Air–soil exchange of and risks posed by short- and medium-chain chlorinated paraffins: Case study in a contaminated area in China

Self Cite

Chlorinated paraffins (CPs) are used in many products, including soft poly(vinyl chloride) curtains, which are used in many indoor environments. Health hazards posed by CPs in curtains are poorly understood. Here, chamber tests and an indoor fugacity model were used to predict CP emissions from soft poly(vinyl chloride) curtains, and dermal uptake through direct contact was assessed using surface wipes. Short-chain and medium-chain CPs accounted for 30% by weight of the curtains. Evaporation drives CP migration, like for other semivolatile organic plasticizers, at room temperature. The CP emission rate to air was 7.09 ng/(cm2 h), and the estimated short-chain and medium-chain CP concentrations were 583 and 95.3 ng/m3 in indoor air 21.2 and 172 μg/g in dust, respectively. Curtains could be important indoor sources of CPs to dust and air. The calculated total daily CP intakes from air and dust were 165 ng/(kg day) for an adult and 514 ng/(kg day) for a toddler, and an assessment of dermal intake through direct contact indicated that touching just once could increase intake by 274 μg. The results indicated that curtains, which are common in houses, could pose considerable health risks through inhalation of and dermal contact with CPs.

Section: Resultssupporting

confidence: 70%

Health Risks Posed by Dermal and Inhalation Exposure to High Concentrations of Chlorinated Paraffins Found in Soft Poly(vinyl chloride) Curtains

Weng

Zhang

et al. 2023

Self Cite

“…This finding is consistent with the continuous increase in the global production of MCCPs in recent years, highlighting MCCP pollution as a growing environmental concern. Previous research has also shown higher levels of MCCPs compared to SCCPs in various environmental sources such as soil, Tibetan butter, clothing, and honey . In contrast to our current study, our previous work found that the dominant congeners in honey, bees, bee pollen, and beeswax were C 10–11 Cl 6–7 for SCCPs and C 14 Cl 6–7 for MCCPs, in honey, bees, bee pollen, and beeswax .…”

Section: Resultscontrasting

confidence: 99%

Tissue-Specific Accumulation of Orally Administered Short- and Medium-Chain Chlorinated Paraffins in Honeybees (Apis mellifera L.)

Dong,

Qi,

Zhang

et al. 2024

The prevalence and distribution of chlorinated paraffins (CPs) have been extensively studied in various matrices and organisms; however, there is a lack of information about insects, particularly in honeybees. To address this gap, we studied young honeybee workers exposed to short-and medium-chain CPs (SCCPs and MCCPs) at an environmentally relevant concentration of 10 mg/L for 7 days, followed by a 7-day elimination period. Results indicated that CPs could transfer into the head after oral consumption and SCCPs and MCCPs exhibited clear bioaccumulation trends: midgut > hindgut > head. An evaluation of congener group distribution patterns demonstrated that the dominant congener groups in all target tissues were C 11−13 Cl 7−8 and C 14 Cl 7−8 for SCCPs and MCCPs, respectively, consistent with the treated CP standards. In honeybees, a significant negative relationship was observed for the log concentration of MCCP congener groups and their log K OW , but not with their log K OA . Conversely, no such correlation was found for SCCPs. These findings suggest that honeybees have a high potential to bioaccumulate MCCPs, particularly those with a low log K OW , and exhibit weak selectivity for SCCPs.

“…GC × GC has distinct advantages for SCCP group analysis and can effectively reduce qualitative interference among congeners. The measurement of SCCP congener patterns was carried out using a GC × GC system (7890, Agilent Technologies), a thermal modulator (zx2004, Zoex Corporation, USA), and a TOF mass spectrometer (Tofwerk, Switzerland) operated in ECNI (electron-capture negative ionization) mode with a splitless injection. − A DB-5MS column (30 × 0.25 mm, 0.25 μm; Agilent Technologies) was used as a first-dimension column, and a moderate polarity BPX-50 column (1 × 0.10 mm, 0.10 μm) (SGE, USA) was used as a second-dimension column. Each diluted CP sample was spiked with 2.5 ng of ε-hexachlorocyclohexane in 50 μL of cyclohexane.…”

Section: Methodsmentioning

confidence: 99%

Occurrence and Formation Mechanism of PCDD/Fs and SCCPs in Chlorinated Paraffin Products

He,

Liu,

Gao

et al. 2023

Self Cite

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and short-chain chlorinated paraffins (SCCPs) can be formed during the production of chlorinated paraffins (CPs). Detection and accurate quantification of PCDD/Fs in CPs are challenging because of their matrix complexity. Therefore, the occurrence and formation mechanisms of PCDD/Fs from CPs have not been studied extensively in the past. In this study, 15 commercial samples including solid and liquid CPs were collected in 2022 from China. The average ΣSCCP concentrations detected in the solid and liquid CPs were 158 and 137 mg/g, respectively. The average International Toxic Equivalent (I-TEQ) values of 2,3,7,8-PCDD/F in solid and liquid CPs were 15.8 pg I-TEQ/g and 15.0 pg I-TEQ/g, respectively. The solid and liquid CPs had different predominant congener groups for SCCPs and PCDD/Fs. Possible formation routes for the generation of PCDD/Fs were analyzed by screening precursors in paraffin and laboratory-scale thermochemical experiments of CPs. The transformation between 2,3,7,8-PCDD/Fs and non-2,3,7,8-PCDD/Fs was recognized by calculating the successive chlorination preference. The first reported occurrence of PCDD/Fs in CP commercial products indicated that exposure to CPs and downstream products might be an assignable source of PCDD/F emission, which is of great significance to further explore the control factors of PCDD/Fs in the whole life cycle of CPs.