Anthropogenic lead pervasive in Canadian Arctic seawater.

Anthropogenic Pb is widespread in the environment including remote places. However, its presence in Canadian Arctic seawater is thought to be negligible based on low dissolved Pb (dPb) concentrations and proxy data. Here, we measured dPb isotopes in Arctic seawater with very low dPb concentrations (average ∼5 pmol ⋅ kg-1) and show that anthropogenic Pb is pervasive and often dominant in the western Arctic Ocean. Pb isotopes further reveal that historic aerosol Pb from Europe and Russia (Eurasia) deposited to the Arctic during the 20th century, and subsequently remobilized, is a significant source of dPb, particularly in water layers with relatively higher dPb concentrations (up to 16 pmol ⋅ kg-1). The 20th century Eurasian Pb is present predominantly in the upper 1,000 m near the shelf but is also detected in older deep water (2,000 to 2,500 m). These findings highlight the importance of the remobilization of anthropogenic Pb associated with previously deposited aerosols, especially those that were emitted during the peak of Pb emissions in the 20th century. This remobilization might be further enhanced because of accelerated melting of permafrost and ice along with increased coastal erosion in the Arctic. Additionally, the detection of 20th century Eurasian Pb in deep water helps constrain ventilation ages. Overall, this study shows that Pb isotopes in Arctic seawater are useful as a gauge of changing particulate and contaminant sources, such as those resulting from increased remobilization (e.g., coastal erosion) and potentially also those associated with increased human activities (e.g., mining and shipping).

Initial assessment of multi-compound antineoplastic drug surface contamination in Argentinean healthcare centers: Insights into occupational exposures in South America.

INTRODUCTION: Antineoplastic drug contamination can result in severe health effects for healthcare workers exposed to them. Despite the worldwide growing concern regarding these drugs and sustained monitoring efforts in developed countries, there is almost no data about surface contamination levels in Argentina, in particular, and South America, in general. METHODS: Antineoplastic drug contamination was measured in three Argentinean public hospitals (pharmacy and daycare center areas) by surface wiping and liquid chromatography coupled with tandem mass spectrometry. RESULTS AND DISCUSSION: Eleven drugs were detected, in 51 of 58 sampled surfaces, in variable concentrations from 0.00064 to 7.3 ng cm-2, with cyclophosphamide, gemcitabine, and paclitaxel as the most prevalent drugs. This highly variable antineoplastic distribution reflects differences in facility layout, number of patients, antineoplastic drug use, etc., at each hospital. Values exceeding the 1 ng cm-2 threshold were detected in 13 surfaces of the two hospitals handling the largest amounts of antineoplastic drugs. The cyclophosphamide 75th percentile averaged 0.030 ng cm-2 comparable to the high values reported more than 10 years ago for developed countries, emphasizing the potential of reducing antineoplastic contamination by implementing routine monitoring and improved cleaning and handling procedures. CONCLUSION: This study is the first survey of multi-compound surface antineoplastic contamination in Argentinean (and South American) hospitals, providing a baseline against which future studies can be compared. Widespread antineoplastic contamination has been detected on numerous surfaces, with concentrations surpassing suggested threshold exposure levels (1 ng cm-1) for some surfaces in two of the sampled hospitals.

Alterations in the sterol signature of detritivorous fish along pollution gradients in the Río de la Plata basin (Argentina): From plant to sewage-based diet.

In order to assess the impact of sewage pollution on the diet of the strict detritivorous and migratory South American fish, Prochilodus lineatus, 16 sterol biomarkers were analyzed by gas chromatography-mass spectrometry from fish muscle (n: 144) collected along 1200 km in the Rio de la Plata basin. Sterol concentrations were fairly homogeneous (2.4 ± 1.3 mg g-1 dry weight), but their proportion in lipids was highly variable and inversely related to both body mass and lipid contents, reflecting the more conservative character of sterols compared to the rapid accumulation of fat as fish grows. As expected, the muscle sterol signature was widely dominated by cholesterol (92 ± 4.5% of total sterols), but it exhibited a remarkable diversity with variable proportions of fecal coprostanol (4.0 ± 4.4%) and plant sterols (3.1 ± 1.9%, e.g. sitosterol and campesterol). Muscle sterols exhibited contrasting geographical differences associated with dietary shifts from plant-derived detritus in the northern reaches of the basin (N: Paraná and Uruguay Rivers), to sewage dominated inputs at Buenos Aires (BA). Fish from BA are fattier (lipids: 35 ± 18 vs. 15 ± 9.0% at N), with higher total sterol contents (2.6 ± 1.3 vs. 1.9 ± 1.0 mg g-1), abundant coprostanol (5.3 ± 4.4 vs. 0.46 ± 1.1%) and lower plant sterols (2.6 ± 1.6 vs 4.6 ± 2.0%), reflecting a diet shifted to anthropogenic organic matter as opposed to vegetal detritus in the north. Accordingly, BA fish presented lower phyto/fecal sterol ratios (0.37 ± 0.21 vs. 0.91 ± 0.12 at N) and higher copro/epicoprostanol ratios (0.95 ± 0.082 vs 0.51 ± 0.25 at N), indicating fresh fecal inputs which provide a valuable supply of easily absorbed organic matter at this site. In addition, the sterol signature allowed to distinguish migratory fish from BA collected 900 km north (previously identified by their pollutant fingerprint and biochemical composition). In fact, coprostanol concentrations show a direct relationship with human populations along the basin, highlighting the usefulness of fecal sterol biomarkers as tracers of polluted fish stocks.

The application of novel field measurement and field evaluation protocols for assessing health care workers' exposure risk to antineoplastic drugs.

Contamination of multiple antineoplastic drugs (ADs) on work surfaces presents an exposure concern for health care workers. Surface wipe sampling is a recognized method to evaluate the degree of contamination present. Our research team has previously reported on wipe sampling and analytical methods to simultaneously detect 10 commonly used ADs from a single wipe. Our objectives here were: to field test a protocol consisting of the wipe sampling method and an accompanying wipe sample collection tool kit and confirm this protocol can be effectively used by health care workers to assess drug contamination levels in their facilities; and, to confirm the potential for simultaneous exposure to multiple antineoplastic drugs. Three facilities within one health authority in British Columbia, Canada participated in this field study. In collaboration with the site health and safety advisors, up to 25 surfaces within each facility were considered for sampling. Collected wipe samples were analyzed using HPLC-MS/MS to quantify the 10 analyte, resulting in 750 potential analyses. Following the sampling, each of the three facilities' safety advisors provided feedback regarding the usability of the protocols. Among the 72 wipe samples actually collected (or 720 analyses conducted), detectable levels and simultaneous contamination of work surfaces of five of the 10 analytes were found at all three participating sites: 5-fluorouracil, cyclophosphamide, vincristine, paclitaxel, and methotrexate; (range < LoD to 33.0 ng/cm2) with 5-fluorouracil having the highest concentration in every instance. Drug contamination was found on a variety of different work surfaces in pharmacies and patient care areas among all three sites. Users of the sampling protocols were generally satisfied with the wipe sample collection toolkit with some minor suggestions for improvement. Our findings support the hypothesis that health care workers may be simultaneously at risk of exposure to several ADs. Our toolkit was found to be user-friendly and manageable by those who were not experienced in collecting wipe samples to monitor contamination of ADs on the work surfaces in their facilities.

Removal and Re-use of Tar-contaminated Sediment by Freeze-dredging at a Coking Plant Luleå, Sweden.

Submerged tar-contaminated sediment are generally very loose, which makes remediation challenging. We tested if a modified version of freeze-dredging could be used to remove and dewater such sediment in a canal down-stream a coking plant. PVC hoses carrying a heat medium were placed horizontally in the submerged sediment. Five days of freezing allowed straightforward removal of most of the sediment. Flat freeze cells were placed side by side in the canal to remove the rest. The freeze-thaw process increased the dry substance content from approximately 50 to 80%. Outdoors storage under rainy conditions did not re-wet the dried sediment. The material was successfully used as feed-stock in the coking plant, with the double cost-benefit of avoided transportation to deposit and reduced use of coal. The study demonstrates that freeze-dredging can facilitate removal, storage and beneficial re-use of submerged tar-contaminated sediment.

A surface wipe sampling and LC-MS/MS method for the simultaneous detection of six antineoplastic drugs commonly handled by healthcare workers.

An effective wipe sampling and LC-MS/MS method was developed to simultaneously analyze six commonly administered antineoplastic drugs in stainless steel surface. The analyzed drugs were methotrexate, paclitaxel, cyclophosphamide, 5-fluorouracil, vincristine, and oxaliplatin, a frequently prepared antineoplastic drug that has not been included among any of the published simultaneous detection methods. The established method was used to evaluate the recoveries of antineoplastic drugs on brand new and worn stainless steel surfaces by wiping the plates with a Whatman filter paper wetted with 0.5 mL of water/methanol (20:80) with 0.1% formic acid followed by LC-MS/MS before desorbing the filter with a water/methanol (50:50) solution. A significant decrease in the recovery of all evaluated drugs was found when worn plates were used. Additionally, the inter-personnel variability on drug recoveries during wiping procedures was evaluated. Significantly higher recoveries were achieved by the personnel with more training and experience versus personnel without prior experience. Finally, a laboratory stability test was developed to assess the degradation of the antineoplastic drugs during replicated shipping conditions. With the exception of vincristine sulfate which exhibited a significant (p < 0.05) degradation after 48 h, all evaluated drugs were stable during the first 24-48 h. However, after 144 h, an increase in the degradation of all evaluated drugs was observed, with oxaliplatin and 5-fluorouracil exhibiting the most degradation.

Wipe Sampling Method and Evaluation of Environmental Variables for Assessing Surface Contamination of 10 Antineoplastic Drugs by Liquid Chromatography/Tandem Mass Spectrometry.

This paper describes a novel wipe sampling and high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) method capable of simultaneously detecting 10 antineoplastic drugs (5-fluorouracil, oxaliplatin, methotrexate, vindesine, ifosfamide, cyclophosphamide, vincristine, vinblastine, docetaxel, and paclitaxel). The good overall recoveries and sensitivity values of this method along with the comparatively short run time (8 min) allows for its use in routine monitoring in health care facilities. The long-term behavior of the studied drugs on contaminated surfaces and the effect of surface roughness on drug recoveries were studied to gain insights about how these environmental variables influence the detection, cleaning, and occupational exposure of these drugs. Surfaces with higher roughness parameter (Ra) values (rougher) had the lowest recoveries while those with lower Ra (smoother) presented the highest recoveries. Long-term assessments evidence distinctive drug behaviors with oxaliplatin, vindesine, vincristine, and vinblastine being the less persistent drugs (~20% was recovered after 24 h) and docetaxel and paclitaxel the most persistent drugs with recoveries of 40% and 80% after 1 month. This information indicates the importance of collecting ancillary information about drug usage (throughput, timing, cleaning procedures, etc.) to interpret the results in the context of potential exposure. Finally, the method was successfully applied to evaluate trace surface contamination down to the single picogram per square centimeter in multiple work areas within three local health care centers on Vancouver Island, Canada.