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Frontiers in Behavioral Neuroscience 2019Impulsive and compulsive traits represent a variety of maladaptive behaviors defined by the difficulties to stop an improper response and the control of a repeated...
Impulsive and compulsive traits represent a variety of maladaptive behaviors defined by the difficulties to stop an improper response and the control of a repeated behavioral pattern without sensitivity to changing contingencies, respectively. Otherwise, human beings are continuously exposed to plenty neurotoxicological agents which have been systematically linked to attentional, learning, and memory dysfunctions, both preclinical and clinical studies. Interestingly, the link between both impulsive and compulsive behaviors and the exposure to the most important xenobiotic compounds have been extensively developed; although the information has been rarely summarized. For this, the present systematic review schedule and analyze in depth the most important works relating different subtypes of the above-mentioned behaviors with 4 of the most important xenobiotic compounds: Lead (Pb), Methylmercury (MeHg), Polychlorinated biphenyls (PCB), and Organophosphates (OP) in both preclinical and clinical models. Systematic search strategy on PubMed databases was developed, and the most important information was structured both in text and in separate tables based on rigorous methodological quality assessment. For Lead, Methylmercury, Polychlorinated biphenyls and organophosphates, a total of 44 (31 preclinical), 34 (21), 38 (23), and 30 (17) studies were accepted for systematic synthesis, respectively. All the compounds showed an important empirical support on their role in the modulation of impulsive and, in lesser degree, compulsive traits, stronger and more solid in animal models with inconclusive results in humans in some cases (i.e., MeHg). However, preclinical and clinical studies have systematically focused on different subtypes of the above-mentioned behaviors, as well as impulsive choice or habit conformations have been rarely studied. The strong empirical support in preclinical studies contrasts with the lack of connection between preclinical and clinical models, as well as the different methodologies used. Further research should be focused on dissipate these differences as well as deeply study impulsive choice, decision making, risk taking, and cognitive flexibility, both in experimental animals and humans.
PubMed: 31333425
DOI: 10.3389/fnbeh.2019.00139 -
Ecotoxicology and Environmental Safety Sep 2022Organophosphate flame retardants (OPFRs) are increasingly and widely used as substitutes for brominated flame retardants in daily life. The chemical structure of OPFRs... (Review)
Review
Organophosphate flame retardants (OPFRs) are increasingly and widely used as substitutes for brominated flame retardants in daily life. The chemical structure of OPFRs is very similar to that of organophosphorus pesticides, leading to concerns about their neurotoxicity. A few epidemiological studies have been published with inconsistent results on this topic, and a systematic scoping review is needed to provide an overview or map of the current evidence on the relationship of OPFRs with neurodevelopmental toxicity. Therefore, MEDLINE (accessed through PubMed), Web of Science, and CNKI (Chinese National Knowledge Infrastructure) were systematically searched for articles published in the last two decades. Nine eligible articles were included in the present systematic scoping review for adherence to the predefined PECOS (population, exposure, comparison, outcome, study design) statement. Six studies were conducted in the USA, and the remaining three studies were conducted in Austria, Norway and China. A total of 2 581 children (1 203 females and 1 378 males) were included. Half of the included studies focused on the adverse effects of OPFR exposure on cognition in children, while others primarily focused on the behaviors of children. In summary, the current evidence suggests inverse associations between early-life exposure to OPFRs and the childhood intelligence quotient and internalizing behavior and positive relationships of OPFR exposure with externalizing behavior. However, some differences in the timing of sample collection for exposure measurements, in the individual OPFR metabolites available, in the neurodevelopmental scales for outcome measurement, and in the statistical methods used to analyze the data are noted. In addition, further studies are warranted to evaluate some important issues, such as sex differences in the association, exposure-sensitive periods, and cumulative exposure risk assessment.
Topics: Child; Epidemiologic Studies; Female; Flame Retardants; Humans; Male; Organophosphates; Organophosphorus Compounds; Pesticides
PubMed: 35988382
DOI: 10.1016/j.ecoenv.2022.113973 -
Environmental Research Aug 2020A growing body of evidences suggests an association between early exposure to organophosphates (OPs), organochlorines (OCs), pyrethroids or carbamates and autism...
Pesticides used in Europe and autism spectrum disorder risk: can novel exposure hypotheses be formulated beyond organophosphates, organochlorines, pyrethroids and carbamates? - A systematic review.
BACKGROUND
A growing body of evidences suggests an association between early exposure to organophosphates (OPs), organochlorines (OCs), pyrethroids or carbamates and autism spectrum disorder (ASD). However, there are limited data about the other pesticide groups, especially in Europe.
OBJECTIVES
Based on a systematic review, we aimed to assess the influence of neuro- and thyrotoxic agricultural and domestic pesticides (other than OPs, OCs, pyrethroids and carbamates) authorized in Europe on risk of ASD in children or ASD behavioral phenotypes in rodents.
METHODS
Pesticides were initially identified in the Hazardous Substances Data Bank. 20 currently used (10 pesticide groups) were retained based on the higher exposure potential. Epidemiological (children) and in vivo (rodents) studies were identified through PubMed, Web of Science and TOXLINE, without restriction of publication date or country (last update: November 2019). The risk of bias and level of evidence were also assessed. This systematic review is registered at the International Prospective Register of Systematic Reviews (PROSPERO, registration number CRD42019145384).
RESULTS
In total, two epidemiological and 15 in vivo studies were retained, focusing on the azole, neonicotinoid, phenylpyrazole and phosphonoglycine pesticide groups. No study was conducted in Europe. Glyphosate, imidacloprid, clothianidin, myclobutanil, acetamiprid, tebuconazole, thiabendazole and fipronil, globally reported an association with an increased risk of ASD in children and/or ASD behavioral phenotypes in rodents. In children, glyphosate and myclobutanil showed a "moderate level of evidence" in their association with ASD, whereas imidacloprid showed an "inadequate level of evidence". In rodents, clothianidin, imidacloprid and glyphosate showed a "high level of evidence" in their association with altered behavioral, learning and memory skills.
CONCLUSION
In the framework of environmental risk factors of ASD, novel hypotheses can be formulated about early exposure to eight pesticides. Glyphosate presented the most salient level of evidence. Given their neuro- and thyrotoxic properties, additional studies are needed for the 12 other pesticides not yet studied as potential ASD risk factors according to our inclusion criteria.
Topics: Autism Spectrum Disorder; Carbamates; Child; Europe; Humans; Organophosphates; Pesticides; Pyrethrins
PubMed: 32460093
DOI: 10.1016/j.envres.2020.109646 -
Journal of Infection and Public Health Jul 2024The objective of this were conducted to elucidate spatiotemporal variations in malaria epidemiology in Gabon since 1980. For that, five databases, were used to collect... (Meta-Analysis)
Meta-Analysis Review
The objective of this were conducted to elucidate spatiotemporal variations in malaria epidemiology in Gabon since 1980. For that, five databases, were used to collect and identify all studies published between 1980 and 2023 on malaria prevalence, antimalarial drug resistance, markers of antimalarial drug resistance and insecticide resistance marker. The findings suggest that Gabon continues to face malaria as an urgent public health problem, with persistently high prevalence rates. Markers of resistance to CQ persist despite its withdrawal, and markers of resistance to SP have emerged with a high frequency, reaching 100 %, while ACTs remain effective. Also, recent studies have identified markers of resistance to the insecticides Kdr-w and Kdr-e at frequencies ranging from 25 % to 100 %. Ace1R mutation was reported with a frequency of 0.4 %. In conclusion, the efficacy of ACTs remains above the threshold recommended by the WHO. Organo-phosphates and carbamates could provide an alternative for vector control.
Topics: Gabon; Humans; Malaria; Prevalence; Antimalarials; Insecticide Resistance; Drug Resistance; Animals; Insecticides
PubMed: 38870682
DOI: 10.1016/j.jiph.2024.05.047 -
Journal of Toxicology and Environmental... May 2022Studies of nervous system effects of glyphosate, a widely used herbicide, have not been critically examined. The aim of this paper was to systematically review...
Studies of nervous system effects of glyphosate, a widely used herbicide, have not been critically examined. The aim of this paper was to systematically review glyphosate-induced neurotoxicity literature to determine its usefulness in regulatory decision-making. The review was restricted to mammalian studies of behavior, neuropathology, and neuropharmacology; and other biochemical studies were considered supplementary information. Glyphosate formulation studies were also considered, despite uncertainties regarding toxicities of the formulated products; no studies used a formulation vehicle as the control. Inclusion criteria were developed to ensure consistent evaluation of studies, and investigations were also ranked using ToxRTool software to determine reliability. There were 27 studies (open literature and available regulatory reports), but 11 studies were considered unreliable (mostly due to critical methodological deficiencies). There were only seven acceptable investigations on glyphosate alone. Studies differed in terms of dosing scenarios, experimental designs, test species, and commercial product. Limitations included using only one dose and/or one test time, small sample sizes, limited data presentation, and/or overtly toxic doses. While motor activity was the most consistently affected endpoint (10 of 12 studies), there were considerable differences in outcomes. In six investigations, there were no marked neuropathological changes in the central or peripheral nervous system. Other neurological effects were less consistent, and some outcomes were less convincing due to influences including high variability and small effect sizes. Taken together, these studies do not demonstrate a consistent impact of glyphosate on the structure or function of the mammalian nervous system.
Topics: Animals; Glycine; Herbicides; Mammals; Reproducibility of Results; Glyphosate
PubMed: 35676826
DOI: 10.1080/10937404.2022.2083739 -
Environmental Pollution (Barking, Essex... Apr 2024Chronic respiratory diseases are a dealing cause of death and disability worldwide. Their prevalence is steadily increasing and the exposure to environmental... (Meta-Analysis)
Meta-Analysis Review
Chronic respiratory diseases are a dealing cause of death and disability worldwide. Their prevalence is steadily increasing and the exposure to environmental contaminants, including Flame Retardants (FRs), is being considered as a possible risk factor. Despite the widespread and continuous exposure to FRs, the role of these contaminants in chronic respiratory diseases is yet not clear. This study aims to systematically review the association between the exposure to FRs and chronic respiratory diseases. Searches were performed using the Cochrane Library, MEDLINE, EMBASE, PUBMED, SCOPUS, ISI Web of Science (Science and Social Science Index), WHO Global Health Library and CINAHL EBSCO. Among the initial 353 articles found, only 9 fulfilled the inclusion criteria and were included. No statistically significant increase in the risk for chronic respiratory diseases with exposure to FRs was found and therefore there is not enough evidence to support that FRs pose a significantly higher risk for the development or worsening of respiratory diseases. However, a non-significant trend for potential hazard was found for asthma and rhinitis/rhinoconjunctivitis, particularly considering urinary organophosphate esters (OPEs) including TNBP, TPHP, TCEP and TCIPP congeners/compounds. Most studies showed a predominance of moderate risk of bias, therefore the global strength of the evidence is low. The limitations of the studies here reviewed, and the potential hazardous effects herein identified highlights the need for good quality large-scale cohort studies in which biomarkers of exposure should be quantified in biological samples.
Topics: Humans; Flame Retardants; Organophosphorus Compounds; Organophosphates; Asthma; Environmental Monitoring; Dust; Halogenated Diphenyl Ethers
PubMed: 38458527
DOI: 10.1016/j.envpol.2024.123733 -
Journal of Medicine and Life Jan 2023Measurements of blood cholinesterase (ChE) activities, including those of erythrocytes (EChE), plasma or serum (PChE), and whole blood (WBChE), are used to assess... (Meta-Analysis)
Meta-Analysis
Measurements of blood cholinesterase (ChE) activities, including those of erythrocytes (EChE), plasma or serum (PChE), and whole blood (WBChE), are used to assess exposure to ChE-inhibiting pesticides. The purpose of this review was to report normal reference ChE activities in the blood of healthy adult humans, as determined by a modified electrometric method. We performed a systematic review following PRISMA guidelines. Single-group meta-analysis of means of PChE, EChE, and WBChE activities of adult healthy subjects was conducted using the random effects model. The programs used were Open-Meta Analyst and Meta-Essentials Version 1.5. Studies selected for analysis comprised 21, 19, and 4 reports of normal reference/baseline PChE, EChE, and WBChE activities in 690, 635, and 121 healthy adult males and/or females, respectively. The meta-analysis showed normal reference values of the means (effect sizes) with 95% CI of PChE, EChE, and WBChE activities of healthy adult subjects, which were 1.078 (1.015, 1.142), 1.075 (1.024, 1.125) and 1.331 (1.226, 1.436), respectively. By the subgroup analysis, heterogeneity (I2>89%) was considerably reduced in females to 4.4% and 30.1% for PChE and EChE, respectively. Funnel plots indicated no publication bias. However, Egger's regression confirmed the symmetry of the data points for PChE and WBChE activities with a significant effect on EChE. This meta-analysis showed normal reference values of PChE, EChE, and WBChE activities, measured by a modified electrometric method, in healthy adult humans.
Topics: Adult; Female; Humans; Male; Cholinesterases; Publication Bias
PubMed: 36873131
DOI: 10.25122/jml-2022-0215 -
Systematic Reviews May 2020Environmental factors such as pollution, pesticide exposure and socio-demographic location have been implicated as a pressure capable of altering genetic make-up....
Environmental factors such as pollution, pesticide exposure and socio-demographic location have been implicated as a pressure capable of altering genetic make-up. Altered genetic sequence of genes encoding enzymes may result in single nucleotide polymorphism (SNP). Of peculiar interest is the genetic variance on the paraoxonase-1 gene induced by pre- and postnatal exposure to pesticides. SNP have been reported on the paraoxonase-1 gene and post-xenobiotic exposure and are presumed to alter gene sequence and ultimately enzymatic activity. The altered enzymatic activity may facilitate neurodevelopment disorders. Autism spectrum disorders (ASD) and attention deficit hyperactivity disorder (ADHD) are among the neurodevelopment disorders of which prevalence is concurrently associated with increasing environmental xenobiotic exposure. The variance on xenobiotic metabolising genes is associated with altered neurodevelopment outcome and ultimately altered neurobehavioural outcome. Prime interests of this systematic review were to establish an understanding of the sequences on the paraoxonase-1 gene associated with adverse neurobehavioural outcome. An in-depth literature search was conducted using the term combination "pesticide exposure, pre- and postnatal exposure, organophosphates/organophosphorus, single nucleotide polymorphism, paraoxonase-1 (PON-1), neurodevelopment/neurobehavioural outcome in child/infant". Articles published from the year 2000 to 2018 were considered for review. The result showed that variance on the PON1-108 and 192 alleles could be implicated in the development of altered neurobehavioural outcomes.
Topics: Aryldialkylphosphatase; Child; Environmental Exposure; Humans; Organophosphates; Pesticides; Polymorphism, Single Nucleotide
PubMed: 32386510
DOI: 10.1186/s13643-020-01330-9 -
Environmental Science. Processes &... Feb 2024This work presents a case study in applying a systematic review framework (SYRINA) to the identification of chemicals as endocrine disruptors. The suitability and...
This work presents a case study in applying a systematic review framework (SYRINA) to the identification of chemicals as endocrine disruptors. The suitability and performance of the framework is tested with regard to the widely accepted World Health Organization definition of an endocrine disruptor (ED). The endocrine disrupting potential of triphenyl phosphate (TPP), a well-studied flame retardant reported to exhibit various endocrine related effects was assessed. We followed the 7 steps of the SYRINA framework, articulating the research objective Populations, Exposures, Comparators, Outcomes (PECO) statements, performed literature search and screening, conducted study evaluation, performed data extraction and summarized and integrated the evidence. Overall, 66 studies, consisting of , and epidemiological data, were included. We concluded that triphenyl phosphate could be identified as an ED based on metabolic disruption and reproductive function. We found that the tools used in this case study and the optimizations performed on the framework were suitable to assess properties of EDs. A number of challenges and areas for methodological development in systematic appraisal of evidence relating to endocrine disrupting potential were identified; significant time and effort were needed for the analysis of mechanistic data in this case study, thus increasing the workload and time needed to perform the systematic review process. Further research and development of this framework with regards to grey literature (non-peer-reviewed literature) search, harmonization of study evaluation methods, more consistent evidence integration approaches and a pre-defined method to assess links between adverse effect and endocrine activity are recommended. It would also be advantageous to conduct more case studies for a chemical with less data than TPP.
Topics: Organophosphates; Endocrine Disruptors
PubMed: 38205707
DOI: 10.1039/d3em00353a -
Frontiers in Human Neuroscience 2021In recent years, pyrethroids have emerged as a less toxic alternative to eliminate insect pests. However, some animal studies and studies with children show that these...
In recent years, pyrethroids have emerged as a less toxic alternative to eliminate insect pests. However, some animal studies and studies with children show that these pesticides are toxic and lead to neurobehavioral effects similar to other pesticides, such as organophosphates. The purpose of this review was to systematize the epidemiological scientific evidence about the neurobehavioral, neuromotor, and neurocognitive effects in agricultural workers and their children exposed to pyrethroid pesticides. We conducted two searches (with different terms) in PubMed and Scopus databases, including articles in Spanish and English language on the effects of occupational exposure to pyrethroid pesticides associated with neurobehavioral, neuromotor, and neurocognitive functioning of agricultural workers and their children. There were no filters by year, and the search included studies till march 2021. To develop the search, we followed the recommendations contained in the PRISMA guidelines and the PICO strategy. The results show that in 66.6% of the studies reviewed (8 of 12 studies), agricultural workers or their children occupationally exposed to pyrethroid pesticides have a higher risk of presenting difficulties in their neurocognitive, neuromotor, or neurobehavioral performance, mainly associated with attention, processing speed (linked to hand-eye coordination), and motor coordination. There are still few studies that address this issue. However, the quality of most of the research conducted (83% intermediate or high quality) confirms the risk for neurobehavioral health in agricultural workers due to occupational exposure to pyrethroids. More research is required evaluating the exposure to pyrethroids, including biomarkers and validated neurobehavioral and neuromotor tests, in addition to evaluating the effect of simultaneous exposure to other hazardous pesticides. Assuming that the use of pyrethroids is increasing considerably and faster than the scientific evidence, it is suggested as a precautionary principle to regulate, more strictly, the sale of pyrethroids and other pesticides.
PubMed: 34335205
DOI: 10.3389/fnhum.2021.648171