Compound Triclosan Research Articles

Exploring Novel Antimalarial Compounds Targeting Plasmodium falciparum Enoyl-ACP Reductase: Computational and Experimental Insights.

Malaria, caused by Plasmodium protozoa with Plasmodium falciparum as the most virulent species, continues to pose significant health challenges. Despite the availability of effective antimalarial drugs, the emergence of resistance has heightened the urgency for developing novel therapeutic compounds. In this study, we investigated the enoyl-ACP reductase enzyme of P. falciparum (PfENR) as a promising target for antimalarial drug discovery. Through a comprehensive analysis, we conducted a comparative evaluation of two lead compounds, LD1 (CID: 44405336, lead compounds 1) and LD2 (CID: 72703246, lead compounds 2), obtained from the PubChem/NCBI ligand database, to serve as reference molecules in the identification of potential derivatives using virtual screening assays. Among the newly identified candidates, Ligand 1 (LG1) and Ligand 2 (LG2) exhibited intriguing characteristics and underwent further investigation through docking and molecular dynamics simulations. Ligand 1 (LG1) demonstrated interactions similar to LD1, including hydrogen bonding with Asp218, while Ligand 2 (LG2) displayed superior binding energy comparable to LD1 and LD2, despite lacking hydrogen bonding interactions observed in the control compounds triclosan and its derivative 7-(4-chloro-2-hydroxyphenoxy)-4-methyl-2H-chromen-2-one (CHJ). Following computational validation using the MM/GBSA method to estimate binding free energy, commercially acquired LG1 and LG2 ligands were subjected to in vitro testing. Inhibition assays were performed to evaluate their potential as PfENR inhibitors alongside triclosan as a control compound. LG1 exhibited no inhibitory effects, while LG2 demonstrated inhibitory effects like triclosan. In conclusion, this study contributes valuable insights into developing novel antimalarial drugs by identifying LG2 as a potential ligand and employing a comprehensive approach integrating computational and experimental methodologies.

Interleukin 1β and interleukin 6 production in human immune cells is stimulated by the antibacterial compound Triclosan.

Triclosan (TCS) is an antimicrobial compound widely used in personal hygiene products such as mouthwash and toothpaste; and has been found in human blood, breast milk, and urine. Interleukin (IL)-6 and IL-1 beta (IL-1β) are pro-inflammatory cytokines regulating cell growth, tissue repair, and immune function; increased levels of each have been associated with many diseases, including cancer. Previous studies showed that TCS at concentrations between 0.05 and 5µM consistently increased the secretion of IL-1β and IL-6 from human immune cells within 24h of exposure. The current study demonstrates that this increase in secretion was not due simply to release of existing stores but was due to an increase in cellular production/levels (both secreted and intracellular levels) of each of these cytokines. Production of IL-1β and IL-6 was increased by exposure to one or more concentration of TCS at each length of exposure (10min, 30min, 6h, and 24h). TCS-induced stimulation of cytokine production was shown to be dependent on the mitogen-activated protein kinase (MAPK) p44/42 (ERK 1/2). It was also shown that these TCS-induced increases in IL-1β and IL6 production were accompanied by increased mRNA for IL-1β and IL-6. The ability of TCS to increase production indicates that rather than activating a self-limiting process of depleting cells of already existing stores of IL-1β or IL-6, TCS can stimulate a process that has the capacity to provide sustained production of these cytokines and thus may lead to chronic inflammation and its pathological consequences.

Sludge-based activated carbon from two municipal sewage sludge precursors for improved secondary wastewater-treatment discharge-effluent

This study investigated the use of sludge-based activated carbon (SBAC) sorbent as an integrated waste-to-resources approach for the removal of contaminants from wastewater. We measured the ability of SBAC sorbents from two types of municipal sewage sludge (SS) precursors (thickened waste SS “TWSS-SBAC” and biosolids “Bio-SBAC”) from a Canadian wastewater treatment plant (WWTP) to stabilise emerging contaminants (ECs) from precursor SS and to remove ECs from the discharged effluent. The ECs were from pharmaceutical and personal care products (PPCPs), including antibiotics, disinfectants, and antibacterial hand-sanitisers and soaps, which were commonly used during the COVID-19 (coronavirus disease of 2019) pandemic. We measured the removal efficacy of Bio-SBAC at two dosages (1 g/L and 10 g/L) and TWSS-SBAC at one dosage (1 g/L) via 30-min batch adsorption tests for eleven PPCPs at mean concentrations of 2–2337 ng/L in the discharged effluent, and compared the results with those of other techniques and sorbents reported in literature. At both dosages, Bio-SBAC removed PPCPs, including four blood regulator compounds that have been extensively used since the pandemic outbreak (furosemide, gemfibrozil, glyburide, and warfarin), with their levels decreasing below the detection limit. The percentage removal for ibuprofen, 2-hydroxy-ibuprofen, and naproxen were 91.6–99.8% using 1 g/L. The antimicrobial compounds triclosan and triclocarban were completely removed at both dosages. Ninety-nine percentage of bisphenol A was removed at 1 g/L dosage and was completely removed at 10 g/L. TWSS-SBAC showed similar performance as Bio-SBAC in removing PPCPs from the final effluent to improve the quality of wastewater discharged from a WWTP.

Occurrence and distribution of triclosan and its transformation products in Taihu Lake, China.

The transformation products of triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) may be more persistent and toxic than their parent compound, yet their occurrence in aquatic environments is poorly understood. In this study, we identified three transformation products in sediment samples from Taihu Lake and compared their concentrations with the parent compound triclosan. Triclosan in Taihu Lake was at low level, ranging from 0.086 to 1.1 ng/L in surface water and 0.0058-8.3 ng/g in sediments. The three detected transformation products included methyl triclosan, chlorinated triclosan derivatives, and methyl chlorinated triclosan derivatives. Those transformation products constituted 0.73-87.5% of the total triclosan (total triclosan is the sum of triclosan, methyl triclosan, chlorinated triclosan derivatives, and methyl chlorinated triclosan derivatives on a molar basis), indicating that the ecological risk of transformation products should be considered in addition to the parent compound. Different transformation products had distinct spatial distributions. Chlorinated triclosan derivatives had the highest concentration in samples from the northwest region (0.016-0.21 ng/g) of the lake and were positively correlated with triclosan, which may indicate the possible transformation from triclosan to chlorinated triclosan derivatives. Methyl triclosan and methyl chlorinated triclosan derivatives were generally higher in samples from the center of the lake (0.22-0.28 ng/g for methyl triclosan and 0.017-0.021 ng/g for methyl chlorinated triclosan derivatives, respectively), indicating the possible occurrence of in situ microbial methylation of triclosan and chlorinated triclosan derivatives and the accumulation of those methylated analogues in Taihu Lake.

Biodegradation of an antimicrobial compound triclosan under sulfate reducing condition

Triclosan is an antibacterial and antifungal agent that is present in many detergents and surgical cleaning treatment products. This antimicrobial compound is discharged from households and collected at the local sewage treatment plant. Because triclosan inhibits phospholipid biosynthesis, it affects the microbial population that perform waste degradation. Sewage treatment plants are the major reservoir of triclosan as the wastewater from various households are discharged and treated in the local sewage treatment plant. This study was conducted to determine whether triclosan degradation occurs in the anaerobic digester of the Thibodaux Sewage Treatment Plant. Bacterial enrichment cultures were developed under various electron acceptor conditions including nitrate-reducing, sulfate-reducing, and mixed electron acceptor condition. The results showed the bacterial consortia developed under various conditions were not inhibited by 100 ppm of triclosan. More than 96% of triclosan was removed in both co-metabolic and triclosan as the sole carbon source conditions under sulfate-reducing condition. The molecular analysis of the consortium showed wide biodiversity of bacteria in the consortium.

Water Quality and the Impact by Contaminants of Emerging Concern: The Case of Verde River in Campos Gerais

In this article, we report the results of the work carried out on the Verde River, a predominantly urban river located in the city of Ponta Grossa, Paraná, Brazil. Developed in three stages, it aimed to evaluate the water quality through physical-chemical parameters, the presence of caffeine as a chemical tracer, and the compound Triclosan (TCS), considered a pollutant of emerging concern. An attempt was made to identify possible polluting sources along the river. Samples were collected at 4 points from the spring region, with sampling upstream and downstream of a Sewage Treatment Plant (STP). The physical-chemical parameters were determined in situ, through portable analysers, as well as in the laboratory, in this case, through analyses using molecular absorption spectroscopy. For the determination of TCS and Caffeine, high-performance liquid chromatography (HPLC) was used, preceded by a pre-concentration step in the solid phase (SPE), and the techniques were implemented after validation. The physicochemical evaluations of the surface samples showed a decline in water quality after the STP. Mean total phosphorus concentrations of 1.0 mg·L-1 (±0.4), as well as dissolved oxygen (DO) levels below 5.0 mg·L-1 were verified downstream of the STP. Caffeine concentrations for Verde River were between 49.0 to 299.0 μg·L-1, verified upstream and downstream of the STP. The results demonstrated the relationship between the presence of caffeine and impaction, either by the input of raw sewage or by treated effluent. TCS was detected by chromatographic analysis, downstream of the STP, with an average concentration of 27.6 (±1.7) μg·L-1, noting that its presence was associated with the reactor maintenance procedure, with the STP in the process called bypass. Obtaining quality data from Verde River is important for the protection of the environment and affects the health of the population.

Occurrence and Safety Evaluation of Antimicrobial Compounds Triclosan and Triclocarban in Water and Fishes of the Multitrophic Niche of River Torsa, India.

Personal care product (PCP) chemicals have a greater chance of accumulation in the aquatic environments because of their volume of use. PCPs are biologically active substances that can exert an adverse effect on the ecology and food safety. Information on the status of these substances in Indian open water ecosystems is scarce. In this paper, we report the incidence of two synthetic antimicrobials, triclosan (TCS), including its metabolite methyl-triclosan (Me-TCS) and triclocarban (TCC) in Torsa, a transboundary river flowing through India. In water TCS and TCC were detected at levels exceeding their respective PNEC (Predictive No Effect Concentration). Both the compounds were found to be bioaccumulative in fish. TCS concentration (91.1-589µg/kg) in fish was higher than that of TCC (29.1-285.5µg/kg). The accumulation of residues of the biocides varied widely among fishes of different species, ecological niche, and feeding habits. Me-TCS could be detected in fishes and not in water. The environmental hazard quotient of both TCS and TCC in water indicated a moderate risk. However, the health risk analysis revealed that fishes of the river would not pose any direct hazard to human when consumed. This is the first report of the occurrence of these PCP chemicals in a torrential river system of the eastern Himalayan region.

Triclosan has a robust, yet reversible impact on human gut microbial composition in vitro.

The recent ban of the antimicrobial compound triclosan from use in consumer soaps followed research that showcased the risk it poses to the environment and to human health. Triclosan has been found in human plasma, urine and milk, demonstrating that it is present in human tissues. Previous work has also demonstrated that consumption of triclosan disrupts the gut microbial community of mice and zebrafish. Due to the widespread use of triclosan and ubiquity in the environment, it is imperative to understand the impact this chemical has on the human body and its symbiotic resident microbes. To that end, this study is the first to explore how triclosan impacts the human gut microbial community in vitro both during and after treatment. Through our in vitro system simulating three regions of the human gut; the ascending colon, transverse colon, and descending colon regions, we found that treatment with triclosan significantly impacted the community structure in terms of reduced population, diversity, and metabolite production, most notably in the ascending colon region. Given a 2 week recovery period, most of the population levels, community structure, and diversity levels were recovered for all colon regions. Our results demonstrate that the human gut microbial community diversity and population size is significantly impacted by triclosan at a high dose in vitro, and that the community is recoverable within this system.

The antibiotic resistance-free mammalian expression plasmid vector pPAL for development of third generation vaccines

DNA vaccines require a vector to replicate genes and express encoding antigens. Antibiotic resistance genes are often used as selection markers, which must not be released to the environment upon final product commercialization. For this reason, generation of antibiotic resistance-free vectors is imperative. The pPAL vector contains the cytomegalovirus enhancer and promoter for expression in mammalian cells and the E. coli fabI chromosomal gene as a selectable marker. The fabI gene encodes the enoyl-ACP reductase (FabI). The bacteriostatic compound triclosan is an inhibitor of this enzyme. Therefore, the selection of positive clones depends on the enzyme:inhibitor molar ratio. According to western blot analysis, the pPAL vector is functional for expression of the Leishmania infantum (Kinetoplastid: Trypanosomatidae) gene encoding for the protein kinase C receptor analog (LACK/p36) in the HEK293T human cell line transfected with pPAL-LACK. The fabI gene sequence contains a 210 bp CpG island, suggesting a potential role as an adjuvant of the antibiotic resistance-free pPAL vector. In fact, Th1 response induction levels against canine leishmaniasis only using pPAL-LACK was shown to be as strong as in previous strategies using a recombinant vaccinia virus in combination with standard mammalian expression plasmid vectors. In summary, the pPAL plasmid contains the essential elements for manipulation and expression of any cloned DNA sequence in prokaryotic and mammalian cells using an E. coli endogenous gene as a selectable marker, which also provides a long CpG island. This element enhances Th1 immune response against L. infantum infection in dogs using the gene encoding for the LACK antigen. Therefore, this antibiotic resistance-free plasmid is a vaccine vector actively participating in protection against canine leishmaniasis and may be potentially tested as a vaccine vector with other antigens against different pathogens.

Accumulation and sublethal effects of triclosan and its transformation product methyl-triclosan in the earthworm Eisenia andrei exposed to environmental concentrations in an artificial soil.

Municipal biosolids are increasingly used as a low-cost fertilizer in agricultural soil. Biosolids are contaminated by low concentrations (nanograms per gram dry wt range) of a large variety of organic contaminants, such as triclosan. The effect of exposure to low concentrations of organic contaminants on soil biota remains largely undocumented. We evaluated the sublethal effects of triclosan on the earthworm Eisenia andrei using an artificial soil amended with a nominal concentration of triclosan of 50 ng g-1 dry weight soil. Using a 56-d reproduction test, we monitored the effect of triclosan exposure on adult earthworm survival, growth, and reproduction. The bioaccumulation of triclosan in earthworm tissue (adults and juveniles) and degradation of triclosan were monitored. The genotoxicity of triclosan was evaluated using a comet assay (DNA damage) on adult earthworm coelomocytes. Exposure to a low concentration of triclosan had no significant effects on adult earthworm survival and DNA damage but significantly stimulated growth (p < 0.05) by 2-fold compared with controls. It also significantly affected E. andrei reproduction parameters (p < 0.05), as evidenced by an increase in the number of cocoons and juveniles and a decrease in the mean dry weight of juveniles. The bioaccumulation of triclosan in earthworms was moderate (bioaccumulation factor ∼2). In biosolid-borne trials, the bioaccumulation of methyl-triclosan in earthworm tissues was higher than that of the parent compound triclosan. We conclude that exposure to low concentrations of triclosan in artificial soil can significantly affect the growth and reproductive performance of earthworms (i.e., E. andrei). More research is required with natural soils to assess triclosan bioavailability for earthworms. Environ Toxicol Chem 2018;37:1940-1948. © 2018 SETAC.

A common antimicrobial additive increases colonic inflammation and colitis-associated colon tumorigenesis in mice.

Triclosan (TCS) is a high-volume chemical used as an antimicrobial ingredient in more than 2000 consumer products, such as toothpaste, cosmetics, kitchenware, and toys. We report that brief exposure to TCS, at relatively low doses, causes low-grade colonic inflammation, increases colitis, and exacerbates colitis-associated colon cancer in mice. Exposure to TCS alters gut microbiota in mice, and its proinflammatory effect is attenuated in germ-free mice. In addition, TCS treatment increases activation of Toll-like receptor 4 (TLR4) signaling in vivo and fails to promote colitis in Tlr4-/- mice. Together, our results demonstrate that this widely used antimicrobial ingredient could have adverse effects on colonic inflammation and associated colon tumorigenesis through modulation of the gut microbiota and TLR4 signaling. Together, these results highlight the need to reassess the effects of TCS on human health and potentially update policies regulating the use of this widely used antimicrobial.

Triclosan Is an Aminoglycoside Adjuvant for Eradication of Pseudomonas aeruginosa Biofilms.

One of the most important clinical obstacles in cystic fibrosis (CF) treatment is antibiotic treatment failure due to biofilms produced by Pseudomonas aeruginosa The ability of this pathogen to survive eradication by tobramycin and pathoadapt into a hyperbiofilm state leading to chronic infections is key to its success. Retrospective studies have demonstrated that preventing this pathoadaptation by improving eradication is essential to extend the lives of CF patients. To identify adjuvants that enhance tobramycin eradication of P. aeruginosa, we performed a high-throughput screen of 6,080 compounds from four drug-repurposing libraries. We identified that the Food and Drug Administration (FDA)-approved compound triclosan, in combination with tobramycin, resulted in a 100-fold reduction of viable cells within biofilms at 6 h, but neither compound alone had significant antimicrobial activity against biofilms. This synergistic treatment significantly accelerated the killing of biofilms compared to that with tobramycin treatment alone, and the combination was effective against 6/7 CF clinical isolates compared to tobramycin treatment alone, including a tobramycin-resistant strain. Further, triclosan and tobramycin killed persister cells, causing a 100-fold reduction by 8 h and complete eradication by 24 h. Triclosan also enhances tobramycin killing of multiple Burkholderia cenocepacia and Staphylococcus aureus clinical isolates grown as biofilms. Additionally, triclosan showed synergy with other aminoglycosides, such as gentamicin or streptomycin. Triclosan is a well-tolerated aminoglycoside adjuvant shown to be safe for human use that could improve the treatment of biofilm-based infections.

СИНТЕЗ НЕРОЗЧИННОГО АЗОБАРВНИКА ІЗ АНТИБАКТЕРІАЛЬНОЮ СКЛАДОВОЮ

To enter into the structure of insoluble azo dye the antibacterial substance of a wide spectrum of action and to investigate the spectral characteristics. Azo dyes are obtained by using diazo-compounds, synthesized from known azoamines by the reaction of azo coupling with triclosan in the role of azocompound. Electronic spectra for solutions of synthesized dyes were obtained using a spectrophotometer. The principal possibility of synthesizing a dye with an antibacterial component in its structure is shown. The obtained electronic spectra of synthesized dyes with the triclosan containment. The use of surfactants changes the shades of synthesized dyes. By changing the azoamines, it is possible to regulate the activity of the bactericidal preparation on the surface of the fabric and in the water environment in contact with the fiber. For the first time, an antibacterial substance with a wide spectrum of action was entered into the structure of an insoluble azo dye and the possibility of regulating bactericidal activity is marked. Azo dye with antibacterial component was synthesized. Electronic spectra of synthesized dyes with the triclosan compound were obtained.

U.S. FDA halts use of triclosan in health care antiseptics

The antibacterial compound triclosan, already banned in the U.S. from consumer soaps, will no longer be allowed in antiseptic products used in hospitals and other health care settings. The U.S. Food & Drug Administration late last month deemed triclosan and 23 other antiseptic ingredients to not be generally recognized as safe and effective. “There was a lack of sufficient safety and efficacy data” for the 24 affected chemicals, explains FDA Commissioner Scott Gottlieb. The new regulation affects hand washes and rubs used by health care professionals, surgical hand scrubs and rubs, and antiseptic preparations used on patients’ skin before injections or surgery. In the new regulation, FDA put off deciding whether six other ingredients are safe and effective in antiseptic health care products, giving manufacturers more time to provide data to the agency. These substances are two quaternary ammonium compounds, benzalkonium chloride and benzethonium chloride; chloroxylenol; ethyl alcohol; isopropyl alcohol;

Brush with care

Antimicrobials Many commercial toothpastes contain the antimicrobial compound triclosan, which helps to reduce plaque and gum bleeding. Han et al. show that the nylon brushes and elastomer plastic of the toothbrush head absorb triclosan from the toothpaste during brushing and release it again during

Study of the mechanism of permeabilization of lecithin liposomes and rat liver mitochondria by the antimicrobial drug triclosan

The effect of the antimicrobial compound triclosan (5-chloro-2′-(2,4-dichlorophenoxy)phenol) on the permeability of lecithin liposomes and rat liver mitochondria was studied. It was found that triclosan was able to increase nonspecific permeability of liposomes in a dose-dependent manner, which was detected by the release of the fluorescent probe sulforhodamine B (SRB) from vesicles. A partial release of SRB occurs instantly at the moment of triclosan addition, which is followed by a slow leakage of the dye. The triclosan-induced release of SRB from liposomes grew as pH of the medium was decreased from 9.5 to 7.5. As revealed by the laurdan generalized polarization (GP) technique, triclosan increased laurdan GP in lecithin liposomes, indicating a decrease in membrane fluidity. Measurements of GP as a function of fluorescence excitation wavelength gave an ascending line for triclosan-containing liposomes, which can be interpreted as phase heterogeneity of the lipid/triclosan system. Dynamic light scattering experiments also showed that at a high triclosan-to-lipid molar ratio (~0.5), a population of smaller light-scattering particles (~0.4 of the size of liposomes) appear in the system. Experiments with rat liver mitochondria demonstrated that triclosan (10–70μM) induced a high-amplitude cyclosporin А-insensitive swelling of the organelles accompanied the release of cytochrome c. On the basis of the results obtained, possible mechanisms of the toxic effect of triclosan in eukaryotic cells are discussed.

Topical application of the anti-microbial chemical triclosan induces immunomodulatory responses through the S100A8/A9-TLR4 pathway

The anti-microbial compound triclosan is incorporated into numerous consumer products and is detectable in the urine of 75% of the general United States population. Recent epidemiological studies report positive associations with urinary triclosan levels and allergic disease. Although not sensitizing, earlier studies previously found that repeated topical application of triclosan augments the allergic response to ovalbumin (OVA) though a thymic stromal lymphopoietin (TSLP) pathway in mice. In the present study, early immunological effects following triclosan exposure were further evaluated following topical application in a murine model. These investigations revealed abundant expression of S100A8/A9, which reportedly acts as an endogenous ligand for Toll-like Receptor 4 (TLR4), in skin tissues and in infiltrating leukocytes during topical application of 0.75–3.0% triclosan. Expression of Tlr4 along with Tlr1, Tlr2 and Tlr6 increased in skin tissues over time with triclosan exposure; high levels of TLR4 were expressed on skin-infiltrating leukocytes. In vivo antibody blockade of the TLR4/MD-2 receptor complex impaired local inflammatory responses after four days, as evidenced by decreased Il6, Tnfα, S100a8, S100a9, Tlr1, Tlr2, Tlr4 and Tlr6 expression in the skin and decreased lymph node cellularity and production of IL-4 and IL-13 by lymph node T-cells. After nine days of triclosan exposure with TLR4/MD-2 blockade, impaired T-helper cell type 2 (TH2) cytokine responses were sustained, but other early effects on skin and lymph node cellularity were lost; this suggested alternative ligands/receptors compensated for the loss of TLR4 signaling. Taken together, these data suggest the S100A8/A9-TLR4 pathway plays an early role in augmenting immunomodulatory responses with triclosan exposure and support a role for the innate immune system in chemical adjuvancy.

Effects of triclosan on bacterial community composition and Vibrio populations in natural seawater microcosms.

Pharmaceuticals and personal care products, including antimicrobials, can be found at trace levels in treated wastewater effluent. Impacts of chemical contaminants on coastal aquatic microbial community structure and pathogen abundance are unknown despite the potential for selection through antimicrobial resistance. In particular, Vibrio, a marine bacterial genus that includes several human pathogens, displays resistance to the ubiquitous antimicrobial compound triclosan. Here we demonstrated through use of natural seawater microcosms that triclosan (at a concentration of ~5 ppm) can induce a significant Vibrio growth response (68–1,700 fold increases) in comparison with no treatment controls for three distinct coastal ecosystems: Looe Key Reef (Florida Keys National Marine Sanctuary), Doctors Arm Canal (Big Pine Key, FL), and Clam Bank Landing (North Inlet Estuary, Georgetown, SC). Additionally, microbial community analysis by 16 S rRNA gene sequencing for Looe Key Reef showed distinct changes in microbial community structure with exposure to 5 ppm triclosan, with increases observed in the relative abundance of Vibrionaceae (17-fold), Pseudoalteromonadaceae (65-fold), Alteromonadaceae (108-fold), Colwelliaceae (430-fold), and Oceanospirillaceae (1,494-fold). While the triclosan doses tested were above concentrations typically observed in coastal surface waters, results identify bacterial families that are potentially resistant to triclosan and/or adapted to use triclosan as a carbon source. The results further suggest the potential for selection of Vibrio in coastal environments, especially sediments, where triclosan may accumulate at high levels.

Occurrence and risk assessment of parabens and triclosan in surface waters of southern Brazil: a problem of emerging compounds in an emerging country

ABSTRACT Parabens and triclosan compounds are widely used in pharmaceutical products, personal care, food and various products of daily use. After use, the final destinations of these contaminants are domestic effluents and the environment if not collected or treated. The objective of this study was to evaluate the presence of parabens and triclosan in environments in a subtropical region, more specifically in the metropolitan region of Curitiba (southern Brazil) and possible effects of these compounds in aquatic environments through risk assessment through the use of risk quotient (RQ). Samples were collected in 20 points for 4 campaigns. For the extraction of the compounds we used the extraction technique of solid phase extraction (SPE). The determination of the compounds was using gas chromatography coupled to mass spectrometry (GC-MS). It was observed high concentrations of parabens, especially MeP (up to 2875 ng L–1). Despite high concentrations of parabens, their presence has a low risk to aquatic organisms. Triclosan has been observed at higher concentrations (415 ng L–1), suggesting once again that these environments are impacted by human action. The RQ assessed that triclosan has a high risk for certain groups of organisms.

Using antimicrobials with care

Microbiome Many soaps and other household products contain the antimicrobial compound triclosan. In a Perspective, Yee and Gilbert highlight recent animal studies showing that triclosan can alter the composition of the microbiota of fish and rats. It remains unclear whether triclosan has a negative effect on the human microbiota at the concentrations that are used in domestic settings. Triclosan and other antimicrobial agents are used at high concentrations in hospital settings, where most children in developed countries are born. This may be of concern because infant microbiomes are particularly vulnerable to disturbance, with potentially long-term consequences for growth and development. Science , this issue p. [348][1] [1]: /lookup/doi/10.1126/science.aag2698