Perfluorinated Compounds Pollution Research Articles

A Review of Recent Advances in Detection and Treatment Technology for Perfluorinated Compounds

Perfluorinated compounds (PFCs) are a novel type of environmental pollutant with a specific structure. PFCs have become a global concern due to their environmental persistence and biotoxicity properties. In this paper, we review the hazardous effects, detection technologies, and treatment methods of PFCs. We present the current status of PFCs pollution in water, the atmosphere, soil, and organisms. Moreover, we show that PFCs have toxic effects, such as hepatotoxicity, neurotoxicity, immunotoxicity, endocrine disruption, and reproductive and developmental toxicity. Six sample pretreatment techniques and four assays for PFCs are listed in this paper. This review focuses on the analysis of the treatment methods for PFCs, such as physical adsorption, microbial degradation, photochemical oxidation, electrochemical oxidation, acoustic oxidation, Fenton oxidation, and so on. We systematically analyze the treatment effects, removal mechanisms, and future directions of various technologies to provide support and suggestions for PFCs pollution control technologies.

Perfluorinated compounds (PFCs) in regional industrial rivers: Interactions between pollution flux and eukaryotic community phylosymbiosis

Perfluorinated compounds (PFCs) pose serious threats to aquatic ecosystems, especially their microbial communities. However, little is known about the phylosymbiosis of aquatic fungal and viridiplantae communities in response to PFC accumulation. We quantified the distribution of 14 PFCs in rivers and found that PFBA was dominant in the transition from water to sediment. High through-put sequencing revealed that phyla Ascomycota, Basidiomycota, Anthophyta, and Chlorophyta were the predominant in eukaryotic community. The effects of PFCs on spatial community coalescence at taxonomic and phylogenetic levels (p < 0.05) were revealed. Fungal community coalescence triggered the spatial assembly of fungal and viridiplantae communities in riverine environments (p < 0.05). Null modeling indicated that PFBA, PFTrDA and PFOS, etc, mediated phylogenetic assembly (p < 0.05) and stochastic processes (86.67–100%) maintain phylogenetic turnover in the fungal community. Meanwhile, variable selection (27.78–54.44%) explained the viridiplantae community assemblage. Finally, we identified fungal genera Hannaella, Naganishia, Purpureocillium and Stachybotrys as indicators for PFC pollution (p < 0.001). These results help explain the effects of PFCs on riverine ecological remediation.

Metagenomic analysis of soil microbial community under PFOA and PFOS stress

Perfluorinated compounds (PFCs) contamination of soil has attracted global attention in recent years but influences of PFCs on microorganisms in the soil environment have not been fully described. In this study, the effects of perfluorooctane sulphonate (PFOS) and perfluoroctanoic acid (PFOA) on bacterial communities were determined by Illumina Miseq sequencing and Illumina Hiseq Xten. The stimulation of PFCs pollutants on soil bacterial richness and community diversity were observed. Sequencing information indicated that Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, Firmicutes, and Gemmatimonadetes were the dominant bacterial phyla. Two genera, Bacillus and Sphingomonas, exhibited adverse responses toward PFCs pollution. Carbohydrate-active enzymes (CAZy), Kyoto Encyclopedia of Genes and Genomes (KEGG) and NCBI databases were used to elucidate the proteins and function action of soil microbial to PFCs pollution. Pathways such as Carbohydrate metabolism, Global and overview maps and Membrane transport in the soil microbes were affected by PFCs stress. CAZy analysis revealed that glycosyl transferases (GTs) in PFCs-polluted soils showed more active, while glycoside hydrolases (GHs) were inhibited severely.

Distribution of Perfluorinated Compounds in Surface Water and Soil in Partial Areas of Shandong Province, China

ABSTRACTThe work investigated the distribution of twelve perfluorinated compounds (PFCs) in surface water and soil in the partial areas of Shandong Province, China. The total concentration of PFCs was in the range of 36.1–1,236.21 ng/L in surface water and 4.23–48.72 ng/g dw (dry weight) in the soil. The concentration of PFOA is higher than that of PFOS in all the surface water and soil. There was a positive correlation between PFOS and PFOA. The ratio method and principal component analysis (PCA) were used to identify the potential source of PFCs in surface water. The results showed that atmospheric precipitation, industrial emissions and domestic sewage were the main reasons for PFCs pollution in the surface water of partial areas of Shandong Province, China.

Distribution of perfluorinated compounds (PFASs) in the aquatic environment of the industrially polluted Vaal River, South Africa

Perfluorinated alkyl substances (PFASs) are highly persistent chemicals, which have a bioaccumulative potential and can be found in wildlife around the world. Although multiple studies have been performed on PFASs pollution of the aquatic environment, little is known on PFASs pollution on the African continent and their possible risks for human health. In the present study, we examined the distribution of 15 PFASs in fish, invertebrates, sediment and water, collected at three sites, representing a gradient of industrial and mining pollution, along the Vaal River, South Africa. Furthermore, possible risks for human health through consumption of contaminated fish were examined.Perfluorooctane sulfonate (PFOS) was the most dominant PFAS measured in biota, whereas perfluoropentanoic acid (PFPeA) was measured in higher concentrations in water. Mean PFAS concentrations in water ranged from <LOQ to 38.5ng/L. PFAS concentrations in water decreased along the gradient and were similar or lower compared to other studies in Europe, Asia and America. PFAS measurements in sediment were <LOQ, with the exception of PFOS at Thabela Thabeng (2.36ng/g dry weight (dw)). Average ∑PFAS concentrations in biota increased along the gradient and ranged from <LOQ to 34.5ng/g wet weight (ww) in invertebrates, <LOQ to 289ng/g ww in liver and <LOQ to 34.0ng/g ww in muscle tissue. Although PFOS concentrations were relatively high compared to literature, concentrations of other PFASs were rather low.A potential risk for humans through consumption of PFAS-contaminated fish was assessed. Tolerable daily intake values (grams of fish that can be eaten daily without risking health effects) were much lower than the average South African fish consumption per day, implying a potential risk for human health through consumption of PFAS contaminated fish. CapsuleConcentrations of perfluorinated compounds in water, sediment, fish and invertebrates from the Vaal River were low or intermediate and posed a potential risk for human health through consumption of contaminated fish.

Effect of PFOA/PFOS pre-exposure on the toxicity of the herbicides 2,4-D, Atrazine, Diuron and Paraquat to a model aquatic photosynthetic microorganism

Pre-exposure to the perfluorinated compounds (PFCs) perfluorooctano sulphonate (PFOS) or perfluorooctanoic acid (PFOA) on the toxicity of four herbicides of different types and modes of action towards the self-luminescent recombinant cyanobacterium Anabaena CPB4337 was evaluated. The rationale of the approach is that both PFOS and PFOA as surfactants are known to modify cell membrane properties and pre-exposure to them might alter herbicide toxicity towards the cyanobacterium. Anabaena CPB4337 was pre-exposed during 72h to PFOS or PFOA at a concentration below their no observed effect concentration (NOEC). After pre-exposure, cells were exposed to increasing concentrations of 2,4-D Atrazine, Diuron and Paraquat and the toxicity was compared to that of non-pre-exposed ones. The data clearly showed that PFCs pre-treatment significantly altered the toxicity of the tested herbicides. However the effects resulting from PFOA and PFOS pre-exposure were not homogeneous for all the herbicides. In general PFOA pre-exposure resulted in increased herbicide toxicity except for atrazine, while PFOS pre-exposure resulted in increased toxicity for paraquat and diuron, and reduced toxicity for atrazine with no significant effect on 2,4-D toxicity. The strongest modifying effect was found for paraquat whose toxicity doubled with PFOA pre-exposure. Further analysis of membrane properties by flow cytometry revealed that both PFOA and PFOS were able to modify membrane integrity and membrane potential of Anabaena CPB4337 at the concentrations used in the pre-exposure experiments. These results reveal relevant indirect effects of PFCs pollution with eco-toxicological implications.

Perfluorinated compounds pollution fingerprints in typical industries of Shenzhen

Perfluorinated compounds pollution fingerprints in typical industries of Shenzhen

Occurrence of perfluorinated compounds in water and sediment of L’Albufera Natural Park (València, Spain)

Perfluorinated compounds (PFCs) are widely distributed from industrialized to remote locations throughout the world. This study demonstrates the spatial distributions of PFCs in water and sediments from the L'Albufera Natural Park (Valencia, Spain). Grab water and sediment samples were collected. PFCs were extracted from sediments with acidified acetonitrile by ultrasonication and cleaned up by solid-phase extraction (SPE) and from water by SPE. Determination was carried out by liquid chromatography-tandem mass spectrometry. In 100% of the samples (both water and sediments), perfluorooctane sulfonate (PFOS) and perfluoroctanoic acid (PFOA) were the predominant PFCs. Among the 12 sampling sites, PFOS concentrations in sediments ranged from 0.10 to 4.80 ng/g dry weight and in water from 0.94 to 58.1 ng/L. PFOA concentrations in sediment were from 0.004 to 1.24 ng/g and in water from 0.99 to 120 ng/L. Other perfluorocarboxylic acids (C5, C6, C7, C9, and C10) and perfluorosulfonates (C4 and C10) were also identified in several locations. The sum of all 10 compounds (ΣPFCs) concentration range from 0.99 to 120 ng/L in water and from 0.25 to 17.4 ng/g in sediments. Sediment-water distribution coefficients (log K (D)) were in the range 2.31-4.51 and positively correlated with perfluoroalkyl chain length. PFC concentrations in water and sediment were both less than those able to cause acute toxicity; low but detectable PFCs pollution in the L'Albufera Natural Park in Valencia was demonstrated. These compounds are bioaccumulative; thus, the risk associated with these exposures requires a deeper evaluation of long-term chronic toxicity.

Progress and perspective of perfluorinated compound risk assessment and management in various countries and institutes

Perfluorooctane sulfonate (PFOS) and related compounds have recently been designated as target chemicals for regulation by the Stockholm Convention on Persistent Organic Pollutants (POPs). Many countries have investigated and tried to implement various countermeasures in response to this decision. In this article, we collect reports concerning regulations and risk evaluations of perfluorinated compounds (PFCs) and review the current PFC management practiced in various countries. The first part of this review contains a comprehensive collection of proposed standard PFC values, including provisional tolerable daily intakes (pTDI), drinking water guidelines, and predicted non-effect concentrations (PNEC). The pTDI values ranged from 0.1 to 0.3 μg/kg/day for PFOS, and there are wide margins of safety for adults. Health risks for plant workers exposed to PFCs and for infants are of particular concern. The application of these proposed values in controlling PFC pollution is one approach that may effectively control human health risk without unduly sacrificing the benefits from PFC use. The second part of this review contains a collection and review of a number of regulations and countermeasures, such as an EU directive, regulation in Canada, and the Significant New Use Rule (SNUR), including voluntary control (i.e., production phase-out by 3M, stewardship programs, regulation in the semiconductor industry). Most of these regulations are based principally on the precautionary principle. However, they may not be as effective in pollution reduction as intended because the chemicals in question are already widely distributed in the environment owing to their use and mobility in the environment. In addition, these types of regulations would be non-operative in developing countries because rapidly growing economies place great demand on high performance materials, including PFCs. Further development of risk assessment methods that allow the evaluation of the counter risks of PFC alternatives and the loss of benefits from the PFC ban is necessary because of the possible continuous use of PFCs, especially in developing countries.

Spatially Detailed Survey on Pollution by Multiple Perfluorinated Compounds in the Tokyo Bay Basin of Japan

Pollution from 35 perfluorinated compounds (PFCs) in the water of the Tokyo Bay basin was examined. The water in the basin contained relatively high levels of perfluorononanoate (PFNA), perfluorooctanoate (PFOA), and perfluorooctane sulfonate (PFOS) compared to the other PFCs, which were present at concentrations of 20.1 ng/L, 6.7 ng/L, and 5.8 ng/L, respectively. In contrast, the concentrations of their precursors and degradation products were an order of magnitude lower. Sewage treatment plant (STP) effluent in the area also contained high levels of PFNA compared with the river water samples (Mann-Whitney U-test, p<0.0002). From a spatial aspect, increases in PFC pollution levels correlated with increased urbanization in the study area suggested that there are nonpoint source contributors to the PFC pollution in this area. Branched isomers of the PFCs were also quantified. Samples that contained high concentrations of perfluoroalkyl carboxylates (PFCA) showed lower proportions of its branched isomer. This indicates that the branched isomers are more prominent in the area with lower PFC pollution. This analysis was beneficial for estimating the individual contributions of different PFCA production processes. This survey provided new information on the sources, spatial distribution, and behavioral characteristics of PFC pollutants in this area.

Perfluorinated Compounds Distribution and Source Identification in Sediments of Lake Victoria Gulf Basin

Perfluorooctanoic acid and perfluorooctane sulfonate were determined in the sediments from Winam Gulf, which is in the Kenyan side of Lake Victoria and in its source rivers. The sources of perfluorinated compounds within the Gulf of Lake Victoria have been identified and their levels determined for the first time, in this study, using SPE and HPLC-MS-MS analytical methodology. Variability in the concentrations of perfluorooctanoic acid and perfluorooctane sulfonate ranged from 1.4–99.1 and <1–57.5 ng/g in river sediments, respectively, which was higher than concentrations obtained from lake sediments (range perfluorooctanoic acid <1–24.1 ng/g and perfluorooctane sulfonate <1–4.0 ng/g). The results obtained suggested generalized point sources such as domestic and industrial waste indicated by significant correlation and regression of r2 = 0.857. Sampling sites within and near sewage and water treatment facilities gave the highest concentrations of both analytes, and were observed to be the main source of perfluorinated compounds pollution. The lowest limit of quantification was 1 ng/g for both analytes and limits of detection were 0.1 and 0.2 ng/g for perfluorooctanoic acid and perfluorooctane sulfonate, respectively. Typical values for recovery obtained were higher than 78% from spiked amounts ranging from 1 to 150 ng. Quantifying perfluoro alkylated compounds in sediments have provided insights into their source, distribution, and mobility in the Lake Victoria Basin.

Evaluation of perfluorinated compounds in seven wastewater treatment plants in Beijing urban areas

The presence of perfluorinated compounds (PFCs) in seven major wastewater treatment plants (WWTPs) in Beijing was investigated in the current study. We detected nine PFCs in all the wastewater and sludge samples. Perfluorooctane acid (PFOA) is the dominant PFCs in influents and effluents, while perfluorooctane sulfonate (PFOS) is the major contaminant in sludge. The highest PFC concentration was found in plants at Qinghe and Jiuxianqiao WWTP, while the lowest was found at Fangzhuang WWTP. The total values of PFC range from 2.88 to 176 ng/L in influents, from 5.48 to 498 ng/L in effluents, and from 1.21 to 32.0 ng/g (dry wt) in sludge. The fact that effluents usually contain higher levels of PFCs than influents suggests that additional PFCs are produced during the wastewater treatment processes. However, PFOS decreases in effluents than in influents in 62% of the water samples. This may be due to the adsorption and removal of the sludge during the active process. Perfluoroalkyl carboxylates (PFCAs) were found significantly correlated with each other in the effluents, which may indicate their similar sources or the existence of their potential precursors in the wastewater or treatment processes. The mass flows of PFC discharges into WWTPs are 0.4–51.4 mg/day, and the mass flows of PFCs in effluents exceed those in influents by 127%. Domestic and commercial wastewaters are suggested to be the major sources of PFC pollution in WWTPs in Beijing.

Occurrence of perfluorinated compounds in fish from Qinghai-Tibetan Plateau

Perfluorinated compounds (PFCs) were found in fish muscle collected from high mountain lakes in the Qinghai-Tibetan Plateau, the highest and biggest plateau on Earth. In 96% of the total fifty-nine fish samples were found detectable perfluorooctane sulfonate (PFOS) as prominent PFCs, while only three for perfluorooctanoate (PFOA). The mean PFOS concentrations in fish muscle ranged 0.21ng/g–5.20ng/g based on dry weight, with the maximum in the Palgon Lake (1.30ng/g–7.54ng/g, dw) and the minimum in the Ni-yang River (<0.15ng/g–0.32ng/g, dw) among the seven sampling sites. Long-chain perfluorocarboxylic acids (C10, C11) were also identified in several locations. No significant correlations were observed between PFCs concentrations and sampling altitude or ages (fish). Results of the present work have demonstrated the existence of low level but detectable PFCs pollution in the Qinghai-Tibetan Plateau in China.

Existence of nonpoint source of perfluorinated compounds and their loads in the Tsurumi River basin, Japan

Products containing perfluorinated compounds (PFCs) have been widely used during the last 50 years. As a result, worldwide environmental pollution by PFCs has been reported. The sources of PFC pollution in the aquatic environment have been poorly understood. In this study, river water and sewage treatment plant (STP) effluent were sampled along the stretch of the Tsurumi River and also at a fixed station in the river. The concentrations of perfluorooctanesulfonate (PFOS), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were measured. With an increase in river flow rate, it was observed that the PFC concentrations in the river water at fixed station were remained the same or increased for PFOS (179.9 ± 34.4–179.6 ± 69.5 ng l −1), PFHxA (5.5 ± 0.8–9.0 ± 2.6 ng l −1), PFHpA (3.1 ± 0.3–4.4 ± 1.0 ng l −1), and PFOA (15.9 ± 0.3–13.4 ± 2.5 ng l −1) whereas the concentration of PFNA (38.0 ± 3.3–15.4 ± 3.0 ng l −1) and PFDA (3.9 ± 0.3–2.1 ± 0.3 ng l −1) were decreased. On the other hand, the loads of every PFC increased with an increase in river flow rate. The loads of PFCs in rain runoff were estimated to be 2–11 times greater than those in STP effluents that are discharged into the river. These results indicate the existence of a PFC nonpoint source (NPS) and its impact to the total PFC load of river is significant.