A gas chromatography/mass spectrometry method for the simultaneous analysis of 50 phenols in wastewater using deconvolution technology

S B, Nerella SG, R J, G. G K, V SS. Evaluation of phytoconstituents in marigold effluent for their antifungal activity against plant pathogens

The current study placed an intense emphasis on the excess discharge of agro-based industrial effluent and the use of plant extract antimicrobials to inhibit the growth of pathogens in crop plants. An effluent (treated and untreated) from the marigold flower processing industry has been identified for the presence of volatile and semi-volatile organic compounds, and a total of 18 in treated effluent and 23 in untreated effluent were found using gas chromatography-mass spectrometry. A total of 13 classes were identified, which include carboxylic acid, phenols, esters, alkanes, alkenes, alcohols, cyanide, heterocyclic, flavonoids, aldehydes, polycyclic aromatic, cycloalkanes, and cycloalkenes. A principal component analysis with varimax rotation was applied to discern the abundance of identified compounds under each class. An in vitro antifungal bioassay was conducted using effluents at three different concentrations against plant pathogens (Alternaria alter nata, Sclerotium rolfsii, Rhizoctonia solani, Pythium aphanidermata, Fusarium oxysporum, and Colletotrichum gloeosporioides). The study proved that treated and untreated effluents clearly inhibited the growth of fungal pathogens by 10 to 32% and 37 to 92%, respectively. The findings suggest that marigold flower effluent can be a promising resource for developing new plant protection methods that are effective against pathogenic fungi.

Simultaneous determination of forty-two parent and halogenated polycyclic aromatic hydrocarbons using solid-phase extraction combined with gas chromatography-mass spectrometry in drinking water

The coexistence of parent polycyclic aromatic hydrocarbons (PPAHs) and halogenated PAHs (HPAHs) in drinking water has generated much concern recently. However, a method to simultaneously determine these compounds has not been developed. In this study, a method using solid-phase extraction combined with gas chromatography-mass spectrometry for determination of PPAHs and HPAHs in drinking water was established. Forty-two target compounds including 16 PPAHs and 26 HPAHs (16 chlorinated PAHs (Cl-HPAHs) and 10 brominated PAHs (Br-PAHs)) were selected to evaluate the performance. Our results indicate enriching compounds with a LC18 cartridge and eluting with dichloromethane is optimal with recovery of 74.88-119.4%. Method detection limits ranged from 0.34 to 3.37 ng L^-1 when only using 1 L samples. The method accomplished the analysis of trace PPAHs and HPAHs. We found the coexistence of PPAHs and HPAHs including 12 PPAHs, 2 Cl-PAHs and 3 Br-PAHs in tap water samples. Maximum total concentration of PPAHs and HPAHs reached 33.69 ng L^-1 and 3.04 ng L^-1, respectively. Trace Br-PAHs were first detected in drinking water. 6-bromobenzene[a]pyrene was dominated among the HPAHs with a concentration from 2.30 to 2.69 ng L^-1. The simultaneous occurrence of PPAHs and HPAHs in drinking water should receive more attention, and their formation mechanism should be further explored.

Simultaneous passive sampling of hydrophilic and hydrophobic emerging organic contaminants in water

Passive sampling techniques have been considered robust tools for monitoring freely dissolved concentrations of contaminants in aquatic systems. However, few passive samplers are currently available for the simultaneous sampling of both hydrophilic and hydrophobic chemicals. In this study, we developed a novel passive sampler (a hydrophilic-lipophilic balance sorbent-embedded cellulose acetate membrane (HECAM)) for estimating the time-weighted average (TWA) concentrations of both hydrophilic and hydrophobic organic contaminants in water. In our laboratorial controlled dynamic experiments, the accumulation results of thirty-seven target chemicals (including organophosphorus flame retardants, phenols, estrogens, organophosphorus pesticides, and triazine herbicides) with a wide polarity range (1.44 < log K_ow < 9.49) in the HECAM followed first-order kinetics well, and the passive sampling parameters were estimated successfully. The estimated sampling rates for the target chemicals in the HECAM ranged from 0.14 to 6.90 L d^-1 in the laboratory experiment, and the log K_sw (equilibrium partition coefficient between the sampler and water) values ranged from 2.75 to 6.00. The HECAM exhibited high sampling rate for moderately hydrophilic and moderately hydrophobic chemicals. The field validation study in an urban river resulted in the detection of four target chemicals (tris(chloroisopropyl)phosphate, tris(1,3-dichloroisopropyl)phosphate, prometryn, and 4-tert-octylphenol) by the HECAM at estimated TWA concentrations of 10.9-179.5 ng L^-1, which were in agreement with the measured levels found in traditional grab samples by solid-phase extraction. In summary, both the laboratory tests and field deployment showed practicable results for the HECAM passive sampling, which suggests that it is an efficient approach for simultaneous monitoring of hydrophilic and hydrophobic organic contaminants in water.

Distribution and potential ecological risk of 50 phenolic compounds in three rivers in Tianjin, China

Phenolic compounds widely exist in the surface water of many countries; however, few studies have simultaneously analyzed and evaluated broad-spectrum phenolic compounds in various components of the water environment. Therefore this study analyzed the distribution and potential ecological risk of 50 phenolic compounds in the surface water, sediment and suspended particulate matter of three important rivers in Tianjin, the main heavy industry city with high pollution in China. The qualitative results show that phenolic pollution existed extensively in the three rivers and the kinds of phenolic compounds in the water were relatively higher than in both sediment and suspended particulate matter. The quantitative results show that the phenolic pollution in the wet-season samples was serious than dry-season samples. Meanwhile, total concentrations of phenolic compounds in three components from the Dagu Drainage River (DDR) were all much higher than those in the Beitang Drainage River (BDR) and Yongdingxin River (YDXR). The highest total concentrations of phenolic compounds in three components all appeared in wet-season samples in DDR, and the highest total concentration was 1354 μg/L in surface water, 719 μg/kg dw in suspended particulate matter and 2937 μg/kg dw in sediment, respectively. The ecological risk of phenolic compounds in surface water was evaluated using the quotient method, and phenolic compounds with risk quotient (RQ) > 1 (RQ > 0.3 for YDXR) were identified as priority pollutants. Five kinds of phenolic compounds were identified as priority phenolic compounds in BDR, and the order of risk was 2-cresol > 2,4-xylenol > 2-sec-butylphenol > 2-naphthol > 3-cresol. Six kinds of phenolic compounds were identified as priority phenolic compounds in DDR, and the order of risk was 2-naphthol > p-chloro-m-xylenol > 4-cresol > 3-cresol > 2,4-xylenol > 2,3,6-Trimethylphenol. In YDXR, only phenol, 2-naphthol and 2,4-xylenol were identified as priority phenolic compounds.

Data on contents of fifty phenolic compounds in three rivers in Tianjin, China

This article contains data related to the research article entitled “Distribution and potential ecological risk of 50 phenolic compounds in three rivers in Tianjin, China” [1]. This data article reports the detailed information for the contaminant level of phenolic compounds in three rivers in Tianjin, China. The data collects from seven sample sites in Beitang drainage river, sixteen sample sites in Dagu drainage river, and fourteen sample sites in Yongdingxin river. The ranges, standard deviations, average values, median values of the concentrations of identified phenolic compounds in three rivers and the standard deviations, average values, the maximum values of risk quotients of identified phenolic compounds in three rivers are listed in this paper.

Pentachlorophenol affected both reproductive and interrenal systems: In silico and in vivo evidence

The present study investigated the effects on reproductive and interrenal system by pentachlorophenol (PCP) using in silico and in vivo assays. Molecular docking results indicated interacting potency of PCP with steroid receptors (ERα, ERβ, AR, GR) but not Cytochrome P450 enzymes (CYPs). In the in vivo assay, sexually matured rare minnow (Gobiocypris rarus) was exposed to environmental relevant concentrations of PCP (0, 0.5, 5, 50 μg L^-1). In male fish, 14-d exposure caused up-regulation of mRNA levels of hepatic erα, erβ, ar, gr, vtg and gonadal erα, vtg, ar, dmrt1, providing evidence for agonistic activities for steroid receptors by PCP. The up-regulated mRNA of gnrh, crf, pomc in the brain also indicated feed-forward responses of the hypothalamic-pituitary-gonadal/interrenal (HPG/I) axis. However, at 28th d the feed-forward response of the HPG axis seemed eased back and the HPI axis showed negative feedback responses. Corresponding changes including increases of plasma steroid hormones, inhibition of spermatogenesis, and decreased RSI were observed in male fish upon 28-d exposure to PCP. In the females, a transition from feed-forward responses to negative feedbacks of the HPG/I axis was also indicated by the transcriptional profiles at 14th and 28th day. Corresponding changes including increased E2, T and decreased C levels, degenerated ovaries, and decreased GSI and RSI were also observed. Overall, we concluded that PCP could interfere with steroid receptors, evoke responses of HPG/I axis, and finally result in adverse effects on reproductive and interrenal system in rare minnow at environmental relevant concentrations.