Antibiotics are widely used in humans and animals, but there is a big concern about their negative impacts on ecosystem and human health after use. So far there is a lack of information on emission ...inventory and environmental fate of antibiotics in China. We studied national consumption, emissions, and multimedia fate of 36 frequently detected antibiotics in China by market survey, data analysis, and level III fugacity modeling tools. Based on our survey, the total usage for the 36 chemicals was 92700 tons in 2013, an estimated 54000 tons of the antibiotics was excreted by human and animals, and eventually 53800 tons of them entered into the receiving environment following various wastewater treatments. The fugacity model successfully predicted environmental concentrations (PECs) in all 58 river basins of China, which are comparable to the reported measured environmental concentrations (MECs) available in some basins. The bacterial resistance rates in the hospitals and aquatic environments were found to be related to the PECs and antibiotic usages, especially for those antibiotics used in the most recent period. This is the first comprehensive study which demonstrates an alarming usage and emission of various antibiotics in China.
Perfluoroalkyl substances (PFASs) are a group of chemicals with wide industrial and commercial applications, and have been received great attentions due to their persistence in the environment. The ...information about their presence in urban water cycle is still limited. This study aimed to investigate the occurrence and removal efficiency of eighteen PFASs in wastewater treatment plants (WWTPs) and drinking water plants (DWTPs) with different treatment processes. The results showed that both perfluorobutane sulfonic acid (PFBS) and perfluorooctane sulfonic acid (PFOS) were the predominant compounds in the water phase of WWTPs and DWTPs, while PFOS was dominant in dewatered sludge of WWTPs. The average total PFASs concentrations in the three selected WWTPs were 19.6–232 ng/L in influents, 15.5–234 ng/L in effluents, and 31.5–49.1 ng/g dry weight in sludge. The distribution pattern of PFASs differed between the wastewater and sludge samples, indicating strong partition of PFASs with long carbon chains to sludge. In the WWTPs, most PFASs were not eliminated efficiently in conventional activated sludge treatment, while the membrane bio-reactor (MBR) and Unitank removed approximately 50% of long chain (C ≥ 8) perfluorocarboxylic acids (PFCAs). The daily mass loads of total PFASs in WWTPs were in the range of 1956–24773 mg in influent and 1548–25085 mg in effluent. PFASs were found at higher concentrations in the wastewater from plant A with some industrial wastewater input than from the other two plants (plant B and plant C) with mainly domestic wastewater sources. Meanwhile, the average total PFASs concentrations in the two selected DWTPs were detected at 4.74–14.3 ng/L in the influent and 3.34–13.9 ng/L in the effluent. In DWTPs, only granular activated carbon (GAC) and powder activated carbon (PAC) showed significant removal of PFASs. The PFASs detected in the tap water would not pose immediate health risks in the short term exposure. The findings from this study showed that effective treatment technology should be applied to eliminate this group of chemicals in the urban water cycle based on the precautionary principle.
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•PFASs were detected in WWTPs and DWTPs.•PFBS, PFOS and PFOA were predominant compounds in WWTPs and DWTPs.•MBR and Unitank can effectively remove the long chain PFCAs.•Powder activated carbon is the best in the removal of PFASs.•PFASs in tap water of Guangzhou would not pose health risks in the short-term.
As emerging contaminants, antibiotic resistance genes (ARGs) have become a public concern. This study aimed to investigate the occurrence and diversity of ARGs, and variation in the composition of ...bacterial communities in source water, drinking water treatment plants, and tap water in the Pearl River Delta region, South China. Various ARGs were present in the different types of water. Among the 27 target ARGs, floR and sul1 dominated in source water from three large rivers in the region. Pearson correlation analysis suggested that sul1, sul2, floR, and cmlA could be potential indicators for ARGs in water samples. The total abundance of the detected ARGs in tap water was much lower than that in source water. Sand filtration and sedimentation in drinking water treatment plants could effectively remove ARGs; in contrast, granular activated carbon filtration increased the abundance of ARGs. It was found that Pseudomonas may be involved in the proliferation and dissemination of ARGs in the studied drinking water treatment system. Bacteria and ARGs were still present in tap water after treatment, though they were significantly reduced. More research is needed to optimize the water treatment process for ARG removal.
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•Diverse ARGs present in different types of waters.•Sul1, sul2, floR, cmlA could be potential indicators for ARGs in the water samples.•Sand filter and sedimentation were effective in removing ARGs.•Granular activated carbon filtration increased the ARGs abundance.•ARGs still existed in tap water after treatment despite significantly reduced.
This paper evaluated the excretion masses and environmental occurrence of 11 classes of 50 antibiotics in six typical swine and dairy cattle farms in southern China. Animal feeds, wastewater and ...solid manure samples as well as environmental samples (soil, stream and well water) were collected in December 2010 from these farms. Twenty eight antibiotics, including tetracyclines, bacitracin, lincomycin, sulfonamides, fluoroquinolones, ceftiofur, trimethoprim, macrolides, and florfenicol, were detected in the feeds, animal wastes and receiving environments. The normalized daily excretion masses per swine and cattle were estimated to be 18.2mg/day/swine and 4.24mg/day/cattle. Chlortetracycline (11.6mg/day/swine), bacitracin (3.81mg/day/swine), lincomycin (1.19mg/day/swine) and tetracycline (1.04mg/day/swine) were the main contributors to the normalized daily excretion masses of antibiotics per swine, while chlortetracycline (3.66mg/day/cattle) contributed 86% of the normalized daily excretion masses of antibiotics per cattle. Based on the survey of feeds and animal wastes from the swine farms and interview with the farmers, antibiotics excreted by swine were mainly originated from the feeds, while antibiotics excreted by dairy cattle were mainly from the injection route. If we assume that the swine and cattle in China excrete the same masses of antibiotics as the selected livestock farms, the total excretion mass by swine and cattle per annum in China could reach 3,080,000kg/year and 164,000kg/year. Various antibiotics such as sulfonamides, tetracyclines, fluroquinolones, macrolides, trimethoprim, lincomycin and florfenicol were detected in well water, stream and field soil, suggesting that livestock farms could be an important pollution source of various antibiotics to the receiving environments.
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► Twenty six antibiotics were quantified in six swine and dairy farms. ► The normalized excretion mass of antibiotics per swine was more than per cattle. ► Growth promoters contributed above 80% of the excretion mass in swine farms. ► Total excretion mass by swine and cattle in China could reach 3080 and 164t/a. ► Significant concentrations of antibiotics were found in the receiving environment.
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•First biomagnification report of alternative PFASs in subtropical marine food webs.•F-53B was detected in 44% of marine organisms (34 species) from the Beibu Gulf.•PFOS and F-53B ...were biomagnified (TMF of 1.75 and 1.69), other PFAS were biodiluted.•TMFs were lower in this subtropical food web than Arctic and temperate food webs.•HRs suggested low PFAS human health risks via seafood consumption in this area.
The usage of alternative per- and polyfluoroalkyl substances (PFASs) has been increasing due to the restriction and elimination of legacy PFASs. However, there is limited knowledge on bioaccumulation and trophic magnification of alternative PFASs, especially in subtropical ecosystems. In the present study, we performed a comprehensive survey to investigate the occurrence, bioaccumulation and trophic magnification of legacy and alternative PFASs in subtropical marine food webs in the Beibu Gulf, South China. Results showed that perfluorobutanoic acid (PFBA) and perfluorooctanoic acid (PFOA) were the predominant PFASs in water phase, while perfluorooctane sufonate (PFOS) contributed most to the sum of target PFASs in sediments and marine organisms. Of the investigated PFASs, PFOS and 6:2 chlorinated polyfluoroalkyl ether sulfonic acids (F-53B) exhibited the highest bioaccumulation factor with values > 5000, qualifying as very bioaccumulative chemicals. There was a significant positive correlation between log BSAF and the carbon chain length of perfluoroalkyl carboxylic acids (PFCAs). Trophic magnification (TMF) was observed for PFOS and F-53B, while the remaining PFASs were biodiluted through the present food web. The hazard ratios for PFOS and PFOA in all organisms were far less than unity, suggesting overall low PFAS risks for humans through consumption of marine organisms.
Abstract
Background
The high cost and insufficient supply of human papillomavirus (HPV) vaccines have slowed the pace of controlling cervical cancer. A phase III clinical trial was conducted to ...evaluate the efficacy, safety, and immunogenicity of a novel Escherichia coli-produced bivalent HPV-16/18 vaccine.
Methods
A multicenter, randomized, double-blind trial started on November 22, 2012 in China. In total, 7372 eligible women aged 18–45 years were age-stratified and randomly assigned to receive three doses of the test or control (hepatitis E) vaccine at months 0, 1, and 6. Co-primary endpoints included high-grade genital lesions and persistent infection (over 6 months) associated with HPV-16/18. The primary analysis was performed on a per-protocol susceptible population of individuals who were negative for relevant HPV type-specific neutralizing antibodies (at day 0) and DNA (at day 0 through month 7) and who received three doses of the vaccine. This report presents data from a prespecified interim analysis used for regulatory submission.
Results
In the per-protocol cohort, the efficacies against high-grade genital lesions and persistent infection were 100.0% (95% confidence interval = 55.6% to 100.0%, 0 of 3306 in the vaccine group vs 10 of 3296 in the control group) and 97.8% (95% confidence interval = 87.1% to 99.9%, 1 of 3240 vs 45 of 3246), respectively. The side effects were mild. No vaccine-related serious adverse events were noted. Robust antibody responses for both types were induced and persisted for at least 42 months.
Conclusions
The E coli-produced HPV-16/18 vaccine is well tolerated and highly efficacious against HPV-16/18–associated high-grade genital lesions and persistent infection in women.
We investigated the bioaccumulation of antibiotics in bile, plasma, liver and muscle tissues of wild fish from four rivers in the Pearl River Delta region. In total, 12 antibiotics were present in at ...least one type of fish tissues from nine wild fish species in the four rivers. The mean values of log bioaccumulation factors (log BAFs) for the detected antibiotics in fish bile, plasma, liver, and muscle tissues were at the range of 2.06–4.08, 1.85–3.47, 1.41–3.51, and 0.48–2.70, respectively. As the digestion tissues, fish bile, plasma, and liver showed strong bioaccumulation ability for some antibiotics, indicating a different bioaccumulation pattern from hydrophobic organic contaminants. Human health risk assessment based on potential fish consumption indicates that these antibiotics do not appear to pose an appreciable risk to human health. To the best of our knowledge, this is first report of bioaccumulation patterns of antibiotics in wild fish bile and plasma.
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•We investigated the bioaccumulation of antibiotics in wild fish from the Pearl River Delta region.•Twelve antibiotics were found in fish bile, plasma, liver and muscle tissues.•High log bioaccumulation factors suggested strong bioaccumulation ability for some antibiotics in wild fish tissues.•The presence of antibiotics in fish bile and plasma tissues indicates a novel bioaccumulation pattern.•Potential adverse effects are possibly caused by the high internal antibiotic concentrations in tissues.
Fish bile and plasma displayed strong bioaccumulation ability for some antibiotics, indicating a novel bioaccumulation pattern for antibiotics in the contaminated environment.
Per-and polyfluoroalkyl substances (PFASs) have received great attention due to their persistence, bioaccumulation and toxicity. Various activated carbons (ACs) exhibit wide variability in adsorptive ...performance towards PFASs. In order to gain a systematic understanding of adsorptive removal of legacy and emerging PFASs by ACs, the adsorption of ten PFASs on various ACs was comprehensively investigated. Results showed that granular activated carbon-1 (GAC-1) and powdered activated carbon-1 (PAC-1) removed more than 90% of all target PFASs. Particle size, surface charge, and micropores quantity of ACs were closely related to their performance for PFASs removal. Electrostatic interaction, hydrophobic interaction, surface complexation and hydrogen bonding were the adsorption mechanisms, with hydrophobic interaction being the predominant adsorptive force. Physical and chemical adsorption were both involved in PFAS adsorption. The removal rates of PFASs by GAC-1 decreased from 93%–100% to 15%–66% in the presence of 5 mg/L fulvic acid (FA). GAC was able to remove more PFASs under acidic medium, whereas PAC removed hydrophobic PFASs better under the neutral medium. The removal rates of PFASs by GAC-3 increased significantly from 0%–21% to 52%–97% after being impregnated with benzalkonium chlorides (BACs), demonstrating the superiority of this modification method. Overall, this study provided theoretical support for removing PFASs from water phase with ACs.
•Particle size and surface properties of ACs affect their efficiency for PFAS removal.•Removal of PFASs by GAC was probably homogenous physical adsorption.•Neutral medium was favorable for the removal of long-chain PFASs by PAC.•Adsorption of PFASs by GAC was enhanced significantly by BACs impregnation.
The widespread use of antibiotics has raised global concerns, but scarce information on antibiotics in the subtropical marine environment is available. In the present study, seawater and sediment ...samples were collected to investigate the occurrence, spatial distribution, source, and ecological risks of 22 antibiotics in the Beibu Gulf. The total concentrations of target antibiotics (∑antibiotics) were in the range of 1.74 ng/L to 23.83 ng/L for seawater and 1.33 ng/g to 8.55 ng/g dry weight (dw) for sediment. Spatially, a decreasing trend of antibiotic levels from coast to offshore area was observed, with relatively high levels at the sites close to the Qinzhou Bay and Qiongzhou Strait. Sulfamethoxazole (SMX), trimethoprim (TMP), and norfloxacin (NOX) were predominant in seawater, while NOX, enoxacin (ENX), and enrofloxacin (ENR) were the most abundant antibiotics in sediment. In general, the sediment-water partitioning coefficients (Kd) were positively correlated with log molecular weight (MW). Salinity, particle size, and pH of water were predicted to be vital factors influencing the partition of sulfadiazine (SDZ), CIX, and ENR (p < 0.05). Livestock and aquaculture were identified as dominant sources of antibiotics in the Beibu Gulf based on PCA-MLR and Unmix model. Risk assessment revealed that SMX, CIX could pose medium risks to algae in the Beibu Gulf. Overall, our results provided paramount insights into understanding the fate and transport behaviors of antibiotics in the subtropical marine environment.
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•19 and 17 antibiotics were detected in the seawater, sediment of the Beibu Gulf.•Σantibiotic levels were 1.74–23.83 ng/L for seawater and 1.33–8.55 ng/g for sediment.•Livestock activities and aquaculture were major antibiotics sources in the Beibu Gulf.•SMX, CIX may pose adverse ecotoxicological risks to algae.
Antibiotics are of particular concern because of their ubiquity in aquatic environment and long-term adverse effects on aquatic organisms and humans. However, there is no information about the ...bioaccumulation and trophic magnification of antibiotics in subtropical environments. In this study, we determined the concentrations of 22 antibiotics to investigate their occurrence, bioaccumulation and trophic magnification in a subtropical food web from the Beibu Gulf. The total concentrations of target antibiotics ranged from 52.94–77.76 ng/L in seawater, 9.69–15.43 ng/g dry weight (dw) in sediment, and 0.68–4.75 ng/g wet weight (ww) in marine organisms, respectively. Macrolides were the predominant antibiotics in water, while fluoroquinolones were more abundant in sediment and biota samples. The total concentrations of target antibiotics in examined marine taxa descended in the order: crustacean > cephalopod > fish, with antibiotic profiles displaying distinct difference among taxa. Log BAFs (bioaccumulation factor) for antibiotics in all organisms ranged from −0.50 for erythromycin-H2O (ETM-H2O) to 2.82 for sulfamonomethoxine (SMM). Significantly negative correlation was observed between the log Dow and log BAF values (p < .05), indicating that log Dow is a good predictor of antibiotics bioaccumulation potential in marine organisms. The trophic magnification factors (TMFs) for sulfadiazine (SDZ) and enoxacin (ENX) were greater than unity, suggesting the trophic magnification of these chemicals through the food web. In contrast, enrofloxacin (ENR), ciprofloxacin (CIX), ofloxacin (OFX), norfloxacin (NOX), ETM-H2O and trimethoprim (TMP) were biodiluted in the food web from the Beibu Gulf. This study provides substantial information on the fate and trophic transfer of antibiotics in a subtropical marine ecosystem.
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•First trophic transfer report of antibiotics in subtropical marine food webs.•The antibiotics residues were in the order of crustacean > cephalopod > fish.•Linear relationship was observed between log BAF and log Dow for antibiotics.•Carbon sources of organisms play a vital role in bioaccumulation of antibiotics.•Sulfadiazine and enoxacin were biomagnified along the food web in the Beibu Gulf.
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