Publications by authors named "Niladri Basu"

182 Publications

Personal exposure to particulate matter and heart rate variability among informal electronic waste workers at Agbogbloshie: a longitudinal study.

BMC Public Health 2021 Nov 25;21(1):2161. Epub 2021 Nov 25.

Department of Biological, Environmental & Occupational Health Sciences, School of Public Health, University of Ghana, P.O. Box LG13, Accra, Ghana.

Background: Informal electronic waste recycling activities are major contributors to ambient air pollution, yet studies assessing the effects or relationship between direct/continuous exposure of informal e-waste workers to particulate matter and cardiovascular function are rare.

Methods: Repeated measurements of fractions of PM, PM, and PM in personal air of informal e-waste workers, (n = 142) and a comparable group (n = 65) were taken over a period of 20 months (March 2017 to November, 2018). Concurrently, 5-min resting electrocardiogram was performed on each participant to assess resting heart rate variability indices. Linear mixed-effects models were used to assess the association between PM fractions and cardiac function.

Results: SDNN, RMSSD, LF, HF and LH/HF ratio were all associated with PM. Significant associations were observed for PM and Mean NN (p = 0.039), PM10 and SDNN (p = 0.035) and PM 10-2.5 and LH/HF (p = 0.039). A 10 μg/m increase in the concentrations of PM , PM, and PM in personal air was associated with reduced HRV indices and increased resting HR. A 10 μg/m per interquartile (IQR) increase in PM and PM, decreased SDNN by 11% [(95% CI: - 0.002- 0.000); (p = 0.187)] and 34% [(95% CI: - 0.002-0.001); (p = 0.035)] respectively. However, PM increased SDNN by 34% (95% CI: - 1.32-0.64); (p = 0.493). Also, 10 μg/m increase in PM, PM and PM decreased RMSSD by 27% [(- 1.34-0.79); (p = 0.620)], 11% [(- 1.73, 0.95); (p = 0.846)] and 0.57% [(- 1.56-0.46); (p = 0.255%)].

Conclusion: Informal e-waste workers are at increased risk of developing cardiovascular disease from cardiac autonomic dysfunction as seen in reduced HRV and increased heart rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12889-021-12241-2DOI Listing
November 2021

Metal Exposures, Noise Exposures, and Audiometry from E-Waste Workers in Agbogbloshie, Ghana.

Int J Environ Res Public Health 2021 09 13;18(18). Epub 2021 Sep 13.

Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI 48109-2029, USA.

Metals, such as lead, may be ototoxic, but this property is not well understood, especially in conjunction with noise. This cross-sectional study investigated hearing, noise, and metal biomarkers in informal electronic waste (e-waste) recycling workers in Accra, Ghana. Workers (N = 58) participated in audiometric testing, a survey, blood collection, and personal noise dosimetry. Sixty percent of participants displayed audiometric notches indicative of noise-induced hearing loss (NIHL). Most workers (86%) reported high noise while working. Daily average noise levels were in the range 74.4-90.0 dBA. Linear regression models indicated participants who lived at Agbogbloshie Market for longer periods were significantly associated with worse hearing thresholds at 4 and 6 kHz. The models did not identify blood levels of lead, mercury, or cadmium as significant predictors of worse hearing thresholds or larger noise notches, but increased levels of selenium were significantly associated with better hearing at 6 kHz. Models of thresholds at 4 and 6 kHz were improved by including an interaction term between the maximum noise exposure and the level of zinc in whole blood, suggesting that zinc may protect hearing at lower noise levels, but not at higher levels. Further study of the relationships between elements, noise, and NIHL is needed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph18189639DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8470926PMC
September 2021

International Consortium to Advance Cross-Species Extrapolation of the Effects of Chemicals in Regulatory Toxicology.

Environ Toxicol Chem 2021 Dec 25;40(12):3226-3233. Epub 2021 Oct 25.

Safety and Environmental Assurance Centre, Unilever, Sharnbrook, Bedfordshire, UK.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.5214DOI Listing
December 2021

Comparison and Agreement of Toxic and Essential Elements Between Venous and Capillary Whole Blood.

Biol Trace Elem Res 2021 Sep 21. Epub 2021 Sep 21.

Faculty of Agricultural and Environmental Sciences, McGill University, Ste-Anne-de-Bellevue, Montreal, Québec, Canada.

For practical and ethical reasons, there is an interest in the use of capillary blood as an alternative to classical human biomonitoring methods that use venipuncture. However, with the exception of Pb, few elements have been studied in detail to understand potential differences in measures between capillary and venous blood. To increase our understanding of the agreement in concentrations of select toxic metal(loid)s and essential minerals in venous and capillary whole blood. Concentrations of As, Pb, Cd, Mn, Cu, Fe, and Se were measured with Inductively Coupled Plasma-Mass Spectrometry in venous and capillary whole blood samples obtained from 49 healthy adult members of the McGill University community in 2016. Measured concentrations of all elements were similar to values reported in background populations. There were strong correlations (i.e., p < 0.001) in measures taken for all these elements between capillary and venous blood. Using Bland-Altman, a deeper investigation of the agreement between the measures found relatively good agreement for blood As, Pb, Cu, and Fe. For blood Cd, Mn, and Se, the agreement between the measures taken in capillary and venous blood was less consistent, though more research is needed to determine if the method can be improved and/or if there are real differences. For the seven elements under investigation, there was relatively good correlation and agreement in measures taken between capillary and venous blood from the same individual. Further research is needed to confirm these findings (particularly from more diverse population groups), expand the number of elements analyzed, and explore the utility of capillary sampling in biomonitoring programs that take samples using traditional venipuncture methods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12011-021-02931-8DOI Listing
September 2021

Effects of Electronic and Electrical Waste-Contaminated Soils on Growth and Reproduction of Earthworm (Alma nilotica).

Environ Toxicol Chem 2021 Aug 25. Epub 2021 Aug 25.

Department of Natural Resource Sciences, Faculty of Agricultural and Environmental Sciences, McGill University, Quebec City, Quebec, Canada.

Informal recycling of electronic waste (e-waste) contaminates local environments with metals and other organic compounds. The adverse effects on native earthworm populations are poorly understood. The objective of the present study was to determine metal concentrations in soils from e-waste activity sites in Douala (Cameroon) and assess the effects of these soils on the growth and reproduction of the local earthworm, Alma nilotica. Concentrations of nine metals (arsenic [As], cadmium [Cd], cobalt [Co], chromium [Cr], copper [Cu], mercury [Hg], nickel [Ni], lead [Pb], and zinc [Zn]) were measured in soil samples collected from eight e-waste activity and two non-e-waste sites. Earthworms were then exposed to these soils in the laboratory following test guidelines of the Organisation for Economic Co-operation and Development. Metal concentrations in the e-waste-contaminated soils were significantly higher than in the non-e-waste soils. The e-waste soils were found to have a different soil metal profile (Cu > Pb > Zn > Cr > Ni > Co > As > Cd > Hg) from that of the non-e-waste soils (Zn > Cr > Cu > Pb > Ni > As > Cd > Co > Hg). Earthworm growth and reproduction were significantly inhibited in organisms exposed to soils from e-waste sites. Reproduction was particularly affected, with a mean of 8 ± 5.6 offspring/10 worms in the e-waste-exposed worm groups compared with 90.5 ± 0.7 in non-e-waste soil worms. Notably, earthworm growth recovered during depuration in clean soil, indicating the possibility of remediation activities. The results demonstrate that soils at e-waste sites can affect the health of resident worm populations, which may be more sensitive than temperate species. They also highlight the potential of a bioassay-based approach in monitoring risks at e-waste sites. Environ Toxicol Chem 2021;00:1-11. © 2021 SETAC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.5198DOI Listing
August 2021

Work-Related Exposures and Musculoskeletal Disorder Symptoms among Informal E-Waste Recyclers at Agbogbloshie, Ghana.

Proc Congr Int Ergon Assoc (2021) 2021 8;222:677-681. Epub 2021 May 8.

Department of Biological, Environmental & Occupational Health Sciences, School of Public Health, University of Ghana; P.O. Box LG13, Accra, Ghana.

Recycling of electrical and electronic waste (e-waste) in developing countries is mostly conducted in the informal sector consisting of low skilled workers. Informal e-waste recycling predominantly involves the physically demanding work of manually collecting, dismantling and burning of e-waste items to extract reusable components and valuable metals including gold or copper. This cross-sectional study investigated the effects of manual e-waste recycling work on the musculoskeletal health of 176 workers at Agbogbloshie in Accra, Ghana - the largest informal e-waste dumpsites in Africa. Findings indicate significant associations between prolonged walking and weighted MSD symptom scores for the lower extremities, and between manual material handlings tasks and weighted MSD symptom scores for the upper extremities and lower back. The study calls attention to the need for ergonomics research in the informal work sector to promote safer practices and address a range of worker health concerns.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/978-3-030-74611-7_93DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8301232PMC
May 2021

Using Transcriptomics and Metabolomics to Understand Species Differences in Sensitivity to Chlorpyrifos in Japanese Quail and Double-Crested Cormorant Embryos.

Environ Toxicol Chem 2021 Nov 15;40(11):3019-3033. Epub 2021 Sep 15.

Ecotoxicology and Wildlife Health Division, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, Ontario, Canada.

Modern 21st-century toxicity testing makes use of omics technologies to address critical questions in toxicology and chemical management. Of interest are questions relating to chemical mechanisms of toxicity, differences in species sensitivity, and translation of molecular effects to observable apical endpoints. Our study addressed these questions by comparing apical outcomes and multiple omics responses in early-life stage exposure studies with Japanese quail (Coturnix japonica) and double-crested cormorant (Phalacrocorax auritus), representing a model and ecological species, respectively. Specifically, we investigated the dose-dependent response of apical outcomes as well as transcriptomics and metabolomics in the liver of each species exposed to chlorpyrifos, a widely used organophosphate pesticide. Our results revealed a clear pattern of dose-dependent disruption of gene expression and metabolic profiles in Japanese quail but not double-crested cormorant at similar chlorpyrifos exposure concentrations. The difference in sensitivity between species was likely due to higher metabolic transformation of chlorpyrifos in Japanese quail compared to double-crested cormorant. The most impacted biological pathways after chlorpyrifos exposure in Japanese quail included hepatic metabolism, oxidative stress, endocrine disruption (steroid and nonsteroid hormones), and metabolic disease (lipid and fatty acid metabolism). Importantly, we show consistent responses across biological scales, suggesting that significant disruption at the level of gene expression and metabolite profiles leads to observable apical responses at the organism level. Our study demonstrates the utility of evaluating effects at multiple biological levels of organization to understand how modern toxicity testing relates to outcomes of regulatory relevance, while also highlighting important, yet poorly understood, species differences in sensitivity to chemical exposure. Environ Toxicol Chem 2021;40:3019-3033. © 2021 SETAC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.5174DOI Listing
November 2021

Assessing the Toxicity of 17α-Ethinylestradiol in Rainbow Trout Using a 4-Day Transcriptomics Benchmark Dose (BMD) Embryo Assay.

Environ Sci Technol 2021 08 22;55(15):10608-10618. Epub 2021 Jul 22.

Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B3.

There is an urgent demand for more efficient and ethical approaches in ecological risk assessment. Using 17α-ethinylestradiol (EE2) as a model compound, this study established an embryo benchmark dose (BMD) assay for rainbow trout (RBT; ) to derive transcriptomic points-of-departure (tPODs) as an alternative to live-animal tests. Embryos were exposed to graded concentrations of EE2 (measured: 0, 1.13, 1.57, 6.22, 16.3, 55.1, and 169 ng/L) from hatch to 4 and up to 60 days post-hatch (dph) to assess molecular and apical responses, respectively. Whole proteome analyses of alevins did not show clear estrogenic effects. In contrast, transcriptomics revealed responses that were in agreement with apical effects, including excessive accumulation of intravascular and hepatic proteinaceous fluid and significant increases in mortality at 55.1 and 169 ng/L EE2 at later time points. Transcriptomic BMD analysis estimated the median of the 20th lowest geneBMD to be 0.18 ng/L, the most sensitive tPOD. Other estimates (0.78, 3.64, and 1.63 ng/L for the 10th percentile geneBMD, first peak geneBMD distribution, and median geneBMD of the most sensitive over-represented pathway, respectively) were within the same order of magnitude as empirically derived apical PODs for EE2 in the literature. This 4-day alternative RBT embryonic assay was effective in deriving tPODs that are protective of chronic effects of EE2.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.est.1c02401DOI Listing
August 2021

Registration status, mercury exposure biomarkers, and neuropsychological assessment of artisanal and small-scale gold miners (ASGM) from the Western Region of Ghana.

Environ Res 2021 10 7;201:111639. Epub 2021 Jul 7.

Department of Environmental Health Sciences, University of Michigan School of Public Health, USA; Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, Canada. Electronic address:

The artisanal and small-scale gold mining (ASGM) sector is estimated to be the largest anthropogenic source of mercury pollution worldwide, and not surprisingly human exposures in this sector are amongst the highest of all population groups. While formalization of the sector has been proposed as a solution to help improve health and safety within ASGM sites, there are few empirical studies in support of this notion. The objective of this study was to assess if individuals working in ASGM sites that are registered have reduced mercury exposures and better neuropsychological scores than workers from unregistered sites. To achieve this objective, we studied biological samples (urine, hair) and survey data from a study of 404 ASGM workers (of which, 295 worked in registered ASGM sites) conducted in Tarkwa (Ghana) in 2014. Between miners working in registered and unregistered sites, there were few differences in socio-demographic characteristics. Median urinary mercury concentration (specific gravity-corrected) among those from unregistered mines was nearly 3-fold higher than those from the registered mines (18.5 versus 6.6 μg/L), and in the overall population the median concentration was 10.0 μg/L, and ranged from 0.3 to 2499 μg/L. Mercury biomarkers varied across ASGM work categories (e.g., those who burned or amalgamated had the highest) and users of personal protective equipment. Nearly 30% of the study population indicated having some challenges concerning, for example, reduced appetite, hair loss, or excess salivation. Ataxia and rigidity of gait were absent in most of the participants, and for those with slight, moderate, or marked responses, there were no differences between miners from registered and unregistered sites, across work groups, as well as in reference to mercury biomarker measures. For the pencil tapping, Frostig, matchbox, and Wechsler tests, no striking differences were found though a correlation was found between urinary mercury levels and matchbox scores among those who amalgamate and burn, and scores were similar to past studies using the same tests in ASGM sites. We believe this is the first study to compare mercury exposures and neuropsychological test results between miners from registered and unregistered ASGM sites. In doing so, the research findings provide the necessary evidence for stakeholders and parties of the Minamata Convention considering various response options to help fulfill their obligations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2021.111639DOI Listing
October 2021

Sex- and Developmental Stage-Related Differences in the Hepatic Transcriptome of Japanese Quail (Coturnix japonica) Exposed to 17β-Trenbolone.

Environ Toxicol Chem 2021 Sep 8;40(9):2559-2570. Epub 2021 Aug 8.

US Geological Survey, Eastern Ecological Science Center, Patuxent Research Refuge, Beltsville, Maryland, USA.

Endocrine-disrupting chemicals can cause transcriptomic changes that may disrupt biological processes associated with reproductive function including metabolism, transport, and cell growth. We investigated effects from in ovo and dietary exposure to 17β-trenbolone (at 0, 1, and 10 ppm) on the Japanese quail (Coturnix japonica) hepatic transcriptome. Our objectives were to identify differentially expressed hepatic genes, assess perturbations of biological pathways, and examine sex- and developmental stage-related differences. The number of significantly differentially expressed genes was higher in embryos than in adults. Male embryos exhibited greater differential gene expression than female embryos, whereas in adults, males and females exhibited similar numbers of differentially expressed genes (>2-fold). Vitellogenin and apovitellenin-1 were up-regulated in male adults exposed to 10 ppm 17β-trenbolone, and these birds also exhibited indications of immunomodulation. Functional grouping of differentially expressed genes identified processes including metabolism and transport of biomolecules, enzyme activity, and extracellular matrix interactions. Pathway enrichment analyses identified as perturbed peroxisome proliferator-activated receptor pathway, cardiac muscle contraction, gluconeogenesis, growth factor signaling, focal adhesion, and bile acid biosynthesis. One of the primary uses of 17β-trenbolone is that of a growth promoter, and these results identify effects on mechanistic pathways related to steroidogenesis, cell proliferation, differentiation, growth, and metabolism of lipids and proteins. Environ Toxicol Chem 2021;40:2559-2570. © 2021 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.5143DOI Listing
September 2021

Global DNA (LINE-1) methylation is associated with lead exposure and certain job tasks performed by electronic waste workers.

Int Arch Occup Environ Health 2021 Nov 20;94(8):1931-1944. Epub 2021 Jun 20.

Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Legon, P.O. Box LG13, Accra, Ghana.

Objective: This study assessed the associations between blood and urine levels of toxic metals; cadmium (Cd) and lead (Pb), and methylation levels of the LINE-1 gene among e-waste and control populations in Ghana.

Methods: The study enrolled 100 male e-waste workers and 51 all-male non-e-waste workers or controls. The concentrations of Cd and Pb were measured in blood and urine using inductively coupled plasma mass spectrometry, while LINE1 methylation levels were assessed by pyrosequencing of bisulfite-converted DNA extracted from whole blood. Single and multiple metals linear regression models were used to determine the associations between metals and LINE1 DNA methylation.

Results: Blood lead (BPb) and urine lead (UPb) showed higher median concentrations among the e-waste workers than the controls (76.82 µg/L vs 40.25 µg/L, p ≤ 0.001; and 6.89 µg/L vs 3.43 µg/L, p ≤ 0.001, respectively), whereas blood cadmium (BCd) concentration was lower in the e-waste workers compared to the controls (0.59 µg/L vs 0.81 µg/L, respectively, p = 0.003). There was no significant difference in LINE1 methylation between the e-waste and controls (85.16 ± 1.32% vs 85.17 ± 1.11%, p = 0.950). In our single metal linear regression models, BPb was significantly inversely associated with LINE1 methylation in the control group (β = - 0.027, 95% CI - 0.045, - 0.010, p = 0.003). In addition, a weak association between BPb and LINE1 was observed in the multiple metals analysis in the e-waste worker group (β = - 0.005, 95% CI - 0.011, 0.000, p = 0.058).

Conclusion: Continuous Pb exposure may interfere with LINE1 methylation, leading to epigenetic alterations, thus serving as an early epigenetic marker for future adverse health outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00420-021-01733-8DOI Listing
November 2021

Variation in biomarker levels of metals, persistent organic pollutants, and omega-3 fatty acids in association with genetic polymorphisms among Inuit in Nunavik, Canada.

Environ Res 2021 09 29;200:111393. Epub 2021 May 29.

Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada. Electronic address:

Background: Biomarker measures of contaminant exposure and nutrient status can help increase understanding of the risks and benefits associated with the consumption of traditional foods by Inuit. While gene-environment and gene-nutrient interactions may help explain variations in biomarker measures, the role of genetic polymorphisms is largely understudied especially for vulnerable sub-populations.

Objective: The aim of this study was to characterize the relationship between single nucleotide polymorphisms (SNPs) in key genes and blood concentrations of environmental chemicals and nutrients among Inuit.

Methods: Blood samples from 665 individuals who participated in the Qanuippitaa Survey (Nunavik, Canada) in 2004 were analyzed for toxicants and nutrients. DNA was extracted and 140 SNPs in classes relevant to the toxicokinetics and/or toxicodynamics of the target contaminants and nutrients, and/or are involved in cardiovascular health and lipid metabolism were genotyped using the Sequenom iPLEX Gold platform.

Results: Geometric means (μg/L) of mercury (Hg), cadmium (Cd), lead (Pb), DDE, PCB-153, and selenium (Se) were 11.1, 2.8, 39.9, 2.9, 1.1 and 301.2, respectively. Red blood cell membrane levels of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were 5.1%/total fatty acid (TFA) and 1.3%/TFA respectively. Out of 106 SNPs which met our inclusion criteria, biomarker levels for Hg, Cd, Pb, DDE, PCB-153, DHA, and EPA differed (p < 0.05) by genotype for 20, 13, 12, 19, 21, 9 and 8 SNPs, respectively. Following Bonferroni correction (p < 0.0005), only 9 SNPs remained significant (rs2274976 in MTHFR, rs174602 in FADS2, rs7115739 and rs74771917 in FADS3, rs713041 in GPX4, rs2306283 and rs4149056 in SLCO1B1, rs1885301 in ABCC2/MRP2, and rs4244285 in CYP2C19; 5 associated with Hg, 2 with Pb, 2 with DDE, 4 with PCB-153, 1 with DHA).

Conclusions: The findings suggest that polymorphisms in environmentally-responsive genes can influence biomarker levels of key toxicants and nutrients. While there are no immediate clinical or public health implications of these findings, we believe that such gene-environment and gene-nutrient studies provide a foundation that will inform and provide direction to future studies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2021.111393DOI Listing
September 2021

Methylmercury Measurements in Dried Blood Spots from Electronic Waste Workers Sampled from Agbogbloshie, Ghana.

Environ Toxicol Chem 2021 Aug 1;40(8):2183-2188. Epub 2021 Jul 1.

Faculty of Agricultural and Environmental Sciences, McGill University, Ste-Anne-de-Bellevue, Québec, Canada.

Biomonitoring methylmercury (MeHg) exposure is problematic in resource-limited settings and with difficult-to-access populations where traditional biomarker approaches present logistical, economic, and ethical issues. The present study aimed to validate the use of dried blood spots (DBS) to assess MeHg exposure in a real-world contaminated field setting. Whole-blood and DBS samples were collected from electronic waste workers (n = 20) from Agbogbloshie (Ghana) in 2017, and DBS were also artificially created in the laboratory using the field-collected blood. Whole-blood MeHg concentrations averaged 0.84 µg/L, which was not different from levels measured in the corresponding DBS samples (field-collected or artificially created). Whole-blood MeHg comprised 61% of the blood total Hg concentrations. Linear regression analysis revealed no differences in MeHg concentrations between whole-blood samples and field-collected DBS (slope 0.89, R  = 0.94) and between field and laboratory DBS (slope 0.89, R  = 0.96). The MeHg content in DBS punch blanks averaged 0.86 pg and thus was not of concern. These findings indicate that DBS are a suitable tool for assessing MeHg exposure in real-world environmental settings that may be heavily contaminated.  Environ Toxicol Chem 2021;40:2183-2188. © 2021 SETAC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.5121DOI Listing
August 2021

Biomonitoring of metals in blood and urine of electronic waste (E-waste) recyclers at Agbogbloshie, Ghana.

Chemosphere 2021 Oct 27;280:130677. Epub 2021 Apr 27.

Department of Biological, Environmental & Occupational Health Sciences, School of Public Health, University of Ghana, Ghana.

There is growing evidence that e-waste recyclers may be exposed to potentially high levels of metals though associations between such exposures and specific work activities is not well established. In addition, studies have focused on metals traditionally biomonitored and there is no data on the exposure of recyclers to elements increasingly being used in new technologies. In the current study, levels of metals were measured in blood and urine of e-waste recyclers at Agbogbloshie (Ghana) and a control group. Blood and urine samples (from 100 e-waste recyclers and 51 controls) were analyzed for 17 elements (Ag, As, Ba, Cd, Ce, Cr, Eu, La, Mn, Nd, Ni, Pb, Rb, Sr, Tb, Tl, Y) using the ICP-MS. Most e-waste recyclers reported performing at least 4 different tasks in decreasing order as e-waste dismantling (54%), trading/selling of e-waste (45%), burning wires only (40%), and collecting wires after burning (34%). Mean levels of blood Pb, Sr, Tl, and urinary Pb, Eu, La, Tb, and Tl were significantly higher in recyclers versus controls. In general, the collectors and sorters tended to have higher elemental levels than other work groups. Blood Pb levels (mean 92.4 μg/L) exceeded the U.S. CDC reference level in 84% of the e-waste recyclers. Likewise, blood Cd, Mn, and urinary As levels in recyclers and controls were higher than in reference populations elsewhere. E-waste recyclers are exposed to metals traditionally studied (e.g., Pb, Cd, As) and several other technology-critical and rare earth elements which previously have not been characterized through human biomonitoring.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2021.130677DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8287752PMC
October 2021

Geolocators link marine mercury with levels in wild seabirds throughout their annual cycle: Consequences for trans-ecosystem biotransport.

Environ Pollut 2021 Sep 30;284:117035. Epub 2021 Mar 30.

Departments of Biology, Mathematics and Statistics, University of Ottawa, Ottawa, ON, K1N 6N5, Canada. Electronic address:

Seabirds are widely used as indicators of marine pollution, including mercury (Hg), because they track contaminant levels across space and time. However, many seabirds are migratory, and it is difficult to understand the timing and location of their Hg accumulation. Seabirds may obtain Hg thousands of kilometers away, during their non-breeding period, and deposit that Hg into their terrestrial breeding colonies. We predicted that Hg concentration in rectrices reflects exposure during the previous breeding season, in body feathers reflects non-breeding exposure, and in blood collected during breeding reflects exposure during current breeding. To test this hypothesis, we measured total Hg concentration in these three tissues, which reflect different timepoints during the annual cycle of rhinoceros auklets (Cerorhinca monocerata) breeding on both sides of the North Pacific (Middleton Island in Alaska and Teuri Island in Hokkaido), and tracked their wintering movement patterns with biologging devices. We (i) identify the wintering patterns of both populations, (ii) examine Hg levels in different tissues representing exposure at different time periods, (iii) test how environmental Hg exposure during the non-breeding season affects bird contamination, and (iv) assess whether variation in Hg levels during the non-breeding season influences levels accumulated in terrestrial plants. Individuals from both populations followed a figure-eight looping migration pattern. We confirm the existence of a pathway from environmental Hg to plant roots via avian tissues, as Hg concentrations were higher in plants within the auklet colonies than at control sites. Hg concentrations of breast feathers were higher in Alaskan than in Japanese auklets, but Hg concentrations in rectrices and blood were similar. Moreover, we found evidence that tissues with different turnover rates could record local anthropogenic Hg emission rates of areas visited during winter. In conclusion, Hg was transported across thousands of kilometers by seabirds and transferred to local plants.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envpol.2021.117035DOI Listing
September 2021

Spatial Distribution of Heavy Metals and Pollution of Environmental Media Around a Used Lead-acid Battery Recycling Center in Ibadan, Nigeria.

J Health Pollut 2021 Mar 2;11(29):210304. Epub 2021 Mar 2.

Department of Environmental Health Sciences, University of Michigan, Ann Arbor, USA.

Background: Heavy metals are usually present in trace amounts in various environmental media such as water, soil, and air, and many are poisonous to human health even at very low concentrations.

Objectives: To assess the risk of heavy metal contamination of water, soil, and plants around a used lead acid battery (ULAB) recycling center in Ibadan, Nigeria.

Methods: Environmental samples (water, soil, and plants) were collected using standard methods and concentrations of arsenic (As), cadmium (Cd), antimony (Sb), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn) were determined using inductively coupled plasma-optical emission spectrometry at the International Institute of Tropical Agriculture, Ibadan, Nigeria.

Results: The concentration of metals detected in water samples were higher than permissible limits at more than 50% of the sampling locations. In contrast, heavy metals in soil were within permissible limits. Most of the heavy metals except Pb were found to be present in the plant within permissible limits. Lead levels in water and plants from all locations exceeded the permissible limits. The contamination degree and pollution load index of water sources around the ULAB recycling center indicate a high degree of pollution of water sources with heavy metals, while soil samples were within the normal baseline levels. The transfer factor of Pb from soil to was 1.92. This has implications for human health as the plant is often harvested and for sale in local markets as a source of food and medicine.

Conclusions: The present study recommends improved technology for ULAB recycling and adequate treatment of effluent/runoff from recycling centers before discharge.

Competing Interests: The authors declare no competing financial interests.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5696/2156-9614-11.29.210304DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009648PMC
March 2021

Environmental Heavy Metal Contamination from Electronic Waste (E-Waste) Recycling Activities Worldwide: A Systematic Review from 2005 to 2017.

Int J Environ Res Public Health 2021 03 29;18(7). Epub 2021 Mar 29.

Department of Natural Resource Sciences, McGill University, Montreal, QC H9X 3V9, Canada.

The recycling of electronic waste (e-waste) contaminates ecosystems with metals, though a compilation of data from across sites worldwide is lacking, without which evidence-based comparisons and conclusions cannot be realized. As such, here, a systematic review of the literature was conducted to identify peer-reviewed studies concerning e-waste sites (published between 2005 and 2017) that reported on the concentration of heavy metals (Cd, Hg, As, Pb and Cr) in soil, water and sediment. From 3063 papers identified, 59 studies from 11 countries meeting predefined criteria were included. Reported metal concentrations were summarized, and a narrative synthesis was performed. This review summarized 8286 measurements of the aforementioned metals in soils (5836), water (1347) and sediment (1103). More than 70% of the studies were conducted in Asia. In nearly all cases, the average metal concentrations in a particular medium from a given site were above guideline values; suggesting soils, water and sediment at, or near, e-waste recycling sites are contaminated. Across all media, concentrations of Pb were generally highest, followed by Cr, As, Cd and Hg. The synthesized information demonstrates that e-waste sites worldwide are contaminated with metals, that geographic data gaps exist, that the quality of most studies can be improved and that action is needed to help reduce such levels to protect human health and the environment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph18073517DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8059143PMC
March 2021

Characterizing the effects of titanium dioxide and silver nanoparticles released from painted surfaces due to weathering on zebrafish ().

Nanotoxicology 2021 05 23;15(4):527-541. Epub 2021 Mar 23.

Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, Canada.

Silver (nAg) and titanium dioxide nanoparticles (nTiO) are common engineered nanoparticles (ENPs) added into paint for their antimicrobial and whitening properties, respectively. Weathering of outdoor painted surfaces can release such ENPs, though little is known about the potential effects of released ENPs on aquatic species. The objective of this study was to characterize the toxicity of nAg and nTiO released from painted panels using fish liver cells (CRL2643) and zebrafish embryos (OECD 236 embryotoxicity test). Cells and embryos were exposed to suspensions of pristine nAg or nTiO, panels (unpainted or painted with nAg or nTiO) or base paint, after sonication. Cell viability and gene expression were assessed using resazurin assay and qPCR, respectively, while embryo mortality and deformities were scored visually via microscopic examination. In the cell studies, both paint-released nanoparticles did not affect viability, but paint-released nAg resulted in differential expression of a few genes including and . In embryos, paint-released nAg increased mortality and incidence of deformities, whereas paint-released nTiO resulted in differential expression of several genes including , , , and but without major phenotypic abnormalities. Comparing the two types of exposures, paint-released exposures affected both molecular (gene expression) and apical (embryotoxicity) endpoints, while pristine exposures affected the expression of some genes but had no apical effects. The differing effects of paint-released and pristine nanoparticle exposures suggest that further research is needed to further understand how paint coatings (and the products of their weathering and aging) may influence nanoparticle toxicity to aquatic organisms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/17435390.2021.1897173DOI Listing
May 2021

Development of a Comprehensive Toxicity Pathway Model for 17α-Ethinylestradiol in Early Life Stage Fathead Minnows ().

Environ Sci Technol 2021 04 23;55(8):5024-5036. Epub 2021 Mar 23.

Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B3, Canada.

There is increasing pressure to develop alternative ecotoxicological risk assessment approaches that do not rely on expensive, time-consuming, and ethically questionable live animal testing. This study aimed to develop a comprehensive early life stage toxicity pathway model for the exposure of fish to estrogenic chemicals that is rooted in mechanistic toxicology. Embryo-larval fathead minnows (FHM; ) were exposed to graded concentrations of 17α-ethinylestradiol (water control, 0.01% DMSO, 4, 20, and 100 ng/L) for 32 days. Fish were assessed for transcriptomic and proteomic responses at 4 days post-hatch (dph), and for histological and apical end points at 28 dph. Molecular analyses revealed core responses that were indicative of observed apical outcomes, including biological processes resulting in overproduction of vitellogenin and impairment of visual development. Histological observations indicated accumulation of proteinaceous fluid in liver and kidney tissues, energy depletion, and delayed or suppressed gonad development. Additionally, fish in the 100 ng/L treatment group were smaller than controls. Integration of omics data improved the interpretation of perturbations in early life stage FHM, providing evidence of conservation of toxicity pathways across levels of biological organization. Overall, the mechanism-based embryo-larval FHM model showed promise as a replacement for standard adult live animal tests.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.est.0c05942DOI Listing
April 2021

Ultrafast functional profiling of RNA-seq data for nonmodel organisms.

Genome Res 2021 04 17;31(4):713-720. Epub 2021 Mar 17.

Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, Quebec H9X 3V9, Canada.

Computational time and cost remain a major bottleneck for RNA-seq data analysis of nonmodel organisms without reference genomes. To address this challenge, we have developed Seq2Fun, a novel, all-in-one, ultrafast tool to directly perform functional quantification of RNA-seq reads without transcriptome de novo assembly. The pipeline starts with raw read quality control: sequencing error correction, removing poly(A) tails, and joining overlapped paired-end reads. It then conducts a DNA-to-protein search by translating each read into all possible amino acid fragments and subsequently identifies possible homologous sequences in a well-curated protein database. Finally, the pipeline generates several informative outputs including gene abundance tables, pathway and species hit tables, an HTML report to visualize the results, and an output of clean reads annotated with mapped genes ready for downstream analysis. Seq2Fun does not have any intermediate steps of file writing and loading, making I/O very efficient. Seq2Fun is written in C++ and can run on a personal computer with a limited number of CPUs and memory. It can process >2,000,000 reads/min and is >120 times faster than conventional workflows based on de novo assembly, while maintaining high accuracy in our various test data sets.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1101/gr.269894.120DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8015844PMC
April 2021

Musculoskeletal Disorder Symptoms among Workers at an Informal Electronic-Waste Recycling Site in Agbogbloshie, Ghana.

Int J Environ Res Public Health 2021 02 19;18(4). Epub 2021 Feb 19.

Department of Biological Environmental and Occupational Health Sciences, School of Public Health, University of Ghana, Accra 00233, Ghana.

Informal recycling of electrical and electronic waste (e-waste) has myriad environmental and occupational health consequences, though information about the chronic musculoskeletal health effects on workers is limited. The aim of this study was to examine the prevalence and intensity of self-reported musculoskeletal disorder (MSD) symptoms among e-waste workers at Agbogbloshie in Ghana-the largest informal e-waste dumpsite in West Africa-relative to workers not engaged in e-waste recycling. A standardized musculoskeletal discomfort questionnaire was administered to 176 e-waste workers (73 collectors, 82 dismantlers, and 21 burners) and 41 workers in a reference group. The number of body parts with musculoskeletal discomfort were 1.62 and 1.39 times higher for collectors and dismantlers than burners, respectively. A 1-week discomfort prevalence was highest for collectors (91.8%) followed by dismantlers (89%), burners (81%), and the reference group (70.7%). The discomfort prevalence for e-waste workers was highest in the lower back (65.9%), shoulders (37.5%), and knees (37.5%). Whole-body pain scores (mean ± SE) were higher for collectors (83.7 ± 10.6) than dismantlers (45.5 ± 7.6), burners (34.0 ± 9.1), and the reference group (26.4 ± 5.9). Differences in prevalence, location, and intensity of MSD symptoms by the e-waste job category suggest specific work-related morbidity. Symptom prevalence and intensity call attention to the high risk for MSDs and work disability among informal e-waste workers, particularly collectors and dismantlers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph18042055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7923259PMC
February 2021

Micronutrient Status of Electronic Waste Recyclers at Agbogbloshie, Ghana.

Int J Environ Res Public Health 2020 12 21;17(24). Epub 2020 Dec 21.

Department of Biological, Environmental & Occupational Health Sciences, School of Public Health, University of Ghana, Accra +233, Ghana.

Growing evidence suggests that micronutrient status is adversely impacted by toxic metals (e.g., cadmium, lead, and arsenic) exposures; however, the micronutrient status of e-waste recyclers who are amongst the highest metal-exposed groups is not known. This study, therefore, assessed the micronutrient status of e-waste recyclers using dietary information (2-day 24-h recall survey) and biomarker data (whole blood and urine) among 151 participants (100 e-waste recyclers at Agbogbloshie and 51 controls at Madina Zongo from the Accra region, Ghana) in March 2017. Biomarker levels of iron (Fe), calcium (Ca), magnesium (Mg), selenium (Se), zinc (Zn) and copper (Cu) were analyzed by the ICP-MS. Linear regression models were used to assess associations ofwork-related factors and sociodemographic characteristics with micronutrient intake, blood, and urine micronutrient levels. The results showed that apart from Fe and Zn, e-waste recyclers at Agbogbloshie did not meet the day-to-day dietary requirements for Ca, Cu, Se, and Mg intake. Except for the low levels of Mg and Fe detected in blood of e-waste recyclers, all other micronutrients measured in both blood and urine of both groups fell within their reference range. Exposure to biomass burning was associated with lower blood levels of Fe, Mg, and Zn among the e-waste recyclers. Further, among e-waste recyclers, significant relationships were found between the number of years spent recycling e-waste and urinary Ca and Cu excretion. Given that, some dietary and blood levels of micronutrients were below their reference ranges, the implementation of evidence-based nutrition strategies remains necessary among e-waste recyclers to reduce their risk of becoming malnourished.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph17249575DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7767402PMC
December 2020

Dried blood spots to characterize mercury speciation and exposure in a Colombian artisanal and small-scale gold mining community.

Chemosphere 2021 Mar 19;266:129001. Epub 2020 Nov 19.

Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, H9X 3V9, Canada. Electronic address:

The artisanal and small-scale gold mining (ASGM) sector uses the most mercury (Hg) worldwide. Despite health concerns associated with high Hg exposures in these communities, ASGM sites are often situated in resource limited and remote regions which challenge traditional human biomonitoring approaches. To help overcome such challenges, here we report on the development of a high-quality method to characterize chemical speciation of Hg in dried blood spots (DBS), and then apply this method to assess Hg exposures in people sampled from an ASGM community (Pueblito Mejia) and a nearby town (Barranco de Loba) in Colombia. We collected DBS and urine samples from 35 individuals in 2018, and used these to assess occupational (DBS inorganic Hg (InHg) and urine total Hg (THg) measures) and environmental (DBS methylmercury (MeHg) measures) exposure of participants to different forms of Hg. The accuracy and precision of the DBS-based measures generally met assay performance guideline. In study participants, the mean concentrations of DBS MeHg, InHg, and THg, and urine THg were 1.9, 4.1, 6.0, and 3.1 μg/L, respectively. For 37% of the participants, DBS THg values exceeded the 5 μg/L 'alert level' proposed by the German HBM Commission. About 60% of the blood Hg was in the InHg form thus exemplifying a need to speciate Hg in blood sampled from ASGM sites to better understand the contributions of environmental and occupational exposure sources. This study demonstrates the feasibility of using DBS for Hg speciation exposure assessments in remote and resource-limited areas such as ASGM communities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2020.129001DOI Listing
March 2021

In utero and peripubertal metals exposure in relation to reproductive hormones and sexual maturation and progression among boys in Mexico City.

Environ Health 2020 11 25;19(1):124. Epub 2020 Nov 25.

Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI, 48109, USA.

Background: Endocrine disrupting chemicals (EDCs) such as metals have been reported to alter circulating reproductive hormone concentrations and pubertal development in animals. However, the relationship has rarely been investigated among humans, with the exception of heavy metals, such as Pb and Cd. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone concentrations and sexual maturation and progression among boys from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts.

Methods: Our analysis included 118 pregnant women and their male children from the ELEMENT study. Essential and non-essential metals were measured in urine collected from the mothers during the third trimester of pregnancy and their male children at 8-14 years. Reproductive hormone concentrations [serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG)] were measured in blood samples from the children at 8-14 years. We also assessed Tanner stages for sexual maturation (genital, pubic hair development, and testicular volume), at two time points (8-14, 10-18 years). We used linear regression to independently examine urinary metal concentrations in relation to each peripubertal reproductive hormones adjusting for child age and BMI. Generalized estimation equations (GEEs) were used to evaluate the association of in utero and peripubertal metal exposures with sexual maturation and progression during follow-up based on Tanner staging and testicular volume.

Results: In utero and prepubertal concentrations of some urinary metals were associated with increased concentrations of peripubertal reproductive hormones, especially non-essential metal(loid)s As and Cd (in utero), and Ba (peripubertal) as well as essential metal Mo (in utero) in association with testosterone. More advanced pubic hair developmental stage and higher testicular volume at the early teen visit was observed for boys with higher non-essential metal concentrations, including in utero Al and peripubertal Ba, and essential metal Zn concentration (peripubertal). These metals were also associated with slower pubertal progression between the two visits.

Conclusion: These findings suggest that male reproductive development may be associated with both essential and non-essential metal exposure during in utero and peripubertal windows.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12940-020-00672-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7688001PMC
November 2020

Lead (Pb) exposure assessment in dried blood spots using Total Reflection X-Ray Fluorescence (TXRF).

Environ Res 2021 07 10;198:110444. Epub 2020 Nov 10.

Faculty of Agricultural and Environmental Sciences, McGill University, Ste-Anne-de-Bellevue, Québec, Canada. Electronic address:

Lead (Pb) exposure is often determined through the analysis of whole blood though venipuncture poses ethical, economic, and logistical barriers. Dried Blood Spots (DBS) may help overcome such barriers though past studies measuring Pb in DBS have been challenged with quality control, small sample volumes, and other issues. Total Reflection X-Ray Fluorescence (TXRF) may help address some of these challenges but has yet to be used to measure Pb in DBS. As such, the aim of the current study was to develop, validate, and apply a method to analyze Pb in DBS samples using TXRF for use in human biomonitoring studies. First, we developed a novel method (tested a range of parameters), and then used blood reference materials to validate the method against performance criteria listed in ICH Q2A and Q2B and the European Bioanalysis Forum. Finally, we applied the method to two populations who exemplify divergent conditions (41 university members with relatively low Pb exposures sampled in a clinical environment; 40 electronic waste workers with relatively high Pb exposures sampled in a contaminated field setting). The limits of detection and quantification of the method were 0.28 and 0.69 μg/dL, respectively. The overall precision and accuracy of the method were 15% and 111%, respectively. The mean (±SD) DBS Pb levels by TXRF in the university members and e-waste workers were 0.78 (±0.46) and 3.78 (±3.01) μg/dL, respectively, and these were not different from Pb measures in venous whole blood using ICP-MS. Bland-Altman plot analyses indicated good agreement between DBS Pb measures by TXRF versus whole blood Pb measures by ICP-MS in both groups. By combining data from the two population groups, there was no significant constant bias (intercept of 0.02 μg/dL) or proportional bias (slope was -0.02) between the two measures, and the lower and upper LoA were -0.86 and 0.91 μg/dL, respectively, with a LoA range of 1.77 μg/dL. These results demonstrate that TXRF-based analysis of Pb content in DBS is a good alternative to the gold standard (i.e., ICP-MS analysis of whole blood), and helps overcome some of the challenges associated with current methods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2020.110444DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8107194PMC
July 2021

Effects on Apical Outcomes of Regulatory Relevance of Early-Life Stage Exposure of Double-Crested Cormorant Embryos to 4 Environmental Chemicals.

Environ Toxicol Chem 2021 02 18;40(2):390-401. Epub 2020 Dec 18.

Department of Natural Resource Sciences, McGill University, Montreal, Quebec, Canada.

Environmental risk assessment is often challenged by a lack of toxicity data for ecological species. The overall goal of the present study was to employ an avian early-life stage toxicity test to determine the effects of 4 chemicals (benzo[a]pyrene [BaP], chlorpyrifos, fluoxetine hydrochloride [FLX], and ethinyl estradiol [EE2]) on an ecologically relevant avian species, the double-crested cormorant (Phalacrocorax auritus), and to compare our results with those we previously reported for a laboratory model species, Japanese quail. Chemicals were dissolved in dimethyl sulfoxide and administered via air cell injection to fertilized, unincubated double-crested cormorant eggs at 3 nominal concentrations, the highest selected to approximate the 20% lethal dose. Of the 4 chemicals, only chlorpyrifos and FLX were detected in liver tissue of embryos at midincubation (day 14) and termination (day 26; 1-2 d prior to hatch); EE2 and BaP were not detectable, suggesting embryonic clearance/metabolism. No apical effects were observed in double-crested cormorant embryos up to the highest concentrations of chlorpyrifos (no-observed-effect level [NOEL] = 25 µg/g) or FLX (NOEL = 18 µg/g). Exposure to EE2 reduced embryonic viability and increased deformities at a concentration of 2.3 µg/g (NOEL = 0.18 µg/g), and BaP decreased embryonic viability (median lethal dose = 0.015 µg/g; NOEL = 0.0027 µg/g). Compared with Japanese quail, double-crested cormorant were more sensitive with regard to embryolethality and deformities for EE2 and embryolethality for BaP, whereas they were less sensitive to embryonic deformities associated with chlorpyrifos exposure. These data reinforce the idea that standardized toxicity tests using a laboratory model species may not always be protective of wild birds, and thus they stress the importance of developing such alternative testing strategies (e.g., the EcoToxChip Project) for ecologically relevant species to augment risk assessment efforts. Environ Toxicol Chem 2021;40:390-401. © 2020 SETAC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.4922DOI Listing
February 2021

Drivers of and Obstacles to the Adoption of Toxicogenomics for Chemical Risk Assessment: Insights from Social Science Perspectives.

Environ Health Perspect 2020 10 28;128(10):105002. Epub 2020 Oct 28.

University of Sydney Business School and University of Sydney Nano Institute, Sydney, New South Wales, Australia; Department of Chemistry, Faculty of Science, McGill University, Montreal, Quebec, Canada.

Background: Some 20 y ago, scientific and regulatory communities identified the potential of omics sciences (genomics, transcriptomics, proteomics, metabolomics) to improve chemical risk assessment through development of toxicogenomics. Recognizing that regulators adopt new scientific methods cautiously given accountability to diverse stakeholders, the scope and pace of adoption of toxicogenomics tools and data have nonetheless not met the ambitious, early expectations of omics proponents.

Objective: Our objective was, therefore, to inventory, investigate, and derive insights into drivers of and obstacles to adoption of toxicogenomics in chemical risk assessment. By invoking established social science frameworks conceptualizing innovation adoption, we also aimed to develop recommendations for proponents of toxicogenomics and other new approach methodologies (NAMs).

Methods: We report findings from an analysis of 56 scientific and regulatory publications from 1998 through 2017 that address the adoption of toxicogenomics for chemical risk assessment. From this purposeful sample of toxicogenomics discourse, we identified major categories of drivers of and obstacles to adoption of toxicogenomics tools and data sets. We then mapped these categories onto social science frameworks for conceptualizing innovation adoption to generate actionable insights for proponents of toxicogenomics.

Discussion: We identify the most salient drivers and obstacles. From 1998 through 2017, adoption of toxicogenomics was understood to be helped by drivers such as those we labeled , , and but hindered by obstacles such as those we labeled , , and . Leveraging social science frameworks, we find that arguments for adoption that draw on the most salient drivers, which emphasize superior and novel functionality of omics as rationales, overlook potential adopters' key concerns: simplicity of use and compatibility with existing practices. We also identify two perspectives-innovation-centric and adopter-centric-on omics adoption and explain how overreliance on the former may be undermining efforts to promote toxicogenomics. https://doi.org/10.1289/EHP6500.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1289/EHP6500DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7592882PMC
October 2020

Mercury exposure in relation to sleep duration, timing, and fragmentation among adolescents in Mexico City.

Environ Res 2020 12 18;191:110216. Epub 2020 Sep 18.

Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA.

Introduction: Mercury intoxication is known to be associated with adverse symptoms of fatigue and sleep disturbances, but whether low-level mercury exposure could affect sleep remains unclear. In particular, children may be especially vulnerable to both mercury exposures and to poor sleep. We sought to examine associations between mercury levels and sleep disturbances in Mexican youth.

Methods: The study sample comprised 372 youth from the Early Life Exposures to Environmental Toxicants (ELEMENT) cohort, a birth cohort from Mexico City. Sleep (via 7-day actigraphy) and concurrent urine mercury were assessed during a 2015 follow-up visit. Mercury was also assessed in mid-childhood hair, blood, and urine during an earlier study visit, and was considered a secondary analysis. We used linear regression and varying coefficient models to examine non-linear associations between Hg exposure biomarkers and sleep duration, timing, and fragmentation. Unstratified and sex-stratified analyses were adjusted for age and maternal education.

Results: During the 2015 visit, participants were 13.3 ± 1.9 years, and 48% were male. There was not a cross-sectional association between urine Hg and sleep characteristics. In secondary analysis using earlier biomarkers of Hg, lower and higher blood Hg exposure was associated with longer sleep duration among girls only. In both boys and girls, Hg biomarker levels in 2008 were associated with later adolescent sleep midpoint (for Hg urine in girls, and for blood Hg in boys). For girls, each unit log Hg was associated with 0.2 h later midpoint (95% CI 0 to 0.4), and for boys each unit log Hg was associated with a 0.4 h later sleep midpoint (95% CI 0.1 to 0.8).

Conclusions: There were mostly null associations between Hg exposure and sleep characteristics among Mexican children. Yet, in both boys and girls, higher Hg exposure in mid-childhood (measured in urine and blood, respectively) was related to later sleep timing in adolescence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envres.2020.110216DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7750915PMC
December 2020

FastBMD: an online tool for rapid benchmark dose-response analysis of transcriptomics data.

Bioinformatics 2021 05;37(7):1035-1036

Department of Natural Resource Sciences, McGill University, Montreal, QC H9X 3V9, Canada.

Motivation: Transcriptomics dose-response analysis is a promising new approach method for toxicity testing. While international regulatory agencies have spent substantial effort establishing a standardized statistical approach, existing software that follows this approach is computationally inefficient and must be locally installed.

Results: FastBMD is a web-based tool that implements standardized methods for transcriptomics benchmark dose-response analysis in R. It is >60 times faster than the current leading software, supports transcriptomics data from 13 species, and offers a comprehensive analytical pipeline that goes from processing and normalization of raw gene expression values to interactive exploration of pathway-level benchmark dose results.

Availability And Implementation: FastBMD is freely available at www.fastbmd.ca.

Supplementary Information: Supplementary data are available at Bioinformatics online.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/bioinformatics/btaa700DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8128449PMC
May 2021
-->