Comprehensive risk assessment of the inhalation of plasticizers from the use of face masks.

Disposable masks, formed mainly from polymers, often incorporate various chemical additives to enhance their performance. These additives, which include plasticizers, may be released during mask usage, presenting a novel source of human exposure to these compounds. In this study, the presence of 16 organophosphate esters (OPEs), 11 phthalates, and four alternative plasticizers, in four various types of face masks, were studied, as well as their release during simulated mask use (artificial laboratory conditions). Total plasticizer concentrations exhibited minimal variation across different mask types, with mean values of 7.27 µg/face mask for surgical, 8.61 µg/face mask for reusable, 11.0 µg/face mask for KN-95, and 13.9 µg/face mask for FFP2 masks. To explore plasticizer release behavior, inhalation experiments were conducted under different conditions. The findings revealed a significant temperature-dependent enhancement in plasticizer release from masks, subsequently increasing human inhalation exposure. The inhalation experiments showed variation in the release percentages, ranging from 0.1 to 95 %, depending on the specific compound and mask type. Notably, OPEs exhibited a mean release percentage of 1.0 %, similar to phthalates, which showed a 1.2 % release. Although alternative plasticizers were less frequently released, they still presented a notable percentage of release of 4.1 %. Daily intake estimations via inhalation ranged from 0.01 to 9.04 ng/kg body weight (bw)/day for these additives. Using these estimations, carcinogenic and non-carcinogenic risks associated with this exposure to these compounds were evaluated. All calculated values for the specific compounds studied in this paper remained below the established threshold limits. However, they do represent an additional exposure pathway that, when considered alongside other more predominant routes such as indoor/outdoor inhalation, dermal absorption, and dietary intake, makes the total exposure worthy of consideration.

Sexual dysfunction in dichlorvos-exposed male Wistar rat is ameliorated by curcumin and associated with the upregulation of testosterone.

Dichlorvos is an organophosphate pesticide that is commonly used for agricultural and domestic control of pests and insects. Despite its usefulness, it exerts reproductive toxicity and induces male sexual dysfunction. On the other hand, curcumin has been reported to improve sexual dysfunction. However, till date, no study has reported the impact of curcumin on dichlorvos-induced sexual dysfunction. This study investigated the effect and associated mechanism of curcumin on dichlorvos-induced sexual dysfunction. Thirty-two male Wistar rats were randomized into four groups; the control (1 mL of olive oil), curcumin-treated (100 mg/kg), DDVP-treated (98.54 g/m3 of dichlorvos by inhalation), and DDVP + Curcumin-treated. Dichlorvos induced sexual dysfunction as depicted by reduced motivation to mate (8.38 ± 0.18 vs. 4.00 ± 0.33, P < 0.0001), prolonged latencies (46.63 ± 1.30 vs. 98.75 ± 1.32, P < 0.0001) and reduced frequencies of mount (14.88 ± 0.52 vs. 8.63 ± 0.38), intromission (9.38 ± 0.50 vs. 3.75 ± 0.31, P < 0.0001), and ejaculation (7.63 ± 0.38 vs. 1.50 ± 0.19, P < 0.0001). These findings were accompanied by suppression of hypothalamic-pituitary-testicular axis, evidenced by marked reductions in circulating FSH (60.00 ± 1.04 vs. 21.13 ± 0.52, P < 0.0001), LH (46.38 ± 1.38 vs. 19.00 ± 0.46, P < 0.0001), and testosterone (6.01 ± 0.50 vs. 0.74 ± 0.05, P < 0.0001). Nonetheless, the administration of curcumin in dichlorvos-exposed rats significantly attenuated dichlorvos-induced sexual dysfunction by improving the assessed indices of male sexual act. Also, curcumin significantly increased serum levels of FSH (21.13 ± 0.52 vs. 47.25 ± 0.10, P < 0.0001), LH (19.00 ± 0.46 vs. 43.00 ± 1.49), and testosterone (0.74 ± 0.05 vs. 3.98 ± 0.08, P < 0.0001). This study revealed that curcumin attenuated dichlorvos-induced sexual dysfunction by activating the hypothalamic-pituitary-testicular axis and upregulating circulating testosterone.

Characteristics and partitions of traditional and emerging organophosphate esters in soil and groundwater based on machine learning.

Organophosphate esters (OPEs) pose hazards to both humans and the environment. This study applied target screening to analyze the concentrations and detection frequencies of OPEs in the soil and groundwater of representative contaminated sites in the Pearl River Delta. The clusters and correlation characteristics of OPEs in soil and groundwater were calculated by self-organizing map (SOM). The risk assessment and partitions of OPEs in industrial park soil and groundwater were conducted. The results revealed that 14 out of 23 types of OPEs were detected. The total concentrations (Σ23OPEs) ranged from 1.931 to 743.571 ng/L in the groundwater, and 0.218 to 79.578 ng/g in the soil, the former showed highly soluble OPEs with high detection frequencies and concentrations, whereas the latter exhibited the opposite trend. SOM analysis revealed that the distribution of OPEs in the soil differed significantly from that in the groundwater. In the industrial park, OPEs posed acceptable risks in both the soil and groundwater. The soil could be categorized into Zone I and II, and the groundwater into Zone I, II, and III, with corresponding management recommendations. Applying SOM to analyze the characteristics and partitions of OPEs may provide references for other new pollutants and contaminated sites.

Evaluation and implications of organophosphate pesticide residues in cabbage (Brassica oleracea).

The improper application of pesticides in cultivating vegetables has resulted in the buildup of pesticide residues on vegetables. This study evaluated organophosphate pesticide residue levels in cabbage with specific objectives of investigating the varieties of organophosphate pesticides employed by farmers and their awareness, assessing residue levels on cabbage using semi-structured questionnaires, and determining the distribution of pesticide residues within the layers of the cabbage head using 50 cabbage samples randomly collected from farmers from 14 cabbage-producing communities. The findings indicated that 98 % of the farmers applied pesticides in the morning, whereas 24 % preferred evening application. Meanwhile, 22 % applied pesticides twice in a day. Also, 18 % combined pesticides, 40 % applied 20 ml during the application, 72 % chose a particular pesticide based on the expected efficiency, 46 % applied pesticides between 1 and 5 times in a season and 66 % sprayed between 7 and 14 days. Pyrinex 48 EC and Perferthion emerged as the predominant organophosphates, with usage rates of 10 % and 12 % respectively. Also, eleven (11) organophosphate pesticide residues were identified in the cabbage samples. Profenofos and chlorpyrifos exhibited the highest concentrations of pesticide residues, with levels reaching 0.02 mg/kg, with 56.6 % of the samples containing chlorpyrifos pesticide residue. Nevertheless, all the identified pesticide residues did not exceed the maximum residue limits for cabbage. The study analysis disclosed the presence of various organophosphate pesticide residues in the first 10 layers of cabbage. However, it was noted that the innermost layers might not contain any detectable pesticide residues. The findings highlight the need for farmers to use pesticides judiciously and follow recommended application practices to minimize vegetable residues.

Severe and Recurrent Acute Kidney Injury Following Dichlorvos Exposure - A Case Report.

Dichlorvos, an organophosphate compound, has the potential to cause acute kidney injury (AKI) besides its well-known neuromuscular complications. We report a case of severe-recurrent AKI that progressed to end-stage-renal-disease (ESRD) following accidental exposure to Dichlorvos. A 52-year-old male farmer presented with breathlessness after accidental exposure while spraying in the field. He required mechanical ventilation due to allergic pneumonitis and developed anuric AKI, requiring renal replacement therapy (RRT). Biopsy revealed severe acute tubulointerstitial nephritis (ATIN), which responded to steroids, and the patient became dialysis-independent by 4 weeks. Two weeks later, the patient had recurrent AKI requiring RRT. A repeat biopsy revealed severe ATIN. However, despite steroid treatment, he progressed to ESRD. Organophosphate compounds can cause renal injury with a wide spectrum of presentations, ranging from subclinical AKI to severe dialysis-dependent renal failure, which may eventually progress to end-stage renal disease.

Associations of prenatal exposure to individual and mixed organophosphate esters with ADHD symptom trajectories in preschool children: The modifying effects of maternal Vitamin D.

BACKGROUND: Organophosphate esters (OPEs) are a class of environmental chemicals with endocrine-disrupting properties. Epidemiologic studies have demonstrated that prenatal OPEs exposure is associated with neurodevelopmental disorders in offspring. However, studies assessing the effects of prenatal OPEs exposure on the dynamic changes in attention deficit hyperactivity disorder (ADHD) symptoms in preschoolers are scarce. Since vitamin D has been demonstrated to have a "neuroprotective" effect, the modifying effects of maternal vitamin D were estimated. METHODS: The present study included 2410 pregnant women from the Ma'anshan Birth Cohort. The levels of OPEs in the mothers' urine were examined in the three trimesters. The Chinese version of the Conners Abbreviated Symptom Questionnaire was used to examine preschoolers' ADHD symptoms at 3, 5, and 6 years of age. ADHD symptom trajectories were fitted via group-based trajectory modeling. We used multinomial logistic regression, Bayesian kernel machine regression, quantile-based g-computation, and generalized linear models to assess individual and mixed relationships between OPEs during pregnancy and preschoolers' ADHD symptoms and trajectories. RESULTS: Preschoolers' ADHD symptom scores were fitted to 3 trajectories, including the low-score, moderate-score, and high-score groups. First-trimester dibutyl phosphate (DBP), second-trimester bis(2-butoxyethyl) phosphate (BBOEP), and third-trimester diphenyl phosphate (DPHP) were associated with an increased risk in the high-score group (p < 0.05). BBOEP in the third trimester was associated with decreased risk in the moderate-score group (OR = 0.89, 95% CI: 0.79, 1.00). For mothers with 25(OH)D deficiency, a positive relationship was observed between OPEs during pregnancy and symptom trajectories. Our results did not reveal any mixed effects of OPEs on ADHD symptom trajectories. CONCLUSION: Prenatal exposure to OPEs had heterogeneous associations with ADHD symptom trajectories in preschoolers. Additionally, the effect of individual OPEs on symptom trajectories was intensified by vitamin D deficiency.

A Comprehensive Physiotherapy Approach to Regain Functional Independence in Intermediate Syndrome Secondary to Organophosphate Poisoning: A Case Report.

Organophosphate poisoning (OPP) remains a significant public health issue globally, particularly in middle- and low-income countries. This study aimed to assess the effectiveness of physiotherapy interventions in managing patients with OPP, focusing on reducing the severity of intermediate syndrome symptoms and associated complications such as respiratory muscle weakness and bilateral loculated pleural effusions. A 48-year-old male with a history of alcohol consumption was transferred to the medicine intensive care unit due to poison ingestion. The patient exhibited symptoms of respiratory distress and decreased consciousness, necessitating intubation and mechanical ventilation. Physiotherapy interventions included patient education, secretion mobilization, vital capacity improvement, secondary complication prevention, chest expansion exercises, dyspnea-relieving positions, and mobilization. The patient's progress was monitored using various scales, including the Functional Independence Measure Scale, ICU Mobility Scale, and Chelsea Critical Care Physical Assessment Tool. Significant improvements in functional independence, mobility, and psychological well-being were observed throughout the intervention period. This study highlights the importance of physiotherapy in the comprehensive management of OPP, emphasizing its role in mitigating respiratory complications and improving overall functional outcomes.

Spatial variation, emissions, transport, and risk assessment of organophosphate esters in two large petrochemical complexes in southern China.

Organophosphate esters (OPEs) serve as significant flame retardants and plasticizers in various petrochemical downstream products. The petrochemical industry could be a potential source of atmospheric OPEs, but their emissions from this industry are poorly understood. The present study revealed the spatial variation, emission, and atmospheric transport of traditional and novel OPEs (TOPEs and NOPEs, respectively) in atmospheric particulate matter (PM) across Hainan and Guangdong petrochemical complexes (HNPC and GDPC, respectively) in southern China. The total concentrations of TOPEs ranged from 232 to 46,002 pg/m3 and from 200 to 20,347 pg/m3 in the HNPC and GDPC, respectively, which were substantially higher than those of NOPEs (HNPC: 23.5-147 pg/m3, GDPC: 13.9-465 pg/m3). Enterprises involved in the production of downstream petrochemical products presented relatively high concentrations of OPEs, indicating evident emissions of these pollutants in the petrochemical industry. The correlations of PM-bound OPEs in the atmosphere are determined mainly by their coaddition to industrial products or their coexistence in technical mixtures. The annual emissions of TOPEs and NOPEs in the HNPC were 42.6 kg and 0.34 kg, respectively, and those in the GDPC were 116 kg and 1.85 kg, respectively. OPEs from the HNPC can reach Vietnam, Cambodia, and Guangxi Province, China, and those from the GDPC can reach Guangxi Province and Hunan Province via atmospheric transmission after 24 h of emission. The OPE concentrations reaching the receptor regions were generally less than 3.20 pg/m3. Risk assessment revealed that OPE inhalation exposure on two petrochemical complexes likely poses minor risks for people living in the study areas, but the risk resulting from two chlorinated OPEs should be noted since they are close to the threshold values. This study has implications for enhancing control measures for OPE emissions to reduce health risks related to the petrochemical industry.

Association between blood lipid levels in early pregnancy and urinary organophosphate metabolites in the Japan Environment and Children's Study.

BACKGROUND: High low-density lipoprotein cholesterol levels (LDL-C) during pregnancy have been associated with adverse pregnancy and offspring outcomes. While previous studies have suggested a potential link between organophosphate pesticide (OPP) exposure and higher LDL-C in the general population and agricultural workers, the relationship in pregnant women and the effect of body mass index on this relationship remain unclear. We examined the association between the urinary concentrations of OPP metabolites (dialkylphosphates) and blood lipid levels in pregnant women. METHODS: We used data from the Japan Environment and Children's Study, which included 5,169 pregnant women with urinary dialkylphosphate data. We examined the association between urinary concentrations of six dialkylphosphates (DEP, DETP, DEDTP, DMP, DMTP, DMDTP) and blood lipid levels (LDL-C, total cholesterol, high-density lipoprotein cholesterol, and triglycerides) during the first trimester using multiple linear regression under a Bayesian paradigm. We examined the association between high LDL-C, defined as ≥90th percentile of LDL-C, and urinary dialkylphosphate concentrations, using multiple logistic regression under a Bayesian paradigm. These analyses were repeated in underweight, normal-weight, and overweight participants. RESULTS: DEP, DMP, and DMTP were detected in >50 % of the participants. Multiple linear regression analyses did not show associations between LDL-C and these dialkylphosphates. Stratified analyses showed a positive association between DEP and LDL-C in overweight women (beta coefficient = 2.13, 95 % credible interval = 0.86-3.38, probability of direction (PD) = 100 %); however, the association was not significant (percentage in region of practical equivalence (% in ROPE) = 84.0). Higher DEP was significantly associated with high LDL-C (odds ratio = 1.32, 95 % credible interval = 1.13-1.55, PD = 100 %, % in ROPE = 0.2). CONCLUSIONS: Among overweight pregnant women in the first trimester, higher urinary DEP concentrations were associated with high LDL-C. The effects of OPP on blood lipid profiles merit further investigation.

Exposure to organophosphate esters and early menopause: A population-based cross-sectional study.

Organophosphate esters (OPEs), increasingly used as new flame retardants and plasticizers in various products, have been found to have reproductive toxicity with overt endocrine disruption potential, yet the relationship between OPEs and early menopause remains unexplored. In the present study, we included 2429 women who participated in the U.S. National Health and Nutrition Examination Survey data (2011-2020) and had data of five urinary OPE metabolite levels and information of menopause characteristics, to investigate the associations of OPEs exposure with premature ovarian insufficiency (POI) and age of menopause. Multivariable adjusted linear and logistic regression were used to assess the associations of urinary OPE metabolites with age of menopause and POI, respectively. Quantile g computation (QGC) models were used to assess the relative contribution of individual metabolites to associations of OPE metabolites mixture. After adjusting for covariates, urinary bis(2-chloroethyl) phosphate (BCEP) concentration was inversely associated with menopause age (ß = - 0.21; 95% confidence interval (CI): 0.41, - 0.002). Higher urinary BCEP level (>median) was associated with earlier age at menopause (ß = -1.14, 95% CI: 1.83, - 0.46), and elevated odds of having POI (OR = 1.93; 95% CI: 1.02, 3.66). These associations were robust to the further adjustment of cardiometabolic diseases and related traits (e.g., body mass index). Further QGC analyses confirmed that BCEP was the dominant metabolite contributing most to the associations of OPEs mixture with age of menopause (weight = 49.5%) and POI (weight = 75.1%). No significant associations were found for the other four OPE metabolites. In this cross-sectional study, urinary BCEP level was associated with earlier menopause and increased odds of POI, highlighting the potential negative impacts of this chemical and its parent compound tris(2-chloroethyl) phosphate on ovarian function. Further studies are required to validate our findings and reveal potential underlying mechanisms.

Structure-dependent destructive adsorption of organophosphate flame retardants on lipid membranes.

The widespread use of organophosphate flame retardants (OPFRs), a serious type of pervasive environmental contaminants, has led to a global concern regarding their diverse toxicities to living beings. Using a combination of experimental and theoretical approaches, we systematically studied the adsorption, accumulation, and influence of a series of OPFRs on the lipid membranes of bacteria and cells. Our results revealed that OPFRs can aggregate in lipid membranes, leading to the destruction of membrane integrity. During this process, the molecular structure of the OPFRs is a dominant factor that significantly influences the strength of their interaction with the lipid membrane, resulting in varying degrees of biotoxicity. Triphenyl phosphate (TPHP), owing to its large molecular size and strong hydrophobicity, causes severe membrane disruption through the formation of nanoclusters. The corresponding severe toxicity originates from the phase transitions of the lipid membranes. In contrast, smaller OPFRs such as triethyl phosphate (TEP) and tris(2-chloroethyl) phosphate (TCEP) have weaker hydrophobicity and induce minimal membrane disturbance and ineffective damage. In vivo, gavage of TPHP induced more severe barrier damage and inflammatory infiltration in mice than TEP or TCEP, confirming the higher toxicity of TPHP. Overall, our study elucidates the structure-dependent adsorption of OPFRs onto lipid membranes, highlighting their destructive interactions with membranes as the origin of OPFR toxicity.

Nationwide Investigation on Organophosphate Flame Retardants in Tea from China: Migration from Packaging Materials and Implications for Global Risk Assessment.

In this study, we measured 15 common organophosphate flame retardants (OPFRs) in six categories of tea samples across China. OPFRs were found in all the tea samples, with the total concentrations of OPFRs (∑OPFRs) at 3.44-432 ng/g [geometric mean (GM): 17.6 ng/g]. Triphenyl phosphate (TPhP) was the dominant OPFR, accounting for 39.0-76.2% of ∑OPFRs across all tea categories. The potential factors influencing the residual OPFRs in tea were thoroughly examined, including the agricultural environment, fermentation, and packaging of teas. Tea packaging materials (TPMs) were then identified as the primary sources of OPFRs in teas. The migration test revealed that OPFRs with lower molecular weights and log Kow values exhibited a higher propensity for facilitating the migration of OPFRs from TPMs to teas. The estimated daily intakes of OPFRs from teas were relatively higher for the general populations in Mauritania, Gambia, Togo, Morocco, and Senegal (3.18-9.79 ng/kg bw/day) than China (3.12 ng/kg bw/day). The health risks arising from OPFRs in Chinese teas were minor. This study established a baseline concentration and demonstrated the contamination sources of OPFRs in Chinese tea for the first time, with an emphasis on enhancing the hygiene standards for TPMs.

Co-exposure with Copper Alters the Uptake, Accumulation, Subcellular Distribution, and Biotransformation of Organophosphate Triesters in Rice (Oryza sativa L.).

This study investigated the uptake pathways, acropetal translocation, subcellular distribution, and biotransformation of OPEs by rice (Oryza sativa L.) after Cu exposure. The symplastic pathway was noted as the major pathway for the uptake of organophosphate triesters (tri-OPEs) and diesters (di-OPEs) by rice roots. Cu exposure enhanced the accumulation of tri-OPEs in rice roots, and such enhancement was positively correlated with Cu concentrations, attributing to the Cu-induced root damage. The hydrophilic Cl-OPEs in the cell-soluble fraction of rice tissues were enhanced after Cu exposure, while the subcellular distributions of alkyl- and aryl-OPEs were not affected by Cu exposure. Significantly higher biotransformation rates of tri-OPEs to di-OPEs occurred in leaves, followed by those in stems and roots. Our study reveals the mechanisms associated with the uptake, translocation, and biotransformation of various OPEs in rice after Cu exposure, which provides new insights regarding the phytoremediation of soils cocontaminated with heavy metal and OPEs.

Organophosphorus flame retardants in the Qiantang River of China: occurrence, source and ecological risk assessment.

In recent years, the prevalence and danger of organophosphorus flame retardants (OPFRs) have drawn attention from all around the world. This study examined twenty-five OPFRs observed in water and sediment samples from the Qiantang River in eastern China, as well as their occurrence, spatial distribution, possible origins, and ecological hazards. All the 25 OPFRs were detected in water and sediment samples. The levels of Σ25OPFRs in water and sediment were 35.5-192 ng/L and 8.84-48.5 ng/g dw, respectively. Chlorinated OPFRs were the main contributions in water, whereas alkyl-OPFRs were the most common congeners found in sediment. Spatial analysis revealed that sample locations in neighboring cities had somewhat higher water concentrations of OPFRs. Slowing down the river current and making the reservoir the main sink of OPFRs, the dam can prevent OPFRs from moving via the Qiantang River. Positive matrix factorization indicated that plasticizer in polyvinyl chloride, polyester resins, and polyurethane foam made the greatest contributions in water, whereas polyurethane foam and textile were the predominant source in sediment. Analysis of sediment-water exchange of OPFRs showed that twelve OPFRs in sediments can re-enter into the water body. The risk quotients showed the ecological risk was low to medium, but trixylyl phosphate exposures posed high ecological risk to aquatic organisms.

Pesticide exposure and blood cholinesterase levels among adolescents from farming families in Northern Thailand.

BACKGROUND: Adolescents living in agricultural communities may be at risk for the adverse effects of pesticide exposure because they are involved in agriculture either as a career or to support their families. OBJECTIVE: The purpose of this study was to investigate the association of farm activities related to pesticide exposure on blood cholinesterase (ChE) levels among adolescents from farming families in the north of Thailand. MATERIAL AND METHODS: This cross-sectional study included 336 adolescents aged 12-19 years from farming families in Chiang Dao District, Chiang Mai Province. Data on pesticide exposure was collected using a questionnaire, and blood ChE activity was assessed using a ChE reactive paper test kit via fingerstick blood sampling. RESULTS: Overall, 51.2% of participants had abnormal blood ChE levels. Univariable logistic regression analysis revealed that pesticide-related activities on farms associated with abnormal ChE levels were mixing/spraying (OR=10.54; 95%CI=4.63-23.99), assisting or working in areas with pesticide application (OR=5.54; 95%CI=3.45-8.89), and harvesting (OR=3.70; 95%CI=2.35-5.82). In a multivariable model (Nagelkerke R2=0.374), mixing/spraying (OR=4.90; 95%CI=2.03-11.83) and assisting or working in areas with pesticide application (OR=2.61; 95%CI=1.49-4.57) were significantly associated with abnormal ChE levels, but harvesting (OR=1.48; 95%CI=0.84-2.61) was not significant after adjusting for sex, age in years, and entering or walking through a farm. CONCLUSIONS: The findings indicated that Thai adolescents living in farming families are at risk of pesticide exposure, particularly those involved in agricultural activities such as pesticide applicators. An intervention and measure to raise awareness and reduce the risk of pesticide exposure in adolescents is required.

Organophosphate Esters in Raw Cow Milk and Cow's Drinking Water and Feed from China: Occurrence, Regional Distribution, and Dietary Exposure Assessment.

Organophosphate esters (OPEs) have been widely produced and used, while little is known about their occurrence in the food chain and potential sources. In this study, raw cow milk, cow drinking water, and feed were collected from pastures across China, and OPEs were tested to explore the occurrence and transmission of OPEs in the food chain and to further assess daily OPE intakes for cows and humans via certain food consumption. The median level of ∑OPEs (sum of 15 OPEs) in raw milk was 2140 pg/mL, and tris(1-chloro-2-propyl) phosphate (TCIPP) was the most abundant OPE. Levels of OPEs in water were lower than those in raw milk except for triethyl phosphate (TEP), while levels of most OPEs in feed were significantly higher than those in raw milk (adjusted by dry weight). The estimated dietary intake of OPEs via feed for cows was 2530 ng/kg bw/day, which was much higher than that via water (742 ng/kg bw/day), indicating that feed was a more critical exposure source. For liquid milk consumers, the high-exposure (95th) estimated daily intakes (EDIs) of ∑15OPE were 20 and 7.11 ng/kg bw/day for 3-17 years and adults, respectively, and it is obvious that cows had much heavier OPE intake. Finally, the calculated hazard indexes (HIs) suggested that the intake of OPEs via cow milk consumption would not pose significant health risks to the Chinese population.

Accidental Organophosphate Poisoning in a Toddler: A Case Report.

While accidental poisoning is fairly common in children, the data are sparse when organophosphate (OP) is considered the culprit toxin. Only case reports of such patients from the Southeast Asian Region have been documented, despite it contributing largely to the global burden of organophosphorus poisoning in the adult population. This can be attributed to difficulty in diagnosing children because of varied presentations in the pediatric population and unreliable or unavailable exposure history. We present a case of a 19-month-old toddler who presented to the ED with OP poisoning, which proved to be a diagnostic and management challenge because of more common differentials and the unavailability of a clear history.

Male mice are susceptible to brain dysfunction induced by early-life acephate exposure.

Background: Acephate is a widely used organophosphate insecticide. Exposure to endocrine-disrupting chemicals, such as acephate, can interfere with neurodevelopment in childhood, increasing the risk of higher brain dysfunction later in life. Furthermore, brain dysfunction may be related to chemical exposure-related disturbances in the gut microbiota. However, the effects of early acephate exposure on the brains of adult males and females as well as on the adult gut environment remain poorly understood. Methods: This study investigated the effects of perinatal acephate exposure on the central nervous system and gut microbiota of mice, including sex differences and environmentally relevant concentrations. C57BL/6 N pups were exposed to acephate (0, 0.3, 10, and 300 ppm) via the dam in their drinking water from embryonic day (E) 11.5 to postnatal day 14. We examined its effects on the central nervous system of adult males and females. Results: In the male treatment group, impairments in learning and memory were detected. Immunohistochemical analysis revealed a decrease in SOX2-, NeuN-, DCX-, and GFAP-positive cells in the hippocampal dentate gyrus in males compared to the control group, whereas GFAP-positive cells were fewer in females. In addition, gut microbiota diversity was reduced in both sexes in the experimental group. Conclusion: Our study demonstrates that the effects of early-life exposure to acephate are more pronounced in males than in females and can lead to a lasting impact on adult behavior, even at low doses, and that the gut microbiota may reflect the brain environment.

Organophosphate ester flame retardant chemicals and maternal depression during pregnancy.

BACKGROUND: Depression substantially contributes to pregnancy-related morbidity, and pregnancy is increasingly recognized as a vulnerable window for exposure effects on maternal mental health. Exposures to organophosphate esters (OPEs) are ubiquitous and may have neurotoxic effects; however, their impacts on prenatal depression remain unknown. We evaluated associations of third trimester OPE metabolites on maternal depressive symptoms during pregnancy. METHODS: This study included 422 participants in the Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) cohort, a prospective pregnancy cohort of primarily low-income and Hispanic participants residing in Los Angeles, California. We measured concentrations of nine OPEs in third trimester spot urine samples (mean gestational age = 31.5 ± 2.0 weeks). Using the Center for Epidemiologic Studies-Depression (CES-D) scale, we classified participants as having probable depression during pregnancy (N = 137) or not (N = 285) if one or more CES-D scores administered at each trimester met the suggested cutoff score for clinically significant depressive symptoms (≥16). We estimated associations of prenatal OPE metabolite concentrations in tertiles and risk of prenatal depression using modified Log-Poisson regression. We examined associations of the OPE mixture on depression during pregnancy using Bayesian kernel machine regression (BKMR). RESULTS: Participants with the highest tertiles of DPHP and BDCIPP exposure had a 67% (95% CI: 22%, 128%) and 47% (95% CI: 4%, 108%) increased risk of maternal depressive symptoms during pregnancy, respectively. No associations between other OPE metabolites and maternal depression symptoms were observed. In mixture analyses, we observed a positive and linear association between higher exposure to the OPE metabolite mixture and odds of prenatal maternal depression, primarily driven by DPHP. CONCLUSIONS: Our findings provide new evidence of associations between frequently detected OPE metabolites on maternal depression symptoms during pregnancy. Results could inform future intervention efforts aimed at reducing perinatal maternal depression.

Severe Amitraz Poisoning: A Case of Successful Emergency Intervention.

Amitraz poisoning is being increasingly seen in clinical practice, presenting physicians with challenges due to its rapidity of onset of severe clinical features, its similarity with organophosphate poisoning and the absence of specific antidotes. Early initiation and appropriate treatment are vital for favourable outcomes. Our case report is of a 40-year-old male who presented to us with grave clinical features following deliberate ingestion of Amitraz in a suicidal attempt. On arrival, he had bradycardia, hypotension, respiratory depression, and altered sensorium. Immediate administration of atropine stabilised his vital signs. Laboratory investigations revealed uncommon electrolyte imbalances, which were promptly corrected. The patient received supportive care in the intensive care unit (ICU), regained consciousness within three days, and was discharged after a week of hospitalisation. Despite the rapid onset and severity of symptoms caused by Amitraz poisoning, early intervention and supportive care can lead to a full recovery. This case underscores the importance of promptly recognising Amitraz poisoning and initiating treatment, its similarity with organophosphate poisoning and the role of atropine. Further research is needed to establish comprehensive management guidelines for tackling this emerging poisoning hazard.