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Toxicology Apr 2022Diazinon is an organophosphate pesticide that has a history of wide use. Developmental exposures to organophosphates lead to neurobehavioral changes that emerge early in...
Diazinon is an organophosphate pesticide that has a history of wide use. Developmental exposures to organophosphates lead to neurobehavioral changes that emerge early in life and can persist into adulthood. However, preclinical studies have generally evaluated changes through young adulthood, whereas the persistence or progression of deficits into middle age remain poorly understood. The current study evaluated the effects of maternal diazinon exposure on behavior and neurochemistry in middle age, at 1 year postpartum, comparing the results to our previous studies of outcomes at adolescence and in young adulthood (4 months of age) (Hawkey 2020). Female rats received 0, 0.5 or 1.0 mg/kg/day of diazinon via osmotic minipump throughout gestation and into the postpartum period. The offspring were tested on a battery of locomotor, affective, and cognitive tests at young adulthood and during middle age. Some of the neurobehavioral consequences of developmental DZN seen during adolescence and young adulthood faded with continued aging, whereas other neurobehavioral effects emerged with aging. At middle age, the rats showed few locomotor effects, in contrast to the locomotor hyperactivity that had been observed in adolescence. Notably, though, DZN exposure during development impaired reference memory performance in middle-aged males, an effect that had not been seen in the younger animals. Likewise, middle-aged females exposed to DZN showed deficient attentional accuracy, an effect not seen in young adults. Across adulthood, the continued potential for behavioral defects was associated with altered dopaminergic function, characterized by enhanced dopamine utilization that was regionally-selective (striatum but not frontal/parietal cortex). This study shows that the neurobehavioral impairments from maternal low dose exposure to diazinon not only persist, but may continue to evolve as animals enter middle age.
Topics: Animals; Behavior, Animal; Diazinon; Female; Insecticides; Male; Organophosphates; Organophosphorus Compounds; Rats
PubMed: 35452779
DOI: 10.1016/j.tox.2022.153189 -
Bulletin of Environmental Contamination... Jan 2017Organophosphate esters (OPEs) are synthetic phosphoric acid derivatives used in a wide variety of applications including as flame retardants and plasticizers. Their... (Review)
Review
Organophosphate esters (OPEs) are synthetic phosphoric acid derivatives used in a wide variety of applications including as flame retardants and plasticizers. Their production and usage has increased in recent years, due to the phase-out of other flame retardant formulations (e.g., polybrominated diphenyl ethers). As such, there has been a recent push to understand the global distribution of OPEs and their behaviour in biota. Multiple studies have been published over the last few years pertaining to OPE concentrations in biotic and abiotic environmental compartments, as well as the metabolism of OPEs in biota. This paper aims to provide a brief review of the occurrence and levels of OPEs in the environment, as well as recent developments concerning the elucidation of OPE metabolism in biota.
Topics: Animals; Birds; Environmental Monitoring; Environmental Pollutants; Fishes; Flame Retardants; Halogenated Diphenyl Ethers; Organophosphates; Plasticizers
PubMed: 27510993
DOI: 10.1007/s00128-016-1898-0 -
Ecotoxicology and Environmental Safety Aug 2022Organophosphate flame retardants (OPFRs) are alternatives to brominated flame retardants (BFRs) and have recently gained wide acceptance in various materials. For the...
Organophosphate flame retardants (OPFRs) are alternatives to brominated flame retardants (BFRs) and have recently gained wide acceptance in various materials. For the treatment and prevention of diseases, it is also important to clarify the relationship between OPFRs and tumors, despite the fact that OPFRs are less toxic than BFRs. This research used the TCGA and CTD databases for transcriptome profiling and identifying OPFRs-related genes. GO and KEGG analyses suggested that OPFRs may be closely related to colorectal cancer (CRC), and genes correlated with OPFRs were significantly and differently expressed between tumor and normal group. Further, OPFRs-related genes were associated with a good prognosis in CRC patients. The deeper research demonstrated that one of the OPFRs-triphenyl phosphate could significantly increased the viability and proliferation of CRC cell lines compared with the control group. In addition, Our research also found that melatonin at 50 μM could significantly impact CRC cell proliferation and migration ability induced by TPP.
Topics: Cell Line; Colorectal Neoplasms; Flame Retardants; Humans; Organophosphates; Organophosphorus Compounds
PubMed: 36068737
DOI: 10.1016/j.ecoenv.2022.113778 -
Langmuir : the ACS Journal of Surfaces... Feb 2017Understanding the molecular interactions between small molecules and double-stranded DNA has important implications on the design and development of DNA and DNA-protein...
Understanding the molecular interactions between small molecules and double-stranded DNA has important implications on the design and development of DNA and DNA-protein nanomaterials. Such materials can be assembled into a vast array of 1-, 2-, and 3D structures that contain a range of chemical and physical features where small molecules can bind via intercalation, groove binding, and electrostatics. In this work, we use a series of simulation-guided binding assays and spectroscopy techniques to investigate the binding of selected organophosphtates, methyl parathion, paraoxon, their common enzyme hydrolysis product p-nitrophenol, and double-stranded DNA fragments and DNA DX tiles, a basic building block of DNA-based materials. Docking simulations suggested that the binding strength of each compound was DNA sequence-dependent, with dissociation constants in the micromolar range. Microscale thermophoresis and fluorescence binding assays confirmed sequence-dependent binding and that paraoxon bound to DNA with K's between ∼10 and 300 μM, while methyl parathion bound with K's between ∼10 and 100 μM. p-Nitrophenol also bound to DNA but with affinities up to 650 μM. Changes in biding affinity were due to changes in binding mode as revealed by circular dichroism spectroscopy. Based on these results, two DNA DX tiles were constructed and analyzed, revealing tighter binding to the studied compounds. Taken together, the results presented here add to our fundamental understanding of the molecular interactions of these compounds with biological materials and opens new possibilities in DNA-based sensors, DNA-based matrices for organophosphate extraction, and enzyme-DNA technologies for organophosphate hydrolysis.
Topics: Circular Dichroism; DNA; Nanostructures; Organophosphates; Paraoxon
PubMed: 28165751
DOI: 10.1021/acs.langmuir.6b03131 -
Environmental Science & Technology May 2020Tris(2-chloroethyl) phosphate (TCEP), a typical chlorinated organophosphate ester (OPE), is an emerging contaminant of global concern because of its frequent occurrence,...
Tris(2-chloroethyl) phosphate (TCEP), a typical chlorinated organophosphate ester (OPE), is an emerging contaminant of global concern because of its frequent occurrence, potential toxic effects, and persistence in the environment. In this study, we investigated the microbial TCEP biotransformation and the development of microbial communities in sediment microcosms with repeated TCEP amendments. The TCEP degradation fitted pseudo-zero-order kinetics, with reaction rates of 0.068 mg/(L h) after the first spike of 5 mg/L and 1.85 mg/(L h) after the second spike of 50 mg/L. TCEP was mainly degraded via phosphoester bond hydrolysis, evidenced by the production of bis(2-chloroethyl) phosphate (BCEP) and mono-chloroethyl phosphate (MCEP). Bis(2-chloroethyl) 2-hydroxyethyl phosphate (TCEP-OH), phosphoric bis(2-chloroethyl) (2-oxoethyl) ester (TCEP-CHO), phosphoric acid bis(2-chloroethyl)(carboxymethyl) ester (TCEP-COOH), and 2-chloroethyl 2-hydroxyethyl hydrogen phosphate (BCEP-OH) were also identified as microbial TCEP transformation products, indicating that TCEP degradation may follow hydrolytic dechlorination and oxidation pathways. Microbial community compositions in TCEP-amended microcosms shifted away from control microcosms after the second TCEP spike. Burkholderiales and Rhizobiales were two prevalent bacterial guilds enriched in TCEP-amended microcosms and were linked to the higher abundances of alkaline and acid phosphatase genes and genes involved in the metabolism of 2-chloroethanol, a side product of TCEP hydrolysis, indicating their importance in degrading TCEP and its metabolites.
Topics: Biotransformation; Flame Retardants; Microbiota; Organophosphates; Phosphates; Phosphines
PubMed: 32264671
DOI: 10.1021/acs.est.9b07042 -
Nature Chemical Biology Oct 2009
Topics: Binding Sites; Catalysis; DNA; Hydrolysis; Organophosphates; Thermodynamics
PubMed: 19763101
DOI: 10.1038/nchembio.224 -
Casopis Lekaru Ceskych Sep 1993The author summarizes contemporary knowledge on the action of organophosphates with emphasis on non-cholinergic mechanisms. Intoxication with these substances is... (Review)
Review
The author summarizes contemporary knowledge on the action of organophosphates with emphasis on non-cholinergic mechanisms. Intoxication with these substances is characterized by four basic processes: absorption, transport, metabolism and the toxic effect proper. The latter involves cholinesterase inhibition at the cholinergic synapses with subsequent accumulation of acetylcholine. However, non-cholinergic processes are also involved such as the effect on levels of cyclic nucleotides, the peptidergic system, receptors, liver metabolism and the stressogenic action. From the review ensues that knowledge of non-cholinergic, mechanisms of action could reveal new approaches to treatment of intoxications with these substances.
Topics: Animals; Humans; Organophosphate Poisoning; Organophosphates
PubMed: 8402819
DOI: No ID Found -
Ecotoxicology and Environmental Safety Mar 2020Since many household products used by individuals contain flame retardants (FRs), there is more chance that these chemicals may be present in the various exhibit of the...
Since many household products used by individuals contain flame retardants (FRs), there is more chance that these chemicals may be present in the various exhibit of the indoor environment. Despite being one of the fastest-growing economies worldwide, the contamination level, sources, products, and pathways of FRs in India, is either not known or limited. This inspired us to investigate the level, profile, spatial distribution, and sources of different classes of FRs in the indoor air. For this purpose, 15 brominated, 2 chlorinated, and 8 organophosphate FRs (OPFRs) were investigated in indoor air samples from urban and suburban sites of an Indian state of Bihar. Additionally, inhalation health risk exposure to children and the adult was estimated to predict the risk of these chemicals. Overall, ∑OPFRs (median 351 pg/m) was the most prominent in air, followed by novel brominated FR (∑NBFRs) (median 278 pg/m), polybrominated diphenyl ether (∑PBDE) (median 5.05 pg/m), and dechlorane plus (∑DPs) (median 2.52 pg/m), and accounted for 55%, 44%, 0.8% and 0.4% of ∑FRs, respectively. Generally, ∑PBDEs (median 6.29 pg/m) and ∑OPFRs (median 355 pg/m) were measured high at sub-urban sites, while urban sites had the highest level of ∑DPs (median 2.81 pg/m) and ∑NBFRs (median 740 pg/m). BDE-209 was most abundant among ∑PBDEs, while syn-DP dominated in ∑DPs. Likewise, DBDPE was most prevalent in ∑NBFRs, while TMPP topped among ∑OPFRs. The principal component analysis revealed contribution from household items, food packaging and paints, hydraulic fluid, a gasoline additive, and de-bromination of BDE-209 as the primary sources of FRs. The estimated daily inhalation exposure (DIE) indicated a relatively high risk to children than the adult. The DIE of individual FR was several folds lower than their corresponding oral reference dose (RfDs), suggesting minimal risk. However, exposure risk, especially to children, may still need attention because other routes of intake may always be significant in the case of Bihar.
Topics: Air Pollutants; Air Pollution, Indoor; Flame Retardants; Humans; Hydrocarbons, Halogenated; India; Inhalation Exposure; Organophosphates; Principal Component Analysis; Risk Assessment
PubMed: 32006868
DOI: 10.1016/j.ecoenv.2020.110212 -
Bulletin of Environmental Contamination... Dec 1981
Comparative Study
Topics: Animals; Fishes; Flame Retardants; Goldfish; Killifishes; Organophosphates; Organophosphorus Compounds; Species Specificity
PubMed: 7337849
DOI: 10.1007/BF01611095 -
Reviews on Environmental Health 2015Organophosphate (OP) compounds are the most widely used pesticides with more than 100 OP compounds in use around the world. The high-intensity use of OP pesticides... (Review)
Review
Organophosphate (OP) compounds are the most widely used pesticides with more than 100 OP compounds in use around the world. The high-intensity use of OP pesticides contributes to morbidity and mortality in farmworkers and their families through acute or chronic pesticides-related illnesses. Many factors contributing to adverse health effects have been investigated by researchers to determine pathways of OP-pesticide exposure among farmers in developed and developing countries. Factors like wind/agricultural pesticide drift, mixing and spraying pesticides, use of personal protective equipment (PPE), knowledge, perceptions, washing hands, taking a shower, wearing contaminated clothes, eating, drinking, smoking, and hot weather are common in both groups of countries. Factors including low socioeconomic status areas, workplace conditions, duration of exposure, pesticide safety training, frequency of applying pesticides, spraying against the wind, and reuse of pesticide containers for storage are specific contributors in developing countries, whereas housing conditions, social contextual factors, and mechanical equipment were specific pathways in developed countries. This paper compares existing research in environmental and behavioural exposure modifying factors and biological monitoring between developing and developed countries. The main objective of this review is to explore the current depth of understanding of exposure pathways and factors increasing the risk of exposure potentially leading to adverse health effects specific to each group of countries.
Topics: Agriculture; Environmental Monitoring; Humans; Occupational Exposure; Organophosphates; Pesticides; Workforce
PubMed: 25741936
DOI: 10.1515/reveh-2014-0072