Research has been focused on the health hazards of ambient PM 2.5 related to humans. Many PM 2.5 toxicity assessments using in vitro studies have focused on PM 2.5 -bounded hazardous pollutants. However, PM 2.5 toxicity assessment by in vivo studies allow for better observation of the overall effects of PM 2.5 exposure on entire organisms, making in vivo PM 2.5 toxicity assessment relevant. The toxic effects of outdoor PM 2.5 , collected from
The goal of this report is to evaluate brominated persistent organic pollutants (POPs) in the indoor air and dust to further assess their health effects on thyroid hormones and neurodevelopment in infants, toddlers, and young children. This category of brominated POPs includes polybrmonated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), polybrominated biphenyls (PBBs), and polybrominated dibenzo-p-dioxins (PBDD/DFs). These organobromines are lipophilic compounds which resist physical and chemical degradation in the environment and biota, and so easily bioaccumulate in adipose tissue. Brominated POPs, particularly in brominated fire retardants (BFRs) such as PBDEs, HBCDs, and PBBs, are ubiquitous in indoor environments due to their inadvertent release from certain consumer products. Some of these organobromines have been recognized in some in-vitro and in-vivo studies to be neurotoxins and disrupt thyroid hormones, although the evidence from actual epidemiological studies is contradicted and inconsistent, especially for infants, toddlers, and young children, who are particularly vulnerable to these substances as they spend most of their time in the home. This report focuses on exposure to PBDEs, HBCDs, PBBs, and PBDD/DFs in the indoor dust and on the indoor aerosol, to explore their association with human health, particularly the disruption of thyroid hormones and neurodevelopment in early childhood.
In the present study, 168 pesticides in 1,017 samples of 10 Chinese herbal medicines (CHMs) were simultaneously determined by high-performance liquid (HPLC-MS/MS) and gas (GC-MS/MS) chromatography–tandem mass spectrometry. A total of 89.2% of the samples encompassed one or multiple pesticide residues, and the residue concentrations in 60.5% of samples were less than 0.02 mg kg−1, revealing the relatively low residue levels. The hazard quotient and hazard index methods were used to estimate the health risk for consumers. For a more accurate risk assessment, the exposure frequency and exposure duration of CHMs were involved into the exposure assessment, which was obtained from a questionnaire data of 20,917 volunteers. The results of chronic, acute, and cumulative risk assessment indicated that consumption of CHMs is unlikely to pose a health risk to consumers. Ranking the risk of detected pesticides revealed that phorate, BHC, triazophos, methidathion, terbufos, and omethoate posed the highest risk. Our results also showed that pollution of the aboveground medicinal part was more serious. Although exposure to pesticides in tested CHMs was below dangerous levels, more strict controlled management should be carried out for banned pesticides due to the high detection rate and illegal use in the actual planting practice.
BACKGROUND: Aqueous two-phase extraction has advantages of green extraction, high yield, good product purity and low cost. However, conventional aqueous two-phase systems (ATPSs) are limited in extraction/separation due to high polarity. Some researchers tuned the hydrophobicity of ATPSs by addition of hydrophobic ionic liquids or polymers. We aimed to tailor the hydrophobicity of a solvent-salt-water ATPS using cosolvent for extraction of paeonol from cortex moutan.
RESULTS: Tie-line length and compositions in the ATPSwere employed for qualitative evaluation of polarity and polarity difference between the two phases. Conditions such as pH, salt type and concentration, total solvent volume fraction and cosolvent fraction were optimized. Ethyl acetate (EA) as cosolvent in ethanol-NaH 2 PO 4 -H 2 O (EtPO) system did not alter the first-order kinetic extraction model, but it improved the kinetic constant and boosted the partition coefficient from 36.7 to 58.8. For both EtPO and EtPO-EA systems, both the extraction yields and partition coefficients increased when temperature increased from 11 to 37 ∘ C. The optimized EtPO-EA system demonstrated higher extraction yield than EtPO and 70% (v/v) ethanol systems by 25.4 and 19.5%, respectively. CONCLUSIONS: The hydrophobicity of an ATPS was successfully tuned with cosolvent for paeonol extraction. The cosolvent-salt-water two-phase systems are promising in extraction of weakly polar components from herbs.
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