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Patel A.B.,National Institute of Occupational Health NIOH | Dewan A.,National Institute of Occupational Health NIOH | Kaji B.C.,Meghaninagar Civil Hospital
Arhiv za Higijenu Rada i Toksikologiju | Year: 2012

Several episodes of mass poisoning by organophosphates (OPs) have been reported from the developing countries. The diagnosis of OP-poisoning is mainly based on the characteristic clinical features and history of exposure to a known OP compound. Estimation of serum and red blood cell (RBC) cholinesterase activities are helpful in confirming the diagnosis. However, there is controversy regarding a definite relationship between serum cholinesterase activity and the severity of clinical manifestations and prognosis. This report describes an episode of mass monocrotophos poisoning that occurred due to accidental ingestion of monocrotophos-contaminated millet (so called bavta) flour involving eight severely poisoned persons. Clinical presentation included severe abdominal pain, diarrhoea, vomiting, pupil narrowing, and difficulty breathing. On hospital admission, plasma cholinesterase (PChE) and especially RBC acetylcholinesterase (AChE) activities correlated well with clinical symptoms presented by the patients. This case study highlights the need for clinicians to be aware of OP-pesticide poisoning from food sources and the need to look for depressed PChE and AChE activities that may point to OP exposure, so that OP-poisoning can be identified immediately and patients can receive specific treatment, rather than general treatment for food poisoning.


Yah C.S.,National Institute of Occupational Health NIOH | Iyuke S.E.,University of Witwatersrand | Simate G.S.,University of Witwatersrand | Unuabonah E.I.,Redeemer's University | And 3 more authors.
Journal of Materials Research | Year: 2011

This work reports the continuous and large-scale production of multiwalled carbon nanotubes (MWCNTs) from xylene/ferrocene in a swirled floating catalyst chemical vapor deposition reactor using argon as the carrier gas. The concentration of ferrocene used was 0.01 g/mL of xylene. In every run, 50-mL xylene gas was used together with xylene/ferrocene mixture injected into the reactor by means of a burette. The MWCNTs produced were characterized using the transmission electron microscopy (TEM) and Raman spectra. TEM analysis showed a poor production rate at 850 °C and a good production in the range of 900-1000 °C with optimal production rate at 950 °C. Furthermore, xylene/ferrocene mixture produced more MWCNTs at 950 °C with H:Ar (1:7) as the carrier gas. The diameters of the MWCNTs in the temperatures studied ranged from 15 to 95 nm with wall thicknesses between 0.5 and 0.8 nm. © 2011 Materials Research Society.


Hansen S.,University of Tromsø | Nieboer E.,University of Tromsø | Nieboer E.,McMaster University | Sandanger T.M.,University of Tromsø | And 5 more authors.
Journal of Environmental Monitoring | Year: 2011

The objective of this study was to investigate changes in the levels of toxic and essential elements in maternal blood during pregnancy and subsequently. A subset of 211 pregnant women from the North Norwegian Mother-and-Child Study was included. Blood samples were collected during the 2 nd trimester (P1) and postpartum (day 3, P2; and 6 weeks, P3) in different regions of northern Norway, and were analyzed for a suite of 10 selected elements. The latter feature three general but distinct concentration patterns across the three collection periods, namely: progressive increase [Group 1: As, Cd (non-smokers only), Mn, Pb and Zn]; V-shaped, with a minimum at P2 [Group 2: Cd (smokers), Hg, Mo and Se]; and downward V, with a maximum at P2 [Group 3: Co and Cu]. These trends are interpreted in the context of underlying metabolic, hematological and physiological changes that occur in mothers, as well the biochemistry and accumulation preferences of these elements within the whole blood compartment and breast milk. Implications for biomonitoring strategies are discussed. In a multivariable analysis of the P1 data, fish consumption was a robust positive predictor for Hg (p < 0.02), As (p < 0.01) and Se (p ≤ 0.001) blood concentrations, multivitamin intake for Se (p < 0.001), and parity for Co (p < 0.002); age reached significance only for Hg (p < 0.001). An inverse association was observed between parity and Hg (p < 0.05). For the other elements, predictor patterns were not evident. © 2011 The Royal Society of Chemistry.


Shah A.J.,Gujarat University | Lakkad B.C.,National Institute of Occupational Health NIOH | Rao M.V.,Gujarat University
Indian Journal of Experimental Biology | Year: 2016

Lead (Pb) which plays a significant role in modern industry is related to a broad range of physiological, biochemical, behavioural and genetical dysfunctions. Its exposure leads to an increased frequency of genetic aberrations in humans. Hence, this study was designed to assess the genotoxic effect of lead acetate at three dosage levels (10, 25 and 50 μg/mL) by employing: the Cytokinesis Block Micronucleus (CBMN) assay and the Comet assay in Peripheral Blood Lymphocyte Cultures. The results of this study revealed an increased level of DNA damage among treated groups. A significant increase in the tail length of comets and other indices was observed at 25 and 50 μg/mL concentrations comparatively. Thus, lead acetate induced single-strand breaks (SSB) and double strand breaks (DSB) in DNA, alkali-labile sites (ALS), oxidative DNA damage as well as DNA-DNA/DNA-protein/DNA-metal cross linking as evidenced by the Comet assay. The chromosome breakage, DNA misrepair, chromosome loss and telomere end fusion were determined by the Micronucleus assay. Micronucleus frequency in treated lymphocytes was significantly higher as compared to controls. Nucleoplasmic bridges increased significantly and Nuclear buds increased at higher two doses only in exposed cultures. Thus, these assays are better indices for lead induced genotoxicity and metal-nucleus interactions. © 2016, National Institute of Science Communication. All rights reserved.


Veyhe A.S.,Anna University | Hofoss D.,Health Science University | Hansen S.,Health Science University | Thomassen Y.,National Institute of Occupational Health NIOH | And 3 more authors.
International journal of hygiene and environmental health | Year: 2015

BACKGROUND: Although predictors of contaminants in serum or whole blood are usually examined by chemical groups (e.g., POPs, toxic and/or essential elements; dietary sources), principal component analysis (PCA) permits consideration of both individual substances and combined variables.OBJECTIVES: Our study had two primary objectives: (i) Characterize the sources and predictors of a suite of eight PCBs, four organochlorine (OC) pesticides, five essential and five toxic elements in serum and/or whole blood of pregnant women recruited as part of the Mother-and-Child Contaminant Cohort Study conducted in Northern Norway (The MISA study); and (ii) determine the influence of personal and social characteristics on both dietary and contaminant factors.METHODS: Recruitment and sampling started in May 2007 and continued for the next 31 months until December 2009. Blood/serum samples were collected during the 2nd trimester (mean: 18.2 weeks, range 9.0-36.0). A validated questionnaire was administered to obtain personal information. The samples were analysed by established laboratories employing verified methods and reference standards. PCA involved Varimax rotation, and significant predictors (p≤0.05) in linear regression models were included in the multivariable linear regression analysis.RESULTS: When considering all the contaminants, three prominent PCA axes stood out with prominent loadings of: all POPs; arsenic, selenium and mercury; and cadmium and lead. Respectively, in the multivariate models the following were predictors: maternal age, parity and consumption of freshwater fish and land-based wild animals; marine fish; cigarette smoking, dietary PCA axes reflecting consumption of grains and cereals, and food items involving hunting. PCA of only the POPs separated them into two axes that, in terms of recently published findings, could be understood to reflect longitudinal trends and their relative contributions to summed POPs.CONCLUSIONS: The linear combinations of variables generated by PCA identified prominent dietary sources of OC groups and of prominent toxic elements and highlighted the importance of maternal characteristics. Copyright © 2014 Elsevier GmbH. All rights reserved.


Nigam S.K.,National Institute of Occupational Health NIOH | Venkatakrishna-Bhatt H.,NIOH
Eurasian Journal of Medicine | Year: 2013

Objective: Betel leaf combined with areca nut is known as betel quid pan masala (PM), and tobacco with areca nut, catechu and lime is pan masala (PMT) blended with gulkhand. These narcotics are popular among young and old individuals. A prima facia chemical analysis and a toxicity assessment of PM in mice were conducted to study the relationship between longtime consumption of PM and health hazards. Materials and Methods: Chemical analysis of different types of PM was done employing HPLC, GLC, AAS, ES, TLC, GCMS and sequential extraction for PAH, pesticides, metals and minerals, electrolytes, drugs and xenobiotics. Ethanolic PM extracts were tested by IP and PO routes in inbred Swiss mice. Results: PAH, which are known xenobiotics for pre-cancerous lesions, were significantly high (p<0.01) in Rajaniganda and Pan Parag Zarda. Isomers of DDT and BHC, which principally act on nerves and muscles, were also high (p<0.01) in PM. The enhanced metal and mineral content of PM results in massive oral fibrosis. There is a high level of narcotics in PM, especially nicotine, a potentially cancerous agent in the gastrointestinal tract. Conclusion: Experimental studies with different extracts of plain and blended PM in mice fed for 16 and 90 days revealed no effect on blood and organ weights (kidney, heart, spleen and liver), but we did observe attenuated testis. However, in the bone marrow of the mice, chromosomes were most affected in the mice fed PM-Zarda blend for 3 months. The chromosomal abnormalities included ploidy, loss, breaks, gaps, deletions and exchanges in ring chromosomes. The PM caused sperm head anomalies (narrow, blunt, triangular and banana shapes), and the sperm were irregular, amorphous, tailless and rudimentary, with the maximum effect among the groups fed PM for 3 months. Significantly higher levels (p<0.01) of testis glycogen, cholesterol and protein were found. The group fed for 16 days showed no change in red blood corpuscles (RBC), white blood corpuscles (WBC), hemoglobin and erythrocyte sedimentation counts.


Bhagia L.J.,National Institute of Occupational Health NIOH | Vyas J.B.,National Institute of Occupational Health NIOH | Shaikh M.I.,National Institute of Occupational Health NIOH | Dodia S.L.,National Institute of Occupational Health NIOH
Environmental Monitoring and Assessment | Year: 2010

Exposure to asbestos fibers has been extensively studied in milling, mining of asbestos fibers, and in industries manufacturing asbestos- cement sheets, pipes, etc. However, very few studies have been reported in asbestos textiles, brake lining workers, and insulation products. In the present investigation, chrysotile exposure monitoring was carried out in a small thermal insulating boards manufacturing facility. Twenty-eight samples were analyzed from various locations like feeding of raw materials, weighing, pressing, machine grinding, and hand finishing of final products. Twenty-five percent of the samples were found to be above ACGIH TLV of 0.1 fibers per milliliter. However, mean fiber concentrations were found to be lower than 0.1 fibers per milliliter, except for the process of feeding of raw materials where the mean fiber concentration was 0.1087 ± 0.0631 fibers per milliliter. © Springer Science + Business Media B.V. 2009.


PubMed | National Institute of Occupational Health NIOH
Type: Journal Article | Journal: Indian journal of occupational and environmental medicine | Year: 2010

Manmade nanoparticles range from the well-established multi-ton production of carbon black and fumed silica for applications in plastic fillers and car tyres to microgram quantities of fluorescent quantum dots used as markers in biological imaging. While benefits of nanotechnology are widely publicized, the discussion of the potential effects of their widespread use in the consumer and industrial products are just beginning to emerge. Acceptance of nanoparticle toxicity led to wide acceptance of the fact that nanotoxicology, as a scientific discipline shall be quite different from occupational hygiene in approach and context. Understanding the toxicity of nanomaterials and nano-enabled products is important for human and environmental health and safety as well as public acceptance. Assessing the state of knowledge about nanotoxicology is an important step in promoting comprehensive understanding of the health and environmental implications of these new materials. Very limited data exist for health effects secondary to inhalation of very fine respirable particles in the occupational environment. Nanomaterials may have effects on health due to their size, surface, shape, charge, or other factors, which are not directly predictable from mass concentration measurements. Numerous epidemiological studies have associated exposure to small particles such as combustion-generated fine particles with lung cancer, heart disease, asthma and/or increased mortality. The omnipresence of nanoparticles shifts focus of research toward efforts to mitigate the health effects of nanoparticles. Newer health assessment methods and newer techniques need to be developed for diagnosing sub-optimal health in populations exposed to carbon nanoparticles.


PubMed | National Institute of Occupational Health NIOH
Type: Journal Article | Journal: Indian journal of human genetics | Year: 2011

Paraoxonase (PON1) can hydrolyze organophosphate pesticides (OP) and has a key role in the susceptibility of human in OP toxicity. The human-enzyme shows polymorphism and variations in the distribution profile of its phenotypes among different ethnic groups have been observed.To see the distribution pattern of total PON1 activity in 45 healthy attendants of poisoning cases; 121 healthy unrelated farm-labours and 59 normal subjects of trauma.The PON1 activities from serum/plasma samples of these healthy normal individuals were estimated with/without addition of 1M NaCl in order to determine salt-stimulated and basal activity. The PON 1 phenotypes were determined on the basis of percent activation of enzyme activity.Tri-modal distribution of basal PON1 activity was observed among all these individuals. 52.0% of the individuals belonged to Phenotype A, 46.6% to phenotype AB while 1.4% to Phenotype B with gene frequency of allele-A and allele-B being 0.753 and 0.247 respectively in excellent agreement with Hardy-Weinberg equilibrium.Maximum number of individuals belonged to phenotype-A (low PON1 activity) showing potential vulnerability towards Op-poisoning.


PubMed | National Institute of Occupational Health NIOH
Type: Journal Article | Journal: Environmental monitoring and assessment | Year: 2010

Exposure to asbestos fibers has been extensively studied in milling, mining of asbestos fibers, and in industries manufacturing asbestos-cement sheets, pipes, etc. However, very few studies have been reported in asbestos textiles, brake lining workers, and insulation products. In the present investigation, chrysotile exposure monitoring was carried out in a small thermal insulating boards manufacturing facility. Twenty-eight samples were analyzed from various locations like feeding of raw materials, weighing, pressing, machine grinding, and hand finishing of final products. Twenty-five percent of the samples were found to be above ACGIH TLV of 0.1 fibers per milliliter. However, mean fiber concentrations were found to be lower than 0.1 fibers per milliliter, except for the process of feeding of raw materials where the mean fiber concentration was 0.1087+/-0.0631 fibers per milliliter.

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