Green adsorbents for pharmaceutics removal from urine: Analysis of isotherms, kinetics, adsorption interactions, cost estimation, and environmental impact

Husks of rice (RH), coffee (CH), and cholupa (CLH) were used to produce natural adsorbents. The natural adsorbents were used to remove pharmaceuticals such as diclofenac, ciprofloxacin, and acetaminophen in a mixture of distilled water. However, CH stood out for its efficiency in removing ciprofloxacin (74%) due to the higher concentration of acidic groups, as indicated by the Boehm method. In addition, CH removed 86% of ciprofloxacin individually. Therefore, CH was selected and used to remove other fluoroquinolones, such as levofloxacin and Norfloxacin. Although electrostatic interactions favored removals, better removal was observed for ciprofloxacin due to its smaller molecular volume. Then, ciprofloxacin was selected, and the effect of pH, matrix, and adsorbent doses were evaluated. In this way, using a pH of 6.2 in urine with a dose of 1.5 g L-1, it is possible to adsorb CIP concentrations in the range (0.0050-0.42 mmol L-1). Subsequently, the high R2 values and low percentages of APE and Δq indicated better fits for pseudo-second-order kinetics, suggesting a two-stage adsorption. At the same time, the Langmuir isotherm recommends a monolayer adsorption with a Qm of 25.2 mg g-1. In addition, a cost of 0.373 USD/g CIP was estimated for the process, where the material can be reused up to 4 times with a CIP removal in the urine of 51%. Consequently, thermodynamics analysis showed an exothermic and spontaneous process with high disorder. Furthermore, changes in FTIR analysis after adsorption suggest that CH in removing CIP in urine involves electrostatic attractions, hydrogen bonds and π-π interactions. In addition, the life cycle analysis presents, for the 11 categories evaluated, a lower environmental impact of the CIP removal in urine with CH than for the preparation of adsorbent, confirming that the adsorption process is more environmentally friendly than materials synthesis or other alternatives of treatments. Furthermore, future directions of the study based on real applications were proposed.

High-resolution mass spectrometry identifies delayed biomarkers for improved precision in acetaminophen/paracetamol human biomonitoring

Paracetamol/acetaminophen (N-acetyl-p-aminophenol, APAP) is a top selling analgesic used in more than 600 prescription and non-prescription pharmaceuticals. To study efficiently some of the potential undesirable effects associated with increasing APAP consumption (e.g., developmental disorders, drug-induced liver injury), there is a need to improve current APAP biomonitoring methods that are limited by APAP short half-life. Here, we demonstrate using high-resolution mass spectrometry (HRMS) in several human studies that APAP thiomethyl metabolite conjugates (S-methyl-3-thioacetaminophen sulfate and S-methyl-3-thioacetaminophen sulphoxide sulfate) are stable biomarkers with delayed excretion rates compared to conventional APAP metabolites, that could provide a more reliable history of APAP ingestion in epidemiological studies. We also show that these biomarkers could serve as relevant clinical markers to diagnose APAP acute intoxication in overdosed patients, when free APAP have nearly disappeared from blood. Using in vitro liver models (HepaRG cells and primary human hepatocytes), we then confirm that these thiomethyl metabolites are directly linked to the toxic N-acetyl-p-benzoquinone imine (NAPQI) elimination, and produced via an overlooked pathway called the thiomethyl shunt pathway. Further studies will be needed to determine whether the production of the reactive hepatotoxic NAPQI metabolites is currently underestimated in human. Nevertheless, these biomarkers could already serve to improve APAP human biomonitoring, and investigate, for instance, inter-individual variability in NAPQI production to study underlying causes involved in APAP-induced hepatotoxicity. Overall, our findings demonstrate the potential of exposomics-based HRMS approach to advance towards a better precision for human biomonitoring.

Urinary paracetamol (4-acetaminophenol) and its isomer 2-acetaminophenol of Chinese pregnant women: Exposure characteristics and association with oxidative stress biomarkers

N-Acetyl-4-aminophenol (NA4AP, paracetamol/acetaminophen), a widely used pharmaceutical, is ubiquitous in urine samples of general population, raising concern about human health risks; oxidative stress is considered to be a mechanism for its toxicities. N-Acetyl-2-aminophenol (NA2AP) is an isomer of NA4AP; until now, few studies characterized exposure characteristics of NA4AP and NA2AP in pregnant women. In this work, NA4AP and NA2AP concentrations in urine samples (n = 2124) collected at three different trimesters were measured to examine their internal body burden among Chinese pregnant women (n = 708) and their associations with three oxidative stress biomarkers (OSBs, 8-OHG, 8-OHdG, and HNE-MA). NA4AP was detected in 100% of the urine samples (median concentration: 7.96 ng/mL); NA2AP was detected in 94.9% of them (median: 3.05 ng/mL). The intraclass correlation coefficients of their concentrations across three trimesters were poor (<0.4); correlations of NA4AP and NA2AP were weak (r: 0.15-0.23). Pregnant women who had higher household income or urine samples provided in summer (vs. winter) had higher concentrations of NA4AP. Pregnant women who had a college degree or above (vs. less than a high school education) had higher concentrations of NA2AP but urine samples provided in summer (vs. winter) had lower concentrations of NA2AP. The 95th percentile estimated daily intake of NA4AP (2,331 ng/kg-bw/d) based on averaged concentrations of the three trimesters was 40 times lower than the cRfD for NA4AP (2.33 vs. 93 μg/kg-bw/d). Urinary concentrations of NA4AP and NA2AP were associated with higher levels of the selected OSBs. For example, an interquartile range increase in NA4AP was associated with a 26.5% (95% CI: 23.6-29.6%) increase in 8-OHG, a 27.5% (95% CI: 23.8-31.3%) increase in 8-OHdG, and a 33.4% (95% CI: 24.7-42.7%) increase in HNE-MA (p < 0.05). This is the first study to measure their concentrations repeatedly over three trimesters, examine their exposure characteristics, and reveal their associations with the selected OSBs in pregnant women. Further studies are needed to identify non-intentional exposure sources of NA4AP, NA2AP, and another isomer of them (i.e., N-acetyl-3-aminophenol), as well as more health risks related to their exposure.

Comprehensive investigation of persistent and mobile chemicals and per- and polyfluoroalkyl substances in urine of flemish adolescents using a suspect screening approach

Persistent and mobile chemicals (PMs) and per- and polyfluoroalkyl substances (PFAS) are groups of chemicals that have received recent global attention due to their potential health effects on the environment and humans. In this study, exposure to a broad range of PMs and PFAS was investigated in Flemish adolescents' urine samples (n = 83) using a suspect screening approach. For this purpose, three sample preparation methods were evaluated, and a basic liquid-liquid extraction was optimized for urine analysis based on the extraction efficiency of PMs (53-80%) and PFAS (>70%). In total, 9 PMs were identified in urine samples at confidence levels (CL) 1-3 and, among them, acetaminophen, 4-aminophenol, 2,2,6,6-tetramethyl-4-piperidone, trifluoroacetic acid (TFAA), sulisobenzone, ethyl sulfate, and 1,2-benzisothiazol-3(2H)-one 1,1-dioxide were confirmed at CL 1 and 2. In addition, the detection and identification of 2,2,6,6-tetramethyl-4-piperidone, 4-aminophenol, TFAA, and m-(2,3-epoxypropoxy)-N,N-bis(2,3-epoxypropyl) aniline (CL 3), has been reported for the first time in human urine in this study. For PFAS, only 2 compounds were identified at CL 4, implying that urine is not a suitable matrix for suspect screening of such compounds. A significant difference between sexes was observed in the detection rate of identified PMs, in particular for acetaminophen, 4-aminophenol, and sulisobenzone. The findings of this study can be used in future human biomonitoring programs, such as by including the newly identified compounds in quantitative methods or monitoring in other human matrices (e.g., serum).

Combined exposures to bisphenols, polychlorinated dioxins, paracetamol, and phthalates as drivers of deteriorating semen quality

BACKGROUND

Semen quality in men continues to decline in Western countries, but the contours of the issue remain obscure, in relation to contributing chemicals.

OBJECTIVES

To obtain more clarity about the chemicals that drive the deterioration of semen quality, we conducted a mixture risk assessment based on European exposures.

METHODS

We included chemicals capable of affecting semen quality after prenatal exposures, among them androgen receptor antagonists, substances that disrupt prostaglandin signalling, suppress testosterone synthesis, inhibit steroidogenic enzymes or activate the aryl hydrocarbon receptor. We employed the Hazard Index approach (HI), based on risk quotients of exposures in Europe and reference doses for reductions in semen quality. By summing up the risk quotients of the 29 chemicals included in the assessment we examined fold-exceedances of "acceptable" mixture exposures relative to an index value of 1. For bisphenols A, F, S, phthalates DEHP, DnBP, BBzP, DiNP, n-butyl paraben and paracetamol we relied on biomonitoring studies in which these 9 chemicals were measured together in the same subjects. This allowed us to construct personalised Hazard Indices.

RESULTS

Highly exposed subjects experienced combined exposures to the 9 chemicals that exceeded the index value of 1 by more than 100-fold; the median was a 17-fold exceedance. Accounting for median background exposures to the remaining 20 chemicals added a Hazard Index of 1.39. Bisphenol A made the largest contribution to the HI, followed by polychlorinated dioxins, bisphenols S and F and DEHP. Eliminating bisphenol A alone would still leave unacceptably high mixture risks. Paracetamol is also a driver of mixture risks among subjects using the drug.

CONCLUSIONS

Tolerable exposures to substances associated with deteriorations of semen quality are exceeded by a large margin. Bisphenols, polychlorinated dioxins, phthalates and analgesics drive these risks. Dedicated efforts towards lowering exposures to these substances are necessary to mitigate risks.

Aniline exposure activates receptor-interacting serine/threonineprotein kinase 1 and causes necroptosis of AML12 cells

With the increased use of aniline, potential impacts on human health cannot be ignored. The hepatotoxicity of aniline is largely unknown and the underlying mechanism remains unclear. Therefore, the aim of the present study was to investigate the hepatotoxicity of aniline and elucidate the underlying mechanism. AML12 cells were exposed to different concentrations of aniline (0, 5, 10, or 20 mM) to observe changes to reactive oxygen species (ROS) production and the expression patterns of necroptosis-related proteins (RIPK1, RIPK3, and MLKL). The potential mechanism underlying aniline-induced hepatotoxicity was explored by knockout of RIPK1. The results showed that aniline induced cytotoxicity in AML12 cells in a dose-dependent manner in addition to the production of ROS and subsequent necroptosis of AML12 cells. Silencing of RIPK1 reversed upregulation of necroptosis-related proteins in AML12 cells exposed to aniline, demonstrating that aniline-induced ROS production was related to necroptosis of AML12. Moreover, aniline promoted intracellular RIPK1 activation, suggesting that the RIPK1/ROS pathway plays an important role in aniline-induced hepatotoxicity. NAC could quench ROS and inhibit necroptosis. These results provide a scientific basis for future studies of aniline-induced hepatotoxicity for the prevention and treatment of aniline-induced cytotoxicity.

Maternal Paracetamol Intake During Pregnancy-Impacts on Offspring Reproductive Development

Paracetamol (acetaminophen) is the preferred antipyretic/analgesic for pregnant women as it is believed there are no adverse fetal effects at the recommended dose. However, emerging evidence suggests that intrauterine paracetamol exposure may be associated with certain urogenital/reproductive disorders in the offspring. In this mini-review, we describe human fetal sex development and possible pharmacological mechanisms by which paracetamol may disrupt this process, including reduced testicular production of testosterone and/or insulin-like peptide 3. We then review the available epidemiological literature on associations between maternal paracetamol exposure and offspring sexual development. Three epidemiological studies have reported associations between maternal paracetamol intake and increased risk of cryptorchidism, although five others have not. None have found associations with hypospadias or penile length. Two out of three studies have reported a shorter anogenital distance (a marker of androgen action during the masculinisation programming window, ∼8-14 weeks of gestation) in male infants antenatally exposed to paracetamol. One study has described a dose-dependent relationship between maternal paracetamol consumption and earlier female (but not male) attainment of puberty. Such epidemiological analyses are complicated by various factors, including method of paracetamol exposure assessment (usually retrospective self-report), variation in diagnostic accuracy, selection bias, confounding by clinical indication, and demographic/genetic differences between geographically separated populations. There is an urgent need for stronger evidence in this area, from both relevant experimental studies and large, carefully-designed prospective studies. In the meantime, a precautionary attitude to gestational paracetamol usage should be considered as the evidence for clinically significant reproductive effects in humans is limited.

Using Experimental Models to Decipher the Effects of Acetaminophen and NSAIDs on Reproductive Development and Health

Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin (acetylsalicylic acid), diclofenac and ibuprofen (IBU), and analgesic drugs, such as acetaminophen (APAP, or paracetamol), are widely used to treat inflammation and pain. APAP and IBU are over-the-counter drugs and are among the most commonly taken drugs in the first trimester of pregnancy, even in combination. Furthermore, these drugs and their metabolites are released in the environment, and can be frequently detected in wastewater, surface water, and importantly in drinking water. Although their environmental concentrations are much lower than the therapeutics doses, this suggests an uncontrolled low-dose exposure of the general population, including pregnant women and young children, two particularly at risk populations. Epidemiological studies show that exposure to these molecules in the first and second trimester of gestation can favor genital malformations in new-born boys. To investigate the cellular, molecular and mechanistic effects of exposure to these molecules, ex vivo studies with human or rodent gonadal explants and in vivo experiments in rodents have been performed in the past years. This review recapitulates recent data obtained in rodent models after in utero or postnatal exposure to these drugs. The first part of this review discusses the mechanisms by which NSAIDs and analgesics may impair gonadal development and maturation, puberty development, sex hormone production, maturation and function of adult organs, and ultimately fertility in the exposed animals and their offspring. Like other endocrine disruptors, NSAIDs and APAP interfere with endocrine gland function and may have inter/transgenerational adverse effects. Particularly, they may target germ cells, resulting in reduced quality of male and female gametes, and decreased fertility of exposed individuals and their descendants. Then, this review discusses the effects of exposure to a single drug (APAP, aspirin, or IBU) or to combinations of drugs during early embryogenesis, and the consequences on postnatal gonadal development and adult reproductive health. Altogether, these data may increase medical and public awareness about these reproductive health concerns, particularly in women of childbearing age, pregnant women, and parents of young children.

Selective degradation of acetaminophen from hydrolyzed urine by peroxymonosulfate alone: performances and mechanisms

Owing to the high concentration of pharmaceuticals in urine, the degradation of these organic pollutants before their environmental release is highly desired. Peroxymonosulfate (PMS) is a desirable oxidant that can be applied to environmental remediation; however, the performance and mechanism of PMS for the degradation of pharmaceuticals in the urine matrix have not been investigated. Herein, PMS was first discovered to efficiently degrade typical pharmaceuticals in hydrolyzed urine (HU) by selecting acetaminophen (ACE) as a target compound. Quenching experiments revealed that singlet oxygen (1O2) and hydroxyl radicals (HO˙) were observed in the HU/PMS system, but the principal reactive species (RS) responsible for ACE removal was 1O2. The major constituents of HU, including SO4 2- and organics (creatine, creatinine and hippuric acid), hardly affected the elimination of ACE, whereas Cl-, H2PO4 - and NH4 + would accelerate ACE degradation. Besides, HCO3 - slightly inhibited this process. The ACE degradation efficiency was enhanced using photo-irradiation, including sunlight and visible light, although increasing the reaction temperature could, interestingly, hardly accelerate the degradation rate of ACE. Three-dimensional excitation-emission matrices (3D-EEMs) have indicated that other intermediates that have a higher fluorescence intensity might be generated in the HU/PMS system. Finally, nine intermediate products were determined and the degradation pathways of ACE were proposed. Overall, the results of this study illustrated that PMS is an efficient oxidant for the degradation of ACE in HU.

Paracetamol use during pregnancy - a call for precautionary action

Paracetamol (N-acetyl-p-aminophenol (APAP), otherwise known as acetaminophen) is the active ingredient in more than 600 medications used to relieve mild to moderate pain and reduce fever. APAP is widely used by pregnant women as governmental agencies, including the FDA and EMA, have long considered APAP appropriate for use during pregnancy when used as directed. However, increasing experimental and epidemiological research suggests that prenatal exposure to APAP might alter fetal development, which could increase the risks of some neurodevelopmental, reproductive and urogenital disorders. Here we summarize this evidence and call for precautionary action through a focused research effort and by increasing awareness among health professionals and pregnant women. APAP is an important medication and alternatives for treatment of high fever and severe pain are limited. We recommend that pregnant women should be cautioned at the beginning of pregnancy to: forego APAP unless its use is medically indicated; consult with a physician or pharmacist if they are uncertain whether use is indicated and before using on a long-term basis; and minimize exposure by using the lowest effective dose for the shortest possible time. We suggest specific actions to implement these recommendations. This Consensus Statement reflects our concerns and is currently supported by 91 scientists, clinicians and public health professionals from across the globe.

Use of paracetamol (acetaminophen) as a nonprescription analgesic and semen quality in young men: A cross-sectional study

BACKGROUND

Paracetamol (acetaminophen) is a frequently used nonprescription analgesic with suggested endocrine-disrupting properties. Epidemiological evidence on the effect of paracetamol on male fecundity is sparse.

OBJECTIVES

To investigate if the use of paracetamol as an oral nonprescription mild analgesic was associated with semen quality in young men.

MATERIALS AND METHODS

This cross-sectional study was based on data from the Fetal Programming of Semen Quality (FEPOS; 2017-2019) cohort of 1058 young men (18-21 years) included in the Danish National Birth Cohort. Participants completed a comprehensive online questionnaire on health behavior including analgesic use and provided a semen sample. Negative binomial regression models were used to estimate the percentage differences (adjusted mean ratios [aMR]) in semen quality characteristics according to paracetamol use (no; yes) and frequency of use (almost never; <1/month; ≥1/month; ≥1/week).

RESULTS

In total, 28% of the 913 participants with available data reported the use of paracetamol within the last 6 months. We found a slightly higher total sperm count (aMR 1.13 95% CI [0.99-1.30]) in users compared to nonusers but other semen characteristics were unaffected. The frequency of use was suggestive of lower total sperm count and morphologically normal sperm cells primarily among users ≥1/week, however, CIs were wide.

DISCUSSION

We were unable to account for the underlying reason for paracetamol use, which may induce confounding by indication. Exposure misclassification due to recall is likely but probably nondifferential due to the participants' young age and unawareness of semen quality. Due to the rapid plasma half-life of paracetamol and few frequent users, it was not possible to conclude on potential high-dose effects.

CONCLUSION

Our findings do not suggest any strong detrimental effect of paracetamol use on semen quality within this sample of young Danish men. However, the effects of high dose and frequent use cannot be excluded.

Paracetamol (Acetaminophen) and the Developing Brain

Paracetamol is commonly used to treat fever and pain in pregnant women, but there are growing concerns that this may cause attention deficit hyperactivity disorder and autism spectrum disorder in the offspring. A growing number of epidemiological studies suggests that relative risks for these disorders increase by an average of about 25% following intrauterine paracetamol exposure. The data analyzed point to a dose-effect relationship but cannot fully account for unmeasured confounders, notably indication and genetic transmission. Only few experimental investigations have addressed this issue. Altered behavior has been demonstrated in offspring of paracetamol-gavaged pregnant rats, and paracetamol given at or prior to day 10 of life to newborn mice resulted in altered locomotor activity in response to a novel home environment in adulthood and blunted the analgesic effect of paracetamol given to adult animals. The molecular mechanisms that might mediate these effects are unknown. Paracetamol has diverse pharmacologic actions. It reduces prostaglandin formation via competitive inhibition of the peroxidase moiety of prostaglandin H2 synthase, while its metabolite N-arachidonoyl-phenolamine activates transient vanilloid-subtype 1 receptors and interferes with cannabinoid receptor signaling. The metabolite N-acetyl-p-benzo-quinone-imine, which is pivotal for liver damage after overdosing, exerts oxidative stress and depletes glutathione in the brain already at dosages below the hepatic toxicity threshold. Given the widespread use of paracetamol during pregnancy and the lack of safe alternatives, its impact on the developing brain deserves further investigation.

Urinary concentrations of acetaminophen in young children in central and south China: Repeated measurements and associations with 8-hydroxy-guanosine and 8-hydroxy-2'-deoxyguanosine

Acetaminophen (AAP) is the most widely used over-the-counter analgesic in the world; it is also a metabolite of industrial chemical aniline. It may predispose individuals to oxidative stress. However, the exposure profile of AAP in the general population in China and the associations between AAP and oxidative stress biomarkers have scarcely been investigated. In this study, we determined the urinary concentrations of AAP and evaluated its associations with 8-hydroxy-guanosine (8-OHG) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), the most widely used biomarkers of nucleoside oxidation affecting RNA and DNA, in 393 urine samples collected from 131 healthy children (0-6.6 y) on three consecutive days from Wuhan, central China, and Shenzhen, south China. AAP was found in all urine samples, suggesting that exposure to AAP was ubiquitous in young children in central and south China. The median concentration of specific gravity (SG)-adjusted AAP was 9.21 ng/mL (range: 1.11-1 453 ng/mL). Good inter-day reproducibility was observed for SG-adjusted AAP concentrations (intraclass correlation coefficient, 0.75). The SG-adjusted urinary 8-OHdG and 8-OHG concentrations were positively correlated with AAP (β = 0.08; 95% confidence interval [95% CI]: 0.02-0.13, and β = 0.10; 95% CI: 0.04-0.15, respectively). The data indicated that AAP exposure might be associated with oxidative DNA and RNA damage in the general population with unintentional exposure. To our knowledge, this is the first report of AAP exposure in young healthy children in central and south China. This is also the first study to evaluate the inter-day variations in urinary AAP concentrations and to explore the associations between AAP exposure and oxidative stress biomarkers in the general population.

Acetaminophen metabolism revisited using non-targeted analyses: Implications for human biomonitoring

The analgesic paracetamol/acetaminophen (N-acetyl-4-aminophenol, APAP) is commonly used to relieve pain, fever and malaise. While sales have increased worldwide, a growing body of experimental and epidemiological evidence has suggested APAP as a possible risk factor for various health disorders in humans. To perform internal exposure-based risk assessment, the use of accurate and optimized biomonitoring methods is critical. However, retrospectively assessing pharmaceutical use of APAP in humans is challenging because of its short half-life. The objective of this study was to address the key issue of potential underestimation of APAP use using current standard analytical methods based on urinary analyses of free APAP and its phase II conjugates. The question we address is whether investigating additional metabolites than direct phase II conjugates could improve the monitoring of APAP. Using non-targeted analyses based on high-resolution mass spectrometry, we identified, in a controlled longitudinal exposure study with male volunteers, overlooked APAP metabolites with delayed formation and excretion rates. We postulate that these metabolites are formed via the thiomethyl shunt after the enterohepatic circulation as already observed in rodents. Importantly, these conjugated thiomethyl metabolites were (i) of comparable diagnostic sensitivity as the free APAP and its phase II conjugates detected by current methods; (ii) had delayed peak levels in blood and urine compared to other APAP metabolites and therefore potentially extend the window of exposure assessment; and (iii) provide relevant information regarding metabolic pathways of interest from a toxicological point of view. Including these metabolites in future APAP biomonitoring methods therefore provides an option to decrease potential underestimation of APAP use. Moreover, our data challenge the notion that the standard methods in biomonitoring based exclusively on the parent compound and its phase II metabolites are adequate for human biomonitoring of a non-persistent chemical such as APAP.

Three-dimensional voltammetry: Use of chronoamperometric E-t-i data to achieve second-order advantage

This work studied the use of three-dimensional voltammetry, particularly potential-time-current (E-t-i) data, on the development of electroanalytical methods. E-t-i data was obtained by taking chronoamperograms at potentials applied as pulses on a staircase waveform. By using this three-way kind of data and appropriate calibration algorithms, the possibility of achieving the second-order advantage was evaluated in the determination of ferrocyanide in the presence of the uncalibrated interference hydroquinone as a model system. The determination of acetaminophen in urine samples, where ascorbic acid and uric acid play the major roles as interferents was also studied. Parallel factor analysis (PARAFAC) and multivariate curve resolution alternating least-squares (MCR-ALS) were the algorithms employed in this work. Both algorithms successfully achieved the second-order advantage by correctly predicting the concentrations of the validation synthetic samples. Excellent predictions were obtained in the direct analysis of acetaminophen-spiked urine samples by E-t-i data and MCR-ALS.

Quantitative analysis of paracetamol, metacetamol, and orthocetamol in equine urine from racehorses in Japan using liquid chromatography-electrospray ionization-tandem mass spectrometry

Paracetamol is commonly used as an over-the-counter analgesic and antipyretic medication for humans, but not sold as a legitimate therapeutic medication for horses in Japan. However, paracetamol is commonly found in horses together with its two isomers, metacetamol and orthocetamol. We previously reported that paracetamol and orthocetamol were both present in selected feed consumed by Japanese racehorses. For the purpose of the doping control of paracetamol in local Japanese horses, we proposed establishing residue limits (Japanese residue limits, JRLs) to minimize the risk of reporting paracetamol from environmental contributions and to differentiate its presence from active administration. Recently, we proposed a preliminary JRL for paracetamol in equine plasma based on a population study of more than 300 Japanese racehorses. In this paper, we will present our studies on the urinary concentrations of paracetamol, metacetamol, and orthocetamol in postrace samples collected from 403 Japanese racehorses over a 1 year period, detected using liquid chromatography-electrospray ionization-tandem mass spectrometry. Our results revealed that the hydrolyzed urinary concentrations of paracetamol, metacetamol, and orthocetamol were in the range 15.7-2,360 ng/mL (median 363 ng/mL), 8.07-382 ng/mL (84.5 ng/mL), and 919-74,418 ng/mL (13,475 ng/mL), respectively. Based on our statistical model, the preliminary JRL of hydrolyzed paracetamol in equine urine was determined to be 7,400 ng/mL, at a risk factor of 1 in 10,000. Further investigations will be required to demonstrate the applicability and validity of our preliminary plasma and urine JRLs to local Japanese racehorses.

Effect of environmental and pharmaceutical exposures on fetal testis development and function: a systematic review of human experimental data

BACKGROUND

Overall, the incidence of male reproductive disorders has increased in recent decades. Testicular development during fetal life is crucial for subsequent male reproductive function. Non-genomic factors such as environmental chemicals, pharmaceuticals and lifestyle have been proposed to impact on human fetal testicular development resulting in subsequent effects on male reproductive health. Whilst experimental studies using animal models have provided support for this hypothesis, more recently a number of experimental studies using human tissues and cells have begun to translate these findings to determine direct human relevance.

OBJECTIVE AND RATIONALE

The objective of this systematic review was to provide a comprehensive description of the evidence for effects of prenatal exposure(s) on human fetal testis development and function. We present the effects of environmental, pharmaceutical and lifestyle factors in experimental systems involving exposure of human fetal testis tissues and cells. Comparison is made with existing epidemiological data primarily derived from a recent meta-analysis.

SEARCH METHODS

For identification of experimental studies, PubMed and EMBASE were searched for articles published in English between 01/01/1966 and 13/07/2018 using search terms including ‘endocrine disruptor’, ‘human’, ‘fetal’, ‘testis’, ‘germ cells’, ‘testosterone’ and related search terms. Abstracts were screened for selection of full-text articles for further interrogation. Epidemiological studies involving exposure to the same agents were extracted from a recent systematic review and meta-analysis. Additional studies were identified through screening of bibliographies of full-texts of articles identified through the initial searches.

OUTCOMES

A total of 25 experimental studies and 44 epidemiological studies were included. Consistent effects of analgesic and phthalate exposure on human fetal germ cell development are demonstrated in experimental models, correlating with evidence from epidemiological studies and animal models. Furthermore, analgesic-induced reduction in fetal testosterone production, which predisposes to the development of male reproductive disorders, has been reported in studies involving human tissues, which also supports data from animal and epidemiological studies. However, whilst reduced testosterone production has been demonstrated in animal studies following exposure(s) to a variety of environmental chemicals including phthalates and bisphenol A, these effects are not reproduced in experimental approaches using human fetal testis tissues.

WIDER IMPLICATIONS

Direct experimental evidence for effects of prenatal exposure(s) on human fetal testis development and function exists. However, for many exposures the data is limited. The increasing use of human-relevant models systems in which to determine the effects of environmental exposure(s) (including mixed exposures) on development and function of human tissues should form an important part of the process for assessment of such exposures by regulatory bodies to take account of animal–human differences in susceptibility.

Investigation of plasma concentrations of paracetamol, metacetamol, and orthocetamol in Japanese racehorses using liquid chromatography-electrospray ionisation-tandem mass spectrometry

Paracetamol is used widely as an over-the-counter analgesic and antipyretic medication for humans, but not for Japanese racehorses. Paracetamol can be an environmental substance, and is found together with its two isomers, metacetamol and orthocetamol, in equine urine. However, the sources and routes of paracetamol exposure remain unclear. To control the misuse of paracetamol, it is appropriate to establish residue limits for paracetamol to differentiate the administration of paracetamol from its environmental levels. In this study, we developed and validated a quantitative method for paracetamol, metacetamol, and orthocetamol in equine plasma using liquid chromatography-electrospray ionization-tandem mass spectrometry and applied it to postrace samples from 320 Japanese racehorses for approximately 1 year. In addition, we conducted feed analysis and related pharmacokinetics simulations to evaluate the contributions from exposure via feed. The hydrolyzed plasma concentrations of paracetamol, metacetamol, and orthocetamol ranged from 0.787 to 39.8 ng/mL (median 5.87 ng/mL), 0 to 2.13 ng/mL (0.347 ng/mL), and 1.98 to 82.8 ng/mL (16.6 ng/mL), respectively. Such low concentrations of paracetamol were deemed irrelevant to therapeutic effect. Based on statistical analysis, the preliminary Japanese residue limits of unhydrolyzed and hydrolyzed paracetamol were determined to be 70.5 ng/mL and 112 ng/mL, respectively, in plasma, at a risk factor of 1 in 10,000. Furthermore, we detected paracetamol and orthocetamol in feed samples. A pharmacokinetics simulation showed that the presence of orthocetamol is most probably related to daily feed rations. As for paracetamol, feed can be one of the sources and other possible sources require further investigation.

Consequences of analgesics use in early pregnancy: Results of tests on mice

Self-medication during pregnancy continues to be an issue in developing countries due to poor medical education. The most commonly used drugs are analgesics, mainly acetaminophen (paracetamol, APAP) and, to a lesser extent, ketoprofen (KPF). The aim of the study was to establish whether there are consequences of accidental use of these two drugs during early embryogenesis. The experimental study was performed on 30 pregnant white mice, divided into three groups: a first group to which APAP was administered, a second group to which KPF was administered, and group 3 as a control group. At delivery, the baby mice were examined, and after their first parturition, they were taken into study and examined according to the established protocol. Macroscopic and microscopic examinations of the liver and kidney were performed; liver and renal changes were recorded. Regarding the fertility, the number of fetuses born to mothers that were administered APAP and KPF corresponded to the normal values recorded in this species. Microscopic changes that were found in the kidney were as follows: APAP group - necrosis of the urinary tube, vascular congestions and vascular disorders; KPF group - ectasia, especially in the medullary cavity. Microscopic hepatic changes showed in the APAP group - vascular congestions, vascular disorders and hemosiderin deposits in the Kupffer cells; in the KPF group were found - discrete vascular disorders consisting in sinusoidal capillary ectasia and vascular congestions, as well as the presence of lymphocyte conglomerates. The aforementioned lesions indicate hepatic and renal distress with variable degrees of severity, but they appear to be reversible (the longer the time from the maximum effect of the drug the lower its toxicity).

Comparison of fetal growth by maternal prenatal acetaminophen use

BACKGROUND

Equivocal findings exist regarding prenatal acetaminophen use and various adverse neonatal and childhood health outcomes, though with no data on fetal growth. We evaluated whether fetal growth differed by maternal acetaminophen use.

METHODS

Racially diverse, healthy women with low-risk antenatal profiles from 12 US clinical centers were enrolled in a prospective cohort study and followed until delivery. Ultrasound measurements of fetal parameters and self-reported prenatal acetaminophen use were collected at enrollment and up to five follow-up visits. Prenatal acetaminophen use was dichotomized as none or any.

RESULTS

Among 2291 women, 932 (41%) reported the use of acetaminophen medications during the current pregnancy. Estimated growth curves of fetal parameters did not differ between women reporting use of any medication containing acetaminophen and women with no reported use of the same.

CONCLUSION

Among healthy mothers with low-risk pregnancies, maternal acetaminophen use was not associated with alterations in fetal growth.

Molecular Mechanism of Aniline Induced Spleen Toxicity and Neuron Toxicity in Experimental Rat Exposure: A Review

Aniline exposure leads to neuron and spleen toxicity specifically and makes diverse neurological effects and sar-coma that is defined by splenomegaly, hyperplasia, and fibrosis and tumors formation at the end. However, the molecular mechanism(s) of aniline-induced spleen toxicity is not understood well, previous studies have represented that aniline expo-sure results in iron overload and initiation of oxidative/nitrosative disorder stress and oxidative damage to proteins, lipids and DNA subsequently, in the spleen. Elevated expression of cyclins, cyclin-dependent kinases (CDKs) and phosphorylation of pRB protein along with increases in A, B and CDK1 as a cell cycle regulatory proteins cyclins, and reduce in CDK inhibitors (p21 and p27) could be critical in cell cycle regulation, which contributes to tumorigenic response after aniline exposure. Aniline-induced splenic toxicity is corre-lated to oxidative DNA damage and initiation of DNA glycosylases expression (OGG1, NEIL1/2, NTH1, APE1 and PNK) for removal of oxidative DNA lesions in rat. Oxidative stress causes transcriptional up-regulation of fibrogenic/inflammatory factors (cytokines, IL-1, IL-6 and TNF-α) via induction of nuclear factor-kappa B, AP-1 and redox-sensitive transcription factors, in aniline treated-rats. The upstream signalling events as phosphorylation of IκB kinases (IKKα and IKKβ) and mito-gen-activated protein kinases (MAPKs) could potentially be the causes of activation of NF-κB and AP-1. All of these events could initiate a fibrogenic and/or tumorigenic response in the spleen. The spleen toxicity of aniline is studied more and the different mechanisms are suggested. This review summarizes those events following aniline exposure that induce spleen tox-icity and neurotoxicity.

Prenatal exposure to acetaminophen and children's language development at 30 months

OBJECTIVE

To examine prenatal APAP exposure in relation to language development in offspring at 30 months of age.

METHOD

A population-based pregnancy cohort study including 754 women who enrolled in the Swedish Environmental Longitudinal, Mother and child, Asthma and allergy (SELMA) study in pregnancy week 8-13. Two exposure measures were used: (1) maternally reported number of APAP tablets taken between conception and enrollment; (2) APAP urinary concentration at enrollment. Language development at 30 months was assessed by nurse's evaluation and parental questionnaire, including the number of words the child used (<25, 25-50 and >50). Main study outcome; parental report of use of fewer than 50 words, termed language delay (LD).

RESULTS

59.2% of women enrolled in weeks 8-13 reported taking APAP between conception and enrollment. APAP was measurable in all urine samples and urinary APAP was correlated with the number of APAP taken during pregnancy (P<0.01). Language delay was more prevalent in boys (12.6%) than girls (4.1%) (8.5% in total). Both the number of APAP tablets and urinary APAP concentration were associated with greater LD in girls but not in boys. The adjusted odds ratio (OR) for LD among girls whose mothers reported >6 vs. 0 APAP tablets was 5.92 (95% confidence interval (CI) 1.10-31.94). The OR for LD in girls whose mothers' urinary APAP was in the highest compared to the lowest quartile was 10.34 (95% CI 1.37-77.86). While it cannot be ruled out, our available data do not support confounding by indication.

CONCLUSIONS

Given the prevalence of prenatal APAP use and the importance of language development, these findings, if replicated, would suggest that pregnant women should limit their use of this analgesic during pregnancy.

EDC IMPACT: Is exposure during pregnancy to acetaminophen/paracetamol disrupting female reproductive development?

Concern has been raised over chemical-induced disruption of ovary development during fetal life resulting in long-lasting consequences only manifesting themselves much later during adulthood. A growing body of evidence suggests that prenatal exposure to the mild analgesic acetaminophen/paracetamol can cause such a scenario. Therefore, in this review, we discuss three recent reports that collectively indicate that prenatal exposure in a period of 13.5 days post coitum in both rats and mouse can result in reduced female reproductive health. The combined data show that the exposure results in the reduction of primordial follicles, irregular menstrual cycle, premature absence of corpus luteum, as well as reduced fertility, resembling premature ovarian insufficiency syndrome in humans that is linked to premature menopause. This could especially affect the Western parts of the world, where the age for childbirth is continuously being increased and acetaminophen is recommended during pregnancy for pain and fever. We therefore highlight an urgent need for more studies to verify these data including both experimental and epidemiological approaches.

Assessing the impact of in-utero exposures: potential effects of paracetamol on male reproductive development

Human male reproductive disorders (cryptorchidism, hypospadias, testicular cancer and low sperm counts) are common and some may be increasing in incidence worldwide. These associated disorders can arise from subnormal testosterone production during fetal life. This has resulted in a focus on in-utero environmental influences that may result in reproductive effects on the offspring in later life. Over recent years, there has been a dramatic increase in the scientific literature describing associations between in-utero environmental exposures (eg, industrial chemicals and pharmaceuticals) and subsequent reproductive outcomes in male offspring. This includes studies investigating a potential role for in-utero analgesic exposure(s) on the fetal testis; however, providing definitive evidence of such effects presents numerous challenges. In this review, we describe an approach to assessing the potential clinical relevance of in-utero (and postnatal) environmental exposures on subsequent male reproductive function using exposure to the analgesic paracetamol as an example.

Male urinary paracetamol and semen quality

The endocrine-disrupting properties of paracetamol have been previously demonstrated in rodent studies of abnormal sperm morphology and diminished testosterone production, in addition to epidemiologic studies of diminished couple fecundity. In this study, we examined the relationship between paracetamol and its metabolite p-aminophenol quantified in a single spot urine and semen quality among 501 male partners of couples planning for pregnancy. Men provided a urine specimen and two fresh semen samples collected approximately one month apart and underwent 24-h analysis for 35 semen quality parameters. Paracetamol and p-aminophenol were quantified in urine by ultra-high-performance liquid chromatography coupled with an electrospray triple quadrupole mass spectrometry. The relationship between natural-log-transformed urinary paracetamol and p-aminophenol rescaled by their standard deviation and 21 Box-Cox-transformed, 14 non-transformed semen parameters was assessed using linear mixed-effects models. The median concentrations (IQR) of urinary paracetamol and p-aminophenol were 15.5 ng/mL (5.44, 73.5) and 978 ng/mL (500, 1596), respectively. Following adjustment for creatinine and age, a 1-standard deviation increase in log-transformed urinary paracetamol was associated with a reduction in beat cross-frequency and an increase in DNA fragmentation [β (95% CI): -0.59 Hz (-1.16, -0.03) and 0.05% (0.01, 0.09), respectively]. These findings were corroborated in models of categorical chemical concentrations; higher concentrations of paracetamol remained associated with reduced beat cross-frequency and increased DNA fragmentation. A 1-standard deviation increase in log-transformed urinary p-aminophenol was associated with a reduction in sperm head area [β (95% CI): -0.1 μm2 (-0.18, -0.02) and width -0.02 μm (-0.04, -0.01)]. However, only the association with sperm head area remained statistically significant in models of p-aminophenol quartiles. Our findings suggest that adult male urinary paracetamol is associated with sperm motility and DNA fragmentation, while the metabolite, p-aminophenol, is predominantly associated with sperm head morphometry.

Hemoglobin Adducts and Urinary Metabolites of Arylamines and Nitroarenes

Arylamines and nitroarenes are intermediates in the production of pharmaceuticals, dyes, pesticides, and plastics and are important environmental and occupational pollutants. N-Hydroxyarylamines are the toxic common intermediates of arylamines and nitroarenes. N-Hydroxyarylamines and their derivatives can form adducts with hemoglobin (Hb-adducts), albumin, DNA, and tissue proteins in a dose-dependent manner. Most of the arylamine Hb-adducts are labile and undergo hydrolysis in vitro, by mild acid or base, to form the arylamines. According to current knowledge of arylamine adduct-formation, the hydrolyzable fraction is derived from the reaction products of the arylnitroso derivatives that yield arylsulfinamide adducts with cysteine. Hb-adducts are markers for the bioavailability of N-hydroxyarylamines. Hb-adducts of arylamines and nitroarenes have been used for many biomonitoring studies for over 30 years. Hb-adducts reflect the exposure history of the last four months. Biomonitoring of urinary metabolites is a less invasive process than biomonitoring blood protein adducts, and urinary metabolites have served as short-lived biomarkers of exposure to these hazardous chemicals. However, in case of intermittent exposure, urinary metabolites may not be detected, and subjects may be misclassified as nonexposed. Arylamines and nitroarenes and/or their metabolites have been measured in urine, especially to monitor the exposure of workers. This review summarizes the results of human biomonitoring studies involving urinary metabolites and Hb-adducts of arylamines and nitroarenes. In addition, studies about the relationship between Hb-adducts and diseases are summarized.

Prenatal exposure to paracetamol/acetaminophen and precursor aniline impairs masculinisation of male brain and behaviour

Paracetamol/acetaminophen (N-Acetyl-p-Aminophenol; APAP) is the preferred analgesic for pain relief and fever during pregnancy. It has therefore caused concern that several studies have reported that prenatal exposure to APAP results in developmental alterations in both the reproductive tract and the brain. Genitals and nervous system of male mammals are actively masculinised during foetal development and early postnatal life by the combined actions of prostaglandins and androgens, resulting in the male-typical reproductive behaviour seen in adulthood. Both androgens and prostaglandins are known to be inhibited by APAP. Through intrauterine exposure experiments in C57BL/6 mice, we found that exposure to APAP decreased neuronal number in the sexually dimorphic nucleus (SDN) of the preoptic area (POA) in the anterior hypothalamus of male adult offspring. Likewise, exposure to the environmental pollutant and precursor of APAP, aniline, resulted in a similar reduction. Decrease in neuronal number in the SDN-POA is associated with reductions in male sexual behaviour. Consistent with the changes, male mice exposed in uteri to APAP exhibited changes in urinary marking behaviour as adults and had a less aggressive territorial display towards intruders of the same gender. Additionally, exposed males had reduced intromissions and ejaculations during mating with females in oestrus. Together, these data suggest that prenatal exposure to APAP may impair male sexual behaviour in adulthood by disrupting the sexual neurobehavioral programming. These findings add to the growing body of evidence suggesting the need to limit the widespread exposure and use of APAP by pregnant women.

Urinary paracetamol and time-to-pregnancy

STUDY QUESTION

Is preconception urinary paracetamol (acetaminophen) associated with time-to-pregnancy (TTP)?

SUMMARY ANSWER

Higher urinary paracetamol concentrations among male partners were associated with a longer TTP.

WHAT IS KNOWN ALREADY

Paracetamol is a commonly used analgesic among women and men of all ages. As metabolites of select chemicals used in the manufacturing of polyurethane foam, dyes and various industrial products, as well as a common medicinal product, paracetamol and its primary metabolite p-aminophenol, are ubiquitous in the environment. Studies investigating the relationship between adult urinary concentrations of paracetamol and TTP are lacking.

STUDY DESIGN, SIZE, DURATION

This prospective cohort included 501 couples discontinuing contraception for the purposes of attempting conception during the years 2005-2009 and residing in Michigan or Texas, USA.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Total urinary paracetamol, its metabolite para-aminophenol (p-aminophenol), and a summary measure of both urinary biomarkers were quantified by ultra-performance liquid chromatography coupled with an electrospray triple quadrupole mass spectrometry (UPLC-ESI-MS/MS). Female partners used the Clearblue® digital home test to confirm pregnancy. Cox's proportional odds models for discrete survival time were used to estimate fecundability odds ratios (FORs) and 95% confidence intervals (CIs), adjusting for age, body mass index (BMI), urinary creatinine, preconception smoking status, race/ethnicity and household income. Models were further adjusted for hypothyroidism and hypertension as an attempt to account for possible indications of paracetamol medication use. FOR estimates <1.0 denote a longer TTP (diminished fecundity). Models were performed to examine urinary concentrations of paracetamol as a continuous and variable or categorized into quartiles. In light of TTP being a couple-dependent outcome, models were first performed for females and males, modeled separately, and then modeled for couples with each partner's concentrations being adjusted for the other.

MAIN RESULTS AND THE ROLE OF CHANCE

Among the 501 enrolled couples, 347 (69%) had an human chorionic gonadotrophin confirmed pregnancy. Urinary concentrations of paracetamol were lowest among females and males who achieved pregnancy and p-aminophenol concentrations were lowest among those not achieving pregnancy. Urinary paracetamol concentrations were higher among female than male partners (Median = 26.6 and 13.2 ng/ml, respectively; P < 0.0001). After adjustment for age, BMI, urinary creatinine, preconception smoking status, race/ethnicity and household income, the highest quartile of male urinary paracetamol was associated with a longer TTP [FOR = 0.67; 95% CI = (0.47, 0.95)]. This association remained after adjustment for chronic health conditions, hypothyroidism and hypertension and female partner's urinary paracetamol concentration [FOR = 0.65; 95% CI = (0.45, 0.94)]. No associations were observed between female or male partners' urinary concentrations of paracetamol or of its metabolite p-aminophenol when urinary concentrations were modeled continuously.

LIMITATIONS, REASONS FOR CAUTION

Only a single spot urine was available for analysis despite the short-lived nature of paracetamol. Additionally, participants were not asked to provide information on indication of use for paracetamol medications; any underlying conditions for the paracetamol use would have been potential confounders.

WIDER IMPLICATIONS OF THE FINDINGS

If corroborated with more robust studies, findings from our exploratory analysis may have both clinical and public health relevance among reproductive aged individuals, including those trying for pregnancy, given the prevalent use of paracetamol/acetaminophen medications and the ubiquitous nature of paracetamol in the environment.

STUDY FUNDING/COMPETING INTERESTS

This research was supported by the National Institutes of Health, Intramural Research Program, and Eunice Kennedy Shriver National Institute of Child Health and Human Development (contracts N01-HD-3-3355; N01-HD-3-3356; NOH-HD-3-3358; HHSN27500001/HHSN27500001). None of the authors have any conflicts to declare.

Analgesic use - prevalence, biomonitoring and endocrine and reproductive effects

Paracetamol and NSAIDs, in particular acetylsalicylic acid (aspirin) and ibuprofen, are among the most used and environmentally released pharmaceutical drugs. The differences in international trends in the sale and consumption of mild analgesics reflect differences in marketing, governmental policies, habits, accessibility, disease patterns and the age distribution of each population. Biomonitoring indicates ubiquitous and high human exposure to paracetamol and to salicylic acid, which is the main metabolite of acetylsalicylic acid. Furthermore, evidence suggests that analgesics can have endocrine disruptive properties capable of altering animal and human reproductive function from fetal life to adulthood in both sexes. Medical and public awareness about these health concerns should be increased, particularly among pregnant women.