubrication, rust removal, rust prevention, anti-corrosion, phosphating, blackening, polishing, protection, etc. Aluminum chemicals: supplies for oil removal, rust removal, coloring, passivation, polishing, etching, anodizing, sealing, etc.
Abstract
chlorinated paraffin (CPs), as technical mixtures of polychlorinated alkanes (PCAs), are ubiquitous in the environment. CPs tend to behave in a similar way to persistent organic pollutants (POPs), leading several countries to impose regulations on the use of CPs.
In this article, we review the literature on the properties of CPs, the current analytical tools available to determine CPs in various types of environmental matrices, and concentrations found in the environment. In particular, concentrations of CPs in environmental compartments including air, water, sediments, biota, human food products and human tissues are summarized. Priorities for future research are:
improvements in analytical methodologies (reducing the complexity of the analysis, producing reference materials and performing interlaboratory studies); determining background levels of chlorinated paraffins in the environment and human populations (this question should be answered using quality assured analytical tools allowing the intercomparison of data); and investigating the sources of CPs to the environment and to humans.
1. Understanding inter-individual variability in short-chain chlorinated paraffin concentrations in human blood
Abstract
Chlorinated paraffins (CPs), particularly short-chain CPs (SCCPs), have been reported in human blood with high detection frequency and often high variation among individuals. However, factors associated with and their contributions to inter-individual variability in SCCP concentrations in human blood have not been assessed.
In this study, we first measured SCCP concentrations in 57 human blood samples collected from individuals living in the same vicinity in China. We then used the PROduction-To-Exposure model to investigate the impacts of variations in sociodemographic data, biotransformation rates, dietary patterns, and indoor contamination on inter-individual variability in SCCP concentrations in human blood.
Measured ∑SCCP concentrations varied by a factor of 10 among individuals with values ranging from 122 to 1230 ng/g, wet weight. Model results show that age, sex, body weight, and dietary composition played a minor role in causing variability in ∑SCCP concentrations in human blood given that modeled ∑SCCP concentrations ranged over a factor of 2 – 3 correlated to the variations of these factors.
In contrast, variations in the modeled ΣSCCP concentrations increased to factors of 6 and 8 when variability in biotransformation rates and indoor contamination were considered, respectively, indicating these two factors could be the most influential on inter-individual variability in SCCP concentrations in human blood.
We estimated the DBDPE emission in each of the five regions using the “Technosphere” module nested in the PROTEX model (Li and Wania, 2016;Li et al., 2018a), which applies the substance flow analysis method. The model has been widely used for quantifying the emission of chemicals in products from various lifecycle stages (Li et al., 2018a(Li et al., , 2018bNiu et al., 2022), and is described in detail by Li and Wania (2016). Briefly, we considered the DBDPE emissions during the whole lifecycle, i.e., production, processing, use, and disposal of products containing DBDPE. …
The module requires three types of input parameters: (i) the estimated temporal variance of DBDPE emissions (output through the “Technosphere” model); the chemical properties of DBDPE, which include the partitioning properties (e.g., air-water partition coefficient) and reaction properties in environments and organisms (e.g., the reaction rate constant in sediment); and (iii) environmental parameters (e.g., environmental temperature and size of the urban area) for the five regions.
We selected the chemical properties of DBDPE based on the best practice recommend by Li et al. (2022) and obtained the environmental parameters from the National Bureau of Statistics of China (NBSC, 2022). The detailed input parameters are given in Tables S7 and S8.
2. Photochemical Degradation of Short-Chain Chlorinated Paraffins in Aqueous Solution by Hydrated Electrons and Hydroxyl Radicals
Abstract and Figures
Short-chain chlorinated paraffins (SCCPs) are a complex mixture of polychlorinated alkanes (C10-C13, chlorine content 40-70%), and have been categorized as persistent organic pollutants. However, there are knowledge gaps about their environmental degradation, particularly the effectiveness and mechanism of photochemical degradation in surface waters.
Photochemically-produced hydrated electrons (e-(aq)) have been shown to degrade highly chlorinated compounds in environmentally-relevant conditions more effectively than hydroxyl radicals (·OH), which can degrade a wide range of organic pollutants. This study aimed to evaluate the potential for e-(aq) and ·OH to degrade SCCPs. To this end, the degradation of SCCP model compounds was investigated under laboratory conditions that photochemically produced e-(aq) or ·OH. Resulting SCCP degradation rate constants for e-(aq) were on the same order of magnitude as well-known chlorinated pesticides.
Experiments in the presence of ·OH yielded similar or higher second-order rate constants. Trends in e-(aq) and ·OH SCCP model compounds degradation rate constants of the investigated SCCPs were consistent with that of other chlorinated compounds, with higher chlorine content producing in higher rate constants for e-(aq) and lower for ·OH. Above a chlorine:carbon ratio of approximately 0.6, the e-(aq) second-order rate constants were higher than rate constants for ·OH reactions. Results of this study furthermore suggest that SCCPs are likely susceptible to photochemical degradation in sunlit surface waters, facilitated by dissolved organic matter that can produce e-(aq) and ·OH when irradiated.
3. Green chemistry: its opportunities and challenges in colouration and chemical finishing of textiles
Green chemistry is a discipline that can be applied across various stages in the production and processing of textiles. This article attempts to study the varied applications of green chemistry in the textile industry and to evaluate the areas where one can deploy its principles and review the need for and importance of switching to environmentally friendlier practices. The review sets its ground by discussing the needs of green chemistry and its utilization in textile colouration and a few prominent textile finishing segments.
Different applications of green chemistry in textiles are discussed elaborately, especially in the field of textile colouration, and a few important classes of finishes like antimicrobial, flame retardancy, water repellent and crease-resistant finishes (vis-à-vis conventional finishing chemicals). The existing chemicals and their toxicological hazards are discussed, and hence there is an utmost importance of sustainable chemistry. The latest trends in the manufacture of sustainable chemicals to endow the different finishes are also discussed in the subsequent sections.
The applications of green chemistry are promising, yet challenging and different future perspectives are highlighted at the concluding part of this review.
4. Occurrence, congener patterns, and potential ecological risk of chlorinated paraffins in sediments of Yangtze River Estuary and adjacent East China Sea
Abstract and Figures
Chlorinated paraffins (CPs) are high production volume chemicals with immense scientific research interest due to their wide distribution, persistence, toxicity, and bioaccumulation potential. In this study, 87 surface sediments were collected from the Yangtze River Estuary (YRE) and the adjacent East China Sea (ECS).
We investigated the concentrations, spatial distribution, and composition profiles of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) using ultra-high-performance liquid chromatography coupled with Orbitrap Fusion Tribrid mass spectrometry. The sedimentary concentrations of SCCPs and MCCPs ranged from 2.85 to 94.7 ng·g-1 (median 13.7 ng·g-1) and 3.33 to 77.8 ng·g-1 (median 13.3 ng·g-1), respectively. Higher CP concentrations were found in YRE sediments.
The values decreased away from the location, implying a direct influence of the Yangtze River. The SCCP concentrations were higher than those of MCCPs in most sediment samples. Overall, the predominant homologs were C13Cl5-7 and C14Cl6-8 for MCCPs and SCCPs, respectively. Overall, the sediment-dwelling organisms in the region are susceptible to low ecological risks.
5. A reference material (NMIJ RM 4076-a) for the determination of short-chain chlorinated paraffins
Abstract and Figures
Chlorinated paraffins are primary industrial chemical products used for metalworking fluids and flame retardants. However, short-chain chlorinated paraffins (SCCPs) are registered in Annex A of the Stockholm Convention on Persistent Organic Pollutants. Therefore, since an accurate quantitative determination of SCCPs is crucial to monitor the level of pollution, analysis quality assurance with reference materials is needed.
In this study, a reference material (RM), NMIJ RM 4076-a, was developed by the National Metrology Institute of Japan at the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) for the quantification of SCCPs. We determined the mass fraction of SCCPs by subtracting the impurities quantified using the mass-balance method, a combination of gas chromatography-flame ionization detection, Karl Fischer titrations, headspace-gas chromatography-mass spectrometry, and thermal gravimetric analysis.
The mass fraction value of NMIJ RM 4076-a was concluded to be 0.9996 kg/kg. The standard uncertainty of this mass fraction was evaluated on the basis of the mass-balance method, the sample homogeneity, and stability obtained using the above analytical techniques. Accordingly, the expanded uncertainty estimated using a coverage factor of k = 2 was found to be 0.0013 kg/kg. The mass fraction of chlorine and the homologue compositional ratios are also given for this RM as supplementary technical information.
This RM is expected to be applicable for use in the calibration of instruments, or for checking the validity of analytical methods or instruments for estimating the comparability of SCCP analyses.
6. Medium-chain chlorinated paraffins (MCCPs) induce renal cell aging and ferroptosis
Abstract
Purpose: 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.
Method: A series of biochemical experiments was performed, including Western blot, indirect immunofluorescence assay, and ELISA was performed to analyze the toxicological effects of MCCPs.
Results: 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.
Conclusion: 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.
7. Bee colonies map the short-and medium-chain chlorinated paraffin contamination from the apiary environment
Abstract
Chlorinated paraffins (CPs) are industrial chemicals that have potential adverse effects in the environment and on human health. This study investigated CPs in apiary environment, honeybees, and bee products from two rural areas of Beijing, China.
The median concentrations of short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) were 22 and 1.6 ng/m 3 in the ambient air, 1350 and 708 ng/g dry mass (dw) in bees, 1050 and 427 ng/g dw in flowers, 37 and 54 ng/g in honey, 78 and 53 ng/g dw in bee pollen, 36 and 30 ng/g dw in soil, and 293 and 319 ng/g dw in bee wax. C 10 Cl 6-7 and C 14 Cl 7-8 dominated SCCPs and MCCPs in these samples, respectively.
The concentrations and distributions of CPs in samples from apiaries located in the two regions varied. Long-range transportation of air masses was identified as an important source of CPs in apiaries. A close relationship between CPs in bees and the apiary environment indicated that bees could act as bioindicators for CP contamination in the environment. A human health risk assessment found that there were low risks for adults and children exposed to CPs through consumption of honey and pollen from the studied regions.
8. An analytical method for chlorinated paraffins and their determination in soil samples
Abstract and Figures
Short chain chlorinated paraffins (SCCPs) are possibly persistent organic pollutants (POPs), and are candidate POPs of the Stockholm Convention. In this study, three quantitative methods for analyzing CPs were compared using a gas chromatograph-electron capture detector (GC-ECD), gas chromatograph-electron capture negative ion low resolution mass spectrometry (GC-ECNI-LRMS) and gas chromatograph-electron ionization tandem mass spectrometry (GC-EI-MS2).
A quantitative method for the analysis of total CPs in soil samples was established. The environmental levels of CPs in an e-waste dismantling area in China were evaluated. Keywordschlorinated paraffins-short chain chlorinated paraffins-e-waste dismantling areas.
9. An analytical method for chlorinated paraffins and their determination in soil samples
Short chain chlorinated paraffins (SCCPs) are possibly persistent organic pollutants (POPs), and are candidate POPs of the
Stockholm Convention. In this study, three quantitative methods for analyzing CPs were compared using a gas chromato-
graph-electron capture detector (GC-ECD), gas chromatograph-electron capture negative ion low resolution mass spectrometry
(GC-ECNI-LRMS) and gas chromatograph-electron ionization tandem mass spectrometry (GC-EI-MS). A quantitative method
for the analysis of total CPs in soil samples was established. The environmental levels of CPs in an e-waste dismantling area in
China were evaluated
Materials and methods
1.1 Sampling sites and samples collection
YUAN Bo, et al. Chinese Sci Bull August (2010) Vol.55 No.22 2397
mental matrices, including river water, sediment, soil, biota
and human milk from different countries and regions, as
well as in the atmosphere of remote non-industrial areas and
high-latitude polar regions [11–16].
As candidate POPs reviewed by the POP review com-
mittee (POPRC) of the Stockholm Convention (SC), the
SCCPs proposal has been evaluated against the criteria of
Annex D of SC by POPRC in 2007. Comparatively limited
work has been carried out regarding the distribution, pollu-
tion characteristics, and environmental fate of SCCPs and
MCCPs in China, although CPs production and usage are
large [17,18].
This work presents different quantitative methods for the
determination of SCCPs and MCCPs using GC-ECD, GC-
ECNI-LRMS and GC-EI-MS
. A pre-treatment and in-
strumental method for analyzing the total CPs in soil was
established. This method was utilized to preliminarily
evaluate the pollution levels of CPs in an e-waste disman-
tling area.
1.2 Materials, standards and reagents
Cyclohexane, dichloromethane (DCM), n-hexane (nHex),
toluene and acetone for residue analysis were obtained from
Fisher (Hampton, NH). Sulfuric acid, hydrochloric acid and
anhydrous sodium sulfate were all guaranteed reagents.
Copper powder (63 μm) was washed in hydrochloric acid,
and was cleaned by deionized water and acetone before use.
Silica gel (0.063–0.100 mm) and Florisil (60–100 mesh)
were obtained from Merck (Whitehouse Station, NJ) and
activated at 550°C for 12 h. Anhydrous sodium sulfate was
heated to 600°C in a muffle furnace for 6 h.
Reference SCCP (chlorine contents of 51.5%, 55.5%,
63.0%), MCCP (chlorine contents of 52.0% and 57.0%) and
LCCP (C 22, chlorine contents of 72.1%) with concentra-
tions of 100 ng μL.
1.3 Instruments
GC-ECD measurements were performed using a 6890GC
with a DB-5 column (30-m length, 0.25-mm i.d., 0.25 μm
film thickness). A GC-MS system was employed using a
6890GC-5975N MS with an ECNI source. A 7000A triple
quadrupole was combined with a 7890A GC using an elec-
tron impact ion source. A sample was injected by a 7683B
Series Injector into a DB-5MS (30-m length, 0.25-mm i.d.,
0.25 μm film thickness) capillary column as well as a
GC-ECNI-LRMS system (all of the above instruments and
columns were from Agilent Technologies). An accelerated
solvent extractor (ASE) was a Dionex ASE 350 (Dionex
Canada Ltd., Oakville, ON, Canada), and a rotary evapora-
tor was a Heidolph 4000.
1.4 Sample pretreatment
Soil samples were freeze-dried and homogenized by sieving
through a stainless steel 75-mesh (0.5 mm) sieve. An ali-
quot of 5 g of sample was mixed with 15 g anhydrous
Na
2
SO
4
, spiked with 10 ng
13
C
10
-trans-chlordane and ex-
tracted by using a Dionex ASE 350 at 100°C and 1500 psi.
A mixture of dichloromethane and n-hexane (11) was used
as the extraction solvent. The thermal equilibration time
was 5 min, and the static extractions were performed within
three cycles (10 min/cycle). The cell was purged with
gaseous nitrogen for 100 s. After extraction, about 2 g of
activated copper powder was added to the extract to remove
elemental sulfur, and filtered through approximately 5 g of
anhydrous sodium sulfate. The extract was rotary-
evaporated to about 2 mL and cleaned by passing through a
multi-layered Florisil column containing, from bottom to
top, 3 g of activated Florisil, 2 g of activated silica gel, 5 g
of acid silica gel (30%, w/w) and 4 g anhydrous sodium
sulfate. The column was pre-cleaned with 50 mL hexane.
After loading the samples, CPs congeners were eluted with
40 mL hexane followed by 120 mL DCM and hexane (11).
The eluent was concentrated to 2 mL on the rotary evapo-
rator. The volume was further reduced with a gentle nitro-
gen flow and the solvent was changed to 100 μL cyclohex-
ane in a mini vial. 10 ng ε-HCH was added and the vial
mixed by vortexing prior to GC injection.
Question
1. What is chlorinated paraffin wax used for?
It is used in lubricants as an extreme pressure additive, where it forms a tenacious film on working parts. In cutting oils it is used as an additive to minimize ‘weld’ formation. In paints it is used as a plasticizer for binders and resins.
2. What is paraffin wax found in?
Paraffin wax is obtained from petroleum by dewaxing light lubricating oil stocks. It is used in candles, wax paper, polishes, cosmetics, and electrical insulators. It assists in extracting perfumes from flowers, forms a base for medical ointments, and supplies a waterproof coating for wood.
3. How to make chlorinated paraffin wax?
Paraffin Wax is melted in a vessel provided with steam jacket. The molten wax is charged to a glass lined chlorinator jacketed for steam heating. Dry chlorine gas is introduced to the mass of melted wax from bottom at regulated rate. The reaction temperature is maintained at 100oc for 18 to 20 hours.
4. Is paraffin wax safe?
Simply put, paraffin candles aren’t bad for our health or indoor air quality, but overwicked candles—made with any wax—can produce an excess of combustion compounds. The idea that paraffin candles burn less cleanly than others is a myth
5. Is paraffin safe for skin?
Experts generally consider paraffin wax to be safe and effective when used in a spa or at home in the form of moisturizers or heat therapy. However, a person should avoid using paraffin wax if they have: any open cuts, wounds, or burns. issues with sensation in their hands or feet.