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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

The effects of selected pesticides on microorganisms in terrestrial and aquatic environments.

Charles, Norris C. January 1972 (has links)
No description available.
142

A cytogenetic study of the effects of pesticides.

Wuu, Kuang-Dong January 1966 (has links)
A cytogenetic study of the effects of 15 pesticides (herbicides: Alanap-3, Atrazine, Banvel D, Cytrol, Embutox E, Hyvar X, Lorox, Monuron, Simazine; insecticides: Endrin, Phosphamidon, Sevin; insect chemosterilants: ENT-50612, Metepa; fungicide: Botran) has been carried out with Hordeum vulgare and Vicia faba. [...]
143

Assessment of chemical exposure and self-reported health among tree planters in British Columbia

Gorman, Melanie Johanna 11 1900 (has links)
In British Columbia harvested forests are manually replanted by seasonal workers. Fertilizers contained in perforated paper sachets are often planted with seedlings. There have been anecdotal reports of skin and respiratory illness associated with fertilizer exposure and due to potential metal content in fertilizer source material they may contain metals as contaminants. Workers may also be exposed to pesticide residues on seedlings. This study aimed to characterize fertilizer, metal and pesticide exposure among a sample of B.C. tree planters, and to examine worker respiratory and dermal health. Between May 2006 and April 2007 223 tree planters were interviewed about their respiratory and dermal health, and the exposures of 54 tree planters at five geographically-disperse worksites were monitored. Four worksites were using fertilizer and one was not. The health questionnaire was a modification of the American Thoracic Society standardized questionnaire with questions on dermal health taken from a previous UBC study. Workers were grouped in exposure categories and symptoms analysed using logistic regression. Metals were measured by ICP/MS on post shift hand wipes, full shift air sample filters, in whole blood, bulk soil, seedling root balls, and fertilizer samples. Pesticides were measured on post shift hand wipes and on bulk seedling samples. Using nursery pesticide application records, analyses focused on known pesticides applied to the seedlings at the study sites. Carbamate pesticides were analyzed by HPLC/MS and other pesticides by GC/MS. No evidence was found that tree planters who work with fertilizer are at an elevated risk of exposure to arsenic, lead, cadmium, chromium and nickel relative to other tree planters. Pesticide residues were found on seedlings taken from coastal work sites in April 2007. At coastal worksites the fungicides chlorothalonil and iprodione were found on the skin of workers at low levels (range 0.37 – 106.3 ng.cm² and 0.48 – 15.9 ng/cm² respectively). Work with fertilizer was linked with an increased risk of cough, phlegm, nasal symptoms, nose bleed, and skin irritation. Hygiene conditions at tree planting work sites are very poor. Although measured exposures were low, hygiene conditions should improve to reduce the risk of health symptoms among tree planters.
144

Sublethal effects of pesticides in pipostrelle bats (Pipistrellus pipistrellus)

Swanepoel, Robert Eric January 1995 (has links)
No description available.
145

Sample preparation in environmental organic analysis

Barnabas, Ian Joseph January 1996 (has links)
No description available.
146

Kämpa eller bekämpa : En studie av trädgårdsägares tankar om ogräs, ohyra och bekämpningsmedel

Dahlbäck, Anna January 2014 (has links)
Statistics show that the sales of pesticides in Sweden are increasing. This study examines why this increase occurs, and who is buying the pesticides. The study has two aims: the first is to investigate the availability of pesticides for household use, and the second is to identify the problems garden owners are experiencing in the garden and the strategies they use to solve them. As a background to my work, some of the most debated pesticides and industrial chemicals with an impact on gardening during the 20th century are briefly summarized. The background section also includes a brief account of gardening in Sweden today. In my study, five garden stores were inventoried and staff were interviewed, garden owners were interviewed at allotment compounds and in home gardens, and an online survey was posted on a garden forum. The results indicate a wide variation in the range of pesticides in garden stores. The bigger stores have more varieties while the smaller stores have chosen to reduce the supply of pesticides. Interviews with the staff indicate that customers have little knowledge of pesticides and gardening in general. Many customers are looking for quick and easy solutions to their problems, the lawn being a big concern for many. Allotment owners use very little pesticides, while home gardeners and the respondents of the online survey use pesticides to a greater extent, but home gardeners often consider pesticides dangerous and want to decrease their use.
147

Bioremediation of the pesticides dieldrin, simazine, trifluralin using tropical and temperate white-rot fungi

Elyassi, Ali January 1997 (has links)
The natural breakdown of three pesticides on the UK Red List (dieldrin, simazine and trifluralin) in water and soil varied with environmental conditions. In both sterile and unsterile water, trifluralin was degraded to some extent at 20 and 30°C. In contrast, dieldrin and simazine were stable over the 42 days incubation period. A gradient HPLC method was developed for the simultaneous quantification of the three pesticides in soil. In field capacity soil mixtures of the three pesticides (5 and 10 ppm) showed a similar stability with limited degradation at 20°C but increased rates of degradation at 30°C. At the higher concentration the pesticides naturally degraded at a slower rate. Simazine and trifluralin degradation was significantly enhanced with increasing temperature from 20 to 30°C. Water potential (field capacity~ -0.065 MPa~ and - 0.28 MPa) had little effect on the natural breakdown rate of dieldrin. Simazine showed a greater breakdown in the mid-wetness soil~ while trifluralin was degraded rapidly in the field capacity soil, but not at all in the driest treatment over the 70 day experimental period. In vitro studies on solid agar media overlayed with cellophane showed that of four fungi examined~ Trametes cingulata, Trametes socotrana (tropical species) and Phanerochaete chrysosporium and Polystictus versicolor (temperate species) all except P.chrysosporium were able to grow in the presence of 5 ppm of any of the three pesticides at 20 and 30°C, with the latter only growing at 30°C. At 10 ppm concentration P. chrysosporium did not grow, regardless of temperature or time of incubation (up to 56 days). HPLC was used to quantify the temporal rates of degradation in the solid agar media and this showed that P. versicolor and T. socotrana were very effective at breaking down the three pesticides, at 20 and 30°C. The chosen fungi were grown on chopped straw as a carrier and incorporated into soil microcosms in the ratio of 1:10 containing mixtures of the three pesticides (5, 10 ppm) at 20 and 30°C, and subsequently under different water potential regimes at 20°C only, over periods of 70 days. P. versicolor alone significantly increased breakdown of 5 ppm dieldrin by 26% over untreated controls, while simazine breakdown was increased by 16%. However, for simazine at 30°C there was no difference between temporal rates of natural breakdown and those containing fungal inocula, regardless of concentration. With 5 ppm trifluralin, a maximum breakdown in untreated soil was 67% after 70 days. By contras~ this pesticide was undetectable after 28 days in the presence of the inoculant P . versicolor. This increased to 42 days where a mixture of the two fungi were used. Generally the mixture of fungi used in this study were not as effective in bioremediation of these pesticides as a single species. Field capacity soil appeared to be the best condition for P. versicolor to degrade dieldrin and trifluralin added at 10 ppm. However, for simazine this occurred in the driest water potential (-0.28 MPa) used.
148

Assessment of chemical exposure and self-reported health among tree planters in British Columbia

Gorman, Melanie Johanna 11 1900 (has links)
In British Columbia harvested forests are manually replanted by seasonal workers. Fertilizers contained in perforated paper sachets are often planted with seedlings. There have been anecdotal reports of skin and respiratory illness associated with fertilizer exposure and due to potential metal content in fertilizer source material they may contain metals as contaminants. Workers may also be exposed to pesticide residues on seedlings. This study aimed to characterize fertilizer, metal and pesticide exposure among a sample of B.C. tree planters, and to examine worker respiratory and dermal health. Between May 2006 and April 2007 223 tree planters were interviewed about their respiratory and dermal health, and the exposures of 54 tree planters at five geographically-disperse worksites were monitored. Four worksites were using fertilizer and one was not. The health questionnaire was a modification of the American Thoracic Society standardized questionnaire with questions on dermal health taken from a previous UBC study. Workers were grouped in exposure categories and symptoms analysed using logistic regression. Metals were measured by ICP/MS on post shift hand wipes, full shift air sample filters, in whole blood, bulk soil, seedling root balls, and fertilizer samples. Pesticides were measured on post shift hand wipes and on bulk seedling samples. Using nursery pesticide application records, analyses focused on known pesticides applied to the seedlings at the study sites. Carbamate pesticides were analyzed by HPLC/MS and other pesticides by GC/MS. No evidence was found that tree planters who work with fertilizer are at an elevated risk of exposure to arsenic, lead, cadmium, chromium and nickel relative to other tree planters. Pesticide residues were found on seedlings taken from coastal work sites in April 2007. At coastal worksites the fungicides chlorothalonil and iprodione were found on the skin of workers at low levels (range 0.37 – 106.3 ng.cm² and 0.48 – 15.9 ng/cm² respectively). Work with fertilizer was linked with an increased risk of cough, phlegm, nasal symptoms, nose bleed, and skin irritation. Hygiene conditions at tree planting work sites are very poor. Although measured exposures were low, hygiene conditions should improve to reduce the risk of health symptoms among tree planters.
149

Immunotoxic effects of aldicarb /

The Dean, Timothy Neal, January 1990 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 78-85). Also available via the Internet.
150

Participatory action research and testing the effectiveness of stinging nettle as a biopesticide in Kenya /

Kaberia, Doris K. January 2007 (has links) (PDF)
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2007. / Includes bibliographical references (leaves 74-79).

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