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2,113 result(s) for "Sulfonates"
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Toxicity Evaluation of Household Detergents and Surfactants Using Zebrafish
There are concerns regarding the toxicity of household detergents to humans and aquatic organisms. There are various types of surfactants, which are the main components of detergents, and each detergent product has a different formulation. Therefore, high-throughput technologies capable of analyzing a large number of samples rapidly and accurately are required for research on detergent toxicity. In this study, image analysis techniques were used to quantify the locomotor activities from captured images using larval zebrafish (Danio rerio). When the 135-min time-lapse imaging was completed, the damage to the body of the animals was examined using a microscope. Additionally, we determined the animal survival and LC50. Nonionic decyl glucoside (APG-C10), one of the alkyl polyglucosides (APGs), exhibited the lowest toxicity, whereas linear alcohol ethoxylate (LA-9) exhibited the highest toxicity. AOS (α-olefin sulfonate), LAS (linear alkylbenzene sulfonate), and APG-600 showed moderate toxicity between LA-9 and APG-C10. Commercial detergents exhibited various degrees of toxicity, and there was a linear relationship (R2 = 0.776) between locomotor activity and survival percentage of animals.
Per- and polyfluoroalkyl substances (PFAS) and immune system-related diseases: results from the Flemish Environment and Health Study (FLEHS) 2008–2014
BackgroundThe successive FLEHS campaigns assess internal exposure to pollutants and associated early biological and health effects in participants of different age groups.Materials and methodsMother–newborn pairs (N = 220 in 2008–2009, age 18–42 years; N = 269 in 2013–2014, age 18–44 years), 197 adolescents 14–15 years (2010–2011), 201 adults 20–40 years (2008–2009) and 205 adults 50–65 years (2014) were recruited. For the various groups of subjects different sets of PFAS were assessed. Perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorobutane sulfonate (PFBS) were determined in cord plasma and peripheral serum as these were the PFAS compounds for which we had access to high quality measurements and which were expected to be present in the highest concentrations. Participants filled out a questionnaire based on the European Community Respiratory Health Survey questionnaire on asthma and allergy. In these cross-sectional studies associations were assessed using stepwise multiple logistic regression, with confounders (including smoking and familial occurrence of the disease) and potential covariates selected on the basis of experience in our previous studies and a literature search. Forest plots of odds ratios summarize the associations between the various PFAS on the one hand and the different immune outcomes on the other hand.ResultsFor several self-reported immune system-related diseases inverse associations with PFAS serum concentrations were observed. These inverse associations were more pronounced in mothers and adults than in adolescents. A significant inverse association was observed in adults and mothers (for mothers based on measurements on cord plasma) between PFNA, PFOS, and PFHxS and asthma (for mothers also for PFOA), in mothers between PFHxS, PFNA and PFOS and allergic rhinitis, in mothers and adults between PFHxS and PFOS and some forms of allergy (for mothers also for PFOA), in adults between PFOA and eczema, and in adolescents between PFOS and systemic allergy.ConclusionInternal exposure to PFAS was associated with changes in immunological processes consistent with what has been reported in the literature. Whereas these changes were observed in many publications to be associated with adverse health effects, our findings suggest that they can also lead to inverse associations with certain immune system-related diseases.
The identification and performance assessment of dominant bacterial species during linear alkylbenzene sulfonate (LAS)-biodegradation in a bioelectrochemical system
The anionic surfactant linear alkylbenzene sulfonate (LAS) is a major chemical constituent of detergent formulation. Regarding the recalcitrant nature of sulfonoaromatic compounds, discharging these substances into wastewater collection systems is a real environmental issue. A study on LAS biodegradation based on bioelectrochemical treatment and in the form of developing a single-chamber microbial fuel cell with air cathode is reported in the present work. Pretreatment study showed LAS concentration of 60 ppm resulted in the highest anaerobic LAS removal of 57%; so, this concentration was chosen to run the MFC. After the sustained anodic biofilm was formed, LAS degradation rate during 4 days in MFC was roughly 76% higher than that in the serum bottle, which indicated the role of the bioelectrochemical process in improving anaerobic LAS removal. Additionally, through 16S rRNA gene sequencing, the dominant bacterial species in the biofilm was identified as Pseudomonas zhaodongensis NEAU-ST5-21(T) with about 98.9% phylogenetic similarity and then a pathway was proposed for LAS anaerobic biodegradation. The MFC characteristics were assessed by pH monitoring as well as scanning electron microscopy and current density evolution.Graphic abstract
Effectivenes of Hanjali plant (Coix lacryma-jobi) in absorpting linear alkylbenzene sulfonates (LAS) pollutants
Water is an essential need for living things on earth. The increasing population causes the availability of clean water to decrease. This is caused by the high level of water pollution by waste, including domestic waste such as detergent (LAS). Various methods can be used to overcome water pollution, including phytoremediation techniques. One of the aquatic plants as a phytoremediation agent is the Coix lacryma-jobi plant. This study aims to examine the effectiveness of the ability of the Coix lacryma-jobi plant to absorb LAS. The method used is an experimental method using a Completely Randomized Design (CRD) with 5 treatments and 4 replications (plant control; LAS 4 mg/L; LAS 8 mg/L; LAS 16 mg/L; LAS 32 mg/L; LAS 64 mg/L with a detention time of 15 days. The results showed that hanjali plants were effective in absorbing LAS with the highest removal capacity of 94% in water contaminated with LAS 4 mg/L. The temperature and pH values fluctuated and the TDS value increased along with the increase in LAS concentration. Therefore, this plant can be said to be effective in absorbing LAS pollutants.
Surfactants in aquatic and terrestrial environment: occurrence, behavior, and treatment processes
Surfactants belong to a group of chemicals that are well known for their cleaning properties. Their excessive use as ingredients in care products (e.g., shampoos, body wash) and in household cleaning products (e.g., dishwashing detergents, laundry detergents, hard-surface cleaners) has led to the discharge of highly contaminated wastewaters in aquatic and terrestrial environment. Once reached in the different environmental compartments (rivers, lakes, soils, and sediments), surfactants can undergo aerobic or anaerobic degradation. The most studied surfactants so far are linear alkylbenzene sulfonate (LAS), quaternary ammonium compounds (QACs), alkylphenol ethoxylate (APEOs), and alcohol ethoxylate (AEOs). Concentrations of surfactants in wastewaters can range between few micrograms to hundreds of milligrams in some cases, while it reaches several grams in sludge used for soil amendments in agricultural areas. Above the legislation standards, surfactants can be toxic to aquatic and terrestrial organisms which make treatment processes necessary before their discharge into the environment. Given this fact, biological and chemical processes should be considered for better surfactants removal. In this review, we investigate several issues with regard to: (1) the toxicity of surfactants in the environment, (2) their behavior in different ecological systems, (3) and the different treatment processes used in wastewater treatment plants in order to reduce the effects of surfactants on living organisms.
Maternal Concentrations of Polyfluoroalkyl Compounds during Pregnancy and Fetal and Postnatal Growth in British Girls
Background: Prenatal exposures to polyfluoroalkyl compounds (PFCs) may be associated with adverse changes in fetal and postnatal growth. Objective: We explored associations of prenatal serum concentrations of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorohexane sulfonate (PFHxS) with fetal and postnatal growth in girls. Methods: We studied a sample of 447 singleton girls and their mothers participating in the Avon Longitudinal Study of Parents and Children (ALSPAC). Data on weight and length were obtained at birth and at 2, 9, and 20 months. Serum samples were obtained in 1991—1992, from mothers during pregnancy. We explored associations between prenatal PFC concentrations and weight at birth as well as longitudinal changes in weight-for-age SD scores between birth and 20 months. Results: PFOS (median, 19.6 ng/mL), PFOA (median, 3.7 ng/mL), and PFHxS (median, 1.6 ng/mL) were detected in 100% of samples. On average, girls born to mothers with prenatal concentrations of PFOS in the upper tertile weighed 140 g less [95% confidence interval (CI): -238, -42] at birth than girls born to mothers with concentrations in the lower tertile in adjusted models. Similar patterns were seen for PFOA (-133 g; 95% CI: -237, -30) and PFHxS (-108 g; 95% CI: -206, -10). At 20 months, however, girls born to mothers with prenatal concentrations of PFOS in the upper tertile weighed 580 g more (95% CI: 301, 858) when compared with those in the lower tertile. No differences in weight were found for PFOA and PFHxS. Conclusions: Girls with higher prenatal exposure to each of the PFCs examined were smaller at birth than those with lower exposure. In addition, those with higher exposure to PFOS were larger at 20 months.
Micropollutant Removal from Laundry Wastewater in Algal-Activated Sludge Systems: Microbial Studies
The main objective of this research was to study the feasibility of using algal and algal-activated sludge systems in treating laundry wastewater. Three different types of systems—green microalgae (system A), diatoms + activated sludge (system B), and green microalgae + activated sludge (system C)—were studied at six different solid retention times (SRT)—6, 8, 10, 12, 14, and 16 days—to evaluate their performance in removal of total organic carbon (TOC), total nitrogen (TN), anionic surfactants, and micropollutants with added trace elements. System B showed relatively better performance in removal of TOC (79%) and TN (90%). A total of 64 compounds were detected in influent when analyzed by LC-MS, of which 19 were grouped under herbicides, pesticides, and insecticides, 25 under pharmaceuticals, and 20 under others. Linear alkylbenzene sulfonate (LAS) was detected only in the effluent of system A and was not detected in both system B and system C. Grotan OX, an anti-microbial, was the compound with least removal in all the systems. The bacterial LAS degrader/tolerant plate count in system B at 16-day SRT was 2000 CFU/mL, 50 times more than the plate count of system C (40 CFU/mL). The LAS degrader/tolerant bacterial species identified were Aeromonas caviae and Klebsiella pneumonia in both systems B and C. The LAS degrader/tolerant green microalgae plate count at 16-day SRT was 130 CFU/mL, whereas no LAS degrader/tolerant diatom colonies were observed.
Growth and antioxidant response in Spirodela polyrrhiza under linear alkylbenzene sulfonate, naphthalene and their joint stress
The synthetic organic surfactants linear alkylbenzene sulfonate (LAS) and polycyclic aromatic hydrocarbon naphthalene (NAP), two common organic pollutants, are frequently detected in freshwater environments. However, the combined ecotoxicological risks associated with these pollutants have not been fully elucidated. The present study investigated the effects of individual and combined treatments of LAS and NAP on the growth and physiological responses of Spirodela polyrrhiza . The results showed that LAS was the main compound toxic to S. polyrrhiza in a dose-dependent manner. The peroxidase (POD) enzyme and catalase (CAT) enzyme are the main antioxidant enzymes protecting S. polyrrhiza from LAS stress. When exposed to NAP stress alone, only slightly reversible damage was observed as the exposure time was extended (14 days). The antioxidant enzyme systems (including superoxide dismutase (SOD), CAT and POD) showed positive responses. Synergistic effects were induced with LAS-NAP mixtures (≥ 5 + 5 mg L −1 ), and LAS played a major toxic role. The POD enzyme was a sensitive protective enzyme in duckweed during the joint exposure to LAS + NAP. The results indicate that LAS or NAP may cause serious damage to S. polyrrhiza and aggravate ecotoxicity in aquatic ecosystems .
Half-lives of PFOS, PFHxS and PFOA after end of exposure to contaminated drinking water
BackgroundMunicipal drinking water contaminated with perfluorinated alkyl acids had been distributed to one-third of households in Ronneby, Sweden. The source was firefighting foam used in a nearby airfield since the mid-1980s. Clean water was provided from 16 December 2013.ObjectiveTo determine the rates of decline in serum perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), and their corresponding half-lives.MethodsUp to seven blood samples were collected between June 2014 and September 2016 from 106 participants (age 4–84 years, 53% female).ResultsMedian initial serum concentrations were PFHxS, 277 ng/mL (range 12–1660); PFOS, 345 ng/mL (range 24–1500); and PFOA, 18 ng/mL (range 2.4–92). The covariate-adjusted average rates of decrease in serum were PFHxS, 13% per year (95% CI 12% to 15%); PFOS, 20% per year (95% CI 19% to 22%); and PFOA, 26% per year (95% CI 24% to 28%). The observed data are consistent with a first-order elimination model. The mean estimated half-life was 5.3 years (95% CI 4.6 to 6.0) for PFHxS, 3.4 years (95% CI 3.1 to 3.7) for PFOS and 2.7 years (95% CI 2.5 to 2.9) for PFOA. The interindividual variation of half-life was around threefold when comparing the 5th and 95th percentiles. There was a marked sex difference with more rapid elimination in women for PFHxS and PFOS, but only marginally for PFOA.ConclusionsThe estimated half-life for PFHxS was considerably longer than for PFOS and PFOA. For PFHxS and PFOS, the average half-life is shorter than the previously published estimates. For PFOA the half-life is in line with the range of published estimates.
Nickel-catalyzed electrochemical carboxylation of unactivated aryl and alkyl halides with CO2
Electrochemical catalytic reductive cross couplings are powerful and sustainable methods to construct C−C bonds by using electron as the clean reductant. However, activated substrates are used in most cases. Herein, we report a general and practical electro-reductive Ni-catalytic system, realizing the electrocatalytic carboxylation of unactivated aryl chlorides and alkyl bromides with CO 2 . A variety of unactivated aryl bromides, iodides and sulfonates can also undergo such a reaction smoothly. Notably, we also realize the catalytic electrochemical carboxylation of aryl (pseudo)halides with CO 2 avoiding the use of sacrificial electrodes. Moreover, this sustainable and economic strategy with electron as the clean reductant features mild conditions, inexpensive catalyst, safe and cheap electrodes, good functional group tolerance and broad substrate scope. Mechanistic investigations indicate that the reaction might proceed via oxidative addition of aryl halides to Ni(0) complex, the reduction of aryl-Ni(II) adduct to the Ni(I) species and following carboxylation with CO 2 . Electrochemistry is a promising approach to make existing chemical protocols milder, but many simple transformations of feedstocks are still out of reach. Here, the authors transform unactivated aryl and alkyl (pseudo)halides into carboxylic acids, via nickel catalysis and electricity, using atmospheric CO 2 as the carbon source.