Tricresyl Phosphate Research Articles

In vivo screening evaluation of 12 chemicals as candidate endocrine disruptors using ovariectomized mouse uterotrophic bioassay.

Semi flexible polyurethane (PU) foam provides various applications in aerospace as well as daily life due to its vibration dampening, sound absorption, thermal insulation properties etc. One of the major disadvantages of PU foams is its poor fire-resistant characteristics. The present study aimed to improve the fire retardant behavior of PU foam by incorporation of fillers like melamine powder (M.P) and tricresyl phosphate (TCP) in PU matrix. A set of PU foams were prepared with M.P alone, with TCP alone and with a combination of both melamine powder and TCP. The effect of these fire retardants on mechanical, thermal and fire retardant properties of semi flexible PU foam were evaluated based on density, resilience ball rebound, compressive strength, tensile strength, thermal stability, thermal conductivity, limiting oxygen index (LOI) and fire test. In addition, Cell morphology of PU foam was examined using scanning electron Microscope (SEM). LOI was improved from 19% to 26% with the addition of fire retardants. Cushioning property was retained however density was increased with the addition of fire retardants. 40% melamine powder and 40% TCP with respect to premix have been chosen as the optimized composition based on the fire resistant and physical properties. Scale up studies of the developed PU foam was done up to 1 m × 1 m size foam pad. With respect to the lab level properties, LOI value of 26% was retained and resilience ball rebound value change was found to be minimal.

Studying the lubrication of tricresyl phosphate (TCP) blends with base oils provides a better understanding of the reaction mechanism of TCP. However, given that some studies point out the weak role of base oils, this aspect is frequently overlooked in research. To explore the distinctions between pure TCP and TCP-base oil blended systems as well as to elucidate the underlying mechanism of the tribological properties, we employed reactive force field molecular dynamics (ReaxFF-MD) to investigate the tribochemical reactions and tribological properties of different ratios of TCP and octene molecules confined between iron and iron oxide substrates at different loads. Results indicate that the addition of octene molecules to TCP reduces friction and wear of the system, while the ameliorating effect of octene is influenced by surface materials and loads. On the Fe surface, octene inhibits the dissociation of CTCP-OTCP bonds, the formation of P-OTCP bonds, and the polymerization of TCP, resulting in a slowdown in interfacial shear and a reduction in the formation of bridge bonds. Consequently, the tribological properties are improved, particularly under high loads. In contrast, this enhancement is not pronounced on the Fe2O3 surface, where TCP primarily undergoes dissociation of P-OTCP bonds, with octene only affecting the polymerization of TCP. The steady-state friction coefficient of the unfailed models on the Fe surface is lower than that on the Fe2O3 surface due to the nucleophilic substitution with TCP, generating remarkable interfacial shear from polyphosphate clusters, whereas TCP forms stabilized adsorbed carbon films by carbon rings on the Fe surface. Additionally, the Fe substrate readily forms iron-carbon bonds, producing numerous bridge bonds that cause severe wear. On the contrary, the Fe2O3 substrate constructs fewer bridge bonds on account of unstable adsorption of carbon rings, presenting superior wear resistance.

Flame retardant tricresyl phosphate gestational exposure induced endocrine and metabolic disruptions in rat.

Tri-ortho-cresyl phosphate causes glucose intolerance and insulin resistance in mice by inducing oxidative stress.

Toxic effects of organophosphate flame retardants on marine microalgae Chaetoceros muelleri: Insights from physiological and transcriptomic analyses.

Simultaneous determination of 11 organophosphorus flame retardants and 6 metabolites in human urine by ultra-performance liquid chromatography tandem mass spectrometry.

Organophosphorus flame retardants (OPFRs) are emerging alternatives to halogenated compounds, yet their environmental toxicity remains underexplored. This study evaluated the developmental toxicity of two aryl-OPFRs, triphenyl phosphate (TPP) and tricresyl phosphate (TCP), in zebrafish (Danio rerio) from 2 h to 5 days post fertilization (hpf–dpf). Survival, hatching rate, and malformations were assessed across concentrations of 250–1000 µg/L, alongside with gene expression analysis at 5 dpf (250 and 500 µg/L) targeting detoxification (ces2), immune responses (il1β, casp9), and epigenetic markers (dnmt1, dnmt3). In vitro enzymatic assays evaluated interactions of both aryl-OPFRs with carboxylesterase (CE) and acetylcholinesterase (AChE) enzymes. While no significant morphological effects were observed, TPP showed higher toxicity than TCP. Notably, TCP (500 µg/L) downregulated genes linked to metabolism and immunity. CE activity and ces2 modulation may suggest CE as a potential biomarker for aryl-OPFR exposure. These findings, although at concentrations above the environmental ones, may be valuable for mechanistic purposes and underscore the need for further investigation in developmental toxicity given their lipophilic nature and distinct molecular responses.

Mechanistic understanding of the toxic effects of tri-n-butyl phosphate (TnBP) and tricresyl phosphate (TCP) to Escherichia coli: Evidence from alterations in biomarker expression and perturbations of the metabolic network.

A mechanistically-anchored and human stem cell-based in vitro test battery for assessing liver steatogenic potential of chemicals.

The maternal–fetal environment is influenced by multiple factors, including nutrition and environmental contaminants, which can impact long-term development. Perinatal exposure to organophosphate flame retardants (OPFRs) disrupts energy homeostasis and causes maladaptive behaviors in mice. Maternal obesity affects development by impairing blood–brain barrier (BBB) formation, influencing brain regions involved in energy regulation and behavior. This study examined the combined effects of maternal obesity and perinatal OPFR treatment on offspring development. Female mice were fed either a low-fat (LFD) or a high-fat diet (HFD) for 8 weeks, mated, and treated with either sesame oil or an OPFR mixture (tris(1,3-dichloro-2-propyl)phosphate, tricresyl phosphate, and triphenyl phosphate, 1 mg/kg each) from gestational day 7 to postnatal day 14. Results showed that both maternal diet and OPFR treatment disrupted blood–brain barrier integrity, energy balance, and reproductive gene expression in the hypothalamus of neonates. The expression of hepatic genes related to lipid and xenobiotic metabolism was also altered. In adulthood, LFD OPFR-treated female offspring exhibited increased avoidance behavior, while HFD OPFR-treated females demonstrated memory impairments. Metabolic assessments revealed decreased energy expenditure and nighttime activity in LFD OPFR-treated females. These findings suggest that maternal diet and OPFR treatment alter hypothalamic and liver gene expression in neonates, potentially leading to long-term metabolic and behavioral changes.

Tri-ortho-cresyl phosphate (TOCP) is a widely used organophosphorus compound in industry and agriculture, but its immunotoxicity has not been thoroughly investigated. Therefore, this study aimed to assess the immunotoxicity of TOCP in mice by examining changes in immune cell populations and histopathological alterations in the spleen. Male ICR mice were administered TOCP via daily oral gavage at doses of 200 and 400 mg/kg body weight (BW)/d for 28 days to evaluate its effects on immune cell populations in blood and spleen. TOCP treatment at 400 mg/kg BW/d reduced white blood cell counts by 18% and decreased lymphocyte counts by 10.5% compared to the control group. Specifically, CD3+CD4+ Tcell counts in blood decreased by 17.4%. In the spleen, TOCP exposure reduced the proportion of T cells by 13.3%. TOCP also disrupted the structural integrity of the splenic white pulp. Invitro the TOCP metabolite cresyl saligenic phosphate (CBDP) inhibited splenic lymphocyte proliferation, selectively increasing Tcell proportions by 21.25% and inhibiting Bcell proportions by 13.18%, different from invivo findings. This suggests that the reduction of T cells observed invivo may not be solely due to direct cytotoxic effects of TOCP on T cells. These observed changes in immune cell counts and spleen histology indicate that TOCP has a systemic immunotoxicity invivo, which could lead to compromised immune surveillance and defense function.

Neuroprotective effect of copper on neurotoxicity of TOCP in vivo.

Occurrence and risk assessment of organophosphorus esters in drinking water collected from water dispenser systems in Japan.

Toxicological effects, bioaccumulation, and metabolic pathways of tricresyl phosphate in Scenedesmus obliquus.

Long-term exposure to environmentally relevant concentrations of tri-m-cresyl phosphate induces fecundity decline and gonadal dysplasia by disrupting reproductive endocrine homeostasis.

A cyclase-phosphotriesterase (C-PTE) from Ruegeria pomeroyi DSS-3 has recently been identified for its capacity to detoxify several organophosphate compounds. However, several aspects of this enzyme remain unexplored, such as its activity with industrial organophosphates, its molecular structure, and its thermostability. In this work, the crystal structure of C-PTE is reported, which is solved to 2.3 Å resolution, providing insight into the enzyme's mechanism of action, revealing a binuclear Zn2+ active site and distant similarity to other phosphotriesterases from the amidohydrolase superfamily. It is shown that C-PTE catalyzes the hydrolysis of the OP plasticizers triphenyl phosphate (TPhP) and tris(2-chloropropyl) phosphate (TCPP), albeit with low efficiency, but not the sterically bulkier tri-o-tolyl phosphate (ToTP). Finally, it is demonstrated that, even though Ruegeria pomeroyi DSS-3 is not a thermophile, C-PTE exhibits remarkable thermostability and retains structure up to 90 °C. Overall, these findings advance the understanding of C-PTE, suggesting that it is a good candidate for engineering owing to its thermostability and that it could contribute to bioremediation strategies to reduce the impact of pollution by industrial organophosphates.

Significant numbers of aircrew and jet airline passengers are affected by post-flight symptoms of ill health, usually nowadays labelled "aerotoxic syndrome". It could be inferred from a large passenger survey carried out in the Netherlands that up to 50% of flights may engender malaise to varying degrees, and up to 50% of the population might be susceptible to suffering from actual intoxication from the contaminants known to occur in aircraft cabin air. In-flight measurements of its composition have revealed the presence of known neurotoxins, notably tricresyl phosphate and carbon monoxide, both of which can enter the cabin air as it is bled off the main engines. This study reviews the quantitative aspects of this evidence and estimates the susceptibility of the population to neurological damage at the measured levels of contamination, its typical impacts on health, and the likelihood and timescales of post-exposure recovery. Airworthiness directives already mandate that crew and passenger compartment air must be free from harmful or hazardous vapours and gases, but uncertainty regarding the nature of these particular hazards has led to this important aspect of airworthiness having been hitherto unduly neglected. The continuing exponential growth of air passenger traffic means that cabin air contamination will eventually become a major public health hazard if effective action is not taken, some possible courses of which are discussed.

Aryl organophosphate esters (AOPEs) have been widely detected in environmental media and human samples, and increasing evidence shows that AOPEs induce adverse effects on reproductive health. This Review summarizes the exposure levels, reproductive toxicity data, and underlying mechanisms of three legacy AOPEs, including triphenyl phosphate (TPHP), 2-ethylhexyl diphenyl phosphate (EHDPP), and tricresyl phosphate (TCrP). Reproduction-related nuclear receptors (RrNRs) were concluded to play important roles in the reproductive toxicity induced by AOPEs, as all three typical AOPEs and their hydroxylated metabolites elicit binding affinity to RrNRs. We further investigated the RrNRs binding ability of the other 55 emerging AOPEs (eAOPEs) through molecular docking and found most eAOPEs (54/55) showed potential binding ability to RrNRs, especially to estrogen receptor α. This Review helped us to comprehensively understand the adverse effects of AOPEs on reproduction and predict the potential health risk of eAOPEs. AOPEs are easily metabolized in organisms, and their hydroxylated metabolites even show more potency to bind RrRNs. This Review also highlights the necessity to take the contribution of hydroxylated metabolites into account in future research.

Repression of bile salt efflux pump expression by tri-ortho-cresyl phosphate in cultured human hepatic cells.