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Introduction: Occupational exposure to antineoplastic drugs can lead to long-term adverse effects on workers' health. A reproducible Canadian surface monitoring program was established in 2010. The objective was to describe contamination with 11 antineoplastic drugs measured on 12 surfaces among hospitals participating in this annual monitoring program. Methods: Each hospital sampled six standardized sites in oncology pharmacies and six in outpatient clinics. Ultra-performance liquid chromatography coupled with tandem mass spectrometry was used for cyclophosphamide, docetaxel, doxorubicin, etoposide, 5-fluorouracil, gemcitabine, irinotecan, methotrexate, paclitaxel, and vinorelbine. Platinum-based drugs were analyzed by inductively coupled plasma mass spectrometry; this excludes inorganic platinum from the environment. Hospitals filled out an online questionnaire about their practices; a Kolmogorov–Smirnov test was used for some practices. Results: One hundred and twenty-four Canadian hospitals participated. Cyclophosphamide (405/1445, 28%), gemcitabine (347/1445, 24%), and platinum (71/756, 9%) were the most frequent. The 90th percentile of surface concentration was 0.01 ng/cm² for cyclophosphamide and 0.003 ng/cm² for gemcitabine. Centers that prepared 5000 or more antineoplastic per year had higher concentrations of cyclophosphamide and gemcitabine on their surfaces (p = 0.0001). Almost half maintained a hazardous drugs committee (46/119, 39%), but this did not influence the cyclophosphamide contamination (p = 0.051). Hazardous drugs training was more frequent for oncology pharmacy and nursing staff than for hygiene and sanitation staff. Conclusions: This monitoring program allowed centers to benchmark their contamination with pragmatic contamination thresholds derived from the Canadian 90th percentiles. Regular participation and local hazardous drug committee involvement provide an opportunity to review practices, identify risk areas, and refresh training. [ABSTRACT FROM AUTHOR]

Due to their omnipresence in consumer products, there is a growing concern about the potential effects of nanoparticles on human health. Toxicological assessment and NP end-product studies require proper quantification of these materials in biological fluids. However, their quantifications in these media require stable predispersed NP solutions in aqueous media to enable the fortification in the matrices of interest or the preparation of calibration standards. In this study, a sample preparation scheme was developed by studying various dispersion media (polyvinylpyrrolidone and polyethylene glycol) and sonication strategies (bath and ultrasonic probe) to ensure homogeneous dispersion of titanium dioxide nanoparticles. Optimization of the various parameters was performed using SRM NIST 1898 NP reference material, composed of rutile and anatase phases. Number-based size distribution for titanium dioxide NPs was determined by dynamic light scattering and single-particle inductively coupled plasma mass spectrometry to evaluate the procedure efficiency. Changes in mean size and most frequent size distribution were also studied to determine if the agglomeration of nanoparticles occurs at the various dispersion conditions tested. Among the different dispersion parameters tested herein, the use of polyvinylpyrrolidone combined with a sonication process generated by a probe leads to a significant improvement in terms of suspension efficiency and stability over 72 h. The dispersion efficiency of the proposed methodology was assessed by single-particle inductively coupled plasma mass spectrometry with spiked biological fluids such as urine and blood. [ABSTRACT FROM AUTHOR]

In Nunavik (Northern Quebec, Canada), some mining projects are envisioned, that could increase the contamination of the environment by various chemicals, including rare earth elements (REEs), and implicitly Inuit population exposure. The objective of this study was to determine the baseline biological exposure of the population to these elements, before the potential mining development occurs. In the framework of the 2017 Qanuilirpitaa ? Inuit health survey, urine samples were obtained from a representative sample of the adult Nunavik population, which were used to constitute 30 pooled samples according to age, sex and Nunavik subregions. Pooled samples were analyzed using sensitive and accurate methods involving ICP-MS platforms to quantify urinary concentrations of 17 REEs and 7 elements of interest in Nunavik (arsenic, antimony, chromium, cobalt, nickel, thallium and uranium). REEs were mostly not detected in pooled samples from this population. Detectable concentrations were found in some samples for cerium (range: 0.5–0.7 nmol/L; 27% > method detection limit (MDL) and lanthanum (range: 0.2–0.4 nmol/L; 33% > MDL). As for the other elements of interest, antimony, arsenic, cobalt and thallium were detected in 100% of the samples, whereas chromium and nickel were detected in 83% and 80% of the samples, respectively. Concentrations of arsenic (geometric mean (GM) = 0.5 μmol/L) and cobalt (GM = 5.2 nmol/L) were greater than in the general Canadian population; the opposite was observed for nickel (GM = 8.9 nmol/L). Arsenic concentrations increased significantly with age, whereas the opposite trend was observed for nickel and thallium. In this first biomonitoring study focusing on REEs and carried out in a representative sample of the Nunavik population, we found no evidence of significant exposure from pooled samples analysis. These results could eventually be used as baseline values in future studies aiming to assess temporal trends of exposure to REEs. • Urine samples from the Inuit population of Nunavik were pooled according to subregion, sex and age. • Rare earth elements were measured using our newly-developed ICP-MS/MS method. • Cerium and lanthanum were detected in ≈30% of the pooled samples, mostly from the Ungava Bay region. • As, Co, Cr, Ni, Sb and Tl were measured in most pooled samples (≥80%). [ABSTRACT FROM AUTHOR]

The increasing use of titanium dioxide nanoparticles in daily use consumer products such as cosmetics, personal care products, food additives, and even medicine has led to growing concerns regarding human safety. It would be ideal to track exposure to this emerging nanopollutant, for example through bioassays, however, so far nanoparticle assessment in biological matrices such as urine remains challenging. The lack of data is mainly due to the limitations of the current metrology, but also to the low expected concentration in human samples. In this study, a quantification method for titanium dioxide nanoparticles in urine has been developed and validated following the ISO/CEI 17025:2017 guidelines. The detection limit for titanium dioxide nanoparticle mass concentration by single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS) was 0.05 ng mL−1. The particle size limit was determined using three different approaches, with the highest calculated limit value approaching 50 nm. Repeatability and reproducibility of 14% and 18% respectively were achieved for particle mass concentration, and 6% for both parameters for particle size determination. Method trueness and recovery were 98% and 84%, respectively. [ABSTRACT FROM AUTHOR]

Introduction: Occupational exposure to antineoplastic drugs can lead to long-term adverse effects on workers' health. Environmental monitoring is conducted once a year, as part of a Canadian monitoring program. The objective was to describe contamination with 11 antineoplastic drugs measured on surfaces. Methods: Six standardized sites in oncology pharmacy and six in outpatient clinic were sampled in each hospital. Samples were analyzed by ultra-performance liquid chromatography coupled with tandem mass spectrometry (non-platinum drugs) and by inductively coupled plasma mass spectrometry (platinum-based drugs). The limits of detection (in ng/cm2) were: 0.0006 for cyclophosphamide; 0.001 for docetaxel; 0.04 for 5-fluorouracil; 0.0004 for gemcitabine; 0.0007 for irinotecan; 0.0009 for methotrexate; 0.004 for paclitaxel, 0.009 for vinorelbine, 0.02 for doxorubicine, 0.0037 for etoposide and 0.004 for the platinum. Sub-analyses were done with a Kolmogorov-Smirnov test Results: 122 Canadian hospitals participated. Cyclophosphamide (451/1412, 32% of positive samples, 90th percentile of concentration 0.0160 ng/cm2) and gemcitabine (320/1412, 23%, 0.0036 ng/cm2) were most frequently measured on surfaces. The surfaces most frequently contaminated with at least one drug were the front grille inside the biological safety cabinet (97/121, 80%) and the armrest of patient treatment chair (92/118, 78%).The distribution of cyclophosphamide concentration was higher for centers that prepared ≥ 5000 antineoplastic drug preparations/year (p < 0.0001). Conclusions: This monitoring program allowed centers to benchmark their contamination with pragmatic contamination thresholds derived from the Canadian 90th percentiles. Problematic areas need corrective measures such as decontamination. The program helps to increase the workers' awareness. [ABSTRACT FROM AUTHOR]

The cardiotoxicity of prenatal exposure to mercury has been suggested in populations having regular contaminated seafood intake, though replications in the literature are inconsistent. The Timoun Mother-Child Cohort Study was set up in Guadeloupe, an island in the Caribbean Sea where seafood consumption is regular. At seven years of age, 592 children underwent a medical examination, including cardiac function assessment. Blood pressure (BP) was taken using an automated blood pressure monitor, heart rate variability (HRV, 9 parameters) and electrocardiogram (ECG) characteristics (QT, T-wave parameters) were measured using Holter cardiac monitoring during the examination. Total mercury concentrations were measured in cord blood at birth (median = 6.6 μg/L, N = 399) and in the children's blood at age 7 (median = 1.7 μg/L, N = 310). Adjusted linear and non-linear modelling was used to study the association of each cardiac parameter with prenatal and childhood exposures. Sensitivity analyses included co-exposures to lead and cadmium, adjustment for maternal seafood consumption, selenium and polyunsaturated fatty acids (n3-PUFAs), and for sporting activity. Higher prenatal mercury was associated with higher systolic BP at 7 years of age (β log2 = 1.02; 95% Confidence Interval (CI) = 0.10, 1.19). In boys, intermediate prenatal exposure was associated with reduced overall HRV and parasympathetic activity, and longer QT was observed with increasing prenatal mercury (β log2 = 4.02; CI = 0.48, 7.56). In girls, HRV tended to increase linearly with prenatal exposure, and no association was observed with QT-wave related parameters. Mercury exposure at 7 years was associated with decreased BP in girls (β log2 = −1.13; CI = −2.22, −0.004 for diastolic BP). In boys, the low/high-frequency (LF/HF) ratio increased for intermediate levels of exposure. Our study suggests sex-specific and non-monotonic modifications in some cardiac health parameters following prenatal exposure to mercury in pre-pubertal children from an insular fish-consuming population. • Insular populations in the French Caribbeans are exposed to mercury from high seafood consumption. • Resulting prenatal exposure may impair the development of the cardiac function. • Reduced heart rate variability and longer QT were observed in boys with higher prenatal mercury exposure. • Higher blood pressure at age 7 was observed after higher prenatal mercury exposure. [ABSTRACT FROM AUTHOR]

Arsenic is a common environmental contaminant from both naturally-occurring and anthropomorphic sources and human exposure can be detected in various tissues. Its toxicity depends on many factors including the chemical form, valence state, bioavailability, metabolism and detoxification within the human body. Of paramount concern, particularly with respect to health effects in children, is the timing of exposure as the prenatal and early life periods are more susceptible to toxic effects. The Maternal-Infant Research on Environmental Chemicals (MIREC) cohort was established to obtain national-level biomonitoring data for approximately 2,000 pregnant women and their infants between 2008 and 2011 from 10 Canadian cities. We measured total arsenic (As) in 1st and 3rd trimester maternal blood, umbilical cord blood, and infant meconium and speciated arsenic in 1st trimester maternal urine. Most pregnant women had detectable levels of total arsenic in blood (92.5% and 87.3%, respectively, for 1st and 3rd trimester); median difference between 1st and 3rd trimester was 0.1124 µg/L (p<0.0001), but paired samples were moderately correlated (Spearman r=0.41, p<0.0001). Most samples were below the LOD for umbilical cord blood (50.9%) and meconium (93.9%). In 1st trimester urine samples, a high percentage (>50%) of arsenic species (arsenous acid (As-III), arsenic acid (As-V), monomethylarsonic acid (MMA), and arsenobetaine (AsB)) were also below the limit of detection, except dimethylarsinic acid (DMA). DMA (>85% detected) ranged from

Given the susceptibility of the fetus to toxicants, it is important to estimate their exposure. Approximately 2000 pregnant women were recruited in 2008–2011 from 10 cities across Canada. Cd, Pb, Mn and total Hg were measured in maternal blood from the 1st and 3rd trimesters, umbilical cord blood, and infant meconium. Nutrient intakes of vitamin D, iron, and calcium (Ca) were assessed using a food frequency questionnaire and a dietary supplement questionnaire. Median concentrations in 1st trimester maternal blood (n = 1938) were 0.20, 8.79 and 0.70 μg/L for Cd, Mn and Hg, respectively, and 0.60 μg/dL for Pb. While the median difference between the paired 1st and 3rd trimester concentrations of Cd was 0, there was a significant decrease in Pb (0.04 μg/dL) and Hg (0.12 μg/L) and an increase in Mn (3.30 μg/L) concentrations over the course of the pregnancy. While Cd was rarely detected in cord blood (19%) or meconium (3%), median Pb (0.77 μg/dL), Mn (31.87 μg/L) and Hg (0.80 μg/L) concentrations in cord blood were significantly higher than in maternal blood. Significant negative associations were observed between estimated Ca intake and maternal Cd, Pb, Mn and Hg, as well as cord blood Pb. Vitamin D intake was associated with lower maternal Cd, Pb, and Mn as well as Pb in cord blood. Even at current metal exposure levels, increasing dietary Ca and vitamin D intake during pregnancy may be associated with lower maternal blood Pb and Cd concentrations and lower Pb in cord blood. [ABSTRACT FROM AUTHOR]

Biomonitoring for manganese (Mn) exposure is important due to its potential to cause adverse health effects. In this study, we investigate how different sample preparation methods (dilution, digestion), calibration protocols (aqueous, blood-based, standard additions), and instrumental techniques affect Mn method bias and analytical imprecision. The techniques used included graphite furnace atomic absorption spectrometry (GFAAS), dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS), and sector field (SF-) ICP-MS. We analyzed NIST SRM 1643e Trace Elements in Water and SRM 1598a Inorganic Constituents in Animal Serum (both certified for Mn), and SRM 955c Toxic Metals in Caprine Blood – Level 1 (not certified for Mn). Various matrix effects in ICP-MS produced inaccurate results for SRM 1643e and discrepant results for SRM 955c. In the absence of a certified value for Mn in SRM 955c, we assigned a “consensus” value by combining data from the New York State Department of Health (NYS), the Centers for Disease Control and Prevention (CDC) and the Centre de toxicologie du Québec (CTQ). With this interlaboratory approach, we established an “all-lab” consensus value of 16.3 ± 0.8 μg L−1 based on data from DRC-ICP-MS with dilution sample preparation and blood-based calibration. We also assigned an “all-method” consensus value of 16.3 ± 0.9 μg L−1 based on GFAAS and SF-ICP-MS data from the NYS lab and the DRC-ICP-MS all-lab consensus value. Although the expanded uncertainty (U) calculated for the consensus values may not fully account for all sources of uncertainty, it does show the relative variation that might be expected from one study to the next for the determination of Mn in blood. [ABSTRACT FROM AUTHOR]

Abstract: We review the state-of-the-art application of nanoparticles (NPs) in electrochemical analysis of environmental pollutants. We summarize methods for preparing NPs and modifying electrode surfaces with NPs. We describe several examples of applications in environmental electrochemical sensors and performance in terms of sensitivity and selectivity for both metal and metal-oxide NPs. We present recent trends in the beneficial use of NPs in constructing electrochemical sensors for environmental monitoring and discuss future challenges. NPs have promising potential to increase competitiveness of electrochemical sensors in environmental monitoring, though research has focused mainly on development of methodology for fabricating new sensors, and the number of studies for optimizing the performance of sensors and the applicability to real samples is still limited. [Copyright &y& Elsevier]

Abstract: A mathematical model of the electrocatalytic hydrogenation of phenol on a Pd/Al2O3 (10%, w/w) catalyst is developed and presented from the chemical kinetic to the fluid mechanical point of view in a laboratory scale cell. The model includes the heterogenous electrochemical steps at the microscopic scale, integrated in a full transient, three-dimensional representation of the fluid mechanics and species concentration in the electrochemical cell. In this reactor, the catalytic particles are dispersed and recirculated in the solution. The brief contact of the powder with a porous reticulated vitreous carbon is sufficient to obtain adsorbed hydrogen on the nanoaggregates who contains the phenol adsorbed. The isotherm of Langmuir and the pseudo-second-order model, based on assumption of second-order mechanism are developed. The aim of this work is to understand and validate the pseudo-second-order adsorption model when used with hydrogen adsorption isotherm, and to develop a full model of the electrochemical cell. The proposed model could be used to improve the design of industrial scale reactors. The model is validated using experimental results from [A. Bannari, C. Cirtiu, F. Kerdouss, P. Proulx, H. Ménard, Chem. Eng. Process. 45 (2006) 471]. [Copyright &y& Elsevier]