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Pesticide application is used in horticulture to reduce plant damage from organisms such as insects and mites. Systemic insecticides are highly efficacious and readily taken up by plant tissues. However, pesticide-treated plants may impose risks to nontarget insects or other organisms within ecosystems. In this study, insecticide residues in nectar, leaves, and flower petals of the horticulturally significant herbaceous annual snapdragon, Antirrhinum majus (Lamiales: Plantaginaceae), were assessed at two locations over several weeks following foliar and drench treatment with five systemic insecticides. Concentrations of the insecticides were determined by liquid chromatography-mass spectrometry. The independent effects Application Method, Application Rate, and Time were statistically significant among all active ingredients in the three matrices in both sites in California (CA) and New Jersey (NJ). The interaction effects were also generally statistically significant in the CA site but less consistently so in the NJ site, dependent on the active ingredient and matrix. Post hoc analyses found the highest residue concentrations in leaves and the lowest in nectar, a trend generally consistent over time regardless of active ingredient for both the CA and NJ sites. The results of this study are discussed in the context of conserving pollinators and other beneficial insects. It is recommended that similar studies should be implemented in different geographical regions and climates, along with multiyear studies for perennial ornamental plants. [ABSTRACT FROM AUTHOR]

Heterocyclic aromatic amines (HAAs) are carcinogenic and mutagenic compounds formed by the cooking of meat and combustion of biomass. There are relatively few data on HAAs in atmospheric particulate matter (PM). We developed an analytical method using high performance liquid chromatography – tandem mass spectrometry (tandem quadrupole, HPLC-MS/MS(QqQ)) to analyze PM samples for 12 HAAs. We applied this method to an urban air standard reference material and wildfire-impacted PM2.5 from the 2018 wildfire season in Northern California. The PM sample matrix adversely impacted the MS/MS response, with high levels of ion suppression for sample masses >4 mg and higher ion suppression in wildfire-impacted particulate matter compared with the standard reference material. Despite detection limits at the low ng level, no HAAs were detected in the standard reference material, but β-carboline norharman (0.34 ng/m3) was detected in one wildfire sample. [ABSTRACT FROM AUTHOR]

Residential use of pesticides has been associated with increased risk of childhood acute lymphoblastic leukemia (ALL). We evaluated determinants of glyphosate concentrations in house dust and estimated ALL risk in the California Childhood Leukemia Study (CCLS). The CCLS is a population-based case-control study of childhood leukemia in California. Among those < 8-years (no move since diagnosis/reference date), we collected dust (2001–2007) from the room where the child spent the most time while awake and measured > 40 pesticides. Three-to-eight years later, we collected a second sample from non-movers. We used Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry to measure glyphosate (µg/g dust) for 181 ALL cases and 225 controls and for 45 households with a second dust sample. We used multivariable Tobit regression to evaluate determinants of glyphosate concentrations. Odds ratios (ORs) and 95 % confidence intervals (CI) were calculated for ALL and quartiles of the concentration (first samples) using unconditional logistic regression. We computed the within- and between-home variance and intraclass correlation coefficient (ICC). Glyphosate was frequently detected (cases: 98 %; controls: 99 %). Higher concentrations were associated with occupational pesticide exposure, nearby agricultural use, treatment for lawn weeds and bees/wasps, and sampling season. Increasing concentrations were not associated with ALL risk (adjusted OR Q4vsQ1 = 0.8, CI: 0.4–1.4). We observed similar null associations for boys and girls, Hispanics and non-Hispanic whites, and among those who resided in their home since birth (76 cases/117 controls) or age two (130 cases/176 controls). The ICC was 0.32 indicating high within-home temporal variability during the years of our study. We observed higher concentrations in homes associated with expected predictors of exposure but no association with childhood ALL risk. Due to continuing use, potential exposure to young children is high. It will be important to evaluate risk in future studies with multiple dust measurements or biomarkers of exposure. [ABSTRACT FROM AUTHOR]

Alkyl- and aryl-esters of phosphoric acid (both halogenated and non-halogenated) are mainly used as flame retardants (FRs), among other applications, in furniture and consumer products and they are collectively known as organophosphate flame retardants (OPFRs). The absorption, biotransformation or elimination of many of these chemicals in humans and their possible health effects are not yet well known. A major reason for the limited information is the nature of these compounds, which causes several technical difficulties in their isolation and sensitive determination. A novel analytical liquid chromatography tandem mass spectrometry (LC–MS/MS) method for the accurate and sensitive determination of four urinary OPFR metabolites: bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), bis(2-chloroethyl) phosphate (BCEP), bis(1-chloro-2-propyl) phosphate (BCIPP), and diphenyl phosphate (DPhP), using mixed-mode solid phase extraction and isotope. For the first time all four analytes can be identified in one chromatographic run. An extensive investigation of method development parameters (enzymatic hydrolysis, matrix effects, process efficiency, sources of background interferences, linearity, accuracy, precision, stabilities and limits of detection and quantification) was performed in order to address previously reported method inconsistencies and select a process with the highest accuracy and sensitivity. Chromatographic separation was achieved on a Luna C 18 (2) (2.00 mm × 150 mm, 3 μm) with mobile phase 80:20 v/v water: MeOH and MeOH: water 95:5 v/v, both containing 1 mM tributylamine and 1 mM acetic acid. Limits of detection were 0.025 ng mL −1 for BDCIPP and BCIPP and 0.1 ng mL −1 for DPhP and BCEP. Absolute recoveries of all four analytes and their labeled compounds were in the range of 88–107%. The method was tested on 13 adult California urine samples. BCEP was detected at 0.4–15 ng mL −1 with a geometric mean (GM): 1.9 ng mL −1 ; BDCIPP at 0.5–7.3 ng mL −1 , (GM: 2.5 ng mL −1 ) and DPhP at

Background: The Hooked on Nicotine Checklist (HONC) has been used to assess nicotine dependence (loss of autonomy over tobacco) among adolescents. Existing HONC validation studies for non-cigarette products, such as electronic cigarettes (e-cigarettes), have generally not considered biomarkers of nicotine exposure.Methods: Within a cross-sectional sample of California (USA) high school students (total N = 1396; mean age 15.2 years; 56% female; 54% Hispanic/Latinx), self-reported past 30-day users of any tobacco (including e-cigarettes) completed a modified 10-item HONC questionnaire and provided saliva samples (N = 318 samples, including N = 234 exclusive past 30-day e-cigarette users). Samples were analyzed for cotinine using liquid chromatography-tandem mass spectrometry (lower limit of quantification: 1.0 ng/mL).Results: Across four categories of HONC score corresponding to an increasing number of reported dependence symptoms (scores: 0, 1, 2-4, 5-10), the prevalence of quantifiable salivary cotinine increased among past 30-day tobacco users (20%, 21%, 38%, 55%, respectively, P-for-trend < 0.001) and among past 30-day exclusive e-cigarette users (15%, 22%, 31%, 42%, respectively, P-for-trend = 0.001). Among participants with quantifiable cotinine levels, HONC total score and cotinine were positively correlated among past 30-day tobacco users (n = 89; Spearman rho = 0.449; P < 0.001) and past 30-day exclusive e-cigarette users (n = 49; Spearman rho = 0.520; P < 0.001). HONC score was also associated with past 30-day frequency of tobacco product use and reported use of tobacco within 30 min of waking.Conclusions: These results support the validity of HONC to assess nicotine dependence among adolescents. Dependence symptoms may be experienced at low levels of nicotine exposure. [ABSTRACT FROM AUTHOR]

Benzophenone (BP)-type UV filters are widely used in a variety of personal care products for the protection of skin and hair from UV irradiation. Despite the estrogenic potencies of BP derivatives, few studies have examined the occurrence of these compounds in human matrices. Furthermore, associations among exposure to these compounds and estrogen-dependent diseases (such as endometriosis) have not been examined previously. In this study, we determined the concentrations of five BP derivatives, 2-hydroxy-4-methoxybenzophenone (2OH-4MeO-BP), 2,4-dihydroxybenzophenone (2,4OH-BP), 2,2'-dihydroxy-4-methoxybenzophenone (2,2'OH-4MeO-BP), 2,2',4,4'-tetrahydroxybenzophenone (2,2',4,4'OH-BP), and 4-hydroxybenzophenone (4OH-BP), in urine collected from 625 women in Utah and California, using liquid chromatography (LC)-tandem mass spectrometry (MS/MS). The association of urinary concentrations of BP derivatives with an increase in the odds of a diagnosis of endometriosis was examined in 600 women who underwent laparoscopy/laparotomy (n = 473: operative cohort) or pelvic magnetic resonance imaging (n = 127: population cohort), during 2007-2009. 2OH-4MeO-BP, 2,4OH-BP, and 4OH-BP respectively were detected in 99.0%, 93.3%, and 83.8% of the urine samples analyzed, whereas the detection rates for 2,2',4,4'OH-BP and 2,2'OH-4MeO-BP were below 6.0%. Significant regional differences (higher concentrations in California) and monthly variations (higher concentrations in July and August) were found for urinary concentrations of 2OH-4MeO-BP and 2,4OH-BP. In addition, urinary concentrations of 2OH-4MeO-BP and 2,4OH-BP tended to be higher in more affluent, older, and leaner women. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for the urinary concentrations of BP derivatives and the odds of an endometriosis diagnosis; ORs increased across quartiles of 2OH-4MeO-BP and 2,4OH-BP concentrations, but a significant trend was observed only between 2,4OH-BP and the odds of an endometriosis diagnosis in the operative cohort (OR = 1.19; 95% CI = 1.01, 1.41). When women in the highest quartile of 2,4OH-BP concentrations were compared with women in the first three quartiles, the OR increased considerably (OR = 1.65; 95% CI = 1.07, 2.53). Given that 2,4OH-BP possesses an estrogenic activity higher than that of 2OH-4MeO-BP, our results invite the speculation that exposure to elevated 2,4OH-BP levels may be associated with endometriosis. [ABSTRACT FROM AUTHOR]

• Eleven pesticides and their metabolites were analyzed in urine of endometriosis cohorts. • Six pesticides/metabolites had a detection frequency ≥95% in urine. • Odds ratios for endometriosis diagnosis were significant for IMPY and TCPY. • Exposure to diazinon and chlorpyrifos may be associated with endometriosis. Endometriosis is a hormone-responsive gynecologic disease, signifying its connotations across a woman's life span. Previous studies suggested that endocrine disrupting chemicals were risk factors for endometriosis. Nevertheless, little is known on exposure to organophosphate, pyrethroid and phenoxy acid pesticides on endometriosis diagnosis. In this study, we determined the concentrations of 11 pesticides, metabolites of organophosphate and pyrethroid insecticides, and phenoxy herbicides, in urine collected from 619 reproductive-age women in Utah and California, using liquid chromatography-tandem mass spectrometry. The association of urinary concentrations of pesticides with an increase in the odds of endometriosis diagnosis was examined in 594 women who underwent laparoscopy/laparotomy (operative cohort: n = 471) or pelvic magnetic resonance imaging (population cohort: n = 123), during 2007–2009. 2-Isopropyl-4-methyl-6-hydroxypyrimidine (IMPY), malathion dicarboxylic acid (MDA), para -nitrophenol (PNP), 3,5,6-trichloro-2-pyridinol (TCPY), 3-phenoxybenzoic acid (3-PBA), and 2,4-dichlorophenoxyacetic acid (2,4-D) were detected in ≥95% of the urine samples analyzed. Urinary concentrations of IMPY, MDA, PNP, 3-PBA and 2,4-D tended to be higher in younger, non-Hispanic black, nulliparous and less affluent women. IMPY was the most dominant compound in urine followed by PNP and TCPY. When women in the 4th quartile of IMPY and the 2nd quartile of TCPY concentrations (μg/g creatinine) were compared with women in the 1st quartile, the odds ratios (ORs) for diagnosis of endometriosis increased significantly in unadjusted models (IMPY OR = 1.89, 95% confidence interval (Cl) = 1.12–3.20; TCPY OR = 1.65, 95% Cl = 1.02–2.69) for the operative (n = 471) and entire data set (n = 594), respectively. Our results suggest that exposure to elevated concentrations of diazinon (the parent compound of IMPY) and chlorpyrifos and chlorpyrifos-methyl (parent compounds of TCPY) may be associated with endometriosis. [ABSTRACT FROM AUTHOR]

Introduction: Thirdhand smoke (THS) residue lingers for months in homes of former smokers and may play a role in relapse after smoking cessation. This study examined the association between THS pollution as measured by the level of nicotine in house dust and continued abstinence from smoking.Methods: Participants were 65 cigarette smokers who reported they were enrolled in any type of smoking cessation program, had set a specific date to quit, and had biochemical verification of continuous abstinence at 1-week (W1), 1-month (M1), 3-months (M3), or 6-months (M6) after their quit date. House dust samples collected at baseline before quitting were analyzed for nicotine concentration (μg/g) and nicotine loading (μg/m2) using liquid chromatography-tandem mass spectrometry (LC-MS/MS).Results: Controlling for age, gender, overall and indoor smoking rates, and years lived in their home, dust nicotine concentration and loading predicted abstinence at W1, M1, M3, and M6. A 10-fold increase in dust nicotine loading and concentration were associated with approximately 50% lower odds of remaining abstinent.Conclusions: Findings suggest nicotine in house dust may play a role in facilitating relapse after smoking cessation. Additional research is warranted to investigate the causal role of THS residue in homes of former smokers on cravings and continued abstinence. [ABSTRACT FROM AUTHOR]